JPS6241545B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a process for producing aqueous emulsions for air-drying or baking paints based on polyethylene glycol-modified alkyd resins with improved long-term stability. In this method, a fatty acid ester having ether-like linked polyethylene glycol groups is reacted with a conventional alkyd resin raw material to obtain an alkyd resin intermediate, which is then esterified with methacrylic acid and an acidic vinyl copolymer having fatty acid groups in the next step. Polyglycol content is 3-8
The reason why the product has excellent stability properties despite the relatively low % is due to the fact that the binding of the stabilizing group is substantially unsaponifiable. A number of patent specifications describe the preparation of water-emulsifiable alkyd resins by modification with polyethylene glycol (PEG). Most methods incorporate approximately 10-30% PEG into the alkyd by transesterification or esterification. (Among others, U.S. Patent Specification No.
No. 2634245, No. 2853459, No. 3133032, No. 3223659, No. 3379548, No. 3437615,
Same No. 3437618, Same No. 3442835, Same No. 3457206
No. 3639315, German Publication Specification No. 1495032
or British Patent Specification No. 1038696 and British Patent Specification No.
(See No. 1044821). Introduction of PEG by esterification has two significant drawbacks. That is, the hydroxyl groups of 1 PEG can only react in the same proportion as the hydroxyl groups of other polyols. Water-dilutable resins are prepared with an excess of hydroxyl groups, leaving PEG incorporation incomplete. Therefore, an excess of PEG must be used, which necessarily reduces the hardness and water resistance of the coating. 2 The attached ester bridge is immediately adjacent to the hydrophilic PEG chain. They are therefore susceptible to direct attack by water in emulsions, and the storage stability of the emulsions is therefore poor. Many attempts have been made to improve the storage stability of emulsions by other methods of introducing PEG. According to US Pat. No. 4,179,428, baking paints are prepared by etherifying the amine-formaldehyde resin and PEG in a first step and then combining it by reaction of its excess functional groups with an alkyd resin intermediate. An alkyd resin is produced that can be diluted with water. According to European Patent Application No. 0002488A1, an air-drying alkyd resin emulsion is produced in a three-step process. According to this, PEG is first reacted with an excess of low-molecular-weight alkylphenol resol,
The remaining methylol groups of the resol are then reacted with the drying oil to form a chroman ring bond between the resol and the oil. The PEG-modified oil thus obtained serves as the starting material in the production of water-emulsifiable alkyd resins. In either case, almost complete incorporation of PEG is achieved by two or more reaction steps, and therefore the amount required is relatively small. Furthermore, as expected, by replacing the easily esterified ester linkage by a more stable N-methylol-ether linkage or a practically unsaponifiable phenol-methylol-ether linkage, Storage stability can be substantially increased. According to the method described, emulsions are produced which exhibit good coating properties and can be stored under convenient conditions, for example at temperatures of the order of /20 DEG C., for one year. However, it is necessary to further improve storage stability for the following reasons. 1. The rheological properties of emulsions are subject to severe changes during storage. Immediately after preparation, the emulsion has a structural viscosity and thus results in a thixotropic paint with little tendency to sedimentation. During storage, the structure breaks down, resulting in a continuous decrease in viscosity at low shear rates. Because of these changes, storage emulsions present stability problems in handling and in the preparation of coatings from the emulsions. 2. Storage stability is highly dependent on temperature. An increase of 10 or 20°C results in a significant decrease in viscosity and coagulation. In countries with warm climates, storage can only be done in rooms with controlled humidity and temperature. 3. If the paints prepared from emulsions require long-term durability, for example in the case of refinish paints, a total storage period of one year is insufficient. There is therefore a strong need for alkyd resin emulsions that can be stored for long periods of time and have excellent coating properties that do not undergo changes on storage with respect to their rheological properties. It is hypothesized that the good storage stability of the emulsions produced according to European Patent Application No. 0002488 and Austrian Patent Specification No. 339450 is due to the hydrolytic removal of the terminal carboxy groups. Carboxy groups are introduced by partial esterification of aromatic or aliphatic di- or tricarboxylic acids, such as o-phthalic acid, tetrahydrophthalic acid or trimellitic acid. They are neutralized to provide the necessary negative charge to stabilize the emulsion droplets. Depending on the extent to which they are removed, the emulsion becomes coarser and thinner and eventually solidifies. It is known from the literature that the stability of acidic partially esterified bonds against saponification increases with the distance between the ester group and the carboxy group, ie, with the number of carbon atoms. 2 (e.g. phthalic acid)
Alternatively, improvement can be expected when more than three carbon atoms (for example, trimellitic acid) are present between the ester bond and the carboxy group. Attempts have therefore been made to obtain more stable emulsions by using addition compounds of acrylic or methacrylic acid to unsaturated oil fatty acids to introduce carboxy groups. According to DE 2416658, adducts are prepared by reaction of acrylic or methacrylic acid with conjugated unsaturated fatty acids at 250-300°C, which are treated by esterification according to known methods. PEG-modified water-emulsifiable alkyd resin. A disadvantage of this method is that since the polyethylene glycol is incorporated by esterification, it is easily reseparated. High PEG content is required to obtain sufficient stability of the emulsion.
(5-15%, in the example 8.5-9.5%) should be used. Furthermore, the conditions cited produce adducts with up to 15% acrylic acid, while 17-45% of the acrylic or methacrylic acid used.
remains in the final reaction and must be removed by distillation. Considering that an acid value of approximately 20 mg KOH/g is required for sufficient stabilization of the emulsion, at least 14.6% fatty acids (alkyd resin standards) shall be used. Water-reducible, air-dried alkyd resins typically contain fatty acids.
Since it contains 30-40%, the above amount is about half of the fatty acids present. This fatty acid component appears to be lost due to film crosslinking. This is because double bonds that are not blocked by adduct formation are lost by dimerization during the preparation of the intermediate due to the high reaction temperatures. This explains the relatively poor drying properties of the products produced according to DE 24 16 658. At present, there are no products that are fully satisfactory with respect to any of the essential properties, namely storage stability and drying rate. Furthermore, the use of the products produced according to European Patent No. 0002488 is severely limited due to the content of phenolic resols and highly unsaturated oils. The product is dark in color and has a strong tendency to yellow. Therefore, it cannot be formulated for brightly colored finishes. Its use is limited to primers, fillers and colored industrial enamels. Therefore, if, on the one hand, PEG is introduced into the alkyd resin in the form of a specific etherification product, and on the other hand, the carboxyl group is introduced in the form of an acidic copolymer, a general-purpose water resin with good overall performance can be used. It has been found that emulsifiable alkyd resins can be obtained. Accordingly, the present invention provides a method for producing improved aqueous emulsions for air-drying and baking coatings based on alkyd resins modified with polyethylene glycol, comprising: 1 mole of polyethylene glycol from 500 to 5000 and the general formula (wherein, a reaction product obtained from 1.7 to 2.1 moles of a 1,2 epoxy compound of (b) the reaction product of an epoxidized glyceride oil with an epoxy content of 4 to 9% and a monoalkoxyethylene glycol with a molecular weight of 500 to 3000 in an amount of 0.8 to 0.95 mol based on its available oxirane groups; It is reacted with polyols, fatty acids and/or fats and oils, and aromatic monocarboxylic acids and/or dicarboxylic acids as necessary by transesterification, and the acid value is 15 or less, preferably 5 mgKOH/g, and the hydroxyl value is 50 to 50.
250mgKOH/g and an alkyd resin intermediate having a polyethylene glycol moiety of 3.3 to 15% by weight, (c) 50 to 90% by weight of this alkyd resin intermediate, 6 to 40% by weight of methacrylic acid, and an iodine value of 6 to 40% by weight. is at least 125 unsaturated fatty acids
Copolymers 10 to 55% by weight and 20 to 70% by weight of one or more vinyl and/or vinylidene compounds having no other functional groups besides double bonds
50% by weight and an acid value of 10 at 170 to 200°C.
from 35 mg KOH/g, and from 6 to 15 ml/g, and an intrinsic viscosity (chloroform, 20°C) from 6 to 15 ml/g, and
esterification until a PEG content of 3 to 8% is obtained; (d) the carboxyl groups of the modified alkyd resin thus obtained are neutralized with ammonia or amines and emulsified in water by adding up to 20% by weight of an organic co-solvent. The present invention relates to a method characterized by the following. According to the present invention, it is possible to produce an alkyd resin emulsion that is ideal as a top quality air-drying and baking paint. In particular, they exhibit excellent storage stability over long periods of time and over a wider than mild temperature range. Furthermore they meet every demand regarding drying power and film performance. The excellent performance of the emulsions of the invention is due to the well-designed molecular structure, the essential feature being the possible resistance to hydrolysis of the incorporated stabilizing hydrophilic groups. Component (a) can be constituted in a variety of ways. Compounds of the above-mentioned general formula are obtained by epoxidation of esters of monohydric alcohols and monounsaturated fatty acids. Specific examples are lauroleic acid, myristoleic acid, palmitoleic acid, oleic acid or erucic acid. Epoxidation products of esters of oleic acid are particularly suitable. The alcohol component is a monovalent saturated aliphatic having 1 to 10 carbon atoms,
Cycloaliphatic and aromatic alcohols. Epoxidation is carried out in a known manner, namely with hydrogen peroxide and formic acid. The products according to the general formula must contain one 1,2-epoxy group per molecule and be present in technical mixtures with a concentration of at least 75%. Products of this type are commercially available and are specified in the data sheets as n-alkyl- or i-alkyl epoxy fatty acid esters. The average molecular weight of suitable polyethylene glycol is
500-5000. In the presence of a catalyst, they are 1:
It is reacted with an epoxy compound by etherification in a molar ratio of 1.7 to 1:2.1. Ideally, this reaction would attach fatty acid esters to both sides of the PEG molecule through ether bonds. PEG in industrial methods
water is removed by vacuum distillation with the help of an entraining agent,
Add catalyst and heat to 100-150°C. The epoxy compound is then added over several hours and maintained at that temperature until the epoxy number is below 0.02, preferably 0.01. Suitable catalysts are, for example, sulfuric acid, perchloric acid, aluminum chloride and boron trifluoride and its etherates. The etherified product thus obtained (polyethylene glycol diether) is then desorbed from the monohydric alcohol from the initially used monoepoxy compound in the presence of a suitable solution such as Lissage or calcium hydroxide at about 250°C. , with compounds commonly used in the production of alkyd resins, such as polyols, fatty acids and/or oils, and optionally with some aromatic monocarboxylic and/or dicarboxylic acids by transesterification. The alcohol liberated from the intermediate product is quantitatively removed by distillation. The remainder of the dicarboxylic acid is then added, if necessary, along with further polyols and/or fatty acids to reduce the acid value of the alkyd resin intermediate prepared by known methods to below 15 mgKOH/g, preferably below 5 mgKOH/g, and Esterify until an intrinsic viscosity of 4-10 ml/g (chloroform, 20° C.) is obtained. Raw materials for alkyd resins are well known to those skilled in the art, so a detailed enumeration will not be given here. Another manufacturing method is to first mix all other ingredients except the PEG-modified fatty acid ester with an acid value of 15 mg.
It is also possible to process the alkyd resin into an alkyd resin having KOH/g or less and then incorporate polyethylene glycol diether into this alkyd resin by transesterification. Instead of the alkyd resins, fatty acid esters of epoxy resins of the bisphenol A type or fatty acid esters of styrene-allylic alcohol copolymers can be used. Suitably the alkyd fatty intermediates have a fatty acid content of 1 to 60, including those from epoxy compounds.
%, and a hydroxyl value of 50 to 250 mgKOH/g. The PEG content of the product lies between 3.3 and 15%. Instead of homogeneous alkyd resin intermediates, mixtures with PEG-free components can also be used, if desired. In the final product there is an alkyl chain containing at least 7 carbon atoms between the PEG chain and the ester bond. Therefore, PEG by hydrolysis
separation is substantially prevented. The involvement of secondary hydroxyl groups generated during the etherification reaction of PEG and epoxy groups in re-esterification and esterification during the preparation of alkyd intermediates is excluded due to steric hindrance of excess primary hydroxyl groups. be able to. Another type (aa) of component (a) is obtained by reacting an epoxidized glyceride oil having an epoxy oxygen content of 4 to 9% with 0.8 to 0.95 mol of monoalkoxypolyethylene glycol per mole of oxirane groups of the epoxidized oil. can get. The average molecular weight of this polyglycol group is preferably 500 to 3,000. The epoxidized glyceride oil used according to the invention is a commercial product obtained by epoxidation of drying oils, in particular soybean oil, with an iodine number of 100 to 180, with peracids. Other epoxidized oils are obtained from linseed oil, sunflower oil, cottonseed oil, etc. The epoxy oxygen content of these oils ranges from 4 to 9%. As monoalkoxypolyethylene glycol (APG) products with an average molecular weight of 500 to 30,000 are used. The alkoxy group is 1-
One having 4 carbon atoms is preferable. A slight excess of epoxy groups is used according to the invention in order to bind the APG as quantitatively as possible. per mole of oxirane group for the present invention.
A molar proportion of APG of 0.8 to 0.95 has been found to be advantageous. In this case it has been found to be advantageous to use APG rather than polyethylene glycol due to the high functionality of the epoxidized oil. The reaction is carried out according to the methods cited on pages 16-17 and 26-34. Look at the reaction in terms of epoxy value.
Continue the reaction until a conversion of at least 95% of the hydroxy groups of APG is achieved. The secondary hydroxyl group formed when the oxirane group opens is considered not to actually react due to steric hindrance. Further processing of the APG-ether is carried out according to the method described for the PEG ether. APG
The complete incorporation of the ether is in any case
Achieved with a reaction time of 90 minutes maintaining a reaction temperature of 240-250°C. The amount of APG ether is also chosen such that the polyethylene glycol content corresponds to a portion of 3.3 to 15% of the alkyd resin intermediate. In connection with the possibilities of component (a) by this modification, the range of commercially available and economical raw materials used is substantially widened without adversely affecting the observed stability of the final product. According to the invention, for the introduction of carboxy groups necessary for the stabilization of the emulsion, 6 to 40% by weight of methacrylic acid, a dry fatty acid with an iodine value of at least 125;
Use of polymers obtained by free radical polymerization of 20-55% by weight and 20-70% of vinyl and/or vinylidene compounds, especially one of the compounds of acrylic acid, which have no reactive groups other than double bonds. do. Suitable drying fatty acids for the preparation of these intermediates are those with conjugated double bonds, such as dehydrated castor oil fatty acids or isomerized fatty acids, or isolated double bonds, such as technical soybean oil, safrole or linseed oil fatty acids. It has double bonds. Fatty acids with isolated unsaturated bonds must be used in excess due to their weak reactivity. If the fatty acid is not completely reacted during polymerization, its remainder is incorporated into the alkyd resin intermediate during esterification. The highest possible polymerization yield must be aimed at. Suitable vinyl and vinylidene compounds are styrene, vinyltoluene, or vinyl esters of acetic, propionic or Versatic acids. Commercially available esters of acrylic or methacrylic acid are preferred. The selection is made according to, inter alia, compatibility with the alkyd resin intermediate. Usually the polymer with the best compatibility also exhibits the best emulsifying effect. Polymerization is carried out at 80-140°C, preferably 90-110°C. All suitable initiators are compounds that generate and separate radicals at this temperature. Dibenzoyl peroxide is a preferred initiator. Polymerization chain transfer agents such as tert-dodecyl mercaptan are used to limit the molecular weight. The end point of the polymerization is considered to have been reached when the amount of non-volatile residue becomes constant, ie when the volatile monomer has substantially disappeared from the reaction mixture. Under the conditions cited, side reactions such as dimerization of fatty acids are substantially suppressed. The uncopolymerized fatty acids thus remain unchanged and their oxidative crosslinking ability is retained until after their introduction into the alkyd resin intermediate. The carboxy group of methacrylic acid exhibits a tertiary structure after the polymerization reaction, and therefore its reactivity decreases. Therefore, in the reaction between the alkyd resin and the polymer resin, they remain substantially unchanged and serve to stabilize the emulsion after neutralization. In the final product, the presence of a long chain hydrophobic alkyl of the fatty acid between the stabilizing carboxylate group and the ester bridge strongly prevents hydrolytic cleavage. The introduction of vinyl compounds and acrylates serves to adjust the compatibility range and amphipatic properties of the polymer. On the one hand, this results in easier incorporation of the polymer by adjusting the compatibility with the alkyd component, and on the other hand, an emulsifying effect is obtained even if the polymer is not fully incorporated or is subsequently separated off. After complete esterification of the fatty acid carboxy groups of the polymer, the alkyd resin intermediate and polymer are
Acid value 10-35, preferably 12-25 mgKOH/g and intrinsic viscosity 6-15 mgKOH/g (chloroform,
Combine at 170-200°C to 20°C. The PEG content of the final product is preferably in the range 3-8%. The resin should contain up to 20% organic co-solvent, preferably 5-15
% and emulsify at a temperature of 40 to 80 °C in water containing a sufficient amount of ammonia or organic amine to neutralize 50 to 100% of the carboxyl groups of the resin.
Suitable auxiliary solvents are primarily alcohols or ether alcohols, such as n-butanol or ethylene glycol butyl ether. Suitable amines are, for example, triethylamine or dimethylethanolamine. Emulsions prepared in accordance with the present invention are useful as bases for air-dried and baked paints, as shown in the examples, and are applied by any conventional method. In the preparation of baking paints, water-compatible amine-formaldehyde resins are added as crosslinking agents. A "water-dispersible epoxy-modified alkyd resin" is known from DE 2809840.
According to the type of epoxy compound (aromatic compound with at least two epoxy groups per molecule) and the method of preparation (introduced by direct esterification with PEG), the above specifications are not relevant to the present invention. The following examples illustrate the method of the invention. All parts or percentages are by weight unless otherwise specified. The stated values of intrinsic viscosity are determined at 20°C in chloroform. () Production of polyethylene glycol-diether (component a) Polyethylene glycol-diether (PGDA¨) is produced according to the composition listed in the table by the following method. Toluene 10% is added to remove water from the polyethylene glycol and the mixture is heated to 120° C. and kept under vacuum until distillation is complete. The temperature is then lowered to 110° C. and the BF ₃ complex is added. Next, epoxy fatty acid ester was added continuously over 2 hours until the epoxy value decreased to 0.01 or less.
Maintain temperature at 110°C.

[Table] () APG - Production of ether (APG¨A) (components
aa) Prepare APGA¨ according to the composition listed in Table 2 in the following manner. 10% toluene to desorb water from APG
is added and the mixture is heated to 120° C. and maintained at this temperature under vacuum until the end of distillation. Then the temperature
Lower to 110 °C and add BF ₃ complex. Epoxidized glyceride oil was then added continuously over a period of 5 hours, and the temperature was increased until at least 95% conversion of the hydroxyl groups of APG was observed according to the epoxy value.
Maintain at 110°C.

[Table] () Production of alkyd resin intermediate The properties of the alkyd resin intermediate are listed in Table 3. Alkyd resin intermediate A1: 110 g of pentaerythritol, 150 g of PGDA, 120 g of p-tert-butylbenzoic acid, 60 g of phthalic anhydride, 20 g of linseed oil fatty acid, 0.8 g of zinc octoate (zinc 8%)
g and 0.8 g of calcium octoate (4% calcium) are heated to 250° C. within 4 hours and maintained at this temperature for 1 hour. At this stage, 5 g of water-insoluble liquid is distilled out in addition to distilled water. Drain and discard all distillate. Next, lower the temperature to 200℃.
Then 70 g of dehydrated castor oil fatty acid and 36 g of phthalic anhydride are added. Next, the temperature was raised to 200℃ again and the acid value was 3 mg by azeotropic circulation of xylene.
Esterify to below KOH/g. Discharge the resin without diluting it. Alkyd resin intermediate A2: 165 g of tung oil, 45 g of linseed oil fatty acid, 291 g of PGDA, 185 g of pentaerythritol, 155 g of p-tert-butylbenzoic acid,
Zinc octoate (zinc 8%) 0.8g and calcium octoate (calcium 4%) 1.6
g is heated to 250° C. within 60 minutes and kept at that temperature to distill off 6 g of water-insoluble distillate. The batch is then cooled to 150 DEG C. and 130 g of hexachloroendomethylenetetrahydrophthalic acid, 80 g of tetrahydrophthalic anhydride and 0.6 g of 50% triphenyl phosphorite in xylol are added. Finally, it is esterified by azeotropic distillation with xylene at 190°C until the acid value becomes 5 mgKOH/g or less. Alkyd resin intermediate A3: PA¨G-free alkyd resin): 85 g of tung oil, 80 g of p-tert-butylbenzoic acid, 95 g of pentaerythritol, 30 g of benzoic acid and 25 g of tall oil fatty acid at 230°C.
time, pre-esterification or transesterification. Lower the temperature to 200℃ and add 80g of phthalic anhydride.
and 15 g of phenolic resol from 1 mol of p-tert-butylphenol and 2 mol of formaldehyde are added. Next, esterification is completed by azeotropic distillation at 190°C. Alkyd resin intermediate A4: Alkyd resin intermediate A1 is used to produce an alkyd resin with a higher fatty acid content. 120 g of p-tert-butylbenzoic acid is replaced by 40 g of p-tert-butylbenzoic acid and 130 g of tall oil fatty acid. The processing method is the same. Alkyd resin intermediate A5: trimethylolpropane 285g, pentaerythritol 55g, PGD
A¨3105g, coconut oil fatty acid 120g, phthalic anhydride 240g, adipic acid 55g, benzoic acid 27g and calcium octoate (calcium 4
%) 1.8 g within 3 hours to 240°C and maintain this temperature for 30 minutes. Approximately 8 g of water-insoluble distillate is distilled out at this stage. Next, the mixture is esterified by azeotropic distillation until the acid value becomes 2 mgKOH/g or less. Alkyd resin intermediate A6: Alkyd resin intermediate A6 is an esterification product of a styrene-aryl alcohol copolymer with a hydroxy content of 7.7%. 120g of this copolymer, PGDA¨
20g, calcium octoate (calcium 4
%) 0.3g and zinc octoate (zinc 8
%) 0.3g to 250°C within 3 hours and held at this temperature for 1 hour. 2 g of water-insoluble distillate are thereby produced. Next tall oil fatty acid 40
g and 13 g of p-tert-butylbenzoic acid are added and esterified by azeotropic distillation with xylol at 220° C. until the acid number is below 2 mg KOH/g. Alkyd resin intermediate A7: (Alkyd resin intermediate A7 has an epoxy equivalent of 750 as an epoxy resin.
A modified epoxy resin ester with a diepoxide based on bisphenol A having a molecular weight of ~820): A mixture of 40 g of tall oil fatty acid, 13 g of p-tert-butylbenzoic acid and 0.2 g of triethylamine is heated to 150°C. 120 g of the above-mentioned epoxy resin is added little by little over 1 hour. The temperature is raised to 180° C. and 0.3 g of calcium octoate (4% callucium), 0.3 g of zinc octoate (8% zinc) and 120 g of PGDA are added. The temperature is increased to 250° C. over 2 hours and held at that temperature for 60 minutes to distill off 2 g of water-insoluble distillate. Next, the resin is esterified by azeotropic distillation with xylol at 220°C to an acid value of 2 mgKOH/g or less. Alkyd resin intermediate A11: This resin corresponds to alkyd resin A2, and its PGD
A ¨297g is replaced with APGA ¨194g. The transesterification step at 250°C was extended to 120 minutes. Alkyd resin intermediate A12: This resin corresponds to alkyd resin intermediate A-5. However, replacing PGDA¨3105g with APGA¨281g,
The transesterification step at 240°C was extended to 120 minutes.

【table】

【table】 % %

Claims (1)

[Claims] 1. A method for producing an improved aqueous emulsion for air-drying and baking paints based on alkyd resins modified with polyethylene glycol, comprising: (a) a temperature of 100 to 150° C. in the presence of a catalyst; 1 mol of polyethylene glycol with an average molecular weight of 500 to 5000 and the general formula (wherein, X is an alkyl group having 2 to 8 carbon atoms, Y is an alkylene group having 7 to 11 carbon atoms, and Z is a saturated aliphatic, alicyclic, or aromatic carbonized A reaction product obtained from 1,7 to 2,1 moles of a 1,2 epoxy compound (which is a hydrogen group), and the epoxy value of the reaction product is 0.02 or less, or (aa) Epoxidized glyceride oil with an epoxy content of 4 to 9% and a molecular weight of 500 to 0.8 to 0.95 mol based on its available oxirane groups.
(b) in a subsequent reaction step by transesterification with polyols, fatty acids and/or oils, and optionally aromatic monocarboxylic and/or dicarboxylic acids. React, acid value is 15 or less, preferably 5 mgKOH/g, hydroxyl value is 50 to 250 mg
KOH/g and an alkyd resin intermediate having a polyethylene glycol moiety of 3.3 to 15% by weight, (c) 50 to 90% by weight of this alkyd resin intermediate, 6 to 40% by weight of methacrylic acid, and an iodine value. is at least 125 unsaturated fatty acids
Copolymers 10 to 25% by weight and 20 to 70% by weight of one or more vinyl and/or vinylidene compounds having no other functional groups besides double bonds
50% by weight and an acid value of 10 at 170 to 200°C.
(d) The modified alkyd resin thus obtained is esterified with ammonia or an amine until a polyethylene glycol content of 3 to 35 mg KOH/g and an intrinsic viscosity (chloroform, 20°C) of 6 to 15 ml/g and a polyethylene glycol content of 3 to 8% are obtained. A method characterized by neutralizing carboxyl groups, adding up to 20% by weight of an organic co-solvent, and emulsifying it in water. 2. The method according to claim 1, wherein n-alkanol or i-alkanol ester of monoepoxystearic acid is used as the epoxy compound in component (a). 3. The method according to claim 1, wherein in component (aa), the reaction of the epoxidized glyceride oil and the monoalkoxypolyethylene glycol is carried out until at least 95% of the hydroxyl groups of the monoalkoxypolyethylene glycol have reacted. 4. The method according to any one of claims 1 to 3, wherein in (c), the alkyd resin intermediate and the copolymer are reacted until the acid value becomes 12 to 35 mgKOH/g. 5. The method according to any one of claims 1 to 4, wherein a fatty acid ester of a bisphenol-A epoxy resin or a styrene/allylic alcohol copolymer is used as an alkyd resin intermediate. 6. A method according to any of claims 1 to 5, wherein component (a) or (aa) is incorporated into a preformed alkyd resin intermediate by transesterification.