JPH0340050B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing water-dilutable polyester. Water-dilutable polyesters whose free carboxyl groups form salts with amine or ammonium bases are known. These polyesters are used for thermosetting coating materials in combination with water-dilutable amine resins, such as melamine and/or urea resins. Such systems generally contain high proportions of organic solvents and therefore pose environmental problems. On the other hand, aqueous polyester solutions with relatively small proportions of organic solvents are known. However, this system has limited storage stability due to its susceptibility to hydrolysis. Furthermore, all of the hitherto known aqueous systems of polyester have the disadvantage that they can only be applied in small layer thicknesses for a bubble-free coating when applied onto the substrate by spraying. have. Furthermore, aqueous dispersions of polymers, such as acrylic polymers containing hydroxyl groups, are known. It can be used for baking coatings in combination with aqueous amine resins such as melamine resins of the type hexamethoxymethylmelamine.
However, this combination is difficult due to unfavorable pigment wetting.
For glossy coatings, only a relatively small proportion of pigment can be applied. This system also requires high proportions of organic solvents to ensure good flow, pigment wetting and other desirable coating technology properties. Therefore it also causes environmental problems. It was therefore desirable to create a water-dilutable system that does not have the drawbacks mentioned above. The subject of the invention is (A) dicarboxylic acid units, (B) at least one polycarboxylic acid monoanhydride, (C) at least one alcohol component comprising at least dihydric alcohol and (D) at least two oxirane rings. Water-dilutable polyesters based on at least one epoxide compound containing
(at least a part of the COOH groups of the polyester are present as ammonium salts), comprising: (a) in the first step 2-100, preferably 2-100
Polyester with an acid value of 30 is an acid component containing at least one dicarboxylic acid or its anhydride.
(A) at least one epoxide compound containing at least two oxirane rings and selected from the group consisting of epoxidized fatty acids, derivatives thereof and epoxidized aliphatic hydrocarbons, or preferably up to 30% (with respect to epoxide groups); (D) and at least one alcohol component (C) comprising at least a dihydric alcohol; , in the second step, a monoepoxide and/or a monoepoxide having at least one ester group in addition to the epoxide group;
or with a polyepoxide to form a polyester with an acid number less than 15, or, if the polyester already has an acid number less than 15, this polyester is optionally converted in a second step to other than the epoxide groups. (c) reacting the polyester formed in the first or second stage with an acid number less than 15 with phthalic anhydride and maleic anhydride; at least one polycarboxylic acid monoanhydride (B) other than
°C, preferably at a temperature between 50 and 140 °C to form the monoanhydride half-ester; (d) in the next step, the liberating half-ester formed
The COOH group is converted into the corresponding ammonium salt by means of an amine, preferably a tertiary amine or a tertiary amine alcohol, and then (e) the product obtained in (d) is then obtained either neat or in a separate step with a solvent. The method is characterized in that it is preferably diluted with water. Advantageously, at least 50%, preferably from 80 to 100%, of the epoxide groups of component (D) in the polyester according to the invention are esterified. Suitable acid components for the starting polyester are, for example, phthalic acid, terephthalic acid, isophthalic acid,
Tetrahydro- and/or hexahydrophthalic acid, halogenated phthalic acids such as tetrachloro-
or tetrabromophthalic acid, and also their endomethylene derivatives such as endomethylenetetrahydrophthalic acid, adipic acid, sebacic acid, fumaric acid, maleic acid or the possible anhydrides of the above-mentioned acids, either individually or in mixtures, optionally mono- Carboxylic acids such as benzoic acid, p-tert.-butylbenzoic acid, lauric acid, isononanoic acid, unsaturated or saturated fatty acids, mixed with naturally occurring oils. Suitable alcohol components of this polyester include polyhydric alcohols such as ethylene glycol, various propanediols, butanediols,
pentanediol, hexanediol, neopentyl glycol, diethylene glycol, cyclohexanedimethanol, trimethylpentanediol, trimethylolethane or -propane, glycerin, pentaerythritol, dipentaerythritol, individually or in mixtures, optionally monohydric alcohols such as butanol, octanol,
It is mixed with lauryl alcohol and linoleyl alcohol. However, each monofunctional compound is used only in a subordinate proportion to the acid or alcohol component. Suitable polycarboxylic anhydrides are trimellitic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, halogenophthalic anhydride, such as tetra- and hexachloro- or bromophthalic anhydride, and also their endomethylene derivatives, such as hexachlor-endo. These are methylenetetrahydrophthalic anhydride, succinic anhydride, and glutaric anhydride. Trimellitic anhydride and/or tetra- or hexahydrophthalic anhydride is preferred. Suitable amine bases for the salt formation of COOH groups of polyester resins according to the invention are, for example, (Here, R ¹ , R ² and R ³ are the same or different, hydrogen atom, aralkyl having 7 to 9 carbon atoms, such as benzyl, 1 to 8 preferably 1
Alkyl having up to 5 carbon atoms, cycloalkyl having up to 6 carbon atoms such as cyclohexyl or hydroxyalkyl having 1 to 5 preferably 1 to 3 carbon atoms. ) or morpholine compounds or quaternary ammonium hydroxides and/or -salts of monocarboxylic acids having 1 to 5, preferably 1 to 3 carbon atoms. Examples include ammonia, trimethyl, triethyl, tributylamine, N-dimethylcyclohexylamine, N-dimethylbenzylamine, dimethylaminoethanol, and diethanolamine. In many cases, it may be necessary to use an excess of the salt-forming organic base relative to the carboxyl group equivalents of the polyester, for example to obtain a given working property. Amines containing hydroxyalkyl groups are preferred. Suitable epoxide compounds (D) are derived from olefinic polyunsaturated fatty acids such as linoleic or linolenic acid. Furthermore, they are derived from esters of olefinically unsaturated fatty acids and polyhydric alcohols, such as esters of oil acids and glycerin. Suitable epoxidized fatty acid derivatives are, for example, those of linseed oil, soybean oil, castor oil, soybean oil, linoleic fatty acids or alkyl esters of arachidonic acid, oligomeric fatty acids and their esters. Epoxidized linseed oil and soybean oil are preferred. However, it should be noted here that in the one-step reaction with polyepoxides, preferably only those having at least one ester group next to the epoxide groups (optionally together with monoepoxides) are taken into account. Examples of epoxidized aliphatic hydrocarbons include those having 4 to 20, preferably 4 to 12 carbon atoms and 2 to 6, preferably 2 to 4 oxirane rings per molecule, such as epoxidized polybutadienol. , their C-alkylated products such as isopropenol or homologs of these substances come into consideration. The proportion of epoxide compounds can be, for example, from 5 to 40% by weight, preferably from 10 to 30% by weight, based on the final product. Optionally, the polyester can also be made on the basis of at least one bound monoepoxide. Suitable monoepoxides are, for example, ethylene, propylene, butylene oxide, styrene oxide, cyclohexene vinyl monooxide, dipentene monooxide, α-pinene oxide, and also butyl glycidyl ether, allyl glycidyl ether, phenyl glycidyl ether, p- Epoxies such as butylphenol glycidyl ether, cresyl glycidyl ether, 3-(pentadecyl)-phenol-glycidyl ether, and also glycidyl esters of saturated monocarboxylic acids, e.g. mono- or doubly branched in the alpha position, or glycidyl methacrylate. It is a carbonized hydrocarbon. The process proceeds smoothly and the product made in this way has the advantage that it has a surprisingly relatively low propensity to hydrolysis upon storage in aqueous media. . Furthermore, it is compatible with water-soluble or water-dilutable mono- and polyepoxides and water-soluble amine resins. Preferably, the reaction is carried out in step (c) with trimellitic anhydride and/or with anhydrides of at least partially hydrogenated aromatic dicarboxylic acids such as hexa- and/or tetrahydrophthalic anhydrides. It will be done. The condensation in step (a) is usually carried out at a temperature of at least 170°C, preferably from 190 to 230°C. In this case, this temperature range is preferred because the reaction between the carboxyl group of the polycarboxylic acid (A) and the epoxide group of the epoxide compound (D) proceeds smoothly and completely. In the modified polyester produced by this method,
Epoxide compounds are incorporated into the polymer chain via epoxide groups. The polyepoxide used in step (b) is
The ones mentioned above are suitable. According to an advantageous embodiment of the invention, in the first step, in addition to the acid component and the alcohol component mentioned under symbol (a) and the epoxide groups in an amount such that the polyester has an acid number of less than 15, Polyesters can be made from epoxide compounds in the form of polyepoxides having at least one ester group, alone or in mixtures with at least one monoepoxide (D). The method then skips step (b) and proceeds to step (c). This polyester can be prepared in water without the addition of solvents.
It can be diluted arbitrarily without agglomeration. Nevertheless, it resists hydrolysis. It can therefore advantageously be present in the form of an aqueous solution, optionally in a mixture with water-soluble or water-insoluble solvents. Aqueous solutions of polyester according to the invention are generally clear to milky cloudy;
of low to high viscosity depending on its chemical composition,
It is a liquid with excellent storage stability. Its solids content can vary within a wide range. But it is
It can also have paste-like properties. it is,
High proportions of pigments and/or fillers can be mixed. Polyesters exhibit particularly good crosslinking properties here. The polyester according to the invention or the product obtained by the process according to the invention can surprisingly be used with certain water-dilutable epoxides, especially polyepoxides alone, or with amine resins, especially those of the water-dilutable type, including hexamethoxymethyl melamine. Because it is compatible with combinations with types such as urea resin,
It can be used as a binder in an aqueous medium or in a water-compatible medium, optionally alone or in combination with such water-reducible amine resins and/or with such epoxides. In particular, the polyester according to the invention is free of glycidyl ester groups and glycidyl ether groups and, in addition to at least one epoxide group, has at least one ester group of a monocarboxylic acid and another OH group adjacent thereto. The second COOH, which contains an ester group resulting from reaction with a carboxylic acid monoanhydride and is formed from the anhydride during esterification, is modified such that it is present wholly or partly in the form of a salt of the base. Epoxide (see West German patent publication P31099009)
It is compatible with The weight ratio of the polyester resin according to the invention to the crosslinking partner, such as a water-dilutable amine resin and/or epoxide, can vary within a wide range, such as 99:1.
-1:99, preferably from 90:10 to 50:50. In accordance with an embodiment of the present invention, the crosslinking material combination of water-reducible amine resin and water-reducible epoxide, preferably polyepoxide, is from 90:10 to 10:
90, especially in a weight ratio of 50:1 to 10:50. Particularly valuable products are obtained by the inventive modification of polyesters by introducing epoxide compounds. It is cured by the addition of suitable crosslinking substances, such as amine resins and/or water-dilutable epoxides, resulting in organisms with high mechanical strength, high elasticity and chemical resistance. This product can be affected by weather effects such as UV light,
Alkali, organic solvents such as acetone, alcohols, aromatic compounds such as benzene, toluene,
Resistant to xylene. By means of binders made from polyesters according to the invention coating materials such as paints can be made with or without pigments or with the addition of other fillers. After curing, this results in a coating with excellent mechanical properties. The polyesters according to the invention are used in particular for the production of hardened coatings, especially coatings that are baked at temperatures above 60.degree. Often under mild conditions, i.e. 60-120°C, of course e.g. 120°C
Higher temperatures above suitably result in better crosslinking. Higher temperature e.g. 140-190
℃ can significantly shorten the curing time. The products according to the invention can be cured under rapid drying conditions, such as those used for example in coil coatings or can coatings, i.e. at 200-350° C. for extremely short times, for example 10 seconds to 3 minutes; An excellent coating can be obtained. If the mixture contains a water-reducible epoxide to promote crosslinking or to reduce the curing temperature,
Up to 10% by weight based on solids content, preferably
It may be advantageous to add the catalyst in a proportion of 0.01 to 5% by weight. For example, basic catalysts such as diazabicyclooctane, diazabicyclononene or -undecene, imidazole derivatives such as 3-
Methyl-2-phenol- or cyclohexylimidazole, trialkylamines such as triethyl-, tributyl-, tricyclohexylamine, N-alkylpiperidines, N,N'-dialkylpiperazines, trialkyl- or triall-phosphines, N,N' -tetraalkylaminoalkyl-oxamides, N-dialkylaminoalkyl-oxamic acid alkyl esters, and also amines, hydroxides, carbonates and alkali metal salts of organic acids, such as lithium hydroxide, potassium carbonate, lithium benzoate, and , with crown ethers or other ligands are suitable. However, alkali and/or alkaline earth metal salts of polymeric acids, such as those described in West German patent application P 304 16 536, and quaternary ammonium compounds such as choline, tetrabutylammonium iodide, etc. , -chloride, -bromide, -hydroxide, tetramethylammonium-chloride, -bromide, -iodide, -hydroxide are also effective catalysts for the coating material according to the invention. A particular advantage of the invention is that the polyester-based system according to the invention makes it possible to obtain highly elastic coatings with a problem-free surface, i.e. without bubbles after the curing process even in the case of relatively high layer thicknesses. It is. It is also possible to combine the polyesters according to the invention with polymer dispersions, such as dispersions of acrylic polymers containing hydroxyl groups, and to crosslink them with water-dilutable amine resins and/or water-dilutable polyepoxides. Systems of this type can be applied without difficulty to give cured coatings with a problem-free appearance and excellent coating technical properties. The polyester-based combinations according to the invention consisting of polyester and modified epoxide and/or amine resins as crosslinking substances can be applied on various substrates, as long as the substrates withstand the curing temperature of the coating. Suitable substrates include, for example, ceramic, wood,
glass, concrete, synthetic resins, preferably metals such as iron, zinc, titanium, copper, aluminium, steel, brass, bronze, magnesium, etc., the substrate optionally also having suitable mechanical and/or It can be rendered adhesively compatible or corrosion resistant by chemical pretreatment. However, the coatings according to the present invention adhere significantly to various metal substrates without an adhesion-mediating substrate or intermediate layer. Good adhesion of this coating corresponds to a value of GTOA to GT1A of the test standard according to DIN 53151. The aqueous polyester combination according to the invention comprises:
They are particularly suitable as resistant paints and matte paints, for the production of corrosion protection coatings and/or intermediate coatings in various fields of use. Furthermore, it is suitable for coating and lining objects that come into contact with fuels and solvents, and also for protective coatings against atmospheric influences, e.g. for electrical engineering purposes, components or their elements, in particular electrical conductors. , as well as for coating objects that receive heat. Due to their desirable properties, the polyester combinations according to the invention are also eminently suitable for single-coat coatings. Depending on the selection of the components, the sheet metal coated with the material according to the invention can be subsequently deep-drawn,
It can be shaped by bending, cross-sectioning, stamping, etc. without any significant adverse effect on the desired properties mentioned above. The adhered covering layer remains unchanged. However, it can also be used as an intermediate layer and as a base layer for other coatings, the latter also being able to consist of the same itself or of other customary coating materials. The resulting coating yields an optionally glossy or matte film with excellent mechanical and chemical resistance and good weather resistance. On the other hand, it is also possible to make matte paints with excellent mechanical and chemical properties. For this purpose, surprisingly high proportions of pigments and fillers are not required. A further use of the above-mentioned combinations of polyesters according to the invention is their properties as crosslinkable resins with emulsifying action or as protective colloids, thickeners, thixotropic agents for the dispersion of polymerized and condensed synthetic resins. It's in the characteristics. Owing to its good dilutability and other desirable properties, this combination is also suitable for use for electrocoating. Furthermore, the polyester combination according to the invention can be used for water-dilutable adhesives. It can also be used as a binder for fibrous organic and/or inorganic materials. They are also suitable for curable moldings, casting resins, putties, cellular or porous materials such as sponges, and as insulating materials. In the following examples, unless otherwise specified, T means parts by weight, % means % by weight, SZ means acid value, and OHZ means hydroxyl value. As a monoepoxide, 10~
Glycidyl esters of α-branched monocarboxylic acids with 12 carbon atoms are used. Example () Preparation of polyester (1A) In two glass flasks equipped with a reflux condenser, a water separator, a stirrer, a contact thermometer and a heating device, 732T of phthalic anhydride,
572T neopentyl glycol, 55T trimethylolpropane, 130T epoxidized soybean oil with an epoxy equivalent weight of 260 and 80
Charge ~100T of toluene and heat to 220 °C under an inert gas atmosphere under light reflux. After about 8 hours, a polyester with SZ15 is obtained. Subsequently, the mixture is cooled to 120°C, and after distilling off toluene, 96T monoepoxide is added.
After a further 4 hours at 120°C, the reaction mixture is cooled to room temperature. The SZ of the product is
Here <2. (1B) In two glass flasks equipped with a reflux condenser, a contact thermometer, a heating device and a stirrer, 300 T of the obtained polyester and
28.1 T of trimellitic anhydride under an inert gas atmosphere until an acid number of approximately 50 is achieved.
Heat at 120-130°C for 3-4 hours. The mixture is then cooled to 90° C. and 22.7 T dimethylaminoethanol is added. The reaction mixture is then diluted with 350T deionized water.
A clear solution with pH=6.1 and solids content of 50% is obtained. (2) In the reaction vessel used in (1A), 722T of phthalic anhydride, 578T of neopentyl glycol,
36.7T trimethylolpropane and 173.3T
Epoxidized soybean oil (see section (1A)) is reacted in the same manner as in (1A). Obtain SZ14 polyester. After reaction with 89T monoepoxide, the polyester has SZ<2. 600T of the polyester is reacted with 56.2T of trimellitic anhydride in the same manner as in (1B) until SZ51 is obtained.
Salt formation is then carried out with 45.4T dimethylaminoethanol. Dilute with water to make a 55% clear resin solution (PH 7). (3) React 682T phthalic anhydride, 579T neopentyl glycol, 37T trimethylolpropane, and 173T epoxidized soybean oil (see (1A)) to SZ15 according to (1A).
Then reacted with 94T monoepoxide.
Obtain polyester of SZ1.6. This polyester 600T is reacted with 56T trimellitic anhydride as shown in (1B). The product (SZ51) is subsequently salted with 46T dimethylaminoethanol and adjusted to a solids content of 55% with deionization. This aqueous polyester solution is clear and has a pH of 6.6. (4) From 722T phthalic anhydride, 579T neopentyl glycol, 75T trimethylolpropane, 251T epoxidized soybean oil (see (1A)) and 105T monoepoxide, according to Example 1, SZ< 2. Make OHZ107 polyester. This polyester 600T 56T
and trimellitic anhydride in the same manner as (1B). The reaction mixture (SZ50) is subsequently salted with 46T dimethylaminoethanol and adjusted to a solids content of 55% with deionized water. This aqueous polyester solution is clear and has a pH of 7.6. (5) From 722T phthalic anhydride, 579T neopentyl glycol, 150T trimethylolpropane, 251T epoxidized soybean oil (see (1A)) and 108T monoepoxide,
Make polyester of SZ2 and OHZ168. Make this polyester 600T like (1B)
React with 56T trimellitic anhydride. The product has SZ51. Salt formation is then carried out with 45T dimethylaminoethanol. Dilute to 55% solids content with deionized water. This resin solution is clear and has a pH of 7.2. (6) From 762T phthalic anhydride, 667T neopentyl glycol, 317T isoalkyl epoxy stearate (epoxy equivalent = 500),
Make SZ12.5 polyester and then
Reacted with 100.9T monoepoxide, SZ<2,
Obtain the product OHZ93. This polyester
300T is reacted with 31T trimellitic anhydride in the same manner as in Example 1 to obtain SZ56 polyester. Salt formation is then carried out with 23T dimethylaminoethanol. Dilute to 50% solids content with deionized water. The polyester solution is opaque to slightly cloudy and has a pH of 6.4. (7) Similarly to (1A) from 732T phthalic anhydride, 572T neopentyl glycol, 27.5T trimethylolpropene, 20.9T pentaerythritol, 130T epoxidized soybean oil (see (1A)). Make SZ16.1 polyester, then 102T monoepoxide, and SZ
React until <2. This polyester
300T is reacted with 28T trimellitic anhydride as in Example 1 to obtain the product SZ48. Salt formation is then carried out with 22.7T dimethylaminoethanol. Solids content in deionized water
Dilute to 50%. This polyester is opaque to slightly hazy and has a pH of 7.5. (8) 732T phthalic anhydride, as in Example 1;
A polyester of SZ14 is made from 572T neopentyl glycol, 55T trimethylolpropane, and 130T epoxidized linseed oil (epoxy equivalent weight 179), followed by reaction with 89T monoepoxide to give SZ<2. This polyester 300T is reacted with trimellitic anhydride as in Example 1. Further processing according to Example 7. The 55% aqueous polyester solution is cloudy and has a pH of 6.9. (9) Monoepoxide reaction product from Example 3
600T is reacted with 89T hexahydrophthalic anhydride to give SZ49 according to (1B). Salt formation is then carried out with 44T dimethylaminoethanol. Dilute to 55% solids content with deionized water. This aqueous polyester solution is opaque to slightly cloudy and has a pH of 7.1. (10) Monoepoxide reaction product from Example 2
600T is reacted with 60.2T of succinic anhydride according to (1B). The SZ50.8 reaction mixture is subsequently salted with 45T dimethylaminoethanol and adjusted to a solids content of 55% with deionized water. This aqueous polyester solution is opaque to slightly cloudy and has a pH of 7.3. (11) As in Example 1, 732T phthalic anhydride, 572T neopentyl glycol, 55T
trimethylolpropane, 134T epoxidized polybutadienol (epoxy equivalent weight 267)
Make polyester of SZ14.5 from
Reaction with monoepoxide of 97T gives a product with SZ<2. Example 1: 300T of this product
React with 28.3T anhydrous trimerite as shown below. The reaction product of SZ51.2 is subsequently salted with 23T dimethylaminoethanol and adjusted to a solids content of 50% with deionized water.
This aqueous polyester solution is opaque to slightly cloudy and has a pH of 6.3. (12A) In two glass flasks equipped with a reflux condenser, a water separator, a stirrer, a contact thermometer, and a heating device, add 702T of phthalic anhydride,
579T neopentyl glycol, 75T trimethylolpropane, 211T epoxidized soybean oil (epoxy equivalent weight 260) and 80~
Add 100T of toluene and heat under light reflux in an inert gas atmosphere until the acid value reaches approximately 15.
Heat at 200 °C (reaction time approximately 11-12 hours). Subsequently, epoxidized soybean oil with an epoxy equivalent weight of 260 is added. After a further 4 hours at 200°C, the reaction mixture is cooled to room temperature. The acid number of the product is approximately 4. (12B) In two glass flasks equipped with a reflux condenser, a contact thermometer, a heating device and a stirrer, the obtained polyester 700T and 60T of trimellitic anhydride were mixed under an inert gas atmosphere to an acid value of about 50. 120-130℃ until obtained
Heat for 3 to 4 hours. Then mix the mixture
Cool to 90°C and add 53T dimethylaminoethanol. The reaction mixture is subsequently diluted with 663T deionized water. clear,
A solution with a pH of 6.9 and a solids content of 55% is obtained. (13) In the reaction vessel of (12A), 722T of phthalic anhydride, 579T of neopentyl glycol, 75T of trimethylolpropane and 211T of epoxidized soybean oil (see (12A)). react. A polyester with an acid value of 13.7 is obtained. After reacting with 110T epoxidized soybean oil as in (12A), the polyester
It has an acid value of This polyester 700T is reacted with 60T trimellitic anhydride in the same manner as (12B) until the acid value reaches 51. Salt formation is then carried out with 52.8T dimethylaminoethanol. Dilute with deionized water to make a 50% solution (PH6.5). (14) In a reaction vessel such as (12A), 702T of phthalic anhydride, 579T of neopentyl glycol, 75T of trimethylolpropane and
291T epoxidized soybean oil (see (12A))
is reacted in the same manner as (12A). acid value
15 polyesters are obtained. After reacting with 111T epoxidized soybean oil in the same manner as (12A), the polyester
It has an acid value of 5.6. This polyester 700T is reacted with 58T trimellitic anhydride until the acid value reaches 50 in the same manner as (12B). Salt formation is then carried out with 53T dimethylaminoethanol. Dilute with deionized water to make a 55% solution (PH6.4). (15) 722T phthalic anhydride, 579T neopentyl glycol, 75T trimethylolpropane, 211T epoxidized soybean oil (see (12A)) and 82T castor oil fatty acid, (12A)
React in the same way. A polyester with an acid value of 15.4 is obtained. In the same way as in (12A) and further
After reacting with 110T epoxidized soybean oil,
A polyester with an acid value of 6.8 is obtained. This polyester 700T is reacted with 56T trimellitic anhydride until the acid value reaches 52 as in (12B). Salt formation is then carried out with 53T dimethylaminoethanol. Dilute with deionized water to make a 55% solution (PH6.8). (16) In the same reaction vessel as (12A), 722T phthalic anhydride, 579T neopentyl glycol, 75T trimethylolpropane, 211T
epoxidized soybean oil (see (12A)) and
82T isononanoic acid is reacted in the same manner as (12A). A polyester with an acid value of 15.7 is obtained. After reacting with 110T epoxidized soybean oil in the same manner as (12A), the polyester was 4.3
It has an acid value of This polyester 700T is reacted with 60T trimellitic anhydride in the same manner as (12B) until the acid value reaches 49.4. Salt formation is then carried out with 53T dimethylaminoethanol. Dilute with deionized water to make a 50% solution (PH6.7). (17) In a reaction vessel like (12A), 682T phthalic anhydride, 579T neopentyl glycol,
75T trimethylolpropane and 321T epoxidized soybean oil (epoxy equivalent weight 260) and
Charge 80-100T of toluene and heat to 220 °C in an inert atmosphere under light reflux. After 24 hours of reaction, the reaction mixture is cooled to room temperature. The acid value of polyester (after removal of toluene) is
It is 4.9. 600T polyester (12B) and so on
React with 51T phthalic anhydride until the acid value reaches 49.8. Salt formation is then carried out with 45T dimethylaminoethanol. Dilute to 55% solution (PH6.6) with deionized water. In the following examples a 50% polyester solution is used in each case. As the epoxide component, a 40% solution of epoxide, preferably polyepoxide, is used. For this purpose, modified epoxides such as those described in West German patent application no. used. Melamine resin consists of hexamethoxymethylmelamine. () Preparation of coatings 18-24, 27-29 and 32-40 Examples 18-24, 27-29 and 32-40 are carried out as follows (see Table 1). The indicated amount of the solution of the polyester according to the invention is mixed with the indicated amount of the aqueous solution of the polyepoxide. Subsequently, an amount of titanium dioxide corresponding to the total solids content of the mixture is added and the mixture is ball milled. Then add melamine resin to the mixture, homogenize, and then use deionized water in a 4 mm DIN beaker (according to DIN53211).
Adjust to a spraying viscosity of 18 seconds. After standing for three days, the paint is sprayed onto the phosphate-treated steel plate using a spray gun. This coated specimen was first heated at room temperature.
Evacuate for 20 minutes. Next, curing is performed under the curing conditions shown in Table 2. 25 and 30 Examples 25 and 30 are carried out similarly, except that the pigment dispersion is carried out only in the polyester resin medium. The dry thickness of the coating is in all cases approx.
It is 40 μm. 26 50T of 50% polyester solution from Example 3
is mixed with 62.5 T of an aqueous epoxide solution according to example 1 of the West German patent application P31099009 below and adjusted to pH=1 with dimethylaminoethanol.
Adjust the PH value to 8.0. Next, mix 100T of titanium dioxide. The mixture is ball milled. Subsequently, based on butyl acrylate, methyl methacrylate, hydroxyethyl acrylate and acrylic acid,
100T of a 50% dispersion of acrylate with hydroxyl and carboxyl groups is mixed with 10T of hexamethoxymethylmelamine. The mixture was diluted with deionized water in a 4 mm DIN beaker for 18 hours.
Adjust the flow time to 1 second and spray on the steel plate (Erichsen plate). 31 The paint is prepared as in Example 12 and subsequently adjusted with deionized water to a 90 second flush time in a 4 mm DIN beaker. This coating material is applied with a doctor blade to a wet film thickness of 100 .mu.m on a phosphated metal plate. Then, it is immediately rapidly dried in an air exchange oven at 300° C. for 1 minute without evacuation. 41 (Two-layer metal effect coating) First, 50% polyester solution according to Example 4
150T, 100T of 40% epoxide aqueous solution according to Example 8 of West German Patent Publication P31099009 mentioned below
and make a mixture from aluminum pigment 29T,
and 15 in a 4 mm DIN beaker with deionized water.
Dilute to give an outflow time of seconds. This solution is sprayed onto a steel plate as a basecoat to a pre-drying thickness of about 100 μm and, after evacuation for about 15 minutes, cured at 110° C. for 30 minutes. After cooling of the subbing layer, a mixture of 110T of the 50% polyester mixture of Example 3 and 15T of hexamethoxymethylmelamine was coated with 4 mm of deionized water.
Spray the adjusted mixture onto the basecoat layer in a DIN beaker with a run-off time of 18 seconds to give a clear coverage and after 10 minutes of evacuation at 140 °C for 30 minutes.
Cure for minutes. A problem-free, highly glossy and scratch-resistant two-coat metal effect coating is obtained.

[Table] () Coating technical test Table 2 summarizes the curing conditions and measured test values. In addition to the test values shown in Table 2, the T-bend test (ECCA standard) for Example 25 after rapid drying
Values of T ₁ and 2H pencil hardness ASTMD 3363-74 were obtained. () Discussion of the results As the values in Table 2 show, the coatings of all examples give good coating technical properties. According to the selected combination of polyester and polyepoxide, extremely high surface hardness (Examples 20, 25, 30,
See 32, 33 and 38. ) and extremely high crosslinking density and therefore high chemical resistance (Example 20,
See 25, 31 and 35. ) is obtained. Furthermore, all crosslinked samples show good impact deformability. This is significantly higher in certain combinations (see Examples 24, 27, 31, 36, 37 and 39). Example 25 despite the curing time of only 1 minute
According to this method, a coating with high surface hardness and high deformability can be obtained.

[Table] Example 1 of West German patent application P31099009:
In a flask equipped with a reflux condenser, a stirrer, a thermometer and a heating device, a solution consisting of 245 T epoxidized soybean oil (epoxy equivalent weight 260), 0.26 T lithium hydroxide and 16.5 T acetic acid was heated to 100°C. at 15
Heat under gentle reflux for an hour. After that the acid value is 4. The mixture is cooled to 50°C. Then add 30.8T of phthalic anhydride and 21T of water-free triethylamine. After 4 hours at 50°C, the acid number is 52. Then dilute with 470T deionized water. PH＝
7.8, 40% solids, an opaque solution of EAG492 is obtained. Same as above 4: Repeat Example 2, but heat at 110° C. for 4 hours. After that the acid value is 0.7. The mixture is cooled to 50°C and 24.5T maleic anhydride and 25.3T triethylamine are added. 3 at 50℃
After an hour reaction, an acid number of 50 is achieved, followed by
Dilute with 467T deionized water to give a cloudy, opaque solution with PH=7.2: EAG505. 6: Intermediate A: 1470T of the epoxidized soybean oil of Example 1 was refluxed with 99T of acetic acid and 3T of tetrabutylammonium hydroxide.
Heat at 110°C for 6 hours. Acid value is 1.6. Intermediate B: 308T hexahydrophthalic anhydride and 192T trimellitic anhydride are melted at 160°C and cooled to 100°C. from the dropping funnel
Carefully add 101T triethylamine. 500T intermediate product A, 68.7T intermediate product B,
35.1 T of phthalic anhydride and 43.2 T of triethylamine are first reacted for 45 minutes at 70° C. under stirring in a flask equipped with a reflux condenser. The mixture is then allowed to react for a further 3 hours at 50° C. until an acid number of 60 is reached. Then dilute to 40% with 970T deionized water and adjust the pH to 8.5 with dimethylaminoethanol. A clear solution is obtained; EAG640. Same as above 8: In the reaction vessel of Example 1, 440T of epoxidized linseed oil of Example 1, 33T of acetic acid and
0.5 T of chromium() octoate is heated at 110° C. for 4 hours until an acid number of 0.25 is obtained. After cooling to 80°C, 97.5T hexahydrophthalic anhydride and 5.8T tripropylamine are added and heated at 80°C for 10 hours until an acid number of 50.6 is reached. followed by 917T
of water and 34.8T of dimethylaminoethanol to make a 40% solution. The pH value is 8.8 and the solution is opaque; EAG362. Example 1
Heat at 110° for 4 hours in the same apparatus until the acid value reaches 2. Subsequently it is cooled to 60°C, 20T diethylisopropylamine and 55.4T succinic anhydride are added and the mixture is kept at 60°C for 8 hours until the acid number is 50. Then dilute to 40% with 870T deionized water and adjust the pH value to 8.0 with dimethylaminoethanol. A transparent to slightly opaque product is obtained; EAG487. 10 as above: Intermediate product: 450T of epoxidized linseed oil (EAG=180) and 450T of epoxidized soybean oil are mixed with 59.6T of acetic acid and 0.5T of chromium() octoate anhydride under stirring and light reflux. Heat at 100℃ for 5 hours until the value reaches 2. 450T of intermediate product and 44.5T of succinic anhydride and 20T of diethylisopropylamine are reacted at 60° C. for 8 hours until the acid number is 50. Next, prepare a 40% solution at pH=7.5 with 772T deionized water and dimethylaminoethanol. The solution is opaque; EAG430. 11 as above: Epoxidized linseed oil of Example 10
950T, 160.4T lysinene fatty acid, 50T acetic acid and 1T tetrabutylammonium hydroxide are reacted at 110° C. under stirring and reflux until the acid number is 3. Then 257.3T of tetrahydrophthalic anhydride and 15T of pyridine are added and the mixture is reduced to an acid value of 50.
Keep at 70℃ until Dilute 2126T with deionized water to make a 40% solution and dilute with dimethylaminoethanol.
Adjust to PH=9.5. The solution is opaque;
EAG356. 12 as above: Intermediate products: 700T epoxidized soybean oil, 200T 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexane carboxylate (EAG=140), 56.8T acetic acid and
Heat 2T of chromium() octoace at 110℃ for 3 hours. Acid value is 0.6. 450T intermediate product and 44.5T succinic anhydride and
15T triethylamine (anhydrous) is reacted at 60°C for 8 hours until the acid number reaches 50. Dilute the product to 40% with 764T water and then adjust the pH to 8.2 with dimethylaminoethanol. Obtain an opaque solution; EAG420.

Claims (1)

[Claims] 1 (A) dicarboxylic acid units, (B) at least one polycarboxylic acid monoanhydride, (C) at least one alcohol component containing at least dihydric alcohol, and (D) at least two oxiranes. Water-dilutable polyesters based on at least one epoxide compound containing rings, provided that
(a) In the first step, a polyester having an acid value of 2 to 100 is treated with an acid component (containing at least one dicarboxylic acid component). A), at least one epoxide compound containing at least two oxirane rings and selected from the group consisting of epoxidized fatty acids, derivatives thereof, and epoxidized aliphatic hydrocarbons, or a mixture thereof with a monoepoxide (D); (b) If the polyester has an acid number of at least 15, the polyester is then further processed in a second stage in addition to the epoxide groups. monoepoxide with at least one ester group and/or
or with a polyepoxide to form a polyester with an acid number less than 15, or, if the polyester already has an acid number less than 15, this polyester is optionally converted in a second step to other than the epoxide groups. (c) reacting the polyester formed in the first or second stage with an acid number less than 15 with phthalic anhydride and maleic anhydride; at least one polycarboxylic acid monoanhydride (B) other than
reaction at a temperature of
converting the COOH group into the corresponding ammonium salt with an amine, and then (e) subsequently obtaining the product obtained in (d) as such or diluting it with a solvent in a separate step, Said method. 2. The process according to claim 1, wherein in step (c), trimellitic anhydride and/or an at least partially hydrogenated anhydride of an aromatic dicarboxylic acid is used as component (B). 3. The method according to claim 1 or 2, wherein the polyester condensation reaction in step (a) is carried out at a temperature of at least 170°C. 4 In the first step, as the epoxide compound (D), an epoxide compound in the form of polyepoxide having at least one ester group in addition to the epoxide group alone or a mixture thereof with at least one monoepoxide is used in the first step. at 15
4. A process according to any one of claims 1 to 3, used in such an amount that a polyester with a lower acid number is produced.