U.S. patent application number 09/847909 was filed with the patent office on 2001-12-13 for easily cleanable polymer laminates.
This patent application is currently assigned to OMNOVA Solutions Inc.. Invention is credited to Callicott, Marten S., Gottschalk, Daniel C., Hyde, David L., Kausch, Charles M., Medsker, Robert E., Verrocchi, Anthony, Weinert, Raymond J., Woodland, Daniel D., Wright, Joe A..
Application Number | 20010051280 09/847909 |
Document ID | / |
Family ID | 21883642 |
Filed Date | 2001-12-13 |
United States Patent
Application |
20010051280 |
Kind Code |
A1 |
Callicott, Marten S. ; et
al. |
December 13, 2001 |
Easily cleanable polymer laminates
Abstract
A substrate having an adherent and stain resistant layer having
durability and flexibility, said layer comprising the reaction
product of a reactive polyester having free carboxylic acid and/or
hydroxyl groups, a hydroxyl terminated polymer including repeat
units from an oxetane having pendant
--CH.sub.2--O--(CH.sub.2).sub.n--Rf groups (said Rf groups
generally being a fluorinated alkyl group) and an amino resin
curative. The substrate may be printed or embossed or both. The
coated substrate has both stain resistant properties and dry erase
properties with dry erase markers. The coated substrate can be used
as prepared or applied to other substrates.
Inventors: |
Callicott, Marten S.;
(Columbus, MS) ; Hyde, David L.; (Columbus,
MS) ; Kausch, Charles M.; (Akron, OH) ;
Verrocchi, Anthony; (Akron, OH) ; Wright, Joe A.;
(Starkville, MS) ; Weinert, Raymond J.;
(Macedonia, OH) ; Medsker, Robert E.; (Hartville,
OH) ; Woodland, Daniel D.; (Munroe Falls, OH)
; Gottschalk, Daniel C.; (Columbus, OH) |
Correspondence
Address: |
Robert F. Rywalski, Esq.
OMNOVA Solutions Inc.
175 Ghent Road
Fairlawn
OH
44333-3300
US
|
Assignee: |
OMNOVA Solutions Inc.
|
Family ID: |
21883642 |
Appl. No.: |
09/847909 |
Filed: |
May 2, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09847909 |
May 2, 2001 |
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09244711 |
Feb 4, 1999 |
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09244711 |
Feb 4, 1999 |
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09035595 |
Mar 5, 1998 |
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Current U.S.
Class: |
428/483 ;
428/480 |
Current CPC
Class: |
Y10T 428/31797 20150401;
Y10T 428/31786 20150401; C09D 167/00 20130101; Y10T 428/31794
20150401; C08G 18/10 20130101; C08G 18/5015 20130101; C08G 65/18
20130101; C08G 65/226 20130101; Y10T 428/31681 20150401; C09D
167/00 20130101; C08L 2666/14 20130101; C08G 18/10 20130101; C08G
18/46 20130101 |
Class at
Publication: |
428/483 ;
428/480 |
International
Class: |
B32B 027/36; B32B
027/06 |
Claims
What is claimed:
1. A laminate comprising 1) a substrate 2) a stain resistant and
adherent layer on said substrate, comprising the cross-linked
reaction product of at least; a) at least one amino resin
cross-linking agent and either b1) reactive polyester resin and b2)
a hydroxyl terminated polymer including repeat units from an
oxetane having a pendant --CH.sub.2--O--(CH.sub.2).s- ub.n--Rf
group or c) a reactive polyester resin including therein at least
one repeat unit derived from copolymerizing into said polyester a
hydroxyl terminated polymer including repeat units from an oxetane
having a pendant --CH.sub.2--O--(CH.sub.2).sub.n--Rf group, or
combinations of a), b), or c), wherein said Rf group,
independently, being a linear or branched alkyl group of 1 to 20
carbon atoms and a minimum of 25 percent of the hydrogen atoms of
said alkyl group being replaced by F, or said Rf group,
independently, being a oxaperflourinated or perfluorinated
polyether having from 4 to 60 carbon atoms, and n being from 1 to 3
and optionally, up to 20 wt %, based on the weight of said hydroxyl
terminated polymer, of a cyclic tetramer from the polymerization of
an oxetane monomer having a pendant
--CH.sub.2--O--(CH.sub.2).sub.n--Rf group wherein Rf is described
above.
2. A laminate according to claim 1 wherein a surface of said
substrate has been printed at least one time.
3. A laminate according to claim 1, wherein a surface of said
substrate has been embossed.
4. A laminate according to claim 1, wherein a surface of said
substrate has been both printed and embossed.
5. A laminate according to claim 1, wherein the surface of said
substrate includes a layer of plasticized vinyl chloride
polymer.
6. A laminate according to claim 1, wherein said substrate
comprises a cellulosic product, fibers, synthetic polymers, metal
or ceramic.
7. A laminate according to claim 1, wherein said Rf group is
independently a linear or branched perfluorinated alkyl group of 1
to 20 carbon atoms.
8. A laminate according to claim 7, wherein said hydroxyl
terminated polymer includes repeat units from oxetanes and repeat
units from tetrahydrofuran.
9. A laminate according to claim 7, wherein said second layer has
the characteristic of being easily cleaned of undesired markings
without using liquids.
10. The method which comprises; 1) applying to a substrate a layer
of a catalyzed mixture of at least a) one amino resin cross-linking
agent and either b1) a reactive polyester resin and b2) a hydroxyl
terminated polymer including repeat units from an oxetane having a
pendant --CH.sub.2--O--(CH.sub.2).sub.n--Rf group or c) a reactive
polyester resin including at least one repeat unit derived from
copolymerizing into said polyester a hydroxyl terminated polymer
including repeat units from an oxetane having a pendant
--CH.sub.2--O--(CH.sub.2).sub.n--Rf group, or combinations of a),
b), and c) 2) subsequently heating said mixture to at least about
150.degree. F. for a period of time sufficient to cure and
cross-link said layer, thereby providing a crosslinked layer,
wherein said Rf group, independently is a linear or branched alkyl
group of 1 to 20 carbon atoms with a minimum of 25 percent of the
hydrogens of said alkyl groups being replaced by F or said Rf group
independently being an oxaperfluorinated or perfluorinated
polyether having from 4 to 60 carbon atoms, and n being from 1 to
3.
11. A method according to claim 10, wherein said Rf of said repeat
units is individually on said repeat units a perfluorinated alkyl
having from 1 to 20 carbon atoms.
12. A method according to claim 10, where prior to applying said
layer to said substrate, said substrate is printed at least one
time.
13. A method according to claim 10, wherein said substrate
comprises a cellulosic product, fibers, synthetic polymer, metal or
ceramic.
14. A method according to claim 10, where prior to applying said
layer to said substrate, said substrate is printed and
embossed.
15. A method according to claim 10, wherein said substrate includes
a layer of plasticized vinyl chloride polymer.
16. A method according to claim 15, wherein said vinyl chloride
polymer is coated onto a fabric or backing.
17. A method according to claim 15, of forming a wallcovering.
18. A method according to claim 11 of forming a dry erase
surface.
19. A composition, comprising; a) at least one amino resin
cross-linking agent and either b1) reactive polyester resin and b2)
a hydroxyl terminated polymer including repeat units from an
oxetane having a pendant --CH.sub.2--O--(CH.sub.2).sub.n--Rf group,
or c) a reactive polyester resin including therein at least one
repeat unit derived from copolymerizing into said polyester a
hydroxyl terminated polymer including repeat units from an oxetane
having a pendant --CH.sub.2--O--(CH.sub.2).sub.n--Rf group or
combinations of a), b), and c), wherein said pendant
--CH.sub.2--O--(CH.sub.2).sub.n--Rf group, independently, on
different repeat units is a linear or branched alkyl group of 1 to
20 carbon atoms, a minimum of 25 percent of the hydrogen atoms of
said alkyl group being replaced by F or said Rf group
independently, being an oxaperfluorinated or perfluorinated
polyether having from 4 to 60 carbon atoms, and n is from 1 to
3.
20. A composition according to claim 19, wherein Rf is said linear
or branched alkyl group.
21. A composition according to claim 19, wherein said Rf is a
linear or branched alkyl group of 3 to 10 carbon atoms.
22. A composition according to claim 19, wherein at least said
amino resin and said polyester including repeat units from said
hydroxyl terminated polymer are reacted together to form a reaction
product.
23. A composition according to claim 21, wherein at least said
polyester, said hydroxyl terminated polymer, and said amino resin
are reacted together to form a reaction product.
24. In an article including a substrate having a protective coating
thereon, the improvement wherein the protective coating comprises
a) at least one amino resin cross-linking agent and either b1)
reactive polyester resin and b2) a hydroxyl terminated polymer
including repeat units from an oxetane having a pendant
--CH.sub.2--O--(CH.sub.2).sub.n--R- f group or c) a reactive
polyester resin including therein at least one repeat unit derived
from copolymerizing into said polymester a hydroxyl terminated
polymer including repeat units from an oxetane having a pendant
--CH.sub.2--O--(CH.sub.2).sub.n--Rf group, or combinations of a),
b), and c), wherein said pendant --CH.sub.2--O--(CH.sub.2).sub.nRF
group independently on different repeat units is a linear or
branched alkyl group of 1 to 20 carbon atoms and a minimum of 25
percent of the hydrogen atoms of said alkyl group being replaced by
F or said Rf, independently, being an oxaperfluorinated or
perfluorinated polyether having from 4 to 60 carbon atoms, and in
being from 1 to 3.
25. In an article according to claim 24 wherein said a) and c) are
reacted to form a crosslinked composition.
26. In an article according to claim 25, wherein the substrate is a
cellulosic sheet.
Description
[0001] This application is a continuation-in-part of prior
application Ser. No. 09/035,595, filed Mar. 5, 1998, entitled
Easily Cleanable Polymer Laminates, which is herein incorporated by
reference.
FIELD OF INVENTION
[0002] This invention relates to laminates having improved stain
resistance due to the incorporation of a polymer having repeat
units from an oxetane monomer having pendant fluorinated groups
into a stain resistant surface layer. The stain resistant layer can
also be adhered to a variety of substrates including polyesters,
paper, polyolefins etc. The coatings exhibit dry erase
characteristics when dry erase markers are used.
BACKGROUND OF INVENTION
[0003] U.S. Pat. No. 4,603,074 sets forth a polyester-amino resin
composition that can form a stain resistant layer on plasticized
polyvinyl chloride substrates. While this coating was very good
with respect to stain resistance and abrasion resistance, it would
be desirable to have further increases in cleanability without
using solvents, while maintianing stain resistance and abrasion
resistance.
[0004] A variety of polymeric coatings and surface treatments for
natural and synthetic materials have been developed to enhance the
dirt and stain release characteristics. Some of the more effective
ones to date allow for reapplication of the anti-soil treatment
after cleaning (such as with carpets) or in tents.
[0005] Dry erase boards and ink or marker pens therefore are
popular replacements for chalkboards. A variety of relatively
nonporous writing surfaces have been developed along with special
dry erase markers that are specially designed to leave strong well
defined continuous marks that can be erased with a dry cloth or
eraser. U.S. Pat. Nos. 3,834,823; 3,922,457; 3,949,132; 4,746,576;
4,988,123 and 5,324,764; disclose such technology and are herein
incorporated by reference for their teachings on dry erase
systems.
[0006] U.S. Pat. No. 5,650,483 describes the preparation of oxetane
monomers useful to form oxetane polymers with pendant fluorinated
chains. The oxetane polymers were characterized as having low
surface energy, high hydrophobicity, and a low coefficient of
friction. That patent is incorporated by reference herein for its
teachings on how to prepare the oxetane monomers and polymers. In
the reference the oxetane polymers could be formulated with
isocyanates to form crosslinked compositions. Additional patents
issued on variations of the oxetane monomers and polymers. These
were U.S. Pat. Nos. 5,654,450; 5,663,289; 5,668,250, and 5,668,251
also incorporated herein by reference.
SUMMARY OF INVENTION
[0007] According to the present invention, an improved stain and
abrasion resistant polymeric layer was developed by incorporating a
minor amount of a hydroxyl terminated polymer having repeat units
from an oxetane monomer having pendant fluorinated groups thereon
into a polyester-amino resin composition. The hydroxyl terminated
polymer may have other repeat units such as derived from the ring
opening polymerization of cyclic ethers including tetrahydrofuran
and/or more conventional ring opening polymerization of oxetane or
epoxy monomers. Excellent stain release and abrasion release are
observed with as little as 0.1, 0.2 or 0.5 to 10 or 15 parts by
weight of repeat units from the oxetane monomer with pendant
fluorocarbon groups based on 100 parts of polyester resin and amino
resin in the dry coating. The coating may be as thin as 0.1 to 2 or
4 mil (thousandths of an inch) thick. One preferred embodiment is a
layer of a flexible vinyl chloride polymer coated with said
polyester-amino resin composition in solvent and heated to cure and
adhere the resin to the vinyl chloride polymer layer with removal
of the solvent. This provides the flexible vinyl chloride polymer
layer with a coating which is stain resistant or which can readily
be cleaned (either dry or with solvent) without significant
abrasion to remove stains.
[0008] The vinyl chloride layer may be a vinyl chloride polymer,
which is a plastisol coated and fused or is a plasticized vinyl
chloride polymer composition which has been calendered or extruded.
The vinyl chloride may be applied to a backing, substrate or
support. In either case the polyvinyl chloride layer (about 1 to 30
or 100 mils thick) can be printed one or more times. The printed
layer can be embossed, before and/or after printing, and finally
coated with a layer of a solution of a said polyester-amino resin
composition and cured to provide the vinyl chloride polymer layer
with an outer stain resistant layer about 0.1 to 2 or 4 mils or
more thick.
DISCUSSION OF DETAILS AND PREFERRED EMBODIMENTS
[0009] The reactive polyester-amino resin for use as the outer or
top coating on a substrate is prepared from a solution of a
reactive polyester (alkyd resin) and an amino resin in a solvent
(such as methyl ethyl ketone, water, alcohols, or combination
thereof) containing a catalyst such as p-toluene sulfonic acid and
is applied at a temperature desirably of at least about 150, 200,
250, or 400.degree. F. or more (66, 93, 121 or 204.degree. C.) to
cause curing or cross-linking of the polyester resin and the amino
resin. The reactive polyester-amino resin composition may be
applied to a substrate (e.g. vinyl chloride polymer, polyester,
cellulosic, polyolefin composition) directly or with an
intermediate tie layer. The substrate may be with or without a
backing or substrate, with or without the printing and with or
without the embossing. A preferred embodiment includes the
catalyzed reactive polyester-amino resin solution being applied
over a tie layer to an embossed and printed compounded and
plasticized vinyl chloride polymer composition carried on a
suitable backing or substrate. Such vinyl chloride polymer based
substrates are readily available from wallcovering
manufacturers.
[0010] The polyester resins (alkyd resins) are made by a
condensation polymerization reaction, usually with heat in the
presence of a catalyst, or a mixture of a polybasic acid and a
polyhydic alcohol. Fatty monobasic oils or fatty acids, monohydroxy
alcohols and anhydrides may be present. The polyester contains
active hydrogen atoms, e.g., carboxylic acid groups and/or hydroxyl
groups for reaction with the amino resin. Example of some acids to
use to form the alkyd resin or reactive polyester are adipic acid,
azelaic acid, sebacic acid, terephthalic acid, phthalic anhydride,
and so forth. Examples of some polybasic alcohols include ethylene
glycol, propylene glycol, diethylene glycol, dipropylene glycol,
glycerine, butylene glycol, 2,2-dimethyl-1,3-propanediol,
trimethylol propane, 1,4-cyclohexanedimethanol, pentaerythritol,
trimethylolethane and the like. Mixtures of the polyols and
polycarboxylic acids can be used. An example of a suitable reactive
polyester is the condensation product of trimethylol propane,
2,2-dimethyl-1,3-propanediol, 1,4-cyclohexanedimethanol, phthalic
anhydride and adipic acid. Mixtures of these reactive polyester or
alkyd resins can be used. Alkyd resins are well known as shown by
the "Encyclopedia of Polymer Science and Technology," Vol. 1, 1964,
John Wiley & Sons, Inc., pages 663-734; "Alkyd Resins,"
Martens, Reinhold Publishing Corporation, New York, 1961 and "Alkyd
Resin Technology," Patton, Interscience Publishers, a division of
John Wiley and Sons, New York, 1962. Some unsaturated polybasic
acids and unsaturated polyols may be used in the condensation
reaction but are generally undesirable. The reactive polyester
(alkyd resin) is usually added to the amino resin while dissolved
or suspended in a solvent, e.g. such as a mixture of polyester in a
ketone and an alkyl acetate at about 60-80% solids or a mixture of
polyester in alkyl alcohols and alkylene glycol alkyl ethers.
[0011] Alternatively to using a separte polyester and hydroxyl
terminated polymer including repeat units from an oxetane monomer
havin a pendant pendant --CH.sub.2--O--(CH.sub.2).sub.n--Rf one can
react said hydroxyl terminated polymer into the polyester thus
replacing two components with a single component. The hydroxyl
terminated polymer is more completely bound into the network as a
result of prereacting the polyester forming components with the
hydroxyl terminated polymer and is therefore less likely to be
removed from the coating by wear or cleaning. In the claims the
polyester including the including repeat units derived from
copolymerizing said hydroxyl terminated polymer into said polyester
is described as a reactive polyester resin including therein at
least one repeat unit derived from copolymerizing into said
polyester a hydroxyl terminated polymer including repeat units from
an oxetane having a pendant --CH.sub.2--O--(CH.sub.2).sub.n--Rf
group. One skilled in the art would be able to optimize reaction
conditions for forming such a polyester such that the oxetane
repeat units are incorporated into the polyester. Such reaction
conditions may include prereaction of the dibasic acid and the
oxetane polymer having a pendant
--CH.sub.2--O--(CH.sub.2).sub.n--Rf in a separate reaction and then
adding the remaining diacids and polyols to complete the
polymerization of the polyester.
[0012] The amino resin to be reacted with the reactive polyester is
an alkylated benzoguanamine-formaldehyde, an alkylated
urea-formaldehyde or, preferably, an alkylated
melamine-formaldehyde resin. Mixtures of these resins can be used.
The alcohol used to modify the benzoguanamine-formaldehyde,
urea-formaldehyde or melamine-formaldehyde resin can be n-butanol,
n-propanol, isopropanol, ethanol or methanol and so forth. These
amino resins are well known and include those set forth in
"Aminoplastics," Vale et al, Iliffe Books Ltd., London, 1964;
"Amino Resins," Blair, Reinhold Publishing Corporation, New York,
1959, "Modern Plastics Encyclopedia 1980-1981," pages 15, 16 and 25
and "Encyclopedia of Polymer Science And Technology," John Wiley
& Sons, Inc., Vol. 2, 1965, pages 1 to 94.
[0013] Sufficient amounts by weight of the reactive polyester and
amino resin are employed to provide a stain resistant, layer having
good durability and flexibility and having good adhesion to the
substrate. These materials are desirably cured at temperatures of
at least 150, 200, 250 or 400.degree. F. or more (66, 93, 121, or
204.degree. C.) for effective times in the presence of a minor
amount by weight of an acidic catalyst such as boric acid,
phosphoric acid, acid sulfates, hydrochlorides, phthalic anhydride
or acid, oxalic acid or its ammonium salts, sodium or barium ethyl
sulfates, aliphatic or aromatic sulfonic acids such as p-toluene
sulfonic acid (preferred), methane sulfonic acid and the like. It
is important that the stain resistance imparted by the polyester
and amino resin be optimized by controlling things such as glass
transition temperature, crosslink density and the presence of
molecules that may act as plasticizers or other molecules that may
transport or attract staining molecules in the coating. Prior to
curing flatting agents or other additives can be added to the
mixture of the reactive polyester and amino resin.
[0014] The hydroxyl terminated polymer(s) including repeat units
from an oxetane having a pendant
--CH.sub.2--O--(CH.sub.2).sub.n--Rf group are prepared. These can
be prepared according to the teachings of U.S. Pat. Nos. 5,650,483;
5,668,250 and 5,663,289 hereby incorporated by reference for those
teachings. The oxetane monomer desirably has the structure 1
[0015] wherein n is an integer from 1 to 3 and Rf, independently,
on each monomer is a linear on branch alkyl group of 1 to 20 carbon
atoms with a minimum of 25, 50 or 75 percent of the H atoms of said
Rf being replaced by F and optionally up to all of the remaining H
atoms being replaced by I, Cl or Br, or each Rf, independently,
being an oxaperfluorinated polyether having from 4 to 60 carbon
atoms; R being H or an alkyl of 1 to 6 carbon atoms; preferably Rf
has at least 85 and more preferably at least 95% of said H atoms
replaced by F. Preferably said linear or branched alkyl group is of
from 1 or 3 to 7 or 10 carbon atoms.
[0016] The repeat units from said oxetane monomers desirably have
the structure 2
[0017] where n, Rf, and R are as described above.
[0018] The hydroxyl terminated polymer(s) including repeat units
from said oxetane monomers can have one or more terminal hydroxyl
groups. They desirably have number average molecular weights from
about 250, 500, 1,000 or 5,000 to about 50,000 or 100,000. The
polymer(s) can be a homopolymer or a copolymer of two or more
different oxetane monomers. The polymer may also be a copolymer of
cyclic ether molecules having from 2 to 4 carbon atomos in the ring
such as tetrahydrofuran and one or more oxetane monomers as
described in the previously incorporated U.S. Pat. No. 5,668,250.
The copolymer may also include copolymerizable substituted cyclic
ethers such as substituted tetrahydrofurans. The repeat unit from a
tetrahydrofuran monomer has the formula to
--(O--CH.sub.2--CH.sub.2--CH- .sub.2--CH.sub.2--). The hydroxyl
terminated polymer optionally includes a cyclic tetramer of said
oxetane monomer which may be a byproduct of the polymerization. In
some embodiments, said hydroxyl terminated polymer includes up to
10, 20 or 30 wt % of said tetramer based on the weight of said
hydroxyl terminated polymer(s).
[0019] It is desirable that the polymer including repeat units from
an oxetane having a pendant --CH.sub.2--O--(CH.sub.2).sub.n--Rf
group has one or more hydroxyl groups in that this provides a
possible mechanism for this polymer to be chemically bound into the
polyester-amino resin composition. It is acknowledged that the
amount of such bound polymer has not been measured in the examples
and it may be a small or large percentage of the total polymer with
said oxetane repeat units. In some embodiments it may be desirable
to prereact the hydroxyl terminated polymer with the polyester
component to increase the percentage of hydroxyl polymer bound into
the coating. It is also acknowledged that the percentage of the
polymer with said oxetane repeat units and the oxetane repeat units
themselves may not be uniformly distributed through the bulk of the
coating. Said oxetane repeat units may be disproportionately
present at the surface of the coating due to the low surface
tension of those repeat units.
[0020] The amount of the various components in the coating will be
generally specified in relationship to 100 parts by weight of the
polyester resin and the amino resin crosslinking agent. The weight
ratio of polyester resin (neat) to amino resin (neat) can vary
widely but desirably is from about 10:90 to 90:10 and more
desirably from about 20:80 to 80:20. Generally it is more desirable
to match the moles of reactive groups on the polyester to within 10
to 20% to the number of moles of reactive groups on the amino
resin. The number of moles of reactive groups can be determined by
dividing the weight of the component by the equivalent weight for
the component. The term "neat" after polyester and amino resin does
not exclude using polyesters and amino resins that are received
dissolved in solvents but rather specifies that the amount used is
to be recalculated based on the weight without the solvent. For the
purposes of this disclosure no distinction will be made whether the
amino resin crosslinks the polyester resin or vice versa.
[0021] The amount of carriers and/or solvent(s) in the coating
composition can vary widely depending on the coating viscosity
desired for application purposes, and solubility of the components
in the solvent. The solvent(s) can be any conventional solvent for
polyester-amino resin systems. These carriers and/or solvents
include but are not limited to water, alkyl alcohols of 1 to 10
carbon atoms, ketones of from 3 to 15 carbon atoms e.g. methyl
ethyl ketone or methyl isobutyl ketone, alkylene glycols and/or
alkylene glycol alkyl ethers having from 3 to 20 carbon atoms,
acetates and their derivatives, ethylene carbonate, etc.
Illustrative U.S. patents of the carrier and/or solvent systems
available include U.S. Pat. Nos. 4,603,074; 4,478,907; 4,888,381
and 5,374,691 hereby incorporated by reference for their teachings
both of carriers and/or solvent systems and of polyesters and amino
resins. The amount of solvent(s) can desirably vary from about 20
parts by weight to about 400 parts by weight per 100 parts by
weight of total polyester resin and amino resin.
[0022] The amount of the oxetane repeat units having a pendant
CH.sub.2--O--(CH.sub.2).sub.nRf group is desirably from about 0.1
or 0.2 to about 10 or 15 parts by weight and more desirably from
about 0.5 to about 10 or 15 parts by weight per 100 parts total
weight of said polyester resin and amino resin. Of course if the
hydroxyl terminated polymer(s) including repeat units from said
oxetane has a significant amount of repeat units from
tetrahydrofuran or other repeating unit therein, the hydroxyl
terminated polymer's weight will exceed that of said oxetane repeat
units.
[0023] The amount of catalyst is an amount that effectively
catalyzes the mutual crosslinking of the polyester and amino resins
under the crosslinking conditions chosen (usually elevated
temperatures). As the crosslinking temperature increases above 150,
200, 250 or 400.degree. F. (66, 93, 121 or 204.degree. C.) the
amount of catalyst can be reduced. Effective amounts of catalyst
can vary from about 0.1, 0.5 or 1 to about 6 or 8 parts by weight
and preferably from about 2 or 3 to about 6 parts by weight per 100
parts by weight total of said polyester and amino resins.
[0024] Conventional flattening agents can be used in the coating
composition in conventional amounts to control the gloss of the
coating surface to an acceptable value. Examples of conventional
flattening agents include the various waxes silicas, aluminum
oxide, alpha silica carbide, etc. Amounts desirably vary from about
0 to 0.1 to about 5 or 10 parts by weight per 100 parts by weight
total of said polyester and amino resins. For most embodiments high
gloss is preferred.
[0025] Additionally other conventional additives for polyester and
amino resin compositions or for other clear coating applications in
general can be used in the composition. Examples include viscosity
modifiers, antioxidants, antiozonants, processing aids, pigments,
fillers, ultraviolet light absorbers, adhesion promoters,
emulsifiers, dispersants, etc.
[0026] While this disclosure generally teaches applying the
dry-erase coating directly to a substrate, it also provides for
intermediate coating(s) between the substrate and the dry erase
coating. These intermediate coating(s) can be decorative coatings
to provide a colored background or a printed (patterned)
background. Alternatively or additionally they can be a buffer
between the substrate and the dry-erase coating preventing
interaction between the dry-erase coating and the substrate. Or
they can prevent interaction between components in the substrate
and components in the dry-erase coating (e.g. keeping plasticizer
from the substrate from migrating into the coating). An
intermediate coating(s) may also function to improve adhesion of
the dry erase coating to the substrate when adhesion is a concern.
An example where adhesion might be improved is with a polyolefin
(polyethylene or polypropylene) substrate which may be plasma or
corona surface treated or have a hydrocarbon intermediate adhesive
layer applied thereto before the dry-erase coating is applied.
[0027] The substrates may be any material which would benefit from
a stain resistance or dry-erase coating. Examples include
cellulosic products (coated and uncoated paper, boardstock,
cardboard, wood and paneling), fibers, synthetic polymers
(including polyolefins, polyesters, polycarbonates, polystyrene,
poly (methacrylates) and especially highly filled or highly
plasticized ones which are more porous towards stains e.g.
polyvinyl chloride), metals (requiring temporary or permanent
protection from stains), and ceramics.
[0028] The coating composition can be prepared by a variety of
mixing techniques. Most of the components can be prediluted or
pre-combined with other components. When the catalyst, polyester
resin, and amino resin are combined they can begin to crosslink. A
convenient formulation procedure is to combine the polyester resin,
solvent(s), amino resin, and any non catalyst additives in one
container. In a separate container the catalyst and optionally
solvent can be stored. Shortly before application the catalyst can
be combined and mixed with the other components.
[0029] The substrate with stain resistant layers of the present
invention are particularly useful as dry erase writing surfaces
(including boards, posters, papers, clipboards, menus, etc.)
wallcoverings, anti graffiti surfaces e.g. in public areas
including restrooms, and in kitchens and food preparation areas.
However, these stain resistant laminates, also, can be used in the
manufacture of tablecloths, shoe uppers, luggage exteriors,
upholstery, vehicle interiors and seats, golf bags and other
sporting goods and so forth.
[0030] The polyvinyl chloride can be an emulsion (plastisol grade)
or a suspension grade vinyl chloride polymer. The vinyl chloride
polymer can be polyvinyl chloride homopolymer (preferred) or a
copolymer of a major amount by weight of repeat units from vinyl
chloride and a minor amount by weight from a copolymerizable
monomer selected from the group consisting of vinyl acetate,
vinylidene chloride and maleic ester. Bulk and solution vinyl
chloride polymers, also may be used. Mixtures of vinyl chloride
polymers can be used. Vinyl chloride polymers and copolymers are
well known and include those set forth in "Vinyl and Related
Polymers," Schildknecht, John Wiley & Sons, Inc., New York,
1952; Sarvetnick, "Polyvinyl Chloride," Van Nostrand Reinhold
Company, New York 1969; Sarvetnick, "Plastisols and Organosols,"
Van Nostrand Reinhold Company, New York, 1972 and "Modern Plastics
Encyclopedia 1980-1981," October, 1980, Volume 57, No. 10A,
McGraw-Hill Inc., New York.
[0031] The amount of plasticizer used to plasticize the vinyl
chloride polymer to make it flexible may vary from about 20 or 30
to about 100 parts by weight per 100 parts by weight of total vinyl
chloride polymer resin more desirably from about 20 or 30 to about
50 or 60 parts by weight for wallpaper applications and from about
60 to about 100 parts by weight for upholstery type applications
per 100 parts by weight of total polyvinyl chloride. Any
conventional plasticizer for PVC can be used. Examples of
plasticizers which may be used are butyl octyl phthalate, dioctyl
phthalate, hexyl decyl phthalate, dihexyl phthalate, diisooctyl
phthalate, dicapryl adipate, dioctyl sebacate, trioctyl
trimellitate, triisooctyl trimellitate, triisononyl trimellitate,
isodecyl diphenyl phosphate, tricresyl phosphate, cresyl diphenyl
phosphate, polymeric plasticizers, epoxidized soybean oil, octyl
epoxy tallate, isooctyl epoxy tallate and so forth. Mixtures of
plasticizers may be used.
[0032] Other vinyl chloride polymer compounding ingredients are
desirably incorporated in the vinyl chloride polymer compositions.
Examples of such ingredients are the silicas such as precipitated
silica, fumed colloidal silica, calcium silicate and the like,
calcium carbonate, ultra violet light absorbers, fungicides, carbon
black, barytes, barium-cadmium-zinc stabilizers, barium-cadmium
stabilizers, tin stabilizers, dibasic lead phosphite,
Sb.sub.2O.sub.3, zinc borate, molybdates such as ammonium
octa-molybdates, aluminum oxide, aluminum trihydrate and so forth
and mixtures of the same. TiO.sub.2, red iron oxide, phthalocyanine
blue or green or other color pigments can be used. The pigments and
the other dry additives preferably are dispersed or dissolved in
one or more plasticizers before adding to the plasticized vinyl
chloride polymer compositions. These compounding ingredients are
used in effective amounts by weight to control color, mildew,
stabilization to ultra-violet light and heat, viscosity and so
forth of the plasticized vinyl chloride polymer.
[0033] The vinyl chloride polymer composition may contain suitable
blowing or foaming agents such as sodium bicarbonate, and the
organic agents like 1,1-azobisformamide, 4,4-oxybis (benzene
sulfonyl-hydrazide), p-toluenesulfonyl hydrazide, or water and so
forth to form a cellular or foamed vinyl chloride polymer
composition layer or sheet on fusing. The blowing agents may
require an activator. Such blowing agents are well known.
[0034] Vinyl chloride polymer blending or extender resins, also,
can be used in the compositions in a minor amount by weight as
compared to the vinyl chloride polymer composition.
[0035] The ingredients forming the vinyl chloride polymer
composition may be charged to and mixed together in any one of
several mixing devices such as a Ross Planetary mixer, Hobart dough
type mixer, Banbury, 2-roll rubber mill, Nauta mixer and ribbon
blender and so forth.
[0036] The vinyl chloride polymer composition can be formed into
layers of films which can be unsupported or supported (preferred).
Where a vinyl chloride polymer plastisol composition is used, it
may be cast on a release surface and heated to fuse it to form a
film. Where a plasticized suspension grade vinyl chloride polymer
composition is used, it can be calendered or extruded and fused to
form a film. Temperatures may vary from about 200 to about
400.degree. F. (93-204.degree. C.). However, it is preferred that
in either case the compounded vinyl chloride polymer compositions
be supported or have a backing. In the case of the supported vinyl
chloride polymer composition, the substrate can be a woven fabric
(drill, scrim, cheesecloth, and so forth), a knit fabric, a
non-woven fabric, paper etc. The fabric can be continuous,
discontinuous, woven, nonwoven, bundled etc and made of cotton,
cellulose, nylon, polyester, aramid, glass, rayon or acrylic fibers
or cords or mixtures of the same. It may be necessary in some
instances to treat the fabric with an adhesive coating or dip to
adhere or to improve adhesion of the fabric to the vinyl chloride
polymer composition.
[0037] The vinyl chloride polymer composition film or layer,
supported or unsupported, is preferably printed on the surface with
a suitable vinyl chloride polymer receptive ink to form desirable
and novel pattern and/or design. Such inks are well known and can
be applied by various methods of printing such as by gravure,
flexography, screen printing, jet printing, web printing,
non-impact printing and so forth as for example, set forth in
"Modern Plastics Encyclopedia 1980-1981," pages 464-465. The
printing operation may be repeated for up to five times or more to
vary the colors and designs at temperatures of desirably from about
150 to about 165.degree. F. (66-74.degree. C.) for each printing
step.
[0038] The vinyl chloride polymer composition film or layer,
supported or unsupported, printed or unprinted, is preferably
embossed to texture the vinyl chloride layer to provide a pattern
or design for esthetic or functional purposes. Embossing of
thermoplastic films, layers or sheets is well known and is usually
carried out by passing the film between an embossing roll and a
backup roll under controlled pre-heating and post-cooling
conditions. See "Modern Plastics Encyclopedia 1980-1981," pages
454-45. Additional decorating or printing can sometimes be done
with the above stated inks over the embossed vinyl chloride polymer
surface for better aesthetic purposes.
[0039] The following examples will serve to illustrate the present
invention with more particularity to those skilled in the art.
[0040] Preparation of Poly-Fox Materials (U.S. Pat. No.
5,650,483)
[0041] A 10 L jacketed reaction vessel with a condenser,
thermo-couple probe, and a mechanical stirrer was charged with
anhydrous methylene chloride (2.8 L), and 1,4-butanediol (101.5 g,
1.13 moles). BF.sub.3THF (47.96 g, 0.343 moles) was then added, and
the mixture was stirred for 10 minutes. A solution of 3-Fox (3,896
g. 21.17 moles) in anhydrous methylene chloride (1.5 L) was then
pumped into the vessel over 5 hours. The reaction temperature was
maintained between 38 and 42.degree. C. throughout the addition.
The mixture was then stirred at reflux for an additional 2 hours,
after which 'H NMR indicated >98% conversion. The reaction was
quenched with 10% aqueous sodium bicarbonate (1 L), and the organic
phase was washed with 3% aq. HCl (4 L) and with water (4 L). The
organic phase was dried over sodium sulfate, filtered, and stripped
of solvent under reduced pressure to give 3,646 g (91.2%) of title
glycol, a clear oil. NMR: The degree of polymerization (DP) as
determined by TFAA analysis was 15.2 which translates to an
equivalent weight of 2804. The THF content of this glycol, as
determined by 1 H NMR, was 2.5% wt THF (6.2% mole THF). This was
used in Examples 1 and II.
EXAMPLE I
Coating Composition
[0042] Melamine resin (Resimene 747, 25.92 g) and polyester resin
(Vr-248, Texas Resin, 74.78g) were mixed with variable amounts of a
Poly-FOX-3 polymer available from Aerojet in Sacramento, Calif.
Isopropyl acetate 82.00 g and tetrahydrofuran (THF) 8.30 g were
added to reduce the viscosity. A small amount of p-toluene sulfonic
acid 39.6 g (10% solution in isopropanol) was added and the
solution was mixed under shear for 5 minutes. Poly-Fox-3 polymer is
a hydroxyl terminated polymer including repeat units from an
oxetane monomer having a pendant --CH.sub.2--O--(CH.sub.2).sub.nRF
group where Rf is CF.sub.3.
EXAMPLE II
[0043] A smooth PVC film was coated with a solvent borne
PVC/acrylate primer. A portion of the primed substrate was coated
with the composition of Example I which had no Poly-FOX-3 (Example
II Control) and a portion of the substrate was coated with the
composition of Example I which had 2 parts by weight of Poly-FOX-3
per 100 parts by weight total of said polyester and melamine
resins, (Example IIA). The coatings on Example II Control and
Example IIA were cured at 200.degree. F. (93.degree. C.).
Commercial dry erase markers were used to mark both examples. The
resulting marks were easily removed with a dry cloth or eraser from
Example IIA. The Example II Control erased partially but left
severe shadowing using a dry eraser.
[0044] While in accordance with the patent statutes the best mode
and preferred embodiment have been set forth, the scope of the
invention is not limited thereto, but rather by the scope of the
attached claims.
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