U.S. patent application number 12/936621 was filed with the patent office on 2011-02-03 for paste resin for universal pigment paste.
Invention is credited to Gerald Hobisch, Peter Morre, Thomas Schonbacher, Edmund Urbano.
Application Number | 20110028636 12/936621 |
Document ID | / |
Family ID | 39832561 |
Filed Date | 2011-02-03 |
United States Patent
Application |
20110028636 |
Kind Code |
A1 |
Hobisch; Gerald ; et
al. |
February 3, 2011 |
PASTE RESIN FOR UNIVERSAL PIGMENT PASTE
Abstract
The invention relates to a paste resin AB which is a mixture of
a water-reducible alkyd resins B and a basic acrylic copolymer
resin A comprising at least one amino group-containing vinyl type
monomer A1, and a method of use thereof for formulating both
water-borne and solvent-borne tinted paints with a wide variety of
pigments.
Inventors: |
Hobisch; Gerald; (Graz,
AT) ; Morre; Peter; (Graz, AT) ; Schonbacher;
Thomas; (Kalsdorf, AT) ; Urbano; Edmund;
(Graz, AT) |
Correspondence
Address: |
CONNOLLY BOVE LODGE & HUTZ, LLP
P O BOX 2207
WILMINGTON
DE
19899
US
|
Family ID: |
39832561 |
Appl. No.: |
12/936621 |
Filed: |
April 15, 2009 |
PCT Filed: |
April 15, 2009 |
PCT NO: |
PCT/EP09/54481 |
371 Date: |
October 21, 2010 |
Current U.S.
Class: |
524/513 ;
525/165 |
Current CPC
Class: |
C08L 67/08 20130101;
C09D 167/08 20130101; C08L 33/14 20130101; C09D 167/08 20130101;
C08G 18/672 20130101; C08L 67/08 20130101; C08G 18/283 20130101;
C08L 33/08 20130101; C08L 33/08 20130101; C08L 67/08 20130101; C08L
33/14 20130101; C09D 17/00 20130101; C09D 133/14 20130101; C08L
33/14 20130101; C09D 133/14 20130101; C08L 67/08 20130101; C09D
133/14 20130101; C08L 2666/02 20130101; C08L 2666/02 20130101; C08L
2666/18 20130101; C08L 2666/04 20130101; C08L 33/00 20130101; C08L
2666/18 20130101; C08L 2666/04 20130101 |
Class at
Publication: |
524/513 ;
525/165 |
International
Class: |
C09D 133/08 20060101
C09D133/08; C08L 67/02 20060101 C08L067/02 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 16, 2008 |
EP |
08007450.3 |
Claims
1. A paste resin AB which is a mixture of a water-reducible alkyd
resin B and a basic acrylic copolymer resin A, wherein the basic
acrylic copolymer resin A is a copolymer of at least three classes
of vinylic monomers having each at least one copolymerisable
olefinic unsaturation, the vinylic monomers comprising at least one
amino group-containing vinyl type monomer A1, at least one monomer
A2 selected from the group consisting of linear or branched
alkyl(meth)acrylates having from 1 to 13 carbon atoms in the alkyl
group, and at least one hydrophilic vinyl monomer A3 having a
moiety derived from a polyether glycol which is a polyethylene
glycol or a mixed ether of ethylene and propylene glycol having a
mass fraction of at least 60% of oxyethylene groups in the total
mass of oxyalkylene groups, where one of the hydroxyl groups of the
polyetherglycol is converted to an ether group, and the other
hydroxyl group is consumed by esterification with an olefinically
unsaturated monocarboxylic acid, or by etherification with an
olefinically unsaturated alcohol, or by urethane formation via
reaction with an adduct of a hydroxyalkyl(meth)acrylate and a
diisocyanate.
2. The paste resin AB of claim 1 wherein the water-reducible alkyd
resin B has an acid number of from 0.2 mg/g to 5 mg/g.
3. The paste resin AB of claim 1 wherein the water-reducible alkyd
resin B is based on a condensation product of an alkyd resin Ba and
an adduct Bb of a C.sub.1- to C.sub.4-monoalkyl ether Bb1 of a
polyoxyethylene glycol or of a C.sub.1- to C.sub.4-monoalkyl ether
Bb2 of a mixed ether of ethylene and propylene glycol, or mixtures
thereof, and an anhydride Bb3 of a cycloaliphatic dicarboxylic
acid, and wherein in the water-reducible alkyd resin B, the ratio
of the sum of the amounts of substance of Bb1 and Bb2 to the amount
of substance of Bb3 being from 0.95 mol: 1.05 mol to 1.05 mol: 0.95
mol.
4. The paste resin AB of claim 1 wherein the mass fraction of
monomers A1 is from 15% to 40%, the mass fraction of monomers A2 is
from 15% to 45%, and the mass fraction of monomers A3 is from 30%
to 60%.
5. The paste resin AB of claim 1 wherein the monomer A3 is a
reaction product of polyethylene glycol monoether, toluylene
diisocyanate and hydroxyethyl methacrylate.
6. The paste resin AB of claim 3 wherein the alkyd resin Ba is made
by co-condensation of one or more polyols Ba1 having two or more
hydroxyl groups per molecule, one or more polybasic acids Ba2, and
one or more fatty acids Ba3 which may be replaced, or mixed with,
one or more triglyceride oils Ba4.
7. The paste resin AB of claim 1 wherein the constituents A and B
are mixed in a mass ratio of from 45% to 75% of A and from 55% to
25% of B.
8. A pigment paste comprising the paste resin AB of claim 1 and at
least one pigment selected from the group consisting of inorganic
pigments and organic pigments.
9. A method of use of the paste resin of claim 1 comprising mixing
the said paste resin AB with at least one pigment, homogenising the
mixture under shear to form a pigment paste, and mixing the said
pigment paste with an unpigmented or white pigmented paint
comprising an organic paint binder.
10. The method of claim 9 wherein the said paint binder is selected
from the group consisting of alkyd resins, acrylic resin, acrylic
modified alkyd resins, urethane alkyds, and urethane modified
acrylic resins.
11. The method of claim 9 wherein the paint is a water-borne
paint.
12. The method of claim 9 wherein the paint is a solvent-borne
paint.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a paste resin for a
universal pigment paste for tinting of coloured paints.
BACKGROUND OF THE INVENTION
[0002] In the paint industry, stock control and logistics are
rationalised by using colour mixing systems. In such systems, a
paint colour selected for a customer is produced by selecting a
base paint from a range of available base paints and adding to the
selected base paint one or more pigment pastes which are intimate
mixtures of one or more pigments with paste resins which latter
having good dispersing properties. Such systems have been widely
used in the field of decorative coatings, as disclosed, e. g., in
EP 0 311 209 A1.
[0003] Examples of pigment pastes for paint tinting systems are
disclosed in WO 91/06607 A1 (water-borne polyesters), WO 99/49963
A1 (solvent-borne polyesters), and EP 0 458 479 A2 (acrylic
modified polyesters for solvent-borne paints). In addition to at
least one pigment, pigment pastes typically include special resins,
solvents, and usually also additives. Pigments for various colours
vary considerably in chemical nature, from simple inorganic
elements such as carbon in the form of channel black or lamp black,
to inorganic oxides (such as iron oxides, copper, cobalt, chromium
and lead based pigments) and organic pigments (such as azo
pigments, phthalocyanine pigments, and polycyclic aromatic pigments
such as perylene, anthraquinone and quinacridone pigments). For
each pigment, a compatible resin needs to be used. This resin
needs, in turn, to be compatible with the binder system of the base
paints and with the resins used in other pigment pastes as well,
since for most colours, the addition of more than one pigment paste
is required. The resin should also be able to disperse a sufficient
amount of the pigment. Up to now it has not been possible to use
tinting systems compatible with both solvent borne paints and water
borne paints, and which are also compatible with the usual range of
binder resins.
SUMMARY OF THE INVENTION
[0004] The object of the invention is therefore to provide a
pigment paste comprising a resin ("paste resin") which is
compatible with most types of pigments, as well as most binder
resins, be they solvent-borne or water-borne. The paste resin
should have sufficient dispersing and wetting power to disperse
various pigments based on different raw materials such as those
mentioned supra.
[0005] This object has been achieved by providing a paste resin
which is a mixture of a water-reducible alkyd resin B and a basic
acrylic copolymer resin A, wherein the basic acrylic copolymer
resin A is a copolymer of at least three classes of vinylic
monomers having each at least one copolymerisable olefinic
unsaturation, the vinylic monomers comprising at least one amino
group-containing vinyl type monomer A1, at least one monomer A2
selected from the group consisting of linear or branched
alkyl(meth)acrylates having from 1 to 13 carbon atoms in the alkyl
group, and at least one hydrophilic vinyl monomer A3 having a
moiety derived from a polyether glycol which is a polyethylene
glycol or a mixed ether of ethylene and propylene glycol having a
mass fraction of at least 60% of oxyethylene groups in the total
mass of oxyalkylene groups, where one of the hydroxyl groups of the
polyetherglycol is converted to an ether group, and the other
hydroxyl group is consumed by esterification with an olefinically
unsaturated monocarboxylic acid, or by etherification with an
olefinically unsaturated alcohol, or by urethane formation via
reaction with an adduct of a hydroxyalkyl(meth)acrylate and a
diisocyanate.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0006] The water-reducible alkyd resin B preferably has an acid
number of from 0.2 mg/g to 5 mg/g, particularly preferred from 0.5
mg/g to 3 mg/g, and preferably a dynamic viscosity, measured in a
50% strength dispersion in water at a temperature of 23.degree. C.,
and a shear stress of 25 s.sup.-1, according to DIN EN ISO 3219, of
from 5 mPas to 25 mPas.
[0007] The alkyd resin B is based on a condensation product of an
alkyd resin Ba and an adduct Bb of a C.sub.1- to C.sub.4-monoalkyl
ether Bb1 of a polyoxyethylene glycol or of a C.sub.1- to
C.sub.4-monoalkyl ether Bb2 of a mixed ether of ethylene and
propylene glycol, or mixtures thereof, and an anhydride Bb3 of a
cycloaliphatic dicarboxylic acid, the ratio of the sum of the
amounts of substance of Bb1 and Bb2 to the amount of substance of
Bb3 preferably being from 0.95 mol: 1.05 mol to 1.05 mol: 0.95
mol.
[0008] The water-reducible alkyd resin B is preferably made by
reaction of Ba and Bb under esterification conditions, i. e. under
removal of water preferably in the presence of an entraining agent
such as xylene via azeotropic distillation and recycling of the
entraining agent. It is also possible to use usual esterification
catalysts. Esterification at a temperature of preferably from
170.degree. C. to 260.degree. C. is continued until a sample drawn
has an acid number of 3 mg/g or below.
[0009] A coating composition is disclosed in U.S. Pat. No.
3,878,140 comprising a mixture of (A) a blend of an acrylic
copolymer (A1) made from methyl methacrylate and an alkyl acrylate
or an alkyl methacrylate having each from 2 to 12 carbon atoms in
the alkyl group, an second acrylic copolymer (A2) made from methyl
methacrylate and an adhesion promoting monomer such as
3-(2-methacryl-oxyethyl)-2,2-spiro-cyclohexyl oxazolidine, and a
plasticiser (A3) which is either a phthalate ester or an alkyd
resin, and a pigmented acrylic composition (B) comprising a
copolymer (B1) which is polymethyl methacrylate or a copolymer of
methyl methacrylate or a mixture of these polymers, and cellulose
acetobutyrate (B2) and an organic plasticiser (B3). The alkyd resin
plasticiser disclosed herein is a reaction product of nondrying oil
fatty acids, a polyhydric alcohol, and a dicarboxylic acid or its
anhydride.
[0010] An antifouling agent has been known from U.S. published
patent application 2005/0 096 407 A1 which is a combination of a
biocidally active material and a nonaqueous dispersion of a polymer
binder which latter comprises at least one alkyd resin having a
mass fraction of non-volatile matter of at least 90%, a z-average
molar mass of between 10 kg/mol and 250 kg/mol as dispersing medium
for polymerisation of an acrylic resin, with a mass ratio of alkyd
to acrylic portion of from 50:50 to 30:70. The alkyd resin employed
may be a long oil or medium oil alkyd based on soya or linseed
fatty acid, as also exemplified in Ex. 1A (soybean oil,
trimellithic anhydride, and trimethylol ethane) and 1B (soya oil
fatty acid, pentaerythritol, crotonic and isophthalic acids).
[0011] The acid number is defined as usual according to DIN EN ISO
3682 as the ratio of that mass m(KOH) of potassium hydroxide which
is needed to neutralise a sample having a mass m(Sample) to the
said mass m(Sample), in the case of a solution or dispersion as a
sample, m(Sample) is replaced by the mass m(solids) of solid matter
in the said solution or dispersion, the usual unit being
"mg/g".
[0012] The alkyd resin Ba is made in the usual way, by
co-condensation of one or more polyols Ba1 having two or more
hydroxyl groups per molecule, one or more polybasic acids (which
have two or more acidic groups per molecule) Ba2, and one or more
fatty acids Ba3 which may be replaced, or mixed with, one or more
triglyceride oils Ba4. Optionally, the condensation mixture may
also contain one or more monobasic acids Ba5. Preferably at least
one of the fatty acids Ba3 has at least one olefinic unsaturation
per molecule. Preferably, at least one of the triglyceride oils Ba4
comprises at least one residue derived from a fatty acid having at
least one olefinic unsaturation in its molecule.
[0013] The polyols Ba1 are aliphatic linear or branched-chain
hydroxyl compounds having from two to six hydroxyl groups per
molecule, preferably up to four hydroxyl groups per molecule, such
as ethylene glycol, 1,2- and 1,3-propylene glycol, 1,2- and
1,4-butanediol, glycerol, trimethylol propane, trimethylol ethane,
erythritol, threitol, pentaerythritol, ditrimethylol propane,
ditrimethylol ethane, sorbitol, and mannitol.
[0014] The polybasic acids Ba2 may be aliphatic linear, branched or
cyclic, or aromatic, having from two to four acid groups, and
preferably from 3 to 20 carbon atoms, and may preferably be
selected from the group consisting of phthalic acid, trimellithic
acid, tetrahydrophthalic acid, adipic acid, malonic acid,
cyclohexane dicarboxylic acids, isophthalic and terephthalic acids,
and benzophenone tetracarboxylic acid.
[0015] The fatty acids Ba3 are preferably at least monoolefinically
unsaturated aliphatic monocarboxylic acids having preferably from 4
to 24 carbon atoms. Preferred are lauroleic, myristoleic,
palmitoleic, oleic, gadolic, erucic, ricinoleic, linoleic, and
linolenic acids, as well as mixtures of these, particularly the
naturally occurring mixtures such as soy bean oil fatty acid,
linseed oil fatty acid, sunflower oil fatty acid, safflower oil
fatty acid, rubber seed oil fatty acid, and tall oil fatty
acid.
[0016] The triglyceride oils Ba4 are oils preferably having an
iodine number of from 120 cg/g to 200 cg/g, particularly preferably
soy bean oil, linseed oil, sunflower oil, safflower oil, rubber
seed oil, and tall oil.
[0017] The monobasic acids Ba5 are preferably aromatic
monocarboxylic acids such as benzoic acid or alkyl-substituted
benzoic acids, cycloaliphatic monocarboxylic acids, in particular
the so-called resin acids, aliphatic branched carboxylic acids,
such as isononanoic acid, 2-ethylhexanoic acid, or .RTM.Versatic
acid, a mixture of alpha-branched decanoic acids.
[0018] Preferably, the alkyd resins Ba have an acid number of less
than 5 mg/g, particularly preferred from 0.1 mg/g to 4 mg/g, and
especially preferred from 0.2 mg/g to 3.5 mg/g. Their hydroxyl
number is preferably from 30 mg/g to 100 mg/g, particularly
preferred from 40 mg/g to 90 mg/g, and especially preferred from 60
mg/g to 85 mg/g.
[0019] The adduct Bb is the reaction product of a hydroxyl
group-containing monoalkyl ether Bb1 selected from the group
consisting of C.sub.1- to C.sub.4-monoalkyl ethers Bb11 of a
polyoxyethylene glycol, a C.sub.1- to C.sub.4-monoalkyl ether Bb12
of a mixed ether of ethylene and propylene glycol, and of mixtures
thereof, and an anhydride Bb2 of a cycloaliphatic dicarboxylic
acid, the ratio of the sum of the amounts of substance of Bb11 and
Bb12 to the amount of substance of Bb2 preferably being from 0.95
mol: 1.05 mol to 1.05 mol: 0.95 mol. The adduct Bb preferably has
an acid number of from 5 mg/g to 60 mg/g, particularly preferred of
from 10 mg/g to 45 mg/g, and especially preferred, of from 15 mg/g
to 40 mg/g.
[0020] The hydroxy functional ethers Bb11 are preferably methyl,
ethyl, n-propyl and n-butyl monoethers of polyethylene glycol,
wherein the polyethylene glycol has a weight average molar mass of
preferably from 500 g/mol to 4000 g/mol, particularly preferred
from 750 g/mol to 3000 g/mol. The average number of hydroxyl groups
per molecule is preferably from 0.8 to 1.2, particularly preferred
from 0.9 to 1.1. Especially preferred are polyethylene glycols
partially etherified with ethanol, and having a molar mass of from
1000 g/mol to 2000 g/mol.
[0021] The hydroxy functional ethers Bb12 are preferably methyl,
ethyl, n-propyl and n-butyl monoethers of a mixed ether of ethylene
and 1,2-propylene glycols, wherein the mass fraction of oxyethylene
groups is from 10% to 85%, and the mass fraction of oxypropylene
groups is from 90% to 15%, calculated as the ratio of the mass of
oxyalkylene groups having two or three carbon atoms, respectively,
and the sum of the masses of all oxyalkylene groups in the mixed
ether Bb12, and have a weight average molar mass of preferably from
500 g/mol to 10 000 g/mol, particularly preferred from 1000 g/mol
to 8000 g/mol. The average number of hydroxyl groups per molecule
is preferably from 0.8 to 1.2, particularly preferred from 0.9 to
1.1.
[0022] The anhydride Bb2 of a cycloaliphatic dicarboxylic acid can
preferably have from 8 to 12 carbon atoms and is preferably
selected from the group consisting of tetrahydrophthalic anhydride,
hexahydrophthalic anhydride, and their homologues such as
methyltetrahydrophthalic anhydride or butyl tetrahydrophthalic
anhydride. It has been found, surprisingly, that cyclic anhydrides
of non-cyclic dicarboxylic acids such as maleic or succinic
anhydride do not work well in the context of the present invention
as they impair the pigment compatibility.
[0023] The basic acrylic copolymer resin A is a copolymer of at
least three classes of vinylic monomers having each at least one
copolymerisable olefinic unsaturation. It comprises at least one
amino group-containing vinyl type monomer A1 which preferably has
at least one amino group which is particularly preferably a
tertiary amino group. Particularly useful amino-functional vinyl
monomers are esters of tertiary aminoalcohols with acrylic or
methacrylic acid, such as dimethyl aminoethyl (meth)acrylate,
dimethyl aminopropyl (meth)acrylate, and amides of monotertiary
monoprimary diamines such as dimethylaminoethyl (meth)acrylamide,
3-N,N-dimethylaminopropyl (meth)acrylamide, and the corresponding
diethylamino compounds. Further monomers A2 are linear or branched
alkyl(meth)acrylates having from 1 to 13 carbon atoms in the alkyl
group, such methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl
(meth)acrylate, isobutyl (meth)acrylate and 2-ethylhexyl
(meth)acrylate. Further monomers present in the polymerisation
reaction leading to A are hydrophilic vinyl monomers A3 having a
moiety derived from polyethylene glycol or a mixed ether of
ethylene and propylene glycol having a mass fraction of at least
60% of oxyethylene groups in the total mass of oxyalkylene groups,
the polyether fragment having a molar mass of preferably from 200
g/mol to 5000 g/mol, particularly preferably from 500 g/mol to 1500
g/mol, where one of the hydroxyl groups of the polyetherglycol is
converted to an ether group, preferably a methyl, ethyl or butyl
ether group, and the other hydroxyl group is consumed by
esterification with (meth)acrylic acid or other olefinically
unsaturated monocarboxylic acids, or by etherification with an
olefinically unsaturated alcohol such as allyl or methallyl
alcohols, or by urethane formation via reaction with an adduct of a
hydroxyalkyl(meth)acrylate and a diisocyanate. It is particularly
preferred to use monomers A3 which are adducts of hydroxyethyl
(meth)acrylate, an aromatic isocyanate such as toluylene
diisocyanate or bis(4-isocyanatophenyl)methane, and a polyethylene
glycol of a molar mass from 200 g/mol to 5000 g/mol, esters of the
said polyethylene glycol with (meth)acrylic acid, and ethers of the
said polyethylene glycol with (meth)allyl alcohol. Mixtures of two
or more monomers A3 can also be used. The mass fraction of the
monomers A1, A2 and A3 are preferably from 15% to 40%, from 15% to
45%, and from 30% to 60%, respectively, particularly preferably
from 20% to 35%, from 20% to 40%, and from 35% to 55%,
respectively, and especially preferably from 25% to 30%, from 25%
to 35%, and from 40% to 50%, respectively. Polymerisation is
conducted as customary in solution, using alcohols such as
isopropanol, or esters such as butyl acetate as solvents, and azo
or peroxo catalysts such as azobis-isobutyronitrile, tert.-amyl
peroctoate or tert.-amyl peroxide.
[0024] It is also possible to copolymerise with the monomers A1 to
A3 any further monomers A4 which are also of the vinyl type, i. e.
they also have at least one copolymerisable olefinically
unsaturated group in their molecules. These monomers A4 may also be
used in mixtures of two or more of these monomers A4. Such monomers
are preferably styrene, any of the isomers of alkyl styrenes,
particularly methyl styrenes ("vinyl toluene"), vinyl naphthalene,
alkyl esters of olefinically unsaturated carboxylic acids, dialkyl
esters of olefinically unsaturated dicarboxylic acids, hydroxyalkyl
esters of the same acids, unsaturated amides and nitriles derived
from such acids, alkyl vinyl ethers, and alkyl vinyl ketones.
Acidic vinyl type monomers, such as acrylic or methacrylic acids,
are, of course, less preferred.
[0025] The constituents A and B are mixed in a mass ratio of from
45% to 75% of A and from 55% to 25% of B, preferably from 50% to
70% of A and from 50% to 30% of B, particularly preferably from 55%
to 65% of A and from 45% to 35% of B.
[0026] Pigments include inorganic as well as organic pigments.
Examples of inorganic pigments include titanium dioxide, zinc
oxide, carbon black, iron oxides, bismuth vanadates, raw and burnt
sienna or umber, chromium oxide green, cadmium pigments, chromium
pigments, etc. Examples of organic pigments include
phthalocyanines, quinacridones, quinophthalones, anthraquinones,
isoindolines, pyranthrones, indanthrones, derivatives of dioxazine,
diketopyrrolopyrroles, azo-compounds, etc. Optionally, filler
pigments may be added, such as clay, silica, talc, mica,
wollastonite, wood flour, and the like.
[0027] Pigment paste may be produced from the paste resin AB and at
least one pigment selected from the group consisting of inorganic
pigments and organic pigments. This is preferably done by mixing
the paste resin AB with at least one pigment, homogenising the
mixture under shear to form a pigment paste, and mixing the said
pigment paste with an unpigmented or white pigmented paint
comprising an organic paint binder. The organic paint binder is
preferably selected from the group consisting of alkyd resins,
acrylic resin, acrylic modified alkyd resins, urethane alkyds, and
urethane modified acrylic resins. However, also other paint binders
such as polyurethane resins can be used, alone, or in mixture with
one or more of those mentioned supra. The pigment paste thus
produced can be used in combination with a water-borne paint or
with a solvent-borne paint, and offers in all combinations coloured
or tinted paints with high gloss and good colour strength.
[0028] High pigment contents can be realised in the pigment pastes
according to the present invention without the use of high amounts
of solvent. If organic pigments are used, the pigment content
suitably ranges in mass fractions of from 5% to 45%, preferably
from 25% to 40%. If inorganic pigments are used, the pigment
content should preferably be more than a mass fraction of 10% by
weight or, more preferably, even more than 60%. If translucent
pigments, e. g. translucent iron oxides, are used, the pigment
content can be over a mass fraction of 5%, preferably over 20%, or
even 30% or more.
[0029] If so desired, the pigment pastes according to the invention
may also comprise anti-foaming agents, matting agents,
anti-settling agents, anti-skinning agents, such as methyl ethyl
ketoxime, and/or other suitable additives.
[0030] The invention is also directed to a method for tinting a
paint by selecting a base paint from a set of base paints and
subsequently mixing the base paint with one or more of the
above-described pigment pastes. Although in theory it is possible
to mix all colours using a single clear base paint, generally also
white base paints are used in tinting systems to obtain colours
with sufficient hiding power.
[0031] Different grades of white pigmented base paints may be used,
if so desired.
[0032] Generally, also a limited number of pre-tinted base paints
are used to enhance the scope of the miscible colours with
sufficient hiding power. Separate base paints for high-gloss, or
satin gloss paints may also be used, if so desired.
[0033] Pigment pastes according to the present invention are
particularly useful because they can be used with a wide variety of
paint binder resins, such as water-borne air drying alkyd resins,
acrylic resins, and polyurethane resins, as well as solvent borne
alkyd resins or acrylic resins. They lead to paints with good gloss
and excellent pigment dispersion as well as colour stability.
[0034] The following examples are meant to further illustrate the
invention without intending to limit to those features disclosed in
the examples.
[0035] In the examples, all amounts of contents with the unit "%"
are mass fractions unless indicated otherwise.
[0036] Viscosity was measured at 23.degree. C. at a shear rate of
100 s.sup.-1, in accordance with ISO 3219. Mass fraction of solids
("non-volatile content") was calculated in accordance with ISO
3251. Oil content is the mass fraction of oil(s) in the mass of the
alkyd resin, with the customary unit "%".
EXAMPLES
Example 1 Preparation of an alkyd resin B
[0037] An adduct was prepared by reacting 929 g of a monomethoxy
polyethylene glycol having a molar mass of 2000 g/mol with 71 g of
tetrahydrophthalic anhydride in the presence of 1 g of
triethylamine as catalyst to 150.degree. C. until a constant acid
number of 26.5 mg/g was reached.
[0038] After cooling, 644 g of this adduct were mixed with 409 g of
an alkyd resin having a hydroxyl number of 70 mg/g and an acid
number of less than 3 mg/g made from 160 g of sunflower oil, 72 g
of benzoic acid as chain stopper, 100 g of phthalic anhydride and
100 g of pentaerythritol. Xylene was added thereto in the amount of
10% of the mass of the resin mixture, the resulting mixture was
heated to 220.degree. C., and water was completely separated,
whereafter the xylene was distilled off. The remaining product has
an acid number of less than 2.5 mg/g. The dynamic viscosity of the
resin was 9.5 Pas, measured on a 50% strength aqueous solution.
This viscosity did not change during storage at 40.degree. C.
during two weeks.
Example 2 Preparation of an acrylic copolymer A
[0039] A mixture of 270 g of dimethylaminoethyl methacrylate, 50 g
of butylacrylate and 230 g of 2-ethylhexyl acrylate and 450 g of an
adduct prepared by reacting 1 mol each of hydroxyethyl
methacrylate, toluylene diisocyanate and dried polyethylene glycol
monomethyl ether of a molar mass of 750 g/mol were added,
simultaneously with 20 g tert.-amylperoctoate dissolved in 200 g of
isopropanol over a period of 5 hours to 330 g of isopropanol at
reflux condition and stirring under a nitrogen blanket. The mixture
was stirred for 1 hour after the addition was complete, and then,
further 20 g of catalyst solution were added. When the reaction had
ceased and the residual monomer concentration was below 0.3%, the
solvent was removed by distillation at approximately 110.degree. C.
under reduced pressure. The reaction vessel was then flushed with
nitrogen, and the reaction mass was allowed to cool to ambient
temperature.
Example 3 Preparation of a paste resin
[0040] 600 g of the alkyd resin of Example 1 and 400 g of the
acrylic resin of Example 2 were mixed after charging both resins
into a resin kettle and stirring at 80.degree. C. for 1 hour until
a homogeneous mixture was obtained. The heating was the switched
off, while stirring was continued, and 1222 g of water were then
added over a period of 30 minutes whereafter the kettle was allowed
to cool to ambient temperature. A semi-viscous, clear solution of
the grinding resin having a mass fraction of solids of about 45%
was obtained.
Example 4 Formulation of white basic paints
[0041] 4.1 Solvent-Borne White Alkyd Paint
[0042] 303 g of a solvent-borne alkyd resin (.RTM.Vialkyd AS
6172/55 SD60, Cytec Surface Specialties Austria GmbH, an alkyd
resin based on soy bean oil having an oil content of 57%, dissolved
in .RTM.Shellsol D60, a mixture of C.sub.10- to C.sub.12-paraffins
and -naphthenes, having a low mass fraction--less than 0.1%--of
aromatics), further 67 g of .RTM.Shellsol D60, and 268 g of a white
titanium dioxide pigment (.RTM.Kronos 2190, Kronos Titan GmbH) were
mixed and ground on a bead mill at room temperature for 30 minutes,
and then let down with a mixture of a further 303 g of .RTM.Vialkyd
AS 6172/55 SD60, 6.7 g of an antiskinning agent (.RTM.Additol XL
297/100, based on an oxime, Cytec Surface Specialties Austria
GmbH), a siccative mixture of 16.8 g of each of .RTM.Octa-Soligen
Cobalt 1, .RTM.Octa-Soligen Calcium 2 and .RTM.Octa-Soligen
Zirconium 6 (metal octoate driers, Borchers GmbH, the number
indicates the mass fraction in % of metal octoate in the solution,
using as solvent .RTM.Shellsol D60), and 1.9 g of a flow and
levelling additive (.RTM.Additol VXL 4930, based on a polyether
modified silicone, Cytec Surface Specialties Austria GmbH). The
resulting white paint (approximately 1000 g) had a viscosity
measured as described supra of 542 mPas.
[0043] 4.2 Water-Borne White Alkyd Paint
[0044] 395 g of a water-borne alkyd resin (.RTM.Resydrol AY
586w/38WA, an acrylic modified alkyd resin, Cytec Surface
Specialties Austria GmbH), and 254 g of a white titanium dioxide
pigment (.RTM.Kronos 2059, hydrophilically treated, Kronos Titan
GmbH), 21.5 g of a combination siccative (.RTM.Additol VXW 4940, an
emulsion of siccatives based on Co, Ba, and Zr compounds, diluted
by to 50% strength with deionised water, Cytec Surface Specialties
Austria GmbH), 1.45 g of a defoamer (based on liquid hydrocarbons,
.RTM.Additol VXW 6211, Cytec Surface Specialties Austria GmbH) and
5.35 g of a flow and levelling additive (.RTM.Additol XW 329, based
on a polyether modified silicone, Cytec Surface Specialties Austria
GmbH) were mixed and ground on a bead mill at room temperature for
30 minutes, and then let down with a mixture of a further 268 g of
.RTM.Resydrol AY 586w/38WA, 5.35 g of .RTM.Additol XL 297 (v. s.),
24.4 g of deionised water, and 7.3 g of an 25% strength aqueous
ammonia solution. The resulting white paint (approximately 1000 g)
had a viscosity measured as described supra of 949 mPas and a pH of
from 8.5 to 9.0, determined on a 10% strength dispersion in
water.
Example 5 Preparation of Pigment Pastes
[0045] Coloured pigment pastes were prepared from the paste resin
according to the invention of Example 3 as follows (masses of the
constituents in g):
TABLE-US-00001 TABLE 1 Pigment Pastes according to the invention
Pigment Paste 5.1 5.2 5.3 5.4 resin of Example 3 40.30 40.30 40.30
35.40 deionised water 22.50 22.50 22.50 22.40 additive (1) 0.20
0.20 0.20 1.20 additive (2) 2.00 2.00 2.00 2.00 pigment 35.00 35.00
35.00 40.00 pigment colour Yellow (3) Red (4) Violet (5) Green (6)
(1) preservative additive based on isothiazolinone (.RTM. Additol
VXW 6372, Cytec Surface Specialties Austria GmbH) (2) defoamer
additive based on liquid hydrocarbons (.RTM. Additol VXW 6211,
Cytec Surface Specialties Austria GmbH) (3) .RTM. Hostaperm yellow
H3G (Pigment Yellow 154) (4) .RTM. Hostaperm red E3B (Pigment
Violet 19) (5) .RTM. Hostaperm violet RL spec (Pigment Violet 23)
(6) .RTM. Hostaperm Green GG01
Example 6 Application Results of Tinted Paints
[0046] Commercial water-borne pigment pastes (.RTM.Colanyl,
Clariant International Ltd.) and solvent borne pigment pastes
(.RTM.Hostatint, idem) in different colours using the pigments
.RTM.Hostaperm yellow H3G (Pigment Yellow 154), .RTM.Hostaperm red
E3B (Pigment Violet 19), .RTM.Hostaperm violet RL spec (Pigment
Violet 23), and .RTM.Hostaperm Green GG01, were compared to the
pigment pastes of Example 5 made from the same pigments as the
commercial grades, but with the paste resin of Example 3, by
preparing tinted paints from the solvent-borne white alkyd paint of
Example 4.1 and the water-borne white alkyd paint of Example
4.2.
[0047] The pigment pastes 5.1 through 5.4, and for comparison, the
commercial water-borne and solvent-borne pigment pastes were used
as tinting pastes to prepare coloured paints based on the white
paints of Examples 4.1 and 4.2, according to the following
recipes:
TABLE-US-00002 TABLE 2 Paint Preparation (Pigment Paste Data and
Mass of Pigment Paste in g) Pigment Paste Data Mass of Pigment
Paste in g for Viscosity* Mass Fraction sb White wb White Paint in
of Pigment Paint (-1) of Paint (-2) of No. mPa s in % Example 4.1
Example 4.2 6.1- 868 35 5.0 5.0 6.2C- 706 33 5.3 5.3 6.3H- 1700 33
5.0 5.0 6.4- 439 35 5.0 5.0 6.5C- 580 32 5.4 5.4 6.6- 300 35 5.0
5.0 6.7C- 502 30 5.8 5.8 6.8H- 1000 20 8.8 8.8 6.9- 326 40 5.0 5.0
6.10C- 340 50 4.0 4.0 6.11H- 970 45 4.4 4.4
[0048] Paints 6.1, 6.4. 6.6 and 6.9 were prepared with the tinting
pastes 5.1, 5.2, 5.3 and 5.4, respectively. Paints 6.2C, 6.5 C, 6.7
C and 6.10 C were prepared with the water-borne pigment pastes
.RTM.Colanyl yellow H3G100, .RTM.Colanyl red 3B130, .RTM.Colanyl
violet RL131, and .RTM.Colanyl green GG131, respectively, and
paints 6.3H, 6.8H, and 6.11H were prepared with the solvent-borne
pigment pastes .RTM.Hostatint yellow AH3G100, .RTM.Hostatint violet
ARL 100, and .RTM.Hostatint green GG30, respectively. A "1" or a
"2" are suffixed to the paint designations depending on whether the
paint had been prepared using 152 g of the solvent-borne (sb) white
paint 4.1 or 162 g of the water-borne (wb) white paint 4.2.
[0049] Gloss and colour strength were measured on paint films
prepared from these paints with an applicator frame (BYK-Gardner
PA-2056) in a wet film strength of 150 .mu.m on a glass panel (10
cm.times.15 cm) and dried for twenty-four hours at room temperature
(21.degree. C.). The results are summarised in table 3. Gloss was
measured at room temperature (21.degree. C.) and 50% relative
humidity, with a BYK micro-trigloss meter, and colour strength was
rated with "1" denoting highest tinting power, and "5" denoting low
tinting power.
TABLE-US-00003 TABLE 3 Results from Paint Tests Paint 6.XX-1 (sb)
Paint 6.XX-2 (wb) Paint Gloss Gloss Colour Gloss Gloss Colour No.
20.degree. 60.degree. strength 20.degree. 60.degree. strength 6.1-
83.8 92.0 1 76.5 86.5 1 6.2C- 80.8 90.6 5 75.6 86.5 1 6.3H- 82.3
91.8 1 53.0 77.7 5 6.4- 83.2 90.5 1 75.1 85.1 1 6.5C- 80.9 88.2 4-5
73.5 84.5 3 6.6- 82.6 89.8 1 71.3 84.3 2 6.7C- 80.1 86.9 4 73.4
84.2 1 6.8H- 82.5 89.1 3-4 62.4 80.7 5 6.9- 83.1 90.7 2 75.9 85.2 3
6.10C- 81.0 87.7 5 76.0 85.8 3 6.11H- 82.1 90.4 2 66.1 81.5 5 white
-- 76.5 86.7 -- paint
[0050] It can be seen from this table that pigment pastes made with
the paste resin according to the invention yield favourable results
in combination with a water-borne white paint, comparable to those
obtained with a commercial water-borne pigment paste, whereas a
commercial solvent-borne pigment paste in combination with the same
water-borne paint has less gloss and colour strength.
[0051] On the other hand, pigment pastes made with the paste resin
according to the invention also yield favourable results in
combination with a solvent-borne white paint, comparable to those
obtained with a commercial solvent-borne pigment paste, whereas a
commercial water-borne pigment paste in combination with the same
solvent-borne paint has less gloss and colour strength.
[0052] The paste resin according to the invention therefore has
exceptionally good compatibility with both solvent-borne and
water-borne paints, in both cases performing on par with the same
class of commercially available state-of-the-art pigment pastes,
with no trade-off for universal compatibility. The same results
have been found when pigmented paints were made based on
solvent-borne and water-borne acrylic paint binders. It is
therefore sufficient for paint formulation to prepare only one
tinting paste based on the paste resin according to the invention,
for use with water-borne or solvent-borne alkyd paints and also for
use with water-borne or solvent-borne acrylic paints, thereby
eliminating the need to stock different pigment pastes for each of
the named paint binders.
[0053] It has also been found that pigment pastes prepared with
paste resins according to the invention may be used for hybrid
resins based on acrylated alkyd resins, as well as for urethane
alkyd and urethane acrylic resins as paint binders, and also in
combination with the inorganic and organic pigment materials
mentioned earlier.
[0054] The important effect of monomers of class A3 in the basic
acrylic copolymer resin can best be seen from a comparison where
this class of monomers A3 is missing.
Example 7 Pigment Paste from a Comparative Acrylic Copolymer
Resin
[0055] 7.1 Comparative Acrylic Resin
[0056] A mixture of 250 g of dimethylaminoethyl methacrylate, 650 g
of n-butylacrylate, and 100 g of hydroxyethyl acrylate were added,
concurrently with a solution of 20 g of azobis-isovaleronitrile in
70 g of methoxypropanol, over a period of eight hours to a glass
vessel charged with 160 g of methoxypropanol kept at 85.degree. C.,
and the contents of the vessel were stirred under a nitrogen
blanket. After completion of the addition, the reaction mixture was
stirred for two more hours, a further quantity of 1 g of the same
radical initiator was added, dissolved in 10 g of methoxypropanol,
and the reaction mixture was stirred for two more hours. Further 20
g of methoxypropanol were then added, and the mixture was allowed
to cool to room temperature.
[0057] 7.2 Mixture of Alkyd and Acrylic Resins
[0058] 129 g of the acrylic resins solution of Example 7.1 were
transferred to a glass vessel, the solvent methoxypropanol was
removed by distillation at 140.degree. C. under reduced pressure.
The vessel was then flushed with nitrogen, and after cooling to
below 100.degree. C., 133 g of the alkyd resin of Example 1 were
added, and well mixed with the acrylic resin at 80.degree. C. for
one hour. The mixture was cooled under stirring by switching off
the heating, and by adding 313 g of fully deionised water over a
period of thirty minutes. The vessel and its contents were then
allowed to cool to ambient temperature. An inhomogeneous resin and
water mixture having a mass fraction of solids of about 45% was
obtained.
[0059] 7.3 Preparation of a Pigment Paste
[0060] A sample of 30.1 g of the mixture of Example 7.2 was taken
immediately after homo-genisation and before phase separation,
mixed with 27.7 g of deionised water, 0.2 g of an
isothiazolinone-based preservative (.RTM.Additol VXW 6372, Cytec
Surface Specialties Austria GmbH), 2 g of a defoamer based on
liquid hydrocarbons (.RTM.Additol VXW 6211, Cytec Surface
Specialties Austria GmbH), and 40 g of a red quinacridone pigment
(Pigment Violet 19, .RTM.Hostaperm Red E3B, Clariant Deutschland
GmbH). The mixture was homogenised on a bead mill at room
temperature (21.degree. C.) for thirty minutes.
[0061] 7.4 Preparation of a Tinted Paint
[0062] A tinted paint was made by adding 5 g of the pigment paste
of Example 7.3 to 152 g of the solvent-borne white alkyd paint of
Example 4.1. Gloss and colour strength were measured on paint films
prepared from these paints with an applicator frame (BYK-Gardner
PA-2056) in a wet film strength of 150 .mu.m on a glass panel (10
cm.times.15 cm) and dried for twenty-four hours at room temperature
(21.degree. C.). The results are summarised in table 4. Gloss was
measured at room temperature (21.degree. C.) and 50% relative
humidity, with a BYK micro-trigloss meter, and colour strength was
rated with "1" denoting highest tinting power, and "5" denoting low
tinting power.
TABLE-US-00004 TABLE 4 Results using a Paste Resin made from a
Comparative Acrylic Resin Paint Gloss at 20.degree. Gloss at
60.degree. Colour Strength 7.4 51 79 5
[0063] Similar results were obtained when a water-borne alkyd paint
(the white paint of Example 4.2) was used in combination with the
pigment paste of Example 7.3.
[0064] This comparison shows that gloss and colour strength are
markedly improved in tinted paints if a hydrophilically modified
basic acrylic resin is used as one component of a paste resin,
together with the alkyd resins according to the invention. This
beneficial effect is seen both in solvent-borne and in water-borne
paints.
* * * * *