DE2411349A1 - PROCESS FOR THE MANUFACTURING OF HEAT-CURABLE, WATER-DILUTABLE SYNTHETIC RESINS SUITABLE FOR THE ELECTRO-DIPPING PROCESS - Google Patents

Description

Process for the production of thermosetting , water-thinnable synthetic resins suitable for the electro-immersion process.

The present invention relates to a process for the preparation of thermosetting materials for the electrodeposition process suitable, water-thinnable synthetic resins based on of reaction products of maleic anhydride with mixtures of polybutadiene, unsaturated hydrocarbon resins and unsaturated fatty acid glyceride esters, characterized in that a mixture consisting of:

a) 35 - 60 wt -.% of a polybutadiene having an average molecular weight of 750 - 2000 and an iodine number of between 300 - 450

b) 10-30 wt -.% of a reactive, predominantly aliphatic or cycloaliphatic constructed hydrocarbon resin with a viscosity between 30 -) measured 800 cP (at 70 # strength solution in toluene at 20 ⁰ C, an iodine value of I60 - 220 (after ASTM D 555), an average molecular weight of approx. 400 - 700, consisting of

b ^) 5-30 wt. % polyisoprene,

b ~) 30 - 80 wt -.% cyclopentadiene and / or dicyclopentadiene and / or alkyl or alkylene derivatives of cyclopentadiene,

b) 5-15 weight -% of other mono- or polyunsaturated hydrocarbons having 5 - s which are composed predominantly aliphatic or cycloaliphatic 12 carbon atoms.

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c) 5 ~ 25 wt .- ^ of a fatty acid glyceride ester, the Fatty acid residue contains 16-18 C atoms and the fatty acid glyceride ester has an iodine number between 1 * 10-220, prepolymerized by heating to 200-270 ° C is until the reaction mixture of components a, b and c, which has an initial viscosity of about 100-350 see (measured according to DIN 53211), has viscosities between 500-2000 see (measured according to DIN 53211), then the mixture obtained with

d) 15 - 20 wt -.% maleic anhydride at 18O-19O ° C is reacted until no free maleic anhydride is present more and

e) the anhydride groups present in the adduct obtained by hydrolysis with water or by alcoholysis with the amount required for the formation of half-esters monohydric alcohols with 1-4 carbon atoms are opened.

In German Offenlegungsschrift No. 2,016,223 the preparation of water-dilutable polymeric products is described that an unsaturated Fettsäureesters, 85-10 wt .- $ of 10-70 wt -.% Polybutadiene and 5-20 weight -% of maleic anhydride exist..

On page H, last section of this laid-open specification, it is stated that the production takes place in such a way that first the unsaturated fatty acid ester and the polybutadiene are reacted with one another at 180-270 ° C. and then the adduction of the maleic anhydride takes place. The binders obtained in this way are intended to provide electrophoretically deposited films which, after stoving, have better corrosion protection, better permanent elasticity and good hardness. The bathroom solutions should be excellent

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Have storage stability and the binder should be able to be deposited without problems even at high voltages. However, the binders obtained according to this information have a number of disadvantages. So they own with Electrophoresis baths made with these binders only have insufficient throw-around values, the films harden on stoving, especially with thicker layers (over 24 y), only insufficiently through, and the electrodeposited films show after spraying with water and thereafter Branding water drop marks.

These disadvantages are overcome by the synthetic resins produced by the process according to the invention. the Synthetic resins obtained by this process have good properties when used as binders in electrodeposition baths to excellent throwing power. The electrodeposited films harden on baking at about 180 ° C for 30 minutes also in thick layers (23 - 28 μ) well done. The electrodeposited films can be sprayed with water, and the films show no water droplet markings after baking.

In British Patent 1,102,652 the manufacture more water-soluble, for the electric red calibration process suitable binder described, wherein polybutadiene is reacted with maleic anhydride. This with these However, electrophoresis baths made with binders have inadequate throwing power. The films show Insufficient hardness after baking.

In British Patent Specification 1,154,17 ¹ I is the preparation of water-dilutable, described for the electrodeposition method suitable binder, which consists of 40 - 80 wt .- - polybutadiene, 15 - 55 parts by weight unsaturated fatty acid and S 5-15 wt -.% Consist of fumaric acid. On page 2, lines 38 - 43 of this patent specification it is mentioned

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that hydrocarbon resins based on cyclopentadiene or piperylene can also be added. These too Binders show poor throwing power in electrophoresis baths. The films obtained show after spraying with water and stoving water drop markings and the films have insufficient curing.

In the process of the present invention, polybutadienes as homopolymers of butadiene can be used as component a with an average molecular weight of 750-2000 and iodine numbers between 300-450 can be used.

Polybutadienes are to be understood as meaning all commercially available isomers, both those with central ice and trans double bonds, as well as those with vinyl double bonds. Particularly preferred is:

1.) a polybutadiene with an average molecular weight of approx. 1400, an iodine number of 450, the double bonds being 65-75% 1,4-cis-, 25-35% 1,4-trans- and less than 1% 1, Have 2-vinyl configuration.

2.) A polybutadiene with an average molecular weight of 10000-1500, an iodine number of 420, the double bonds being 10 $ 1,4-cis, 45 % 1,4-trans and 45% 1,2-vinyl -Configuration.

3.) A polybutadiene with an average molecular weight of 900, an iodine number of 360, with the double bonds to 10 $ 1,4-cis-, to 45 $ 1,4-trans- and zu 45% have 1,2-vinyl configuration.

Likewise, butadiene polymers with terminal carboxyl or hydroxyl groups are to be understood here, however, these do not belong to the preferred execution

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form. The preparation of these butadiene polymers with terminal carboxyl or hydroxyl groups is described in "Rubber and Plastics Age" 196 ¹ I, Volume 45, No. 11, page 13 ¹ U.

As component b, unsaturated hydrocarbon resins with a predominantly aliphatic or cycloaliphatic structure are more suitable, which are obtained by polymerizing unsaturated Cj cuts obtained during petroleum distillation. These carbon-hydrogen resins should have iodine numbers between βΟ - 220 and viscosities between 30 - 800 cP ( ^{measured in 70 # solution in toluene at 20 °} C.). The suitable for the inventive method Kohlenwasserstoffharz'e are based on 5-30 wt -.% Polyisoprene, J50 - 80 wt ..% ~ cyclopentadiene or dicyclopentadiene and / or alkyl or alkylene derivatives of cyclopentadienes and 5-15 wt .- ^ other mono- or polyunsaturated hydrocarbons with 5 to 12 carbon atoms. be constructed.

Triglycerides are the unsaturated fatty acid glyceride esters unsaturated fatty acids, such as tall oil fatty acid, soybean oil fatty acid, linseed oil fatty acid, ricinic fatty acid, wood oil fatty acid, Peanut fatty acid, rapeseed oil fatty acid and the like.

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Suitable individually or as a mixture, wood oil and ricin oil are preferred. In the preferred embodiment, Linseed oil is used as an unsaturated fatty acid glyceride ester.

The polybutadiene (a), the hydrocarbon resin (b) and the fatty acid glyceride ester (c) is first heated to 200 to 270 ° C. under protective gas. As a protective gas is Suitable for nitrogen or carbon dioxide. The heating is continued until the Viscosity from 100 - 3OO seconds. to 430 - 2000 sec. (DIN 53211) has increased. Viscosity values higher than those specified should be avoided, since then the accumulation of Maleic anhydride is no longer possible without the risk of gelation or the films electrophoretically applied with such products do not have sufficient flow. If the viscosity values of the intermediate product are too low, the throwing power values of the end product are in general insufficient, and the films are very sensitive to water droplets. The starting viscosities of the mixture of components (a) - (c) are between 100 and 300 seconds. (DIN 532II). After reaching the desired final viscosity the polymerized mixture is reacted with maleic anhydride. This reaction takes place at 180-190 ° C, whereby care must be taken to ensure that the temperature range will not leave.

At lower temperatures the addition does not proceed quickly enough, at higher temperatures there is a risk the gelling of the approaches.

Polymerization inhibitors are preferably added to the reaction mixture, e.g. hydroquinone, tert-amy! Hydroquinone, Diphenylamine, diphenylenedianine, copper or copper salts, e.g. copper naphthenate. The reaction continues for so long up to the level of free maleic anhydride

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Ö% has fallen. This generally takes 3-8 hours. The anhydride group in the reaction product (adduct) is then opened either by treatment with water (hydrolysis), optionally under excess pressure, or by treatment with monohydric saturated aliphatic alcohols (alcoholysis) with 1-4 carbon atoms to form half-esters.

These two reactions are preferred, tertiary amines by the addition of catalytic amounts such as triethylamine, tributylamine and the like accelerated. And be carried out at 80-120 ⁰ C. In general, this takes 1-2 hours or more.

The viscosities of the end products are between 40-152 sec ((DIN 53211) measured 50 wt .- ^ ig in ethylene glycol monobutyl ether) and the acid numbers should be between 60-140.

After the anhydride group has been opened, the Synthetic resins diluted with water-soluble and / or only limited water-soluble solvents. as such are e.g. suitable ethanol, propanol, isopropanol, ethylene glycol monomethyl, ethyl, isopropyl and butyl ether, Methyl glycol tert-butyl ether, as well as butanol, diethylene glycol, Mono- and diether of diethylene glycol, methyl ethyl ketone, methoxyhexanone, diacetone alcohol and Dimethyl sulfoxide.

Smaller proportions of water-insoluble solvents can be used such as xylene, gasoline, cyclohexanol, cyclohexanone, nonanol and decanol can also be used. The total share of solvents should not exceed 30 parts by weight (based on 100 parts by weight of binder solution), the The proportion of water-insoluble solvents should not exceed 20 parts by weight of the amount of solvent used.

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To the obtained resin solution in the water-dilutable state to convert _s it is neutralized almost completely or partially. Ammonia is preferably used for this purpose. Strong organic nitrogen bases whose 10% strength by weight aqueous solutions have a pH of at least 8 are also suitable. For example, amines such as dimethylamine and trimethylamine, triethylamine, diethylamine, propylamine, butylamine, diethanolamine, triethanolamine, N-methylethanolamine _a Ν, Ν-dimethylethanolamine and diisopropanolamine can be used as strong organic nitrogen bases. Alkalis such as sodium hydroxide or potassium hydroxide are also suitable.

All customary pigments, fillers and paint auxiliaries can be used to pigment the binders. Only the use of basic pigments such as zinc oxide needs to be carefully checked in each individual case.

The synthetic resins produced according to the invention are particularly suitable as binders for the electrophoretic Painting process; the electrophoresis baths having a total solids content between 7-20% by weight should.

The synthetic resins produced according to the invention can be used when they are used as binders for paints Find.

However, these paints can also be applied to the objects to be painted by spraying, dipping or flooding will. The stoving temperature after application is between 170-180 ° C for 30 minutes.

In a preferred embodiment of the invention the synthetic resin obtained by the process of the invention

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the components used in the following percentages

contain:

a,) 30 - 40 wt -.% of polybutadiene,

b) 10 -. 30 wt -.% hydrocarbon resin, of which 6-3O wt .- #

c,) from 10 - 25 wt -.% unsaturated oil and -J ^ ™ KWII ⁰

d) 15 -. 20 wt -.% maleic anhydride.

The proportions used depend on the desired properties of the binder. For example, proportions of component b J> 25% by weight ζιιάτ lead to binders with very good throwing power, but the mechanical properties of the films produced are unsatisfactory after stoving. Of component cj> 25 wt -.% Deteriorate generally the corrosion resistance of the films produced by baking. Of component d ^ 20 wt -.% Lead to binders, which have very high conductivities Elektrophoresebäder ₃ which often can be deposited electrophoretically with film defects.

Hydrocarbon resin I (KWI):

Commercially available hydrocarbon resin based on Ethyl or ethylene derivatives of cyclopentadiene, where the synthetic resin has a melting point of 100 ° and has an average molecular weight of 600 and an iodine number of 160. (Escorez ACR-4-100 from Esso).

Hydrocarbon resin II

Commercially available hydrocarbon resin of 36 wt -.% Cyclopentadiene, 15 wt -.% Methyl cyclopentadiene, and 30 parts by weight iS isoprene (Escopol the company Esso.), Average molecular weight 600 and an iodine number 190th

Example 1:

400 g of a polybutadiene with an iodine number of 450 and one average molecular weight of 1400 with 190g des

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Unsaturated, solid hydrocarbon resin I ₃ 60 g of the unsaturated hydrocarbon resin II, 50 g of linseed oil and 100 g of wood oil are mixed. The viscosity of the device is 300 seconds. The mixture is heated under inert gas to IO 2 ^{2 0} C, sec until the viscosity after 4 DIN 53211 630th weight. Then at 160 ⁰ C g maleic anhydride are added at once 200 and maintaining the temperature between l80 190 ⁰ C, until the content of free maleic anhydride virtually zero. Then 64 g of methanol and 0.5 g of triethylamine are added at 80 ° C. and the temperature is increased to 100 ° C. for one hour. Thereafter, the anhydride groups in the adduct are open. Then, the resin Kit Athylenglykolmonoäthylather to a solids content of 70 percent is -. Diluted%.

After neutralization, the synthetic resin is applied electrophoretically in a layer thickness of 25 µ after baking (30 min. At 180 ° C) a paint film with very good corrosion resistance in the salt spray test and good elasticity. The electrophoresis bath has a very good wraparound.

Example 2:

310 g of the polybutadiene described in Example 1, 26 g of the hydrocarbon resin I described in Example 1, 230 g of the hydrocarbon resin II described in Example 1 are mixed with 154 g of linseed oil and 80 g of wood oil, the viscosity of the batch I80 being. amounts to. The mixture is heated under inert gas (COP) at 240 ⁰ C until the viscosity according to DIN 53211 95O sec. Is. It is then cooled to 160.degree. Thereafter, 200 g of maleic anhydride at 16O ° C are added and the reaction is conducted at I80 - 190 ° C as _long} performed until the content of free maleic anhydride practically to zero (in about 4 hours) has fallen. The resin is then at 100 ⁰ C with 64 g of methanol and

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I ₉ O g of triethylamine are added and the mixture is ^{heated at 100 °} C. for 2 hours until all anhydride groups are open. Is then reacted with Äthylenglykolmonornethyläther to a solids content of 70 wt -.% Diluted. The resin obtained after neutralization as a clear lacquer according to electrophoretic application to steel sheets and baking (30 min. At 170 ⁰ C) a hard ₃ in the salt spray test (ASTM B 117-64) corrosion-resistant film. The electrophoresis bath produced from it shows excellent throwing power. The other examples can be found in the following table. The procedure was as in Example 1 or 2, but the raw materials indicated in the table were used in the amounts indicated there.

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Tabel

KWI = Escorez; KWII = Escopol

% By weight of poly

Eeispiel butadiene (viie wt .-% HC resin wt -.% Wt -.% Vorpolynierisiert wt -.% Anhydride

in example 1) linseed oil wood oil at sea. Maleic acid opened with:

(DIN 53211) anhydride

3 40 25 KWI 5 s 10 600 20th Methanol ro 4th 39 24 KWI 17th - 380 20th Methanol 1,349 5 40 12.5 KWI
12.5 KWII 5 10 600 20th Methanol 6th 31.5 6.5 KWI
20.0 KWII 16 6th . 895 20th Methanol 7th 31 2.6 KWI
23.0 KWII 15.4 8th 1020 20th Methanol 8th 30.6 6.3 KWI
19.2 KWII 15.3 8.2 664 20.4 Methanol 9 40 12.5 KWI
12.5 KWII 5 10 890 20th Butanol 10 40 18.7 KWI
6.3 KWII 5 10 895 20th water 11 45 15 KWI 10 10 600 20th Methanol

Wt -.% PolyBeispiel butadiene (as wt -.% In Example 1) HC resin

OI O CD OO CO NJ
"■ ^
O OO CO

Weight 55 oil

12 13

14th

15 16

17th

18th

19 20

21 22 23

Pre-polymerized at sea. (DIN 53211)

Wt -.% Anhydride

Maleic acid opened with: anhydride

40 40

40 40 40

25 'KWI 15 soybean oil

25 KWI 15 tall oil fatty acid triglyceride ester

19 KWI 15 Rüböl 6 KWII

19 KV / I 6 KWII

7.5 soybean oil 7.5 linseed oil

19 KWI 15 peanut fatty acid-6 KVJII triglyceride ester

19 KWI 6 KWII

7.5 linseed oil 7.5 soybean oil

12.5 KWI 15 soybean oil 12.5 KWII

40

Iodine number 105S 1,4-cis-45 lbs 1,4-trans-45 $ 1,2-vinyl MW 1000-1500

40

Iodine number 10% 1,4-cis-45% l _} 4-trans-45 $ 1,2-vinyl-KG

The procedure according to Example 11 The procedure according to Example 11 The procedure according to Example 11 The procedure according to Example 11 The procedure according to Example 11

600 600

800 664 890 890

.800

20th 20th

20th 20th 20th 20th

20th

Methanol methanol

Methanol methanol methanol methanol

Methanol

Ethanol n-butanol sec-butanol isobutanol

n-propanol

Examples 3-18 above were prepared as described in Example 1, however using the aforementioned raw materials with the amounts specified therein.

CD,

subsequently submitted]

Comparative tests to prove the technical progress achieved:

Comparative study A

According to the information in the German Offenlegungsschrift 2 016 223, 400 parts of a polybutadiene with an iodine number of 450 and an average molecular weight of approx. 1400, the double bonds being 65-76 $ 1,4-cis-, 25-35 $ trans- and less than 1% have 1,2-vinyl configuration and I83 T soybean oil to 26O ⁰ C heated until the viscosity (measured 70 wt .- $ in xylene) at 25 to see DIN 53211 (corresponding to 1600 see DIN directly 532II measured) had increased. 10 g of copper naphthenate solution (Cu content 8% by weight) were added and 75 g of maleic anhydride were added. After 40 minutes at 190 ^° C., the batch gelled.

Comparative study B

The procedure was as stated in comparative test A, but the soybean oil was replaced by the same amount of linseed oil. After 30 minutes at 190 ^° C., the batch gelled.

Comparative study C

The procedure was as described in Comparative Test B except that a polybutadiene having an average molecular weight of 1000-150O ₃ an iodine value of 357 and a content of 45 wt .- $ vinyl groups, 45 wt -.% Trans content, and 10 wt .- $ cis content used. After a reaction time of 4 hours at 190 ^° C., the content of unbound maleic anhydride had fallen to zero. The anhydride groups were opened by treating with water and holding at 100 ° C. The synthetic resin obtained was diluted with ethylene glycol monoethyl ether to a solids content of 75% by weight. The resin was mixed with a mixture of the same

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Pigmented 1 and after neutralization with ammonia to a solids content of 13 wt -% diluted * This electrophoresis is against a product made in the same manner bath, the binder in Example: parts of titanium dioxide and aluminum silicate and some soot in the pigment / binder ratio of 0.3. 1 described synthetic resin was added, compared.

Binder according to Ver strong Binder after equality examination C 20/20/14/10 example 1 Through hardening at 20 μ on ^good Well Layer thickness ouch Through hardening dekapier at 25 μ tem insufficient Well Layer thickness stole Waterdrop small amount mark
Wrap around + 20/8/2/0

A 50 cm long, 5 cm wide steel strip inserted so that the distance to the cathode is 2 cm.

It is deposited at such an electrical voltage (volts) that 2 cm from the lower edge on the Steel strips a layer thickness of 20 μ were achieved. The layer thickness is measured at 15 »30 and 45 cm Distance.

The invention also relates to the use of the produced according to the present method, water-dilutable synthetic resins for producing unpigmented _s pigmented and / or provided with fillers thermosetting coating compositions as the sole binder or in admixture with other binders.

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With a special use of the invention
Resins produced v / ground than other binders relatively low molecular weight, at least _s hydrophilic xrärmehärtbare condensation products ₃ as aminoplastbildende reaction products and / or phenolic resoles and / or etherified phenolic resoles for baking type coating compositions
used.

These other binders are in Swiss patent specification 523 929, column 8, line 47 to column 10, Line 19, explained in detail.

In another particular embodiment, such resins are used for the electrophoretic deposition method in which one co-used as other binder phenolic plastic and / or amino resins and these with the results obtained by the method of the present invention, synthetic resins prior to neutralization in the heat at temperatures of 100-150 ⁰ C has combined with precondensation.

Regarding the implementation of the precondensation, refer to the statements in Swiss patent specification No. 523 929, column 10, line 20 to line 57, referenced.

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Claims (1)

Claims Process for the production of thermosetting , water-thinnable synthetic resins suitable for the electrodeposition process on the basis of reaction products of maleic anhydride with mixtures of polybutadiene, unsaturated hydrocarbon resins and unsaturated fatty acid glyceride esters, characterized in that a mixture consisting of: a) 35 ~ 60% by weight of a polybutadiene with an average molecular weight of 750-2000 and an iodine number between 300-45O ₃ b) 10 - 30 wt -. a reactive predominantly aliphatic or cycloaliphatic constructed hydrocarbon resin with a viscosity of between 30% - 800 cP (at 70 # strength solution in toluene at 20 ⁰ C measured), an iodine value of 160-220 (according to ASTM D 555), an average molecular weight of approx. 400 to 700, consisting of b ₁₎ 5-30 -.% Polyisoprene, bp) 30 -. ~ 80% weight cyclopentadiene and / or dicyclopentadiene and / or alkyl or alkylene derivatives of cyclopentadiene, b) 5-15 wt -.% of other mono- or polyunsaturated hydrocarbons having 5 to 12 carbon atoms which are composed predominantly aliphatic or cycloaliphatic, c) 5 - 25% by weight of a fatty acid glyceride ester, wherein each fatty acid residue contains 16 to 18 carbon atoms and the fatty acid glyceride ester has an iodine number between l40 - 220, by heating to 200-270 ⁰ C is prepolymerized until the reaction mixture from the components 509832/0883 th a, b and c, which have an initial viscosity of about 100 to 350 seconds. (measured according to DIN 53211) , Has viscosities between 500 - 2000 sea- (measured according to DIN 53211), then the mixture obtained with d) 15 -% maleic anhydride at l80 - - is reacted 190 ° C until no free Maleinssureanhydrid longer present (the sum of the components a used, b ₃ c and d to 100 weight - 20 wt. necessarily complementary%. ) and e) the anhydride groups contained in the adduct obtained by hydrolysis with water or alcoholysis with the amount of monohydric alcohols with 1-4 carbon atoms required to form half-esters be opened. 2. The method according to claim 1, characterized in that that as component (a) polybutadiene as homopolymers of butadiene with an average molecular weight from 750 to 2000 and iodine numbers between 300 450 can be used. 3. The method according to claim 2, characterized in that as component (a) a polybutadiene with an average molecular weight of about 1400 ₃ an iodine number of 450, the double bond being 65-75% 1.4 cis, 25-35 % 1 , 4 trans and less than 1% 1,2 vinyl configuration is used. 4. The method according to claim 2, characterized in that as component (a) a polybutadiene with an average molecular weight of 1000-150O ₃ an iodine number of 420, the double bond to 10 $ 1.4 cis, to 45 $ 1.4 trans and up to 45 $ 1,2-vinyl configuration is used. 509832/0883 5. The method according to claim 2, characterized in that as component (a) is a polybutadiene with a average molecular weight of 900, an iodine number of 300, 10% of the double bonds being 1.4 cis, to 45 $ 1.4 trans and 45 $ 1.2 vinyl have, is used. 6. The method according to claim 2, characterized in that as component (a) butadiene polymers with terminal Carboxyl or hydroxyl groups are used. 7. A method according to any one of claims 1 to 6, characterized in that as component (b) hydrocarbon resins, which are constructed by polymerization of:.. 5-30 -% isoprene, 30 - 80 wt -% cyclopentadiene and / or dicyclopentadiene and / or alkyl or alkylene derivatives of cyclopentadiene and 5-15 weight -% of other unsaturated hydrocarbons having 5 - 12 carbon atoms, are used.. 8. The method according to any one of claims 1 to J ₃ characterized in that as component (c) triglycerides of unsaturated fatty acid _s, such as tall oil fatty acid, soybean oil fatty acid, linseed oil fatty Your, ricinene fatty acid, wood oil fatty acid, Erdnußfettsäure, rapeseed oil fatty acid, and the like, particularly preferably linseed oil, wood oil and / or castor oil , can be used. 9. The method according to any one of claims 1 to 8, characterized in that that the hydrolysis or alcoholysis at 80-120 ° C by adding catalytic amounts of tertiary Amines carried out faster. 609832/0883 10. The method according to any one of claims 1 to 9 _S, characterized ₃ that by selecting the reactants and the reaction time end products with viscosity values between 40 to 152 sec. ((DIN 53211) measured 50 wt .-% in ethylene glycol monobutyl ether) and acid numbers between 60 - l40 can be produced. 11. The method according to any one of claims 1 to 1O _3, characterized in that after the opening of the anhydride group (by hydrolysis or alcoholysis), the synthetic resins obtained are diluted with water-soluble solvents. 12. The method according to claim 11, characterized in that lower proportions of water-insoluble solvents be used, but the total proportion of solvents is 30 parts by weight (based on 100 parts by weight of binder solution) and the proportion of water-insoluble solvents should be a maximum of 20 parts by weight of the amount of solvent used. 13 · Method according to one of claims 1 to 12, characterized marked that the components in the following percentages a) 30 -. 40 wt -.% of polybutadiene, b) 10 -. 30 wt .-% hydrocarbon st off resin, of which 6-3O wt .-% KWI c) 10 -. 25 wt .-% unsaturated oil and ^{md 6 "3} ° d) 15 -. 20 wt -% of maleic anhydride are used, with the sum of the amounts used are 100 wt -.. has to supplement%. I ¹ J. Use of the water-thinnable synthetic resins produced according to one of claims 1 to 13 for the manufacture 509832/0883 Positioning of unpigmented , pigmented and / or filled thermosetting coating compounds as sole binders or mixed with other binders. 15 · Use according to claim 14, wherein one for the coating composition for the electrophoretic coating process those synthetic resins are used which have acid numbers between 60 and 140. 16. Use according to claim 14, wherein one uses for electrophoretically coating compositions .aufzutragende those which have a total solids content of between 7-20 wt -.% Possess. 17 · Use according to claim 14, wherein the synthetic resins with viscosities between 40 - 152 sec. (DIN 53211), measured 1: 1 in ethylene glycol monobutyl ether at 20 C, used. 18. Use according to claim 14, wherein the other binder is relatively low molecular weight, at least hydrophilic, thermosetting condensation products, such as aminoplast-forming reaction products and / or phenolic resoles and / or etherified phenol resols are also used for stoving coating agents. 509832/0883