U.S. patent application number 13/583252 was filed with the patent office on 2013-02-14 for heat-curable powder coating compositions, which after the coating has cured result in a matt surface and simple method for producing same.
This patent application is currently assigned to Evonik Degussa GmbH. The applicant listed for this patent is Klaus Behrendt, Werner Grenda, Christoph Lammers, Holger Loesch, Emmanouil Spyrou, Thomas Weihrauch. Invention is credited to Klaus Behrendt, Werner Grenda, Christoph Lammers, Holger Loesch, Emmanouil Spyrou, Thomas Weihrauch.
Application Number | 20130041103 13/583252 |
Document ID | / |
Family ID | 44508086 |
Filed Date | 2013-02-14 |
United States Patent
Application |
20130041103 |
Kind Code |
A1 |
Grenda; Werner ; et
al. |
February 14, 2013 |
HEAT-CURABLE POWDER COATING COMPOSITIONS, WHICH AFTER THE COATING
HAS CURED RESULT IN A MATT SURFACE AND SIMPLE METHOD FOR PRODUCING
SAME
Abstract
The invention relates to heat-curable powder coating
compositions, which after the coating has cured result in a matt
surface and to a simple method for producing same
Inventors: |
Grenda; Werner; (Herne,
DE) ; Spyrou; Emmanouil; (Schermbeck, DE) ;
Weihrauch; Thomas; (Duelmen, DE) ; Lammers;
Christoph; (Recklinghausen, DE) ; Loesch; Holger;
(Herne, DE) ; Behrendt; Klaus; (Haltern am See,
DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Grenda; Werner
Spyrou; Emmanouil
Weihrauch; Thomas
Lammers; Christoph
Loesch; Holger
Behrendt; Klaus |
Herne
Schermbeck
Duelmen
Recklinghausen
Herne
Haltern am See |
|
DE
DE
DE
DE
DE
DE |
|
|
Assignee: |
Evonik Degussa GmbH
Essen
DE
|
Family ID: |
44508086 |
Appl. No.: |
13/583252 |
Filed: |
March 10, 2011 |
PCT Filed: |
March 10, 2011 |
PCT NO: |
PCT/EP2011/053639 |
371 Date: |
September 10, 2012 |
Current U.S.
Class: |
524/606 |
Current CPC
Class: |
C09D 163/00 20130101;
C08G 59/4246 20130101; C09D 133/00 20130101; C08G 59/46 20130101;
C08L 63/00 20130101; C09D 167/00 20130101; C09D 5/032 20130101;
C09D 133/08 20130101; Y10T 428/3179 20150401; C08K 5/20
20130101 |
Class at
Publication: |
524/606 |
International
Class: |
C09D 167/00 20060101
C09D167/00 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 11, 2010 |
DE |
10 2010 002 785.5 |
Claims
1. A powder coating composition, comprising: A) a polymer
comprising a carboxylate group and having an acid number of 5 to
250 mg KOH/g and a glass transition temperature T.sub.g of greater
than 40.degree. C.; and B) a .beta.-hydroxyalkylamide having two or
three or four .beta.-hydroxyalkylamide groups per molecule of the
formula I ##STR00024## wherein: R.sup.1 and R.sup.2 are,
independently of one another, identical or different radicals
selected from the group consisting of an alkyl radical, a
cycloalkyl radical, an aryl radical, an aralkyl radical and an
alkenyl radical having 1-24 carbon atoms, said radicals optionally
comprising a heteroatom, a functional group, or both, and where
R.sup.1 may also be hydrogen, such that R.sup.2 is optionally:
##STR00025## A is A.sup.1, A.sup.2 or A.sup.3: ##STR00026## such
that radicals R.sup.3 are, independently of one another, identical
or different radicals selected from the group consisting of
hydrogen, an alkyl radical, a cycloalkyl radical, an aryl radical,
an aralkyl radical and an alkenyl radical having 1-24 carbon atoms,
said radicals optionally comprising a heteroatom, a functional
group, or both, such that two or more substituents R.sup.3 are
optionally linked with one another to form rings; and the
.beta.-hydroxyalkylamide is present in solid form below 150.degree.
C.; C) optionally auxiliaries additives, or both; wherein a ratio
of the .beta.-hydroxyalkylamide groups to the carboxylate groups is
between 0.5:1 to 1.5:1.
2. The powder coating composition of claim 1, wherein the
.beta.-hydroxyalkylamide derives from .beta.-hydroxyalkylamines
comprising alkyl groups having at least 2 to 10 carbon atoms in the
hydrocarbon framework as starting materials, said alkyl groups
being linear, branched or cyclic and optionally substituted by at
least one heteroatom, and optionally comprising at least one
functional group such that the .beta.-hydroxyalkylamines optionally
comprise an additional alkyl radical on the nitrogen.
3. The powder coating composition of claim 1, comprising
.beta.-hydroxyalkylamides of N-alkyl-1,2-alkanolamines and/or of
N,N-bis-2-hydroxyalkylamines and esters of cyclohexanedicarboxylic
acids.
4. The powder coating composition of claim 1, wherein the
.beta.-hydroxyalkylamines are hydroxylamines of the formulae II
and/or III: ##STR00027## wherein R.sup.1 is hydrogen, methyl,
ethyl, or propyl, R.sup.2 is methyl; ##STR00028## wherein radicals
R.sup.1 simultaneously or independently of one another are
hydrogen, methyl, ethyl, or propyl.
5. The powder coating composition of claim 1, wherein the following
compounds are starting materials for preparing the
.beta.-hydroxyalkylamide: diethanolamine (DEA),
di-isopropropanolamine (DIPA), di-sec-butanolamine,
N-methylethanolamine, N-methylisopropanolamine.
6. The powder coating composition of claim 1, wherein the
substituent A derives from 1,2-substituted, 1,3-substituted, and
1-4-substituted cyclohexanedicarboxylic acid derivatives.
7. The powder coating composition of claim 1, wherein the
.beta.-hydroxyalkylamide is prepared from compounds of the formula
IV: ##STR00029## wherein radicals R.sup.4 simultaneously or
independently of one another are methyl, ethyl, propyl, or
butyl.
8. The powder coating composition of claim 1, wherein at least one
1,4-substituted cyclohexanedicarboxylic ester is a starting
compound.
9. The powder coating composition of claim 1, wherein the
.beta.-hydroxyalkylamide B) has at least one of the following
formulae: ##STR00030## wherein: R.sup.2 is methyl, or ##STR00031##
where R.sup.1A is hydrogen and R.sup.1B is methyl, ethyl, or
propyl, or R.sup.1A is methyl, ethyl, or propyl and R.sup.1B is
hydrogen; A is a 1,4-disubstituted cyclohexane ring of the formula:
##STR00032## a trans content of A is .gtoreq.70 mol %; and at least
one .beta.-hydroxyalkylamide B) is present in solid form below
150.degree. C.
10. The powder coating composition of claim 1, comprising
.beta.-hydroxyalkylamides of dialkyl 1,4-cyclohexyldicarboxylates,
with a trans content, based on the position of the carboxyl groups
on the cyclohexyl ring, of greater than or equal to 70 mol %.
11. The powder coating composition of claim 1, wherein: the
.beta.-hydroxyalkylamide consists of dimethyl
1,4-cyclohexyldicarboxylate and diethanolamine having four
.beta.-hydroxyalkylamide groups per molecule of the formula XII:
##STR00033## having a trans content on the cyclohexyl ring of
greater than or equal to 70 mol.
12. The powder coating composition of claim 1, wherein the
.beta.-hydroxyalkylamide is present in solid form below 150.degree.
C.
13. The powder coating composition of claim 1, comprising a
polyester A) comprising at least one carboxylate group and having:
a glass transition temperature T.sub.g in a range from 40 to
80.degree. C. an acid number varied from 5-250 mg KOH/g; an OH
number of less than 15 mg KOH/g; and an average molecular weight
M.sub.w of 1000 to 10 000 g/mol.
14. The powder coating composition of claim 1, comprising an
acrylate polymer A) comprising at least one carboxylate group and
having: an OH number of less than 10 mg KOH/g; an acid number of 10
to 350 mg KOH/g; a Tg of 40 to 110.degree. C.; and an M.sub.W of
500 to 50 000 g/mol.
15. The powder coating composition of claim 1, comprising at least
one co-crosslinker based on epoxy resins and/or
.beta.-hydroxyalkylamides different from the
.beta.-hydroxyalkylamide B).
16. A method for producing the powder coating composition of claim
1, the method comprising conducting joint extrusion of all the
components in a melt at temperatures between 80 to 150.degree.
C.
17. A process for producing a coating for a matt surface, the
process comprising applying the powder coating composition of claim
1 to a surface, wherein the coating has a gloss to DIN 67530/ISO
2813 of <50 at an incident angle of 60.
18. The powder coating composition of claim 1, comprising a
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according
to the formula XIIA as component B), ##STR00034## having the
following parameters: a trans content on the cyclohexyl ring of the
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide of greater
than or equal to 70 mol %, based on the total amount of all of the
isomers of N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide
that are present; two endothermic peaks according to DSC analysis
(differential scanning calorimetry), where peak 1 is situated in
the region of 140-170.degree. C. with a maximum of 155-165.degree.
C., and peak 2 is situated in the region of 170-210.degree. C. with
a maximum of 175-207.degree. C.; a ratio of the enthalpies of the
peak 1 to the peak 2 is 1:1 to 1:5; and the following peaks in the
XRPD spectrum of the powder sample in the x-ray diffractometer,
measured with Cu K.alpha. radiation (1.541 .ANG.): TABLE-US-00024
Degrees 2theta .+-. Peak #. 0.2 degree 2theta d (.ANG.) 1 14.90
5.94 2 16.70 5.31 3 17.40 5.09 4 21.20 4.19 5 21.60 4.11 6 26.00
3.43.
19. The powder coating composition of claim 18, having a trans
content on the cyclohexyl ring of greater than or equal to 92 mol
%, based on the total amount of all of the isomers of
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide that are
present.
20. The powder coating composition of claim 18, wherein the
.beta.-hydroxyalkylamide of the formula XIIA is present in solid
form below 175.degree. C.
21. The powder coating composition of claim 18, wherein a
concentration of all of the isomers of
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide in the end
product after its production is 75% by mass.
22. The powder coating composition of claim 18, wherein a ratio of
the enthalpies of the peak 1 to the peak 2 is 1:1 to 1:3.
23. The powder coating composition of claim 18, wherein the
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide, according
to x-ray structural analysis of a single crystal, has the following
parameters: TABLE-US-00025 Crystal system: Orthorhombic Space
group: Pbca Unit cell dimensions: a = 10.06350(10) .ANG. .alpha. =
90.degree.[[.]] b = 11.85290(10) .ANG. .beta. = 90.degree.[[.]] c =
14.6275(2) .ANG. .gamma. = 90.degree.[[.]] Volume: 1744.79(3)
.ANG..sup.3.
24. A process for producing a coating for a matt surface, the
process comprising applying the powder coating composition of claim
18 to a surface, wherein the coating has matt surfaces with <50
gloss units, measured as reflectometer values to DIN 67530/ISO 2813
with an incident angle of 60.degree..
25. The process of claim 24, wherein the
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide, according
to x-ray structural analysis of a single crystal, has the following
parameters: TABLE-US-00026 Crystal system: Orthorhombic Space
group: Pbca Unit cell dimensions: a = 10.06350(10) .ANG. .alpha. =
90.degree.. b = 11.85290(10) .ANG. .beta. = 90.degree.. c =
14.6275(2) .ANG. .gamma. = 90.degree.. Volume: 1744.79(3)
.ANG..sup.3.
26-27. (canceled)
Description
[0001] The invention relates to thermosetting powder coating
compositions which have a matt surface after the coating is cured,
and also to a simple method for their production.
[0002] Heat-curable powder coating materials do not emit any
organic solvents on application, and therefore clearly possess
environmental advantages over liquid paints. Crosslinking under hot
conditions takes place via polyaddition reactions or
polycondensation reactions between the functional groups present in
the binders. Typical binder systems are epoxy resins with curing
agents based on amines, amidines, acids, anhydrides; carboxyl
polyesters or polyacrylates with curing agents based on epoxides;
hydroxyl polyesters or polyacrylates with crosslinkers based on
blocked isocyanates; polyacrylates containing epoxide groups with
dicarboxylic acids as crosslinkers, carboxyl polyesters or
polyacrylates with crosslinkers based on .beta.-hydroxyalkylamides,
etc. As well as the technical coatings properties, the various
binder systems differ particularly in the stability to outdoor
weathering. The pure binder systems lead in general to highly
glossy surfaces, with a gloss of >80 scale divisions (DIN
67530/ISO 2813, incident angle 60.degree.), when they are processed
in a one-shot process with only one co-reactant, e.g., crosslinker
and resin, and are induced to cure.
[0003] There is considerable interest in coating systems which
endow a substrate with a uniformly even and matt surface. The
reason for this is primarily practical. Glossy surfaces require a
far higher degree of cleaning than do matt surfaces. Furthermore,
it may be desirable on safety grounds to avoid highly reflecting
surfaces. In wide areas of application in the powder coatings
industry, such as architectural, automotive, and metal-furnishing
segments, etc., there is a rise in demand in matt (10-30 units) and
semimatt (30-50 units) surfaces, measured as reflectometer values
to DIN 67530/ISO 2813 at an incident angle of 60.degree..
[0004] The most simple principle for obtaining a matt surface is to
admix the powder coating material with smaller or greater
amounts--depending on the extent of the desired matt effect--of
fillers, such as chalk, finely divided silicon dioxide or barium
sulfate, for example. These additions, though, produce a
deterioration in the technical coatings film properties, such as
adhesion, flexibility, impact strength, and chemicals
resistance.
[0005] Although the addition of substances incompatible with the
coating material, such as waxes or cellulose derivatives, for
example, does produce a distinct matting, slight changes during
extrusion lead to fluctuations in the surface gloss and to a
"fade-out" effect in dark shades. The reproducibility of the matt
effect is not guaranteed. EP 0698645 describes the production of
matt powder coatings by dry-blending of at least two separately
produced hydroxylalkylamide powder coating materials. U.S. Pat. No.
3,842,035 therefore proposes producing matt powder coatings by
dry-blending ready-made powder coating materials having
sufficiently different reactivities, i.e., powder coating materials
having very short and very long gelling times. The binders used are
acrylic resins, alkyd resins, and--preferably--epoxy resins.
WO-A-89/06674 describes the production of satin-gloss or matt
surfaces by dry blending, in other words physical blends of
ready-made powder coating materials, which are composed of
different binder systems.
[0006] DE 2 324 696 proposes a method for producing matt coatings
by using a specialty curing agent reacting with epoxide groups--the
salt of cyclic amidines with certain polycarboxylic acids.
According to this method, the powder coating material undergoes
crosslinking with different reactivity at different temperatures,
thus forming, on the surface, microstructures which exhibit a matt
surface. The application of this method, however, is confined to
epoxide and carboxyl polyester/epoxide powder coating materials,
meaning that this method cannot be used to produce coatings with
sufficient weathering stability.
[0007] EP 366 608 likewise proposes a method for producing powder
coatings having matt surfaces. It relates to powder coating
materials based on epoxy resins or epoxide compounds, such as
triglycidyl isocyanurate (TGIC), for example, with
carboxyl-terminated polyester resins and mixtures of di-, tri- or
tetrakis(.beta.-carboxyethyl)cyclohexanones or -cyclopentanones.
The matt effect here is attributed to the difference in reactivity
between the aliphatic carboxylate groups of the crosslinker and the
aromatic carboxylate groups of the carboxyl-terminated polyester
resin.
[0008] Another patent specification, DE 3 232 463, describes powder
coatings with matt surfaces by joint extrusion of
hydroxyl-terminated polyester resins, epoxide compounds, such as
TGIC, for example, and special, reversibly blocked polyisocyanates
having free carboxylate groups.
[0009] U.S. Pat. No. 4,801,680 (EP 322 834) describes a
heat-curable powder coating material which consists of a
particulate mixture comprising a polyester containing carboxylate
groups and a .beta.-hydroxyalkylamide. Following application to a
substrate, this powder coating material leads to glossy film
surfaces. According to example 2 of U.S. Pat. No. 4,801,680, the
resulting film surfaces exhibit no film-surface deterioration after
an accelerated weathering test has been carried out and using UV
irradiation EP 520429 describes a resin composition comprising
polyesters having different hydroxyl numbers. The resin composition
described necessarily comprises a substantially ungelled polyester
A, a substantially ungelled polyester B,
tetramethoxymethylglycoluril as curing agent, and an organic
sulfonic acid as catalyst.
[0010] Numerous further publications have appeared concerning the
possibilities for matting hydroxyalkylamide powder coatings,
examples being R. Franiau, "Advances in .beta.-Hydroxyalkylamide
crosslinking chemistry" ECJ, (2002) 10, p 409ff; D. Fink, U.
Kubilius, "Optimising the Matting of Powder Coatings", Powder
Coatings Europe 2002, and R. Guida, "A Novel Approach to Produce
Reduced Gloss .beta.-Hydroxyl Alkylamide Powder Coatings" Powder
Coating 2002 PCI Conference; D. Beccaria et al. "Modeling Gloss
Control in Polyester/.beta.-Hydroxyalkylamide Powder Coatings Based
on SPM Structure-Property Relationship", Waterborne, High-Solids
and Powder Coatings Symposium, Feb. 26-28, 2003, New Orleans, La.,
USA.
[0011] Laid-open specification KR 10-2009-0111720 (application
number 10-2008-0037454), with translated title "CYCLOALKANE
DICARBOXAMIDE COMPOUNDS, THEIR PREPARATION AND APPLICATION" (see
also J. Korean Ind. Eng. Chem., vol. 20, No. 2, April 2009,
195-200), discloses in particular in example 1 the therein-named
compound
N.sup.1,N.sup.1,N.sup.4,N.sup.4-tetrakis(2-hydroxyethyl)cyclohexane-1,4-d-
icarboxamide (formula 3). This compound according to FIG. 2 has
only one peak according to DSC analysis, with a maximum peak at
approximately 190.degree. C. A cis/trans content for the compound
is not stated. Furthermore, polyesters containing carboxyl groups,
which are not precisely defined but instead are indicated only by
broad ranges of certain parameters (polyesters not unambiguously
characterized and unknown on the market with this viscosity), are
crosslinked with this compound and compared with the known
.beta.-hydroxyalkylamide, in this case named in example 3 as
[N.sup.1,N.sup.1,N.sup.6,N.sup.6-tetrakis(2-hydroxyethyl)adipamide]
(available as VESTAGON HAA 320 or PRIMID XL 552), in other words
with curing agents from the prior art, and with long-established
market products, which are known to lead to glossy surfaces on the
coatings produced. In FIGS. 3 and 4, the metal panels are shown.
There is no description to the effect that the coatings in question
are matt. Nor is this possible, since the coatings obtained with
the conventional curing agents are glossy.
[0012] Therefore, for matt and semimatt (<50 gloss units) powder
coating compositions with hydroxylalkylamides, state of the art is
what are called dry blends; in other words, the separate
preparation of two hydroxyalkylamide powder coating materials is
required, based on .beta.-hydroxyalkylamides, plus resins
(polymers) with different acid numbers, which are then supplied in
the form of a dry blend to the grinding operation. This involves
considerable extra cost and effort and, in the event of deviation
in a binder component, results in gloss deviations which take
considerable extra cost and effort to correct. Furthermore, these
dry blends undergo separation, including at the premises of the end
customer, with a resultant shift in gloss if the powder coating, as
is usual, is to be recycled.
[0013] It was an object of the invention to find thermosetting
powder coating composition which after the coating is cured exhibit
a matt surface, and also a simple method for their production.
[0014] This object is achieved by the new .beta.-hydroxyalkylamides
of the invention as crosslinkers (curing agents), and also by the
method of the invention.
[0015] The invention provides a powder coating composition
substantially comprising [0016] A) at least one polymer containing
carboxylate groups and having an acid number of 5 to 350 mg KOH/g
and a glass transition temperature T.sub.g of greater than
40.degree. C., [0017] and [0018] B) at least one
.beta.-hydroxyalkylamide having two or three or four
.beta.-hydroxyalkylamide groups per molecule of the formula I
[0018] ##STR00001## where R.sup.1 and R.sup.2 are, independently of
one another, identical or different radicals selected from alkyl
radical, cycloalkyl radical, aryl radical, aralkyl radical or
alkenyl radical having 1-24 carbon atoms, it being possible for the
radicals also to contain heteroatoms and/or functional groups, and
where R.sup.1 may also be hydrogen, and where R.sup.2 may also
be
##STR00002## and A is
##STR00003## where radicals R.sup.3 are, independently of one
another, identical or different radicals selected from hydrogen,
alkyl radical, cycloalkyl radical, aryl radical, aralkyl radical or
alkenyl radical having 1-24 carbon atoms, it being possible for the
radicals also to contain heteroatoms and/or functional groups, and
where two or more substituents R.sup.3 may be linked with one
another to form rings; where the .beta.-hydroxyalkylamides are
present in solid form below 150.degree. C.; [0019] C) optionally
auxiliaries and/or additives; where the ratio of
.beta.-hydroxyalkylamide groups to the carboxylate groups is
between 0.5:1 to 1.5:1.
[0020] Surprisingly it has been found that through the use of the
new .beta.-hydroxyalkylamides of formula I of the invention as
crosslinkers it is possible to obtain coatings having matt (10-30
units) and semimatt (30-50 units) surfaces, measured as
reflectometer values to DIN 67530/ISO 2813 at an incident angle of
60.degree..
[0021] Surprisingly it has been found that through the method of
the invention, in a one-shot operation, in other words by joint
extrusion of all of the components, it is possible to obtain the
powder coating composition of the invention, based on polymers
containing carboxylate groups and .beta.-hydroxyalkylamides of the
invention as crosslinkers.
[0022] In the context of this invention the terms crosslinker and
curing agent are used synonymously.
[0023] There is no requirement for costly and involved dry blending
of at least two powder coating materials which differ in
reactivity, on the basis of .beta.-hydroxyalkylamides as
crosslinkers. Furthermore, there is also no need for a polyester
mixture or polyacrylate mixture of at least two resins having
different reactivities.
[0024] Co-reactants contemplated for the .beta.-hydroxyalkylamide
compounds used in accordance with the invention for preparing the
powder coating composition are polymers A) containing carboxylate
groups. Polymers which can be used are addition polymers,
polycondensates, and polyaddition compounds. In principle it is
possible to use any polymer which contains at least two carboxylate
groups and has a glass transition temperature T.sub.g greater than
40.degree. C. Polymers containing carboxylate groups that are
suitable for the powder coating materials of the invention are
those which have acid numbers of 5-350 mg KOH/g, preferably 15-150
mg KOH/g, with OH numbers <15 mg KOH/g. These polymers
preferably have at least two terminal carboxylate groups.
[0025] Particularly preferred in the context of the invention are
polyacrylates and/or polyesters containing carboxylate groups.
[0026] The polyesters A) containing carboxylate groups are
preferably polyester polycarboxylic acids prepared from polyols and
polycarboxylic acids and/or derivatives thereof. The glass
transition temperature T.sub.g of these acidic polyesters is
situated in a range from 40 to 80.degree. C., preferably 40 to
70.degree. C.; their acid number varies from 5-250 mg KOH/g,
preferably from 10 to 150 mg KOH/g, more preferably 12 to 120 mg
KOH/g. The OH numbers are below 15 mg KOH/g. They have an average
molecular weight M.sub.W of 1000 to 10 000 g/mol, preferably 1500
to 9000 g/mol, more preferably of 2000 to 8000 g/mol.
[0027] The polyesters containing carboxylate groups for use in
accordance with the invention are prepared using polycarboxylic
acids, such as oxalic, succinic, adipic,
2,2,4(2,4,4)-trimethyladipic, azelaic, sebacic, decanedicarboxylic,
dodecanedicarboxylic, fumaric, phthalic, isophthalic, terephthalic,
trimellitic, pyromellitic acid, for example. For the acidic
polyesters, polyols used are, by way of example, the following:
ethylene glycol, 1,2- and 1,3-propanediol, 1,2-, 1,3-, 1,4- and
2,3-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol,
neopentyl glycol, 1,12-dodecanediol,
2,2,4(2,4,4)-trimethyl-1,6-hexanediol, trimethylolpropane,
glycerol, pentaerythritol, 1,4-bishydroxymethylcyclohexane,
cyclohexane-1,4-diol, diethylene glycol, triethylene glycol, and
dipropylene glycol. It is of course also possible for
hydroxyl-containing polyesters, prepared by known methods from
polycarboxylic acids and polyols, to be reacted with polycarboxylic
acids and/or polycarboxylic anhydrides to give the polyester
polycarboxylic acids.
[0028] The polyester resins containing carboxylate groups are
prepared by known methods, by esterification or transesterification
of dihydric and/or polyhydric linear or branched, aliphatic or
cycloaliphatic polyols with polybasic, preferably dibasic or
polybasic aliphatic, cycloaliphatic or aromatic carboxylic acids or
their anhydrides or esters thereof, in the presence of an
esterification or transesterification catalyst at temperatures up
to about 250.degree. C. and under reduced pressure toward the
end.
[0029] Preferred polyols are 2,2-dimethyl-1,3-propanediol
(neopentyl glycol), ethylene glycol, 1,4-butanediol,
1,6-hexanediol, 1,4-dimethylolcyclohexane,
2,2-[bis(4-hydroxycyclohexyl)]propane, diethylene glycol,
dipropylene glycol, glycerol, pentaerythritol etc. The polyol
component preferably includes a high fraction of neopentyl glycol
in order to obtain very high glass transition temperatures.
Preferred polybasic carboxylic acids are terephthalic acid,
isophthalic acid, trimellitic acid, adipic acid, and/or
1,4-cyclohanedicarboxylic acid. The functionality of the preferred
polyester resins containing carboxylate groups is adjusted via the
ratio of dibasic to more-than-dibasic carboxylic acids.
[0030] Suitable acrylate polymers containing carboxylate groups
possess an acid number of 10-350 mg KOH/g, preferably 20 to 300 mg
KOH/g, and a glass transition temperature T.sub.g of greater than
40.degree. C., preferably of 45 to 100.degree. C., prepared by
homopolymerization or copolymerization of a monomer mixture.
[0031] The polyacrylate comprises carboxylic acid groups and may be
a homopolymer or a copolymer.
[0032] Monomers which can be used are acrylic acid and/or
methacrylic acid, C.sub.1-C.sub.40 alkyl esters and/or cycloalkyl
esters of methacrylic acid and/or acrylic acid, hydroxyalkyl
acrylates and/or hydroxyalkyl methacrylates, glycidyl methacrylate,
glycidyl acrylate, 1,2-epoxybutyl acrylate, 1,2-epoxybutyl
methacrylate, 2,3-epoxycyclopentyl acrylate, 2,3-epoxycyclopentyl
methacrylate, and also the analogous amides, where styrene and/or
derivatives thereof may also be present.
[0033] Preference is given to using butyl acrylate and/or butyl
methacrylate, 2-hydroxyethyl acrylate and/or 2-hydroxyethyl
methacrylate, methyl methacrylate, styrene (meth)acrylic acid, and,
optionally, further unsaturated monomers, with at least one monomer
containing carboxylate groups being used.
[0034] Further suitable monomers are (cyclo)alkyl esters of acrylic
or methacrylic acid having 2 to 18 carbon atoms in the (cyclo)alkyl
radical. Examples of suitable and preferentially suitable monomers
are ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl
(meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate,
tert-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, cyclohexyl
methacrylate, neopentyl methacrylate, isobornyl methacrylate,
3,3,5-trimethylcyclohexyl methacrylate, and stearyl
methacrylate.
[0035] Examples of monomers contemplated include styrene,
vinyltoluene, and ethylstyrene. Examples of are acrylic acid and
methacrylic acid, which are also used preferably, and also crotonic
acid, itaconic acid, fumaric acid, maleic acid, and citaconic
acid.
[0036] The polyacrylate preferably possesses an OH number of less
than 10 mg KOH/g, an acid number of 5 to 350 mg KOH/g, preferably
20 to 300 mg KOH/g, more preferably of 30 to 250 mg KOH/g, a Tg of
40 to 110.degree. C., preferably 45 to 100.degree. C., an M.sub.w
of 500 to 50 000 g/mol, preferably 1000 to 30 000 g/mol, more
preferably of 1500 to 20 000 g/mol.
[0037] As co-crosslinkers it is also possible to use epoxy resins.
Those contemplated include, for example, glycidyl ethers and
glycidyl esters, aliphatic epoxides, diglycidyl ethers based on
bisphenol A, and glycidyl methacrylates. Examples of epoxides of
these kinds are triglycidyl isocyanurate (TGIC trade name: e.g.,
ARALDIT PT 810, Huntsman; TEPIC G, Nissan; Taida TGIC, Anhui
Taida), mixtures of diglycidyl terephthalate and triglycidyl
trimellitate (trade names, e.g., ARALDIT PT 910 and PT 912,
Huntsman), glycidyl esters of Versatic acid (trade name, e.g.,
CARDURA E10, Shell), 3,4-epoxycyclohexylmethyl
3',4'-epoxycyclohexanecarboxylate (ECC), diglycidyl ethers based on
bisphenol A (trade name, e.g., EPIKOTE 828, Shell), ethylhexyl
glycidyl ether, butyl glycidyl ether, pentaerythritol tetraglycidyl
ether, (trade name, e.g., POLYPDX R16, UPPC AG), and also other
Polypox types having free epoxy groups. Mixtures can also be used.
Preference is given to using TEPIC G or ARALDIT PT 910 and 912.
Co-crosslinkers of these kinds can be used at up to 50% by weight
of the curing agent mixture that is used, composed of
.beta.-hydroxyalkylamide of the invention (matt curing agent) and
co-crosslinker.
[0038] Surprisingly it has been found that
.beta.-hydroxyalkylamides having a cyclohexane ring in the
framework, the .beta.-hydroxyalkylamides being present in solid
form below 150.degree. C., as crosslinkers for carboxyl-containing
polymers in powder coating materials, lead to matt surfaces after
curing.
[0039] The .beta.-hydroxyalkylamides B) may be prepared from
various starting materials. A known reaction is that of
.beta.-hydroxyalkylamines with esters of carboxylic acids, the
latter generating the parent structure (A). Depending on the
selection of the starting materials, the .beta.-hydroxyalkylamides
of the invention can be generated in this way.
[0040] Alternative but less preferred methods are based on other
carboxylic acid derivatives, such as carboxylic acids, carbonyl
chlorides, carboxylic anhydrides or other activated carboxylic acid
derivatives, for example, as starting materials, which are reacted
with .beta.-hydroxyalkylamines.
[0041] Suitable .beta.-hydroxyalkylamines are those which have
alkyl groups having at least 2 to 10 carbon atoms in the
hydrocarbon framework. The alkyl groups may be linear, branched or
else cyclic. The alkyl groups may likewise be substituted by
heteroatoms, preferably oxygen, nitrogen. Furthermore, these alkyl
groups may also contain functional groups, preferably carbonyl
groups, carboxyl groups, amino groups, amide groups, urethane
groups, and may carry an additional alkyl radical on the
nitrogen.
[0042] Preferably in this invention the .beta.-hydroxyalkylamides
are prepared from N-alkyl-1,2-alkanolamines and/or from
N,N-bis-2-hydroxyalkylamines and esters of cyclohexanedicarboxylic
acids.
[0043] Particular preference is given to using
.beta.-hydroxyalkylamines of the formulae II and/or III:
##STR00004##
where R.sup.1 is hydrogen, methyl, ethyl, propyl, R.sup.2 is
methyl;
##STR00005##
where radicals R.sup.1 simultaneously or independently of one
another are hydrogen, methyl, ethyl, propyl.
[0044] Particular preference in accordance with the invention is
given to using the following compounds as starting materials for
preparing .beta.-hydroxyalkylamides: diethanolamine (DEA),
di-isopropropanolamine (DIPA), di-sec-butanolamine,
N-methylethanolamine, N-methylisopropanolamine.
[0045] Suitable starting compounds for the substituent A in the
.beta.-hydroxyalkylamides of the invention are 1,2-, 1,3-, and
1-4-cyclohexanedicarboxylic acid derivatives, more particularly
dialkyl esters of cyclohexanedicarboxylic acids. These starting
compounds may have any desired cis/trans content.
[0046] Preference is given to using compounds of the formula IV
##STR00006##
where radicals R.sup.4 simultaneously or independently of one
another are methyl, ethyl, propyl, butyl.
[0047] Particular preference is given to using 1,4-substituted
cyclohexanedicarboxylic esters, very preferably dimethyl
1,4-cyclohexyldicarboxylate.
[0048] The .beta.-hydroxyalkylamides that are particularly
preferred in accordance with the invention, formed from dialkyl
1,4-cyclohexyldicarboxylates, preferably from dimethyl
1,4-cyclohexyldicarboxylate, have a trans content, based on the
position of the carboxyl groups on the cyclohexyl ring, of greater
than or equal to 70 mol %, preferably greater than 80 mol %, more
preferably of greater than 85 mol %. For preparing the preferred
.beta.-hydroxyalkylamides it is possible in this case to use
dialkyl 1,4-cyclohexyldicarboxylates having any desired trans
content.
[0049] The .beta.-hydroxyalkylamides (I) of the invention are
present in solid form below 150.degree. C., preferably below
170.degree. C., more preferably below 180.degree. C.
[0050] Particularly preferred .beta.-hydroxyalkylamides of the
invention have the following formulae:
##STR00007##
where R.sup.2 is methyl, or
##STR00008##
where R.sup.1A is hydrogen and R.sup.1B is methyl, ethyl, propyl,
or R.sup.1A is methyl, ethyl, propyl and R.sup.18 is hydrogen; and
A is a 1,4-disubstituted cyclohexane ring of the formula
##STR00009##
where the trans content of A is .gtoreq.70 mol %; and where the
.beta.-hydroxyalkylamides are present in solid form below
150.degree. C.
[0051] The .beta.-hydroxyalkylamide that is particularly preferred
in accordance with the invention, formed from dimethyl
1,4-cyclohexyldicarboxylate and diethanolamine with four
.beta.-hydroxyalkylamide groups per molecule of the formula
XII,
##STR00010##
has a trans content on the cyclohexyl ring of greater than or equal
to 70 mol %, preferably greater than 80 mol %, and more preferably
of greater than 85 mol %.
[0052] In order to achieve good technical coatings properties for
the powder coating composition, the ratio of
.beta.-hydroxyalkylamide groups to the carboxylate groups of the
polymers containing carboxylate groups is preferably between 0.5 to
1.5:1, more preferably between 0.8 to 1.2:1.
[0053] The powder coating composition may be admixed with the
auxiliaries and additives C) that are customary in powder coating
technology, such as flow control agents, e.g., polysilicones or
acrylates, light stabilizers, e.g., sterically hindered amines
and/or absorbers, degassing agents (e.g., benzophenone), modified
phenolic resins, catalysts and/or other auxiliary agents, as
described in EP 669 353, for example, in a total amount of 0.1% to
10% by weight. Fillers and pigments such as titanium dioxide, for
example, can be added in an amount of up to 50% by weight of the
overall composition.
[0054] In quantitative terms the constitution of the powder coating
compositions is as follows:
TABLE-US-00001 % by weight Inventive .beta.-hydroxyalkylamide 0.5
to 20 (matt curing agent B) preferably 1 to 15 Optional HAA curing
agent 0 to 10 preferably 0 to 8 Polymers A) containing 35 to 96
carboxylate groups preferably 50 to 80 Optionally co-crosslinker(s)
0 to 5 preferably 0 to 3 Additives, fillers, pigments etc. C) 0.1
to 50 preferably 5 to 40
[0055] The powder coating compositions of the invention exhibit
good storage stability in the storage test customary for powder
coating materials, in accordance with DIN EN ISO 8130-8, at
temperatures of 30.+-.1 and 40.+-.1.degree. C., and are storable
for >30 days.
[0056] In the particularly preferred embodiment of the invention,
the powder coating compositions of the invention comprise: [0057]
at least one polyester containing carboxylate groups and having an
acid number of 15 to 150 mg/KOH/g and a glass conversion
temperature of at least 40.degree. C., [0058] at least one
.beta.-hydroxyalkylamide of the invention having at least two or
more, preferably four, .beta.-hydroxyalkylamide groups, or else
mixtures thereof having the same and/or different functionality,
[0059] and also, optionally, further additives and auxiliaries
customary for powder coating materials, such as, for example,
wetting, flow control or degassing agents, heat stabilizers or UV
stabilizers, pigments, dyes, fillers, co-crosslinkers.
[0060] The invention provides a method for producing a powder
coating composition substantially comprising [0061] A) at least one
polymer containing carboxylate groups and having an acid number of
5 to 250 mg KOH/g and a glass transition temperature T.sub.g of
greater than 40.degree. C., and [0062] B) at least one
.beta.-hydroxyalkylamide having two or three or four
.beta.-hydroxyalkylamide groups per molecule of the formula I
[0062] ##STR00011## where R.sup.1 and R.sup.2 are, independently of
one another, identical or different radicals selected from alkyl
radical, cycloalkyl radical, aryl radical, aralkyl radical or
alkenyl radical having 1-24 carbon atoms, it being possible for the
radicals also to contain heteroatoms and/or functional groups, and
where R.sup.1 may also be hydrogen, and where R.sup.2 may also
be
##STR00012## and A is
##STR00013## where radicals R.sup.3 are, independently of one
another, identical or different radicals selected from hydrogen,
alkyl radical, cycloalkyl radical, aryl radical, aralkyl radical or
alkenyl radical having 1-24 carbon atoms, it being possible for the
radicals also to contain heteroatoms and/or functional groups, and
where two or more substituents R.sup.3 may be linked with one
another to form rings; where the .beta.-hydroxyalkylamides are
present in solid form below 150.degree. C.; [0063] C) optionally
auxiliaries and/or additives; where the ratio of
.beta.-hydroxyalkylamide groups to the carboxylate groups is
between 0.5:1 to 1.5:1; in the melt by joint extrusion of all the
components at temperatures between 80 to 150.degree. C.
[0064] The invention also provides a method for producing a powder
coating composition, comprising
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according
to formula XIIA as component B)
##STR00014##
[0065] which has the following parameters: [0066] 1. a trans
content on the cyclohexyl ring of greater than or equal to 70 mol
%, based on the total amount of all of the isomers of
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide that are
present, [0067] and [0068] 2. two endothermic peaks according to
DSC analysis (differential scanning calorimetry), where peak 1 is
situated in the region of 140-170.degree. C. with a maximum of
155-165.degree. C., and peak 2 is situated in the region of
170-210.degree. C. with a maximum of 175-207.degree. C., [0069] and
[0070] 3. the ratio of the enthalpies of the endothermic peak 1 to
the endothermic peak 2 is 1:1 to 1:5, [0071] and [0072] 4. the XRPD
spectrum of the powder sample in the x-ray diffractometer, measured
with Cu K.alpha. radiation (1.541 .ANG.), has the following
peaks:
TABLE-US-00002 [0072] Degrees 2theta .+-. Peak #. 0.2 degree 2theta
d (.ANG.) 1 14.90 5.94 2 16.70 5.31 3 17.40 5.09 4 21.20 4.19 5
21.60 4.11 6 26.00 3.43
[0073] The invention also provides a method for producing a powder
coating composition, comprising
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according
to the formula XIIA as component B)
##STR00015##
[0074] which has the following parameters: [0075] 1. a trans
content on the cyclohexyl ring of greater than or equal to 70 mol
%, based on the total amount of all of the isomers of
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide that are
present, [0076] and [0077] 2. two endothermic peaks according to
DSC analysis (differential scanning calorimetry), where peak 1 is
situated in the region of 140-170.degree. C. with a maximum of
155-165.degree. C., and peak 2 is situated in the region of
170-210.degree. C. with a maximum of 175-207.degree. C., [0078] and
[0079] 3. the ratio of the enthalpies of the endothermic peak 1 to
the endothermic peak 2 is 1:1 to 1:5, [0080] and [0081] 4. the XRPD
spectrum of the powder sample in the x-ray diffractometer, measured
with Cu K.alpha. radiation (1.541 .ANG.), has the following
peaks:
TABLE-US-00003 [0081] Degrees 2theta .+-. Peak #. 0.2 degree 2theta
d (.ANG.) 1 14.90 5.94 2 16.70 5.31 3 17.40 5.09 4 21.20 4.19 5
21.60 4.11 6 26.00 3.43
[0082] 5. and which, according to x-ray structural analysis of a
single crystal, has the following parameters:
TABLE-US-00004 [0082] Crystal system: Orthorhombic Space group:
Pbca Unit cell dimensions: a = 10.06350(10) .ANG. .alpha. =
90.degree.. b = 11.85290(10) .ANG. .beta. = 90.degree.. c =
14.6275(2) .ANG. .gamma. = 90.degree.. Volume: 1744.79(3)
.ANG..sup.3
[0083] The powder coating composition of the invention is produced
preferably in the melt by joint extrusion of all the components A)
to C) at temperatures between 80 to 150.degree. C. The extrudate is
subsequently cooled, ground, and sieved off or classified to a
particle size of <120 .mu.m, preferably <100 .mu.m. The
heat-curable and toxicologically flawless powder coating
composition produced in accordance with the invention therefore
consists of a matrix obtained by joint extrusion of all the
components.
[0084] In order to obtain the effect in accordance with the
invention, namely the formation of matt surfaces having a gloss to
DIN 67530/ISO 2813 of <50 at an incident angle of 60.degree., it
is possible to use numerous polymers containing carboxylate groups,
more particularly carboxylate-group-terminated polyesters or
polyacrylates, which differ in their functionality and reactivity.
The desired gloss can therefore be selected via the selected binder
partner (polyester) in conjunction with the hydroxyalkylamide of
the invention within a considerable spectrum (examples 1-7), with
the formulation being otherwise the same. Example (8) with the
polyacrylate deviates from this, since more crosslinker is needed
for the increased acid number, and a lower level of pigmentation
was selected in view of the anticipated greater brittleness.
[0085] The use of and the application of the powder coating
materials for producing coatings take place in accordance with
methods customary for powder coating materials, preferably by means
of an electrostatic powder coating sprayer device in accordance
with the triboelectric or corona method or in accordance with the
fluid-bed method.
[0086] At standard ambient temperatures, the powder coating
compositions produced in accordance with the invention possess good
storage stability and, after crosslinking between 150 to
220.degree. C., exhibit good technical coatings properties,
surfaces which flow out well in optical terms, and the low gloss
levels described.
[0087] In contrast to the prior art, the coatings obtained with the
powder coating compositions of the invention have visually very
attractive surfaces with good leveling (PCI evaluation table 8-10),
which, however, are matt (10-30 units) and/or semimatt (30-50
units), measured as reflectometer values to DIN 67530/ISO 2813 at
an incident angle of 60.degree., with no need for a dry blend or a
polyester mixture or polyacrylate mixture (one-shot blend).
[0088] Beyond this variation, the possibility additionally exists
of shifting the measured reflectometer value, to DIN 67530/ISO 2813
at an incident angle of 60.degree., to higher levels, up to the
re-acquisition of the high gloss of >80 scale divisions at the
60.degree. angle. This is accomplished by partially replacing the
matt curing agent B) of the invention with a standard commercial
.beta.-hydroxyalkylamide having two or more than two
.beta.-hydroxyalkylamide groups, or mixtures thereof having
different functionalities.
[0089] The invention provides the use of a powder coating
composition substantially comprising [0090] A) at least one polymer
containing carboxylate groups and having an acid number of 5 to 350
mg KOH/g and a glass transition temperature T.sub.g of greater than
40.degree. C., [0091] and [0092] B) at least one
.beta.-hydroxyalkylamide having two or three or four
.beta.-hydroxyalkylamide groups per molecule of the formula I
[0092] ##STR00016## [0093] where [0094] R.sup.1 and R.sup.2 are,
independently of one another, identical or different radicals
selected from alkyl radical, cycloalkyl radical, aryl radical,
aralkyl radical or alkenyl radical having 1-24 carbon atoms, it
being possible for the radicals also to contain heteroatoms and/or
functional groups, and where R.sup.1 may also be hydrogen, [0095]
and where R.sup.2 may also be
[0095] ##STR00017## [0096] and [0097] A is
[0097] ##STR00018## where radicals R.sup.3 are, independently of
one another, identical or different radicals selected from
hydrogen, alkyl radical, cycloalkyl radical, aryl radical, aralkyl
radical or alkenyl radical having 1-24 carbon atoms, it being
possible for the radicals also to contain heteroatoms and/or
functional groups, and where two or more substituents R.sup.3 may
be linked with one another to form rings; where the
.beta.-hydroxyalkylamides are present in solid form below
150.degree. C.; [0098] C) optionally auxiliaries and/or additives;
[0099] where the ratio of .beta.-hydroxyalkylamide groups to the
carboxylate groups is between 0.5:1 to 1.5:1; [0100] for producing
coatings having matt surfaces, having a gloss to DIN 67530/ISO 2813
of <50 at an incident angle of 60.
[0101] Provided especially preferably by the invention is a powder
coating composition which has the compound
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according
to the formula XIIA as component B),
##STR00019##
which has the following parameters: [0102] 1. a trans content on
the cyclohexyl ring of greater than or equal to 70 mol %, based on
the total amount of all of the isomers of
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide that are
present, and [0103] 2. two endothermic peaks according to DSC
analysis (differential scanning calorimetry), where peak 1 is
situated in the region of 140-170.degree. C. with a to maximum of
155-165.degree. C., and peak 2 is situated in the region of
170-210.degree. C. with a maximum of 175-207.degree. C., [0104] and
[0105] 3. the ratio of the enthalpies of the endothermic peak 1 to
the endothermic peak 2 is 1:1 to 1:5, and [0106] 4. the XRPD
spectrum of the powder sample in the x-ray diffractometer, measured
with Cu K.alpha. radiation (1.541 .ANG.), has the following
peaks:
TABLE-US-00005 [0106] Degrees 2theta .+-. Peak #. 0.2 degree 2theta
d (.ANG.) 1 14.90 5.94 2 16.70 5.31 3 17.40 5.09 4 21.20 4.19 5
21.60 4.11 6 26.00 3.43
[0107] Description of the Particularly Preferred Component B):
[0108] Provided more preferably by the invention is a powder
coating composition comprising the .beta.-hydroxyalkylamide
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according
to the formula XIIA as component B), having a trans content on the
cyclohexyl ring of greater than or equal to 70 mol %, preferably
greater than 80 mol %, and more preferably of greater than 85 mol
%, based on the total amount of all of the isomers of
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide that are
present.
[0109] Additionally this .beta.-hydroxyalkylamide of the invention
used as component B),
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according
to the formula XIIA, has two endothermic peaks according to DSC
analysis (differential scanning calorimetry): first a peak with a
maximum (peak 1) of about 160.degree. C., and a further, second
peak with a maximum (peak 2) of about 190.degree. C.; see the
figures relating to the examples. Preferably, the first peak is
situated in the range of 140-170.degree. C. with a maximum of
155-165.degree. C. and the second peak is situated in the range of
170-210.degree. C. with a maximum of 175-207.degree. C.
[0110] More preferably, the first peak is situated in the range of
155-170.degree. C. with a maximum of 158-165.degree. C., and the
second peak is situated in the range of 170-210.degree. C. with a
maximum of 180-205.degree. C.
[0111] The ratio of the enthalpies of the endothermic peak 1
(.about.160.degree. C.) to the endothermic peak 2
(.about.190.degree. C.) may be 1:1 to 1:5, preferably 1:1 to
1:3.
[0112] The DSC measurements were carried out in accordance with DIN
EN ISO 11357-1 of March 2010. A heat flow difference calorimeter
from the manufacturer Mettler-Toledo, model DSC 821, was used. The
samples are run once from -30.degree. C. to 250.degree. C. at 10
K/min.
[0113] The XRPD measurements on powder samples were carried out in
an x-ray diffractometer using Cu K.alpha. radiation (1.541 .ANG.).
In accordance with FIG. 9, the following significant and
characteristic 6 peaks of the .beta.-hydroxyalkylamide
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according
to the formula XIIA were found:
TABLE-US-00006 Degrees 2theta .+-. Peak # 0.2 degree 2 theta d
(.ANG.) 1 14.90 5.94 2 16.70 5.31 3 17.40 5.09 4 21.20 4.19 5 21.60
4.11 6 26.00 3.43
[0114] Especially preferred as component B) is the
.beta.-hydroxyalkylamide
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according
to the formula XIIA having a trans content on the cyclohexyl ring
of greater than or equal 92 mol %, preferably greater than 94 mol
%, and more preferably of greater than 96 mol %, and very
preferably of greater than 98 mol %, based on the total amount of
all of the isomers of
N,N,N',W-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide that are
present.
[0115] The .beta.-hydroxyalkylamide of the formula XIIA of the
invention that is used as component B) is present in solid form
below 175.degree. C., preferably below 180.degree. C., and more
preferably of below 185.degree. C.
[0116] The .beta.-hydroxyalkylamide of the formula XIIA of the
invention that is used as component B), having the features 1. to
4, was investigated by means of x-ray structural analysis of a
single crystal. Comprehensive details relating to the measurement
are summarized in annex 1. The x-ray structural analysis of a
single crystal gave the following result for the structure:
TABLE-US-00007 Crystal system: Orthorhombic Space group: Pbca Unit
cell dimensions: a = 10.06350(10) .ANG. .alpha. = 90.degree.. b =
11.85290(10) .ANG. .beta. = 90.degree.. c = 14.6275(2) .ANG.
.gamma. = 90.degree.. Volume: 1744.79(3) .ANG..sup.3
[0117] The values within the brackets indicate the measurement
accuracy, in each case in plus and minus, for the corresponding
last digit or last two digits, respectively.
[0118] Provided with very particular preference by the invention is
a powder coating composition which comprises the compound
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according
to the formula XIIA as component B)
##STR00020##
which has the following parameters: [0119] 1. a trans content on
the cyclohexyl ring of greater than or equal to 70 mol %, based on
the total amount of all of the isomers of
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide that are
present, [0120] and [0121] 2. two endothermic peaks according to
DSC analysis (differential scanning calorimetry), where peak 1 is
situated in the region of 140-170.degree. C. with a maximum of
155-165.degree. C., and peak 2 is situated in the region of
170-210.degree. C. with a maximum of 175-207.degree. C., [0122] and
[0123] 3. the ratio of the enthalpies of the endothermic peak 1 to
the endothermic peak 2 is 1:1 to 1:5, and [0124] 4. the XRPD
spectrum of the powder sample in the x-ray diffractometer, measured
with Cu K.alpha. radiation (1.541 .ANG.), has the following
peaks:
TABLE-US-00008 [0124] Degrees 2theta .+-. Peak #. 0.2 degree 2theta
d (.ANG.) 1 14.90 5.94 2 16.70 5.31 3 17.40 5.09 4 21.20 4.19 5
21.60 4.11 6 26.00 3.43
[0125] 5. and which, according to x-ray structural analysis of a
single crystal, has the following parameters:
TABLE-US-00009 [0125] Crystal system: Orthorhombic Space group:
Pbca Unit cell dimensions: a = 10.06350(10) .ANG. .alpha. =
90.degree.. b = 11.85290(10) .ANG. .beta. = 90.degree.. c =
14.6275(2) .ANG. .gamma. = 90.degree.. Volume: 1744.79(3)
.ANG..sup.3
Preparation
[0126] The particularly preferred
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according
to the formula XIIA which is used as component B) is obtainable by
various methods:
[0127] First of all, as described precisely earlier on above, the
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according
to the formula XIIA is prepared, preferably solventlessly, in an
extruder, intensive compounder, intensive mixer or static mixer,
preferably in an extruder. For this preparation, temperatures of
100 to 180.degree. C. are employed. This is followed by
recrystallization from a suitable solvent, preferably water. After
dissolution at temperatures of 20-100.degree. C. and
crystallization, the
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according
to the formula XIIA is obtained with the above-stated parameters.
It can then, subsequently, be washed with alcohols, preferably
methanol, and dried. Drying takes place preferably at temperatures
of 20-90.degree. C., and can also take place under reduced
pressure.
[0128] Another variant of the preparation takes place as described
precisely earlier on above, by the
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according
to the formula XIIA being prepared in an extruder, intensive
compounder, intensive mixer or static mixer, preferably in an
extruder, preferably solventlessly. In this case temperatures of
100 to 180.degree. C. are employed. This is followed by a thermal
conditioning at temperatures of 50-100.degree. C., preferably at
temperatures of 70-85.degree. C. The time is more than 6 hours,
preferably more than 12 hours. Thermal conditioning may also take
place under reduced pressure.
[0129] The particularly preferred
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according
to the formula XIIA that is used as component B) may also take
place discontinuously in a solvent, in other words in a batch
method.
[0130] The reaction is carried out in customary reactors. Operation
may be unpressurized, using a reflux condenser, or under pressure,
with a closed reactor.
[0131] The synthesis is carried out in a solvent, preferably in
alcohols, preferably methanol. The amount of solvent added is
greater than 10% by weight, preferably greater than 15% by weight,
based on the total amount of all the reactants (starting materials)
used. This operation may take place under reflux, or else at
relatively low temperatures, and also relatively high temperatures,
under pressure. The preparation takes place at temperatures of 20
to 120.degree. C., preferably at 60 to 90.degree. C., more
preferably at 70 to 85.degree. C.
[0132] After crystallization has taken place, the
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according
to the formula XIIA is obtained, with the parameters stated
above.
[0133] Furthermore, the
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according
to the formula XIIA can be prepared in closed apparatus under
pressure at temperatures of 60 to 140.degree. C. without addition
of solvents.
[0134] The N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide
according to the formula XIIA prepared in this way in a batch
method can be recrystallized from suitable solvents, preferably
from water or alcohols, preferably from methanol.
[0135] Furthermore, the preparation of the
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according
to the formula XIIA may also take place discontinuously without
solvents.
[0136] The reaction is carried out in customary reactors. It is
possible here to operate using a reflux condenser. The preparation
takes place preferably at temperatures of 20 to 140.degree. C.,
preferably 60 to 90.degree. C., more preferably at 70 to 85.degree.
C. The .beta.-hydroxyalkylamide obtained in this way in a batch
method is then recrystallized from suitable solvents, preferably
from water or alcohols, preferably from methanol. After
crystallization has taken place, the
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according
to the formula XIIA is obtained, with the parameters stated
above.
[0137] The concentration of all of the isomers of
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide in the end
product after its preparation is 75% by mass, preferably 80% by
mass, and more preferably 85% by mass.
[0138] This .beta.-hydroxyalkylamide characterized and described
here, N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide of
the formula XIIA, produces far-reaching matting in powder coatings,
with a gloss of less than 50 scale divisions at the 60.degree.
angle, as has been shown in the examples. This product of the
formula XIIA therefore differs clearly from the
.beta.-hydroxyalkylamide disclosed in accordance with laid-open
specification KR 10-2009-0111720 (and from the
.beta.-hydroxyalkylamide from Korean Ind. Eng. Chem., vol. 20, No.
2, April 2009, 195-200), as demonstrated there in FIG. 2 on page
15, which has only one peak according to DSC analysis at about
190.degree. C., and, as shown by comparative example 4c, does not
lead to coatings having matt surfaces.
[0139] The invention also provides the use of a powder coating
composition as described above, comprising
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according
to formula XIIA as a component
##STR00021##
which has the following parameters: [0140] 1. a trans content on
the cyclohexyl ring of greater than or equal to 70 mol %, based on
the total amount of all of the isomers of
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide that are
present, [0141] and [0142] 2. two endothermic peaks according to
DSC analysis (differential scanning calorimetry), where peak 1 is
situated in the region of 140-170.degree. C. with a maximum of
155-165.degree. C., and peak 2 is situated in the region of
170-210.degree. C. with a maximum of 175-207.degree. C., [0143] and
[0144] 3. the ratio of the enthalpies of the endothermic peak 1 to
the endothermic peak 2 is 1:1 to 1:5, [0145] and [0146] 4. the XRPD
spectrum of the powder sample in the x-ray diffractometer, measured
with Cu K.alpha. radiation (1.541 .ANG.), has the following
peaks:
TABLE-US-00010 [0146] Degrees 2theta .+-. Peak #. 0.2 degree 2theta
d (.ANG.) 1 14.90 5.94 2 16.70 5.31 3 17.40 5.09 4 21.20 4.19 5
21.60 4.11 6 26.00 3.43
for producing coatings having matt surfaces with <50 gloss
units, measured as reflectometer values to DIN 67530/ISO 2813 with
an incident angle of 60.degree..
[0147] The invention also provides the use of a powder coating
composition as described above, comprising
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according
to the formula XIIA as component B)
##STR00022##
which has the following parameters: [0148] 1. a trans content on
the cyclohexyl ring of greater than or equal to 70 mol %, based on
the total amount of all of the isomers of
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide that are
present, and [0149] 2. two endothermic peaks according to DSC
analysis (differential scanning calorimetry), where peak 1 is
situated in the region of 140-170.degree. C. with a maximum of
155-165.degree. C., and peak 2 is situated in the region of
170-210.degree. C. with a maximum of 175-207.degree. C., and [0150]
3. the ratio of the enthalpies of the endothermic peak 1 to the
endothermic peak 2 is 1:1 to 1:5, and [0151] 4. the XRPD spectrum
of the powder sample in the x-ray diffractometer, measured with Cu
K.alpha. radiation (1.541 .ANG.), has the following peaks:
TABLE-US-00011 [0151] Degrees 2theta .+-. Peak #. 0.2 degree 2theta
d (.ANG.) 1 14.90 5.94 2 16.70 5.31 3 17.40 5.09 4 21.20 4.19 5
21.60 4.11 6 26.00 3.43
[0152] 5. and which, according to x-ray structural analysis of a
single crystal, has the following parameters:
TABLE-US-00012 [0152] Crystal system: Orthorhombic Space group:
Pbca Unit cell dimensions: a = 10.06350(10) .ANG. .alpha. =
90.degree.. b = 11.85290(10) .ANG. .beta. = 90.degree.. c =
14.6275(2) .ANG. .gamma. = 90.degree.. Volume: 1744.79(3)
.ANG..sup.3
for producing coatings having matt surfaces with <50 gloss
units, measured as reactometer values to DIN 67530/ISO 2813 at an
incident angle of 60.degree..
EXAMPLES
[0153] The following examples and tables 1, 2, and 3 characterize
the composition of the coating system and the properties of the
respective coating after its application and curing.
Materials Used:
1) .beta.-Hydroxyalkylamide
[0154] a) .beta.-Hydroxyalkylamide (matt cutting agent) based on
1,4-cyclohexanedicarboxylic acid and diethanolamine, having four
.beta.-hydroxyalkylamide groups per molecule, of the formula XII
has a trans content on the cyclohexyl ring of >90% (Evonik
Degussa GmbH, D).
TABLE-US-00013 [0154] trans-N,N,N',N'-tetrakis(2-hydroxyethyl) % by
mass 95.30 cyclohexyl-1,4-diamide.sup.1
cis-N,N,N',N'-tetrakis(2-hydroxyethyl) % by mass 0.28
cyclohexyl-1,4-diamide.sup.1 .SIGMA.
N,N,N',N'-tetrakis(2-hydroxyethyl) % by mass 95.58
cyclohexyl-1,4-diamide.sup.1 DEA.sup.1 % by mass 0.18 OH number mg
KOH/g 616 Base number mg KOH/g 3 Melting range .degree. C. 194-201
.sup.1Analytical values by GC OH number: DIN 53240 Base number: DIN
53176 Melting range: DIN EN ISO 3146
[0155] b) VESTAGON.RTM. HA 320, OH number: 660-740 mg KOH/g,
melting range: 115-130.degree. C., (Evonik Degussa GmbH, D)
2) Polymers Containing Carboxylate Groups--Resins
[0155] [0156] a) Amorpher polyester: [0157] Crylcoat.RTM. 2617-3,
AN number: 33 mg KOH/g, Tg: 61.degree. C., (Cytec Inc., USA) [0158]
Crylcoat.RTM. 2618-3, AN number: 35 mg KOH/g, Tg: 61.degree. C.,
(Cytec Inc., USA) [0159] Crylcoat.RTM. E 36988, AN number: 30 mg
KOH/g, Tg: 54.degree. C., (Cytec Inc., USA) [0160] Uralac.RTM. P
800, AN number: 28 mg KOH/g, Tg: 61.degree. C., DSM Resins B.V.,
NL) [0161] Uralac.RTM. P 865, AN number: 35 mg KOH/g, Tg:
56.degree. C., (DSM Resins B.V., NL) [0162] Pulverol.RTM. 8120, AN
number: 33 mg KOH/g, Tg: 60.degree. C., (Neochimiki LV s.a., GR)
[0163] Pulverol.RTM. 8123, AN number: 33 mg KOH/g, Tg: 60.degree.
C., (Neochimiki LV s.a., GR) [0164] b) Polyarclate [0165]
Joncryl.RTM. 819, AN number: 75 mg KOH/g, Tg: 57.degree. C., (BASF
AG., D)
3) Co-Crosslinker
[0165] [0166] a) Triglycidyl isocyanurate: [0167] TEPIC.RTM.G,
Epoxy equiv: <110 g/eq, Melting range: 90-125.degree. C.,
(Nissan Chemical Ind. Ltd., J)
4) Other Formulating Ingredients:
[0167] [0168] Titanium dioxide, Kronos.RTM. 2160, (Kronos Titan
GmbH, D), [0169] Resiflow.RTM. PV 88, (Worlee-Chemie GmbH, D),
[0170] Benzoin, (Merck-Schuchard, D).
Powder Coating Material and Coating
[0171] The powder coating material was produced first by mixing all
of the components as per tables 1 and 2 at room temperature in a
MIT mixer at 500 rpm for 120 seconds and then, second, by joint
extrusion in the melt at a temperature (barrel) of 90.degree. C.
(about 130.degree. C. melt temperature). The stoichiometric ratio
of acid groups of the polyester or polyacrylate to OH groups of the
.beta.-hydroxyalkylamides (curing agents) was about 1:1. When
co-crosslinkers were used, they were taken into account
stoichiometrically in respect of the amount of curing agent.
[0172] The extrudate was subsequently cooled, ground, and sieved to
a particle size of <100 .mu.m. The powder coating material
produced in this way was applied using an electrostatic powder
spraying unit at 60 KV to degreased steel panels (deep-drawn steel
from Kruppel 210.times.70.times.0.8 mm) and/or aluminum panels
(Q-panel AL-36 5005 H 14/08 0.8 mm) and baked in a forced-air
drying oven at between 160 to 220.degree. C. The cured coating
films had a film thickness of about 55-65 .mu.m. The example data
relate to a baking time of 20 minutes at 200.degree. C.
TABLE-US-00014 TABLE 1 Testing according to characteristics of
different polyesters and polyacrylate Formulating examples with
inventive .beta.-hydroxyalkylamide 1a (matt cutting agent) and
different resins Example 1 2 3 4 5 6 7 8 .beta.-Hydroxyalkylamide %
by wt. 3.00 3.00 3.00 3.00 3.00 3.00 3.00 7.80 1a CRYLCOAT .RTM.
2618-3 % by wt. 60.70 -- -- -- -- -- -- -- CRYLCOAT .RTM. E 36988 %
by wt. -- 60.70 -- -- -- -- -- -- PULVEROL .RTM. 8120 % by wt. --
-- 60.70 -- -- -- -- -- URALAC .RTM. P 800 % by wt. -- -- -- 60.70
-- -- -- -- URALAC .RTM. P 865 % by wt. -- -- -- -- 60.70 -- -- --
CRYLCOAT .RTM. 2617-3 % by wt. -- -- -- -- -- 60.70 -- -- PULVEROL
.RTM. 8123 % by wt. -- -- -- -- -- -- 60.70 -- JONCRYL .RTM. SCX
819 % by wt. -- -- -- -- -- -- -- 66.00 KRONOS .RTM. 2160 % by wt.
35.00 35.00 35.00 35.00 35.00 35.00 35.00 25.00 RESIFLOW .RTM. PV
88 % by wt. 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 Benzoin % by
wt. 0.30 0.30 0.30 0.30 0.30 0.30 0.30 0.20 Curing at 200.degree.
C. min 20 20 20 20 20 20 20 30 Film thickness .mu.m 67-71 57-66
57-59 57-61 66-73 54-60 52-59 58-62 Erichsen cupping mm >8 4
>8 5 >8 >8 >8 6 Ball impact direct in lb >80 >80
>80 >80 >80 >80 >80 20 Ball impact reverse in lb 60
60 80 50 80 60 80 <10 Gloss 60.degree. units 36 53 44 51 30 33
45 33 Gloss 85.degree. units 44-48 62-67 53-59 60-64 39-43 41-43
55-61 59-65
[0173] By replacing the inventive .beta.-hydroxyalkylamide 1a) by a
standard commercial .beta.-hydroxyalkylamide, such as VESTAGON HA
320 1b), or else by mixtures with other commercial products with
the same and/or different functionality, it is possible to retain
the gloss, at low levels of admixture, or, if desired, to shift it
to higher values, with increased additivation or replacement. This
is shown here in examples 9 to 13 by reference to a polyester.
[0174] Formulating examples with inventive .beta.-hydroxyalkylamide
1a (matt curing agent) and different resins, and with commercial
.beta.-hydroxyalkylamide 1b)
TABLE-US-00015 TABLE 2 Example 9 10 11 12 13
.beta.-Hydroxyalkylamide % by wt. 1.90 1.75 1.50 1.00 0.25 1a
VESTAGON HA 320 % by wt. 1.10 1.25 1.50 2.00 2.75 1b CRYLCOAT .RTM.
2617-3 % by wt. 60.70 60.70 60.70 60.70 60.70 KRONOS .RTM. 2160 %
by wt. 35.00 35.00 35.00 35.00 35.00 RESIFLOW .RTM. PV 88 % by wt.
1.00 1.00 1.00 1.00 1.00 Benzoin % by wt. 0.30 0.30 0.30 0.30 0.30
Curing at 200.degree. C. min 20 20 20 20 20 Film thickness .mu.m
57-66 57-59 57-61 66-73 54-60 Erichsen cupping mm >8 >8 >8
>8 >8 Ball impact direct in lb >80.00 >80.00 >80.00
>80.00 >80.00 Ball impact reverse in lb 80 >80 >80
>80 >80 Gloss 60.degree. units 53 57 62 83 94
[0175] As co-crosslinkers it is also possible to use epoxy resins.
Examples contemplated include glycidyl ethers and glycidyl esters,
aliphatic epoxides, diglycidyl ethers based on bisphenol A, and
glycidyl methacrylates. Examples of such epoxides are triglycidyl
isocyanurate (TGIC trade names, e.g., ARALDIT PT 810, Huntsman;
TEPIC G, Nissan; Taida TGIC, Anhui Taida), mixtures of diglycidyl
terephthalate and triglycidyl trimellitate (trade names, e.g.,
ARALDIT PT 910 and PT 912, Huntsman), glycidyl esters of Versatic
acid (trade name, e.g., CARDURA E10, Shell),
3,4-epoxycyclohexylmethyl 3',4'-epoxycyclohexanecarboxylate (ECC),
diglycidyl ethers based on bisphenol A (trade name, e.g., EPIKOTE
828, Shell), ethylhexyl glycidyl ether, butyl glycidyl ether,
pentaerythritol tetraglycidyl ether, (trade name, e.g., POLYPDX R
16, UPPC AG), and also other Polypox types having free epoxy
groups. Mixtures can also be used. Preference is given to using
TEPIC G or ARALDIT PT 910 and 912.
[0176] Co-crosslinkers of these kinds can be used at up to 50% by
weight of the curing agent mixture used, composed of matt curing
agent and co-crosslinker.
[0177] Formulating examples with inventive .beta.-hydroxyalkylamide
1a (matt curing agent) and co-crosslinker
TABLE-US-00016 TABLE 3 Example 14 15 16 17 .beta.-Hydroxyalkylamide
% by wt. 2.95 2.90 2.80 2.50 1a TEPIC .RTM. G 3a % by wt. 0.05 0.10
0.20 0.50 CRYLCOAT .RTM. 2617-3 % by wt. 60.70 60.70 60.70 60.70
KRONOS .RTM. 2160 % by wt. 35.00 35.00 35.00 35.00 RESIFLOW .RTM.
PV 88 % by wt. 1.00 1.00 1.00 1.00 Benzoin % by wt. 0.30 0.30 0.30
0.30 Curing at 200.degree. C. min 20 20 20 20 Film thickness .mu.m
50-56 50-55 53-62 45-51 Erichsen cupping mm >8 >8 >8 >8
Ball impact direct in lb 60 >80 >80 >80 Ball impact
reverse in lb <10 >80 >80 >80 Gloss 60.degree. units 32
44 45 53 Gloss 85.degree. units 40-45 58-62 57-59 65-67
[0178] Examples 3a, b; 4a, b, c, d; 5
The DSC Measurements
[0179] The DSC measurements were carried out in accordance with DIN
EN ISO 11357-1 of March 2010.
[0180] A heat flow difference calorimeter from the manufacturer
Mettler-Toledo, model: DSC 821 with serial number 5116131417 was
used. The samples are run once from -30.degree. C. to 250.degree.
C. at 10 K/min.
Comprehensive Description of the Measurement Method:
[0181] 1. Type (heat flow difference calorimeter or
power-compensated calorimeter), model and manufacturer of the DSC
instrument used; [0182] 2. Material, nature, and type, and also,
when necessary, mass of the crucibles used; [0183] 3. Nature,
purity, and volume flow rate of the flushing gas used; [0184] 4.
Nature of the calibration method and details of the calibrating
substances used, including source, mass, and other properties
significant for calibration; [0185] 5. Details concerning sampling,
sample preparation, and conditioning 1: Heat flow difference
calorimeter [0186] Manufacturer: Mettler-Toledo [0187] Model: DSC
821 [0188] Serial number: 5116131417
2: Crucible Material: Ultrapure Aluminum
[0188] [0189] Size: 40 .mu.l, without pin, [0190] Mettler order
No.: ME-26763 [0191] Mass including lid: about 48 mg
3: Flushing Gas: Nitrogen
[0191] [0192] Purity: 5.0 (>99.999% by volume) [0193] Volume
flow rate: 40 ml/min
4: Calibrating Method: Single
[0193] [0194] Material 1: indium [0195] Mettler calibrating set
ME-51119991 [0196] Mass: about 6 mg per weighing [0197] Calibration
of temperature (onset) and heat flow [0198] Material 2: deionized
water [0199] Taken from in-house system [0200] Mass: about 1 mg per
weighing [0201] Calibration of temperature (onset) 5: Sampling:
from Supplied Sample Vials [0202] Sample weighing mass: 8 to 10 mg
[0203] Sample preparation: pressed on the crucible base using die
[0204] Crucible lid: perforated [0205] Measurement program: -30 to
250.degree. C. 10 K/min 1.times.
Description of the XRPD Measurement:
[0206] The powder sample is pressed into a powder holder and is
measured in a Philips PW1800 x-ray diffractometer using Cu K.alpha.
radiation (1.541 .ANG.) under the following conditions:
Excitation: 40 kV, 45 mA
[0207] Measuring range: 3.degree..ltoreq.2.theta..ltoreq.40.degree.
Step size: 0.1.degree. (2Theta) Time per step: 20 s Rotation: 1/4
revolution/sec Receiving slit: coarse Divergence slit:
automatic
Examples 3a, b; 4a, b, c, d
TABLE-US-00017 [0208] Product description, Substances used
manufacturer Diethanolamine (DEA) Dow Chemical Dimethyl
1,4-cyclohexyldicarboxylate Dimethylester of 1,4- (DMCD)
(distilled) trans content cyclohexanedicarboxylic acid, 15-35 mol %
EASTMAN Sodium methoxide 30% strength in methanol
Example 3a
[0209] A three-neck flask with reflux condenser and glass stirrer
is charged with 92.24 g of dimethyl 1,4-cyclohexyldicarboxylate
with 96.91 g of diethanolamine, 10.84 g of 30% strength sodium
methoxide in methanol, and 52 g of methanol. A homogeneous solution
is formed.
[0210] The batch is boiled in an oil heating bath under reflux with
stirring for six hours (bath temperature 80.degree. C.). The
product begins to precipitate after about 0.5 hour.
[0211] The reaction mixture is left to cool, during which further
product crystallizes out. The precipitated product is subsequently
separated from methanol by filtration and then dried. The yield is
more than 80% of theory. Table 3a
[0212] Obtained accordingly is an
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according
to formula XIIA having two endothermic peaks (1st at about
160.degree. C. and 2nd at about 190.degree. C.) in the DSC as per
FIG. 1 and the XRPD spectrum as per FIG. 5 and table 5. This
product thus produced produces far-reaching matting in powder
coatings, with a gloss of less than 50 scale divisions at a
60.degree. angle, table 3a.
Example 3b
[0213] The product produced in 3a is dissolved in boiling water,
then slowly cooled again and, after crystallization has taken
place, briefly washed with methanol. Table 3a This product exhibits
the two endothermic peaks, see FIG. 2, with matting effect present
in the resultant powder coatings, of 29 scale divisions at the 60
degree angle, table 3a.
TABLE-US-00018 TABLE 3A End products from batch preparation
examples 3a-3b and their characterization by GC analysis.sup.1)
Example 3a 3b Starting material -- 3a Preparation Batch preparation
as Boil 3a in deionized water described in example cool slowly 3a
crystallize wash with methanol dry under vacuum .sup.1)DEA % by
mass 1.22 <0.1
.sup.1)trans-N,N,N',N'-Tetrakis(2-hydroxyethyl)cyclohexyl-1,4- % by
mass 89.34 91.81 diamide
.sup.1)cis-N,N,N',N'-Tetrakis(2-hydroxyethyl)cyclohexyl-1,4- % by
mass 0.74 0.00 diamide .SIGMA.
N,N,N',N'-Tetrakis(2-hydroxyethyl)cyclohexyl-1,4- % by mass 90.08
91.81 diamide Ratio of .sup.1)trans-N,N,N',N'-tetrakis(2- mol %
99.2 1000 hydroxyethyl)cyclohexyl-1,4-diamide to
.sup.1)cis-N,N,N',N'-tetrakis(2- mol % 0.8 0.0
hydroxyethyl)cyclohexyl-1,4-diamide OH number mg KOH/g 629 -- Base
number -- 22 -- DSC: 1.sup.st endo. peak - .DELTA. H .degree. C. -
J/g 159-54 164-63 DSC: 2.sup.nd endo. peak - .DELTA. H .degree. C.
- J/g 186-89 203-124 .sup.1)Analytical values by GC GC after
silylation with Silyl 991 (BSTFA-TMCS 99: 1) from Macherey and
Nagel order No. 701.490.150. Silylation: 1 ml Silyl 991, 1 ml
pyridine, 35 mg reaction product, 35 mg C-18 hydrocarbon as
internal standard, heat for 30 minutes at 80.degree. C. in a closed
ampoule. Powder coating data PC experiment number 3a 3b HAA
crosslinker % by mass 3.00 3.00 CRYLCOAT .RTM. 2617-3 % by mass
60.70 60.70 KRONOS .RTM. 2160 % by mass 35.00 35.00 RESIFLOW .RTM.
PV 88 % by mass 1.00 1.00 Benzoin % by mass 0.30 0.30 Total % by
mass 100.00 100.00 Curing min @.degree. C. 30 @ 200 30 @ 200 Film
thickness .mu.m 64-70 70-73 Gloss at 60.degree. Sc. div. 30 29 OH
number: DIN 53240 Base number: DIN 53176
Preparation Example A
Preparation of a .beta.-hydroxyalkylamide of the formula XIIA from
dimethyl-1,4-cyclohexyldicarboxylate and diethanolamine in an
extruder
TABLE-US-00019 [0214] Product description, Substances used
manufacturer Diethanolamine (DEA) Dow Chemical Dimethyl
1,4-cyclohexyldicarboxylate Dimethylester of 1,4- (DMCD) trans
content 15-35 mol % cyclohexanedicarboxylic acid, EASTMAN Sodium
methoxide 30% strength in methanol
Operation Took Place with Three Streams: Stream 1 consisted of DMCD
Stream 2 consisted of DEA Stream 3 consisted of the catalyst, the
methanolic sodium methoxide solution.
[0215] The streams were metered so that the molar ratio between
dimethyl 1,4-cyclohexyldicarboxylate and diethanolamine was
1:1.95.
[0216] The total amount of catalyst (only sodium methoxide,
calculated on solvent-free basis), based on the total formula, was
0.50% to 3.0%.
[0217] Stream 1 was fed at a rate of 10.0 kg/h into the first
barrel of a twin-extruder (ZSK 30, 32 d) (stream temperature 80 to
130.degree. C.).
[0218] Stream 2 was fed in at a rate of 9.9 kg/h (stream
temperature 65 to 145.degree. C.).
[0219] Stream 3 was introduced through a nozzle from entry into the
extruder into stream 2 (0.5 to 2.0 kg/h).
[0220] The extruder used consisted of 8 barrels, which were
separately heatable and coolable. Barrels 1-5: 160.degree. C.,
barrels 6-8: 120-160.degree. C.
[0221] Barrels 3, 5, and 8 were provided with a vacuum dome (100 to
600 mbar).
[0222] The extruder screws were fitted with conveying elements.
Ahead of the vacuum domes, kneading blocks were installed.
[0223] All of the temperatures represented setpoint temperatures.
Regulation took place via electrical heating or water cooling. The
extruder head was likewise heated electrically (100-160.degree.
C.).
[0224] The screw speed was 300 rpm. The reaction product was
conveyed out of the extruder using a gear pump. The total
throughput was 20 kg/h.
[0225] The end product was cooled via a pipe section or via an
extruder and was guided onto a cooling belt, and cooled
further.
Example 4a and 4b
[0226] 4a
[0227] An N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide
with the product data 4a is prepared in the same way as described
in example A in an extruder (Werner and Pfleiderer ZSK 30, 32 d).
Table 4
4b
[0228] This product, described and produced as in example 4a, is
recrystallized. For this purpose, the product from example 4a is
dissolved in deionized water at boiling and then slowly cooled and
crystallized, to convert it back into the solid form. It is
subsequently washed with methanol and dried in a vacuum drying oven
at 50.degree. C. and about 20 mbar. Table 4
[0229] Obtained accordingly is an
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide having two
endothermic peaks (1.sup.st at about 160.degree. C. and 2.sup.nd at
about 190.degree. C.) in the DSC. This product with the two peaks
in the DSC as per FIG. 3 and the XRPD spectrum as per FIG. 7
produces far-reaching matting in powder coatings, with a gloss of
30 scale divisions at a 60.degree. angle. Table 4.
Comparative Example 4c
[0230] A noninventive
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide with the
DSC as per FIG. 4 was prepared.
[0231] This product shows only one endothermic peak in the DSC, at
about 190.degree. C., as per FIG. 4, and an XRPD spectrum as per
FIG. 6 and table 6. The powder coating material produced from it
does not exhibit far-reaching matting, but instead has a gloss of
95 scale divisions at the 60 degree angle. Table 4
Example 4d
[0232] An N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide
of the formula XIIA with the product data 4d is prepared in the
same way as described in example 1 in an extruder (Werner and
Pfleiderer ZSK 30, 32 d). Table 4
[0233] This product thus produced is run onto a cooling belt and
collected. This material is then conditioned thermally under
reduced pressure in a drying cabinet at 80.degree. C. for 24 hours,
and the resulting product is subsequently comminuted.
[0234] This product produces far-reaching matting in powder coating
materials, with a gloss of 40 scale divisions at the 60.degree.
angle. Table 4
TABLE-US-00020 TABLE 4 End products from continuous preparation,
examples 4a-4b, and their characterization by GC analysis.sup.1)
Product examples 4a 4b 4d Starting material -- SK 988 Preparation
Extruder setting as Dissolve 4a in deionized Extruder setting as
described in water described in example 1 example 1 cool slowly
thermal conditioning crystallize 24 h 80.degree. C. vacuum wash
with methanol dry under vacuum .sup.1)DEA fraction % by mass 2.17
0.11 1.2 .sup.1)trans-N,N,N',N'-Tetrakis(2- % by mass 84.25 93.72
91.3 hydroxyethyl)cyclohexyl-1,4-diamide
.sup.1)cis-N,N,N',N'-Tetrakis(2- % by mass 1.60 0.11 0.66
hydroxyethyl)cyclohexyl-1,4-diamide .SIGMA. N,N,N',N'-Tetrakis(2- %
by mass 85.85 93.83 91.96 hydroxyethyl)cyclohexyl-1,4-diamide Ratio
of .sup.1)trans-N,N,N',N'-tetrakis(2- mol % 98.1 99.9 99.3
hydroxyethyl)cyclohexyl-1,4-diamide to
.sup.1)cis-N,N,N',N'-tetrakis(2- mol % 1.9 0.1 0.7
hydroxyethyl)cyclohexyl-1,4-diamide OH number mg KOH/g 641 625 Base
number -- 24 1.1 DSC: 1.sup.st endo. peak - .DELTA. H .degree. C. -
J/g 162-61 158-50 DSC: 2.sup.nd endo. peak - .DELTA. H .degree. C.
- J/g 200-128 188-115 .sup.1Analytical values by GC. GC after
silylation with Silyl 991 (BSTFA-TMCS 99: 1) from Macherey and
Nagel order No. 701.490.150. Silylation: 1 ml Silyl 991, 1 ml
pyridine, 35 mg reaction product, 35 mg C-18 hydrocarbon as
internal standard, heat for 30 minutes at 80.degree. C. in a closed
ampoule. Powder coating data PC experiment number 4b 4d HAA
crosslinker % by mass 3.00 3.00 CRYLCOAT .RTM. 2617-3 % by mass
60.70 60.70 KRONOS .RTM. 2160 % by mass 35.00 35.00 RESIFLOW .RTM.
PV 88 % by mass 1.00 1.00 Benzoin % by mass 0.30 0.30 Total % by
mass 100.00 100.00 Curing Min @.degree. C. 30 @ 200 30 @ 200 Film
thickness .mu.m 52-55 58-68 Gloss at 60.degree. Sc. div. 29-30 40
OH number: DIN 53240 Base number: DIN 53176 End products from
preparation of comparative examples 4c and characterization by GC
analysis.sup.1) and powder coating material Comparative example 4c
Starting material Preparation - allow to cool at RT .sup.1)DEA % by
mass 2.87 .sup.1)trans-N,N,N',N'-tetrakis(2- % by mass 64.11
hydroxyethyl)cyclohexyl-1,4- diamide
.sup.1)cis-N,N,N',N'-tetrakis(2- % by mass 15.84
hydroxyethyl)cyclohexyl-1,4- diamide .SIGMA. N,N,N',N'-tetrakis(2-
% by mass 79.95 hydroxyethyl)cyclohexyl-1,4- diamide Ratio of
.sup.1)trans-N,N,N',N'- mol % 80.19
tetrakis(2-hydroxyethyl)cyclohexyl- 1,4-diamide to
.sup.1)cis-N,N,N',N'-tetrakis(2- mol % 19.81
hydroxyethyl)cyclohexyl-1,4- diamide OH number mg KOH/g sample --
Base number -- -- DSC: 1.sup.st endo. peak - .DELTA.H .degree. C. -
J/g DSC: 2.sup.nd endo. peak - .DELTA.H .degree. C. - J/g 171-87
Powder coating data PC experiment number 4c HAA crosslinker % by
mass 3.00 CRYLCOAT .RTM. 2617-3 % by mass 60.70 KRONOS .RTM. 2160 %
by mass 35.00 RESIFLOW .RTM. PV 88 % by mass 1.00 Benzoin % by mass
0.30 Total % by mass 100.00 Curing min @.degree. C. 30 @ 200 Film
thickness .mu.m 65-78 Gloss at 60.degree. Sc. div. 95
Example 5
[0235] A .beta.-hydroxyalkylamide of the formula XIIA was prepared
as in example 3a. From it a single crystal was grown. The inventive
of the formula XIIA was investigated by x-ray structural analysis
of a single crystal. Comprehensive details relating to the
measurement are compiled in annex 1.
Annex 1
Single-Crystal X-Ray Structural Analysis
[0236] Analytical method: Single Crystal X-ray Structure Analysis
"2012-0573602-06D"
Report: WHC 11/11 EKS
[0237] Receipt of sample: 2011-02-22 Report date: 2011-02-25
Objective: Determination of single crystal structure. Compound:
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide, formula
XIIA
##STR00023##
Crystallization: by the chemist. Crystal dimensions: colorless
block, 0.50.times.0.40.times.0.40 mm.sup.3 Code: vesta Comments:
The asymmetric unit comprises half a molecule.
Experimental Details
[0238] The single crystal structure was determined using an
instrument from Oxfor Diffraction which was equipped with a CCD
detector (Ruby model), a conventional x-ray tube with
Cu.sub.K.alpha. radiation, Osmic mirror as monochromator, and a
low-temperature unit of the Cryojet type (T=100 K). Data collection
was carried out in phi and omega scans. Data collection and
reduction took place using Crysalis (Oxford Diffraction 2007).
[0239] Structural resolution and refinement took place using
SHELXTL (V. 6.10, Sheldrick, University of Gottingen, 2000). All
non-hydrogen atoms were refined anisotropically. The hydrogen atoms
were refined as riding groups.
Tables
TABLE-US-00021 [0240] TABLE A Crystal data and data relating to
structural refinement for vesta. Identification code vesta
Empirical formula C16H30N2O6 Formula weight 346.42 Temperature 100
K Wavelength 1.54178 .ANG. Crystal system Orthorhombic Space group
Pbca Unit cell a = 10.06350(10) .ANG. = 90.degree.. b =
11.85290(10) .ANG. = 90.degree.. c = 14.6275(2) .ANG. = 90.degree..
Volume 1744.79(3) .ANG..sup.3 Z 4 Density (calculated) 1.319
Mg/m.sup.3 Absorption coefficient 0.832 mm.sup.-1 F(000) 752
Crystal dimensions 0.50 .times. 0.40 .times. 0.40 mm.sup.3 Theta
range for data collection 6.05 to 65.68.degree.. Index range -11
.ltoreq. h .ltoreq. 10, -12 .ltoreq. k .ltoreq. 14, -14 .ltoreq. l
.ltoreq. 17 Number of reflections collected 9191
Symmetry-independent reflections 1482 [R(int) = 0.0345]
Completeness to theta = 65.68.degree. 98.5% Correction for
absorption Crysalis Refinement Full-matrix least-squares on F.sup.2
Data/restraints/parameters 1482/0/111 Goodness-of-fit on F.sup.2
1.065 Final R values [I > 2sigma(I)] R1 = 0.0316, wR2 = 0.0792 R
values (all data) R1 = 0.0358, wR2 = 0.0817 Largest difference
peaks 0.199 and -0.189 e .ANG..sup.-3
TABLE-US-00022 TABLE B Bond lengths [.ANG.] and angles [.degree.]
for vesta. O(1)--C(4) 1.2478(15) O(2)--C(6) 1.4221(15) O(3)--C(8)
1.4205(16) N(1)--C(4) 1.3479(16) N(1)--C(5) 1.4741(15) N(1)--C(7)
1.4727(15) C(1)--C(3)#1 1.5291(17) C(1)--C(2) 1.5398(16) C(2)--C(4)
1.5189(17) C(2)--C(3) 1.5405(16) C(3)--C(1)#1 1.5291(17) C(5)--C(6)
1.5182(16) C(7)--C(8) 1.5159(17) C(4)--N(1)--C(5) 124.59(10)
C(4)--N(1)--C(7) 117.87(10) C(5)--N(1)--C(7) 117.54(9)
C(3)#1--C(1)--C(2) 110.62(10) C(4)--C(2)--C(1) 111.04(10)
C(4)--C(2)--C(3) 108.67(10) C(1)--C(2)--C(3) 110.09(10)
C(1)#1--C(3)--C(2) 111.18(10) O(1)--C(4)--N(1) 119.97(11)
O(1)--C(4)--C(2) 120.15(10) N(1)--C(4)--C(2) 119.84(10)
N(1)--C(5)--C(6) 113.66(9) O(2)--C(6)--C(5) 110.97(10)
N(1)--C(7)--C(8) 113.52(10) O(3)--C(8)--C(7) 113.31(10) Symmetry
operations for generating equivalent atoms: #1 -x + 1, -y + 1,
-z
TABLE-US-00023 TABLE C Torsional angles [.degree.] for vesta.
C(3)#1--C(1)--C(2)--C(4) 177.11(9) C(3)#1--C(1)--C(2)--C(3)
56.72(14) C(4)--C(2)--C(3)--C(1)#1 -178.85(9)
C(1)--C(2)--C(3)--C(1)#1 -57.04(14) C(5)--N(1)--C(4)--O(1)
176.19(10) C(7)--N(1)--C(4)--O(1) -3.65(16) C(5)--N(1)--C(4)--C(2)
-6.21(16) C(7)--N(1)--C(4)--C(2) 173.95(10) C(1)--C(2)--C(4)--O(1)
-54.62(14) C(3)--C(2)--C(4)--O(1) 66.61(14) C(1)--C(2)--C(4)--N(1)
127.78(11) C(3)--C(2)--C(4)--N(1) -110.98(12)
C(4)--N(1)--C(5)--C(6) 80.57(13) C(7)--N(1)--C(5)--C(6) -99.58(12)
N(1)--C(5)--C(6)--O(2) 61.92(13) C(4)--N(1)--C(7)--C(8) 86.25(13)
C(5)--N(1)--C(7)--C(8) -93.60(12) N(1)--C(7)--C(8)--O(3) 73.97(13)
Symmetry operations for generating equivalent atoms: #1 -x + 1, -y
+ 1, -z
FIG. 11:
[0241] Calculated powder diffractogram based on the single crystal
structural determination of
N,N,N',N'-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide (vesta
sample)
* * * * *