DE1519144B2 - COATING AGENTS IN THE FORM OF Aqueous SOLUTIONS - Google Patents

Description

3 4

b) 35 to 85% of one or more alkyl esters of the tall, show excellent gloss, are excellent acrylic acid with 1 to 8 carbon atoms in the ester alkyl waterproof and have a high surface hardness,
rest, by polymerizing 1 to 25% acrylic

. ,,., "", ",",. ,,. ,, amide or methacrylamide methylol ethers will be

c) 5 to 40% styrene, vinyl toluene or "-Methyl- _{5 polymeris} ^ _(" self-crosslinking ", that is, it can be

^stvrol > · suitable substrates without the addition of other crosslinking agents

d) 3 to 15%, preferably 5 to 12%, of a copoly agent are made insoluble. Preferred are merizable α, / 9-unsaturated carboxylic acids, such as ^the methyl ethers and, of these, that of acrylic, acrylic or methacrylic acid, amide. The methylol methyl ethers allow one for

ίο practical purposes already sufficient networking

e) 3 to 3O ° / o of a copolymerizable or ether, at temperatures from about 12O ⁰ C. They are not available in the ester with at least one free hydroxyl f _re i _s methylol after.

group such as acrylic or methacrylic acid hydroxy- The methylol ethers allow surprising-

propyl or ethyl ester or trimethylol propane _we j _se as opposed to the free Methylolverbindun-

diallyl ether, ₁₅ gene polymerization at temperatures above 80 ⁰ C,

f) 0 to 10% acrylic or methacrylamide, *> even above 100 ⁰ C, even in the presence of acid

(Acrylic or methacrylic acid), without that already during the polymerization gel formation through crosslinking

occurs in an anhydrous organic solvent. By polymerizing at temperatures above

Temperatures of about 80 to 120 ⁰ C, preferably 20 80 or 100 ⁰ C are low-viscosity polymer

100 to 12O ⁰ C, obtained in the presence of a catalyst poly solutions. The methylol ethers also allow

merized and the organic solvent after or in the presence of water and only partially neutral

with the addition of water and less than one equivalent of carboxyl groups, distilling off the solvent

valent, based on the solvents contained in the polymer, without the polymer

Carboxyl groups, ammonia or an amine with 25 is wetting.

a boiling point below 170 ^° C. in whole or in part The methylol ethers of acrylic or methacrylamides

distilled off. are preferably used in amounts of about 10 to 20%

The invention relates to coating agents used in. Higher proportions than 20% increase the

Form of aqueous solutions of ammonium or brittleness, without the chemical and solvent

To improve amine salts of copolymers from methylol medium resistance. In the case of significantly

vaten of the acrylic or methacrylic acid amide, acrylic ringer amounts go the solvent resistance

acid esters, aromatic vinyl compounds, a, /? - un- back. However, in special cases

saturated carboxylic acids, copolymerizable ethers, amounts down to 1% are useful,

or esters with at least one free hydroxyl- The monomers coming to the polymerization

group and possibly acrylic or methacrylic mixtures contain up to 85%> preferably up to

acid amide, characterized in that the copoly- 75%> Acrylic acid ester (b) and styrene (c) as compo-

merisate from polymerized ^ units of components without self-crosslinking groups. The relationship these two components are aligned with each other

a) 1 to 25% of a methylol ether of acrylic or according to the desired polymer properties. A Methacrylamides, 40 higher percentage styrene increases the hardness, water and

_M " _v ".,. ,, ",. , Solvent resistance of the stoved polymer.

b) 35 to 85% of one or more esters of acrylic _{reduces the} water solubility of the non-acidic product with 1 to 8 carbon atoms in the ester _{alkyl radical} . _By acrylic acid ester with small

c) 5 to 40% styrene, vinyl toluene or α-methyl-alkyl radical (methyl, ethyl) is the water solubility styrene, 45, while esters with a larger alkyl radical (such as

Butyl or 2-ethylhexyl acrylate) the elasticity of the

d) 3 to 15% acrylic acid or methacrylic acid, increase films. The one used to regulate the hardness of the

e) 3 to 30% of a copolymerizable ether or polymer serving styrene portion causes ^{a reduction in the viscosity of the counter-ester with at least one free hydroxyl s} f * ™ other hardening monomers such as Megruppe 50 thyl methacrylate

aqueous polymer solutions.

f) 0 to 10% acrylic or methacrylamide The water solubility of the polymers is primarily

Line through the polymerisation from 3 to 15%

consists. Acrylic or methacrylic acid guaranteed. Preferred

The coating compositions according to the invention result in 5 to 12% · The required amount depends on

after stoving at temperatures of about 120 the amount of the hydrophilic otherwise still present

water copolymer components which are particularly durable up to 200 ^{° C. on surfaces.} Amounts over about 15%

solid coatings with excellent surface hardness are generally of little advantage because the higher

Scratch resistance and high gloss. Compensate for water solubility through stronger cross-linking

It is surprising and has to be sated from known processes, which in turn results in the polymer

it cannot be inferred that the mono-films mentioned are too brittle. It also determines the amount of

Merenkombination under the conditions mentioned polymerized carboxylic acid very strongly the viscous

film-forming, gel-free polymer solutions of lower sity of the aqueous solutions. For amounts over about

Can produce viscosity, the viscosity is stable 15%, the solutions are a solid content

and their films at the same low temperature 65 from 35 to 40% too viscous. For amounts below about 5%

can be baked in like the films made of poly- you can no longer get any of the above mono-

merisates with free methylol groups. The crosslinked, merenzusverbindungen polymer solutions that

d. H. burned-in films, e.g. B. form homogeneous films as coatings on homogeneous films; then polymer

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satdispersions, their film formation at room temperature solvents. The addition of water is measured in such a way that

temperature depends on the polymer composition. that dieiösung when the solvent is distilled off

By polymerizing 3 to 30% of a product, it is neither too concentrated nor too dilute,

Free hydroxyl-containing monomers are A.n Ammonia or amine are less than

the elasticity, chemical and solvent- 5 1 equivalent, based on that in the polymer

Resistance of the polymers improved. In addition, existing carboxyl groups are added, preferably

results in a better combinability with others no more than 0.5 equivalents. To be favoured

Coating resins such as formaldehyde melamine condensate amines, which have a boiling point below about 170 ^° C.

tion products. Usually 5 to 10%> sitting is sufficient for this. Examples include: triethylamine, tri-

but higher additives can also be advantageous, io propylamine, Ν, Ν-dimethylethanolamine, N-methyl

if the amount of polymerized acrylic or ethanolamine.

Methacrylic acid should be kept as low as possible. The removal of the solvent can be carried out by an-AIs Monomers containing hydroxyl groups are combined distillation, by steam distillation or fertilize like acrylic acid or methacrylic acid hydroxyl by blowing off with air or nitrogen, propyl ester or ethyl ester suitable. Most commonly, the solvent becomes azeotropic as a binary trimethylol propanediallyl ether droplet mixture has distilled off with water. It is also grasslands. This connection makes gloss and possible to add a third component that is with Scratch resistance of the polymer films clearly improves solvent and water a ternary azeotropic improvement, mixed forms. The distillation can be carried out batchwise

Acrylic or methacrylic acid amide can optionally 20 natural or continuous, as well as both under

can be polymerized in amounts of up to 10%. This normal pressure as well as under reduced pressure

is particularly recommended when performing with the poly.

merisate solution a pigmented or colored mi-After distilling off the solvent (

research is to be produced. The presence of a low viscosity, film-forming, cloudy to almost

Acrylic or methacrylamide in the polymer improves a clear polymer solution that is free from gel particles.

The dispersibility of difficult-to-wet The viscosity of 35 to 40% solutions is

Pigments such as B. carbon black or aluminum bronze. maximum about 1000 cP, what a polyelectrolyte

For the preparation of the polymers, the monosolution is unusually low. The pH of the

Merging with a suitable anhydrous organic solution is 6.6 to 7.4, usually 7.2 to 7.4 ^{, at 20 ° C.}

Solvent mixed and after addition of a poly 30 Since these are aqueous polymer solutions

merization catalyst and optionally displacer is not dispersions, are to achieve

In the air by nitrogen to 80 to 120 ⁰ C, pre-homogeneous films of high gloss no additions of

preferably 100 to 12O ⁰ C, heated. external plasticizers, superplasticizers or similar

In general - auxiliaries are required for 100 parts of monomers. In special cases

about 80 to 400 parts of solvent, preferably 100 35 but an addition of water-soluble solvents such as

applied to 150 parts. Suitable solvents glycol or similar may be appropriate,

are preferably saturated aliphatic alcohols such as The aqueous polymer solutions can on the

Propyl alcohols or butyl alcohols, various substrates such as iron, aluminum,

aromatic hydrocarbons such as toluene or xylene zinc, copper, brass used in the paint industry

and other organic liquids such as dioxane, 40 customary application methods such as spraying, dipping

Glycol ethers or esters, as well as solvents or brushes can be applied. The films show

mix can be used. Appropriately selects a selected one of the substrate materials mentioned.

if a solvent or solvent mixture was used, adhesion was drawn. ._

Which at the desired polymerization temperature is just as excellent is the adhesion to others ί

temperature boils, which means that the temperature can be controlled.

rend the polymerization is facilitated. Epoxy resins, polyurethanes, phenolic resins or on

The main polymerization catalysts used are already existing layers of the same material,

organic per compounds such as benzoyl peroxide, tert.- In a particular embodiment, the material is

Butyl perbenzoate, tert-butyl peroxide and hydroperial applied to steel sheets by electrophoresis,

oxide, cumene hydroperoxide, paramenthane hydroperoxide 50 The polymer solutions are suitable for this

and azo compounds such as azodiisobutyronitrile are particularly good because they have no emulsifiers, none

suitable. other foreign electrolytes and only relatively little

Contain the usual carboxyl or carboxylate groups which regulate the molecular weight. Here-

Substances such as dodecyl mercaptan or tetrachloride do not interfere with electrophoresis

or tetrabromomethane can also be used. 55 electrolysis on.

The polymerization can also be carried out in this way. The clear or pigmented films are through

the fact that the polymerization in a part of the stoving at 120 to 200 ⁰ C, preferably 140 to

The monomer solution starts and most of the 180 ^° C. is converted into an insoluble state. the

Monomers (solution) during the polymerisation of films then have excellent resistance

continuously admits. 60 compared to water, table salt and soda solution. Self

The polymerization is generally after about 5 after 50 hours of storage in these media is no-

finished within 20 hours. noticeable change. The sheen of the films is

The gel-free organic polymer obtained is outstanding, so that according to the invention

solutions are water and ammonia or a prepared polymer solution built up paint

Amine added. The amount of water depends on the 65 mixes very well for decorative single-coat paintwork.

desired polymer concentration in the z. B. on household appliances, ice boxes,

providing aqueous solution, after which distillation washing machines and the like are suitable,

process and according to the organic used. Although the aqueous polymer solutions for

I 519 144

generation of coatings can be used without the addition of crosslinking agents, it is In principle, however, it is possible to use formaldehyde condensation products to further improve the film properties, z. B. urea or melamine to be used.

The aqueous polymer solutions as described above can be used to produce homogeneous coherent films of high gloss can be used, without the addition of superplasticizers, external plasticizers or similar auxiliaries are necessary.

For special cases, such as B. to change the conductivity of the solutions for use as electrophoresis varnish, however, water-miscible solvents, such as glycols or the like. Are added.

The polymer can now be mixed with water-soluble formaldehyde condensation products. Melamine or urea-formaldehyde resins are preferred for this purpose used.

The aqueous solution of the polymer can either alone or in combination with the formaldehyde resins mentioned Applied to a wide variety of substrates such as iron, aluminum, zinc, copper, brass are made using the application processes commonly used in the paint industry. Liability on the said Subsurface materials is very good. But it is just as excellent on other layers of leaks, the z. B. can be based on alkyd resins, epoxy resins, polyurethanes, phenolic resins, or on existing layers of the same material. In a particular embodiment, this is Material applied to steel sheets by electrophoresis. The composite material according to the invention is particularly suitable for this process, as it is soluble in water without the mediation of emulsifiers and contains only a small proportion of carboxyl groups. This causes one to occur in electrophoresis disturbing electrolysis occurs only to a minor extent.

It is used for many purposes - especially z. B. to protect light and non-ferrous metal - a clear coat of paint is required, but mainly pigmented or colored layers are used. The pigments generally used in the paint industry, such as titanium dioxide, iron oxide, chromium oxide, zinc sulfide, carbon black, aluminum bronze, etc., as well as fillers of the silica or sulfate type, possibly also phthalocyanine dyes, thickeners, etc., can be used for this purpose. For special anti-corrosion coatings, anti-corrosive pigments such as B. zinc chromate, lead chromate, strontium chromate, can be used. They are incorporated in mills, rollers or pan mills using the method customary in the paint industry. The clear or pigmented films formed by spraying, dipping or brushing are by baking at 120 to 18O ⁰ C, preferably from 160 to

ίο 180 ° C, for 30 minutes in the insoluble state convicted. The films have a remarkably good resistance to water, common salt or Soda solution. Even after 100 days of exposure to these agents, there is no film determine change. The gloss of the clear and pigmented paint film is excellent, so that the lacquer mixtures composed according to the invention are very good for decorative single-layer lacquers, z. B. for household appliances, ice boxes, washing machines, etc., are suitable.

The aqueous polymer solutions are particularly suitable for producing coatings on metals, however, they can in principle also be used for covering or coating other substrates, such as Wood, paper, textiles, glass, plastics, ceramic materials, leather and others. be used. pre-condition it is only that the polymer film applied to a substrate is sufficient by heating insoluble, d. H. can be made sufficiently resistant to water and possible solvents.

The invention is further illustrated by the following examples.

The percentages and weights in the examples relate to weight, if not otherwise stated.

The following comparison shows the superiority

of the coating agents according to the invention versus a product of Belgian patent 637 264.

It was a copolymer according to Example 1 of

present application - hereinafter referred to as coating agent A - produced. For comparison was Example 1 of the present application is repeated with the change that instead of the acrylic acid amide-N-methylol methyl ether the N * [(3-oxabutoxy) methyl] acrylic acid amide

[CH ₃ -OCH ₂ -CH ₂ -OCHp-NH-CO-CH-CH ₂ ]

was used (coating agent B). From the coating agents A and B according to Example 1 the present Registration lacquer films are produced and the technical lacquer properties of these films are determined. The comparative tests produced the following results:

Paint film properties A. very good B. 309 528/488 the coating agent White rough, pinpricks 3 to 4 H. White 8.0 4H 1 5.4. . after 30 days. 2 unchanged after 12 days without cracks Detachment of the paint film unchanged Cracking unchanged unchanged unchanged

shine

hue

Surface hardness *)

Elasticity *) ..

Adhesive strength *)

Water resistance *)

Bending test at 180 ⁰ C *)

Resistance to ethyl acetate (I ')

Toluene (1 ')

*) Test methods according to the guidelines given in Table 1.

As can be seen, the paint films obtained according to the invention not only show a better gloss, but also a higher elasticity, water resistance and adhesive strength. _f

5 Example 1

a) Manufacture of polymers

In a glass polymerization vessel equipped with a stirrer, thermometer, reflux condenser and dropping funnel, a mixture of 90 parts of n-butanol, 30 parts of butyl acrylate, 10 parts of ethyl acrylate, 20 parts of styrene, 12 parts of acrylic acid, 10 parts of hydroxypropyl methacrylate, 18 parts of acrylamide methylol methyl ether and Given 1.5 parts of tert-dodecyl mercaptan. After the air has been displaced by nitrogen, the mixture is heated to boiling (about HO ⁰ C). A solution of 2 parts of 70% cumene hydroperoxide in 10 parts of n-butanol is then added over the course of 2 hours. After a further 10 hours at the boiling point, the polymerization is complete. The clear polymer solution obtained contains 49.2% polymer and has a viscosity of 4300 cP.

50 parts of water and 0.36 parts of ammonia (= 0.13 equivalents) are added to the resulting polymer solution added as a 10% aqueous solution. The mixture is heated to about 100 ° C. with stirring and cooked through Introducing steam the butanol '· driven off. The remaining aqueous mixture is with ammonia or dimethylethanolamine adjusted to a pH value of 7 to 7.4, including a total of about 0.5 equivalents to be needed. At a polymer concentration of 35.5%, the solution is cloudy, gel-free a Brockfield viscosity of 1180 cP. (If more amine is added, a practically perfectly clear solution.)

b) Use

The aqueous polymer solution is diluted with water to a solids content of 30%, adjusted to a pH of 7.4 with triethylamine and then sprayed onto stainless steel and aluminum sheets. After flashing off V2 ündigem ^st at room temperature, the injection molded plates in 90 ° C preheated to about 80 drying cabinets are inserted. It is then further heated to 160 ° C and baked ¹ J ₂ hours at this temperature. Clear, light films with a fault-free surface are obtained. The hardness and scratch resistance as well as the elasticity and adhesive strength are excellent (see also Table 1 in Examples 2 to 6).

Table 1 Composition of the polymers and properties of the partially pigmented films produced therefrom

Composition of the monomer mixture

Butyl acrylate

Ethyl acrylate

2-ethylhexyl acrylate

Styrene

Acrylic acid,

Acrylamide methylol methyl ether

Methylol acrylamide

Acrylamide

Hydroxypropyl methacrylate

Trimethylol propane diallyl ether

Viscosity of the organic solution, cP

Concentration of the organic solution,%

Viscosity of the aqueous solution, cP

Concentration of the aqueous solution,%

pH of the aqueous solution

Degree of pigmentation

shine

hue

Surface hardness +)

Elasticity ++) ^:

Adhesion +++);

Water resistance ¹ ):

Bending test ² );

*) Pencil hardness according to DIN 46453. **) According to Erichsen according to DIN 53156 .. ** ♦) Cross-cut according to DIN 53151. *) u = unchanged.
² ) Rapid bending around a sharp edge: + without cracks, - cracks.

2 example 4th 5 1 37 3 41 19th 30th 7th 40 8th 7th 10 - 6th - 18th - 20th - 20th 20th 20th 10 16 8th 10 12th 17th 15th 18th 17th 18th - 18th - 9 10 9 - 5 2500 5 1960 2400 4300 49.0 1840 49.5 49.3 49.2 90 49.5 34 100 1180 35.5 1540 34.5 35.5 35.5 7.0 35.0 7.4 7.2 7.2 50% 6.9 50% 50% - emerged 50% emerged very very outstanding emerged outstanding Well Well pure outstanding pure pure pure White pure White White White 2 to White 3H 2H 3 to 3H 2 to 4H 7.7 3H 8.6 8.0 8.0 1 8.0 1 1 1 > 50 ^d 1 > 30 ^d > 30 ^a > 30 ^d 180 ° + > 20 ^d 180 ° + 180 ° + 180 ° + 180 ° +

1300 48.0 17 35.0 7.1 50%

very

Well

pure

White

2H

> 20 ^d 180 ° +

11 12

Comparative test of titanium dioxide rutile goods (corresponding to 50% on solid

Polymer calculated) by grinding on the

As described in Example 1, a polymer funnel mill is pigmented. The varnish solution obtained in this way, prepared from the same monomers, would now be diluted with water with the only difference that instead of 18 parts 5, a spray viscosity of 90 seconds in the DIN beaker of acrylamide methylol methyl ether corresponds to the equimolar amount of 4 -mm nozzle set. To prevent blistering when methylolacrylamide (16 g) is used. To avoid such burning, are also 74 g 49 _4/0 strength polymer solution in butanol has a visco-butyl glycol added. The aqueous paints are sität of about 2000 cP. As described in Example 1, an aqueous solution is then prepared therefrom on glass plates, steel sheets and aluminum. The panels sprayed with io and after semi-continuous venting pH 7 to 7.4 available solution is interspersed inserted with gel at room temperature in about 90 ⁰ C hot dry bodies and has a viscosity according to Brookfield ovens and then Temperatursteigevon 200 00OcP. By dilution with water tion burned to 16O ⁰ C. The necessary inputs and the addition of dimethylethanolamine is no clear the burning time at 16O ⁰ C is of V ₂ hour. Obtainable after removal or even almost clear solution. If the films are cooled according to their appearance, spreads on glass are divided from the cloudy solutions and the mechanical properties are measured, or metal sheets are carried out, one obtains inhomo- The results found are also divided into films with specks and one Listed in Table 1,
show restless course. Because of the very high .
viscosity, the films are extremely thin and 20 Example /
frothy. In the manner described in Example 1, an r, · · 1 becomes ₉ . F- polymer of 45 parts of butyl acrylate, 10 parts of ^{p D s} ethyl acrylate, 15 parts of styrene, 10 parts of acrylic acid,

In the manner described in Example 1, un- 5 parts and 15 parts of acrylamidomethylol methyl ether

using the 25 trimethylolpropane diallyl ether listed in the table above,

led monomer mixtures polymer solutions produced 100 parts of the 35% 'gene aqueous solution are with

and used for the production of coatings. 3.5 parts of a commercially available water-soluble metal

In all cases, gel-free amine-formaldehyde resin is added at pH 6.9 to 7.4, with 50% titanium dioxide

Obtained polymer solutions of low viscosity. The oxide, calculated on a solid binder, is pigmented and

for pH values of about 7 to 7.4 specified visco-30 after dilution to a spray viscosity of 90 "

sities can, if desired, be added to metal panels in a DIN cup with a 4 mm nozzle.

Ammonia or amines or glycol ether sprayed and applied by dipping onto iron rods,

alcohol levels are increased. After VgStundigem baking at 16O ⁰ C who

1000 g of the polymer solutions will have the following properties with 175 g of films:

Table 2
Characteristic data of the polymer solution and properties of the films

Viscosity of the organic solution 2300

Concentration of the organic solution 49.0

Viscosity of the aqueous solution 85

Concentration of the aqueous solution 35.0

pH of the aqueous solution 7.2

The appearance of the films is white, high-gloss, good flow

Surface hardness ++) 4 H

Elasticity ++) 6 to 7.8

Adhesion ++) 1

Resistance unchanged when stored in distilled water at 20 ^° C. after 70 ^d

3% saline solution at 20 ^° C. unchanged after 70 ^d

3% detergent solution at 2O ⁰ C after 70 ^d unchanged

Ethyl acetate unchanged after 5 minutes exposure time

Toluene unchanged after 5 minutes of exposure

Ethyl glycol acetate unchanged after 5 minutes exposure time

♦ *) For explanations, see Table 1.

Claims (4)

1 2 claims "-methacrylamide to produce and use water-soluble polymers. These polymers with 1. Coating agents in the form of aqueous solutions with "internal" crosslinking agents give harder and more elastic ammonium or amine salts of copolymers films at a relatively low baking temperature. B. 120 ⁰ C; Their aqueous solutions are already methacrylic acid amides, acrylic acid esters, aromatic vinyl compounds, α, / 3-unsaturated carbons, highly viscous and not free from gel particles, copolymerizable ethers or esters, because the free methylol groups react with at least one free hydroxyl group and already during production with crosslinking of the optionally acrylic or methacrylic acid amide, io polymer. For the same reason they are characterized in that the solution is also not viscosity-stable; that is, the copolymer of polymerized units of viscosity increases on storage. For the use of aqueous polymer a) 1 to 25 ° / ₀ of a Methyloläthers of acrylic solutions of the type described as a coating or methacrylamide, 15 for metals (stoving lacquers), it is necessary b) 35 to 85% of one or more esters that the solutions are practically free of extraneous electrolytes acrylic acid with 1 to 8 carbon atoms in the ester ^{such as} emulsifiers and inorganic and organic alkyl radicals, salts. This requirement is particularly important c) 5 to 40% styrene, vinyl toluene or «-Methyl- ^ enn the coatings are to be applied to metals _{by electrophoresis from aqueous stvro j so solution.} ,, ... '.,. ... ,,, ... It is known to produce solutions of this type, in- d) 3 to 15% acrylic acid or methacrylic acid, _{to which the polymerization of} acrylic acid or methacrylic acid e) 3 to 30% of a copolymerizable ether containing acrylic acid-containing monomer mixtures in an organ or esters with at least one free hygienic solvent using therein droxylgruppe, 25 makes soluble activators, then the f) 0 to 10% acrylic or methacrylamide polymer isolated from this solution and added to set of bases dissolves in water. After another consists. known processes, the solvent is distilled 2. Coating agent according to claim 1, characterized ge after the addition of water and bases, which indicates that component e) of the poly- 30 aqueous polymer salt solution remains,
merisats is trimethylolpropane allyl ether. When trying to produce methylol 3. Coating agent according to Claim 1, characterized in that the copolycyclic or methylol methacrylamide-containing that component b) of the polymer, these processes provide those mentioned above merisats an ester of acrylic or methacrylic acid highly viscous and crosslinked polymer (gel) entmit polyhydric alcohols is. 35 holding solutions. 4. Coating agent according to claim 1, marked from Belgian patent 637 264 are drawn in water by adding a water-soluble stoving enamels (ammonium salts) known as Melamine or urea-formaldehyde-condensate binder copolymerized units of N-oxidation product. alkoxymethylcarboxamides, ethylenically unsaturated 40 saturated carboxylic acids, ethylenically unsaturated carboxylic acids and at least one other mono- mers included. According to the information in this document such coating agents, such as the N-methylol alkyl ethers, should be used unsaturated carboxylic acids, further unsaturated It is known, with the addition of bases, water-soluble 45 saturated carboxylic acids and at least one other borrowed copolymers of acrylic and methacrylic acid components included in polymerized form, essentially in esters and copolymerizable «, ^ - unsaturated car- reference on storage stability, pigmentability and acids such as acrylic or methacrylic acid and their possible solids content are superior, if necessary, further non-reactive polymerizing The comparative experiments at the end of the description to establish connections. It is further- 5 ° however clearly demonstrate the superior other- knows, these polymers as a coating agent for the application properties of the N-methylol various materials such as textile fabric, paper, containing alkyl ether carboxamide units Use wood, glass and metal. The polymerizing agents. However, films remain even after heating to higher levels. As the examples show, they are easily pigmentable, Temperature, e.g. B. to over 12O ⁰ C, water-soluble or 55 low viscosity and storage-stable. highly swellable with water. This sensitivity Emulsion polymerization processes are naturally unsuitable for exposure to water and other solvents due to the addition of crosslinking or crosslinkable agents such as soluble polymers, which are free from external electrolytes and emulsifiers. Insoluble condensation products from urea or urea give them very high molecular weight polymers, the melamine and formaldehyde or epoxides are very greatly reduced when they are converted into water-soluble aqueous salts. The with the help. such mixtures result in solutions of too high viscosity,
From water-soluble polymers and formaldehyde foreign electrolyte-free, gel-free aqueous polymer condensation products or epoxides, low viscosity solutions in the form of their salts, however, coatings have insufficient surface areas if a monomer mixture is used
hardness and scratchability. They're also a little 65 elastic. . a) 1 to 25% acrylic or methacrylamide methylol It has therefore also been proposed to use ether, preferably acrylamidomethylolmethyl- by copolymerization with methylol acrylic or ether,