DE2144135A1 - Electrically depositable aqueous polymer preparation - Google Patents

Description

1st September 1971. H / P (370), 4772

PPG. INDUSTRIES, INC ₁ PITTSBURGH, PA. 15222 »V. St. A. ELECTRICALLY DEPOSITABLE AQUATIC POLYMER PREPARATION

This invention relates to an electrodepositable aqueous polymer preparation in dispersion form and a method for electrical deposition of such a preparation.

US Pat. No. 3,403,088 discloses aqueous dispersions of coating compositions described that can be applied by electrical deposition. These preparations contain a at least partially neutralized acrylic copolymer and an amine-aldehyde condensation product. The acrylic interpolymer contains a hydroxyalkyl ester in polymerized form an unsaturated carboxylic acid, an unsaturated acid and at least one other ethylenically unsaturated monomer. Although these materials are excellent materials for electrodeposition, it has been found that not in all cases when the deposition conditions are high error-free films can be obtained. If z. For example, electrical deposition creates coatings on irregular surfaces should be, such as B. lateral seams of steel cylinders and similar steel materials, it can happen that the If the deposited film cures, the coating will flow and the film will be too thin or even at an overlapped seam no film is formed at all, leaving the metal unprotected

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exposed to corrosion. In order to counter these dangers, one has in such places, z. B. at sioh overlapping Seams, relatively thick films deposited using films greater than 0.0254 mm (one mil) and generally even greater than 0.0508 mm (two mils) thick became.

With such relatively thick films, problems have arisen in that in the area passed through the vertical surface the overlapped seam and the lowest horizontal · surface of the overlapped seam is defined and where the top pull is the largest Has thickness, bubbles appear and become trapped, thereby spoiling the appearance of the film and most importantly but the strength and durability of the film in this area is weakened.

Similar problems are also encountered with the deposition of films 0.0381-0.0508 mm thick on horizontal substrates occurred.

It has now been found that the mixed polymer of a hydroxyalkyl ester of an unsaturated carboxylic acid, an unsaturated car-: acid and at least one other ethylenically unsaturated Monomers of a certain molecular weight in combination with an amine-aldehyde condensation product result in electrodepositable coating compositions which prevent the occurrence of bubbles in Eliminate or at least largely eliminate relatively thick films reduce, this improvement also occurring when the paint compositions for depositing films are overlapped Seam areas used as they are used when dividing steel cylinders by overlapping welding of steel plates or similar steel materials are created.

The coating compositions of the invention particularly include an acrylic copolymer containing from about one to about 20% by weight of a hydroxyalkyl ester of acrylic acid, methacrylic, acid or another alpha, beta-fithylenically unsaturated

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Contains carboxylic acid. These esters can be mixed with the Acid esterified alkylene glycol obtained or you can prepare them by reacting the acid with an alkylene oxide. In the copolymer with such a hydroxyalkyl ester there is about one to about 25% by weight of an unsaturated carboxylic acid and at least one other ethylenically unsaturated Monomer that is liiechpolymerisbaren with the acid and the ester is, polymerized.

The preferred hydroxyalkyl esters in such acrylic Mixed polymers are esters of acrylic acid or methacrylic acid, in which the hydroxyalkyl group has up to about 5 carbon atoms contains, such as 2-Hydroxyäthylacryl * t, 2-Hydroxypropylacrylat, 3-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 3-hydroxypropyl "" th "acrylate, 4 ~ Hydroxybutyl methacrylate and mixtures of such esters. Man can also corresponding esters of other unsaturated acids, e.g. B. methacrylic acid, crotonic acid and similar acids with use up to about 6 carbon atoms.

In addition to the esters of unsaturated monocarboxylic acids, mono- or diesters of unsaturated dicarboxylic acids, used such as maleic acid, fumaric acid and itaconic acid be, at least one of the ester groups in these esters should contain a hydroxyl group. Such esters of unsaturated Dicarboxylic acids give the products specific properties. Examples of such esters include:

Mono (2-hydroxyethyl) maleate, mono (2-hydroxyethyl) fumarate, Bis (2-hydroxyethyl) maleate, Mono (2-hydroxypropyl) maleate, bis (2-hydroxypropyl) maleate, Mono (2-hydroxyethyl) itaconate, bis (2-hydroxyethyl) itaconate and 2-hydroxyethyl butyl maleate.

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As an unsaturated acidic monomer is used in the copolymers acrylic acid or methacrylic acid is preferably used, although other acids having up to about 6 carbon atoms are also used can be, such as B. the mono- and dicarboxylic acids mentioned above in connection with the esters. if a monoester of a dicarboxylic acid is used as the hydroxyalkyl ester this monomer can also represent all or part of the acid.

The remainder of the acrylic copolymer consists of one or more other ethylenically unsaturated monomers, the are copolymerizable with the ester and the acid. As such Monomers can e.g. B. the various alkyl esters of alpha, beta-ethylenically unsaturated dicarboxylic acids, alkyl acrylates and alkyl methacrylates, such as ethyl, methyl, propyl, Butyl, hexyl, ethylhexyl and lauryl acrylate and methacrylate and like esters having up to about 20 carbon atoms in the alkyl group. Vinyl aromatic hydrocarbons can also be used as such monomers can be used, being styrene, alpha-alkylstyrene and vinyl toluene are typical such monomers.

Other unsaturated monomers that can be used include monoolefinic and diolefinic hydrocarbons a, halogenated monoolefinic and diolefinic hydrocarbons, unsaturated nitriles, unsaturated amides, unsaturated acids and the like. Some specific monomers of these Type are z. B. ethylene, 1,3-butadiene, acrylonitrile, acrylamide, vinyl acetate, alpha-chlorostyrene, vinyl chloride, methyl crotonate, Allyl chloride and similar compounds.

Particularly suitable in the paint preparations according to the invention are mixed polymers with an average number molecular weight of at least 6,000, an average weight molecular weight of at least 15,000 and preferably an average number molecular weight of at least 7,000 and an average Weight molecular weight of at least 50,000.

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The upper limit of the molecular weight is not very high essential and is determined by practical considerations. However, it was found that mixed polymers or Resins should preferably have a number average molecular weight of less than 100,000.

These copolymers are obtained using conditions and catalysts which are conventionally used for the preparation of acrylic polymers. Usually z. B. used a catalyst that forms free radicals, and the polymerization temperature is generally between about 65 and 140 ⁰ C.

The acidic or acrylic mixed polymer should at least partially be neutralized, d. That is, all or some of the acidic carboxyl groups of the copolymer are neutralized should in order to obtain the properties desired for electrodeposition. Usually at least about 10% of the acidic groups are neutralized. This is done through implementation these groups achieved with a base, with the neutralization before or after the addition of the copolymer to the paint preparation can take place.

Various bases can be used for the neutralization and preferred are a substantial part of the acidic groups, e.g. B. about 50% or more, neutralized. As a neutralizing agent inorganic bases such as metal hydroxides, e.g. B. alkyl! Hydroxides or alkaline earth metal hydroxides, especially potassium hydroxide, can be used, but ammonium hydroxide or organic amines can also be used for neutralization. The in The base selected on a case-by-case basis and the extent of neutralization depends on the nature of the base used to prepare the copolymer Monomers and the other components of the coating composition.

Amines that can be used include alkyl amines, such as ethylene amine, propyl amine, dimethyl amine, dibutyl amine, cyclohexyl amine, Diisoamylamine, triethylamine, tributylamine and

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Tripropylamine; unsaturated amines such as allylamine; Arylamines, like aniline; Aralkylamines such as benzylamine; Alkarylamines, such as m-toluidine; cyclic amines such as morpholine and piperidine; Diamines such as hydrazine, ethylenediamine and piperazine. Also hydroxylamines, such as diethanolamine, diieopropanolamine, diethanolamine and the like are suitable.

In some cases, part of the neutralization is done with a Diamine and another part is accomplished with another base, or part of the neutralization is done with the-) term amines, such as aminoalkyl-alkanediols, e.g. B. 2-methyl-2-amino-1,3-propanediol, achieved.

The neutralization can be carried out by the neutralizing base mixed with the copolymer or with the preparation dispersed in water. One can Use aqueous solution or another solution of the base and, if necessary, can adjust the temperature during the neutralization increase slightly.

Together with the acrylic copolymers, the to about 50 wt .-% represents about 95 of the water-dispersed coating composition, the non-volatile portion of the mass from about 5 to 'about 50 wt .-% of one amine Aldehydkondensationsproduktes, a polyepoxide, or a Combination of these two.

The amine aldehyde condensation products used here are Aldehyde condensation products of melamine, urea, acetoguanamine or similar connections. They can be soluble in water or in organic solvents. Generally will used as aldehyde formaldehyde, although useful products can also be made with other aldehydes, such as acetaldehyde, crotonaldehyde, Acrolein, benzaldehyde, furfural and other aldehydes can be obtained. In general, melamine or urea are preferred is used, but other amines or amides containing at least one amino group can also be used.

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Such condensation products can ζ. Β. can be obtained from triazines, diazines, triazoles, guanidines, gruanamines and the alkyl and aryl derivatives of such compounds, including alkyl substituted, aryl substituted and cyclic ureas and alkyl substituted and aryl substituted melamines. Some examples of such connections are Ν, Ν'-dimethyl urea, benzyl urea, N, N '~ Ethylene urea, diazine diamide, formaguanamine, benzoguanamine, Ammeline, 2-chloro-4-, 6-diamino-1,3 »5-triazine, 3» 5-diaminotriazole, 4,6-diaminopyrrimidine, 2,4-, 6-triphenyltriamino-i, 3,5-triazine and the like

These aldehyde condensation products contain methylol groups or similar alkylol groups depending on the particular aldehyde used. Optionally, these can be methylol groups be etherified by reaction with an alcohol. For such a Various alcohols can be used for etherification, in particular monohydric alcohols and very preferably short-chain alcohols aliphatic alcohols such as methanol, butanol and the like.

The amide-aldehyde condensation products are obtained in well known ways Process by using acidic or basic catalysts and the conditions for temperature and time as well varies in a known manner. The aldehyde is often used as a solution in water or in an alcohol, and the condensation, Polymerization and esterification reactions can be carried out either one after the other or simultaneously.

The formulations of the electrically depositable preparations or compositions according to the invention can also be other customary ones Contain additives, such as solvents, antioxidants, surface active agents, superplasticizers and other materials, which are used to regard the properties of the product to improve its stability and its film formation.

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Although non-pigmented coatings are of great importance, the preparation can also contain pigments in the usual way.

Conventional tap water can be used in the formulation of the coating composition. However, since such water sometimes contains relatively large amounts of cations, this can result in a certain change in the properties of the coating composition during electrical deposition, although this generally does not call into question the feasibility of the process. These difficulties can be avoided if one distilled w th or deionized water used, "can get to the deionized water in a known manner using an ion exchange resin.

Although the coating compositions according to the invention by any known methods can be applied, ε. B. with a brush, by spraying or by application rollers, they are special suitable for electrical deposition. In the case of electrodeposition, these coating compounds are dispersed in water brought into contact with an electrically conductive metal anode and an electrically conductive cathode. That too Plating metal substrate is used as an anode and can any electrically conductive metal, such as iron, steel, aluminum, galvanized steel, phosphated steel, zinc, Copper and the like. When the electric current «wipe the The anode and the cathode over which the water-dispersed paint flows in contact with these electrodes becomes a deposited on the metal adhering film from the coating composition on the anode. Either direct current is used for electrical deposition or alternating current if appropriate equipment is used.

The conditions for the electrical discharges are the usual, as they are otherwise used in electrical deposition. The tension can fluctuate very much and can very much be low, e.g. B. one volt, or very high, e.g. B. 1000 volts

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~ 9 -

or even higher. Typically, however, it is between about 50 and about 600 volts. The initial current density is in usually between about 0.0001 to 0.0016 amps * re / cm (0.1 amps up to 15 amps per square foot) and generally takes during the electrical deposition of the film,

It is desirable to keep the pH of the preparation dispersed in water as low as possible. Vorzugswelse is that pH below about 10.0, however, this depends on the particular components used, both in terms of the aorylic Interpolymers as well as the other resinous materials and also on the extent of neutralization.

The coating compositions according to the invention can be different Substrates are applied to protective coating · for various Purposes to form. You are e.g. B. suitable as insulating films for electrically conductive metal objects. Their uniformity, their high dielectric strength and their durability are particularly advantageous for such use. It is also of great advantage that with their electrical Deposition a complete coating of the to be coated Surface, including sharp edges, corners, etc., is achieved; this factor is particularly important for insulating coatings.

Numerous coatings from these masses are also characterized by very strong adhesion to certain materlallen, where otherwise it is difficult to obtain firmly adhering coatings. It is known, for example, that soft aluminum, known in the art as ^M aluminum magnetic strip *, is usually very difficult to provide with a coating in a satisfactory manner. With the paint formulations according to the invention, however, coatings from these materials are satisfactorily obtained. Because of this combination of properties, the preparations according to the Irfinduag are particularly t & t the production of electrically insulated aluminum strips (strips which are to conduct current in certain applications of interest, are suitable.

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As has already been stated, the preparations according to the invention are particularly suitable for covering overlapped weld seams, whereby the presence of tiny bubbles, sometimes referred to as "microbubbles", is largely reduced or eliminated. The weld seam which can be coated with the preparations according to the invention can essentially be any desired weld seam made of a ferrous metal. However, the preparations of NaOH of the invention are particularly effective for transferring Siehen of overlapped weld seams, which are weld seams, wherein two metal pieces ψ with their edges in an overlapped Besiehung be welded. The paintworks according to the invention are particularly suitable for covering an overlapped seam, at | which welds through a combination of temperature and | Pressure is generated and not through. Fusion welding. In this \ connection is preferable because of% s over look end welding \

sewing referred to the US-PS 3 4-68 453, from the more detailed individual \

units can be taken from such welds. f

W As stated ready? Irde _5, the t »rechweißtβ metal any ferrous metal be °, but preferably is the iron-containing metal is a steel with a low carbon content, the surface of which has a protective coating.

This protective coating is advantageously a passive coating, z. B. a coating obtained with a chromate or phosphate or similar non-tinned steels, see e.g. B. U.S. Patent 3,11384-5 and JOURNAL OF ELECTROCHEMICAL SOOIETT, Electrochemical Technology, September 1% 9, pages 1299 to 1305. The protective coating on the ferrous material does not, however, need to be a passive plating, and ee can also be tinned Metals or metals with another corrosion-resistant coating can be used.

The coating compositions of the invention are typically cured after application by heating the coated article for 1/2 to 30 minutes at temperatures of 121 to 315 ° C (250 _% to 600 ° F) or higher temperatures.

, _._ .., _;; J? 0981 2/1633 _0R k3, nal

The preparations according to the invention are particularly suitable

around defects and impurities and especially bubbles in the; Reduce film if the films are cured quickly,

ie in times of less than 5 minutes at temperatures of \

above 149 ° 0 (300 ° F). |

the invention is illustrated in more detail in the following examples purifies.

Example I · ■

In a reactor 730 parts of Äthylenglykolmetnyläther J

(Methyl cellosolve) and 190 parts of isopropanol added, and the;

The mixture was heated to reflux. In the course of ι 3 hours was the following mixture of monomers containing 11 parts 2,2'-azobisisobutyronitrile, added:

Weight parts Butyl acrylate 1496 Styrene 680 Hydroxypropyl methacrylate 139 Methacrylic acid 408

After the addition was complete, 4.5 parts of tert-butyl peroxyisopropyl carbonate were added to 10 parts of ethylene glycol methyl ether added, and the reaction smell was under for 2 hours Heated to reflux. This step was then repeated twice, and the reaction was then terminated.

The product had a solids content of 75 * 4%, a viscosity of 785,000 cp. and an acid value of 73.5. j

Example II j

In a reactor 920 parts of the monoethyl ether were from Ethylene glycol cellosolve) and the reactor contents were heated almost to boiling (130 - 140 ° C).

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ORIGINAL INSPECTED

It was the following mixture of monomers, which was 54.4 parts Containing di-tertiary butyl peroxide, added over the course of 3 hours under reflux cooling:

Parts by weight Butyl acrylate 1496 Styrene 680 Hydroxyethyl methacrylate 1J6 Methacrylic acid 408

After the addition of the monomers was complete, a further 4.5 parts of ditertiary butoxide were added to 10 parts of the monoethyl ether of ethylene glycol was added and the reaction mixture was added Heated under reflux for 1 hour. The addition was repeated twice, after the first further addition was heated under reflux for one hour. The implementation was then finished. The product had a solids content of 72.8%, a viscosity of 220,000 cp. and an acid number of 72.0.

Example III

920 parts of the butyl ether of ethylene glycol (ButyIcelIosolve) were placed in a reactor and heated to almost boiling point. Ea then became the following mixture of monomers, the 27.2 parts of di-tert-butyl peroxide φΤΒΡ) and 27.2 parts of cumene hydroperoxide, added over the course of 3 hours under reflux cooling:

Weighted parts Butyl acrylate 1496 Styrene 680 Hydroxyethyl methacrylate 136 Methacrylic acid 408

After the addition was complete, three times were 4.5 parts BTBF added in 10 parts of the same butyl ether, whereby

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every Hal after, the first two of these additions 1 hour under Was heated to reflux and 2 hours after the last addition. The implementation was then completed.

The product had a pesticide content of 7.2%, an acid number of 67 and a viscosity of 110,000 cp.

Example IV

An electrically depositable preparation was produced as follows:

There were 253.6 parts of the aoryl resin from Example I and 75 * 6 Parts of ethoxymethoxymethyl melamine (XM-I16) mixed. Then 24.7 parts of diisopropanolamine (melted) were slowly added. After careful mixing, sufficient amounts were obtained of deionized water is added to the solids content to reduce the preparation to 5 »5%. The preparation obtained had a pH of 8.9.

Example V

An electrodeposable preparation was made according to the procedure of Example IV from the following ingredients:

Parts by weight of acrylic resin from Example II 1168 Ethoxymethoxymethyl melamine 216 (ΧΛ-1116)

Diisopropanolamine 121.

This preparation was adjusted to a solids content of 5.5 % by adding ionized water; it had a pH of 8.8.

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Bolapiel VI

£ β became an electric, disposable preparation according to the Procedure of Example IV made from the following ingredients:

Parts by weight Acrylic resin according to Example III 5142 Äthoxymethoxyaet hylme 1 amine (XM-1116) 950 Diisopropanolamine 532.

The plague content of this preparation was determined by the addition of deionized water adjusted to 5 »5%; the preparation had a pH of 8.5

Example VII

An electrodeposable preparation was made according to the procedure of Example IV from the following ingredients:

Parts by weight of acrylic resin of Example I 270.0 Äthoxyaethoxyme thy lme 1 amine 50.6 (XM-1116)

Diisopropanolamine 28.4.

The solids content of the preparation was increased by adding de ionized water adjusted to 5 »5% j the preparation had a pH of 8.9

Example VIII

This «example is about the coating of steel cylinders shown with preparations according to the invention.

The cylinders consisted of an untinned chromium steel (tin-free steel, chromium type) and had welds.

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according to a method on, for example, in the US FS 3 468 4-53.

The items were listed among those shown in the following table Conditions coated so that coatings of similar weight were formed on the individual articles. The measured Results are the volume percent of the film in the seams that contain microbubbles.

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TABLE I.

Electric Resin - Molecular weight Deposit conditions 7.A-1 -h RpflTmnng 250 Film weight percentage Microbubbles • deposited Bath temp. 450 Dimensions "w ^M n 4 " 600 100 Example VI 14 500 5,900 43.3 ° C 4 " 500 74 mg. 70 Example V 94,000 8 600 48.9 ° C 4 ⁿ 76 mg. 10-15 Example VII 71,000 15 100 48.9 ° C 4 " 70 mg. 20-30 ISJ
1–1 Example IV 71,000 15 100 48.9 ° C 82 mg. 3 98 1 cured in a circulating furnace. All coatings became 4 minutes at 196 ° 0 1533

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Other resins of the invention give in a similar manner also improved results.

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Claims (1)

1. A method of electrically depositing a coating on a metal substrate by conducting an electrical current between an electrically conductive metal anode and an electrically conductive cathode in contact with an aqueous dispersion of a polymeric coating composition with the deposition of this coating composition as an adhesive film on the Anode, characterized in that the coating mass (a) about 95 to about 50% by weight, based on the total weight of (a) and (b), of at least part of one neutralized interpolymers from about $ 1 to about $ 2 % By weight of a hydroxyalkyl ester of an alpha, beta-ethylenically unsaturated carboxylic acid, about 1 to about 20 wt .-% of an unsaturated carboxylic acid and at least from another copolymerizable ethylenic unsaturated monomers with an average number molecular weight of at least 6,000 and an average Weight molecular weight of at least 15,000; and (b) about 5 to about 50 weight percent of an amine-aldehyde condensation product contains. 2. The method according to claim 1, characterized in that the condensation product is an etherified melamine-formaldehyde condensation product. 3. The method according to claim 1, characterized in that the Copolymers have an average number molecular weight of at least 7,000 and an average weight molecular weight of at least 50,000. 209812/1533 4-, The method according to claim 3, characterized in that the Paint (a) about 95 to 50% by weight based on the total weight of (a) and (b), an at least partially neutralized copolymer of about 1 to about 20% by weight of a hydroxyalkyl ester an alpha, beta-ethylenically unsaturated carboxylic acid with up to about 6 carbon atoms having from about 2 to about 5 carbon atoms in the hydroxyalkyl radical, from about 1 to about 20% by weight of an unsaturated one Carboxylic acid of up to about 6 carbon atoms and at least one other copolymerizable Contains ethylenically unsaturated monomer; and (b) about 5 to about 50% by weight of an amine-aldehyde condensation product \ f contains. 5. The method according to claim 4-, characterized in that the hydroxyalkyl ester is a hydroxyalky le st it with an acid to 4 carbon atoms, the hydroxyalkyl radical in this ester containing 2 to 3 carbon atoms, and that a melamine-formaldehyde condensation product as the condensation product is used. 6. The method according to claim 5 «characterized in that the Condensation product an etherified melamine-formaldehyde condensation product is. 7. The method according to claim 1, characterized in that the coating mass (a) about 95 to 50% by weight, based on the total weight τοπ (a) and (b), an at least partially neutralized copolymer of about 1 to about 20% by weight of a hydroxyalkyl ester of an alpha, beta-ethylenic 209812/1533 unsaturated carboxylic acid, about 1 to about 20% by weight an unsaturated carboxylic acid and at least one other copolymerizable ethylenically unsaturated monomer with an average number molecular weight of at least 6,000 and an average Weight molecular weight of at least 15,000; and (b) about 5 to about 50% by weight of an amine-aldehyde condensation product, and wherein the time and voltage of the electric current are sufficient that at least one adhesive film 0.0381 mm (1.5 mils) thick is deposited on the anode. 8. The method according to claim 7 »characterized in that the Condensation product is an etherified melamine-formaldehyde condensation product. 9. The method according to claim 7, characterized in that the copolymer has an average number molecular weight of at least 7,000 and an average weight molecular weight of at least 50,000. 10. The method according to claim 9, characterized in that the coating mass (a) about 95 to about 50% by weight, based on the total weight of (a) and (b), of an at least partially neutralized copolymer of about 1 to about 20% by weight of one Hydroxyalkyl ester of an alpha, beta-ethylenically unsaturated Carboxylic acid with up to 6 carbon atoms and with about 2 to 5 carbon atoms in the hydroxyalkyl radical, for example 1 to about 2Jj ~ wt .-% of an unsaturated carboxylic acid with up to about 6 carbon atoms and of at least one other copolymerizable ethylenic unsaturated Monomers, and 209812/1533 (b) about 5 "to about 50 weight percent of an amine-aldehyde condensation Product contains. 11. The method according to claim 10, characterized in that the ester is a hydroxyalkyl ester of an acid having 3 to 4 carbon atoms This ester contains 2 to 3 carbon atoms in the hydroxyalkyl radical, and that a melamine-formaldehyde condensation product is used as the condensation product will. 12. The method according to claim 11, characterized in that the melamine-formaldehyde condensation product is etherified. 13. The method according to claim 1, characterized in that the paint (a) about 95 to 50% by weight, based on the total weight of (a) and (b), of an at least partially neutralized copolymer of about 1 to about 20 % by weight of a hydroxyalkyl ester of an alpha, beta-ethylenically unsaturated carboxylic acid , about 1 to about 20 wt .-% of an unsaturated carboxylic acid and at least one other copolymerizable ethylenically unsaturated monomers having an average number molecular weight of at least 6000 and an average weight molecular weight of 15 000; and (b) about 5 to about 50 weight percent of an amine-aldehyde condensation product the time and voltage sufficient to form an adherent film on the anode of a thickness of at least about 0.0381 mm (1.5 mils) and thereafter applying the coating for a period of less than is cured for about 5 minutes at a temperature above about 149 ° C. 209812/1533 21U135 Process according to Claim 13, characterized in that the condensation product is an etherified melamine-formaldehyde condensation product. 15 · The method according to claim 13, characterized in that the Copolymers have an average number molecular weight of at least 7,000 and an average weight molecular weight of at least 50,000. 16. The method according to claim 15, characterized in that the Paint (a) about 95 to about 50% by weight, based on the total weight of (a) and (b), of an at least partially neutralized copolymer of about 1 to about 20% by weight of a hydroxyalkyl ester of an alpha, beta-ethylenic unsaturated carboxylic acid having up to about 6 carbon atoms and having about 2 to about 5 carbon atoms in the hydroalkyl radical, about 1 to about 20% by weight of one unsaturated carbonates having up to about 6 carbon atoms and of at least one other copolymerizable ethylenically unsaturated monomer; and (b) about 5 to about 50 '. iw .-% of an amine-aldehyde condensation product 9 contains. 17. The method according to claim 16, characterized in that the dafi Ester is a hydroxyalkyl ester of 3 to 4 carbon atoms, this ester having 2 to 3 carbon atoms contains in the hydroxyalkyl radical, and that a melamine-formaldehyde condensation product is used as the condensation product. 18 *. Method according to claim 17, characterized in that the Condensation product is an etherified melamine-formaldehyde condensation product. 209812/1533 2-U4135 19. Electrically depositable polymeric coating composition in aqueous dispersion, characterized in that it (a) about 95 to about 50% by weight, based on the total weight of (a) and (b), of an at least partially neutralized copolymer of about 1 to about 20 % by weight of a hydroxyalkyl ester of an alpha, beta-ethylenically unsaturated Carboxylic acid, about 1 to about 20 % of an unsaturated carboxylic acid and at least one other mixed-polymerizable, ethylenically unsaturated monomer with an average number molecular weight of at least 6,000 and an average weight molecular weight of at least 15,000; and (b) about 5 to about 50 weight percent of an amine-aldehyde condensation product contains. 20. Coating composition according to claim 19 *, characterized in that the condensation product is an etherified melamine-formaldehyde condensation product is. 21. Coating composition according to claim 19, characterized in that the mixed polymer has an average number molecular weight of at least 7,000 and a weight average molecular weight of 50,000. 22. Coating composition according to claim 21, characterized in that it (a) about 95 to about 50% by weight, based on the total weight of (a) and (b), of a partially neutralized copolymer of about 1 to about 20% by weight of a hydroxyalkyl ester of an alpha, beta-ethylenically unsaturated carboxylic acid ydroxyalkylrest with up to about 6 carbon atoms and having from about 2 to about 5 carbon atoms in ^R, about 1 to about 20 wt .-% of a xxt \ f - * ettigten carboxylic acid having up to about 6 carbon 209812/1533 "**". 21U135 atoms and at least one other copolymerizable ethylenically unsaturated monomers; and (b) from about 5 to about 50 weight percent of an amine-aldehyde condensation product contains. 23. ÜberzugβΒ & Βββ according to claim 22, characterized in that the hydroxyalkyl ester of the esters of an acid with 3 to 4 Carbon atoms, this ester being 2 to 3 carbon atoms in the hydroxyalkyl radical 'contains, and that as Condensation product a melaain-formaldehyde condensation product is used. Coating composition according to Claim 23, characterized in that the condensation product is an etherified melamine-formaldehyde condensation product is 209812/1533