DE2262463C2 - Coating agents - Google Patents

Description

1. at least one of the monomers: hydroxyethyl and hydroxypropyl esters of acrylic and methacrylic acid,

2. at least one of the momomers: acrylic acid, methacrylic acid and itaconic acid and

3. at least one further monomer that has neither reactive groups nor suitable for crosslinking Contains carboxylic acid groups.

^{2 (1} 2. Coating agent according to claim 1, characterized in that the monomers, which are neither reactive

Groups still contain carboxylic acid groups, alkyl esters of acrylic and methacrylic acid, styrene, vinyl toluene,

Methylbenzene, acrylonitrile, vinyl chloride, vinylidene chloride and vinyl acetate are. 3. Coating agent according to claim 1 or 2, characterized in that it contains the crosslinking resin

a weight ratio of copolymer to crosslinking resin of 60:40 to 85: IS. ^;; 4. Coating agent according to claim 3, characterized in that it is the crosslinking Harz.in one

Contains weight ratio of interpolymer to crosslinking resin of 75:25 to 85:15.
S. coating agent according to one of claims 1 to 4, characterized in that the crosslinking resin

a condensate of formaldehyde and urea, melamine or thiourea or a lower alkyl ether of such a condensate is.
6. Coating agent according to claim 5, characterized in that the crosslinking resin is a metal / formaldehyde condensate which is etherified with butanol and has a petroleum ether tolerance of at least 10 ml / g.

7. Coating agent according to claim 6, characterized in that the crosslinking resin has a petroleum ether tolerance of at least 15 ml / g .
^ 8. Coating agent according to one of claims 1 to 7, characterized in that it is in addition to

dispersed polymer contains a further film-forming polymer which is in solution in the entire organic liquid of the coating agent.

The invention relates to a coating agent based on dispersions of copolymers in organic liquids and in particular to coating agents of the thermally curable type.
Thermally curable coating agents based on solutions of mixtures of alkyd resins and metal

J5 min / formaldehyde condensates (M / F) are generally known. They are used in particular in the automotive industry. So-called “metal effect paints” have also been used there for years, with which a different light reflection effect, which depends on the viewing angle, can be achieved on car bodies. The effect is enhanced by the incorporation of a small amount of fine metal flakes, such as B. Aluminum flakes. In the coating agent, which optionally also contains a colored pigment. To the maxl-

To achieve a metallic effect, the metal flakes must be oriented parallel to the surface of the coating, so that the amount of light reflected by the covering changes with the viewing angle and the surface is shiny and appears bright when looking straight at the surface, and appears darker and less bright, if you look at it at an acute angle. However, it was found that metallic effect paints on the Based on solutions of thermally curable alkyd / M / F compositions, insufficient permanent adhesion

v tlgkelt have. To eliminate this disadvantage, metallized, thermally curable paints were used on the basis Developed from combinations of acrylic resins and M / F condensates in solution.

These metallized thermally curable acrylic / M / F solution paints have the advantage that they are with a higher solids content can be applied than the metallized thermoplastic paint systems that are also widely used in the automotive industry. This makes it possible to have a satisfactory

<· '< Coating gaps can be achieved in the three-layer process that is usually used in spray systems for car bodies. The thermally curable solvent-based paints, however, still leave something to be desired, because in metallized systems they do not produce such a pronounced metallic effect as thermoplastic paints. The reason lies in the acrylic polymer used in the thermosetting paints because it has a lower molecular weight than the acrylic polymer used in the thermoplastic compositions

f. ^s is used. As a result, the film is fluid and mobile after application, so that the aluminum flakes can easily orientate themselves statistically. In addition, there is very little shrinkage of the film on stoving, which could lead to a reorientation of the metal parallel to the surface.

Ϊ This disadvantage can in principle be eliminated by using a larger number of coverings with mil

a lower solids content. Strong economic arguments against such a procedure and operational concerns.

DE-OS 22 05 171 relates to coating compositions consisting of a dispersion of particles of a mixed polymer from ethylenically unsaturated monomers in an inert organic liquid in which the dispersed Polymer is insoluble, but contains between 40 and 75% by weight of a solvent for the polymer, wherein the dispersion is stabilized by a polymeric stabilizer, which is an anchoring component that is associated with the particles of the disperse polymer, and a solvated component, which is a stabilizing results in steric shell around the particles, and wherein the stabilizer additionally kovaleni to the disperse Polymer is bound and wherein the coating agent may also contain customary paint additives can.

It has now been found that coating agents, as described in DE-OS 22 05 171, particularly are useful as coating agents if the film-forming disperse polymers are certain mixed polymers, which contain both crosslinkable reactive groups and acidic groups, and if in the coating agent a certain crosslinking resin is incorporated which is capable of reacting with the reactive groups in the disperse polymer is capable.

The subject of the invention is therefore a coating agent of the type known from DE-OS 22 05 171, which is characterized in that the coating agent additionally contains a crosslinking resin with reactive methylol or alkoxymethyl groups in a weight ratio of copolymer to crosslinking resin of 50: SO to 90:10 and that the disperse copolymer has been obtained from

1. at least one of the monomers: hydroxylethyl and hydroxypropyl ester of acrylic and methacrylic acid,

2. at least one of the monomers: acrylic acid, methacrylic acid and itaconic acid and

3. at least one further monomer which has neither reactive groups nor carboxylic acid groups suitable for crosslinking contains.

The coating compositions according to the invention have favorable properties. In particular, have metallized Lacquers of this type do not have the disadvantage of a poorer metallic effect, which is found in the corresponding solvent lacquers, but nevertheless maintaining or even improving the advantages of the latter will.

The anchoring component of the polymeric stabilizer is included in the coating compositions according to the invention associated with the disperse polymer and the stabilizer is also covalently bound to the disperse polymer. Such polymeric stabilizers are described in detail in GB-PS 12 31614, for example.

By the term "solvent" is meant a liquid that contains only the polymer particles that make up the represent disperse phase, dissolve or swell. The nature of the solvent thus depends on the composition of the disperse polymer. In general the solvent will be of a polarity similar to that the disperse polymer. Correspondingly, nonsolvers have a different polarity.

When the disperse polymer is a polar material, such as e.g. B. Polymethyl methacrylate by inclusion a smaller amount of monomer units with reactive and acidic groups has been modified 1st, then the following solvents can be used:

1. Ester

Ethyl acetate, n-butoxyacetate, ethyl lactate, ethyl benzoate, 2-ethoxyethyl acetate, 2-butoxyethyl acetate, 2- (2-n-butoxyethoxy) ethyl acetate, Ethylene glycol diacetate, 1,3-butylene glycol acetate, 2,2,4-trimethylpentanediol-1,3-monolsobutyrate.

2. Ketones

Acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methoxyhexanone, mesltylo oxide.

3. Alcohols

2-ethylbutanol, 2-methoxyethanol, 2- (2-n-butoxyethoxy) ethanol, 3,5,5-methylhexanol, dlacetone alcohol.

4. Ether

Diethylene glycol diethyl ether, ethylene glycol di-n-butyl ether, tetrahydrofuran.

5. Aromatic hydrocarbons
Toluene, xylene, tetralin.

6. Various solvents

Dimethyl sulfoxide, dimethylformamide, 2-nitropropane, morpholene, chloroform, ethylene chloride.

If, on the other hand, the disperse polymer is non-polar, as is the case, for example, if the predominant If the monomer component consists of styrene, then the following solvents can be used:

1. Ester

Ethyl acetate, butyl acetate, 2-ethoxyethyl acetate.

2. Ketones

Acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl isoamyl ketone, disobutyl ketone, isophorone, cyclohexanone, Mesity oxide.

3. Hydrocarbons

Heptanes, hexanes, octanes, decanes, benzene, toluene, xylene, tetrahydrofuran, cyclohexane.

4. Various solvents
2-nitropropane, dimethylformamide.

The total organic liquid must be a non-dissolver for the disperse polymer to be Maintain dispersion stability. The non-solvent surface of the organic liquid must only have a low tendency to dissolve or swell the disperse polymer.

Examples of non-dissolvers In the case where the dispersed polymer is poler, the following are:

1. Alcohols

Methanol, ethanol, n-propanol, n-butanol, 2-butoxyethanol, cyclohexanol.

2. Hydrocarbons

Heptanes, hexanes, octanes, decanes and higher aliphatic hydrocarbons, ethylbenzene, Trlmetljylbeni'i'i zole and higher substituted alkylbenzenes.

Examples of nonsolvents In the case where the disperse polymer is nichipolar, the following are:

1. Alcohols Methanol, ethanol, 2-methoxyethanol, 2- (2-n-butoxyethoxy) ethanol, dlacetone alcohol, cyclohexanol.

The copolymer present in the coating agent according to the invention contains both reactive groups, with which it can react with the crosslinkable resin, as well as carboxylic acid groups that cause the crosslinking reaction catalyze. The proportion of monomers which contain reactive groups is preferably in the range of S

2 to 25% by weight, based on the total monomers used.

Suitable monomers which do not contain reactive groups or carboxylic acid groups are alkyl esters of Acrylic and methacrylic acid, such as. B. methyl methacrylate, butyl methacrylate, ethyl acrylate and 2-ethylhexyl acrylate, as well as styrene, vinyl toluene, vinyl benzene, acrylonitrile, vinyl chloride, vinylidene chloride and vinyl acetate. Their proportion in the mixed polymer can even outweigh the other monomers.

: <The dispersions used in the coating compositions according to the invention can be obtained by In der Technik Known processes can be produced in which the polymer is in particulate form in the inert organic liquid is dispersed in the presence of the stabilizer, so that the necessary associative forces and creating additional covalent bonds between the stabilizer and the particles. To the The crosslinking resin is then added to the resulting dispersion. Preferably the disperse polymer is

. "> by polymerizing the monomer or monomers in an organic liquid in which the polymer Is insoluble, obtained in the presence of the stabilizer as described in GB-PS 1,231,614. The composition of the organic liquid used in the actual preparation of the polymer dispersion does not necessarily have to be the same as that of the entire organic liquid of the Coating agent, provided that the first-mentioned liquid is one in which the dispersed polymer is insoluble. Certain components of the total organic liquid can thus be added, after the dispersion has been made. For example, it can be advantageous to use the dispersion in one to produce liquid medium, which is predominantly or under certain circumstances even completely from a non-solvent for the polymer, whereupon the necessary proportion of the solvent for the polymer is added later will.

The crosslinking resin incorporated into the coating composition according to the invention can be any of the commercially available resins which contain reactive methylol or alkoxymethyl groups, in particular condensates of formaldehyde with nitrogen-containing compounds, such as. B. urea, melamine and thiourea, and the lower alkyl ethers of such condensates. Melamine / formaldehyde condensates in which a considerable proportion of the methylol groups are etherified by reaction with butanol are particularly suitable

The ratio of mixed polymer to crosslinking resin in the coating agent is between 50: SO and 90:10. The exact ratio to be used will depend on the properties required in the finished coating away. A preferred range, weight ratio, that gives a good balance of properties. is from 60:40 to 85:15. A property of particular importance in coating agents for automotive applications

5i> fertilize in countries with high atmospheric pollution. Is resilience of the finished cured coating against strong inorganic acids, such as. B. sulfuric acid. It was found that a valuable improvement in this property is obtained, at the same time also a a satisfactory level of other coating properties is maintained when a ratio of interpolymer to crosslinking resin is used which is in the vicinity of the higher end of that given above

Range, in particular in a range from 75:25 to 85:15.

A wide variety of crosslinking resins of the general types mentioned above can be used in accordance with the invention. For example, if the resin is an etherified melamine / formaldehyde condensate, then the degree of etherification of the methylol groups with butanol can be varied. Regarding the already mentioned property of acid resistance of the finished cured coating was found to be a

wi a high degree of etherification is preferable. This can be defined as a petroleum ether tolerance of at least 10 ml / g, preferably at least 15 ml / g. Determined by a method based on ASTM Dl 198-55, which consists in taking a sample of the etherified '. Melamine / formaldehyde condensate at 20 to 25 "C titrated with petroleum ether with a boiling moose from 100 to 120 ° C until it becomes cloudy. In addition to the main disperse film-forming polymer, the coating agents can contain an additional

Λ5 ches film-forming polymer that is dissolved in the total organic liquid of the coating agent Is. This additional polymer can be a mixed polymer which is simultaneously with the disperse polymer or it can be added as a preformed polymer that is unlike the disperse polymer Is soluble in the organic liquid in which the dispersion is made. It can also be a poly

act more that is insoluble in the organic liquid in which the main polymer dispersion is made it is initially also dispersed therein, but then when added to the liquid of certain Components of the total organic liquid of the coating agent goes into solution, as has already been done has been described. Finally, it can also be an added preformed polymer that is used throughout the organic liquid of the coating agent is soluble, although it is insoluble in the organic liquid in which the main polymer dispersion is produced. The amount of the additional soluble polymer Im Coating agent may or may even be comparable to the amount of insoluble disperse polymer go beyond this without departing from the scope of the invention and without the advantages of the invention get lost.

The coating compositions according to the invention can optionally be used in an unplmented form for production can be used on clear toppings. But you can also use any of the usual paint additives included, such as B. Pigments, fillers and plasticizers.

The coating compositions according to the invention have remarkable advantages over known thermal ones curable coating agents. This is especially the case when the coating agents are used for spray treatments are, and if the ingredients of the organic liquid medium are selected so that the Most or all of the non-dissolver inventory due to volatilization during the spraying process get lost. The material which reaches the substrate then contains swollen polymer particles and residual active solvent, the latter aiding the flow of the particles. Because such particles have practically no flow properties, the tendency of the coalescing film is to sink in and to run greatly reduced compared to conventional thermally curable solution paints. The lower one Solvent content of the coalescing film also increases the likelihood of occurrence of Evaporation craters is reduced. The production of strong orders is facilitated. So can a dry one Coating thickness of 0.1 mm can be produced with just two orders. This is with three orders to compare to a conventional paint.

After the coating compositions according to the invention have been applied to the substrate by spraying or by other techniques are the gradual coating from the mixed polymer with the help of the reactive groups in the The polymer and the crosslinking resin are crosslinked by baking the coating, one in the art for thermally curable resins usual manner, usually at 100 to 140 ° C. Optionally, can also lower temperatures can be used if the crosslinking resin is sufficiently reactive. The crosslinking reaction is, as already stated, by the carboxylic acid groups in the disperse film-forming polymer are present, catalyzed, but if desired, the coating agent can also contain an additional catalyst included for this purpose.

The coating agents according to the invention are particularly suitable as a basis for thermally curable metallic effect paints, In which a small amount of metal flake is incorporated, as discussed above. The invention Coating agents meet the three basic requirements for production to a high degree a coating with a distinct metallic effect, namely: (1) rapid setting of the coating after applying to the substrate so that the flakes are immobilized; (2) high shrinkage of the Coating to induce orientation of the metal flakes parallel to the surface of the coating; and (3) good foot behavior and good leveling during baking, so that it has a smooth, shiny appearance will.

The invention will now be further illustrated by the following examples, in which the parts are expressed by weight are.

example 1
Manufacture of a stabilizer

A reactive precursor is made by condensing a polyester by self-condensation from 12-hydroxystearic acid to an acid value of approximately 31 to 34 mg KOH / g nonvolatiles has been made with glycidyl methacrylate.

Methyl methacrylate, glycidyl methacrylate and the reactive precursor are used in weight ratios 46: 5: 49 copolymerized in a solvent mixture consisting of 2 parts of ethyl acetate to 1 part of butyl acetate consists. More butyl acetate is then added to make an interpolymer solution having a solids content of approximately 33%.

The following mixture:

Mixing polymer solution (as above) 98.782 parts by weight

Methacrylic acid 0.440 parts by weight

Dimethyl coconut amine 0.057 part by weight

p-tert-butyl catechol 0.006 part by weight

is heated to reflux (approximately 11Γ C) until the acid value is less than 1 mg KOH / g non-volatile substances amounts to. Continue to be

p-nitrobenzoic acid 0.683 parts by weight

Dimethyl coconut amine 0.032 parts by weight

toeeceben. and the mixture is refluxed until the acid value is again less than 1 mg KOH / g

of non-volatile substances. In this way a solution of a polymeric stabilizer is obtained which contains polymer-soluble double bonds. S.

Preparation of a polymer dispersion 'h

(': ■

The film-forming polymer is a mixed polymer of styrene, methyl methacrylate, butyl methacrylate, 2-ethyl- 'ß, hexyl acrylate, hydroxyethyl acrylate and methacrylic acid. | ίί

10.08 parts hexane and 10.08 parts of heptane are charged into a kettle and heated to reflux temperature i§ (ca. 8O ⁰ C.). Then a mixture of 1.67 parts of methyl methacrylate, 0.125 parts of azodilsobutyronltrll
id and 0.48 parts of the polymeric stabilizer solution described above are added rapidly and the reactants are held at reflux temperature for 25-30 minutes. A dispersion of
Seed particles formed from polymethyl methacrylate. This vaccine dispersion is then used during a tent room
of 3 hours at reflux temperature the following mixture:

Styrene 11.49 parts

Methyl methacrylate 5.08 parts

Hydroxyethyl acrylate 3.83 parts

Butyl methacrylate 7.42 parts

2-ethylhexyl acrylate 7.67 parts

i » methacrylic acid 1.00 part

Stabilizer solution (as described above) 11.08 parts

primary octyl mercaptan 0.12 parts

Azodilsobutyronltrll 0.26 parts

- ■ 5 introduced. When the addition is complete, the mixture is refluxed for an additional 30 minutes, whereupon 0.32

Divide azodilsobutyronltrll in six equal servings 30 minutes apart while continuing to ||

flow can be added. After the sixth addition, the batch is refluxed for 2 hours, then i «

a further 0.05 part of Azodilsobutyronltrll are added, and finally the batch is for a further 2 hours

held at reflux to complete the polymerization. The approach obtained, which is both polymer p

: · ■■> in dispersion as well as polymer in solution, is then cooled to 65 ° C, whereupon the following mixture £;

added: ft

White spirit 3.50 parts g

aromatic hydrocarbon (boiling point 190 to 210 ° C) 3.50 parts t \

Isopropanol 1.00 part |;

n-butanol 4.58 parts g;

After cooling to 30 ° C, the batch is given with ψ _:

! ■■ < Isopropanol 2.88 parts %

n-butanol '4.63 parts |; i

aliphatic hydrocarbon (boiling point 100 to 12O ⁰ C) 4.80 parts iff

aromatic hydrocarbon (bp 16ObIs 180 ° C) 4.37 parts * S

diluted. The dispersion obtained has the following properties: W,

Solids content 42 to 43%

reduced viscosity 0.24 to 0.28 dl / g 1

Acid value 16 to 18 mg KOH / g g

? ii Viscosity 2.5 to 3.5 Stoke / 25 "C. fy

The above viscosity value shows in comparison to the viscosity of a corresponding mixture which does not contain polymer g

contains that the product contains polymer in solution in addition to polymer in dispersion. gi

Manufacture and application of a metallized lacquer U

The following ingredients are mixed: Ifi

Aluminum flake paste
Ii highly butylated melamine / formaldehyde resin, 67% solution in butanol / xylene

Then slowly stir

Polymer dispersion (as described above)

6 <highly butylated melamine / formaldehyde resin, 67% solution in butanol / xylene

Isopropanol
Butanol
Xylene

1.2 Parts % 2.45 Parts I. H 48.15 Parts «J 20.60 Parts Cj 6.8 Parts "§ '■ 6.8 Parts i 6.8 Parts

aliphatlscher hydrocarbon (bp. 100 to 12O ⁰ C) 6.8 parts

linear polydlmethylslloxane (2% solution in xylene) 0.1 part

admitted. Before application, this lacquer is applied in a ratio of 4 parts of lacquer to 1 part of thinner with the following mixed solvent

Acetone 50 parts

2-ethoxyethyl acetate 30 parts

aliphatic hydrocarbon (boiling point 100 to 120 ° C) 12 parts

Ethylene glycol diacetate 8 parts

diluted.

The diluted paint is sprayed onto a plate in two passes. A coating thickness of 0.1 mm is achieved without sagging occurring and without the coating running. The coating elapses air drying, and then 30 minutes at 127 ⁰ C baked to a hard glossy coating is obtained which has an excellent metallic effect and shows no formation of evaporation craters.

If the application is repeated under overloading, so that a coating 0.15 mm thick is built up is, then a good, even metallic effect is still achieved.

Example 2

Production and application of a covering lacquer
The following mixture is made by stirring together in the order given

Pigment Mill Base 20.95 parts

Polymer dispersion (as described in Example 1) 38.50 parts

highly butylated melamine / formaldehyde resin, 67% solution in butanol / xylene 18.75 parts

Isopropanol 3.75 parts

n-butanol 6.00 parts

aromatic hydrocarbon (bp 160 to 180 ° C) 5.70 parts

aliphatic hydrocarbon (boiling point 100 to 120 ° C) 5.75 parts

linear polydimethylsiloxane (2 x 1 solution in xylene) 0.05 parts

manufactured.

The coating agent obtained is diluted with the same solvent and in the same ratio as is described above for the metallized paint, after which it is then applied by spraying in the manner described above. With a double application, a coating with a thickness of 0.1 mm is obtained without sagging and without the coating running. When baking for 30 minutes at 127 ^° C., a hard, glossy coating is obtained which is free from the formation of evaporation crates.

Example 3

Manufacture and application of an acid-resistant metallized paint
The following ingredients are mixed by stirring in the order shown:

Aluminum flock paste

highly butylated melamine / formaldehyde resin, petroleum ether tolerance > 15 ml / g,

67% solution in butanol / xylene

Phthalocyanine blue pigment grind base

Dloxazine Violet Pigment Mill Base

Polymer dispersion (as described in example 1)

highly butylated melamine / formaldehyde resin (as above) Isopropanol

linear polydimethylsiloxane (2% solution in xylene)

Before application, the coating agent is diluted in a ratio of 4 parts lacquer to 1 part thinner with the following solvent mixture: <

Acetone 50 parts

2-ethoxyethyl acetate 30 parts

aliphatic hydrocarbon (boiling point 100 to 120 ° C) 12 parts

Ethylene glycol diacetate 8 parts

1 / IC 1 tilt. 4.35 Parts 2.53 Parts 0.12 Parts 73.70 Parts 7.50 Parts 6.75 Parts 3.50 Parts 0.10 Parts

The lacquer is applied by spraying and then baked as described in Example 1. On this catfish a hard, shiny coating is obtained which has an excellent metallic effect and has a better acid resistance than the coating of Example 1, when it is tested by exposing it to a dilute sulfuric acid with a specific gravity of at 20.degree. C. for 24 hours 1.2 is exposed,
ί The loss of gloss and color change are determined visually.

Example 4

A polymer dispersion is produced by reacting the following constituents with one another will:

Portion I hexane 12.96 parts

Heptane 12.96 parts

Portion 2 methyl methacrylate ^{2 '54 parts}

ι? Azodlisobutyronitrile 0.16 parts

Stabilizer solution (as described in Example 1) 0.61 parts

n-octyl mercaptan 0.02 parts

Portion 3 hydroxyethyl acrylate 6.47 parts

Methacrylic acid 1.23 parts

2 "styrene 14.11 parts

Butyl methacrylate 9.53 parts

2-ethylhexyl acrylate 8.85 parts

Methyl methacrylate 6.53 parts

Stabilizer solution (as described in Example 1) 14.25 parts

2 ^ζ Atodllsobutyronltril 0.51 parts

n-octyl mercaptan 0.13 parts

Serving 4 methyl isobutyl ketone 9.06 parts

Azodiisobutyronitrile 0.48 parts

^{i (|} Portion 1 is charged into a reaction vessel equipped with a stirrer and a reflux condenser, and then heated to reflux temperature (about 80 ° C) Portion 2 is added rapidly and the reactants are maintained at reflux temperature for 30 minutes 25th A dispersion of inoculum is formed. Portion 3 is then added to this inoculum dispersion, 1/8 of which is added at a constant rate during the first hour of addition and the remaining 7/8 are added with

- ^ added at a constant rate during the following 3 '/ ₂ hours.

After the addition has ended, the reaction mixture is refluxed for a further 30 minutes. Then Portion 4 is introduced into the reaction mixture maintained at reflux with a steady rate over 3 '/ ₂ hours. The reaction mixture is refluxed 2 hours after the addition of portion 4 has ended and then cooled to 65.degree.

• 4 "The reaction product, which contains both polymer in dispersion and polymer in solution, is then diluted with the following solvent mixture:

White spirit 5.3 parts

aromatic hydrocarbon (bp 190 to 220 ° C) 5.3 parts

Isopropanol 4.0 parts

n-butanol 11.0 parts

aliphatic hydrocarbon (boiling point 100 to 120 ° C) 4.1 parts

aromatic hydrocarbon (bp 160 to 180 ° C) 3.7 parts

* 'The dispersion obtained has the following properties:

Solid content 41 to 42%

reduced viscosity 0.25 to 0.28 dl / g

Acid value 15 to 17 mg KOH / g

5i viscosity 2.5 to 4 stokes / 25 ° C.

The above viscosity value, when compared with the viscosity of the corresponding mixture, shows that contains no polymer that the product contains polymer in solution in addition to the polymer in dispersion.

A metallized lacquer is prepared from the above dispersion by adding the following ingredients in the mixed with each other in the order given:

high-butylated melamine / formaldehyde, petroether-gloss more than 15 ml / g,

6796 solution in butanol / xyiol 9.76 parts

Phthalocyanine Blue Pigment Mill Base 2.39 parts

'■' Dioxazine Violet Pigment Mill Base 0.11 part

Isopropanol 8.42 parts

Xylene 1.96 parts

Ailphatic petroleum hydrocarbon (boiling point 100 to 120 ° C) 4.21 parts

linear polydimethylsiioxane (2% solution in xylene) 0.05 parts j |

Aluminum flakes ^ asle 6.84 parts |

Polymer dispersion (as described above) 66.26 parts g

Before application, this varnish is mixed in a ratio of 3 parts by volume of varnish to 1 part by volume of thinner ■> |

Dilu.it, the diluent having the following composition: |

Acetone 50 parts §

2-ethoxyethyl acetate 30 parts

aliphatic hydrocarbon (boiling point 100 to 120 ° C) 12 parts ■■ ' Ethylene glycol diacetate 8 parts

The diluted paint is sprayed onto a plate in two passes. A coating thickness of s

0.1 mm achieved without the coating running or sagging. The coating is in the air i

left to dry and then ^{baked for 30 minutes at 127 0} C, a hard glossy coating with a ¹ ^ I

good Meta'lieffekt, good solvent resistance and without the formation of evaporation craters conservation J

will. t

Example 5

2 ' I.

A stabilizer solution is prepared as follows:

Methyl methacrylate, glycidyl methacrylate and the reactive precursor from Example 1 are ^{copolymerized at 80 to 85 C} in a weight ratio of 45: 6: 49 in butyl acetate, so that a mixed polymer solution with a solids content of 48 to 50% is obtained. The following mixture

Interpolymer Solution (as above) 63.143 parts

Methacrylic acid 0.440 parts

p-tert-butylpyrocatechol 0.006 parts ι

p-nitrobenzoic acid 0.683 parts

Dimethylethanolamine 0.089 parts.

is heated to reflux temperature (approximately 130 ° C) until the acid value is less than 0.9 mg KOH / g non-volatile Substances. Then 35.639 parts of butyl acetate are added, so that a solution with a solids content of 33% of a polymeric stabilizer containing polymerizable double bonds is generated.

A polymer dispersion is prepared according to the procedure of Example 4, except that instead of the ^ Stabilizer solution of Example 1 an equal amount of the stabilizer solution described above is used, and that portion 3 of the ingredients used in Example 4 is replaced by the following mixture:

Hydroxyethyl acrylate 10.74 parts

Methacrylic acid 0.95 part - "

Styrene 12.78 parts

Butyl methacrylate 9.53 parts

2-ethylhexyl acrylate 6.20 parts

Methyl methacrylate 6.52 parts

Stabilizer solution (as described above) 14.25 parts ■> -

Azodiisobutyronltrll 0.51 parts

n-octyl mercaptan 0.13 parts

The diluted dispersion obtained has the following characteristics:

Solids content 41 to 43%

reduced viscosity 0.25 to 0.28 dl / g

Acid value 16 mg KOH / g

Viscosity 4 to 5 poles / 25 ⁰ C.

When compared with the viscosity of the corresponding mixture, the above viscosity value shows which does not contain any polymer that the product in addition to the polymer in dispersion also polymer in solution contains.

A metallized coating is made of the above dispersion in the manner described in Example 4, with the same other ingredients are used and where quite the same amounts beibehal- ■ <> ten are.

The paint obtained was diluted and sprayed on in the same white as in Example 4. There were similar results as in Example 4 were obtained.

Claims (1)

Patent claims: 1. Coating agent, consisting of a dispersion of particles of a mixed polymer of athylenlsch unsaturated monomers in an inert organic liquid, in which the disperse polymer is insoluble, but which contains between 40 and 75% by weight of a solvent for the polymer, the dispersion stabilized by a polymeric stabilizer, which is an anchoring component that associates with the particles of the disperse polymer and a solvated component that is a stabilizing steric Shell results around the particles, and wherein the stabilizer is additionally covalently attached to the disperse polymer Is bound and wherein the coating agent may also contain customary paint additives in can, characterized in that the coating agent additionally contains a crosslinking resin with reactive methylol or alkoxymethyl groups in a weight ratio of copolymer to be crosslinked Contains resin from SO: SO to 90:10 and that the disperse copolymer has been obtained from