U.S. patent application number 13/221817 was filed with the patent office on 2011-12-29 for organic phase change carriers containing nanoparticles, phase change inks including same and methods for making same.
This patent application is currently assigned to XEROX CORPORATION. Invention is credited to Jennifer L. Belelie, Marcel P. Breton, Rina Carlini, H. Bruce Goodbrand, Adela Goredema, Nan-Xing Hu, Peter G. Odell.
Application Number | 20110316926 13/221817 |
Document ID | / |
Family ID | 38820567 |
Filed Date | 2011-12-29 |
United States Patent
Application |
20110316926 |
Kind Code |
A1 |
Breton; Marcel P. ; et
al. |
December 29, 2011 |
Organic Phase Change Carriers Containing Nanoparticles, Phase
Change Inks Including Same and Methods for Making Same
Abstract
Disclosed is an organic phase change carrier and a method for
forming same, and a phase change ink including same. The organic
phase change carrier comprises a colloidal dispersion of
nanoparticles exhibiting a substantially uniform distribution of
said nanoparticles discretely distributed therewithin, at least one
curable monomer; a phase change inducing component, and an
initiator. The organic phase change carrier exhibits a
substantially uniform distribution of the nanoparticles so that
they are discretely distributed therewithin, and are substantially
resistant to the aggregation of the nanoparticles distributed
therewithin.
Inventors: |
Breton; Marcel P.;
(Mississauga, CA) ; Belelie; Jennifer L.;
(Oakville, CA) ; Odell; Peter G.; (Mississauga,
CA) ; Carlini; Rina; (Mississauga, CA) ;
Goredema; Adela; (Mississauga, CA) ; Goodbrand; H.
Bruce; (Hamilton, CA) ; Hu; Nan-Xing;
(Oakville, CA) |
Assignee: |
XEROX CORPORATION
Norwalk
CT
|
Family ID: |
38820567 |
Appl. No.: |
13/221817 |
Filed: |
August 30, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12553057 |
Sep 2, 2009 |
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13221817 |
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11423777 |
Jun 13, 2006 |
7699922 |
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12553057 |
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Current U.S.
Class: |
347/20 ; 522/75;
977/773 |
Current CPC
Class: |
C09D 11/34 20130101 |
Class at
Publication: |
347/20 ; 522/75;
977/773 |
International
Class: |
B41J 2/015 20060101
B41J002/015; C09D 11/10 20060101 C09D011/10 |
Claims
1. An organic phase change carrier comprising (A) a colloidal
dispersion of nanoparticles exhibiting a substantially uniform
distribution of said nanoparticles discretely distributed
therewithin so that it is capable of controlling the transfuse
properties of the ink; (B) at least one curable monomer; (C) a
phase change inducing component comprising at least one of a
gellant and a solid alcohol compound; and (D) an initiator, said
organic phase change carrier being resistant to substantial
aggregation of said nanoparticles distributed therewithin, wherein
said organic phase change carrier is combinable with a colorant to
produce a phase change ink which can be formed into liquid droplets
and ejected from a phase change ink printing apparatus in an
imagewise pattern onto a substrate to form a predetermined pattern
of ink drops, wherein said liquid droplets can comprise gelled ink
droplets which can be transferred from an intermediate transfer
surface to an image receiving surface for transfuse printing, said
phase change inks being capable of generating prints with good
performance in automatic document feeders.
2. A phase change ink comprising a colorant and the organic phase
change carrier according to claim 1.
3. An organic phase change carrier according to claim 1, wherein
said nanoparticles comprise at least one of silica particles and
metal oxide particles.
4. An organic phase change carrier according to claim 1, wherein
said metal oxide nanoparticles comprise aluminium oxide, antimony
tin oxide, antimonyl pentoxide, and zinc oxide.
5. An organic phase change carrier according to claim 1, wherein
said nanoparticles comprise tecton-modified silica
nanoparticles.
6. An organic phase change carrier according to claim 1, wherein
the gellant is a compound represented by the formula ##STR00059##
wherein R1 is (i) an alkylene group, including linear and branched,
saturated and unsaturated, cyclic and acyclic, and substituted and
unsubstituted alkylene groups, and wherein heteroatoms either may
or may not be present in the alkylene group, (ii) an arylene group,
including substituted and unsubstituted arylene groups, and wherein
heteroatoms either may or may not be present in the arylene group,
(iii) an arylalkylene group, including substituted and
unsubstituted arylalkylene groups, wherein the alkyl portion of the
arylalkylene group can be linear or branched, saturated or
unsaturated, and cyclic or acyclic, and wherein heteroatoms either
may or may not be present in either the aryl or the alkyl portion
of the arylalkylene group, or (iv) an alkylarylene group, including
substituted and unsubstituted alkylarylene groups, wherein the
alkyl portion of the alkylarylene group can be linear or branched,
saturated or unsaturated, and cyclic or acyclic, and wherein
heteroatoms either may or may not be present in either the aryl or
the alkyl portion of the alkylarylene group, R2 and R2' each,
independently of the other, are (i) alkylene groups, including
linear and branched, saturated and unsaturated, cyclic and acyclic,
and substituted and unsubstituted alkylene groups, and wherein
heteroatoms either may or may not be present in the alkylene group,
(ii) arylene groups, including substituted and unsubstituted
arylene groups, and wherein heteroatoms either may or may not be
present in the arylene group, (iii) arylalkylene groups, including
substituted and unsubstituted arylalkylene groups, wherein the
alkyl portion of the arylalkylene group can be linear or branched,
saturated or unsaturated, and cyclic or acyclic, and wherein
heteroatoms either may or may not be present in either the aryl or
the alkyl portion of the arylalkylene group, or (iv) alkylarylene
groups, including substituted and unsubstituted alkylarylene
groups, wherein the alkyl portion of the alkylarylene group can be
linear or branched, saturated or unsaturated, and cyclic or
acyclic, and wherein heteroatoms either may or may not be present
in either the aryl or the alkyl portion of the alkylarylene group,
R3 and R3' each, independently of the other, are either (a)
photoinitiating groups, or (b) groups which are (i) alkyl groups,
including linear and branched, saturated and unsaturated, cyclic
and acyclic, and substituted and unsubstituted alkyl groups, and
wherein heteroatoms either may or may not be present in the alkyl
group, (ii) aryl groups, including substituted and unsubstituted
aryl groups, wherein heteroatoms either may or may not be present
in the aryl group, (iii) arylalkyl groups, including substituted
and unsubstituted arylalkyl groups, wherein the alkyl portion of
the arylalkyl group can be linear or branched, saturated or
unsaturated, and cyclic or acyclic, and wherein heteroatoms either
may or may not be present in either the aryl or the alkyl portion
of the arylalkyl group, or (iv) alkylaryl groups, including
substituted and unsubstituted alkylaryl groups, wherein the alkyl
portion of the alkylaryl group can be linear or branched, saturated
or unsaturated, and cyclic or acyclic, and wherein heteroatoms
either may or may not be present in either the aryl or the alkyl
portion of the alkylaryl group, and X and X' each, independently of
the other, is an oxygen atom or a group of the formula NR4 ,
wherein R4 is (i) a hydrogen atom, (ii) an alkyl group, including
linear and branched, saturated and unsaturated, cyclic and acyclic,
and substituted and unsubstituted alkyl groups, and wherein
heteroatoms either may or may not be present in the alkyl group,
(iii) an aryl group, including substituted and unsubstituted aryl
groups, and wherein heteroatoms either may or may not be present in
the aryl group, (iv) an arylalkyl group, including substituted and
unsubstituted arylalkyl groups, wherein the alkyl portion of the
arylalkyl group can be linear or branched, saturated or
unsaturated, and cyclic or acyclic, and wherein heteroatoms either
may or may not be present in either the aryl or the alkyl portion
of the arylalkyl group, or (v) an alkylaryl group, including
substituted and unsubstituted alkylaryl groups, wherein the alkyl
portion of the alkylaryl group can be linear or branched, saturated
or unsaturated, and cyclic or acyclic, and wherein heteroatoms
either may or may not be present in either the aryl or the alkyl
portion of the alkylaryl group.
7. An organic phase change carrier according to claim 6, wherein R2
and R2' are the same as each other and/or wherein R3 and R3' are
the same as each other.
8. An organic phase change carrier according to claim 6, wherein R3
and R3' are both alkyl groups having at least one ethylenic
unsaturation therein, including linear and branched, cyclic and
acyclic, and substituted and unsubstituted alkyl groups, and
wherein heteroatoms either may or may not be present in the alkyl
group.
9. An organic phase change carrier according to claim 1, wherein
the solid alcohol compound comprises hydrogenated castor oil.
10. An organic phase change carrier according to claim 1, wherein a
colloidal dispersion of nanoparticles is present in the organic
phase change carrier in an amount equal to or less than about 45%
by weight.
11. A phase change ink according to claim 2, wherein the phase
change inducing component is present in the organic phase change
carrier in an amount of from about 5% equal to or less than about
50% by weight.
12. An organic phase change carrier according to claim 1, wherein
the gellant is present in the organic phase change carrier in an
amount equal to or less than about 50% by weight.
13. An organic phase change carrier according to claim 1, wherein
the nanoparticles align along the network formed by the phase
change inducing agent.
14. An organic phase change carrier according to claim 1, wherein
the monomer is the reaction product of a mixture comprising (1) an
isocyanate; and (2) a component comprising (a) an alcohol having at
least one ethylenic unsaturation, and (b) an amine having at least
one ethylenic unsaturation.
15. An organic phase change carrier according to claim 1, wherein
the monomer is the reaction product of a mixture comprising (1) an
isocyanate; and (2) a component comprising an acid having at least
one ethylenic unsaturation.
16. An organic phase change carrier according to claim 12, wherein
the monomer is the reaction product of a mixture comprising (1) an
isocyanate; and (2) a component comprising an alcohol having at
least one ethylenic unsaturation.
17. An organic phase change carrier according to claim 1, wherein
the monomer is propoxylated neopentyl diacrylate, isobornyl
acrylate, isobornyl methacrylate, lauryl acrylate, lauryl
methacrylate, isodecylacrylate, isodecylmethacrylate, caprolactone
acrylate, 2-phenoxyethyl acrylate, isooctylacrylate,
isooctylmethacrylate, butyl acrylate, or mixtures thereof.
18. An organic phase change carrier according to claim 2, wherein
the monomer is the reaction product of a mixture comprising (1) an
isocyanate; and (2) a component comprising a mixture of (a) an
alcohol having at least one ethylenic unsaturation and (b) an amine
having at least one ethylenic unsaturation.
19. An organic phase change carrier according to claim 6 wherein
the monomer is the reaction product of a mixture comprising (1) an
isocyanate; and (2) a component comprising a mixture of (a) an
alcohol having at least one ethylenic unsaturation and (b) an amine
having at least one ethylenic unsaturation.
20. An organic phase change carrier according to claim 9 wherein
the monomer is the reaction product of a mixture comprising (1) an
isocyanate; and (2) a component comprising a mixture of (a) an
alcohol having at least one ethylenic unsaturation and (b) an amine
having at least one ethylenic unsaturation.
21. An organic phase change carrier according to claim 1, wherein
said nanoparticles are substantially optically transparent.
22. An organic phase change carrier according to claim 1, wherein
substantially all of said nanoparticles do not precipitate.
23. A method which comprises (a) incorporating into phase change
ink jet printing apparatus a phase change ink composition
comprising (1) an organic phase change carrier comprising (A) a
colloidal dispersion of nanoparticles exhibiting a substantially
uniform distribution of said nanoparticles discretely distributed
therewithin, and having a substantial resistance to aggregation of
said nanoparticles distributed therewithin; (B) a curable or
mixture of curable monomers; (C) a phase change inducing component
component comprising at least one of a gellant and a solid alcohol
compound; and (D) an initiator, and (2) (a) a colorant; (b) heating
the phase change ink composition to a predefined jetting
temperature; and (c) causing droplets of the liquid ink to be
ejected from said phase change ink printing apparatus in an
imagewise pattern onto a substrate to form a predetermined pattern
of ink drops, wherein said liquid ink droplets can comprise gelled
ink droplets which can be transferred from an intermediate transfer
surface to an image receiving surface for transfuse printing, said
phase change ink being capable of generating prints with good
performance in automatic document feeders.
24. A method according to claim 23, wherein the substrate is a
final recording sheet and droplets of the liquid ink are ejected in
an imagewise pattern directly onto the final recording sheet.
25. A method according to claim 23, wherein the substrate is an
intermediate transfer member and droplets of the liquid ink are
ejected in an imagewise pattern onto the intermediate transfer
member followed by transfer of the imagewise pattern from the
intermediate transfer member to a final recording sheet.
26. A method according to claim 25, wherein the intermediate
transfer member is heated to a temperature above that of the final
recording sheet and below that of the jetting temperature set point
of the printing apparatus.
27. (Currently) A method according to claim 23, wherein said phase
change ink comprises a low energy phase change ink and said phase
change ink printing apparatus is a low energy phase change ink
printing apparatus.
28. A method for producing a low energy phase change ink
composition comprising combining together (1) an organic phase
change carrier comprising (A) a colloidal dispersion of
nanoparticles, (B) a curable or mixture of curable monomers; (C) a
phase change inducing component comprising at least one of a
gellant and a solid alcohol compound; and (D) an initiator, the
carrier exhibiting a substantially uniform distribution of said
nanoparticles discretely distributed therewithin, and having a
substantial resistance to aggregation of said nanoparticles
distributed therewithin; and (2) a colorant, wherein said low
energy phase change ink can be formed into liquid droplets and
ejected from a phase change ink printing apparatus in an imagewise
pattern onto a substrate to form a predetermined pattern of ink
drops, wherein said liquid ink droplets can comprise gelled ink
droplets which can be transferred from an intermediate transfer
surface to an image receiving surface for transfuse printing, said
phase change ink being capable of generating prints with good
performance in automatic document feeders.
Description
RELATED APPLICATION
[0001] This application is a Division of co-pending U.S. patent
application Ser. No. 12/553,057, filed on Sep. 2, 2009, which is a
Division of U.S. patent application Ser. No. 11/423,777 filed on
Jun. 13, 2006, now U.S. Pat. No. 7,699,922, issued on Apr. 20,
2011, the disclosures of which are herein incorporated by reference
in its entirety.
CROSS-REFERENCE TO RELATED APPLICATIONS
[0002] Copending application U.S. Ser. No. 11/181,632, filed Jul.
13, 2005, entitled "Ink Carriers, Phase Change Inks Including Same
and Methods for Making Same," with the named inventors Adela
Goredema, Christine E. Bedford, Marcel P. Breton, and Chris A.
Wagner, the disclosure of which is totally incorporated herein by
reference, discloses an ink carrier comprising an ester terminated
oligo-amide material having a substantially low polydispersity.
This ink carrier can be combined with a colorant to produce an ink
composition.
[0003] Copending application U.S. Ser. No. 11/291,592 filed Nov.
30, 2005, entitled "Phase Change Inks and Methods for Making Same,"
with the named inventors Adela Goredema, Christine E. Bedford,
Marcel P. Breton, and Christopher A. Wagner, the disclosure of
which is totally incorporated herein by reference, discloses a
phase change ink composition and a method for forming the ink
composition. The phase change ink composition comprises (1) an ink
carrier comprising (A) a first component which comprises a
monoester wax or blend of monoesters having at least one alkyl
group comprising at least 10 carbon atoms, and (B) a second
component which comprises a polyalkylene wax, and (2) a urea
gellant, and (3) a colorant.
[0004] Copending application U.S. Ser. No. 11/291,540, filed Nov.
30, 2005, entitled "Ink Carriers Containing Nanoparticles, Phase
Change Inks Including Same and Methods for Making Same," with the
named inventors Marcel P. Breton, Adela Goredema, Christine E.
Bedford, Christopher A. Wagner, Sandra Gardner, Nan-Xing Hu, and
Bruce Goodbrand, the disclosure of which is totally incorporated
herein by reference, discloses an ink carrier and a method for
forming same, and a phase change ink including same. The ink
carrier comprises a colloidal dispersion of at least one of silica
nanoparticles and metal oxide particles. The ink carrier can also
include a low melting wax, and a gelling agent. The ink carrier
exhibits a substantially uniform distribution of the nanoparticles
so that they are discretely distributed therewithin, and are
substantially resistant to the aggregation of the nanoparticles
distributed therewithin.
[0005] Copending application U.S. Ser. No. 11/291,283, filed Nov.
30, 2005, entitled "Black Inks and Method for Making Same," with
the named inventors Marcel. P. Breton, Raymond W. Wong, Christine
E. Bedford, Christopher Wagner, and Caroline Turek, the disclosure
of which is totally incorporated herein by reference, discloses a
phase change black ink composition comprising (1) a low polarity
ink carrier comprising (A) an ester-terminated polyamide, (B) a
Guerbet alcohol or a Guerbet alcohol mixture containing at least
one linear alcohol, and (C) a low polarity wax, and (2) a black
colorant. The ink carrier can also contain a dispersant. The ink is
resistant to aggregation and settling of the black colorant when a
standby-mode printer temperature for the ink is not more than about
the gel temperature of the ink.
[0006] Copending application U.S. Ser. No. 11/291,315, filed Nov.
30, 2005, entitled "Ink Carriers, Phase Change Inks Including Same
and Methods for Making Same," with the named inventors Marcel P.
Breton, Adela Goredema, Christine E. Bedford, Christopher A.
Wagner, Stephan Drappel, Caroline Turek, Raymond W. Wong, and Nadia
Edun, the disclosure of which is totally incorporated herein by
reference, discloses an ink carrier comprising (A) an antioxidant
mixture comprising (a) a hindered phenol antioxidant, and (b) a
hindered amine antioxidant, (B) a polyalkylene wax, (C) a
functional wax, and (D) an ester-terminated amide. The low polarity
ink carrier is substantially resistant to phase separation, has
excellent thermal stability, resists autocatalytic degradation of
the ink composition and a substantial color shift upon standing,
and provides enhanced humidity resistance. This ink carrier can be
combined with a colorant to produce an ink composition.
[0007] Copending application U.S. Ser. No. 11/290,122, filed Nov.
30, 2005, entitled "Curable Amide Gellant Compounds," with the
named inventors Eniko Toma, Peter G. Odell, Adela Goredema, and
Jennifer L. Belelie, the disclosure of which is totally
incorporated herein by reference, discloses a compound of the
formula
##STR00001##
wherein R.sub.1 and R.sub.1' each, independently of the other, is
an alkyl group having at least one ethylenic unsaturation, an
arylalkyl group having at least one ethylenic unsaturation, or an
alkylaryl group having at least one ethylenic unsaturation,
R.sub.2, R.sub.2', and R.sub.3 each, independently of the others,
are alkylene groups, arylene groups, arylalkylene groups, or
alkylarylene groups, and n is an integer representing the number of
repeat amide units and is at least 1.
[0008] Copending application U.S. Ser. No. 11/289,882, filed Nov.
30, 2005, entitled "Process for Making Curable Amide Gellant
Compounds," with the named inventors Eniko Toma, Adela Goredema,
Jennifer L. Belelie, and Peter G. Odell, the disclosure of which is
totally incorporated herein by reference, discloses a process for
preparing a compound of the formula
##STR00002##
wherein R.sub.1 is an alkyl group having at least one ethylenic
unsaturation, an arylalkyl group having at least one ethylenic
unsaturation, or an alkylaryl group having at least one ethylenic
unsaturation, R.sub.2 and R.sub.3 each, independently of the
others, are alkylene groups, arylene groups, arylalkylene groups,
or alkylarylene groups, and n is an integer representing the number
of repeat amide units and is at least 1, said process comprising:
(a) reacting a diacid of the formula
HOOC--R.sub.2--COOH
with a diamine of the formula
##STR00003##
in the presence of a catalyst, a solvent, and a coupling agent to
form an oligoamide intermediate of the formula
##STR00004##
and (b) reacting the oligoamide intermediate with an alcohol of the
formula
R.sub.1--OH
to form the product.
[0009] Copending application U.S. Ser. No. 11/290,265, filed Nov.
30, 2005, entitled "Phase Change Inks," with the named inventors
Trevor J. Snyder, Bo Wu, Patricia Ann Wang, Donald R. Titterington,
Jule W. Thomas, Jr., Randall R. Bridgeman, and Mark H. Tennant, the
disclosure of which is totally incorporated herein by reference,
which discloses hot melt or phase change inks and methods for the
use thereof. More specifically, disclosed are hot melt or phase
change inks particularly suitable for use in phase change ink jet
printing processes with reduced energy requirements. One embodiment
is directed to a phase change ink composition comprising an ink
carrier and a colorant, said ink being suitable for use in an
indirect printing process wherein the ink is jetted from a
printhead onto a heated intermediate transfer member and
subsequently transferred from the intermediate transfer member to a
final recording substrate, wherein: (a) the ink can be jetted from
the printhead onto the intermediate transfer member when the ink is
maintained at a temperature of about 125.degree. C. or lower; (b)
the ink can be jetted without purging from a printer maintained at
a standby temperature of about 100.degree. C. or lower; and (c) the
ink has a cohesive failure temperature of at least about 56.degree.
C.
[0010] Copending application U.S. Ser. No. 11/301,732 filed Dec.
12, 2005, entitled "Carbon Black Inks and Method for Making Same,"
with the named inventors Raymond Wong, Marcel P. Breton, Christine
E. Bedford, Adela Goredema, and Caroline Turek, the disclosure of
which is totally incorporated herein by reference, which discloses
carbon black phase change inks and methods for making same. In one
embodiment the carbon black phase change ink composition can
comprise (1) a low polarity ink carrier comprising (A) a low
polarity wax, and optionally (B) an ester-terminated polyamide, (2)
a dispersant, and (3) a carbon black colorant.
[0011] Other copending applications include the following: U.S.
Ser. No. 11/034,866, filed Jan. 14, 2005, entitled "Radiation
Curable Inks Containing Curable Gelator Additives," with the named
inventors Marcel P. Breton et al.; U.S. Ser. No. 11/289,521, filed
Nov. 30, 2005, entitled "Curable Phase Change Compositions and
Methods for Using Such Compositions," with the named inventors
Jennifer L. Belelie et al.; U.S. Ser. No. 11/290,098, filed Nov.
30, 2005, entitled "Phase Change Inks Containing Curable
Isocyanate-derived Compounds and Phase Change Inducing Compounds,"
with the named inventors Jennifer L. Belelie et al.; U.S. Ser. No.
11/290,122, filed Nov. 30, 2005, entitled "Curable Amide Gellant
Compounds," with the named inventors Eniko Toma et al.; U.S. Ser.
No. 11/290,207, filed Nov. 30, 2005, entitled "Photoinitator with
Phase Change Properties and Gellant Affinity," with the named
inventors Peter G. Odell et al.; and U.S. Ser. No. 11/289,473,
filed Nov. 30, 2005, entitled "Radiation Curable Phase Change Inks
Containing Curable Epoxy-polyamide Composite Gellants," with the
named inventors Rina Carlini et al.
BACKGROUND
[0012] Disclosed herein are organic phase change carriers, phase
change inks and methods for making same. More specifically,
disclosed herein are organic phase change carriers and phase change
inks including nanoparticles which can be used in direct and
indirect printing processes. In one embodiment, the phase change
inks are of the low energy type. The organic phase change carriers
(1) comprise (A) a colloidal dispersion of nanoparticles, the
organic phase change carrier exhibiting a substantially uniform
distribution of said nanoparticles therewithin, with a
substantially reduced aggregation of the nanoparticles distributed
therewith. The organic phase change carrier also includes (B) at
least one curable monomer, and (C) a phase change inducing agent
and (D) an initiator. The phase change inducing agent can be at
least one of (a) a gellant or (b) a solid alcohol compound. An
embodiment of this disclosure is directed to a phase change ink
which comprises the above-described organic phase change carrier
(1) and (2) a colorant.
[0013] Another embodiment is directed to a method which comprises
(a) incorporating into an ink jet printing apparatus the
above-described phase change ink composition (b) melting the ink;
(c) causing droplets of the melted ink to be ejected in an
imagewise pattern onto an intermediate transfer member; and (d)
transferring the ink in the imagewise pattern from the intermediate
transfer member to a final recording substrate.
[0014] In general, phase change inks (sometimes referred to as "hot
melt inks") are in the solid phase at ambient temperature, but
exist in the liquid phase at the elevated operating temperature of
an ink jet printing device. At the jet operating temperature,
droplets of liquid ink are ejected from the printing device and,
when the ink droplets contact the surface of the recording
substrate, either directly or via an intermediate heated transfer
belt or drum, they quickly solidify to form a predetermined pattern
of solidified ink drops. Phase change inks have also been used in
other printing technologies, such as gravure printing, as disclosed
in, for example, U.S. Pat. No. 5,496,879 and German Patent
Publications DE 4205636AL and DE 4205713AL, the disclosures of each
of which are totally incorporated herein by reference.
[0015] Phase change inks for color printing typically comprise a
phase change organic phase change carrier composition which is
combined with a phase change ink compatible colorant. In a specific
embodiment, a series of colored phase change inks can be formed by
combining organic phase change carrier compositions with compatible
subtractive primary colorants. The subtractive primary colored
phase change inks can comprise four component dyes, namely, cyan,
magenta, yellow and black, although the inks are not limited to
these four colors. These subtractive primary colored inks can be
formed by using a single dye or a mixture of dyes. For example,
magenta can be obtained by using a mixture of Solvent Red Dyes or a
composite black can be obtained by mixing several dyes. U.S. Pat.
No. 4,889,560, U.S. Pat. No. 4,889,761, and U.S. Pat. No.
5,372,852, the disclosures of each of which are totally
incorporated herein by reference, teach that the subtractive
primary colorants employed can comprise dyes from the classes of
Color Index (commercially available from C.I.) Solvent Dyes,
Disperse Dyes, modified Acid and Direct Dyes, and Basic Dyes. The
colorants can also include pigments, as disclosed in, for example,
U.S. Pat. No. 5,221,335, the disclosure of which is totally
incorporated herein by reference. U.S. Pat. No. 5,621,022, the
disclosure of which is totally incorporated herein by reference,
discloses the use of a specific class of polymeric dyes in phase
change ink compositions.
[0016] Phase change inks have also been used for applications such
as postal marking, industrial marking, and labeling.
[0017] Phase change inks are desirable for ink jet printers because
they remain in a solid phase at room temperature during shipping,
long term storage, and the like. In addition, the problems
associated with nozzle clogging as a result of ink evaporation with
liquid ink jet inks are largely eliminated, thereby improving the
reliability of the ink jet printing. Further, in phase change ink
jet printers wherein the ink droplets are applied directly onto the
final recording substrate (for example, paper, transparency
material, and the like), the droplets solidify immediately upon
contact with the substrate, so that migration of ink along the
printing medium is prevented and dot quality is improved.
[0018] Compositions suitable for use as phase change organic phase
change carrier compositions are known and are described in U.S.
Pat. No. 6,989,052, the disclosure of which is totally incorporated
herein by reference.
[0019] U.S. Pat. No. 5,783,657, U.S. Pat. No. 5,998,570 and WO
98/17704, (Pavlin et al), the disclosures of each of which are
totally incorporated herein by reference, disclose a low molecular
weight, ester-terminated polyamide that may be blended with a
liquid hydrocarbon to form a transparent composition having gel
consistency. The ester-terminated polyamide is prepared by reacting
"x" equivalents of dicarboxylic acid wherein at least 50% of those
equivalents are from polymerized fatty acid, "y" equivalents of
diamine such as ethylene diamine, and "z" equivalents of
monoalcohol having at least 4 carbon atoms. The stoichiometry of
the reaction mixture is such that 0.9.ltoreq.{x/(y+z)}.ltoreq.1.1
and 0.1.ltoreq.{z/(y+z)}.ltoreq.0.7. The reactants are heated until
they reach reaction equilibrium.
[0020] U.S. Pat. No. 6,111,055 (Berger, et al), the disclosure of
which is totally incorporated herein by reference, discloses an
ester terminated dimer acid-based polyamide which is blended with a
solvent to form a gel. The solvent may be flammable, and a wick may
be added to the resulting gel to form a candle. The said ester
terminated dimeracid-based polyamide is prepared by thermal
condensation of a diacid, a diamine and a monoalcohol.
[0021] U.S. application Ser. No. 11/289,521 (filed Nov. 30, 2005),
the disclosure of which is totally incorporated herein by
reference, discloses a composition, comprising: (a) curable
monomer; (b) photoinitiator that initiates polymerization of said
curable monomer; and (c) phase change agent that provides the
composition with an increase in viscosity. The viscosity increase
is of at least about four orders of magnitude, from a first
temperature of from about 50.degree. C. to 130.degree. C., to a
second temperature of from about 0.degree. C. to 70.degree. C., the
second temperature being at least about 10.degree. C. below the
first temperature.
[0022] U.S. application Ser. No. 11/290,098 (filed Nov. 30, 2005),
the disclosure of which is totally incorporated herein by
reference, discloses a phase change ink comprising a colorant, an
initiator, and a phase change ink carrier, said carrier comprising
(A) a compound which is the reaction product of a mixture
comprising (1) an isocyanate; and (2) a component comprising (a) an
alcohol having at least one ethylenic unsaturation; (b) an amine
having at least one ethylenic unsaturation; (c) an acid having at
least one ethylenic unsaturation; or (d) mixtures thereof, and (B)
a phase change inducing component, said phase change inducing
component containing at least one hydroxyl group, said phase change
inducing component having a melting point of about 40.degree. C. or
higher.
[0023] U.S. application Ser. No. 11/291,540 (filed Nov. 30, 2005),
the disclosure of which is totally incorporated herein by
reference, discloses ink carriers and phase change inks including
nanoparticles which can be used in direct and indirect printing
processes. The ink carrier can also include at least one of (B) a
low melting wax, and (C) a gelling agent.
[0024] U.S. application Ser. No. 11/289,473 (filed Nov. 30, 2005),
the disclosure of which is totally incorporated herein by
reference, which is directed to a radiation curable phase change
ink which can be used in piezoelectric ink jet devices including an
ink vehicle that includes at least one curable epoxy-polyamide
gellant, and at least one colorant. The use of the gellant enables
the ink to form a gel state having a viscosity of at least 10.sup.3
mPas at very low temperatures of from about 25.degree. C. to about
100.degree. C.
[0025] U.S. application Ser. No. 11/290,122 (filed Nov. 30, 2005),
the disclosure of which is totally incorporated herein by
reference, discloses a compound of the formula
##STR00005##
wherein R.sub.1 and R.sub.1' each, independently of the other, is
an alkyl group having at least one ethylenic unsaturation, an
arylalkyl group having at least one ethylenic unsaturation, or an
alkylaryl group having at least one ethylenic unsaturation,
R.sub.2, R.sub.2', and R.sub.3 each, independently of the others,
are alkylene groups, arylene groups, arylalkylene groups, or
alkylarylene groups, and n is an integer representing the number of
repeat amide units and is at least 1.
[0026] U.S. application Ser. No. 11/290,207 (filed Nov. 30, 2005),
the disclosure of which is totally incorporated herein by
reference, discloses a compound of the formula
##STR00006##
wherein R1 is an alkylene, arylene, arylalkylene, or alkylarylene
group, R.sub.2 and R.sub.2' each, independently of the other, are
alkylene, arylene, arylalkylene, or alkylarylene groups, R.sub.3
and R.sub.3' each, independently of the other, are either (a)
photoinitiating groups, or (b) groups which are alkyl, aryl,
arylalkyl, or alkylaryl groups, provided that at least one of
R.sub.3 and R.sub.3' is a photoinitiating group, and X and X' each,
independently of the other, is an oxygen atom or a group of the
formula --NR.sub.4--, wherein R.sub.4 is a hydrogen atom, an alkyl
group, an aryl group, an arylalkyl group, or an alkylaryl
group.
[0027] Many phase change inks currently being used in solid ink jet
piezoelectric printers employ high jetting temperatures (about
140.degree. C.) and long warm up times. The images currently
produced by these inks can also, in some instances, exhibit poor
scratch resistance and image permanence.
[0028] Therefore, a need remains for improved phase change inks,
and more specifically, low energy solid inks which permit phase
change ink jet printers to perform at more moderate operating
conditions than with conventional phase change inks. For example, a
need exists for phase change inks which can be jetted at
temperatures lower than conventional jetting temperatures as
described below. Also, there is a need for phase change inks having
improved transfuse latitude and low stand-by energy. In addition, a
need remains for phase change inks which exhibit robustness, that
is resistance to scratch, crease and abrasion with substantially no
smear. There is also a need for phase change inks that can exhibit
at least some of the above advantages with reduced energy
requirements while printing. Additionally, a need remains for phase
change inks that print successfully on paper and transparency
stock. Furthermore, there is a need for phase change inks that
generate prints with good performance in automatic document
feeders.
SUMMARY
[0029] Disclosed herein is an organic phase change carrier which is
used in forming a phase change ink composition, the organic phase
change carrier comprising (A) a colloidal dispersion of at least
one of nanoparticles. The organic phase change carrier also
includes (B) at least one curable monomer, (C) a phase change
inducing agent, and (D) an initiator.
[0030] Also disclosed herein are low energy solid inks comprising
the organic phase change carrier described above. The inks exhibit
a substantially high degree of nanoparticle uniformity and a
substantially reduced degree of nanoparticle aggregation.
[0031] A method can also be provided which comprises forming the
above-described ink by combining the colloidal dispersion of
nanoparticles with other organic phase change carrier components.
Another embodiment of this disclosure is directed to a method which
comprises (a) incorporating into an ink jet printing apparatus an
ink composition comprising (1) the above-described organic phase
change carrier and (2) a colorant; (b) melting the ink; and (c)
causing droplets of the melted ink to be ejected in an imagewise
pattern onto a substrate.
DETAILED DESCRIPTION
[0032] The organic phase change carrier (1) of this disclosure
comprises (A) a colloidal dispersion of nanoparticles. The organic
phase change carrier also includes (B) at least one curable
monomer, (C) a phase change inducing agent, and (D) an initiator.
Phase change inks can comprise the above-described organic phase
change carrier (1) and (2) a colorant. The phase change ink can
have a substantially low surface energy.
[0033] Nanometer sized particles, typically in the form of a
colloidal dispersion of the nanoparticles, can be provided to
control the transfuse properties of the inks. In one embodiment,
the nanoparticles are at least one of silicon nanoparticles and
metal oxide nanoparticles. The surface properties of these
particles can be chemically modified so as to produce ink-particle
composites that have gel-like properties under specific temperature
conditions usually below the selected jetting temperature and
liquid-like properties at or above the jetting temperature. The
colloidal dispersion of the nanoparticles are combined with the
organic phase change carrier so that there is a substantially
uniform distribution of the nanoparticles within the ink matrices.
Moreover, the ink is formed with a substantially reduced
aggregation of the nanoparticles so that they are discretely
distributed.
[0034] The nanoparticles can be used as an ink stabilizer. In this
case, they can act as a nucleus for alignment of the organic phase
change carrier. In one embodiment, the nanoparticles can be aligned
along the network formed by the phase change inducing component.
This results in these inks having a unique morphology associated
with the use of nanoparticles in which they can be self aligned and
is resistant to substantial aggregation in the ink matrix. The
alignment of the particles can be along the phase separated gel
fibers and can be formed upon cooling. More particularly, the
aligning of the nanoparticles can occur within the organic phases
change carrier.
[0035] The nanoparticles can, in an embodiment herein, be dispersed
in a solvent, such as a low boiling solvent, and can then be
transferred from the solvent phase to the ink vehicles where they
are uniformly disseminated in the organic phase change carrier and
in the low energy phase change ink. The solvent can in one
embodiment be an organic solvent, and in another embodiment be a
low boiling organic solvent. These solvents in one embodiment have
a boiling point of equal to or less than about 150.degree. C., in
another embodiment have a boiling point of equal to or less than
about 130.degree. C., and in a further embodiment have a boiling
point equal to or less than about 100.degree. C., although the
boiling point can be outside of these ranges. In one embodiment
these solvents can be low boiling alcohols, glycols, glycol ethers,
glycol acetates, ketones, acetamides, and the like, as well as
mixtures thereof. In another embodiment, these solvents can be
methanol, isopropanol, ethylene glycol, ethylene glycol
mono-n-propyl ether, methyl ethyl ketone, methyl isobutyl ketone,
propylene glycol mono-methyl ether acetate, N,N-dimethyl acetamide,
and the like, as well as mixtures thereof.
[0036] In another further embodiment, silica colloidal dispersions
are commercially available from Nissan Chemicals America as
ORGANOSILICASOL.TM. compounds. In still another embodiment these
ORGANOSILICASOL.TM. compounds can include
[0037] ORGANOSILICASOL.TM. MT-ST,
[0038] ORGANOSILICASOL.TM. MA-ST-MS,
[0039] ORGANOSILICASOL.TM. IPA-ST,
[0040] ORGANOSILICASOL.TM. IPA-ST-MS,
[0041] ORGANOSILICASOL.TM. IPA-ST-L,
[0042] ORGANOSILICASOL.TM. IPA-ST-ZL,
[0043] ORGANOSILICASOL.TM. IPA-ST-UP,
[0044] ORGANOSILICASOL.TM. EG-ST,
[0045] ORGANOSILICASOL.TM. NPC-ST-30,
[0046] ORGANOSILICASOL.TM. MEK-ST,
[0047] ORGANOSILICASOL.TM. MIK-ST-MS,
[0048] ORGANOSILICASOL.TM. MIBK-ST,
[0049] ORGANOSILICASOL.TM. PMA-ST, and
[0050] ORGANOSILICASOL.TM. DMAC-ST
[0051] These low boiling solvent components respectively correspond
to the following compounds: methanol, isopropanol, ethylene glycol,
ethylene glycol mono-n-propyl ether, methyl ethyl ketone, methyl
isobutyl ketone, propylene glycol mono-methyl ether acetate, or
N,N-dimethyl acetamide.
[0052] The loading of nanoparticles in the solvent in one
embodiment is at least about 15% by weight, in another embodiment
is at least about 20% by weight, and in a further embodiment is at
least about 25% by weight, in one embodiment equal to or less than
about 45 weight percent, in another embodiment equal to or less
than about 40% by weight, and in a further embodiment equal to or
less than about 35% by weight, although the loading can be outside
of these ranges.
[0053] The nanoparticles are of any desired or effective particle
size, in one embodiment having a particle size equal to or less
than about 500 nm, in another embodiment having a particle size
equal to or less than about 300 nm, and in yet another embodiment
having a particle size equal to or less than about 100 nm, although
the particle size can be outside of these ranges.
[0054] The nanoparticles (dry-weight) are present in the organic
phase change carrier in any desired or effective amount. In one
embodiment of at least about 1% by weight of the ink, in another
embodiment of at least about 5% by weight of the ink, and in yet
another embodiment of at least about 10% by weight of the ink, and
in one embodiment equal to or less than about 40% by weight of the
ink, in another embodiment equal to or less than about 35% by
weight of the ink, and in yet another embodiment equal to or less
than about 25% by weight of the ink, although the amount can be
outside of these ranges.
[0055] In another embodiment, the nanoparticles selected can be
metal-oxide particles such as those commercially available from
Nanophase Technologies: Nano Tek.TM. Aluminum Oxide, Nano Tek.TM.
Antimony Tin Oxide and Nano Tek.TM. Zinc Oxide, the particles being
prepared by a Physical Vapor Synthesis (PVS). These particles can
be modified by Nanophase through a discrete particle encapsulation
process to enhance their dispersability in various vehicles.
[0056] In a further embodiment, the Nano Tek particles can be
modified through a sol-gel process to form particles that can be
easily dispersed in the curable phase change inks disclosed herein.
The inorganic particles can be added to a solvent such as toluene.
From about 5 and equal to or less than 20 weight % of a silicon
ester or mixture of silicon esters can be added. Mono, di and
tri-alkoxy esters can be employed. The dispersion can then be
subjected to high intensity sonication to initiate the sol-gel
chemistry. No acid or base catalyst needs to be employed as the
surface absorbed water acts to initiate hydrolysis under this high
energy acoustical agitation. Hydrolysis and condensation can then
proceed resulting in a surface passivation of the particles. After
this treatment, the particles can form an optically transparent
dispersion which shows substantially no tendency to settle.
[0057] In an additional embodiment, the Nano Tek.TM. particles are
modified to produce on the surface moieties that have strong
H-bonding capabilities. In such an embodiment these particles can
be tecton-modified nanoparticles.
[0058] In yet another embodiment, the tecton-modified nanoparticles
can be functionalized so as to contain monomer that can participate
in certain polymerization reactions such as, for example, UV or
thermally initiated polymerization processes.
[0059] The tecton structures are disclosed for example in patent
application Xerox reference A3595-US-NP, MJM Do. No. 9840-004, U.S.
application Ser. No. 11/291,540, and in Xerox U.S. Pat. Nos.
6,835,833 and 6,761,758, the disclosures of each of which are
totally incorporated herein by reference, e.g.: structure below,
where R, R.sub.1, R.sub.2, etc. are modified so as to be able to
react with the nanoparticle selected. As a variation from the
tecton structure, hydroxyethylacrylate or hydroxyethyl methacrylate
can be reacted with the isocyanate group to provide a silica
nanoparticle that participates in the cure of acrylate inks. A
version that participates in a cationic cure can also be
devised.
##STR00007##
[0060] In another embodiment, the nanoparticles are colloidal
antimonyl pentoxide surface treated particles with ethoxylated
amides, such materials being available from Nyacol Nanotehcnologies
Inc., Ashland, Mass., and sold under tradenames ADP 480 and ADP
494.
[0061] The UV curable functionalized nanoparticles can be employed
in the ink carrier disclosed herein in any desired or effective
amount, in one embodiment of at least about 0.1% by weight of the
ink, in another embodiment of at least about 5% by weight of the
ink, and in yet another embodiment of at least about 10% by weight
of the ink, and in one embodiment equal to or less than about 40%
by weight of the ink, in another embodiment equal to or less than
about 35% by weight of the ink, and in yet another embodiment equal
to or less than about 25% by weight of the ink, although the amount
can be outside of these ranges.
[0062] The organic phase change carrier can include (B) at least
one curable monomer. Examples of additional suitable ink carrier
materials include radically curable monomer compounds, such as
acrylate and methacrylate monomer compounds, which are suitable for
use as phase change ink carriers. Specific examples of relatively
nonpolar acrylate and methacrylate monomers include (but are not
limited to) isobornyl acrylate, isobornyl methacrylate, lauryl
acrylate, lauryl methacrylate, isodecylacrylate,
isodecylmethacrylate, caprolactone acrylate, 2-phenoxyethyl
acrylate, isooctylacrylate, isooctylmethacrylate, butyl acrylate,
and the like, as well as mixtures thereof. In addition,
multifunctional acrylate and methacrylate monomers and oligomers
can be included in the phase change ink carrier as reactive
diluents and as materials that can increase the crosslink density
of the cured image, thereby enhancing the toughness of the cured
images. Examples of suitable multifunctional acrylate and
methacrylate monomers and oligomers include (but are not limited
to) pentaerythritol tetraacrylate, pentaerythritol
tetramethacrylate, 1,2-ethylene glycol diacrylate, 1,2-ethylene
glycol dimethacrylate, 1,6-hexanediol diacrylate, 1,6-hexanediol
dimethacrylate, 1,12-dodecanol diacrylate, 1,12-dodecanol
dimethacrylate, tris(2-hydroxy ethyl)isocyanurate triacrylate,
propoxylated neopentyl glycol diacrylate (available from Sartomer
Co. Inc. as SR 9003), hexanediol diacrylate, tripropylene glycol
diacrylate, dipropylene glycol diacrylate, amine modified polyether
acrylates (available as PO 83 F, LR 8869, and/or LR 8889 (all
available from BASF Corporation)), trimethylolpropane triacrylate,
glycerol propoxylate triacrylate, dipentaerythritol pentaacrylate,
dipentaerythritol hexaacrylate, ethoxylated pentaerythritol
tetraacrylate (available from Sartomer Co. Inc. as SR 494), and the
like, as well as mixtures thereof. When a reactive diluent is added
to the ink carrier material, the reactive diluent is added in any
desired or effective amount, in one embodiment at least about 1
percent by weight of the carrier, and in another embodiment at
least about 35 percent by weight of the carrier, and in one
embodiment no more than about 80 percent by weight of the carrier,
and in another embodiment no more than about 70 percent by weight
of the carrier, although the amount of diluent can be outside of
these ranges.
[0063] The compounds disclosed herein are the reaction product of a
mixture comprising (1) an isocyanate; and (2) a component
comprising (a) an alcohol having at least one ethylenic
unsaturation; (b) an amine having at least one ethylenic
unsaturation; (c) an acid having at least one ethylenic
unsaturation; or (d) mixtures thereof. These reaction products can
include amides, ureas, urethanes, urea/urethanes, amide/urethanes,
and the like, as well as mixtures thereof. For example, the
reaction products of an alcohol and an isocyanate can include
urethanes. The reaction products of an amine and an isocyanate can
include ureas. The reaction products of an acid and an isocyanate
can include amides. The reaction products of an isocyanate and a
mixture of an alcohol and an amine can include urea-urethanes. The
reaction products of an isocyanate and a mixture of an acid and an
alcohol can include amide-urethanes.
[0064] Suitable isocyanates include monomeric, oligomeric, and
polymeric isocyanates, including (but are not limited to) those of
the general formula R.sub.1--(NCO).sub.n wherein R.sub.1 is (i) an
alkyl or alkylene group (including linear and branched, saturated
and unsaturated, cyclic and acyclic, and substituted and
unsubstituted alkyl and alkylene groups, and wherein heteroatoms,
such as oxygen, nitrogen, sulfur, silicon, phosphorus, and the like
either may or may not be present in the alkyl or alkylene group),
in one embodiment with at least about 8 carbon atoms, in another
embodiment with at least about 10 carbon atoms, and in yet another
embodiment with at least about 12 carbon atoms, and in one
embodiment with no more than about 60 carbon atoms, in another
embodiment with no more than about 50 carbon atoms, and in yet
another embodiment with no more than about 40 carbon atoms,
although the number of carbon atoms can be outside of these ranges,
(ii) an aryl or arylene group (including substituted and
unsubstituted aryl and arylene groups, and wherein heteroatoms,
such as oxygen, nitrogen, sulfur, silicon, phosphorus, and the like
either may or may not be present in the aryl or arylene group), in
one embodiment with at least about 5 carbon atoms, and in another
embodiment with at least about 6 carbon atoms, and in one
embodiment with no more than about 50 carbon atoms, in another
embodiment with no more than about 25 carbon atoms, and in yet
another embodiment with no more than about 12 carbon atoms,
although the number of carbon atoms can be outside of these ranges,
(iii) an arylalkyl or arylalkylene group (including substituted and
unsubstituted arylalkyl and arylalkylene groups, wherein the alkyl
portion of the arylalkyl or arylalkylene group can be linear or
branched, saturated or unsaturated, cyclic or acyclic, and
substituted or unsubstituted, and wherein heteroatoms, such as
oxygen, nitrogen, sulfur, silicon, phosphorus, and the like either
may or may not be present in either the aryl or the alkyl portion
of the arylalkyl or arylalkylene group), in one embodiment with at
least about 6 carbon atoms, and in another embodiment with at least
about 7 carbon atoms, and in one embodiment with no more than about
60 carbon atoms, in another embodiment with no more than about 40
carbon atoms, and in yet another embodiment with no more than about
30 carbon atoms, although the number of carbon atoms can be outside
of these ranges, or (iv) an alkylaryl or alkylarylene group
(including substituted and unsubstituted alkylaryl and alkylarylene
groups, wherein the alkyl portion of the alkylaryl or alkylarylene
group can be linear or branched, saturated or unsaturated, cyclic
or acyclic, and substituted or unsubstituted, and wherein
heteroatoms, such as oxygen, nitrogen, sulfur, silicon, phosphorus,
and the like either may or may not be present in either the aryl or
the alkyl portion of the alkylaryl or alkylarylene group), in one
embodiment with at least about 6 carbon atoms, and in another
embodiment with at least about 7 carbon atoms, and in one
embodiment with no more than about 60 carbon atoms, in another
embodiment with no more than about 40 carbon atoms, and in yet
another embodiment with no more than about 30 carbon atoms,
although the number of carbon atoms can be outside of these ranges,
wherein the substituents on the substituted alkyl, alkylene, aryl,
arylene, arylalkyl, arylalkylene, alkylaryl, and alkylarylene
groups can be (but are not limited to) halogen atoms, imine groups,
ammonium groups, cyano groups, pyridine groups, pyridinium groups,
ether groups, aldehyde groups, ketone groups, ester groups, amide
groups, carbonyl groups, thiocarbonyl groups, sulfate groups,
sulfonate groups, sulfide groups, sulfoxide groups, phosphine
groups, phosphonium groups, phosphate groups, nitrile groups,
mercapto groups, nitro groups, nitroso groups, sulfone groups, acyl
groups, acid anhydride groups, azide groups, azo groups, cyanato
groups, isocyanato groups, thiocyanato groups, isothiocyanato
groups, carboxylate groups, mixtures thereof, and the like, wherein
two or more substituents can be joined together to form a ring, and
n is an integer representing the number of isocyanate groups,
being, for example, 1, 2, 3, or the like in the instance of
monomeric isocyanates and having no necessary upper limit in the
case of polymeric isocyanates.
[0065] Examples of suitable isocyanates include monoisocyanates,
diisocyanates, triisocyanates, copolymers of a diisocyanate,
copolymers of a triisocyanate, polyisocyanates (having more than
three isocyanate functional groups), and the like, as well as
mixtures thereof. Examples of monoisocyanates include
n-octadecylisocyanate, of the formula
CH.sub.3--(CH.sub.2).sub.17--NCO
other isomers of octadecylisocyanate; hexadecylisocyanate;
octylisocyanate; n-butyl and t-butylisocyanate; cyclohexyl
isocyanate; adamantyl isocyanate; ethylisocyanatoacetate;
ethoxycarbonylisocyanate; phenylisocyanate; alphamethylbenzyl
isocyanate; 2-phenylcyclopropyl isocyanate; benzylisocyanate;
2-ethylphenylisocyanate; benzoylisocyanate; meta and
para-tolylisocyanate; 2-, 3-, or 4-nitrophenylisocyanates;
2-ethoxyphenyl isocyanate; 3-methoxyphenyl isocyanate;
4-methoxyphenylisocyanate; ethyl 4-isocyanatobenzoate;
2,6-dimethylphenylisocyante; 1-naphthylisocyanate;
(naphthyl)ethylisocyantes; and the like, as well as mixtures
thereof. Examples of diisocyanates include isophorone diisocyanate
(PDT), of the formula
##STR00008##
toluene diisocyanate (TDI); diphenylmethane-4,4'-diisocyanate
(MDI); hydrogenated diphenylmethane-4,4'-diisocyanate (H12MDI);
tetra-methyl xylene diisocyanate (TMXDI);
hexamethylene-1,6-diisocyanate (HDI), of the formula
OCN--(CH.sub.2).sub.6--NCO
naphthalene-1,5-diisocyanate;
3,3'-dimethoxy-4,4'-biphenyldiisocyanate;
3,3'-dimethyl-4,4'-bimethyl-4,4'-biphenyldiisocyanate; phenylene
diisocyanate; 4,4'-biphenyldiisocyanate;
2,2,4-trimethylhexamethylene diisocyanate and
2,4,4-trimethylhexamethylene diisocyanate, of the formulae
##STR00009##
tetramethylene xylene diisocyanate;
4,4'-methylenebis(2,6-diethylphenyl isocyanate);
1,12-diisocyanatododecane; 1,5-diisocyanato-2-methylpentane;
1,4-diisocyanatobutane; dimer diisocyanate and cyclohexylene
diisocyanate and its isomers; uretidione dimers of HDI; and the
like, as well as mixtures thereof. Examples of triisocyanates or
their equivalents include the trimethylolpropane trimer of TDI, and
the like, isocyanurate trimers of TDI, HDI, IPDI, and the like, and
biuret trimers of TDI, HDI, IPDI, and the like, as well as mixtures
thereof. Examples of higher isocyanate functionalities include
copolymers of TDUHDI, and the like, and MDI oligomers, as well as
mixtures thereof.
[0066] Examples of suitable acids include any ethylenically
unsaturated acid, including (but not limited to) those of the
formula R.sub.2--COOH wherein R.sub.2 is (i) an alkyl group having
at least one ethylenic unsaturation therein (including linear and
branched, cyclic and acyclic, and substituted and unsubstituted
alkyl groups, and wherein heteroatoms, such as oxygen, nitrogen,
sulfur, silicon, phosphorus, and the like either may or may not be
present in the alkyl group), in one embodiment with at least about
2 carbon atoms, in another embodiment with at least about 4 carbon
atoms, in yet another embodiment with at least about 6 carbon
atoms, and in still another embodiment with at least about 10
carbon atoms, and in one embodiment with no more than about 40
carbon atoms, in another embodiment with no more than about 30
carbon atoms, in yet another embodiment with no more than about 22
carbon atoms, and in still another embodiment with no more than
about 11 carbon atoms, although the number of carbon atoms can be
outside of these ranges, (ii) an arylalkyl group having at least
one ethylenic unsaturation therein (including substituted and
unsubstituted arylalkyl groups, wherein the alkyl portion of the
arylalkyl group can be linear or branched, cyclic or acyclic, and
substituted or unsubstituted, and wherein heteroatoms, such as
oxygen, nitrogen, sulfur, silicon, phosphorus, and the like either
may or may not be present in either the aryl or the alkyl portion
of the arylalkyl group), in one embodiment with at least about 6
carbon atoms, and in another embodiment with at least about 7
carbon atoms, and in one embodiment with no more than about 50
carbon atoms, in another embodiment with no more than about 25
carbon atoms, and in yet another embodiment with no more than about
12 carbon atoms, although the number of carbon atoms can be outside
of these ranges, or (iii) an alkylaryl group having at least one
ethylenic unsaturation therein (including substituted and
unsubstituted alkylaryl groups, wherein the alkyl portion of the
alkylaryl group can be linear or branched, cyclic or acyclic, and
substituted or unsubstituted, and wherein heteroatoms, such as
oxygen, nitrogen, sulfur, silicon, phosphorus, and the like either
may or may not be present in either the aryl or the alkyl portion
of the alkylaryl group), in one embodiment with at least about 6
carbon atoms, and in another embodiment with at least about 7
carbon atoms, and in one embodiment with no more than about 50
carbon atoms, in another embodiment with no more than about 25
carbon atoms, and in yet another embodiment with no more than about
12 carbon atoms, although the number of carbon atoms can be outside
of these ranges, wherein the substituents on the substituted alkyl,
arylalkyl, and alkylaryl groups can be (but are not limited to)
hydroxy groups, halogen atoms, imine groups, ammonium groups, cyano
groups, pyridine groups, pyridinium groups, ether groups, aldehyde
groups, ketone groups, ester groups, amide groups, carbonyl groups,
thiocarbonyl groups, sulfate groups, sulfonate groups, sulfonic
acid groups, sulfide groups, sulfoxide groups, phosphine groups,
phosphonium groups, phosphate groups, nitrile groups, mercapto
groups, nitro groups, nitroso groups, sulfone groups, acyl groups,
acid anhydride groups, azide groups, azo groups, cyanato groups,
thiocyanato groups, isothiocyanato groups, carboxylate groups,
carboxylic acid groups, urethane groups, urea groups, mixtures
thereof, and the like, wherein two or more substituents can be
joined together to form a ring.
[0067] Some specific examples of suitable ethylenically unsaturated
acids include 10-undecenoic acid, of the formula
##STR00010##
21-docosenoic acid, 6-heptenoic acid, 2,2-dimethyl-4-pentenoic
acid, 2,2-dimethyl-but-3-enoic acid, acrylic acid, methacrylic
acid, 3-butenoic acid, 3,7-dimethyl-6-octenoic acid, crotonic acid,
9-decenoic acid, 3-hexenoic acid, 2-methyl-3-butenoic acid,
7-oxo-11-dodecenoic acid, 7-oxo16-heptadecenoic acid,
6-oxo-15-hexadecenoic acid, 7-oxo-8-nonenoic acid, 4-pentenoic
acid, and the like, as well as mixtures thereof.
[0068] If desired, a mixture of acids including an ethylenically
unsaturated acid and an acid containing no ethylenic unsaturations
can be used in the reaction with the isocyanate. By so doing, the
characteristics of the product can be further tailored as desired.
For example, the ethylenically unsaturated acid can impart to the
product curability, when in the presence of one or more suitable
photoinitiators, upon exposure to ultraviolet radiation, while the
acid containing no ethylenic unsaturations can impart to the
product desirable solubility characteristics.
[0069] Examples of suitable alcohols include any ethylenically
unsaturated alcohol, including (but not limited to) those of the
formula R.sub.3--OH wherein R.sub.3 is (i) an alkyl group having at
least one ethylenic unsaturation therein (including linear and
branched, cyclic and acyclic, and substituted and unsubstituted
alkyl groups, and wherein heteroatoms, such as oxygen, nitrogen,
sulfur, silicon, phosphorus, and the like either may or may not be
present in the alkyl group), in one embodiment with at least about
5 carbon atoms, in another embodiment with at least about 8 carbon
atoms, and in yet another embodiment with at least about 12 carbon
atoms, and in one embodiment with no more than about 50 carbon
atoms, in another embodiment with no more than about 30 carbon
atoms, and in yet another embodiment with no more than about 15
carbon atoms, although the number of carbon atoms can be outside of
these ranges, (ii) an arylalkyl group having at least one ethylenic
unsaturation therein (including substituted and unsubstituted
arylalkyl groups, wherein the alkyl portion of the arylalkyl group
can be linear or branched, cyclic or acyclic, and substituted or
unsubstituted, and wherein heteroatoms, such as oxygen, nitrogen,
sulfur, silicon, phosphorus, and the like either may or may not be
present in either the aryl or the alkyl portion of the arylalkyl
group), in one embodiment with at least about 6 carbon atoms, and
in another embodiment with at least about 7 carbon atoms, and in
one embodiment with no more than about 50 carbon atoms, in another
embodiment with no more than about 25 carbon atoms, and in yet
another embodiment with no more than about 12 carbon atoms,
although the number of carbon atoms can be outside of these ranges,
or (iii) an alkylaryl group having at least one ethylenic
unsaturation therein (including substituted and unsubstituted
alkylaryl groups, wherein the alkyl portion of the alkylaryl group
can be linear or branched, cyclic or acyclic, and substituted or
unsubstituted, and wherein heteroatoms, such as oxygen, nitrogen,
sulfur, silicon, phosphorus, and the like either may or may not be
present in either the aryl or the alkyl portion of the alkylaryl
group), in one embodiment with at least about 6 carbon atoms, and
in another embodiment with at least about 7 carbon atoms, and in
one embodiment with no more than about 50 carbon atoms, in another
embodiment with no more than about 25 carbon atoms, and in yet
another embodiment with no more than about 12 carbon atoms,
although the number of carbon atoms can be outside of these ranges,
wherein the substituents on the substituted alkyl, arylalkyl, and
alkylaryl groups can be (but are not limited to) hydroxy groups,
amine groups, halogen atoms, imine groups, ammonium groups, cyano
groups, pyridine groups, pyridinium groups, ether groups, aldehyde
groups, ketone groups, ester groups, amide groups, carbonyl groups,
thiocarbonyl groups, sulfate groups, sulfonate groups, sulfonic
acid groups, sulfide groups, sulfoxide groups, phosphine groups,
phosphonium groups, phosphate groups, nitrile groups, mercapto
groups, nitro groups, nitroso groups, sulfone groups, acyl groups,
acid anhydride groups, azide groups, azo groups, cyanato groups,
thiocyanato groups, isothiocyanato groups, carboxylate groups,
carboxylic acid groups, urethane groups, urea groups, mixtures
thereof, and the like, wherein two or more substituents can be
joined together to form a ring.
[0070] Some specific examples of suitable ethylenically unsaturated
alcohols include 1,4-butanediol vinyl ether, of the formula
HO--(CH.sub.2).sub.4--O--CH.dbd.CH.sub.2
available from Sigma-Aldrich, Milwaukee, Wis., 2-allyloxyethanol,
of the formula
HO--(CH.sub.2).sub.2--CH.sub.2CH.dbd.CH.sub.2
1,4-cyclohexanedimethanol vinyl ether (cis and trans isomers), of
the formula
##STR00011##
ethylene glycol vinyl ether, of the formula
##STR00012##
di(ethylene glycol)vinyl ether, of the formula
##STR00013##
TONE M-100, commercially available from Dow Chemical Company,
Midland, Mich., believed to be of the formula
##STR00014##
compounds of the formula
##STR00015##
such as CD572, wherein n=10, commercially available from Sartomer
Company, Exton, Pa., and the like, as well as mixtures thereof.
[0071] If desired, a mixture of alcohols including an ethylenically
unsaturated alcohol and an alcohol containing no ethylenic
unsaturations can be used in the reaction with the isocyanate. By
so doing, the characteristics of the product can be further
tailored as desired. For example, the ethylenically unsaturated
alcohol can impart to the product curability, when in the presence
of one or more suitable photoinitiators, upon exposure to
ultraviolet radiation, while the alcohol containing no ethylenic
unsaturations can impart to the product desirable solubility
characteristics.
[0072] Examples of suitable amines include any ethylenically
unsaturated primary or secondary amine, including (but not limited
to) those of the formula R.sub.4--NHR.sub.5 wherein R.sub.4 is (i)
an alkyl group having at least one ethylenic unsaturation therein
(including linear and branched, cyclic and acyclic, and substituted
and unsubstituted alkyl groups, and wherein heteroatoms, such as
oxygen, nitrogen, sulfur, silicon, phosphorus, and the like either
may or may not be present in the alkyl group), in one embodiment
with at least about 5 carbon atoms, in another embodiment with at
least about 8 carbon atoms, and in yet another embodiment with at
least about 12 carbon atoms, and in one embodiment with no more
than about 50 carbon atoms, in another embodiment with no more than
about 30 carbon atoms, and in yet another embodiment with no more
than about 15 carbon atoms, although the number of carbon atoms can
be outside of these ranges, (ii) an arylalkyl group having at least
one ethylenic unsaturation therein (including substituted and
unsubstituted arylalkyl groups, wherein the alkyl portion of the
arylalkyl group can be linear or branched, cyclic or acyclic, and
substituted or unsubstituted, and wherein heteroatoms, such as
oxygen, nitrogen, sulfur, silicon, phosphorus, and the like either
may or may not be present in either the aryl or the alkyl portion
of the arylalkyl group), in one embodiment with at least about 6
carbon atoms, and in another embodiment with at least about 7
carbon atoms, and in one embodiment with no more than about 50
carbon atoms, in another embodiment with no more than about 25
carbon atoms, and in yet another embodiment with no more than about
12 carbon atoms, although the number of carbon atoms can be outside
of these ranges, or (iii) an alkylaryl group having at least one
ethylenic unsaturation therein (including substituted and
unsubstituted alkylaryl groups, wherein the alkyl portion of the
alkylaryl group can be linear or branched, cyclic or acyclic, and
substituted or unsubstituted, and wherein heteroatoms, such as
oxygen, nitrogen, sulfur, silicon, phosphorus, and the like either
may or may not be present in either the aryl or the alkyl portion
of the alkylaryl group), in one embodiment with at least about 6
carbon atoms, and in another embodiment with at least about 7
carbon atoms, and in one embodiment with no more than about 50
carbon atoms, in another embodiment with no more than about 25
carbon atoms, and in yet another embodiment with no more than about
12 carbon atoms, although the number of carbon atoms can be outside
of these ranges, and wherein R.sub.5 can be (i) a hydrogen atom,
(ii) an alkyl group (including linear and branched, saturated and
unsaturated, cyclic and acyclic, and substituted and unsubstituted
alkyl groups, and wherein heteroatoms, such as oxygen, nitrogen,
sulfur, silicon, phosphorus, and the like either may or may not be
present in the alkyl group), in one embodiment with at least 1
carbon atom, and in one embodiment with no more than about 50
carbon atoms, in another embodiment with no more than about 30
carbon atoms, and in yet another embodiment with no more than about
15 carbon atoms, although the number of carbon atoms can be outside
of these ranges, (iii) an aryl group (including substituted and
unsubstituted aryl groups, and wherein heteroatoms, such as oxygen,
nitrogen, sulfur, silicon, phosphorus, and the like either may or
may not be present in the aryl group), in one embodiment with at
least about 5 carbon atoms, and in another embodiment with at least
about 6 carbon atoms, and in one embodiment with no more than about
50 carbon atoms, in another embodiment with no more than about 30
carbon atoms, and in yet another embodiment with no more than about
15 carbon atoms, although the number of carbon atoms can be outside
of these ranges, (iv) an arylalkyl group (including substituted and
unsubstituted arylalkyl groups, wherein the alkyl portion of the
arylalkyl group can be linear or branched, saturated or
unsaturated, cyclic or acyclic, and substituted or unsubstituted,
and wherein heteroatoms, such as oxygen, nitrogen, sulfur, silicon,
phosphorus, and the like either may or may not be present in either
the aryl or the alkyl portion of the arylalkyl group), in one
embodiment with at least about 6 carbon atoms, and in another
embodiment with at least about 7 carbon atoms, and in one
embodiment with no more than about 50 carbon atoms, in another
embodiment with no more than about 30 carbon atoms, and in yet
another embodiment with no more than about 15 carbon atoms,
although the number of carbon atoms can be outside of these ranges,
or (v) an alkylaryl group (including substituted and unsubstituted
alkylaryl groups, wherein the alkyl portion of the alkylaryl group
can be linear or branched, saturated or unsaturated, cyclic or
acyclic, and substituted or unsubstituted, and wherein heteroatoms,
such as oxygen, nitrogen, sulfur, silicon, phosphorus, and the like
either may or may not be present in either the aryl or the alkyl
portion of the alkylaryl group), in one embodiment with at least
about 6 carbon atoms, and in another embodiment with at least about
7 carbon atoms, and in one embodiment with no more than about 50
carbon atoms, in another embodiment with no more than about 30
carbon atoms, and in yet another embodiment with no more than about
15 carbon atoms, although the number of carbon atoms can be outside
of these ranges, wherein the substituents on the substituted alkyl,
aryl, arylalkyl, and alkylaryl groups can be (but are not limited
to) hydroxy groups, amine groups, halogen atoms, imine groups,
ammonium groups, cyano groups, pyridine groups, pyridinium groups,
ether groups, aldehyde groups, ketone groups, ester groups, amide
groups, carbonyl groups, thiocarbonyl groups, sulfate groups,
sulfonate groups, sulfonic acid groups, sulfide groups, sulfoxide
groups, phosphine groups, phosphonium groups, phosphate groups,
nitrile groups, mercapto groups, nitro groups, nitroso groups,
sulfone groups, acyl groups, acid anhydride groups, azide groups,
azo groups, cyanato groups, thiocyanato groups, isothiocyanato
groups, carboxylate groups, urethane groups, urea groups, mixtures
thereof, and the like, wherein two or more substituents can be
joined together to form a ring.
[0073] Examples of suitable amines include
2(1-cyclohexenyl)ethylamine, commercially available from
Sigma-Aldrich Chemical Co., Milwaukee, Wis., of the formula
##STR00016##
N-ethyl-2-methylallylamine, commercially available from
Sigma-Aldrich Chemical Co., Milwaukee, Wis., of the formula
##STR00017##
monoethanolamine vinyl ether, commercially available from Alash
Ltd., Temirtau, Kazakhstan, of the formula
##STR00018##
and the like.
[0074] If desired, a mixture of amines including an ethylenically
unsaturated amine and an amine containing no ethylenic
unsaturations can be used in the reaction with the isocyanate. By
so doing, the characteristics of the product can be further
tailored as desired. For example, the ethylenically unsaturated
amine can impart to the product curability, when in the presence of
one or more suitable photoinitiators, upon exposure to ultraviolet
radiation, while the amine containing no ethylenic unsaturations
can impart to the product desirable solubility characteristics.
[0075] Additionally, hydroxyl/amino containing compounds can be
employed (with di- and higher functionality isocyanates taking
advantage of the difference in reactivity of the amine over the
hydroxyl group, or with monoisocyanates reacting with the amine
preferentially or with both the amine and the hydroxyl groups).
Examples of these compounds include ethanolamine, diethanolamine,
and the like.
[0076] Any suitable reaction conditions for making urethane, urea,
or urethane/urea compounds by condensing alcohols and/or amines
with isocyanates can be used to prepare the urethane, urea,
urea-urethane, or amide-urethane compounds. Typically (although not
necessarily), the reaction is carried out at elevated temperatures
(for example, from about 45 to about 160.degree. C.) in the
presence of an optional reaction catalyst, such as dibutyltin
dilaurate, bismuth tris-neodecanoate, cobalt benzoate, lithium
acetate, stannous octoate, triethylamine, or the like. In a
specific embodiment, the reaction conditions are conducted in an
inert atmosphere, such as argon or nitrogen gas or other suitable
gases, to prevent oxidizing or yellowing of the reaction products
and to prevent undesirable side reactions. The reaction can employ
an inert solvent, such as toluene or the like, or can be performed
neat (i.e., without a solvent). The mole ratio of reactants is
adjusted so that the isocyanate functionalities are completely
consumed in the reaction with a slight molar excess of alcohol
and/or amine typically remaining. The reactants can be added
together in any order and/or added to the reaction as physical
mixtures. If desired, reaction conditions and the order of the
addition of reactants can be controlled for several reasons, such
as to provide a controlled exothermic reaction, to tailor the
distribution of molecules when reacting a diisocyanate with a
mixture of an alcohol and an amine, or the like. When doing these
adjustments, the different reactivities to isocyanates of alcohols
versus amines can be employed, as well as the different
reactivities of the two separate isocyanate groups on diisocyanates
such as isophorone diisocyanate. See, for example, J. H. Saunders
and K. C. Frisch's "Polyurethanes Part I, Chemistry" published by
Interscience of New York, N.Y. in 1962 and Olin Chemicals'
LUXATE.RTM. IM isophorone diisocyanate technical product
information sheet, the disclosures of each of which are totally
incorporated herein by reference, which provide further explanation
of this chemistry. By so tailoring the distribution of molecules,
one can control the finished product to have a controlled viscosity
that is designed for a specific application, have a controlled
glass transition temperature and/or melting point, have consistent
properties from batch to batch, or the like.
[0077] The reaction can be carried out either neat or, optionally,
in the presence of a solvent. When present, any desired or
effective solvent can be used. Examples of suitable solvents
include xylene, toluene, benzene, chlorobenzene, nitrobenzene,
dichlorobenzene, N-methyl pyrrolidinone, dimethyl formamide,
dimethyl sulfoxide, sulfolane, hexane, tetrahydrofuran, and the
like, as well as mixtures thereof.
[0078] Reactions wherein isocyanates are reacted with alcohols,
amines, and acids to form urethanes, ureas, and amides are also
disclosed in, for example, U.S. application Ser. No. 10/260,146
(U.S. Publication 20040077887), U.S. Pat. No. 6,821,327, U.S.
application Ser. No. 10/260,379 (U.S. Publication 20040082801),
Ser. No. 10/369,981 (U.S. Publication 20040167249), Ser. Nos.
10/918,053, and 10/918,619, the disclosures of each of which are
totally incorporated herein by reference.
[0079] The organic phase change carrier can include (C) a phase
change inducing component. This component is referred to as a phase
change inducing component because it influences the phase change
transition temperature. The phase change inducing component is
miscible with the other ink components and is a solid at the drum
temperature at the time when the ink is jetted onto the drum in
embodiments when the ink is used in printing processes wherein the
substrate is an intermediate transfer member, and is a solid at the
temperature of the final recording sheet in embodiments when the
substrate is a final recording sheet. The phase change inducing
component is a molecule with at least one hydroxyl group and has a
minimum melting point of about 40.degree. C. Examples of suitable
phase change inducing components include (but are not limited to)
alcohols of the formula Rc-OH wherein R.sub.c is (i) an alkyl group
(including linear and branched, cyclic and acyclic, and substituted
and unsubstituted alkyl groups, and wherein heteroatoms, such as
oxygen, nitrogen, sulfur, silicon, phosphorus, and the like either
may or may not be present in the alkyl group), in one embodiment
with at least about 1 carbon atom, in another embodiment with at
least about 5 carbon atoms, in yet another embodiment with at least
about 10 carbon atoms, and in still another embodiment with at
least about 15 carbon atoms, and in one embodiment with no more
than about 100 carbon atoms, in another embodiment with no more
than about 80 carbon atoms, and in yet another embodiment with no
more than about 60 carbon atoms, although the number of carbon
atoms can be outside of these ranges, (ii) an aryl group (including
substituted and unsubstituted aryl groups, and wherein heteroatoms,
such as oxygen, nitrogen, sulfur, silicon, phosphorus, and the like
either may or may not be present in the aryl group), in one
embodiment with at least about 5 carbon atoms, in another
embodiment with at least about 6 carbon atoms, and in yet another
embodiment with at least about 10 carbon atoms, and in one
embodiment with no more than about 50 carbon atoms, in another
embodiment with no more than about 25 carbon atoms, and in yet
another embodiment with no more than about 12 carbon atoms,
although the number of carbon atoms can be outside of these ranges,
(iii) an arylalkyl group (including substituted and unsubstituted
arylalkyl groups, wherein the alkyl portion of the arylalkyl group
can be linear or branched, cyclic or acyclic, and substituted or
unsubstituted, and wherein heteroatoms, such as oxygen, nitrogen,
sulfur, silicon, phosphorus, and the like either may or may not be
present in either the aryl or the alkyl portion of the arylalkyl
group), in one embodiment with at least about 6 carbon atoms, and
in another embodiment with at least about 7 carbon atoms, and in
one embodiment with no more than about 50 carbon atoms, in another
embodiment with no more than about 25 carbon atoms, and in yet
another embodiment with no more than about 12 carbon atoms,
although the number of carbon atoms can be outside of these ranges,
or (iv) an alkylaryl group (including substituted and unsubstituted
alkylaryl groups, wherein the alkyl portion of the alkylaryl group
can be linear or branched, cyclic or acyclic, and substituted or
unsubstituted, and wherein heteroatoms, such as oxygen, nitrogen,
sulfur, silicon, phosphorus, and the like either may or may not be
present in either the aryl or the alkyl portion of the alkylaryl
group), in one embodiment with at least about 6 carbon atoms, and
in another embodiment with at least about 7 carbon atoms, and in
one embodiment with no more than about 50 carbon atoms, in another
embodiment with no more than about 25 carbon atoms, and in yet
another embodiment with no more than about 12 carbon atoms,
although the number of carbon atoms can be outside of these ranges,
wherein the substituents on the substituted alkyl, arylalkyl, and
alkylaryl groups can be (but are not limited to) hydroxy groups,
halogen atoms, imine groups, ammonium groups, cyano groups,
pyridine groups, pyridinium groups, ether groups, aldehyde groups,
ketone groups, ester groups, amide groups, carbonyl groups,
thiocarbonyl groups, sulfate groups, sulfonate groups, sulfide
groups, sulfoxide groups, phosphine groups, phosphonium groups,
phosphate groups, nitrile groups, mercapto groups, nitro groups,
nitroso groups, sulfone groups, acyl groups, acid anhydride groups,
azide groups, azo groups, cyanato groups, isocyanato groups,
thiocyanato groups, isothiocyanato groups, carboxylate groups,
mixtures thereof, and the like, wherein two or more substituents
can be joined together to form a ring.
[0080] Specific examples of suitable phase change inducing alcohols
include 1,10-decanediol, commercially available from Sigma-Aldrich,
Milwaukee, Wis., 1,12-dodecanediol, commercially available from
Sigma-Aldrich, 1,2-dodecanediol, commercially available from
Sigma-Aldrich, UNILINO 350, 425, 550, and 700, which are mixtures
of linear primary alcohols with average molecular weights of about
350, 425, 550, and 700, respectively, commercially available from
Baker Petrolite, Sand Springs, Okla., polycaprolactone diols, of
the general formula
##STR00019##
including those having M.sub.n values of about 530, 1,250, and
2,000, commercially available from Sigma-Aldrich, polycaprolactone
diols, of the general formula
##STR00020##
including those having M.sub.n values of about 300 and 900,
commercially available from Sigma-Aldrich, heptadecanol (all
isomers), octadecanol (all isomers), nonadecanol (all isomers),
eicosanol (C.sub.20H.sub.41OH; all isomers), heneicosanol
(C.sub.21H.sub.43OH; all isomers), docosanol (C.sub.22H.sub.45OH;
all isomers), dimer diols believed to be of the formula
HO--C.sub.36H.sub.64+n--OH wherein C.sub.36H.sub.64+n is a branched
alkylene group which may include unsaturations and cyclic groups,
wherein n is an integer of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10,
including but not limited to isomers of the formulae
##STR00021##
commercially available from Uniqema Chemicals, New Castle, Del.,
Guerbet alcohols, which are 2,2-dialkyl-1-ethanols, including (but
not limited to) those of the general formula
##STR00022##
wherein m+n is greater than or equal to 10, in one embodiment being
from about 16 to about 36, commercially available from Tomah
Chemicals and Jarchem Industries Inc., Newark, N.J., and the like,
as well as mixtures thereof.
[0081] One specific example of a phase change inducing component is
hydrogenated castor oil, a trial triester believed to be of the
formula
##STR00023##
[0082] The phase change inducing component is present in the phase
change ink carrier in any desired or effective amount effective to
influence the phase change transition temperature, in one
embodiment at least about 5 percent by weight of the carrier, in
another embodiment at least about 7.5 percent by weight of the
carrier, in yet another embodiment at least about 10 percent by
weight of the carrier, and in still another embodiment at least
about 20 percent by weight of the carrier, and in one embodiment no
more than about 98 percent by weight of the carrier, in another
embodiment no more than about 80 percent by weight of the carrier,
in yet another embodiment no more than about 60 percent by weight
of the carrier, in still another embodiment no more than about 50
percent by weight of the carrier, and in another embodiment no more
than about 30 percent by weight of the carrier, although the amount
can be outside of these ranges.
[0083] The organic phase change carrier may also include (D) an
initiator. The ink compositions further contain an initiator.
[0084] Examples of free radical initiators include benzyl ketones,
monomeric hydroxyl ketones, polymeric hydroxyl ketones, a-amino
ketones, acyl phosphine oxides, metallocenes, benzophenone,
benzophenone derivatives, and the like. Specific examples include
1-hydroxycyclohexylphenylketone, benzophenone,
2-benzyl-2-(dimethylamino)-1-(4-(4-morphorlinyl)phenyl)-1-butanone,
2-methyl-I-(4-methylthio)phenyl-2-(4-morphorlinyl)-1-propanone,
diphenyl-(2,4,6-trimethylbenzoyl)phosphine oxide, phenyl
bis(2,4,6-trimethylbenzoyl)phosphine oxide, benzyl-dimethylketal,
isopropylthioxanthone, and the like, as well as mixtures
thereof.
[0085] Examples of cationic initiators include aryldiazonium salts,
diaryliodonium salts, triaylsulfonium salts, triarylselenonium
salts, dialkylphenacylsulfonium salts, triarylsulfoxonium salts,
aryloxydiarylsulfonium salts, and the like. Specific examples
include triphenylsulfonium hexaflurophosphate,
methyldiphenylsulfonium hexafluorophosphate,
dimethylphenylsulfonium hexaflurophosphate,
diphenylnapththylsulfonium hexaflurophosphate,
di(methoxynapththyl)methylsulfonium hexaflurophosphate,
(4-octyloxyphenyl)phenyl iodonium hexafluoroantimonate,
(4-octyloxyphenyl)diphenyl sulfonium hexafluoroantimonate,
(4-decyloxyphenyl)phenyl iodonium hexafluoroantimonite,
(4-dodecyloxyphenyl)diphenyl sulfonium hexafluoroantimonate, and
the like, as well as mixtures thereof.
[0086] The initiator is present in the phase change ink carrier in
any desired or effective amount, in one embodiment at least about
0.1 percent by weight of the carrier, in another embodiment at
least about 1 percent by weight of the carrier, in yet another
embodiment at least about 5 percent by weight of the carrier, and
in still another embodiment at least about 10 percent by weight of
the carrier, and in one embodiment no more than about 20 percent by
weight of the carrier, in another embodiment no more than about 17
percent by weight of the carrier, and in yet another embodiment no
more than about 15 percent by weight of the carrier, although the
amount can be outside of these ranges.
[0087] In one embodiment, the phase change inducing component can
comprise at least one of a gellant and an alcohol compound. In
another embodiment, the gellant is compounds of the formula
##STR00024##
wherein:
[0088] R.sub.1 is: [0089] (i) an alkylene group (wherein an
alkylene group is defined as a divalent aliphatic group or alkyl
group, including linear and branched, saturated and unsaturated,
cyclic and acyclic, and substituted and unsubstituted alkylene
groups, and wherein heteroatoms, such as oxygen, nitrogen, sulfur,
silicon, phosphorus, boron, and the like either may or may not be
present in the alkylene group), in one embodiment with at least 1
carbon atom, and in one embodiment with no more than about 12
carbon atoms, in another embodiment with no more than about 4
carbon atoms, and in yet another embodiment with no more than about
2 carbon atoms, although the number of carbon atoms can be outside
of these ranges, [0090] (ii) an arylene group (wherein an arylene
group is defined as a divalent aromatic group or aryl group,
including substituted and unsubstituted arylene groups, and wherein
heteroatoms, such as oxygen, nitrogen, sulfur, silicon, phosphorus,
boron, and the like either may or may not be present in the arylene
group), in one embodiment with at least about 5 carbon atoms, and
in another embodiment with at least about 6 carbon atoms, and in
one embodiment with no more than about 14 carbon atoms, in another
embodiment with no more than about 10 carbon atoms, and in yet
another embodiment with no more than about 6 carbon atoms, although
the number of carbon atoms can be outside of these ranges, [0091]
(iii) an arylalkylene group (wherein an arylalkylene group is
defined as a divalent arylalkyl group, including substituted and
unsubstituted arylalkylene groups, wherein the alkyl portion of the
arylalkylene group can be linear or branched, saturated or
unsaturated, and cyclic or acyclic, and wherein heteroatoms, such
as oxygen, nitrogen, sulfur, silicon, phosphorus, boron, and the
like either may or may not be present in either the aryl or the
alkyl portion of the arylalkylene group), in one embodiment with at
least about 6 carbon atoms, and in another embodiment with at least
about 7 carbon atoms, and in one embodiment with no more than about
32 carbon atoms, in another embodiment with no more than about 22
carbon atoms, and in yet another embodiment with no more than about
7 carbon atoms, although the number of carbon atoms can be outside
of these ranges, or [0092] (iv) an alkylarylene group (wherein an
alkylarylene group is defined as a divalent alkylaryl group,
including substituted and unsubstituted alkylarylene groups,
wherein the alkyl portion of the alkylarylene group can be linear
or branched, saturated or unsaturated, and cyclic or acyclic, and
wherein heteroatoms, such as oxygen, nitrogen, sulfur, silicon,
phosphorus, boron, and the like either may or may not be present in
either the aryl or the alkyl portion of the alkylarylene group), in
one embodiment with at least about 6 carbon atoms, and in another
embodiment with at least about 7 carbon atoms, and in one
embodiment with no more than about 32 carbon atoms, in another
embodiment with no more than about 22 carbon atoms, and in yet
another embodiment with no more than about 7 carbon atoms, although
the number of carbon atoms can be outside of these ranges, wherein
the substituents on the substituted alkylene, arylene,
arylalkylene, and alkylarylene groups can be (but are not limited
to) halogen atoms, cyano groups, pyridine groups, pyridinium
groups, ether groups, aldehyde groups, ketone groups, ester groups,
amide groups, carbonyl groups, thiocarbonyl groups, sulfide groups,
nitro groups, nitroso groups, acyl groups, azo groups, urethane
groups, urea groups, mixtures thereof, and the like, wherein two or
more substituents can be joined together to faun a ring;
[0093] R.sub.2 and R.sub.2' each, independently of the other, are:
[0094] (i) alkylene groups (wherein an alkylene group is defined as
a divalent aliphatic group or alkyl group, including linear and
branched, saturated and unsaturated, cyclic and acyclic, and
substituted and unsubstituted alkylene groups, and wherein
heteroatoms, such as oxygen, nitrogen, sulfur, silicon, phosphorus,
boron, and the like either may or may not be present in the
alkylene group), in one embodiment with at least 1 carbon atom, and
in one embodiment with no more than about 54 carbon atoms, and in
another embodiment with no more than about 36 carbon atoms,
although the number of carbon atoms can be outside of these ranges,
[0095] (ii) arylene groups (wherein an arylene group is defined as
a divalent aromatic group or aryl group, including substituted and
unsubstituted arylene groups, and wherein heteroatoms, such as
oxygen, nitrogen, sulfur, silicon, phosphorus, boron, and the like
either may or may not be present in the arylene group), in one
embodiment with at least about 5 carbon atoms, and in another
embodiment with at least about 6 carbon atoms, and in one
embodiment with no more than about 14 carbon atoms, in another
embodiment with no more than about 10 carbon atoms, and in yet
another embodiment with no more than about 7 carbon atoms, although
the number of carbon atoms can be outside of these ranges, [0096]
(iii) arylalkylene groups (wherein an arylalkylene group is defined
as a divalent arylalkyl group, including substituted and
unsubstituted arylalkylene groups, wherein the alkyl portion of the
arylalkylene group can be linear or branched, saturated or
unsaturated, and cyclic or acyclic, and wherein heteroatoms, such
as oxygen, nitrogen, sulfur, silicon, phosphorus, boron, and the
like either may or may not be present in either the aryl or the
alkyl portion of the arylalkylene group), in one embodiment with at
least about 6 carbon atoms, and in another embodiment with at least
about 7 carbon atoms, and in one embodiment with no more than about
32 carbon atoms, in another embodiment with no more than about 22
carbon atoms, and in yet another embodiment with no more than about
8 carbon atoms, although the number of carbon atoms can be outside
of these ranges, or [0097] (iv) alkylarylene groups (wherein an
alkylarylene group is defined as a divalent alkylaryl group,
including substituted and unsubstituted alkylarylene groups,
wherein the alkyl portion of the alkylarylene group can be linear
or branched, saturated or unsaturated, and cyclic or acyclic, and
wherein heteroatoms, such as oxygen, nitrogen, sulfur, silicon,
phosphorus, boron, and the like either may or may not be present in
either the aryl or the alkyl portion of the alkylarylene group), in
one embodiment with at least about 6 carbon atoms, and in another
embodiment with at least about 7 carbon atoms, and in one
embodiment with no more than about 32 carbon atoms, in another
embodiment with no more than about 22 carbon atoms, and in yet
another embodiment with no more than about 7 carbon atoms, although
the number of carbon atoms can be outside of these ranges, wherein
the substituents on the substituted alkylene, arylene,
arylalkylene, and alkylarylene groups can be (but are not limited
to) halogen atoms, cyano groups, ether groups, aldehyde groups,
ketone groups, ester groups, amide groups, carbonyl groups,
thiocarbonyl groups, phosphine groups, phosphonium groups,
phosphate groups, nitrile groups, mercapto groups, nitro groups,
nitroso groups, acyl groups, acid anhydride groups, azide groups,
azo groups, cyanato groups, urethane groups, urea groups, mixtures
thereof, and the like, wherein two or more substituents can be
joined together to form a ring;
[0098] R.sub.3 and R.sub.3' each, independently of the other, are
either: [0099] (a) photoinitiating groups, such as groups derived
from 14442-hydroxyethoxy)phenyl)-2-hydroxy-2-methylpropan-1-one, of
the formula
##STR00025##
[0099] groups derived from 1-hydroxycyclohexylphenylketone, of the
formula
##STR00026##
groups derived from 2-hydroxy-2-methyl-1-phenylpropan-1-one, of the
formula
##STR00027##
groups derived from N,N-dimethylethanolamine or
N,N-dimethylethylenediamine, of the formula
##STR00028##
[0100] or the like, or: [0101] (b) a group which is: [0102] (i) an
alkyl group (including linear and branched, saturated and
unsaturated, cyclic and acyclic, and substituted and unsubstituted
alkyl groups, and wherein heteroatoms, such as oxygen, nitrogen,
sulfur, silicon, phosphorus, boron, and the like either may or may
not be present in the alkyl group), in one embodiment with at least
about 2 carbon atoms, in another embodiment with at least about 3
carbon atoms, and in yet another embodiment with at least about 4
carbon atoms, and in one embodiment with no more than about 100
carbon atoms, in another embodiment with no more than about 60
carbon atoms, and in yet another embodiment with no more than about
30 carbon atoms, although the number of carbon atoms can be outside
of these ranges, [0103] (ii) an aryl group (including substituted
and unsubstituted aryl groups, and wherein heteroatoms, such as
oxygen, nitrogen, sulfur, silicon, phosphorus, boron, and the like
either may or may not be present in the aryl group), in one
embodiment with at least about 5 carbon atoms, and in another
embodiment with at least about 6 carbon atoms, and in one
embodiment with no more than about 100 carbon atoms, in another
embodiment with no more than about 60 carbon atoms, and in yet
another embodiment with no more than about 30 carbon atoms,
although the number of carbon atoms can be outside of these ranges,
such as phenyl or the like, [0104] (iii) an arylalkyl group
(including substituted and unsubstituted arylalkyl groups, wherein
the alkyl portion of the arylalkyl group can be linear or branched,
saturated or unsaturated, and cyclic or acyclic, and wherein
heteroatoms, such as oxygen, nitrogen, sulfur, silicon, phosphorus,
boron, and the like either may or may not be present in either the
aryl or the alkyl portion of the arylalkyl group), in one
embodiment with at least about 6 carbon atoms, and in another
embodiment with at least about 7 carbon atoms, and in one
embodiment with no more than about 100 carbon atoms, in another
embodiment with no more than about 60 carbon atoms, and in yet
another embodiment with no more than about 30 carbon atoms,
although the number of carbon atoms can be outside of these ranges,
such as benzyl or the like, or [0105] (iv) an alkylaryl group
(including substituted and unsubstituted alkylaryl groups, wherein
the alkyl portion of the alkylaryl group can be linear or branched,
saturated or unsaturated, and cyclic or acyclic, and wherein
heteroatoms, such as oxygen, nitrogen, sulfur, silicon, phosphorus,
boron, and the like either may or may not be present in either the
aryl or the alkyl portion of the alkylaryl group), in one
embodiment with at least about 6 carbon atoms, and in another
embodiment with at least about 7 carbon atoms, and in one
embodiment with no more than about 100 carbon atoms, in another
embodiment with no more than about 60 carbon atoms, and in yet
another embodiment with no more than about 30 carbon atoms,
although the number of carbon atoms can be outside of these ranges,
such as tolyl or the like, wherein the substituents on the
substituted alkyl, arylalkyl, and alkylaryl groups can be (but are
not limited to) halogen atoms, ether groups, aldehyde groups,
ketone groups, ester groups, amide groups, carbonyl groups,
thiocarbonyl groups, sulfide groups, phosphine groups, phosphonium
groups, phosphate groups, nitrite groups, mercapto groups, nitro
groups, nitroso groups, acyl groups, acid anhydride groups, azide
groups, azo groups, cyanato groups, isocyanato groups, thiocyanato
groups, isothiocyanato groups, carboxylate groups, carboxylic acid
groups, urethane groups, urea groups, mixtures thereof, and the
like, wherein two or more substituents can be joined together to
form a ring; [0106] and X and X' each, independently of the other,
is an oxygen atom or a group of the formula --NR.sub.4--, wherein
R.sub.4 is: [0107] (i) a hydrogen atom; [0108] (ii) an alkyl group,
including linear and branched, saturated and unsaturated, cyclic
and acyclic, and substituted and unsubstituted alkyl groups, and
wherein heteroatoms either may or may not be present in the alkyl
group, in one embodiment with at least 1 carbon atom, and in one
embodiment with no more than about 100 carbon atoms, in another
embodiment with no more than about 60 carbon atoms, and in yet
another embodiment with no more than about 30 carbon atoms,
although the number of carbon atoms can be outside of these ranges,
[0109] (iii) an aryl group, including substituted and unsubstituted
aryl groups, and wherein heteroatoms either may or may not be
present in the aryl group, in one embodiment with at least about 5
carbon atoms, and in another embodiment with at least about 6
carbon atoms, and in one embodiment with no more than about 100
carbon atoms, in another embodiment with no more than about 60
carbon atoms, and in yet another embodiment with no more than about
30 carbon atoms, although the number of carbon atoms can be outside
of these ranges, [0110] (iv) an arylalkyl group, including
substituted and unsubstituted arylalkyl groups, wherein the alkyl
portion of the arylalkyl group can be linear or branched, saturated
or unsaturated, and cyclic or acyclic, and wherein heteroatoms
either may or may not be present in either the aryl or the alkyl
portion of the arylalkyl group, in one embodiment with at least
about 6 carbon atoms, and in another embodiment with at least about
7 carbon atoms, and in one embodiment with no more than about 100
carbon atoms, in another embodiment with no more than about 60
carbon atoms, and in yet another embodiment with no more than about
30 carbon atoms, although the number of carbon atoms can be outside
of these ranges, or [0111] (v) an alkylaryl group, including
substituted and unsubstituted alkylaryl groups, wherein the alkyl
portion of the alkylaryl group can be linear or branched, saturated
or unsaturated, and cyclic or acyclic, and wherein heteroatoms
either may or may not be present in either the aryl or the alkyl
portion of the alkylaryl group, in one embodiment with at least
about 6 carbon atoms, and in another embodiment with at least about
7 carbon atoms, and in one embodiment with no more than about 100
carbon atoms, in another embodiment with no more than about 60
carbon atoms, and in yet another embodiment with no more than about
30 carbon atoms, although the number of carbon atoms can be outside
of these ranges, wherein the substituents on the substituted alkyl,
aryl, arylalkyl, and alkylaryl groups can be (but are not limited
to) halogen atoms, ether groups, aldehyde groups, ketone groups,
ester groups, amide groups, carbonyl groups, thiocarbonyl groups,
sulfate groups, sulfonate groups, sulfonic acid groups, sulfide
groups, sulfoxide groups, phosphine groups, phosphonium groups,
phosphate groups, nitrile groups, mercapto groups, nitro groups,
nitroso groups, sulfone groups, acyl groups, acid anhydride groups,
azide groups, azo groups, cyanato groups, isocyanato groups,
thiocyanato groups, isothiocyanato groups, carboxylate groups,
carboxylic acid groups, urethane groups, urea groups, mixtures
thereof, and the like, wherein two or more substituents can be
joined together to form a ring.
[0112] In one specific embodiment, R.sub.2 and R.sub.2' are the
same as each other; in another specific embodiment, R.sub.2 and
R.sub.2' are different from each other. In one specific embodiment,
R.sub.3 and R.sub.3' are the same as each other; in another
specific embodiment, R.sub.3 and R.sub.3' are different from each
other.
[0113] In one specific embodiment, R.sub.2 and R.sub.2' are each
groups of the formula --C.sub.34H.sub.56+a-- and are branched
alkylene groups which may include unsaturations and cyclic groups,
wherein a is an integer of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or
12, including (but not limited to) isomers of the formula
##STR00029##
[0114] In one specific embodiment, R.sub.1 is an ethylene
(--CH.sub.2CH.sub.2--) group.
[0115] In one specific embodiment, R.sub.3 and R.sub.3' are
both
##STR00030##
[0116] In one specific embodiment, the compound is of the
formula
##STR00031##
wherein --C.sub.34H.sub.56+a-- represents a branched alkylene group
which may include unsaturations and cyclic groups, wherein a is an
integer of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12, including
(but not limited to) isomers of the formula
##STR00032##
[0117] Additional specific examples of compounds of this formula
include those of the formula
##STR00033##
wherein --C.sub.34H.sub.56+a-- represents a branched alkylene group
which may include unsaturations and cyclic groups, wherein a is an
integer of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 and wherein
m is an integer, including but not limited to embodiments wherein m
is 2, including (but not limited to) isomers of the formula
##STR00034##
those of the formula
##STR00035##
wherein --C.sub.34H.sub.56+a-- represents a branched alkylene group
which may include unsaturations and cyclic groups, wherein a is an
integer of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 and wherein
n is an integer, including but not limited to embodiments wherein n
is 2 and wherein n is 5, including (but not limited to) isomers of
the formula
##STR00036##
those of the formula
##STR00037##
wherein --C.sub.34H.sub.56+a-- represents a branched alkylene group
which may include unsaturations and cyclic groups, wherein a is an
integer of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 and wherein
p is an integer, including but not limited to embodiments wherein p
is 2 and wherein p is 3, including (but not limited to) isomers of
the formula
##STR00038##
those of the formula
##STR00039##
wherein --C.sub.34H.sub.56+a-- represents a branched alkylene group
which may include unsaturations and cyclic groups, wherein a is an
integer of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 and wherein
q is an integer, including but not limited to embodiments wherein q
is 2 and wherein q is 3, including (but not limited to) isomers of
the formula
##STR00040##
those of the formula
##STR00041##
wherein --C.sub.34H.sub.56+a-- represents a branched alkylene group
which may include unsaturations and cyclic groups, wherein a is an
integer of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 and wherein
r is an integer, including but not limited to embodiments wherein r
is 2 and wherein r is 3, including (but not limited to) isomers of
the formula
##STR00042##
and the like, as well as mixtures thereof.
[0118] Compounds as disclosed herein can be prepared by any desired
or effective method. For example, in one specific embodiment, about
two molar equivalents of a diacid of the formula
HOOC--R.sub.2--COOH
about one molar equivalent of a diamine of the formula
H.sub.2N--R.sub.1--NH.sub.2
and about two molar equivalents of a monoalcohol of the formula
R.sub.3--OH
can be reacted by use of the coupling agent such as
1,3-dicyclohexylcarbodiimide (DCC) in the presence of a catalyst
such as 4-dimethylaminopyridine (DMAP), in the presence of an
optional solvent such as methylene chloride (CH2C12). The
ingredients can be mixed together and a one-pot reaction can be
employed. More specifically, the diacid, the diamine, and the
dicyclohexylcarbodiimide can be mixed together in a first step, and
the monoalcohol can be added to the reaction mixture in a second
step. The reaction proceeds as follows:
##STR00043##
wherein A is the coupling agent.
[0119] The diacid and the diamine are present in any desired or
effective relative amounts, in one embodiment at least about 0.4
mole of diamine per every 1 mole of diacid, in another embodiment
at least about 0.45 mole of diamine per every 1 mole of diacid, and
in yet another embodiment at least about 0.5 mole of diamine per
every one mole of diacid, and in one embodiment no more than about
0.57 mole of diamine per every 1 mole of diacid, in another
embodiment no more than about 0.53 mole of diamine per every 1 mole
of diacid, and in yet another embodiment no more than about 0.51
mole of diamine per every 1 mole of diacid, although the relative
amounts can be outside of these ranges.
[0120] The diacid and the monoalcohol are present in any desired or
effective relative amounts, in one embodiment at least about 0.75
mole of monoalcohol per every 1 mole of diacid, in another
embodiment at least about 0.9 mole of monoalcohol per every 1 mole
of diacid, and in yet another embodiment at least about 1 mole of
monoalcohol per every one mole of diacid, and in one embodiment no
more than about 1.5 moles of monoalcohol per every 1 mole of
diacid, in another embodiment no more than about 1.4 moles of
monoalcohol per every 1 mole of diacid, and in yet another
embodiment no more than about 1.25 moles of monoalcohol per every 1
mole of diacid, although the relative amounts can be outside of
these ranges.
[0121] The diamine and the monoalcohol are present in any desired
or effective relative amounts, in one embodiment at least about 1.5
moles of monoalcohol per every 1 mole of diamine, in another
embodiment at least about 1.75 moles of monoalcohol per every 1
mole of diamine, and in yet another embodiment at least about 2
moles of monoalcohol per every one mole of diamine, and in one
embodiment no more than about 2.5 moles of monoalcohol per every 1
mole of diamine, in another embodiment no more than about 2.4 moles
of monoalcohol per every 1 mole of diamine, and in yet another
embodiment no more than about 2.25 moles of monoalcohol per every 1
mole of diamine, although the relative amounts can be outside of
these ranges.
[0122] Examples of suitable coupling agents include
1,3-dicyclohexylcarbodiimide (DCC), of the formula
##STR00044##
1[3-(dimethylamino)propyl]3-ethylcarbodiimide HCl (EDCl),
N,N-carbonyldiimidazole,
N-cyclohexyl-N'-(2-morpholinoethyl)-carbodiimide
methyl-p-toluenesulfonate,
(benzotriazol-1-yloxy)tris(dimethylamino)phosphonium
hexafluorophosphate (BOP),
(o-benzotriazol-1-yl)-N,N,N',N'-bis(tetramethylene)uronium
hexafluorophosphate (HBTU), bis(2-oxo-3-oxazolidinyl)phosphonic
chloride (BOP--Cl),
(1H-1,2,3-benzotriazol-1-yloxy)tris(pyrrolidino)phosphonium
hexafluorophosphate (PyBOP), and the like, as well as mixtures
thereof
[0123] The coupling agent and the diacid are present in any desired
or effective relative amounts, in one embodiment at least about 0.4
mole of diacid per every 1 mole of coupling agent, in another
embodiment at least about 0.45 mole of diacid per every 1 mole of
coupling agent, and in yet another embodiment at least about 0.5
mole of diacid per every one mole of coupling agent, and in one
embodiment no more than about 0.57 mole of diacid per every 1 mole
of coupling agent, in another embodiment no more than about 0.53
mole of diacid per every 1 mole of coupling agent, and in yet
another embodiment no more than about 0.51 mole of diacid per every
1 mole of coupling agent, although the relative amounts can be
outside of these ranges.
[0124] Examples of suitable catalysts include
4-dimethylaminopyridine (DMAP), of the formula
##STR00045##
triethylamine, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), and the
like, as well as mixtures thereof.
[0125] The catalyst and the diacid are present in any desired or
effective relative amounts, in one embodiment at least about 0.05
mole of catalyst per every 1 mole of diacid, in another embodiment
at least about 0.1 mole of catalyst per every 1 mole of diacid, and
in yet another embodiment at least about 0.2 mole of catalyst per
every one mole of diacid, and in one embodiment no more than about
1 mole of catalyst per every 1 mole of diacid, in another
embodiment no more than about 0.8 mole of catalyst per every 1 mole
of diacid, and in yet another embodiment no more than about 0.5
mole of catalyst per every 1 mole of diacid, although the relative
amounts can be outside of these ranges.
[0126] When the optional solvent is employed, any desired or
effective solvent can be employed. Examples of suitable solvents
include methylene chloride, tetrahydrofuran, methyl ethyl ketone,
toluene, dimethyl formamide, diethyl ether, hexane, ethyl acetate,
and the like, as well as mixtures thereof.
[0127] When the optional solvent is employed, the solvent can be
present in any desired or effective amount, in one embodiment at
least about 30 grams of diacid per liter of solvent, in another
embodiment at least about 40 grams of diacid per liter of solvent,
and in yet another embodiment at least about 50 grams of diacid per
liter of solvent, and in one embodiment no more than about 150
grams of diacid per liter of solvent, in another embodiment no more
than about 125 grams of diacid per liter of solvent, and in yet
another embodiment no more than about 100 grams of diacid per liter
of solvent, although the amount of solvent can be outside of these
ranges.
[0128] The reaction between the diacid and the diamine in the first
step of the reaction can be carried out at any desired or effective
temperature, in one embodiment at least about -5.degree. C., in
another embodiment at least about -2.5.degree. C., and in yet
another embodiment at least about 0.degree. C., and one embodiment
no more than about 5.degree. C., in another embodiment no more than
about 3.degree. C., and in yet another embodiment no more than
about 2.degree. C., although the temperature can be outside of
these ranges. Thereafter, the reaction product of the diacid and
diamine can be reacted with the monoalcohol at any desired or
effective temperature, in one embodiment at least about 15.degree.
C., in another embodiment at least about 20.degree. C., and in yet
another embodiment at least about 25.degree. C., and one embodiment
no more than about 35.degree. C., in another embodiment no more
than about 30.degree. C., and in yet another embodiment no more
than about 27.degree. C., although the temperature can be outside
of these ranges.
[0129] The reaction between the diacid, the diamine, and the
monoalcohol can be carried out for any desired or effective period
of time, in one embodiment at least about 3.5 hours, in another
embodiment at least about 4 hours, and in yet another embodiment at
least about 4.5 hours, and in one embodiment no more than about 6.5
hours, in another embodiment no more than about 6 hours, and in
another embodiment no more than about 5 hours, although the period
of time can be outside of these ranges.
[0130] Subsequent to completion of the reaction, the product can be
isolated by filtration of any solid by-products, or by washing the
solution with water depending on the activating agent used. The
solvent can be removed by rotary evaporation. If needed, the
product can be purified by washing with acetone and drying.
[0131] Compounds as disclosed herein can also be prepared by first
reacting about two molar equivalents of a diacid of the formula
HOOC--R.sub.2--COOH
and about one molar equivalent of a diamine of the formula
H.sub.2 N--R.sub.1--NH.sub.2
under neat conditions (i.e., in the absence of a solvent) at
elevated temperatures while removing water from the reaction
mixture to form an acid-terminated oligoamide of the formula
##STR00046##
[0132] Thereafter, the acid-terminated oligoamide thus formed can
be reacted with about 2 molar equivalents of a monoalcohol of the
formula R.sub.3--OH by use of a coupling agent such as
1,3-dicyclohexylcarbodiimide (DCC) in the presence of a catalyst
such as 4-dimethylaminopyridine (DMAP) in the presence of a solvent
such as methylene chloride (CH.sub.2Cl.sub.2) at reduced
temperatures. The reaction proceeds as follows:
##STR00047##
[0133] The diacid and the diamine are present in any desired or
effective relative amounts, in one embodiment at least about 0.75
mole of diamine per every 2 moles of diacid, in another embodiment
at least about 0.85 mole of diamine per every 2 moles of diacid,
and in yet another embodiment at least about 1 mole of diamine per
every 2 moles of diacid, and in one embodiment no more than about
1.5 moles of diamine per every 2 moles of diacid, in another
embodiment no more than about 1.35 moles of diamine per every 2
moles of diacid, and in yet another embodiment no more than about
1.25 moles of diamine per every 2 moles of diacid, although the
relative amounts can be outside of these ranges.
[0134] Water can be removed from the reaction mixture between the
diacid and the diamine by any desired or effective method, such as
by a Dean-Stark trap, molecular sieves or other drying agents, or
the like.
[0135] The reaction between the diacid and the diamine generally is
run neat, i.e., in the absence of a solvent, although a solvent can
be used if desired.
[0136] The reaction between the diacid and the diamine can be
carried out at any desired or effective temperature, in one
embodiment at least about 130.degree. C., in another embodiment at
least about 140.degree. C., and in yet another embodiment at least
about 155.degree. C., and one embodiment no more than about
180.degree. C., in another embodiment no more than about
175.degree. C., and in yet another embodiment no more than about
165.degree. C., although the temperature can be outside of these
ranges.
[0137] The reaction between the diacid and the diamine can be
carried out for any desired or effective period of time, in one
embodiment at least about 2 hours, in another embodiment at least
about 2.5 hours, and in yet another embodiment at least about 3
hours, and in one embodiment no more than about 5 hours, in another
embodiment no more than about 4.5 hours, and in another embodiment
no more than about 4 hours, although the period of time can be
outside of these ranges.
[0138] Thereafter, the acid-terminated oligoamide intermediate and
the monoalcohol are reacted in the presence of a coupling agent, a
catalyst, and a solvent.
[0139] Examples of suitable coupling agents include
1,3-dicyclohexylcarbodiimide (DCC), of the formula
##STR00048##
1-[3-(dimethylamino)propyl]3-ethylcarbodiimide HCl (EDCl),
N,N-carbonyldiimidazole,
N-cyclohexyl-N'-(2-morphohnoethyl)-carbodiimide
methyl-p-toluenesulfonate,
(benzotriazol-1-yloxy)tris(dimethylamino)phosphonium
hexafluorophosphate (BOP),
(o-benzotriazol-1-yl)-N,N,N',N'-bis(tetramethylene)uronium
hexafluorophosphate (HBTU), bis(2-oxo-3-oxazolidinyl)phosphonic
chloride (BOP--Cl),
(1H-1,2,3-benzotriazol-1-yloxy)tris(pyrrolidino)phosphonium
hexafluorophosphate (PyBOP), and the like, as well as mixtures
thereof.
[0140] Examples of suitable catalysts include
4-dimethylaminopyridine (DMAP), of the formula
##STR00049##
triethylamine, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), and the
like, as well as mixtures thereof.
[0141] The acid-terminated oligoamide intermediate and the
monoalcohol are present in any desired or effective relative
amounts, in one embodiment at least about 2 moles of monoalcohol
per every 1 mole of acid-terminated oligoamide intermediate, in
another embodiment at least about 2.15 moles of monoalcohol per
every 1 mole of acid-terminated oligoamide intermediate, and in yet
another embodiment at least about 2.25 moles of monoalcohol per
every one mole of acid-terminated oligoamide intermediate, and in
one embodiment no more than about 2.75 moles of monoalcohol per
every 1 mole of acid-terminated oligoamide intermediate, in another
embodiment no more than about 2.5 moles of monoalcohol per every 1
mole of acid-terminated oligoamide intermediate, and in yet another
embodiment no more than about 2.4 moles of monoalcohol per every 1
mole of acid-terminated oligoamide intermediate, although the
relative amounts can be outside of these ranges.
[0142] The acid-terminated oligoamide and the coupling agent are
present in any desired or effective relative amounts, in one
embodiment at least about 1.8 moles of coupling agent per every 1
mole of diacid diamide, in another embodiment at least about 2
moles of coupling agent per every 1 mole of diacid diamide, and in
yet another embodiment at least about 2.2 moles of coupling agent
per every one mole of diacid diamide, and in one embodiment no more
than about 3 moles of coupling agent per every 1 mole of diacid
diamide, in another embodiment no more than about 2.8 moles of
coupling agent per every 1 mole of diacid diamide, and in yet
another embodiment no more than about 2.5 moles of coupling agent
per every 1 mole of diacid diamide, although the relative amounts
can be outside of these ranges.
[0143] The catalyst and the acid-terminated oligoamide intermediate
are present in any desired or effective relative amounts, in one
embodiment at least about 0.05 mole of catalyst per every 1 mole of
acid-terminated oligoamide intermediate, in another embodiment at
least about 0.1 moles of catalyst per every 1 mole of
acid-terminated oligoamide intermediate, and in yet another
embodiment at least about 0.2 mole of catalyst per every one mole
of acid-terminated oligoamide intermediate, and in one embodiment
no more than about 1 mole of catalyst per every 1 mole of
acid-terminated oligoamide intermediate, in another embodiment no
more than about 0.8 mole of catalyst per every 1 mole of
acid-terminated oligoamide intermediate, and in yet another
embodiment no more than about 0.5 mole of catalyst per every 1 mole
of acid-terminated oligoamide intermediate, although the relative
amounts can be outside of these ranges.
[0144] Any desired or effective solvent can be employed. Examples
of suitable solvents include methylene chloride, tetrahydrofuran,
methyl ethyl ketone, toluene, dimethyl formamide, diethyl ether,
hexane, ethyl acetate, and the like, as well as mixtures
thereof.
[0145] The solvent can be present in any desired or effective
amount, in one embodiment at least about 20 milliliters of solvent
per gram of acid-terminated oligoamide intermediate, in another
embodiment at least about 25 milliliters of solvent per gram of
acid-terminated oligoamide intermediate, and in yet another
embodiment at least about 30 milliliters of solvent per gram of
acid-terminated oligoamide intermediate, and in one embodiment no
more than about 100 milliliters of solvent per gram of
acid-terminated oligoamide intermediate, in another embodiment no
more than about 90 milliliters of solvent per gram of
acid-terminated oligoamide intermediate, and in yet another
embodiment no more than about 80 milliliters of solvent per gram of
acid-terminated oligoamide intermediate, although the amount of
solvent can be outside of these ranges.
[0146] The reaction between the acid-terminated oligoamide
intermediate, the monoalcohol, and the coupling agent can be
carried out at any desired or effective temperature, in one
embodiment at least about 15.degree. C., in another embodiment at
least about 20.degree. C., and in yet another embodiment at least
about 25.degree. C., and one embodiment no more than about
40.degree. C., in another embodiment no more than about 35.degree.
C., and in yet another embodiment no more than about 30.degree. C.,
although the temperature can be outside of these ranges.
[0147] The reaction between the acid-terminated oligoamide
intermediate, the monoalcohol, and the coupling agent can be
carried out for any desired or effective period of time, in one
embodiment at least about 2 hours, in another embodiment at least
about 2.5 hours, and in yet another embodiment at least about 3
hours, and in one embodiment no more than about 5 hours, in another
embodiment no more than about 4.5 hours, and in another embodiment
no more than about 4 hours, although the period of time can be
outside of these ranges.
[0148] Subsequent to completion of the reaction, the product can be
recovered by any desired or effective method, such as filtration of
any solid by-products or washing the solution with water depending
on the coupling agent used. The solvent can be removed by rotary
evaporation. If needed, the product can be purified by washing with
acetone and dried in a vacuum oven.
[0149] Analogous procedures can be employed using amine compounds
of the formula HNR.sub.3R.sub.4 in place of monoalcohols of the
formula R.sub.3OH.
[0150] In a further embodiment, one of the one or more gellants in
the ink vehicle is a composite material comprised of a
polymerizable epoxy resin that is chemically functionalized with
either ethylenically unsaturated groups or hydrocarbon groups or
combinations thereof, and a polyamide resin based on a polymerized
fatty acid and a polyamine, and an optional reactive diluent that
optionally contains unsaturated functional groups.
[0151] The gellant composition comprised of epoxy resin and
polyamide resin exhibits a thermally reversible and narrow gel
phase transition when formulated into a phase change radiation
curable ink composition. For example, at a temperature of
30.degree. C. suitable for transfuse printing, the radiation
curable gel ink exhibits gel state viscosities of at least 10.sup.4
mPas. Further, at temperatures of from about 30.degree. C. to about
50.degree. C., the ink in one embodiment has a storage modulus of
at least 10.sup.2 Pa. Such viscoelastic rheology is useful for
transfuse printing onto an intermediate transfer surface, since the
gelled ink droplets are able to transfer the ink from the
intermediate transfer surface to an image receiving substrate such
as paper. Further, the ink does not typically experience any
obvious phase-separation (separating into its liquid and solid
material components) during the transfuse process by the action of
the pressure roll.
[0152] The epoxy resin component in the composite gellant can be
any suitable epoxy group-containing material. In specific
embodiments, the epoxy resin component is selected from among the
diglycidyl ethers of either polyphenol-based epoxy resin or a
polyol-based epoxy resin, or mixtures thereof. These epoxy resins
have two epoxy functional groups that are preferably located at the
terminal ends of the molecule. The polyphenol-based epoxy resin is
preferably a bisphenol A-co-epichlorohydrin resin with not more
than two glycidyl ether terminal groups. The polyol-based epoxy
resin in these embodiments is a dipropylene
glycol-co-epichlorohydrin resin with not more than two glycidyl
ether terminal groups. Epoxy resins have a weight average molecular
weight in the range of in one embodiment about 200 to about 800,
and in another embodiment of about 300 to about 700, although the
molecular weight can be outside of these ranges. Commercially
available sources of epoxy resins are, for example, the bisphenol-A
based epoxy resins from Dow Chemical Corp. such as DER 383, or the
dipropyleneglycol-based resins from Dow Chemical Corp. such as DER
736. Other sources of epoxy-based materials originating from
natural sources may be used, such as epoxidized triglyceride fatty
esters of vegetable or animal origins, for example epoxidized
linseed oil, rapeseed oil and the like, or mixtures thereof. Epoxy
compounds derived from vegetable oils such as the VIKOFLEX line of
products from Arkema Inc., Philadelphia Pa. may also be used.
[0153] Further, the epoxy resin component contains at least one
ethylenically unsaturated functional group that is curable via
free-radical initiation and enables chemical bonding of the gellant
to the cured ink vehicle. The epoxy resin component is thus
functionalized with acrylate or (meth)acrylate, vinyl ether, allyl
ether and the like, by chemical reaction with unsaturated
carboxylic acids or other unsaturated reagents. For example, the
terminal epoxide groups of the resin become ring-opened in this
chemical reaction, and are converted to (meth)acrylate esters by
esterification reaction with (meth)acrylic acid.
[0154] Furthermore, the epoxy resin component may additionally be
functionalized by reaction with a saturated hydrocarbon
monocarboxylic acid comprised of in one embodiment at least 8
carbons, and in another embodiment at least 10 carbons, such as
capric acid, lauric acid, myristic acid, stearic acid and
12-hydroxystearic acid, and the like. The saturated monocarboxylic
acid is in one specific embodiment a linear, non-branched
hydrocarbon acid, rather than a branched hydrocarbon acid, the
latter which can in some instances act to physically disrupt the
gellant network structure. The weight-percent ratio of the
unsaturated monocarboxylic acid to linear saturated monocarboxylic
acid that is used to chemically functionalize the epoxy resin
component can range from about 1:1 to about 20:1, and is in other
embodiments from about 2:1 to about 5:1, but can also be outside of
these ranges. The condensation reaction between the terminal
epoxide functional groups on the epoxy resin and the unsaturated or
saturated carboxylic acids can, if desired, be accelerated by use
of a suitable catalyst, for example triphenyl phosphine, bulky
tertiary bases such as DABCO, triisopropylamine, alkoxylate salts
such as potassium tert-butoxide, and the like. The amount of
catalyst used is in one embodiment less than about 5 wt %, and in
another embodiment less than about 1 wt % of total solid
components.
[0155] As the polyamide component of the epoxy-polyamide composite
gellant, any suitable polyamide material may be used without
limitation. Preferably, the polyamide is comprised of a polyamide
resin derived from a polymerized fatty acid such as those obtained
from natural sources (for example, palm oil, rapeseed oil, castor
oil, and the like, including mixtures thereof) or the commonly
known hydrocarbon "dimer acid," prepared from dimerized C-18
unsaturated acid feedstocks such as oleic acid, linoleic acid and
the like, and a polyamine, most preferably a diamine (for example,
alkylenediamines such as ethylenediamine, DYTEK.RTM. series
diamines, poly(alkyleneoxy)diamines, and the like, or also
copolymers of polyamides such as polyester-polyamides and
polyether-polyamides. One or more polyamide resins may be used in
the formation of the curable gellant. Commercially available
sources of the polyamide resin include, for example, the VERSAMID
series of polyamides available from Cognis Corporation (formerly
Henkel Corp.), in particular VERSAMID 335, VERSAMID 338, VERSAMID
795 and VERSAMID 963, all of which have low molecular weights and
low amine numbers. The SYLVAGEL.RTM. polyamide resins from Arizona
Chemical Company, and variants thereof including
polyether-polyamide resins may be employed. The composition of the
SYLVAGEL.RTM. resins obtained from Arizona Chemical Company are
disclosed in U.S. Pat. Nos. 6,492,458 and 6,399,713 and U.S. Patent
Publication No. US 2003/0065084, which are totally incorporated
herein by reference, and are described as polyalkyleneoxydiamine
polyamides with the general formula,
##STR00050##
wherein R.sub.1 is an alkyl group having at least seventeen
carbons, R.sub.2 includes a polyalkyleneoxide, R.sub.3 includes a
C-6 carbocyclic group, and n is an integer of at least 1.
[0156] The polyamide resin is in one embodiment of low molecular
weight, with number average molecular weight of less than about
15,000 grams per mole, in another embodiment less than about 10,000
grams per mole, and in yet another embodiment less than about 7,000
grams per mole, as determined by gel permeation chromatography
(GPC) referenced with a polystyrene standard. The amine number of
the polyamide resin is typically low, with values in the range of
in one embodiment from 0 to about 10, and in another embodiment
with values in the range of from 0 to about 5.
[0157] The curable epoxy polyamide composite gellants can be
prepared by any suitable method, such as by mixing the epoxy resin
components with the ethylenically unsaturated group-containing
component and optional saturated hydrocarbon monocarboxylic acid,
in the presence of the polyamide resin and an esterification
catalyst, and then heating the mixture over several hours while
stirring sufficiently to blend all of the components so as to
obtain a homogeneous mixture. The reaction is allowed to progress
for a suitable time period, whereby conversion to the desired
products is monitored spectroscopically and by the change in total
acid number.
[0158] The relative weight-percent ratio of epoxy resin components
and polyamide resin components in the gellant composition may range
from, for example, 20:1 to 0.1:1, but can also be outside of these
ranges. The impact of this ratio upon ink performance is
multi-faceted. While the structures of the epoxy resin and
polyamide resin components can vary, in general the epoxy resin
component provides more solubility in common reactive diluents
while the less soluble, more polar polyamide component provides
greater gel properties. The epoxy resin component is more readily
reacted with acrylic acid to provide acrylate functionality than
the polyamide resin, and thus imparts higher levels of cure to the
final image.
[0159] An illustration of the effect of the ratio of epoxy resin to
polyamide resin with a particular selection of the respective
resins upon the storage modulus G.degree. of the ink may be seen
from the fact that at a ratio of 1.3:1.0, the storage modulus of
the ink is 7.times.10.sup.3 Pa and the ratio of jetting viscosity
to gel viscosity at 30.degree. C. is 1.5.times.10.sup.5, while at a
ratio of 0.5:1.0, the storage modulus is 3.4.times.10.sup.2 Pa and
the ratio of jetting viscosity to gel viscosity at 30.degree. C. is
9.4.times.10.sup.3.
[0160] The results indicate that two gellants with different
relative ratios of the very same epoxy resin and polyamide resin
components can exert a dramatically different effect on the
viscoelastic behavior of the ink composition.
[0161] While not being limited to any particular theory, the
polyamide resin is believed to function as the principal gelling
agent in the composite gellant, since polyamides, and amide groups
in general, are known to form extensive hydrogen-bonded networks in
the presence of other solvents or components that are proton
sources, including alcohols, phenols, amines and carboxylic
acids.
[0162] The radiation curable phase change ink compositions are
comprised of the curable epoxy-polyamide composite gellant in an
amount in one embodiment from about 1% to about 50% by weight of
the ink, in another embodiment from about 5% to about 25% by weight
of the ink, and in yet another embodiment from about 7% to about
15% by weight of the ink, although the value can also be outside of
this range.
[0163] In the composition of the curable epoxy-polyamide composite
gellant is also optionally included a reactive diluent. Such
diluents may include one or more monomers, one or more oligomers,
one or more polymers, or any mixture/combination thereof The
reactive diluent can function as a solvent to dilute the gellant
composition and enable the appropriate rheological properties, such
as gellant viscosity and elasticity, but does not participate in
any way with the chemical functionalization of the epoxy resin
component. Furthermore, the optional reactive diluent becomes a
part of the liquid components integrated within the gellant network
structure, such that upon curing of an ink that is comprised of the
same reactive diluent, the composite gellant material will be
covalently linked with the cured ink vehicle and will thereby
resist phase separation during the printing process. Examples of
reactive diluents that are suitable for the gellant composition
include monomers such as (meth)acrylate esters such as
isobornyl(meth)acrylate and lauryl(meth)acrylate, vinyl ethers or
vinyl esters, allylic esters or allylic ethers, vinyl or allyl
arenes such as styrene and vinyl toluene, and the like.
Commercially available sources of reactive diluents that are also
used within the ink vehicle composition include, for example,
propoxylated neopentyl glycol diacrylate (available from Sartomer
Co. Inc. as SR9003), and glycerol propoxylate triacrylate, and the
like.
[0164] For example, where the organic gellant is cationically
curable (e.g., wherein the curable functional groups include epoxy,
vinyl ether, allyl, styrene and other vinyl benzene derivatives, or
oxetane groups), additional cationically curable monomers or
oligomers may be included in the ink vehicle.
[0165] Cationically curable monomers may include, for example,
cycloaliphatic epoxide, and preferably one or more polyfunctional
cycloaliphatic epoxides. The epoxy groups may be internal or
terminal epoxy groups such as those described in WO 02/06371,
incorporated herein by reference. Multifunctional vinyl ethers can
also be used.
[0166] Radically curable monomers may include, for example,
acrylate and methacrylate monomers. As relatively non polar
monomers, mention may be made of isobornyl(meth)acrylate,
lauryl(meth)acrylate, isodecyl(meth)acrylate, caprolactone
acrylate, 2-phenoxyethyl acrylate, isooctyl(meth)acrylate, and
butyl acrylate. In addition, multifunctional acrylate
monomers/oligomers may be used not only as reactive diluents, but
also as materials that can increase the crosslink density of the
cured image, thereby enhancing the toughness of the cured images.
As multifunctional acrylates and methacrylates, mention may be made
of pentaerythritol tetra(meth)acrylate, 1,2 ethylene glycol
di(meth)acrylate, 1,6 hexanediol di(meth)acrylate, 1,12-dodecanol
di(meth)acrylate, tris (2-hydroxy ethyl)isocyanurate triacrylate,
propoxylated neopentyl glycol diacrylate (available from Sartomer
Co. Inc. as SR 9003), hexanediol diacrylate, tripropylene glycol
diacrylate, dipropylene glycol diacrylate, amine modified polyether
acrylates (available as PO 83 F, LR 8869, and/or LR 8889 (all
available from BASF Corporation)), trimethylolpropane triacrylate,
glycerol propoxylate triacrylate, dipentaerythritol
penta-/hexa-acrylate, ethoxylated pentaerythritol tetraacrylate
(available from Sartomer Co. Inc. as SR 494), and the like.
[0167] The reactive diluent material is preferably added to the ink
in amounts of from, for example, 0 to about 80% by weight,
preferably about 1 to about 80% by weight, more preferably about 35
to about 70% by weight, of the ink.
[0168] Radiation curable as used herein is intended to cover all
forms of curing upon exposure to a radiation source, including
light and heat sources and including in the presence or absence of
initiators. Example radiation curing routes include, but are not
limited to, curing using ultraviolet (UV) light, for example having
a wavelength of 200-400 nm or more rarely visible light, preferably
in the presence of photoinitiators and/or sensitizers, curing using
e-beam radiation, preferably in the absence of photoinitiators,
curing using thermal curing, in the presence or absence of high
temperature thermal initiators (and which are preferably largely
inactive at the jetting temperature), and appropriate combinations
thereof.
[0169] The one or more organic gellants function to dramatically
increase the viscosity of the radiation curable phase change ink
within a desired temperature range. In particular, the gellant
forms a semi-solid gel in the ink vehicle at temperatures below the
specific temperature at which the ink is jetted. The semi-solid gel
phase is a physical gel that exists as a dynamic equilibrium
comprised of one or more solid gellant molecules and a liquid
solvent. The semisolid gel phase is a dynamic networked assembly of
molecular components held together by non-covalent bonding
interactions such as hydrogen bonding, Van der Waals interactions,
aromatic non-bonding interactions, ionic or coordination bonding,
London dispersion forces, and the like, which upon stimulation by
physical forces such as temperature or mechanical agitation or
chemical forces such as pH or ionic strength, can reversibly
transition from liquid to semi-solid state at the macroscopic
level. The inks exhibit a thermally reversible transition between
the semi-solid gel state and the liquid state when the temperature
is varied above or below the gel phase transition of the ink. This
reversible cycle of transitioning between semi-solid gel phase and
liquid phase can be repeated many times in the ink formulation.
Mixtures of one or more gellants may be used to effect the
phase-change transition.
[0170] The phase change inks in embodiments may be liquid or solid
at room temperature. It is desired for the phase change radiation
curable inks to have a viscosity of in one embodiment less than
about 50 mPas, in another embodiment less than about 30 mPas, for
example from about 3 to about 30 mPas, in yet another embodiment
from about 5 to about 20 mPas, and in still another embodiment from
about 8 to about 13 mPas, at the temperature of jetting. In some
embodiments, the inks are jetted at low temperatures, such as at
temperatures below 110.degree. C., for example about 40.degree. C.
to about 110.degree. C., in other embodiments from about 50.degree.
C. to about 110.degree. C., and in yet other embodiments from about
60.degree. C. to about 90.degree. C., although the jetting
temperature can be outside this range.
[0171] At such low jetting temperatures, the conventional use of
temperature differential between the jetted ink and the substrate
upon which the ink is jetted in order to effect a rapid phase
change in the ink (i.e., from liquid to solid) may not be
effective. The gellant can thus be used to effect a rapid viscosity
increase in the jetted ink upon the substrate. In particular,
jetted ink droplets would be pinned into position on a receiving
substrate such as an image receiving medium (e.g., paper) or an
intermediate transfer member (e.g., a transfuse drum or belt) that
is at a temperature cooler than the ink jetting temperature of the
ink through the action of a phase change transition in which the
ink undergoes a significant viscosity change from a liquid state to
a gel state (or semi-solid state).
[0172] In embodiments, the temperature at which the ink forms the
gel state is any temperature below the jetting temperature of the
ink, for example any temperature that is about 5.degree. C. or more
below the jetting temperature of the ink In embodiments, the gel
state may be formed at temperatures in one embodiment from about
25.degree. C. to about 100.degree. C., in another embodiment from
about 30.degree. C. to about 70.degree. C., and in yet another
embodiment from about 30.degree. C. to about 50.degree. C.,
although the temperature can be outside this range. There is a
rapid and large increase in ink viscosity upon cooling from the
jetting temperature at which the ink is in a liquid state, to the
gel transition temperature, at which the ink converts to the gel
state. The viscosity increase is in one embodiment at least a
10.sup.2'.sup.5-fold increase in viscosity.
[0173] It has been found that optimum transfer efficiency from an
intermediate transfer surface and optimum print quality may be
achieved if the viscosity of the ink image deposited on the drum is
greatly increased after jetting the ink, so as to obtain a stable
and transferable image that will not smear. A suitable gellant for
the ink would gel the monomers/oligomers in the ink vehicle quickly
and reversibly, and demonstrate a narrow phase-change transition,
for example within a temperature range in one embodiment of about
30.degree. C. to about 100.degree. C., and in another embodiment of
about 30.degree. C. to about 70.degree. C., although the transition
range may also be outside of these temperature ranges. The gel
state of the ink also exhibits in one embodiment a minimum of
10.sup.2'.sup.5 mPas, in another embodiment a minimum of 10.sup.3
mPas, increase in viscosity at preferred transferring temperatures,
e.g., from about 30 to about 70.degree. C., compared to the
viscosity at the jetting temperature. Of particular preference are
gellant containing inks that rapidly increase in viscosity within
5.degree. C. to 10.degree. C. below the jetting temperature and
ultimately reach a viscosity in one embodiment above 10.sup.4 times
the jetting viscosity, and in another embodiment about 10.sup.5
times the jetting viscosity. In direct to paper applications,
increases in viscosity greater than 10.sup.6, while providing
minimal show through or feathering of the image, tend to have
insufficient drop spread and may preserve undesirable artifacts of
jetting, such as drop structure. In intermediate transfer
architectures, the ink image can be spread and smoothed by external
pressure allowing much higher increases in viscosity by the gellant
containing ink. Further, in embodiments that employ intermediate
transfer of the image, the gel ink preferably also has good elastic
properties to enable complete transfer from the drum, a property
which can be inferred from the value of the storage modulus (G'
max) at the transfuse temperature.
[0174] When the inks are in the gel state, the viscosity of the ink
is in one embodiment at least about 1,000 mPas, in another
embodiment at least about 10,000 mPas, and in yet another
embodiment at least about 100,000 mPas. Viscosity values in the gel
state are in the range of in one embodiment from about 10.sup.3 to
about 10.sup.9 mPas, and in another embodiment from about
10.sup.4.5 to about 10.sup.6.5 mPas, although the gel state
viscosity can be outside of these ranges. The desired gel phase
viscosity can vary with the print process. For example, the highest
viscosities are desired when employing intermediate transfer, or
when jetting directly to porous paper in order to minimize the
effects of ink bleed and feathering. On the other hand, less porous
substrates such as plastic may require lower viscosities that
control dot gain and agglomeration of individual ink pixels. The
gel viscosity can be controlled by ink formulation and substrate
temperature. An additional benefit of the gel state for radiation
curable inks is that higher viscosities of about 10.sup.3-10.sup.4
mPas can reduce oxygen diffusion in the ink, which in turn leads to
a faster rate of cure in free radical initiation.
[0175] A plasticizer, which can be either a solid or liquid
plasticizer, such as benzyl phthalates, triaryl phosphate esters,
pentaerythritol tetrabenzoate, dialkyl adipate, dialkyl phthalates,
dialkyl sebacate, alkyl benzyl phthalates, ethylene glycol
monostearate, glycerol monostearate, propylene glycol monostearate,
dicyclohexyl phthalate, diphenyl isophthalate, triphenyl phosphate,
dimethyl isophthalate, and mixtures thereof, or the like can also
be included in the organic phase change carrier. The plasticizer is
present in the organic phase change carrier in any desired or
effective amount, in one embodiment of at least about 0.05% by
weight of the organic phase change carrier, in another embodiment
of at least about 1% by weight of the organic phase change carrier,
and in yet another embodiment of at least about 2% by weight of the
organic phase change carrier, and in one embodiment of equal to or
less than about 15% by weight of the organic phase change carrier,
in another embodiment of equal to or less than about 10% by weight
of the organic phase change carrier, and in yet another embodiment
of equal to or less than about 5% by weight of the organic phase
change carrier, although the amount can be outside of these ranges.
Examples of suitable plasticizers include SANTICIZER.RTM. 278,
SANTICIZER.RTM. 154, SANTICIZER.RTM. 160, SANTICIZER.RTM. 261
(commercially available from Monsanto), and the like or mixtures
thereof.
[0176] A hindered amine antioxidant may be present in the ink in
any desired or effective amount, in one embodiment of at least
about 0.001 percent by weight of the organic phase change carrier,
in another embodiment of at least about 0.05 percent by weight of
the organic phase change carrier, and in yet another embodiment of
at least about 0.10 percent by weight of the organic phase change
carrier, and in one embodiment of equal to or less than about 0.50
percent by weight of the organic phase change carrier, in another
embodiment of equal to or less than about 0.25 percent by weight of
the organic phase change carrier, and in yet another embodiment of
equal to or less than about 0.15 percent by weight of the organic
phase change carrier, although the amount can be outside of these
ranges.
[0177] Examples of suitable hindered amine antioxidants include
those of general formula
##STR00051##
wherein R.sub.1 and R.sub.2 each, independently of the other, can
be a hydrogen atom or an alkyl group, including linear, branched,
saturated, unsaturated, cyclic, substituted, and unsubstituted
alkyl groups, and wherein heteroatoms, such as oxygen, nitrogen,
sulfur, silicon, phosphorus, boron, either may or may not be
present in the alkyl group, in one embodiment with at least 1
carbon atom.
[0178] Specific examples of suitable hindered amine antioxidants
include the following antioxidants commercially available from
Crompton; NAUGUARD.RTM. 445 where
R.sup.1.dbd.R.sup.2.dbd.C(CH.sub.3).sub.2Ph , NAUGUARD.RTM. 635
where R.sub.1.dbd.R.sub.2.dbd.--CH(CH.sub.3)Ph, NAUGUARD.RTM. PS-30
where R.sub.1.dbd.C.sub.4 or C.sub.8, R.sub.2.dbd.C.sub.4 or
C.sub.8 and the like.
[0179] A hindered phenol antioxidant can also be provided. In one
embodiment the hindered phenol is present in a relatively high
concentration. A high concentration of hindered phenol antioxidant
maximizes long term thermal stability by delaying the onset of the
oxidation itself. The hindered phenol antioxidant is present in the
ink in any desired or effective amount, in one embodiment of at
least about 0.01% by weight of the organic phase change carrier, in
another embodiment of at least about 0.5% by weight of the organic
phase change carrier, and in yet another embodiment of at least
about 1.5% by weight of the organic phase change carrier, and in
one embodiment equal to or less than about 4.0% by weight of the
organic phase change carrier, in another embodiment equal to or
less than about 3.0% by weight of the organic phase change carrier,
and in yet another embodiment equal to or less than about 2.5% by
weight of the organic phase change carrier, although the amount can
be outside of these ranges. Specific examples of suitable hindered
phenol antioxidants include ETHANOX.RTM. 330, ETHANOX.RTM. 310,
ETHANOX.RTM. 314, ETHANOX.RTM. 376 (commercially available from
Albemarle) and the like. Also commercially available from Ciba
Specialty Chemicals are IRGANOX.RTM. 1010, IRGANOX.RTM. 1035,
IRGANOX 1076, IRGANOX.RTM. 1330 and the like. Mixtures of two or
more of these hindered phenol antioxidants can also be
employed.
[0180] A dispersant can be present in the ink in any desired or
effective amount for purposes of dispersing and stabilizing the
pigment, and the silica or alternative nanoparticles present in the
ink vehicle. The dispersant is present in any desired or effective
amount, in one embodiment of at least about 1.times.10.sup.-5% by
weight of the organic phase change carrier, in another embodiment
of at least about 1.times.10.sup.-3% by weight of the organic phase
change carrier, and in yet another embodiment of at least about
5.times.10.sup.-1% by weight of the organic phase change carrier,
and in one embodiment equal to or less than about 30% by weight of
the organic phase change carrier, in another embodiment equal to or
less than about 20% by weight of the organic phase change carrier,
and in yet another embodiment equal to or less than about 10% by
weight of the organic phase change carrier, although the amount can
be outside of these ranges. Specific examples of suitable
dispersants are polyalkylene succinimide dispersants such as those
disclosed in US 6,858,070, the disclosure of which is totally
incorporated herein by reference. Dispersants can include the
Chevron Oronite OLOA 11000, OLOA 11001, OLOA 11002, OLOA 11005,
OLOA 371, OLOA 375, OLOA 411, OLOA 4500, OLOA 4600, OLOA 8800, OLOA
8900, OLOA 9000, OLOA 9200 and the like, commercially available
from Chevron Oronite Company LLC, Houston, Tex., as well as
mixtures thereof. Examples of suitable polyalkylene succinimides
and their precursors and methods of making them are disclosed in,
for example, U.S. Pat. No. 3,172,892, U.S. Pat. No. 3,202,678, U.S.
Pat. No. 3,280,034, U.S. Pat. No. 3,442,808, U.S. Pat. No.
3,361,673, U.S. Pat. No. 3,172,892, U.S. Pat. No. 3,912,764, U.S.
Pat. No. 5,286,799, U.S. Pat. No. 5,319,030, U.S. Pat. No.
3,219,666, U.S. Pat. No. 3,381,022, U.S. Pat. No. 4,234,435, and
European Patent Publication 0 776 963, the disclosures of each of
which are totally incorporated herein by reference.
[0181] A rosin ester resin, mixtures thereof, or the like can also
be included in the organic phase change carrier. The rosin ester
resin is present in the organic phase change carrier in any desired
or effective amount, in one embodiment of at least about 0.5% by
weight of the organic phase change carrier, in another embodiment
of at least about 2% by weight of the organic phase change carrier,
and in yet another embodiment of at least about 3% by weight of the
organic phase change carrier, and in one embodiment of equal to or
less than about 20% by weight of the organic phase change carrier,
in another embodiment equal to or less than about 15% by weight of
the organic phase change carrier, and in yet another embodiment
equal to or less than about 10% by weight of the organic phase
change carrier, although the amount can be outside of these ranges.
Examples of suitable rosin ester resins include PINECRYSTAL.RTM.
KE-100 (commercially available from Arakawa), and the like.
[0182] Fatty amides, such as monoamides, diamides, triamides and
tetraamides, mixture thereof, or the like can also be included in
the organic phase change carrier. The amide can be present in one
embodiment in an amount of at least about 1% by weight of the
organic phase change carrier, in another embodiment of at least
about 2% by weight of the organic phase change carrier, and in yet
another embodiment of at least about 3% by weight of the organic
phase change carrier, and in one embodiment equal to or less than
about 30% by weight of the organic phase change carrier, in another
embodiment equal to or less than about 15% by weight of the organic
phase change carrier, and in yet another embodiment equal to or
less than about 5% by weight of the organic phase change carrier,
although the amount can be outside of these ranges. Examples of
suitable amides include stearyl stearamide, a tetra amide resin
obtained from the reaction of one equivalent of dimer acid with two
equivalents of ethylene diamine and UNICID.RTM. 700 (commercially
available from Baker Petrolite), a carboxylic acid derivative of a
long chain alcohol), prepared as described in Example 1 of U.S.
Pat. No. 6,174,937, column 49, line 53 to column 50, line 27, the
entire disclosure of U.S. Pat. No. 6,174,937 being totally
incorporated herein by reference.
[0183] The inks disclosed herein can be obtained by dispersing the
colloidal silica dispersions into the ink components in such a
manner as to maximize uniform dispersion and resist substantial
aggregation. This can include the step of removing a substantial
portion of the solvent from the solvent-silica nanoparticles, and
disseminating the colloidal silica dispersion within the organic
phase change carrier components. More specifically, the method for
producing a low energy phase change ink composition can comprise
combining together an organic phase change carrier comprising a
colloidal dispersion of nanoparticles comprising nanoparticles in a
solvent, at least one curable monomer, a phase change inducing
component and an initiator. The organic phase change carrier
exhibits a substantially uniform distribution of said nanoparticles
discretely distributed therewithin, and exhibits a substantially
increased resistance to aggregation of the nanoparticles
distributed therewithin. The method can comprise combining the
curable monomer, inducing component, and initiator with the
nanoparticles in a solvent while evaporating said solvent to form a
substantially homogeneous solution of said organic phase change
carrier. Then, a colorant is added to the substantially homogeneous
solution of the organic phase change carrier to form the low energy
phase change ink composition.
[0184] The organic phase change carrier can be present in the phase
change ink prepared in any desired or effective amount, in one
embodiment in an amount of at least about 50% by weight of the ink,
in another embodiment of at least about 70% by weight of the ink,
and in yet another embodiment of at least about 90% by weight of
the ink, and in one embodiment equal to or less than about 99% by
weight of the ink, in another embodiment equal to or less than
about 98% by weight of the ink, and in yet another embodiment equal
to or less than about 95% by weight of the ink, although the amount
can be outside of these ranges. In one specific embodiment, the
organic phase change carrier has a melting point of less than about
110.degree. C., and in another embodiment of less than about
100.degree. C., although the melting point of the organic phase
change carrier can be outside of these ranges.
[0185] The phase change ink compositions also contain a colorant.
Any desired or effective colorant can be employed, including dyes,
pigments, mixtures thereof, and the like, provided that the
colorant can be dissolved or dispersed in the ink vehicle. The
phase change carrier compositions can be used in combination with
conventional phase change ink colorant materials, such as Color
Index (C.I.) Solvent Dyes, Disperse Dyes, modified Acid and Direct
Dyes, Basic Dyes, Sulphur Dyes, Vat Dyes, and the like. Examples of
suitable dyes include EASTMAN olefin, USHARECT Blue 86 (Direct Blue
86), available from USHANTI Color; INTRALITE Turquoise 8GL (Direct
Blue 86), available from Classic Dyestuffs; CHEMICTIVE Brilliant
Red 7BH (Reactive Red 4), available from Chemiequip; LEVAFIX Black
EB, available from Bayer; REACTRON Red H8B (Reactive Red 31),
available from Atlas Dye-Chem; D&C Red #28 (Acid Red 92),
available from Warner-Jenkinson; Direct Brilliant Pink B, available
from Global Colors; Acid Tartrazine, available from Metrochem
Industries; CARTASOL Yellow 6GF, available from Clariant; CARTA
Blue 2GL, available from Clariant; metal phthalocyanine colorants
such as those disclosed in U.S. Pat. No. 6,221,137, the disclosure
of which is totally incorporated herein by reference and the like.
Particularly suitable are solvent dyes; within the class of solvent
dyes, spirit soluble dyes are desired because of their
compatibility with the ink vehicles of the present invention.
Examples of suitable spirit solvent dyes include NEOZAPON Red 492
(BASF); ORASOL Red G (Ciba); Direct Brilliant Pink B (Global
Colors); AIZEN SPILON Red C-BH (Hodogaya Chemical); KAYANOL Red 3BL
(Nippon Kayaku); Spirit Fast Yellow 3G; AIZEN SPILON Yellow C-GNH
(Hodogaya Chemical); CARTASOL Brilliant Yellow 4GF (Clariant);
PERGASOL Yellow CGP (Ciba); ORASOL Black RLP (Ciba); SAVINYL Black
RLS (Clariant); MORFAST Black Conc. A (Rohm and Haas); ORASOL Blue
GN (Ciba); SAVINYL Blue GLS (Sandoz); LUXOL Fast Blue MBSN (Pylam);
SEVRON Blue 5GMF (Classic Dyestuffs); BASACID Blue 750 (BASF), and
the like. NEOZAPON Black X51 (C.I. Solvent Black, C.I. 12195)
(BASF), Sudan Blue 670 (C.I. 61554) (BASF), Sudan Yellow 146 (C.I.
12700) (BASF), Sudan Red 462 (C.I. 260501) (BASF), Olefin dyes
(Eastman Chemical Company), and Neopen Blue 808 (BASF), are
particularly suitable in some embodiments. Polymeric dyes can also
be used, such as those disclosed in, for example, U.S. Pat. No.
5,621,022 and U.S. Pat. No. 5,231,135, the disclosures of each of
which are totally incorporated herein by reference, and
commercially available from, for example, Milliken & Company as
Milliken Ink Yellow 12, Milliken Ink Blue 92, Milliken Ink Red 357,
Milliken Ink Yellow 1800, Milliken Ink Black 8915-67, uncut
Reactant Orange X-38, uncut Reactant Blue X-17, Solvent Yellow 162,
Acid Red 52, Solvent Blue 44, and uncut Reactant Violet X-80.
[0186] Pigments are also suitable colorants for the phase change
inks Examples of suitable pigments include Paliogen Violet 5100
(BASF); Paliogen Violet 5890 (BASF); Heliogen Green L8730 (BASF);
Lithol Scarlet D3700 (BASF); Sunfast Blue 15:4 (Sun Chemical
249-0592); Hostaperm Blue B2G-D (Clariant); Permanent Red P-F7RK;
Hostaperm Violet BL (Clariant); Pigment Red 202 (Bayer); Lithol
Scarlet 4440 (BASF); Bon Red C (Dominion Color Company); Oracet
Pink RF (Ciba); Paliogen Red 3871 K (BASF); Sunfast Blue 15:3 (Sun
Chemical 249-1284); Paliogen Red 3340 (BASF); Sunfast Carbazole
Violet 23 (Sun Chemical 246-1670); Lithol Fast Scarlet L4300
(BASF); Sunbrite Yellow 17 (Sun Chemical 275-0023); Heliogen Blue
L6900, L7020 (BASF); Sunbrite Yellow 74 (Sun Chemical 272-0558);
Spectra Pac C Orange 16 (Sun Chemical 276-3016); Heliogen Blue
K6902, K6910 (BASF); Sunfast Magenta 122 (Sun Chemical 228-0013);
Heliogen Blue D6840, D7080 (BASF); Sudan Blue OS (BASF); Neopen
Blue FF4012 (BASF); PV Fast Blue B2GO1 (Clariant); Irgalite Blue
BCA (Ciba); Paliogen Blue 6470 (BASF); Sudan Orange G (Aldrich),
Sudan Orange 220 (BASF); Paliogen Orange 3040 (BASF); Paliogen
Yellow 152, 1560 (BASF); Lithol Fast Yellow 0991 K (BASF); Paliotol
Yellow 1840 (BASF); Novoperm Yellow FGL (Clariant); Lumogen Yellow
D0790 (BASF); Suco-Yellow L1250 (BASF); Suco-Yellow D1355 (BASF);
Suco Fast Yellow D 1355, D 1351 (BASF); Hostaperm Pink E 02
(Clariant); Hansa Brilliant Yellow 5GX03 (Clariant); Permanent
Yellow GRL 02 (Clariant); Permanent Rubine L6B 05 (Clariant); Fanal
Pink D4830 (BASF); Cinquasia Magenta (Du Pont), Paliogen Black
L0084 (BASF); Pigment Black K801 (BASF); and carbon blacks such as
REGAL 330.TM. (Cabot), Carbon Black 5250, Carbon Black 5750
(Columbia Chemical), mixtures thereof and the like. Also suitable
are the colorants disclosed in U.S. Patent 6,472,523, U.S. Patent
6,726,755, U.S. Patent 6,476,219, U.S. Pat. Nos. 6,576,747,
6,713,614, U.S. Pat. No. 6,663,703, U.S. Pat. No. 6,755,902, U.S.
Pat. No. 6,590,082, U.S. Pat. No. 6,696,552, U.S. Pat. No.
6,576,748, U.S. Pat. No. 6,646,111, U.S. Pat. No. 6,673,139, U.S.
Pat. No. 6,958,406, and U.S. Pat. No. 7,053,227, the disclosures of
each of which are totally incorporated herein by reference.
[0187] The colorant is present in the phase change ink in any
desired or effective amount to obtain the desired color or hue, in
one embodiment at least about 0.1% by weight of the ink, in another
embodiment at least about 0.2% by weight of the ink, and in a
further embodiment at least about 0.5% by weight of the ink, and in
one embodiment equal to or less than about 30% by weight of the
ink, in another embodiment equal to or less than about 20% by
weight of the ink, and in a further embodiment equal to or less
than about 10% by weight of the ink, although the amount can be
outside of these ranges.
[0188] The ink compositions disclosed herein in one embodiment have
melting points in one embodiment equal to or less than about
130.degree. C., in another embodiment equal to or less than about
120.degree. C., in a further embodiment equal to or less than about
110.degree. C., and in still another embodiment equal to or less
than about 100.degree. C., although the melting point can be
outside of these ranges.
[0189] The ink compositions prepared by the process disclosed
herein generally have melt viscosities, at the jetting temperature
which can be equal to or less than about 145.degree. C., in one
embodiment equal to or less than about 130.degree. C., and in
another embodiment equal to or less than about 120.degree. C., in a
further embodiment equal to or less than about 110.degree. C., and
in yet another embodiment equal to or less than about 80.degree.
C., although the jetting temperature can be outside of these
ranges, which are in one embodiment equal to or less than about 30
cps, in another embodiment equal to or less than about 25 cps, and
in yet a further embodiment equal to or less than about 20 cps, and
in another embodiment no less than about 2 cps, in a further
embodiment no less than about 3 cps, and in yet a further
embodiment no less than about 4 cps, although the melt viscosity
can be outside of these ranges.
[0190] Showthrough is defined herein as the increase in paper OD
(background subtracted) that results from the presence of a solid
area image on the reverse side of the paper.
[0191] With regard to the subject inks, showthrough can be
substantially reduced so that the printed image in one embodiment
is equal to or less than about 0.07 optical density units, in
another embodiment is equal to or less than about 0.06 optical
density units, in a further embodiment is equal to or less than
about 0.05 optical density units, and in a yet further embodiment
is equal to or less than about 0.04 optical density units, although
the level of showthrough can be outside of these ranges.
[0192] The inks disclosed herein can be employed in apparatus for
direct printing ink jet processes and in indirect (offset) printing
ink jet applications. Another embodiment is directed to a process
which comprises incorporating an ink as disclosed herein into an
ink jet printing apparatus, melting the ink, and causing droplets
of the melted ink to be ejected in an imagewise pattern onto a
recording substrate. A direct printing process is also disclosed
in, for example, U.S. Pat. No. 5,195,430, the disclosure of which
is totally incorporated herein by reference. The inks prepared as
disclosed herein can be employed in apparatus for indirect (offset)
printing ink jet applications. Another embodiment is directed to a
process which comprises incorporating an ink prepared as disclosed
herein into an ink jet printing apparatus, melting the ink, causing
droplets of the melted ink to be ejected in an imagewise pattern
onto an intermediate transfer member, and transferring the ink in
the imagewise pattern from the intermediate transfer member to a
final recording substrate. In a specific embodiment, the
intermediate transfer member is heated to a temperature above that
of the final recording sheet and below that of the melted ink in
the printing apparatus. An offset or indirect printing process is
also disclosed in, for example, U.S. Pat. No. 5,389,958, the
disclosure of which is totally incorporated herein by reference. In
one specific embodiment, the printing apparatus employs a
piezoelectric printing process wherein droplets of the ink are
caused to be ejected in imagewise pattern by oscillations of
piezoelectric vibrating elements.
[0193] Any suitable substrate or recording sheet can be employed,
including plain papers such as XEROX.RTM. 4024 papers, XEROX.RTM.
Image Series papers, Courtland 4024 DP paper, ruled notebook paper,
bond paper, silica coated papers such as Sharp Company silica
coated paper, JuJo paper, Hammermill Laserprint Paper, and the
like, transparency materials, fabrics, textile products, plastics,
polymeric films, inorganic substrates such as metals and wood, and
the like.
[0194] Specific embodiments will now be described in detail. These
examples are intended to be illustrative, and the claims are not
limited to the materials, conditions, or process parameters set
forth in these embodiments.
EXAMPLE I
Synthesis of
Bis[4-(vinyloxy)butyl]trimethyl-1,6-hexanediylbisearbamate (mixture
of 2,2,4- and 2,4,4-isomers)
[0195] To a 2 L three neck flask equipped with a stopper, dropping
funnel, stir bar, and reflux condenser was added
trimethyl-1,6-diisocyanatohexane (mixture of 2,2,4- and
2,4,4-isomers, 118.7 g, 0.57 mol, obtained from Sigma-Aldrich,
Milwaukee, Wis.), dibutyltin dilaurate (3.56 g, 5 6 mmol, obtained
from Sigma-Aldrich) and anhydrous tetrahydrofuran (1 L).
1,4-Butanediol vinyl ether (133.2 g, 1.2 mol, obtained from
Sigma-Aldrich) was added slowly dropwise to the stirring solution
via the addition funnel. The reaction mixture was brought to reflux
and was kept at this temperature until deemed complete by infrared
spectroscopy (about 5 hours, confirmed by the disappearance of the
isocyanate peak at 2200 cm.sup.-1). When the reaction was complete,
methanol (500 mL) was added to quench any residual isocyanate and
the solution was stirred for 0.5 hour. The solvent was stripped in
vacuo and the residual oil was triturated with hexane (3.times.500
mL), dissolved in methylene chloride (1 L), washed with water
(1.times.750 mL), dried over anhydrous magnesium sulfate, filtered,
and concentrated in vacuo to afford 221 g of a pale yellow oil (89
percent yield). The product was believed to be a mixture of
compounds of the formulae
##STR00052##
.sup.1H NMR (300 MHz, CDCl.sub.3): .delta.6.47 (2H, dd, J=14.3, 6.8
Hz), 4.88-4.62 (2H, br. m), 4.19 (2H, dd, J=14.3, 1.8 Hz), 4.09
(4H, br. s), 4.00 (2H, dd, J=6.8, 1.8 Hz), 3.70 (4H, br. s),
3.18-2.91 (4H, m), 1.72-1.01 (13H, m), 1.01-0.88 (9H, m).
EXAMPLE II
[0196] Compounds of the Formula
##STR00053##
wherein --C.sub.34H.sub.56+a-- represents a branched alkylene group
which may include unsaturations and cyclic groups, wherein a is an
integer of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12, including
(but not limited to) isomers of the formula
##STR00054##
were prepared as follows. To a 4 neck, 1 L reaction kettle equipped
with a thermocouple, overhead stirrer, stopper, Dean-Stark trap,
reflux condenser, and argon inlet was added PRIPOL.RTM. 1009 (C36
dimer acid mixture, including isomers of the formula
##STR00055##
as well as other branched isomers which may include unsaturations
and cyclic groups; 850 g, acid number 196 mgKOH/g, 95 wt %,
obtained from Uniqema, New Castle, Del.; further information on C36
dimer acids of this type is disclosed in, for example, "Dimer
Acids," Kirk-Othmer Encyclopedia of Chemical Technology, Vol. 8,
4th Ed. (1992), pp. 223 to 237, the disclosure of which is totally
incorporated herein by reference) and IRGAFOS.RTM. 168
(tris(2,4-di-(tert)-butylphenyl)phosphate, 1.79 g, 0.2 wt %,
obtained from Ciba Specialty Chemicals, Basel, Switzerland). The
system was purged with Ar for 15 minutes with one of the necks
open, after which time the stopper was replaced. The temperature
was set to 100.degree. C. and the stirrer was set in motion. The
stopper was quickly replaced with an addition funnel equipped with
a septum, and ethylene diamine (EDA, 44.6 g, 49 6 mL, 5 wt %,
obtained from Sigma-Aldrich Chemical Company, Milwaukee, Wis.) was
added via syringe. The EDA was added to the reaction mixture slowly
dropwise, ensuring that the internal reaction temperature did not
exceed 118.degree. C. After the addition was complete, the
temperature was raised slowly stepwise to 155.degree. C., where it
was kept until water ceased collecting in the Dean-Stark trap
(about 14 mL H.sub.2O collected; reaction time was 2-3 h at
155.degree. C.). The completion of the reaction was confirmed by
.sup.1H NMR analysis in CDCl.sub.3: the triplet at .delta.2.34,
corresponding to the protons alpha to the carboxylic acid groups,
and the triplet at .delta.2.18, corresponding to the protons alpha
to the carbonyl groups of the amides, were in approximately a 1:1
ratio. At the end of the reaction, the temperature was lowered to
130.degree. C. and the clear, amber oil was poured from the
reaction kettle into aluminum plates (recovered m=867 g). Acid
number =94.8 mgKOH/g. .sup.1H NMR (CDCl.sub.3, 300 MHz) 63.38 (4H,
br. s), 2.53 (2H, br. s), 2.34 (4H, t, J=7.3 Hz), 2.18 (4H, t,
J=7.6 Hz), 1.88-0.65 (136H, m).
EXAMPLE III
[0197] Compounds of the Formula
##STR00056##
wherein --C.sub.34H.sub.56+a-- represents a branched alkylene group
which may include unsaturations and cyclic groups, wherein a is an
integer of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12, including
(but not limited to) isomers of the formula
##STR00057## ##STR00058##
were prepared as follows. To a 3 neck, 2 L flask equipped with two
dropping funnels, stir bar and argon inlet was added the
organoamide prepared in Example II (50 g, acid number 94.8,
n.sub.acid=8.45.times.10.sup.-2 mol), 4-dimethylaminopyridine (1.03
g, 8.45.times.10.sup.-3 mol, obtained from Sigma-Aldrich Chemical
Company, Milwaukee, Wis.), and methylene chloride (850 mL) and the
reaction mixture was stirred until homogenous.
1,3-Dicyclohexylcarbodiimide (101 mL, 1 M solution in
CH.sub.2Cl.sub.2, 1.01.times.10.sup.-1 mol, obtained from
Sigma-Aldrich Chemical Company, Milwaukee, Wis.) was added slowly
dropwise and the reaction mixture was allowed to stir for 0.5 h
before adding caprolactone acrylate (TONE.RTM. M100, 14.52 g,
4.22.times.10.sup.-2 mol, obtained from Dow Chemical Co., Midland,
Mich.) slowly dropwise concurrently with
1-(4-(2-hydroxyethoxy)phenyl)-2-hydroxy-2-methylpropan-1-one
(IRGACURE.RTM. 2959; 9.47 g, 4.22.times.10.sup.-2 mol; obtained
from Ciba Specialty Chemicals, Basel, Switzerland) portionwise. The
reaction progress was followed via .sup.1H NMR spectroscopy in
CDCl.sub.3: when the signals corresponding to the methylene protons
from both alcohols (m, ca. .delta.3.74 from diethylene glycol
methyl ether and m, ca. .delta.4.03 from
1-(4-(2-hydroxyethoxy)phenyl)-2-hydroxy-2-methylpropan-1-one) were
consumed, the reaction was complete. The reaction time was
typically between 2-3 h. The reaction mixture was filtered to
remove N,N'-dicyclohexylurea (byproduct) and the filtrate solvent
was removed in vacuo. Methanol (250 mL) was added to the residue
and a biphasic mixture formed that was transferred to a separatory
funnel. The bottom layer was removed, dissolved in CH.sub.2Cl.sub.2
(250 mL), dried over MgSO.sub.4 and filtered. The solvent was
removed in vacuo to reveal a sticky, pale yellow solid (47.1 g).
.sup.1H NMR (CDCl.sub.3, 300 MHz) .delta.8.08 (2H, d, J=8.7 Hz),
6.97 (2H, d, J=8.7 Hz), 6.47 (1H, d, J=17.4 Hz), 6.15 (1H, dd,
J=17.4, 10.4 Hz), 5.89 (1H, d, J=10.4 Hz), 4.47 (2H, t, J=4.6 Hz),
4.40-4.23 (6H, m), 4.08 (4H, t, J=6.6 Hz), 3.37 (4H, s), 2.69-2.45
(3H, br. s), 2.45-2.26 (8H, m), 2.19 (4H, t, J=7.3 Hz), 1.99-0.83
(160H, m).
EXAMPLE IV
Synthesis of Epoxy-Polyamide Composite Gellant
[0198] In a 200 mL round bottom flask equipped with reflux
condenser, thermometer and addition funnel, was charged a bisphenol
A-co-epichlorohydrin epoxy resin commercially available from Dow
Chemical as DER 383 resin (10.0 g, or 40% by weight of total
material), a polyamide resin VERSAMID 795 available from Cognis
Corp. (10.0 g, or 40% by weight), and triphenylphosphine as
catalyst (0.0875 g, or 0.35% by weight). The mixture was heated to
90.degree. C. and stirred for 1 hour, after which time was first
added a prepared solution of acrylic acid (2.58 g, 10.35% by
weight) and 4-methoxyphenol as polymerization inhibitor (0.0125 g,
0.05% by weight), followed with a second prepared solution
containing lauric acid (1.0625 g, 4.25% by weight) and
triphenylphosphine (0.0875 g, 0.35% by weight). The temperature of
the reaction mixture was increased to 115.degree. C. and stirred
for an additional 3 hours, thereby forming the acrylate-modified
epoxy-polyamide composite gellant. The product was obtained as a
clear, pale yellow gelatinous material.
INK EXAMPLE I
[0199] To an aluminum pan was added 88.6 g of
bis[4-(vinyloxy)butyl]trimethyl-1,6-hexanediylbiscarbamate (mixture
of 2,2,4- and 2,4,4-isomers) and 15.0 g of R-GEN.RTM. BF-1172
(cationic photoinitiator; substituted triarylsulfonium
hexafluorophosphate salt in propylene carbonate as a 40% solution;
obtained from Chitec Chemical Co., Ltd., Taiwan, R.O.C.). The
mixture was stirred at 100.degree. C. until homogenous (about 0.5
hour). The temperature was then raised to 110.degree. C., 45.0 g of
1-octadecanol (obtained from Sigma-Aldrich, Milwaukee, Wis.) was
added, and the reaction mixture was stirred until homogeneous
(about 15 minutes), after which time 1.52 g of Red Olefin Dye 24900
(obtained from Eastman Chemical Company, Kingsport, Tenn.) was
added and the reaction mixture was stirred for an additional 1
hour.
INK EXAMPLE II
[0200] To a beaker was added 7.5 g of the amide gellant synthesized
in Example III and 70.8 g of SR9003 (propoxylated neopentyl glycol
diacrylate, obtained from Sartomer Co. Inc., Exton, Pa.). The
mixture was stirred at 90.degree. C. for 1 h. The resulting
solution was filtered to 0.22 pm at 90.degree. C., let cool to RT
overnight, remelted and filtered to 0.22 .mu.m at 90.degree. C. To
the resulting solution was added 3.0 g Irgacure 379
(2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-ylphenyl)-butanone;
obtained from Ciba Specialty Chemicals, Tarrytown, N.Y.), 2.0 g
Darocur ITX (Isopropyl-9H-thioxanthen-9-one; obtained from Ciba
Specialty Chemicals, Tarrytown, N.Y.), 1.0 g Irgacure 819
(bis(2,4,6-trimethylbenzoyl)-phenyl-phosphine oxide; obtained from
Ciba Specialty Chemicals, Tarrytown, N.Y.), 3.5 g Irgacure 127
(2-Hydroxy-1-(4-(4-(2-hydroxy2-methylpropionyl)-benzyl)-phenyl)-2-methylp-
ropan-1-one; obtained from Ciba Specialty Chemicals, Tarrytown,
N.Y.) and 0.2 g Irgastab UV10 (obtained from Ciba Specialty
Chemicals, Tarrytown, N.Y.) and the entire solution was stirred for
1 h at 90.degree. C. The ink base was filtered to 0.22 .mu.m and
the hot solution (90.degree. C.) was added dropwise to a stirring
solution of 12.0 g of a blue pigment dispersion (25wt %, obtained
from Sun Chemical, Parsippany, N.J.), also at 90.degree. C. The
resulting ink was filtered to 6 .mu.m.
INK EXAMPLE III
[0201] While stirring at 90.degree. C., the epoxy-polyamide
composite gellant synthesized in Example IV (8 parts) was first
dissolved in SR9003 (propoxylated neopentylglycol diacrylate, 29.8
parts) and caprolactone acrylate (15 parts) to which was added a
mixture of photoinitiators consisting of
2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)-benzyl)-phenyl)-2-methylp-
ropan-1-one (3.5 parts),
2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-ylphenyl)-butanone
(3 parts), bis(2,4,6-trimethylbenzoyl)-phenyl-phosphine oxide (1
part) and isopropyl-9H-thioxanthen-9-one (2 parts) followed by
IRGASTAB LTV 10 (0.2 parts) obtained from Ciba Specialty Chemicals,
followed lastly by 37.5 parts Pigment Red 202 dispersion consisting
86.67 percent propoxylated neopentylglycol diacrylate, 8% Pigment
Red 202 (Bayer Corporation, Rockhill, S.C.) and 5.9% Solsperse
34750.
INK EXAMPLES IV TO VI
[0202] A number of phase change carriers and inks containing
substantially non aggregated silica nanoparticles are prepared by a
solvent exchange process in which 1) silica nanoparticles dispersed
in a low boiling point solvent are added slowly to Ink Examples I
to III while maintaining the temperature just below the boiling
point of the solvent; 2) the solvent is removed slowly by stirring
the carrier or ink at about the boiling point of the solvent.
INK EXAMPLE IV
[0203] To an aluminum pan was added 88.6 g of
bis[4-(vinyloxy)butyl]trimethyl-1,6-hexanediylbiscarbamate (mixture
of 2,2,4- and 2,4,4-isomers) and 15.0 g of R-GEN.RTM. BF-1172
(cationic photoinitiator; substituted triarylsulfonium
hexafluorophosphate salt in propylene carbonate as a 40% solution;
obtained from Chitec Chemical Co., Ltd., Taiwan, R.O.C.). The
mixture was stirred at 100.degree. C. until homogenous (about 0.5
hour). The temperature was then raised to 110.degree. C., 45.0 g of
1-octadecanol (obtained from Sigma-Aldrich, Milwaukee, Wis.) was
added, and the reaction mixture was stirred until homogeneous
(about 15 minutes), after which time 1.52 g of Red Olefin Dye 24900
(obtained from Eastman Chemical Company, Kingsport, Tenn.) was
added and the reaction mixture was stirred for an additional 1
hour. The temperature was then reduced to about 75-80 degree C. and
43.54 g of a silica dispersion in methyl ethyl ketone (MEK) (MEK-ST
Organosilicasol.TM., obtained from Nissan Chemicals Industry, about
13.06 grams of dry silica nanoparticles, was slowly added. The
resulting solvent-containing dispersion was stirred for 2 hours at
about 80 degree C., the MEK solvent being slowly evaporated to
yield a silica containing organic phase change ink.
INK EXAMPLE V
[0204] To a beaker was added 7.5 g of the amide gellant synthesized
in Example III and 70.8 g of SR9003 (propoxylated neopentyl glycol
diacrylate, obtained from Sartomer Co. Inc., Exton, Pa.). The
mixture was stirred at 90.degree. C. for 1 h. The resulting
solution was filtered to 0.22 pm at 90.degree. C., let cool to RT
overnight, remelted and filtered to 0.22 .mu.m at 90.degree. C. To
the resulting solution was added 3.0 g Irgacure 379
(2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-ylphenyl)-butanone;
obtained from Ciba Specialty Chemicals, Tarrytown, N.Y.), 2.0 g
Darocur ITX (Isopropyl-9H-thioxanthen-9-one; obtained from Ciba
Specialty Chemicals, Tarrytown, N.Y.), 1.0 g Irgacure 819
(bis(2,4,6-trimethylbenzoyl)-phenyl-phosphine oxide; obtained from
Ciba Specialty Chemicals, Tarrytown, N.Y.), 3.5 g Irgacure 127
(2-Hydroxy-1-(4-(4-(2-hydroxy2-methylpropionyl)-benzyl)-phenyl)-2-methylp-
ropan-1-one; obtained from Ciba Specialty Chemicals, Tarrytown,
N.Y.) and 0.2 g Irgastab UV 10 (obtained from Ciba Specialty
Chemicals, Tarrytown, N.Y.) and the entire solution was stirred for
1 h at 90.degree. C. The ink base was filtered to 0.22 .mu.m and
the hot solution (90.degree. C.) was added dropwise to a stirring
solution of 12.0 g of a blue pigment dispersion (25wt %, obtained
from Sun Chemical, Parsippany, N.J.), also at 90.degree. C. The
temperature was then reduced to about 75-80 degree C. and 43.54 g
of a silica dispersion in methyl ethyl ketone (MEK) (MEK-ST
Organosilicasol.TM., obtained from Nissan Chemicals Industry, about
13.06 grams of dry silica nanoparticles, was slowly added. The
resulting solvent-containing dispersion was stirred for 2 hours at
about 80 degree C., the MEK solvent being slowly evaporated to
yield a silica containing organic phase change ink. The resulting
ink was filtered to 6 .mu.m.
INK EXAMPLE VI
[0205] (Part A) A silica containing carrier was prepared as
follows: (1) To a 200 ml beaker was added 90 parts of SR9003
(propoxylated neopentylglycol diacrylate) and then slowly added
43.54 g of a silica dispersion in methyl ethyl ketone (MEK) (MEK-ST
Organosilicasol.TM. obtained from Nissan Chemicals Industry, about
13.06 grams of dry silica nanoparticles, the temperature being
maintained at about 75-80 degree C.; (2) the resulting
solvent-containing vehicle was stirred for 2 hours at about 80
degree C., the MEK solvent being slowly evaporated to yield a
silica-containing SR9003 carrier.
[0206] (Part B) While stirring at 90.degree. C., the
epoxy-polyamide composite gellant synthesized in Example IV (8
parts) was first dissolved in the SR9003 carrier of part A (29.8
parts) and caprolactone acrylate (15 parts) to which was added a
mixture of photoinitiators consisting of
2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)-benzyl)-phenyl)-2-methylp-
ropan-1-one (3.5 parts),
2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-ylphenyl)-butanone
(3 parts), bis(2,4,6-trimethylbenzoyl)-phenyl-phosphine oxide (1
part) and isopropyl-9H-thioxanthen-9-one (2 parts) followed by
IRGASTAB UV 10 (0.2 parts) obtained from Ciba Specialty Chemicals,
followed lastly by 37.5 parts Pigment Red 202 dispersion consisting
86.67 percent propoxylated neopentylglycol diacrylate, 8% Pigment
Red 202 (Bayer Corporation, Rockhill, S.C.) and 5.9% Solsperse
34750.
INK EXAMPLE VII
[0207] To a glass beaker was added (1) 59.35 grams of
bis[4-(vinyloxy)butyl]trimethyl-1,6-hexanediylbiscarbamate (mixture
of 2,2,4- and 2,4,4-isomers); (2) 12.49 grams of
bis[4-(vinyloxy)butyl]dodecanedioate, and then slowly (3) 43.54 g
of a silica dispersion in methyl ethyl ketone (MEK) (MEK-ST
Organosilicasol.TM., obtained from Nissan Chemicals Industry, about
13.06 grams of dry silica nanoparticles, the temperature being
maintained at about 75-80 degree C.; (4) the resulting
solvent-containing dispersion was stirred for 2 hours at about 80
degree C., the MEK solvent being slowly evaporated to yield a
silica-containing monomer mixture. To this monomer mixture was
added (5) 8.29 grams of R-GEN.RTM. BF-1172 (cationic
photoinitiator; substituted triarylsulfonium hexafluorophosphate
salt in propylene carbonate as a 40% solution; obtained from Chitec
Chemical Co., Ltd., Taiwan, R.O.C.); (6) 11.45 grams of
VEctomer.RTM. 5015 (obtained from Sigma-Aldrich, Milwaukee, Wis.)
and (7) 12.50 grams of 1-octadecanol (obtained from Sigma-Aldrich).
The resulting mixture was further heated with stirring at
100.degree. C. until visually homogenous (about 1 hour). At this
point, 0.94 grams of Neopen Blue 808 dye (obtained from BASF
Aktiengesellschaft, Ludwigshafen, Germany) was added and the
mixture was stirred with heating for an additional 1 hour.
INK EXAMPLE VIII
[0208] To a glass beaker was added 55.82 grams of
bis[4-(vinyloxy)butyl]trimethyl-1,6-hexanediylbiscarbamate (mixture
of 2,2,4- and 2,4,4-isomers), 10.93 grams of
bis[4-(vinyloxy)butyl[dodecanedioate and 31.74 grams of
hydrogenated Castor oil (obtained from Campbell and Co.,
Charlemont, Mass.). The mixture was heated at 110.degree. C. until
all ingredients dissolved (about 0.5 hour). The temperature was
then lowered to 100.degree. C., 10.95 grams of R-GEN.RTM. BF-1172
(cationic photoinitiator; substituted triarylsulfonium
hexafluorophosphate salt in propylene carbonate as a 40% solution;
obtained from Chitec Chemical Co., Ltd., Taiwan, R.O.C.) was added,
and the reaction mixture was stirred until homogeneous (about 0.5
hour). The temperature was then reduced to about 75-80 degree C.
and 43.54 g of a silica dispersion in methyl ethyl ketone (MEK)
(MEK-ST Organosilicasol.TM., obtained from Nissan Chemicals
Industry, about 13.06 grams of dry silica nanoparticles, was slowly
added. The resulting solvent-containing dispersion was stirred for
2 hours at about 80 degree C., the MEK solvent being slowly
evaporated to yield a silica containing organic phase change
carrier. At this point, 0.55 grams of Red Olefin Dye 24900
(obtained from Eastman Chemical Company, Kingsport, Tenn.) was
added and the mixture was stirred with heating for an additional 1
hour.
INK EXAMPLE IX
[0209] To a glass beaker was added 67.49 grams of
bis[4-(vinyloxy)butyl]trimethyl-1,6-hexanediylbiscarbamate (mixture
of 2,2,4- and 2,4,4-isomers), 6.25 grams of VEctomer.RTM. 3080
(obtained from Sigma-Aldrich, Milwaukee, Wis.), and 12.54 grams of
R-GEN.RTM. BF-1172 (cationic photoinitiator; substituted
triarylsulfonium hexafluorophosphate salt in propylene carbonate as
a 40% solution; obtained from Chitec Chemical Co., Ltd., Taiwan,
R.O.C.). The reaction mixture was heated at 90.degree. C. with
stirring until homogeneous (about 15 minutes). At this point, the
temperature was raised to 100.degree. C., 37.50 grams of
1-octadecanol was added, and the mixture was stirred until
homogeneous (about 0.5 hour). The temperature was then reduced to
about 75-80 degree C. and 43.54 g of a silica dispersion in methyl
ethyl ketone (MEK) (MEK-ST Organosilicasol.TM., obtained from
Nissan Chemicals Industry, about 13.06 grams of dry silica
nanoparticles, was slowly added. The resulting solvent-containing
dispersion was stirred for 2 hours at about 80 degree C., the MEK
solvent being slowly evaporated to yield a silica containing
organic phase change carrier. At this point, 1.25 grams of Blue
Olefin Dye 24316 (obtained from the Eastman Chemical Company,
Kingsport, Tenn.) was added and the formulation was stirred for 1
hour longer.
[0210] The nanoparticles containing inks of the invention can be
obtained by variations of the process described in Ink Examples IV
to IX; in specific embodiments, the nanoparticles are added to all
or part of the phase change vehicle prior to the addition of the
colorant. If the nanoparticles are dispersed in a low boiling point
solvent, said solvent is evaporated before the addition of the
colorant, optionally the initiator and/or phase change inducing
component can be added after the nanoparticles are added to the
vehicles. When self-dispersible nanoparticles are selected, these
nanoparticles are dispersed in the vehicle prior to the addition of
the other ink components, optionally high shear mixing and/or
ultrasound and/or dispersants are used to assist in the dispersion
of the nanoparticles into the ink.
[0211] It will be appreciated that various of the above-disclosed
and other features and functions, or alternatives thereof, may be
desirably combined into many other different systems or
applications. Also that various presently unforeseen or
unanticipated alternatives, modifications, variations or
improvements therein may be subsequently made by those skilled in
the art which are also intended to be encompassed by the following
claims.
* * * * *