Note: Descriptions are shown in the official language in which they were submitted.
s 2166290
Modular sY8tem and Process for the Production of aqueous
coatinq comPositions.
This invention relates to a modular system (a mixed system
composed of modules), which is suitable for the production
of various types of aqueous coating compositions. In
particular, it is suitable both for the production of
aqueous effect base lacquers, single-tone aqueous base
lacquers and aqueous single-coat topcoat lacquers with an
adjustable colour tone and/or effect, and for the
production of aqueous clear lacquers, which may in
particular be used in automotive and automotive component
lacquer coating.
Water-borne lacquer systems are being used to an ever
increasing extent in automotive and automotive component
lacquer coating. Especially with regard to aqueous base
lacquers, there is, for example, a requirement for a
constantly changing number of colour tones and effects,
which is rendering economic production and storage
increasingly difficult. One way to solve this problem is to
provide a limited number of individual, storable components
which, depending upon the desired effect or colour tone,
may be combined shortly before application to produce the
finished, aqueous base lacquer.
EP-A-0 399 427 thus describes a modular aqueous base
lacquer system consisting of five components which, once
combined, yield a complete aqueous base lacquer. In this
process, the effect component, the component with the
effect pigments, must be produced and stored without water.
This is achieved by solubilising, for example, metal
pigments in a solvent-based solution of an alkyd, acrylate
or polyester resin and in an organic solvent. The aqueous
base lacquers formulated with this effect component thus
have an undesirably high solvent content. Moreover, a
separate neutralisation component is necessary which
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contains ammonia to neutralise the acidic resins in the
effect, resin and pigment component.
EP-A-O 468 293 and EP-A-O 471 972 also describe aqueous
lacquers based on various components. It is, however,
necessary for the effect component to be anhydrous. The
resins contained in the effect component and pigment
component are anionically or optionally non-ionically
modified. In these cases too, a neutralising component
containing ammonia is provided.
DE-A-4 110 520 describes a mixed system which is intended
to be suitable for the production of aqueous pigmented
coating compositions with precisely adjusted colour
shading. In particular, aqueous base lacquers are to be
produced using this method. The mixed system consists of
various pigmented base coatings (A), which contain less
than 5 wt.~ of water, are preferably anhydrous and contain
pigments, solvents and water-dilutable binders, and a
pigment-free component (B) containing water, which in
particular contains water-dilutable binders and/or
rheological additives. The water-dilutable binders
contained in component A) are present in organic solvents.
The aqueous base lacquers formulated in this manner thus
have an undesirably high solvent content. The complete
coating compositions are produced by mixing the components
directly before application, they are not stable in
storage.
The as yet unpublished German applications P 4 301 498 and
P 4 301 991 from this applicant describe modular systems
(mixed systems) for the production of aqueous single-tone
and effect base lacquers, which each consist of a binder
module and a colour and/or effect module. Both the binder
module and the colour and effect module contain anionically
and/or non-ionically stabilised water-dilutable resins.
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The object of the present invention is to provide a modular
system (mixed system) which, starting from a standard
binder module, may be used for the production of various
aqueous coating compositions, sucn as base lacquers,
single-coat topcoat lacquers and/or clear lacquers, by
means of an appropriate combination of the individual
modular components. In this system, both the individual
modular components and the coating compositions which may
be produced therefrom are intended to be stable in storage
for an extended period and to have a low solvent content.
The individual modular components of the system are
intended to be simply miscible with each other in order to
produce the particular desired coating composition.
It has been found that this object may be achieved by the
provision of an aqueous modular system on the basis of
cationically stabilised resins. The modular system consists
of at least two modular components, wherein one of the
modular components is in each case a binder module and the
second modular component is selected from among a colour
module, an effect module, a crosslinking module and/or a
rheological module depending upon the use of the coating
composition produced with the modular system or as a
function of the desired achievable effect.
The present invention accordingly provides a modular system
for the production of aqueous coating compositions,
contalnlng
A) at least one aqueous binder module containing one or
more cationically stabilised water-dilutable
(meth)acrylic copolymers and one or more cationically
stabilised water-dilutable polyurethane resins and/or
one or more cationically stabilised water-dilutable
(meth)acrylated polyurethane resins, optionally
combined with non-ionically stabilised water-dilutable
binders, water, optionally together with one or more
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organic solvents and/or conventional lacquer
additives,
together with at least one of the following modules:
B) one or more colour modules containing water, one or
more coloured pigments and/or extenders and one or
more cationically stabilised polyurethane paste
resins, at least 6 wt.% of water, optionally together
with one or more water-dilutable cationically and
optionally non-ionically stabilised binders, one or
more organic solvents and/or conventional lacquer
additives,
and/or
C) one or more effect modules containing water, one or
more effect pigments, at least 6 wt.% of water, one or
more cationically stabilised water-dilutable
(meth)acrylated polyurethane resins, which may
optionally be present combined with further
cationically or non-ionically stabilised water-
dilutable binders, optionally together with one or
more organic solvents and/or conventional lacquer
additives
and/or
D) one or more crosslinking modules containing one or
more crosslinking agents, optionally together with one
or more organic solvents, water and/or conventional
lacquer additives,
and/or
E) one of more rheological modules containing one or more
organic and/or inorganic rheological control agents,
optionally together with one or more cationically, or
cationically and non-ionically and/or non-ionically
stabilised water-dilutable binders and/or one or more
organic solvents and/or water.
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Modules are here taken to be storage-stable components from
which a complete coating composition may be produced by
mixing, which composition may optionally still be adjusted
to application viscosity.
It has been found that it is possible, by mixing the
individual modules prepared according to the invention, to
prepare various aqueous coating compositions, such as for
example aqueous effect base lacquers, single-tone base
lacquers, single-coat topcoat lacquers and clear lacquers,
without needing to make use of different starting
materials. This results in the advantage that coating
compositions for different intended applications may be
produced starting from standard components. This may be
achieved by appropriate selection of the modular components
defined within the modular system according to the
invention; it is also possible to obtain desired adjustable
colour tones and/or effects by mixing the individual
modules.
It has been found that stable modules and complete systems
may be obtained according to the invention if the colour
and effect modules contain at least 6 wt.~, preferably at
least 10 wt.%, of water.
Single-coat topcoat lacquers which may be produced from the
modular system according to the invention should here be
taken to be those coating compositions which form the final
layer in multicoat lacquer coatings instead of the
conventional two-coat base lacquer/clear lacquer structure.
Various embodiments of each of modules A) to E) may be
prepared.
In addition to the stated modular system, the invention
also relates to a process for the production of aqueous
coating compositions by mixing at least one aqueous binder
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component with further coating composition components,
which process is characterised in that a supply of at least
one storage-stable binder module A), together with at least
one storage-stable colour module B), effect module C),
S crosslinking module D) and/or rheological module E), is
prepared and optionally stored, the modules being
separately prepared, wherein the individual modules are
mixed together as required in a quantities such that the
solids content arising therefrom, relative to the total
solids content of the coating compositions, assumes the
following percentages:
binder modules A): 5 - 99 wt.%
colour modules B): 0 - 60 wt.
effect modules C): 0 - S0 wt.%
crosslinking modules D): 0 - 50 wt.% and
rheological modules E): 0 - 50 wt.%
wherein the sum of the percentages should amount to 100%.
In particular, aqueous coating compositions with a solids
content of 10 to 80 wt.% at application viscosity are
produced. The invention also relates to the aqueous coating
compositions produced in accordance with the process
according to the invention.
According to a preferred embodiment, the binder module A)
used according to the invention contains 10-99 wt.% of the
cationically stabilised (meth)acrylic copolymer, 2-70 wt.%
of the cationically stabilised polyurethane resin and
0.2-60 wt.% of the cationically stabilised (meth)acrylated
polyurethane resin, wherein the stated percentages relate
to the total binder solids content in the binder module and
should add up to 100%.
Cationically stabilised water-dilutable binders, optionally
combined with non-ionically stabilised water-dilutable
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binders are prepared in at least a proportion of the
modules prepared according to the invention. "Cationically
stabilised" should here and below also be taken to mean the
term "cationically and additionally optionally
non-ionically stabilised". The term "water-dilutable" used
here should also be taken to mean '~water-soluble". The
binders may in general be, for example, (meth)acrylic
copolymers, polyurethane resins or (meth)acrylated
polyurethane resins which have basic groups which form
cationic groups by at least partial neutralisation. The
binders may be self or extrinsically crosslinking. These
binders and the specific examples of these binders stated
below are, as mentioned, generally usable in the modules
according to the invention; they are particularly
conveniently suitable for binder module A).
Cationic (meth)acrylic copolymers, polyurethane resins
and/or (meth)acrylated polyurethane resins may, for
example, be those with a number average molecular weight
(Mn) of 500 to 500000, an OH value of 0 to 450, an amine
value of 20 to 200 and a glass transition temperature of
-50C to +150C.
Examples of such cationic resins are described in
DE-A-41 34 301, DE-A-40 11 633, DE-A-41 34 290 and
DE-A-42 03 510.
The (meth)acrylic copolymer resins containing basic groups
preferably have an OH value of 30-200, a number average
molecular weight (Mn) of 1000 to 200000 and an amine value
of 15-150, particularly preferably an amine value of
25-100. On neutralisation, they are preferably present in
aqueous systems at a pH value of 5 to 7. Particularly
preferred (meth)acrylic copolymer resins have a number
average molecular weight (Mn) of 4000 to 50000, a hydroxyl
value of 60 to 175, an amine value of 20 to 100 and a glass
transition temperature of -20 to ~75C. They may be
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produced, for example, by solution polymerisation or
emulsion polymerisation or copolymerisation using prior art
methods, as for example described in DE-A-15 46 854,
DE-A-23 25 177 or DE-A-23 57 152. They are produced, for
example, from (meth)acrylate monomers, optionally together
with further free-radically polymerisable monomers. The
free-radically polymerisable monomers, i.e. the
(meth)acrylate monomers and/or further free-radically
polymerisable monomers are at least in part monomers
containing amino groups or free-radically polymerisable
monomers which may contain both amino groups and hydroxyl
groups. They may be used mixed with other free-radically
polymerisable monomers.
The method here is preferably to use 6 to 40 parts by
weight of free-radically polymerisable monomers containing
amino groups and 4 to 50 parts by weight of free-radically
polymerisable monomers containing hydroxyl groups, or 8 to
60 parts by weight of free-radically polymerisable monomers
containing hydroxy and amino groups per 10 to 90 parts by
weight of free-radically polymerisable monomers, which
contain no further reactive groups. Of the free-radically
polymerisable monomers used, preferably more than 50 wt.%
and particularly preferably more than 70 wt.~ are
(meth)acrylate monomers. These (meth)acrylate monomers may,
by virtue of their ester functions, contain amino groups
and/or hydroxyl groups or may occur as further non-
functional monomers.
Suitable free-radically polymerisable monomers are
virtually any ethylenically unsaturated monomers, as are
common for free-radical polymerisation and which comply,
for example, with Alfrey & Price's Q and e scheme for
copolymerisation (c.f. Brandrup & Immergut, Polymer
Handbuch, 2nd edition, John Wiley & Sons, New York 1975).
The basic poly(meth)acrylate resins may also contain onium
groups, such as quaternary ammonium groups, sulphonium or
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g
phosphonium groups, apart from or in addition to the amino
groups.
Examples of free-radically polymerisable monomers
containing hydroxyl groups are (meth)acrylic acid
hydroxyalkyl esters, such as for example 2-hydroxyethyl
acrylate, 2-hydroxypropyl methacrylate, 1,4-butanediol
monoacrylate, 2,3-dihydroxypropyl methacrylate,
pentaerythritol monomethacrylate, polypropylene glycol
monoacrylate, adducts of (meth)acrylic acid and glycidyl
esters, for example of versatic acid or also fumaric acid
dihydroxyalkyl esters.
N-hydroxyalkyl(meth)acrylamide or N-hydroxyalkylfumaric
acid mono- or diamides such as, for example,
N-hydroxymethyl-acrylamide or
N-(2-hydroxypropyl)methacrylamide may, however, also be
used. Particularly elastic properties may be achieved by
using a reaction product of hydroxyalkyl (meth)acrylates
with ~-caprolactone. Other compounds containing hydroxyl
groups are allyl alcohol, monovinyl ethers of polyalcohols,
in particular of diols, such as for example the monovinyl
ethers of ethylene glycol or butanediol, together with
allyl ethers or esters containing hydroxyl groups, such as
- 2,3-dihydroxypropyl monoallyl ether, trimethylolpropane
monoallyl ether or 2,3-dihydroxypropanoic acid allyl ether.
Hydroxyethyl, hydroxypropyl and/or 1,4-butanediol
mono(meth)acrylate are particularly suitable.
Monomers containing amino groups which may be used are, for
example, monomers of the general formula
R - CH = CH' - X - A - N(R' ' ) 2
wherein
R means -R ' or -X-CnH2n+1,
R' means -H or ~CnH2n+1 and
R means -R , -CnH2nOH and/or -CnH2nNR2, wherein R is
3 5 defined as above, and
X means -COO-, - CONH-, - CH20 - or -o-,
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A means ~CnH2n- or -CnH2n-CHOH-CH2 and
n means 1 to 8, preferably 1 to 3.
Examples of unsaturated monomers containing N groups are
N-dialkyl- or N-monoalkylaminoalkyl (meth)acrylate or the
corresponding N-alkanol compounds, such as for example
N-diethylaminoethyl acrylate or N-tert.-butylaminoethyl
acrylate, N-dialkyl- or N-monoalkylaminoalkyl(meth)-
acrylamide or the corresponding N-alkanol compounds, such
as for example N-dimethylaminoethanolacrylamide and/or
heterocyclic compounds containing vinyl groups with one or
more basic nitrogen atoms, such as for example
N-vinylimidazole.
Component A) aminopoly(meth)acrylate resins may also, as
described in DE 40 11 633, be produced by a polymer-
analogous reaction. A copolymer containing acrylamide
groups may thus, for example, be reacted with formaldehyde
and a secondary amine and/or aminoalcohol. A particularly
preferred process is described in DE-A-34 36 346. In this
process, monoethylenically unsaturated monomers containing
epoxide groups are initially copolymerised to yield the
copolymer. The product is then reacted with excess ammonia,
primary and/or secondary monoamines and/or
monoaminoalcohols and the amine excess then removed by
distillation.
A further suitable group of binders comprises, for example,
cationically or cationically/non-ionically stabilised
polyurethanes. These may be synthesised from any
conventional structural units known to the person skilled
in the art. For example, during production of polyurethane
resins, the equivalent ratio of the diisocyanate used is
adjusted relative to the polyols and diols used in such a
manner that the complete polyurethane resin preferably has
a number average molecular weight (Mn) o~ 3000 to 200000,
particularly preferably of 10000 to 40000 and an amine
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value of 15 to 120, particularly preferably of 20 to 100.
The pH value is preferably adjusted to 5 to 7 on
neutralisation.
Urethanised polyesters, which may also be hydroxy-
functional, constitute a preferred group of basic
polyurethane resins, wherein, for example, basic groups in
the form of amino groups are either directly condensed into
the polyesters as aminoalcohols or, under milder
conditions, are incorporated into the polymer chain by
polyaddition or attached to the polymer chain. Thus, for
example, a preferably linear polyester containing OH groups
is syntnesised by reacting the polyester with dialkyl-
aminodialcohols and diisocyanates. If the reaction is
performed with a substoichiometric quantity of isocyanate,
the resin, once neutralised with acids, must be directly
dispersible in water. If, on the other hand, an isocyanate
excess is used, the resultant NCO prepolymer may be
dispersed in water and converted into a polyurethane(urea)
dispersion by chain extension with a polyamine. Such
polyurethane(urea) dispersions may also be used according
to the invention as polyurethane resins.
Polyurethane(urea) dispersions containing basic groups are
produced in a known manner, for example by chain extension
of a cationic prepolymer having a terminal isocyanate group
with polyols, polyamines and/or hydrazine compounds,
wherein chain extension is performed before or after
neutralisation of the tert.-amino groups with these in
water. The amine value is controlled by the quantity of
compounds containing cationic groups in the prepolymer
containing isocyanate groups used during production.
Particle size is dependent upon the molecular weight of the
polyol used, for example OH polyester (polyester polyol),
the amine value and the sequence of synthesis. Number
average molecular weight is preferably between 3000 and
500000, particularly preferably above 5000 and below 50000.
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Polyurethane dispersions containing urea groups are
preferably produced which contain at least 2, preferably 4
urethane groups and at least one tert.-amino group,
especially a dialkylamine group in the NCO prepolymer.
A detailed description of the production of the
polyurethane and polyurethane(urea) dispersions discussed
above is given, for example, in DE-A-41 34 301 and DE-A-
40 11 633.
Further binders which may readily be used in the binder
module are those in which a cationic polyurethane resin and
a (meth)acrylic copolymer are combined together in the form
of interpenetrating resin molecules.
(Meth)acrylated polyurethane dispersions constitute a
further group for the binder module A) which are also
suitable for formulating effect modules. These are, for
example, so-called polymer dispersions which are obtained
by emulsion polymerisation of (meth)acrylic monomers in
polyurethane dispersions, which are cationically and/or
non-ionically stabilised. The (meth)acrylic monomers used
may also contain cationic groups, groups convertible into
cationic groups (such as amino groups) and/or non-ionic
hydrophilic groups; such monomers may be used not only to
stabilise already stabilised polyurethane dispersions, but
also to stabilise polyurethanes which themselves do not yet
contain any stabilising groups. Particularly preferred
polyurethane dispersions are those which are copolymerised
by emulsion polymerisation of so-called polyurethane
macromers, i.e. polyurethanes with covalently attached
terminal and/or lateral vinyl groups, with unsaturated
monomers, preferably (meth)acrylic acid derivatives. The
amine value of such dispersions is from 5-150, preferably
from 10-100; the hydroxyl value from 0-150, preferably from
15-120.
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According to a preferred embodiment, mixtures are used as
the binder for the binder module A) which contain
(meth)acrylic copolymers, as described above, and
polyurethane resin. Suitable (meth)acrylate copolymers are
in particular those described above with an OH value of 30
to 200, a number average molecular weight (Mn) of 100 to
200000 and an amine value of 15 to 150. Suitable
polyurethane resins are in particular those described abov~
with a number average molecular weight (Mn) of 3000 to
200000 and an amine value of 15 to 120. These mixtures are
also preferably present in the binder module at a pH value
Of 5 to 7.
In the cationically stabilised binders used according to
the invention, solubility may be influenced by the number
of amino groups. The amine value should preferably be 20 to
200 mg KOH/g of solid resin, preferably between 30 and 150.
Primary, secondary and/or tertiary amino groups may be
present. Tertiary amino groups are preferred.
The hydroxyl value influences crosslinking density. It
should preferably be between 20 and 400. Each binder
molecule should here preferably contain an average of at
least two reactive groups, for example OH or NH groups.
Reactivity is influenced by the nature of the groups, thus
primary amino or hydroxyl groups are more reactive than
secondary groups, wherein NH groups are more reactive than
OH groups. It is preferred for the binder to contain
reactive amino groups. The binders according to the
invention may bear further attached crosslinkable groups,
for example blocked isocyanate groups, alkoxysilane groups
or transesterifiable groups. In this case, these are self
crosslinking binders. It is, however, possible additionally
to mix crosslinking agents into the binders. The molecular
weight (M~) of the crosslinking agents is, for example, S00
to 20000, in particular 1000 to 10000. The crosslinking
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agents may be present either directly in the binder module
A) or in a separate crosslinking module (D).
The cationic binders may be physically drying, self or
extrinsically crosslinking; this applies in particular to
the cationic binders contained in binder module A). The
cationic binders may contain attached crosslinkable groups,
for example blocked isocyanate groups or transesterifiable
groups. In this case, these are self crosslinking binders.
It is, however, possible to add additional crosslinking
agents in a separate crosslinking module.
The modules, in particular binder module A) may optionally
also contain non-ionically stabilised binders.
Examples of suitable non-ionically stabilised binders are
those binders in which water-dilutability is achieved by
incorporating polyether segments into the resin molecule.
Examples of such stabilised resins are polyurethane or
polyurethane acrylate resins, as are described in EP-A-
0 354 261, EP-A-0 422 357 and EP-A-0 424 705.
The binder module A) necessarily contained in the modular
system according to the invention may contain an aqueous
binder, but a combination of aqueous binders may also be
present. The binders may here each be separately produced
and then stored as individual modules or a mixture of the
binders is produced and then stored as one or more
multicomponent binder modules.
Binder module A) may contain rheological control agents and
small proportions of conventional solvents, preferably less
than 5 wt.~. The solids content of the binder module is
preferably 10-50 wt.~, particularly preferably 15-40 wt.~.
Binder module A) contains neutralising agents for the basic
resins. These are acids, preferably organic monocarboxylic
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acids, such as for example formic acid, acetic acid,
propionic acid. Hydroxycarboxylic acids are in particular
well suited, such as for example lactic acid, glycolic
acid, diglycolic acid, malic acid, citric acid, mandelic
acid, tartaric acid, hydroxypropionic acid, dimethylol-
propionic acid. The neutralising agents are added in the
desired quantity to achieve water-compatibility or
water-solubility. Neutralisation may be complete or
partial. The pH value in binder module A) is preferably 5
to 7.
Colour module B) is an aqueous preparation which contains
one or more coloured pigments and/or extenders, one or more
cationically stabilised polyurethane paste resins, water
optionally together with water-dilutable cationic binders
optionally combined with non-ionically stabilised binders,
one or more organic solvents and/or conventional lacquer
additives. Water is present in a quantity of at least
6 wt.%, preferably of at least 10 wt.~.
Each colour module B) preferably contains no more than four
different coloured pigments and/or extenders, the aqueous
colour modules particularly preferably contain only one
coloured pigment or only one extender. The colour modules
of the systems according to the invention may contain
conventional inorganic and/or organic coloured pigments
and/or extenders as well as transparent pigments. Examples
of inorganic or organic coloured pigments or extenders are
titanium dioxide, micronised titanium dioxide, iron oxide
pigments, carbon black, silicon dioxide, barium sulphate,
micronised mica, talcum, azo pigments, phthalocyanine
pigments, quinacridone or pyrrolopyrrole pigments.
Cationically stabilised polyurethane paste resins which may
be used in the colour module preferably have a solids
content (relative to the total weight of the colour module)
of 20-S0 wt.~, a viscosity of 0.5-50 mPa-s at 25C and are
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preferably 70 to 100% neutralised with monocarboxylic
acids. Examples of suitable monocarboxylic acids are those
already stated above in the description of the binder
module.
Polyurethane paste resins preferably used in the colour
module B) are, for example, basic polyesterurethane resins
during the production of which the equivalent ratio of the
diisocyanate used is adjusted relative to the polyols and
diols used in such a manner that the complete polyurethane
resin, for example polyesterurethane resin, has a number
average molecular weight (Mn) of 3000 to 200000, preferably
of below 50000. The OH value is preferably 0 to 80,
particularly preferably 10 to 65; the amine value is
preferably 15 to 150, particularly preferably 10 to 100.
The ratio of the OH groups of the polyol, for example
polyester polyol and diol, to the ~CO groups of the
isocyanates is preferably maintained above 1.0 to 1.2:1;
the viscosity of the polyurethane resin, for example
polyesterurethane resin, is preferably 1 to 30 Pa-s,
particularly preferably above 2 and below 15 Pa-s, measured
as a 60% solution in butoxyethanol at 25C.
The colour module B) which may be used according to the
invention may, in addition to the basic polyurethane paste
resin, contain cationically stabilised water-dilutable
binders, optionally combined with non-ionically stabilised
binders. These may, for example, be the same resins as have
already been described in binder module A). Other
cationically stabilised binders may, however, also be
included, for example polyester resins.
The colour module B) may furthermore contain small
proportions of at least one water-miscible solvent, such as
alcohols, for example monoalcohols, such as butanol,
n-propanol, isopropanol; ether alcohols, for example
butoxyethanol, butoxypropanol, methoxypropanol, dialcohols,
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such as glycols, for example ethylene glycol, polyethylene
glycol; trialcohols such as glycerol; ketones, for example
acetone, methyl ethyl ketone; N-methylpyrrolidone; ethers,
for example dipropylene glycol dimethyl ether.
The module may, as already described in A), also contain
acids as neutralising agents. Examples are organic
monocarboxylic acids, such as for example formic acid,
acetic acid, dimethylolpropionic acid.
It may be favourable for the colour module B) to contain
one or more rheological control agents. These may, for
example, be substances or mixtures as are described in the
production of the rheological module E). These may be added
directly during production of the colour module or
subsequently mixed in as a complete rheological module.
The colour module B) containing water may furthermore
contain conventional lacquer additives, such as for example
wetting agents, defoaming agents, levelling agents,
dispersion auxiliaries.
The colour module B) containing water is generally produced
in such a manner that the coloured pigment and/or extender
is ground in the paste resin. The paste resin may be
present in un-neutralised, partially neutralised or
completely neutralised form in an organic, at least
partially water-miscible solvent or in an aqueous solution
or dispersion. Solutions or dispersions containing water
are preferred. This may proceed in conventional apparatus
familiar to the person skilled in the art. The module is
then optionally formulated with a further proportion of
paste resin and/or the cationically and optionally
non-ionically stabilised water-dilutable binders optionally
contained in the colour module (B) and/or further
additives.
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Storage-stable, aqueous colour modules (B) are obtained
with a pigment or extender:binder ratio of, for example,
0.01:1 to 10:1, relative to solids weight. Solids content
is preferably 20-80 wt.%.
The water content in the colour module is preferably at
least 6 wt.~, particularly preferably at least 10 wt.~.
The effect module C) is an aqueous preparation which
contains at least one or more effect pigments and water,
optionally together with one or more organic solvents, one
or more cationically stabilised water-dilutable
(meth)acrylated polyurethane resins, which may be present
combined with non-ionically stabilised water-dilutable
binders, optionally together with one or more organic
solvents and conventional lacquer additives.
Effect pigments are those pigments which bring about a
decorative effect in lacquer coatings and additionally, but
not exclusively, may bring about a coloured effect. Effect
pigments are in particular distinguished by a lamellar
structure. Examples of effect pigments are: metal pigments,
for example made of aluminium, copper or other metals;
interference pigments, such as for example metal pigments
coated with metal oxides, for example aluminium coated with
titanium dioxide or mixed oxide, coated micas, such as for
example mica coated with titanium dioxide and graphite
effect pigments.
Many such effect pigments varying in particle size and
shape are commercially available. The pigments are selected
on the basis of the desired effect in the lacquer film.
Preferably, effect modules are produced with only one
pigment. It is, however, possible for effect modules to
contain two or more different effect pigments.
- 2166290
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The effect module may moreover contain small proportions of
at least one water-miscible solvent, as for example
described in A), such as alcohols, ~or example
monoalcohols, such as butanol, n-propanol; ether alcohols,
for example butoxyethanol, butoxypropanol, methoxypropanol;
dialcohols, such as glycols, for example ethylene glycol,
polyethylene glycol; trialcohols such as glycerol; ketones,
for example acetone, methyl ethyl ketone, N-methyl-
pyrrolidone; ethers, for example dipropylene glycol
dimethyl ether.
Examples of water-dilutable cationically stabilised
(meth)acrylated polyurethanes usable in the effect module
C) are those as were in particular described above for the
binder module A) as (meth)acrylated polyurethane
dispersions, in particular with an amine value-of 5 to 150,
preferably of 10 to 100 and a hydroxyl value of 0 to 150,
preferably of 15 to 120.
The effect module may contain rheological control agents.
These may, for example, be substances or mixtures as are
described below in the description of the rheological
module E).
These may be added directly during production of the colour
module or subsequently mixed in as a complete rheological
module.
The aqueous effect module may furthermore contain
conventional lacquer additives, such as for example wetting
agents, defoaming agents, neutralising agents, catalysts.
The effect module cont~;n;ng water is generally produced in
such a m~nn~r that the effect pigment, for example in the
form of a conventional commercial paste, is initially
introduced into a vessel, combined with water-dilutable
2 ~ 66290
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organic solvents and additives and optionally subsequently
mixed with the aqueous resin solution with shearing.
Storage-stable, aqueous effect modules are obtained with a
preferred pigment:binder weight ratio of 0.02:1 to 10:1.
The solids content of the entire effect module is
preferably 10-40 wt.~. The water content in the effect
module is at least 6 wt.~, particularly preferably at least
10 wt.~.
The modular system according to the invention may also
contain a crosslinking module D). The crosslinking module
D) is in particular used in the event that the coating
composition to be prepared is produced using those resins
which contain crosslinkable groups in their molecule.
Examples of crosslinking resins contained in the
crosslinking module are conventional crosslinking agents,
such as polyisocyanates, polyamines, blocked
polyisocyanates, amino resins, phenolic resins,
crosslinking agents containing siloxane groups and/or
transesterification crosslinking agents.
The polyisocyanates may be any desired organic
polyisocyanates with aliphatically, cycloaliphatically
and/or aromatically attached free isocyanate groups. They
are liquid at room temperature or liquefied by the addition
of organic solvents. At 23C, the polyisocyanates have a
viscosity of, for example, 1 to 6000 mPa-s, preferably of
above 5 and below 3000 mPa-s.
Such polyisocyanates are generally known and described, for
example, in DE-A-38 29 587 or DE-A-42 26 243.
The polyisocyanates are preferably polyisocyanates or
polyisocyanate mixtures with exclusively aliphatically
and/or cycloaliphatically attached isocyanate groups with
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an average NCO functionality of 1.5 to 5, preferably of 2
to 3.
Particularly suitable compounds are, for example, "lacquer
polyisocyanates" based on hexamethylene diisocyanate,
1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane
(IPDI) and/or bis(isocyanatocyclohexyl)methane and the per
se known derivatives of these diisocyanates with biuret,
allophanate, urethane and/or isocyanurate groups, from
which the excess starting diisocyanate has been removed
after production, preferably by distillation, down to a
residual content of less than 0.5 wt.~.
Sterically hindered polyisocyanates of the general formula
Rll Rll
OCN - C - A - C - NCO
R2 R2
are also very suitable, wherein
R1 is H or R2,
R2 is CnH2n+1 with
n being 1 to 6.
Substituents Rl and R2 are either linear or branched,
identical or different. The parent structure A may consist
of a single bond, an aromatic or alicyclic ring or an
aliphatic linear or branched C chain with 1 to 12 C atoms.
Examples of such substances are 1,1,6,6-tetramethyl-
hexamethylene diisocyanate, 1,5-dibutylpentamethyl
diisocyanate, p- or m-tetramethylxylylene diisocyanate of
the general formula
. . ` 21 66290
~,
- 22 -
CH~
CH3 ~ CH~ C ~ C - NCO
OCN - c ~ C - NCO c~ ~
in which R means H or Cl- C4 alkyl, and the corresponding
hydrogenated homologues, together with 2,3-bis-(8-
isocyanatooctyl)-4-octyl-5-hexylcyclohexane and
3(4)-isocyanatomethyl-1-methylcyclohexyl isocyanate. These
diisocyanates may also be reacted in a suitable manner to
yield more highly functional compounds, for example by
trimerisation or by reaction with water or trimethylol-
propane.
Examples of blocked isocyanates are any desired di- and/or
polyisocyanates in which the isocyanate groups are reacted
with a compound containing active hydrogen. Corresponding
prepolymers containing isocyanate groups may also be used
as the di- and/or polyisocyanates. These are, for example,
aliphatic, cycloaliphatic, aromatic, optionally also
sterically hindered polyisocyanates, as have already been
described above by way of example. Trifunctional, for
example tri- to pentafunctional aromatic and/or aliphatic
blocked isocyanates with a number average molecular weight
of 500-1500 are preferred.
Conventional blocking agents may be used. Thus, for
example, low molecular weight compounds containing acidic
hydrogen are known for blocking NCO groups. Examples of
such compounds are aliphatic or cycloaliphatic alcohols,
dialkylaminoalcohols, oximes, lactams, heterocyclics
containing NH groups, such as for example pyrazoles or
triazoles, imides, hydroxyalkyl esters, esters of malonic
acid or acetoacetic acid.
. ~` 2166290
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Amino resins are also suitable as crosslinking resins.
Amino resins are described, for example, in U17m~nn's
Encyclopedia of Industrial Chemistry, 5th edition, volume
A2, Amino resins entry, pages 115-141 (1985) and
Houben-Weyl, Methoden der Organischen Chemie, volume 14/2,
pages 319-399 (1962). The resins are produced in accordance
with the prior art and offered for sale by many companies
as commercial products.
Examples of such amino resins are amine/formaldehyde
condensation resins, which are produced by the reaction of
aldehydes with melamine, gl~n~m;ne, benzogu~n~m;ne or
dicyanodiamidé. The alcohol groups of the aldehyde
condensation products are then partially or completely
etherified with alcohols.
Further examples of crosslinking agents which may also be
contained in the crosslinking module are conventional
transesterification crosslinking agents.
Transesterification crosslinking agents are polyesters
containing no carboxyl groups with lateral or terminal
B-hydroxyalkyl ester groups. These are esters of aromatic
polycarboxylic acids, such as for example isophthalic acid,
terephthalic acid, trimellitic acid or mixtures thereof.
These are condensed, for example, with ethylene glycol,
neopentyl glycol, trimethylolpropane and/or
pentaerythritol. The carboxyl groups are then reacted with
optionally substituted 1,2-glycols to form B-hydroxyalkyl
compounds. The 1,2-glycols may be substituted with
saturated or unsaturated alkyl, ether, ester or amide
groups. The formation of hydroxyalkyl esters is also
possible in which the carboxyl groups are reacted with
substituted glycidyl groups, such as for example glycidyl
ethers and glycidyl esters.
The transesterification crosslinking agents preferably
contain more than 3 B-hydroxyalkyl ester groups per
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. . ~
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molecule and have a weight average molecular weight of 1000
to 10000, preferably of above 1500 and below 5000. The
polyesters containing no carboxyl groups with lateral and
terminal ~-hydroxyalkyl ester groups may be produced as is
described, for example, in EP-A-0 012 463.
Polyamine crosslinking agents suitable as crosslinking
resins are, for example, diamines and amines with more than
two amino groups, wherein the amino groups may be primary
and/or secondary. Suitable polyamines are also adducts
consisting of polyamines with at least two primary amino
groups and which may be modified by further functional
groups, for example with epoxy groups, with polyisocyanates
or with (meth)acryloyl compounds. Polymers into which the
amino-functional groups are only subsequently introduced by
reaction are also suitable as polyamines.
Examples of suitable polyamines are described in EP-A-
0 240 083 or EP-A-0 346 982. Examples of these are
aliphatic and/or cycloaliphatic amines with 2-24 atoms,
which contain 2-10 primary amino groups and 0-5 secondary
amino groups. Examples of these are hexamethylenediamine,
1,2-diaminocyclohexane, isophoronediamine, diethylene-
triamine or polyether polyamines.
Examples of conventional polyamines based upon modified
polyfunctional amine components with di- or polyfunctional
epoxy compounds are those produced using, for example,
diglycidyl or polyglycidyl ethers based on bisphenol A or
bisphenol F, polyglycidyl ethers of phenolformaldehyde or
novolaks; glycidyl ethers of fatty acids with 6-24 C atoms,
epoxidised polybutadienes or resins containing glycidyl
groups, such as polyesters or polyurethanes, which contain
one or more glycidyl groups per molecule.
Polyamidoamines may also be used, as are, for example,
described in EP-A-0 262 720. These are reaction products
2 1 66290
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prepared from mono- or polycarboxylic acids with polyamines
which contain primary amino groups.
Polyamine/isocyanate adducts may also be used. Suitable
isocyanates for this purpose are the aliphatic,
cycloaliphatic and/or aromatic di- or polyisocyanates
conventional in the lacquer sector.
Further methods for the synthesis of amino-functionalised
curing agents are described in EP-A-0 002 801 and in EP-A-
0 179 954. These are copolymers based on (meth)acrylic acid
derivatives which are reacted and functionalised with
diamines or alkyleneimines.
The crosslinking module D) may contain the crosslinking
agent alone. It may, however, also contain one or more
organic solvents, water and/or conventional lacquer
additives. These are, for example, the same solvents and
additives as are described for the other modules. The
module may in particular contain catalysts which accelerate
the reaction between the binder and crosslinking component.
When amine/formaldehyde resins are used, the catalysts used
are, for example, amine salts or readily hydrolysable
esters of organic sulphonic acids or sulphonamides, as may
be obtained as conventional commercial products. In the
event of a combination with polyisocyanates, organometallic
compounds, such as dibutyltin dilaurate may be used,
optionally combined with basic catalysts, such as
1,4-diazabicyclo[2.2.2]octane.
The modular system according to the invention may also
contain a rheological module E). This preferably contains
water and, as the rheological component, one or more
substances controlling the flow properties of the finished
aqueous effect base lacquer.
2 1 66290
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Examples thereof are polymer microparticles, as are for
example described in EP-A-0 038 127, inorganic
phyllosilicates, for example aluminium-magnesium silicate,
sodium-magnesium phyllosilicates and sodium-magnesium-
fluorolithium phyllosilicates of the montmorillonite type,associative thickeners, for example based on polyurethane
or cellulose, polyvinyl alcohol, poly(meth)acrylamide,
polyvinylpyrrolidone and polymeric urea compounds,
synthetic polymers with ionic groups, such as for example
poly~meth)acrylic acid. These substances are commercially
available in many forms.
Polyurethane-based cationic associative thickeners are
preferred here.
The polyurethane-based associative thickeners are resins
having the following schematic structure: hydrophilic
segments such as polyether structures (wherein these
preferably contain a proportion of ethylene oxide units,
preferably of 35~ or more, in the event that only polyether
structures are present) and/or cationic groups or groups
convertible into cations are incorporated into the main
polymer chain. In contrast, long-chain hydrophobic
components are incorporated onto the chain ends. They are
responsible for the thickening action of such systems. They
are synthesised in a similar manner to the polyurethane
synthesis methods already described. Any usual starting
materials for polyurethane synthesis available to the
person skilled in the art are suitable for this purpose.
Long-chain fatty alcohols and fatty amines are preferably
used as the hydrophobic modifiers. These contain, for
example, a linear chain with at least 8, preferably at
least 12 carbon atoms, wherein crosslinked fractions are
also possible.
The amine value of associative thickeners is preferably 5
to 100, particularly preferably 10 to 90; the hydroxyl
2 ~ 66290
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value is 0 to 70, preferably 5 to 50. Naturally, ln
accordance with the conventional definition, the amine
value and OH value in the present description each relate
to mg of KOH per g of solid resin.
The various modules are stable in storage. Two or more
identical or different modules may be mixed to yield novel
storage-stable combined modules. Various effect and/or
colour modules may, for example, be mixed together.
The invention provides an advantageous process for the
production of various types of aqueous coating compositions
based on a standard binder, which process is characterised
in that a supply of each of the modules A) to E) according
to the invention is prepared and optionally stored, the
modules being separately prepared, and, when required, the
modules necessary for a particular application, such as for
example the quantities required to achieve a desired colour
tone or effect, of the prepared modules A) are mixed with
B) and/or C) and/or D) and/or E).
The aqueous coating compositions are produced by simply
mixing the binder modules A) with the colour modules B),
the effect modules C), the crosslinking modules D) and/or
the rheological modules E). Depending upon the selection of
the second necessary modular component or the further
possible modular components, various coating compositions
may be produced, such as base lacquers, single-coat topcoat
lacquers or clear lacquers.
Thus, for example, in order to produce clear lacquers, at
least one binder module and at least one crosslinking
module are mixed together. The binder modules used here are
preferably based upon a binder combination of cationic
(meth)acrylic copolymer resins and cationic polyester-
polyurethane resins. The preferred resins for this purpose
are those described above for the binder module A).
21 66290
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Particularly preferred poly(meth)acrylate resins have a
number average molecular weight (Mn) of 4000-50000, a
hydroxyl value of 60-175 mg KOH per g of solid resin and a
glass transition temperature of -20 to +75C. The amine
value is preferably 20-100 mg KOH per g of solid resin. The
crosslinking module preferably contains those crosslinking
agents based on blocked or unblocked polyisocyanates and/or
melamine resins with at least two groups per molecule which
are reactive towards amino and/or OH groups.
In order to produce clear lacquers, the modular system
according to the invention preferably contains at least one
rheological module. It is possible by means of a separate
rheological module subsequently to influence rheology
during production of the coating composition. If the
rheological agents are, for example, already contained in
the binder module A), then the rheology of the complete
coating composition is predetermined by the binder. The
rheological agents used here are preferably
polyurethane-based cationic associative thickeners, as have
already been stated in the description of the rheological
module.
The modular system may also contain transparent pigments,
for example transparent titanium dioxide, for the
production of clear lacquers. The transparent pigments may
be contained in a separate colorant module or in one of the
other modules present.
A modular system according to the invention for the
production of, in particular, effect base lacquers,
preferably consists of a binder module A) based on a binder
combination prepared from a cationic poly(meth)acrylate
resin and a cationic polyurethane resin and an effect
module C) with a (meth)acrylated polyurethane dispersion as
the binder and optionally a colour module B) with
preferably one or more cationically stabilised polyester-
2 1 66290
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urethane resins as the binder together with a rheological
module E) with preferably polyurethane-based cationic
associative thickeners. The resins preferably used here are
described in the binder module.
In order to produce, in particular, single-tone base
lacquers and single-tone, single-coat topcoat lacquers, the
modular system according to the invention may preferably
contain at least one binder module A) based on a binder
combination prepared from a cationic poly(meth)acrylate
resin and a cationic polyesterurethane resin, at least one
colour module, wherein the colour module preferably
contains the cationic polyurethane paste resins described
above, and a rheological module based on polyurethane-based
cationic associative thickeners. A crosslinking module may
be present in both the single-tone base lacquers and the
single-tone, single-coat topcoat lacquers, which module
contains, for éxample, melamine resin crosslinking agents
and/or blocked polyisocyanates. Preferred resins are
described above in the binder and rheological modules.
The modules may be added in any desired sequence during
production of the coating compositions. Preferably,
however, the modules with the highest viscosities and the
highest proportions by volume are introduced initially.
After mixing, application viscosity may be established by
adding deionised water.
The coating compositions produced from the modular system
according to the invention preferably have a solvent
content of below 20 wt.%, particularly preferably of below
10 wt.~.
The complete coating compositions may be applied directly
after mixing. They may, however, also be stored for longer
than 12 months. In the case of room temperature
~ ~ 2166290
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crosslinkable two-component coating compositions, the
crosslinking module must, however, be separately stored.
A particular advantage of the modular system according to
the invention is that the most varied coating compositions
may be prepared in a simple manner from standard
components. The present invention also provides these
coating compositions.
The quantities listed below may, for example, here be used
in the production of the coating compositions according to
the invention. The quantities relate to the solids contents
from the individual modules, which make up the total solids
content of the coating composition (100 wt.%).
When producing aqueous effect base lacquers, the solids
content from the binder module is preferably 10 to 99,
particularly preferably 40 to 95 wt.%; the solids content
from the colour module 0 to 40, preferably 0 to 30 wt.%;
the solids content from the effect module preferably 0.01
to 50, particularly preferably 1 to 30 wt.%; the solids
content from the crosslinking module 0 to 40, preferably
0 to 25 wt.% and the solids content from the rheological
module preferably 0.01 to 50, particularly preferably 1 to
40 wt.%. In order to achieve application viscosity, the
aqueous effect base lacquer is preferably adjusted to a
total lacquer solids content of 10 to 55 wt.%, particularly
preferably of 12 to 40 wt.%.
When producing single-tone aqueous base lacquers, the
solids content from the binder module is preferably 5 to
60 wt.%, particularly preferably 8 to 50 wt.%; from the
colour module preferably 1 to 60, particularly preferably
3 to 50 wt.~; from the crosslinking module 0 to 40,
preferably 0 to 25 wt.% and from the rheological module
0 to 40, preferably 1 to 30 wt.%. The solids content of the
single-tone aqueous base lacquer is adjusted to application
- ~ 21 66290
'_
- 31 -
viscosity with a solids content of preferably 10 to
60 wt.%, particularly preferably of 12 to 45 wt.%.
In order to produce single-coat topcoat lacquers, the
solids content from the binder module is preferably 5 to
60 wt.%, particularly preferably 8 to 50 wt.%; the solids
content from the colour module preferably 0.5 to 60 wt.%,
particularly preferably 1 to 45 wt.%; from the effect
module 0 to 50 wt.%, preferably 0 to 30 wt.%; from the
crosslinking module preferably 0.5 to 40 wt.~, particularly
preferably 1 to 3S wt.% and from the rheological module
0 to 40 wt.%, preferably 1 to 30 wt.%. At application
viscosity, the total solids content of the single-coat
topcoat lacquer is preferably 10 to 70 wt.%, particularly
preferably 12 to 50 wt.%.
When producing clear lacquers, the solids content from
binder module is preferably 15 to 90 wt.%, particularly
preferably 35 to 85 wt.%; from the colour module 0 to 20,
preferably 0 to 10 wt.%; from the effect module 0 to 10,
preferably 0 to 5 wt.%; from the crosslinking module
preferably 0.01 to 50 wt.%, particularly preferably 2 to
40 wt.%; from the rheological module 0 to 40 wt.%,
particularly preferably 1 to 30 wt.%. At application
viscosity, the total lacquer solids content of the clear
lacquer is preferably 10 to 80 wt.%, particularly
preferably 12 to 65 wt.%.
The aqueous coating compositions produced from the modular
system according to the invention may be applied using
conventional methods, for example by spraying. Curing may
proceed at, for example, between 20C and 140C.
A preferred option for application is to apply a base
lacquer produced with the modular system according to the
invention and, after a flashing-off stage at 20C-80C, to
apply a conventional clear lacquer or a clear lacquer
21 66290
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produced with the modular system according to the invention
using the wet-on-wet method and curing both layers
together.
The multicoat lacquer coatings obtained in this manner
satisfy today's conventional requirements for automotive
lacquer coating. They are suitable for automotive original
and repair lacquer coating, but they may also be used in
other sectors, for example for lacquer coating plastics,
wood or ceramics.
The modular system according to the invention consists of
individual storage-stable modules which may simply and
readily be mixed together. Low-solvent, aqueous coating
compositions with good long term storage stability may be
produced. Storage and production of the various coating
compositions, such as base lacquers, topcoat lacquers and
clear lacquers, are rationalised by means of a single
modular system. A particular advantage of the system
according to the invention and of the process according to
the invention is that the most varied coating compositions
may be prepared on the basis of standard modules.
The following examples are intended to illustrate the
invention in greater detail.
Production examples for binder
Production example 1:
966 g of ethoxypropanol are heated under inert gas to 100C
with a reflux condenser being used. Within a period of 4
hours, a mixture of 195.5 g of hydroxyethyl methacrylate,
599 g of butanediol monoacrylate, 592 g of n-butyl
methacrylate, 483 g of 2-ethylhexyl methacrylate, 439 g of
butyl methacrylate, 439 g of methyl methacrylate, 893 g of
styrene, 358 g of 3'-dimethylaminopropylmethacrylamide and
46 g of t.-butyl peroctoate is added. The temperature is
then maintained at 110C for 1 hour, 8.4 g of t.butyl
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peroctoate dissolved in 12.2 g of ethoxypropanol are added
and this operation is repeated one hour later. After 3
hours at 110C, the following intermediate values are
determined:
Solids content: 79.6 (30 minutes 150C)
Viscosity: 12.5 Pa-s (50~ in ethoxypropanol at
25C)
Production of the aqueous dispersion:
4 g of formic acid solution (50% in water) and 32.6 g of
ethylene glycol monobutyl ether are thoroughly incorporated
into 250 g of the aminoacrylate described above and 713.4 g
of completely deionised water are then added to produce the
dispersion. After 2 hours' stirring, a finely divided
aqueous aminoacrylate dispersion is obtained.
Characteristics:
Solids content: 20.4 wt.~ (60 minutes 150C)
Acid mEq: 21 mEq/100 g of solid resin
pH value: 6.5
Production example 2:
(Production example 1 in DE-A-4 011 633)
725 g of butoxyethanol are heated under inert gas to 110C
with a reflux condenser being used. Within a period of 3
hours, a mixture of 192 g of hydroxyethyl methacrylate,
137 g of butanediol monoacrylate, 288 g of glycidyl
methacrylate, 364 g of 2-ethylhexyl acrylate, 439 g of
butyl methacrylate, 439 g of methyl methacrylate, 90 g of
styrene and 44 g of azobisisobutyronitrile are added. Then,
after 1 hour at 110C, a solids content of 72.2 wt.~ is
measured and, after dilution to 60 wt.~ with butoxyethanol,
a viscosity of 2.14 Pa-s at 25C is measured. After cooling
to 50C, a mixture of 120 g of diethylamine and 201 g of
- ` ` 21 66290
- 34 -
isopropanol is added rapidly (1.10 mol of amine for
1.00 mol of epoxide). After 30 minutes, the temperature is
raised to 65C, maintained for 2 hours, then raised to 105
to 110C and maintained for 3 hours. After cooling to 80C,
isopropanol and excess amine are carefully removed by
vacuum distillation. Solids content is adjusted to
approximately 80 wt.% with butoxypropanol.
Intermediate value:
Solids content: 79.7~ (30 minutes 150C)
Amine value: 45 mg KOH per g of solid resin
Viscosity: 3.44 Pa-s (60% in butoxyethanol at
25C)
Production example 3:
855 g of a polyester polyol (produced from neopentyl
glycol, hexanediol and isophthalic acid with an OH value of
102 and an acid value 1) are mixed at approximately 45C
under inert gas with 138 g of methyldiethanolamine and
300 g of acetone in a reaction vessel with a stirrer,
internal thermometer, heater and reflux condenser. 410.5 g
of isophorone diisocyanate are then added and the
exothermic reaction is maintained at 80C by cooling and
heating until virtually no free isocyanate may any longer
be detected (NCO value less than 0.2). At 40C, 88.6 g of
lactic acid in 200 g of water are added and thoroughly
incorporated. 2902 g of completely deionised water are then
added to produce the dispersion. After 2 hours~ stirring at
room temperature, a finely divided polyurethane dispersion
is obtained.
; 2166290
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Final values:
Solids content: 34.2 wt.% (60 minutes 150C~
Acid mEq: 66 mEq/100 of solid resin
5 pH value: 5.6
Productian example 4:
912 g of a polyester (produced from adipic acid,
isophthalic acid, 1,6-hexanediol and neopentyl glycol with
an OH value of 113 and an acid value 1) are mixed at
approximately 45C under inert gas with 191 g of
methyldiethanolamine and 185 g of N-methylpyrrolidone in a
reaction vessel with a stirrer, internal thermometer,
heater and reflux condenser. 697 g of isophorone
diisocyanate are then added and the exothermic reaction is
maintained at 80C by cooling and heating until the NCO
value is approximately 3.3. After the addition of 185 g of
N-methylpyrrolidone, 184 g of hydroxyethyl methacrylate are
added and the temperature maintained at 60C until no free
isocyanate may any longer be detected.
At 40C, 74.1 g of formic acid in 152 g of water are added
and thoroughly incorporated. 2026 g of completely deionised
water are then added to produce the dispersion. After 2
hours' stirring at room temperature, a finely divided
polyurethane dispersion is obtained.
Final values:
Solids content: 44.0 wt.% (60 minutes 150C)
Amine value: 45 mg KOH
Production example 5:
30 g of the polyurethane dispersion from production example
4 are diluted with 2S g of completely deionised water and
21 6629~
- 36 -
heated to 80C. An emulsion prepared from 0.23 g of
hexanediol diacrylate, 0.45 g of lauryl acrylate, 2.0 g or
styrene, 1.2 g of ethylhexyl acrylate, 1,6 g of
hydroxyethyl acrylate, 3.1 g of n-butyl methacrylate and
0.4 g of azoisobutyronitrile in 14 g of the polyurethane
dispersion from production example 4 and 10 g of completely
deionised water is added over a period of 3.5 hours at
80C. This temperature is then maintained for one hour,
then an emulsion of 0.1 g of azoisobutyronitrile in 2.3 g
of polyurethane dispersion from production example 4 is
added and the temperature maintained at 80C for one more
hour. A finely divided dispersion with the following
characteristics is o~tained:
Solids content: 31.8 wt.% (1 hour 150C)
Amine value: 32 mg KOH/g
pH value: 5.1
Production example 6:
909 g of a polycaprolactone diol with an OH value of 112
and an acid value of 1 is mixed under inert gas at
approximately 45C with 141.5 g of methyldiethanolamine in
a reaction vessel with a stirrer, internal thermometer,
heater and reflux condenser. 442.5 of isophorone
diisocyanate are then added and the exothermic reaction is
maintained at 80C by cooling and heating until virtually
no free isocyanate may any longer be detected (NCO value of
less than 0.2).
96.5 g of lactic acid in 152 g of water are added at 60C
and thoroughly incorporated. 2759 g of completely deionised
water are then added to produce the dispersion. After 2
hours' stirring at room temperature, a finely divided
polyurethane dispersion is obtained.
21 66290
~- - 37 -
Final values:
Solids content: 33.5 wt.% (60 minutes 150C)
Amine value: 45 mg ROH
5 Acid mEq: 75 mEq/100 solid resin
Production ex2mple 7:
682.5 g of a polyester diol (produced from neopentyl
glycol, cyclohexanedicarboxylic acid and isophthzlic acid
with an O~ value of 49 and an acid value of 1.3), 27 g of
pentaerythritol, 148.3 g of dodecanol and 508 g of
N-methylpyrrolidone are mixed under inert gas at
approximately 45C with 153 g of methyldiethanolamine in a
~5 reaction vessel with a stirrer, lnternal thermometer,
heater and reflux condenser. 52g g of isophorone
diisocyanate are then added and the exothermic reaction is
maintained at 80C by coolinq and heating until virtually
no free isocyanate may any longer be detected (NCO value of
less than 0.2).
118 g of formic acid (50% in water) are added at 50C and
thoroughly incorporated. 2828 g of completely deionised
water are then added to produce the dispersion. After 2
hours' stirring at room temperature, a finely divided
polyurethane dispersion is obtained.
Final values:
Solids content: 32.3 wt.% (60 minutes 150C)
Acid mEq: 84 mEq/100 g solid resin
pH value: 5.2
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Production examples for the individual modules:
Binder modules:
The binder modules are produced by thoroughly stirring
together their constituents:
Binder module I:
Constituents:
172.0 g binder (according to production example 5)
28.5 g binder according to production example 3
234.5 g binder according to production example 1
30.0 g completely deionised water
Binder module II:
Constituents:
70.4 g binder according to example 1
5.3 g binder according to example 3
4.3 g co~pletely deionised water
Binder module III:
Constituents:
47.3 g binder according to example 2
5.2 g binder according to example 3
3.2 g completely deionised water
2 1 66290
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- 39 -
Binder module IV:
Constituents:
31.3 g binder according to example 5
24.5 g binder according to example 2
2.5 g binder according to example 3
1.2 g ethylene glycol monobutyl ether
13.0 g completely deionised water
Rheological module I:
100 g of the binder according to example 7 are mixed with
2 g of ethylene glycol monobutyl ether and 10 g of
lS compl-etely deionised water.
Effect modules:
For production of the effect modules, the particular effect
pigment is initially introduced into a vessel and solvents,
wetting additives and binders are then thoroughly stirred
in.
Effect module I:
Constituents:
8.4 g of a conventional commercial aluminium paste
suitable for aqueous base lacquers with 65%
aluminium
0.8 g of an aluminium wetting additive based on organic
phosphoric acid derivatives
4.9 g ethylene glycol monobutyl ether
2.0 g N-methylpyrrolidone
4.5 g n-butanol
8.0 g binder according to production example S
The module has a water content of 8.9 wt.%.
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Effect module II:
Constituents:
12.8 g of a conventional commercial iriodine pigment
Z.7 g of a conventional commercial wetting additive
2.7 g n-butanol
1.1 g N-methylpyrrolidone
8.0 g binder according to production exzmple 5
The effect module has a water content of 9.3 wt.%.
Colour modules:
Blue colour module:
- 41.1 g binder according to example 6
1.1 g of a conventional commercial dispersion auxiliary
0.6 g ethylene glycol monobutyl ether
33.9 g of a conventional commercial blue copper
phthalocyanine pigment
10.5 g completely deionised water
Red colour module:
Constituents:
44.0 g binder according to example 6
1.6 g of a conventional commercial dispersion auxiliary
2.9 g ethylene glycol monobutyl ether
34.5 g of a conventional commercial red pigment
17.1 g completely deionised water
- 41 _ 2 1 66290
Black colour module:
Constituents:
48.9 g binder according to example 6
1.2 g of a conventional co~mercial dispersion auxiliary
5.0 g ethylene glycol monobutyl ether
13.5 g of a conventional commercial carbon black pigment
15.6 g completely deionised water
The pigment is ground in the stated mixture with an
appropriate apparatus.
Crosslinki~g module:
Crosslinking module I (melamine resin mixture):
6.5 g Cymel 373
3.5 g completely deionised water
Crosslinking module II:
9.7 g Luwipal 012
2.0 g of a conventional commercial isocyanate blocked
with butanone oxime and based on isophorone
diisocyanate
1.3 g ethylene glycol monobutyl ether
Crosslinking module III:
3.0 g Cymel 327
7.0 g completely deionised water
Crosslinking module IV:
3S
8.1 g Setamin US 138
6.9 g ethylene glycol monobutyl ether
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Production of aqueous ~ase iacquers
Storage-stable, aqueous effect lacquers are produced by
uni~ormly mixing together the modules stated in the table.
They are adjusted to the desired application viscosity with
water. The stated values are parts by weight.
Effect base lacquers:
A B C D
Silver Silver Silver Blue
metallicmetallic metallic
Binder module 1 68.9 71.2
Binder module IV 72.6 72.6
Effect module 1 15.0 15.0 15.0
Effect module ll 20.1
Rheological module 18.5 9.0 10.5 10.5
Crosslinking module 1 10 10
Blue colour module 4
Si~gle-tone ba~e lacquerQ & single-tone, single-coat
topcoat lacquers:
A B C D E
Blue Black Red Red Topcoat
lacquer
Binder module ll 80.6 76.5 76.2 75.5
Binder module lll 55.7
Rheological module 110.4 9.6 7.8 10.4 10.5
Crosslinki"g module lll 10 1 1
81ue colour module 10.5 13.4
Red colour module 12.45 15.9
Black colour module 14.23
Aqueous single-tone lacquers are obtained by mixing the
above-stated components. They are adjusted to the
particular desired application viscosity with water.
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They may be used as aqueous base lacquers and single-tone,
single-coat topcoat lacquers.
Aqueous clear lacquer
s
A B C D E
Binder module ll 76.2 76.5 76.2 76.5 76.5
Thickening module I9.0 9.6 9.0 10.2 9.6
Crosslinking module 1 10 6.5
Crosslinking module ll 13.2
Crosslinking module lll 10.0
Crosslinking module IV 15.0 10.5
