EP0287571A1

EP0287571A1 - Anionically-precipitable binder, process for its production, coating based thereon and use thereof

Info

Publication number: EP0287571A1
Application number: EP87901264A
Authority: EP
Inventors: Hans-Dieter Hille; Hans-Jörg HÖLSCHER; Uwe Reichelt; Karl-Heinz Scherping
Original assignee: BASF Lacke und Farben AG
Current assignee: BASF Farben und Fasern AG
Priority date: 1985-12-21
Filing date: 1986-12-10
Publication date: 1988-10-26
Also published as: EP0227995B1; ES2024415B3; WO1987003894A1; ATE65535T1; DE3680497D1; DE3545617A1; EP0227995A3; EP0227995A2; BR8607233A

Abstract

An anionically-precipitable binder (A), water-dispersable by neutralizing with bases, which binder can be obtained by reaction of epoxy resins with an average molecular weight of at least 3 000 g/mol, based on biphenols with polyester polycarboxylic acids the functionality of which ranges from 3 to 8 and whose average molecular weight is smaller than 2 000 g/mol. The binder (A) has an acid number of between 50 and 120. In addition, process for producing the anionically precipitable binder (A) as well as coating based on the binder (A), for anodic electrophoretic coating and for use in spray-painting of tins.

Description

INTERNATIONAL APPLICATION PUBLISHED AFTER THE INTERNATIONAL COOPERATION AGREEMENT IN THE PATENT AREA (PCT)

(51) International Patent Classification 4: (11) International publication number: WO 87/038 C09D 5/44, C08L 63/00, 67/00 AI (43) Internationales

Release date: July 2, 1987 (Jul 2, 1987

(21) International file number: PCT / EP86 / 00734 (74) Common representative: BASF LACKE + FARBE AG; Postfach 61 23, T 4400 Münster (DE).

(22) International filing date:

December 10, 1986 (December 10, 1986)

(81) Destination countries: AT (European patent), BE (European patent), BR, CH (European sponsor

(31) Priority reference number: P 35 45 617.5 DE (European patent), FR (European sponsor GB (European patent), IT (European sponsor

(32) Priority date: December 21, 1985 (December 21, 1985) LU (European patent), NL (European sponsor SE (European patent), US.

(33) Country of priority: DE

(71) Applicant (for all destinations except US): Published

BASF LACKE + FARBEN AKTIENGESELL with international research report. SHAFT [DE / DE]; Max-Winkelmann-Strasse 80, D-4400 Münster (DE).

(72) inventor; and

(75) Inventor / applicant (only for US): HILLE, Hans-Dieter [DE / DE]; In the Schlade 24, D-5060 Bergisch Gladbach (DE). HÖLSCHER, Hans-Jörg [DE / DE]; Haus Angelmodde 28, D-4400 Münster (DE). REICHELT, Uwe [DE / DE]; Tulpenweg 15, D-4542 Tecklenburg-Ledde (DE). SCHERPING, Karl-Heinz [DE / DE]; Am Klosterwald 34, D-4400 Münster (DE).

(54) Title: ANIONICALLY-PRECIPITABLE BINDER, PROCESS FOR ITS PRODUCTION, COATING BASE THEREON AND USE THEREOF

(54) Name: ANIONICALLY DEPOSIBLE BINDING AGENT, METHOD FOR THE PRODUCTION OF THE COATING AGENT BASED ON THE BINDING AGENT AND THE USE THEREOF

(57) Abstract

An anionically-precipitable binder (A), water-dispersable by neutralizing with bases, which binder can be obtain by reaction of epoxy resins with an average molecular weight of at least 3,000 g / mol, based on biphenols with polyest polycarboxylic acids the functionality of which ranges from 3 to 8 and whose average molecular weight is smaller than 000 g / mol. The binder (A) has an acid number of between 50 and 120. In addition, process for producing the anionical precipitable binder (A) as well as coating based on the binder (A), for anodic electrophoretic coating and for use in spra painting of tins.

(57) Summary

Anionically separable binder (A) which is water-dispersible by neutralization with bases, obtainable by reaction of epoxy resins with an average molecular weight of at least 3000 g / mol based on B phenols with polyester polycarboxylic acids, the functionality of which is 3 to 8 and the average molecular weight is less than Is 2000 g / mol. The binder (A) has an acid number of 50 to 120. The invention also relates to processes for the preparation of the anionically separable binders (A), furthermore coating compositions based on the binder (and, the use of the coating compositions based on the binder (A) for anodic electrocoating as well as for use for spray painting cans.

ONLY FOR INFORMAΩON

Code used to identify PCT contracting states on the headers of the international writings

Publish registrations according to the PCT.

AT Austria FR France MR Mauritania

AK Australia GA Gabon MW Malawi

BB Barbados GB United Kingdom NL Netherlands

BE Belgium HU Hungary NO Norway

BG Bulgaria rr Italy RO Romania

B Benin JP Japan SD Sudan

BK. Brazil KP Democratic People's Republic of Korea SE Sweden

CF 'Central African Republic KR Republic of Korea SN Senegal cσ Congo LI Liechtenstein SU Soviet Union

CH Switzerland LK Sri Lanka TD Chad

CM Cameroon LU Luxembourg TG Togo oε Germany, Federal Republic of MC Monaco US United States

DE Denmark MG Madagascar

FI Finland ML Mali

Anionically separable binder, process for its

Production, coating agents based on the binder and their use.

The invention relates to an anionically separable binder (A) which is water-dispersible by neutralization with bases and which is obtainable by reacting epoxy resins with an average molecular weight of at least 3000 g / mol on the basis of bisphenols with a carboxyl carrier.

Epoxy resins, for example based on 2,2-bis (4-hydroxyphenyl) propane, ie bisphenol A, are known as binders for lacquers suitable for coating cans, both on the basis of organic solvents and on a water basis.

With conventional spray application, low

Solids are worked to set the required low viscosity. This results in a heavy burden from solvent emissions.

The advantages of aqueous systems are a significantly lower solvent emission and a cost reduction due to the saved solvents.

However, the application of synthetic resin dispersions by means of electrocoating is particularly advantageous, with an almost 100% paint yield and a further reduced emission compared to spray application. In addition, the coating of a wide variety of can geometries is possible due to the effect of wrap-around in the electrocoating process. For beverage cans with predominantly acidic filling materials, the anodic electrocoating is more advantageous than the cathodic variant, since the films deposited cathodically mostly contain amine groups and can therefore be dissolved by acidic filling materials.

To use binder systems in the aqueous medium, these must be modified by introducing solubilizing groups in such a way that a water-soluble or water-dispersible system is formed.

From P.V. Robinson, J. Coat. Technol. 53, No. 674, page 23 (1981) and CG. Demmer and N.S. Moss, J. Oil Col. Chem. Assoc. 65, 249 (1982), water-dilutable binder systems based on epoxy resin for can coatings are known. Carboxyl groups are incorporated into the epoxy resin, for example by reaction of the epoxy groups with di- or polycarboxylic acids. Another way of introducing carboxyl groups into the binder is to react a binder containing hydroxyl groups with a carboxylic anhydride. The water solubility of these binders is achieved by neutralization with volatile amines. Systems in which polycarboxylic acids have half ester functions

Polymers are bound, however, are very susceptible to hydrolysis. The resulting aqueous dispersions therefore have an insufficient storage stability.

From DE-PS 27 47 818 are anionically separable, water-dispersible by neutralization with bases

Known binders which are obtained by reacting epoxy resins with an average molecular weight of at least 3000 g / mol based on bisphenols with a carboxyl carrier. The water-solubilizable

Resin is made by adding a bisphenol to the diglycidyl ether of a bisphenol, the bisphenol diglycidyl ethers having epoxide equivalent weights up to about 2500. The adduct obtained is further implemented according to DE-PS 27 47 818 with carboxylic acid anhydrides, such as, for example, with trimellitic anhydride, and crosslinked with aminoplast resins. The resulting aqueous coating compositions are preferably used according to the patent for coating metal packaging containers. The disadvantage of the compositions known from DE-PS 27 47 818 is that the carboxylic acids are bound to the polymeric epoxy base resin via half-ester functions, which results in susceptibility to hydrolysis.

The invention was therefore based on the object of developing modified epoxy resins, in particular for coating cans and beverage cans, the modified epoxy resins being intended to give storage-stable, aqueous dispersions. Coating agents produced from this should process flawlessly using conventional coating techniques and in particular should be able to be applied without problems using the anodic electrocoating process. The electrodeposition paints should allow for coating times between 0.5 and 30 seconds, taking into account the conditions of industrial can production. Under these conditions, the film thicknesses of 4 - 10 μm typical for sheet metal packaging should be able to be produced. The deposited films should be insensitive to the flushing media in question. In addition, the electrodeposition paints should be able to be used to the same extent for different metal substrates, such as tinplate and aluminum. The baked paint films should at least achieve or exceed the level of properties of conventional interior protective paints with regard to freedom from pores, filling material resistance, sheet adhesion, hardness, elasticity and taste neutrality. For the first assessment of the resistance to contents in the form of short tests, it is important that the resistance to gasurization or sterilization of baked paint films compared to different test solutions, in the simplest

Case against water.

Surprisingly, it was found that the object is achieved by a binder of the type mentioned at the outset, which is characterized in that the carboxyl carrier is a polyester polycarboxylic acid whose functionality is 3 to 8 and whose average molecular weight is less than 2000 g / mol, and the binder (A) has an acid number of 50 to 120.

The epoxy resins based on bisphenols are preferably reaction products of bisphenol A or bisphenol F with epichlorohydrin. According to the invention, these epoxy resins must have an average molecular weight of at least 3000 g / mol.

Known polycondensates of aromatic and / or aliphatic dicarboxylic acids, aromatic dicarboxylic acid anhydrides, aromatic tricarboxylic acid anhydrides, aromatic tetracarboxylic acid anhydrides and dianhydrides as well as aliphatic and cycloaliphatic diols and triols are suitable as polyester polycarboxylic acids. It is particularly advantageous if the functionality of the polyester carboxylic acids is 4 to 6. The polycondensates can also be modified with ester diols and / or glycide esters of monocarboxylic acids. Hydroxypivalic acid neopentylglycol esters may be mentioned as an example of suitable ester diols.

Polycondensates of at least trihydric polycarboxylic acids or at least trihydric polycarboxylic anhydrides with diols are particularly preferably used. An example of this is the condensation product of trimellitic anhydride and 2,2-dimethyl-1,3-propanediol, that is to say neopentyl glycol. The production of the poly Ester polycarboxylic acids are carried out according to the conditions known to those skilled in the art for polyester esterification reactions.

Surprisingly, it has been found that reaction products of epoxy resins with polyester polycarboxylic acids with a proportion of anhydride groups which cannot be ruled out lead to hydrolysis-stable, aqueous dispersions.

According to the invention, the carboxyl group-containing binder (A) has an acid number of 50 to 120, it being preferred if the acid number of the binder (A) is 70 to 90.

The invention also relates to a process for the preparation of an anionically separable binder (A) which is water-dispersible by neutralization with bases by reaction of epoxy resins having an average molecular weight of at least 3000 g / mol and based on bisphenols with a carboxyl carrier in an organic solvent or solvent mixture , which is characterized in that the carboxyl carrier is a polyester polycarboxylic acid, the functionality of which is 3 to 8 and whose average molecular weight is less than 2000 g / mol, and the binder (A) has an acid number of 50 to 120.

The functionality of the polyester polycarboxylic acid is preferably 4 to 6. It is particularly advantageous if the polyester polycarboxylic acids are reaction products of an at least trivalent polycarboxylic acid or an at least trivalent polycarboxylic anhydride with a diol. The condensation product of trimellitic anhydride and 2,2-dimethyl-1,3-propanediol should be mentioned here. The polyester polycarboxylic acids can be modified with ester diols and / or glycide esters of monocarboxylic acids.

The acid number of the binder (A) is advantageously 70 to 90.

The high molecular weight epoxy resins are reacted with polyester polycarboxylic acids in a suitable solvent or solvent mixture. The reaction temperature is 20 to 220 ° C, the temperature range of 80 to 150 ° C is preferred. Advantageously, catalysts such as e.g. tertiary amines used. A particularly suitable catalyst is N, N-dimethylbenzylamine.

The invention also relates to an anionic deposit which is water-dispersible by neutralization with bases

Electrocoating material based on the epoxy resin binder according to the invention described above

(A), the coating agent containing organic solvent and water, and optionally up to 16% by weight of crosslinking agent (B), based on the sum of (A) and (B), and optionally pigments, fillers, paint auxiliaries and catalysts. The binder (A) can be prepared by the process according to the invention described above.

Amino resins and / or phenolic resins are preferably used as crosslinking agents (B). The electrodeposition coating compositions according to the invention furthermore contain an organic solvent or a mixture of organic solvents which positively influence the effectiveness of the anodic deposition and the course of the paint film. Monoalcohols with 4 to 18 carbon atoms, glycol ethers, such as, for example, ethylene glycol monoethyl ether and its higher homologues with 5 to 20 carbon atoms, or corresponding ethers of 1,2- and 1,3-propanediol are suitable. The content of cosolvents in the aqueous dispersion, based on the total weight of the coating composition, is generally from 1 to 15% by weight, preferably from 4 to 12% by weight.

The electrodeposition coating compositions according to the invention optionally contain pigments, fillers and coating auxiliaries. The latter are plasticizers,

Stabilizers, wetting agents and dispersants to name.

If necessary, catalysts are also used.

The present invention also relates to a process for the preparation of the above-described, anionically separable electrodeposition coating composition which is water-dispersible by neutralization with bases, which is characterized in that the binder (A) is precondensed in organic solvent with the crosslinking agent (B) and the binder system obtained is submerged Addition of bases is dispersed in water and optionally pigments, catalysts, fillers and paint auxiliaries are added, with the

Dispersion in water a solids content of 5 to

40% by weight is set.

The invention further relates to a process for the preparation of the electrocoating material described, which is characterized in that the binder (A) according to the invention with the crosslinking agent

(B) is mixed in organic solvent that

Mixture is dispersed in water with the addition of bases and optionally pigments, catalysts, filler

Production of a polyester polycarboxylic acid (1)

20.6 parts of 4-methyl-2-pentanone are weighed into a four-necked flask equipped with a stirrer, thermometer and water separator and heated to 110.degree. 35.6 parts of trimellitic anhydride are added with stirring. After adding 12.9 parts of U, 2 dimethyl-1, 3-propanediol in portions, the mixture is heated from 110 C to 200 C within 5 hours. The water released during the condensation is separated off via the water separator. When the acid number has dropped to 300 mg KOH / g, the 4-methyl-2-pentanone is distilled off in vacuo and the temperature is reduced to 140.degree. The addition of 31.0 parts of ethylene glycol monobutyl ether results in a 60% solution which has 40% strength in ethylene glycol monobutyl ether and has a viscosity of 300 mPa.s (23 C).

Example 1: Modification of an epoxy resin with the polyester polycarboxylic acid (1)

In a four-necked flask equipped with a stirrer, thermometer and reflux condenser, 31.1 parts of the polyester polycarboxylic acid (1) are mixed with 25.0 parts of ethyl

After cooling to 90 ° C., 6.3 parts of a phenol formaldehyde resin (resol type based on bisphenol A) are added and the mixture is stirred at 90 ° C. for 2 hours. After cooling to 60 ° C., 6.3 parts of triethylamine are added and the solid is adjusted to 55% with ethylene glycol monobutyl ether.

Comparative Example 1: Modification of an epoxy resin with trimellitic anhydride

To produce a comparative batch, the high molecular weight epoxy resin used in Example 1 is reacted with trimellitic anhydride with a monocarboxylic acid after esterification of the glycidyl residues.

For this purpose, 41.8 parts of a high molecular weight epoxy resin based on bisphenol A with an epoxy equivalent weight of 3300 are dissolved in 41.0 parts of ethylene glycol monobutyl ether and reacted at 130 ° C. with 1.94 parts of isononanoic acid and 0.06 part of N, N-dimethylbenzylamine until the acid number has dropped below 3 mg KOH / g. 7.7 parts of trimmelitic anhydride are added and the temperature is maintained until an acid number of 80 mg KOH / g is reached. After cooling to 90 ° C., 3.5 parts of a phenol formaldehyde resin (resol type based on bisphenol A) are added and the mixture is stirred at 90 ° C. for 2 hours. After cooling to 50 ° C 4.0

Parts of triethylamine added. The solid body is then 55%.

Comparative Example 2: Modification of an epoxy resin with tetrahydrophthalic anhydride

To create a further comparison link, this is high molecular weight epoxy resin used in Example 1 after esterification of the glycidyl residues with a monocarboxylic acid with tetrahydrophthalic anhydride.

The procedure is as described in Comparative Example 1, except that the 7.7 parts of trimellitic anhydride are replaced by 11.6 parts of tetrahydrophthalic anhydride and condensation is carried out to an acid number of 73 mg KOH / g.

Preparation of binder dispersions from the binders of Example 1 and Comparative Examples 1 and 2

The binder solutions of Example 1 and Comparative Examples 1 and 2 are each slowly dispersed into deionized water with vigorous stirring and adjusted to a solids content of 25%. The properties and characteristics of the resulting dispersions are summarized in Table 1.

Table 1

Dispersion A B C Binder Example 1 Comparative Example 1 Comparative Example 2

Storage stability of the

Dispersion> 6 mon (20 ° C) <1 mon (20 ° C) <1 mon (20 ° C) pH 7.8 8.5 5.9 spec. conductivity

(µS / cm) 2500 2000 2200 The binder dispersions B and C do not have sufficient storage stability at room temperature. After a month, the binder is largely coagulated and the dispersion is destroyed. Dispersion A, on the other hand, is free of sediment even after 6 months of storage at room temperature.

Example 2: Coating a beverage can with the binder dispersion A from Table 1

The anionic binder dispersion is diluted to a solids content of 12.5% with deionized water. An unpainted, two-part beverage can made of tinplate is held at the edge of the flange with an electrically conductive clamp, filled with the electro-dip lacquer and completely immersed in a conductive container with a diameter of 20 cm that is insulated against earth, which has also previously been filled with the electro-dip lacquer. The positive pole of a DC voltage source is connected to the socket and the negative pole to the outer vessel. The coating is done using an auxiliary cathode inside the can. After rinsing with deionized water, bake in a forced air oven at 210 ° C for 2 minutes. The can is completely covered on the inside and outside with a thin clear lacquer film that is pore-tight. Measured values cf. Table 2.

Example 3: Coating a beverage can with the pigmented binder dispersion A from Table 1

The binder from Example 1 is pigmented with titanium dioxide (binder: pigment = 1: 1) and diluted to 12.5% solids with deionized water. The coating is carried out analogously to Example 2. The can is completely covered with a white lacquer film.

Measured values cf. Table 2.

Comparative Example 3: Coating a beverage can with the binder dispersion B

The anionic binder dispersion B is diluted to a solids content of 12.5% with deionized water. The coating is carried out analogously to Example 2. The can is coated on the inside and outside with a matt clear lacquer film which is not pore-tight and has surface defects. Measured values cf. Table 2.

Comparative Example 4: Coating a beverage can with the binder dispersion C

The anionic binder dispersion C is diluted to a solids content of 12.5% with deionized water. The coating is carried out analogously to Example 2. The inside and outside of the can is coated with a matt clear lacquer film which is not pore-tight and has surface defects. Measured values cf. Table 2.

Table 2

Example 2 Example 3 Comparative Comparative Example 3 Example 4

Solids 12.5 12.5% 12.5% 12.5% pH 7.8 7.8 8.5 5.9 spec. Guide 2500 μS / cm 2600 μS / cm 2000 μS / cm 2200 μS / cm

Bath temperature 27 ° C 27 ° C 27 ° C 27 ° C

Separation time 20 s 20 s 20 s 20 s

Separation voltage 50 V 60 V 160 V 90 V paint / can 480 mg 750 mg 450 mg 460 mg

Surface glossy glossy matt matt

Porosity mA (enamel rater) 0.0 0.0 10 10

Varnish (cross cut) Gt 0 Gt 0 Gt 1 Gt 1

Sterilization with water (30min / 121 ° C) i. 0. i. Blushing (Blushing)

The deposited and baked lacquer films show in all examples no odor, taste or color impairments compared to water as a filling. Similar results are obtained if, instead of a 2-part tin made of tinplate, one made of aluminum is used. Example 4: Coating a beverage can by means of

Spray painting with binder dispersion A

With the anionic binder dispersion A

Spray-painted inside of a 2-piece beverage can made of tinplate. 65 bar is selected as the spray pressure. The paint is baked in a forced air oven at 210 ºC for 2 minutes. The result is an applied layer of lacquer of 220 mg dry / 0.33 1-can. The paint film is clear and shiny and has a porosity (enamel rater) of 0.8 mA. The other paint properties (adhesion and resistance to sterilization) correspond to those of Examples 2 and 3 from Table 2.

Claims

1. Anionically depositable, by neutralization with bases water-dispersible binder (A), obtainable by reaction of epoxy resins with an average molecular weight of at least 3000 g / mol based on bisphenols with a carboxyl carrier, characterized in that the carboxyl carrier is a polyester polycarboxylic acid, the Functionality is 3 to 8 and its average molecular weight is less than 2000 g / mol, and the binder (A) has an acid number of 50 to 120.

2. Binder according to claim 1, characterized in that the functionality of the polyester polycarboxylic acids is 4 to 5.

3. Binder according to claim 1 or 2, characterized in that the polyester polycarboxylic acids are reaction products of an at least trivalent polycarboxylic acid or an at least trivalent polycarboxylic anhydride with a diol.

4. Binder according to claim 3, characterized in that the polyester polycarboxylic acids are condensation products of trimellitic anhydride and 2,2-dimethyl-1,3-propanediol.

5. Binder according to claim 1, 2, 3 or 4, characterized in that the polyester polycarboxylic acids are modified with ester diols and / or glycidyl esters of monocarboxylic acids.

6. Binder according to claim 1, 2, 3, 4 or 5, characterized in that the acid number of the binder (A) is 70 to 90.

7. A process for the preparation of an anionically separable binder (A) which is water-dispersible by neutralization with 3ases by reaction of epoxy resins with an average molecular weight of at least 3000 g / mol based on bisphenols with a carboxyl carrier in an organic solvent or solvent mixture, characterized in that that the carboxyl carrier is a polyester polycarboxylic acid, the functionality of which is 3 to 3 and the average molecular weight is less than 2000 g / mol, and the binder (A) has an acid number of 50-120.

8. The method according to claim 7, characterized in that the functionality of the polyester polycarboxylic acids is 4 to 6.

9. The method according to claim 7 or 8, characterized in that the polyester polycarboxylic acids are reaction products of an at least trivalent polycarboxylic acid or an at least trivalent polycarboxylic acid anhydride with a diol.

10. The method according to claim 9, characterized in that the polyester polycarboxylic acids are condensation products of trimellitic anhydride and 2,2-dimethyl-1,3-propanediol.

11. The method according to claim 7, 8, 9 or 10, characterized in that the polyester polycarboxylic acids with ester diols and / or glycide esters from Monocar bonic acids are modified.

12. The method according to claim 7, 8, 9, 10 or 11, characterized in that the acid number of the binder (A) is 70 to 90.

13. The method according to claim 7, 8, 9, 10, 11 or 12, characterized in that the implementation of the

Epoxy resin with the polyester polycarboxylic acids at 80 to 150 ° C, optionally using a catalyst, is carried out

14. Anionically depositable, by neutralization with 3ases water-dispersible electrocoat based on the binder (A), prepared according to claim 7, 8, 9, 10, 11, 12 or 13, wherein the coating agent organic solvent and water and optionally up to 16 wt .-% crosslinking agent (3), based on the sum of (A) and (B), and optionally contains pigments, fillers, paint auxiliaries and catalysts.

15. electrocoating material according to claim 14, characterized in that the crosslinking agent (B) are aminoplast resins and / or phenolic resins.

16. Electrodeposition coating composition according to claim 14 or 15, characterized in that it contains 1 to 15% by weight, preferably 4 to 12% by weight, based on the total weight of the coating composition, organic or organic solvents.

17. Process for the preparation of the electrodeposition coating composition according to An, which can be separated off by anionic deposition and water-dispersible with bases Say 14, 15 or 16, characterized in that the binder (A) with the crosslinking agent (B) is precondensed in organic solvent and the binder system obtained is dispersed in water with the addition of bases and, if appropriate, pigments, catalysts, fillers and paint auxiliaries are added , with a solids content of 5 to 40% by weight being set when dispersed in water.

13. A process for the preparation of the anionically depositable electrodeposition coating composition which is water-dispersible by neutralization with 3ases according to Claim 14, 15 or 16, characterized in that the binder (A) is mixed with the crosslinking agent (B) in organic solvent, the mixture with the addition of bases is dispersed in water and, if appropriate, pigments, catalysts, fillers and paint auxiliaries are added, a solids content of 5 to 40% by weight being set when dispersed in water.

19. A process for the preparation of the anionically depositable electrodeposition coating composition which is water-dispersible by neutralization with bases as claimed in claim 14, 15 or 16, characterized in that the binder (A) is dispersed in water in organic solvent with the addition of bases and, if appropriate, pigments, catalysts, fillers and paint auxiliaries are added, a solids content of 5 to 40% by weight being set for the dispersion in water.

20. A method for coating an electrically conductive substrate, in which the substrate is immersed in an aqueous bath based on the coating agent, prepared according to claim 17, 18 or 19, the substrate is switched as an anode, a film is deposited on the substrate by means of direct current the substrate is removed from the 3ad and the film is cured by baking.

21. Use of the anionically depositable electrodeposition coating composition, prepared by the process according to claim 17, 18 or 19, for the anodic electrodeposition coating of cans.

22. Use of the coating agent, produced by the method according to claim 17, 18 or 19, for the Soritz painting of cans.