Stable aqueous epoxy resin dispersion, process for its preparation and its use.

It is known to produce resins by the emulsion polymerization and to produce stable aqueous dispersions of these resins, characterized in that one gives the solid resin and a suitable dispersing agent with stirring in water. In condensates such as epoxy resins, which are difficult to prepare by emulsion condensation, but must be prepared by aqueous dispersions by dispersing the solid resin in water. Such dispersions are generally quite unstable and settle already within a short time. In general they show even poorer film-forming properties. These drawbacks, namely low stability of the dispersion and poor film properties, are mainly caused by the high particle size of the resin.

The preparation of coating compositions based on polyepoxide dispersions is disclosed in US Patent No. 3,772,228, which is a heat-curing one-component coating composition is produced by mixing a solid, brittle polyepoxide, a solid brittle epoxy hardeners, eg a polyanhydride, and optionally one Epoxidhärtungsbeschleuniger in a liquid which is not a solvent for the various components, grinding the mixture and dispersed. Aliphatic hydrocarbons are preferred. Obtained in this manner epoxy resin dispersions, however, are non-aqueous and bring the use of hydrocarbon solvents inherent dangers.

The preparation of stable aqueous, free of organic solvents, dispersions of epoxy resins relatively low molecular weight (200-4000, preferably 240-1300) with average particle sizes of less than about 10 microns with the use of anionic, nonionic, but preferably cation-active dispersants is also well known (US-A-3879324). Here, the epoxy resin is heated until molten, mixed with water and the dispersant and then passed through a colloid mill. As such epoxy resins with the specified molecular weight below 100 ° C, the boiling point of water, melt can be dispersed by this method. This sharp restriction has the disadvantage that it excludes numerous useful epoxy resin of high molecular weight. Besides, the dispersion still delivers at the boiling point of water, relatively large particles that settle quickly.

It has also been described the preparation of Epoxidfestharzen (US Patent 4,122,067), which can be obtained directly in the form of an aqueous dispersion. In this case, block polymers of ethylene oxide and polypropylene glycol, or polymers of polyethylene glycols having a molecular weight from 2000 to 20000 and polyglycidyl ethers of polyphenols having a molecular weight from 300 to 2000 in a molar ratio of 2 as a dispersing agent: 1 to 6: 5. Also by this method are obtained only dispersions with a particle size of 1 to 3 micrometers.

According to EP-B-0081163 polyalkylene glycol derivatives are used as non-ionic dispersing agents for stable aqueous epoxy resin dispersions, wherein average particle sizes of less than 1 .mu.m are possible. However, the coatings obtainable with these dispersions satisfy not yet in a number of properties.

According to EP-A-0,051,483 epoxy resin dispersions are obtained from self-emulsifying epoxy resins, the glycidyl ether of polyoxyalkylene glycol and optionally also contain a monoepoxide as reactive diluent. The maximum particle size of about 3 microns are given. Films prepared from these dispersions and hardeners have by the content of polyoxyalkylene glycol glycidyl ethers, which are very inert, and optionally monoepoxides which act as chain terminators, a relatively soft surface.

According to US-A-4,399,242, the epoxy resin is reacted at about 120 ° C with a diisocyanate before it is mixed with a diglycidyl ether as emulsifier einzubauendem a block polymer of ethylene oxide and propylene oxide, and dispersed with water. The size of the dispersed particles is also in the order of 1 to 3 microns. The film formation is unsatisfactory.

In the older EP-A-0272595 an aqueous dispersion has been proposed on the basis of a special self-emulsifying epoxy resin, good storage stability with a simultaneously low content of organic solvents and results in coatings having good surface properties. However, under certain conditions, these dispersion tends to form a skin.

The invention now relates to an aqueous dispersion based on a self-emulsifying epoxy resin A), the dispersion in addition to water B), optionally up to 15 wt .-%, based on the total dispersion, organic solvents C) and optionally usual additives D), wherein the self-emulsifying epoxy resin a) has an epoxy equivalent from 250 to 10,000 and is a condensation product is from<ul><li>a) 50 to 80, preferably 55 to 70 wt .-% of an epoxy compound having at least two epoxide groups per molecule and an epoxide equivalent weight of 100 to 2000</li><li>b) 35 to 17, preferably 35 to 20 wt .-% of an aromatic polyol and </li><li>c) 15 to 3, preferably 9-4 wt .-% of a condensation product of an aliphatic polyol having an average molecular weight (Mw) from 200 to 20,000, an epoxy compound having at least two epoxide groups per molecule and an epoxide equivalent weight of 100 to 2000 and from a mono- and / or polyisocyanate, wherein the equivalent ratio of the OH groups to the epoxy groups being 1: 0.85 to 1: 3.5, the amount of mono- and / or polyisocyanate 0.05 to 5 wt .-%, based on the amount of aliphatic polyol and epoxy compound, and the epoxy equivalent weight of this condensation product is at least 200th</li></ul>

The invention further relates to a method for preparing these epoxy resin dispersions, characterized in that first the self-emulsifying epoxy resin A) by condensation of the three components A (a), A (b) and A (c) at elevated temperatures in the presence of a condensation catalyst and optionally of organic solvents C) is prepared, then optionally further organic solvents C) are added, and are then added to the so obtained solution at 30 to 100 ° C corresponding amounts of water and, if appropriate, the compounds corresponding to D) with vigorous stirring.

Finally, the invention also the use of these epoxy resin dispersions for preparing coating materials, coatings, molding compounds and curable compositions of the subject.

The self-emulsifying epoxy resin according to A) the dispersion of the invention preferably has an epoxy equivalent weight from 350 to 2500, especially from 450 to 1500. The average particle size of the dispersed resin is not higher than 1.0 micron and usually is preferably 0.3 to 1 , 0 microns and more preferably 0.3 to 0.8 microns. The portion of this resin in the total dispersion is generally about 20 to 70 wt .-%, preferably about 25 to 55 wt .-%.

The 1,2-epoxy compounds according to Aa) and Ac), is with polyepoxides on average at least two epoxide groups per molecule. These epoxy compounds may be both saturated and unsaturated aliphatic, cycloaliphatic, aromatic or heterocyclic and can contain hydroxyl groups. They may also contain substituents which under the mixing or reaction conditions no interfering side reactions, for example alkyl or aryl substituents, ether groups and the like.

Preferably, these epoxy compounds are polyglycidyl ethers based on polyhydric, preferably dihydric alcohols, phenols, hydrogenation products of these phenols and / or novolaks (reaction products of mono- or polyhydric phenols with aldehydes, especially formaldehyde, in the presence of acidic catalysts). The epoxide of these epoxy compounds are preferably between 160 and 500, in particular between 170 and 250. be mentioned, for example, polyhydric phenols: resorcinol, hydroquinone, 2,2-bis (4-hydroxyphenyl) propane (bisphenol A), isomer mixtures of dihydroxydiphenylmethane (bisphenol F), tetrabromobisphenol A, 4,4'-Dihydroxydiphenylcyclohexan, 4,4'-dihydroxy-3,3'-dimethyldiphenylpropane, 4,4'-dihydroxydiphenyl, 4,4'-Dihydroxybenzophenol, bis (4-hydroxyphenyl) -1,1-ethane, bis (4-hydroxyphenyl) -1,1-isobutane, bis (4-hydroxy-tert-butylphenyl) -2,2-propane, bis (2-hydroxynaphthyl) methane, 1,5-dihydroxynaphthalene, tris (4-hydroxyphenyl) methane, bis (4-hydroxyphenyl) ether, bis (4-hydroxyphenyl) sulfone etc. and the chlorination and bromination products of the above-mentioned compounds. Bisphenol A is particularly preferred.

The polyglycidyl ethers of polyhydric alcohols are suitable. Examples of such polyhydric alcohols ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, polyoxypropylene glycols are (n = 1-10), 1,3-propylene glycol, 1,4-butylene glycol, 1,5-pentanediol, 1,6-hexanediol , 1,2,6-hexanetriol, glycerol and bis (4-hydroxycyclohexyl) -2,2-propane mentioned.

It can also be used polyglycidyl esters of polycarboxylic acids which are dimerized by the reaction of epichlorohydrin or similar epoxy compounds with an aliphatic, cycloaliphatic or aromatic polycarboxylic acid such as oxalic acid, succinic acid, adipic acid, glutaric acid, phthalic acid, terephthalic acid, hexahydrophthalic acid, 2,6-naphthalenedicarboxylic acid and linolenic acid. Examples are adipic acid, phthalic acid and hexahydrophthalic.

A detailed list of suitable epoxide compounds can be found in the manual "epoxy compounds and epoxy resins" by AM Paquin, Springer Verlag, Berlin 1958, Chapter IV, and in Lee, Neville "Handbook of Epoxy Resins", 1967, Chapter 2. Mixtures of several epoxy compounds are used.

Aromatic polyols corresponding to A (b), preferably the OH-containing aromatic compounds containing rings in question as described above for components A (a) and A (c), so for example, polyhydric, preferably dihydric phenols, their chlorination, bromination and / or novolaks. Preferably, the OH groups are bonded directly to the aromatic ring. here is particularly preferably bisphenol A.

The aliphatic polyols of component Ac) are preferably polyether polyols (polyalkylene glycols) having average molecular weights (<o>M</o>w; gel permeation chromatography; Polystyrene standard) of preferably 600 to 12000, particularly 2000 to 8000 and OH numbers advantageously from 10 to 200, preferably from 15 to 60. These polyether polyols preferably have only terminal, primary OH groups. For example, block copolymers of ethylene oxide and propylene oxide herein and polyethylene, polypropylene and polybutylene may be mentioned, wherein mixtures of the respective polyalkylene glycols may be used. Polyethylene glycols are preferably used.

wherein said condensation product Ac) is preferably the equivalent ratio of the OH groups to the epoxy groups is either c₁) 1: 0.85 to 1: 1.5, in particular 1: 0,95 to 1: 1,20 and the epoxy equivalent weight of at least 100,000, preferably 100,000 to 400,000 or c₂) the equivalent ratio is 1: 1.8 to 1: 3.5, particularly 1: 2.0 to 1: 2.6 and the epoxide equivalent weight from 400 to 10,000.

This condensation product A (c) can for example by condensation of the above polyether polyols c₁ with the polyglycidyl ethers in the presence of, for example, the following specific catalysts) at elevated temperature, generally from 50 to 200, preferably 90 to 150 ° C, are obtained: Boron trifluoride and its complexes, for example with water, phosphoric acid, acetic acid (1: 1 and 1: 2), methanol, diethyl ether, tetrahydrofuran, phenol, tricresyl phosphate, ethylene glycol monoethyl ether, polyethylene glycol (MW 200), dimethyl sulfoxide, di-n-butyl ether, di- n-hexyl ether and succinic acid, or tetrafluoroboric in aqueous or organic solution. but are also suitable Lewis acids on the other base, as SnCl₄. Preferably used by these catalysts BF₃-diethyl ether, BF₃-acetic acid and tetrafluoroboric. The amount of catalyst is generally 0.1 to 5, preferably 0.15 to 1 wt .-%, based on the reaction mixture. In order to better dosing the catalyst can in a solvent such as diethyl ether, a glycol ether or cyclic ethers, ketones or the like, preferably dioxane or methyl isobutyl ketone up to 0.5 to 20, preferably be diluted from 2.5 to 12.5 wt .-%.

The two components are employed in such quantities that the equivalent ratio of OH groups to epoxide groups in allgeminen 1: 0.85 to 1: 1.5, preferably 1: 0.95 to 1: 1.20 is.

Preferred condensation products (dispersant) A (c) are those of the epoxy compounds described above, particularly polyglycidyl ethers of bisphenols, with aliphatic polyols, the epoxide equivalent weight of these condensation products c₁ with the use of the catalysts) of at least 50,000, preferably at least 100 000 and in particular between 100 000 and 400 000, is located.

If one uses as specific catalysts BF₃ in the form of stable complexes (→ c₂), for example complexed with amines, used to prepare the condensation products A (c), the two components advantageously used such quantities that the equivalent ratio of OH groups to epoxy groups is 1: 1 , 8 to 1: 3.5, preferably 1: 2.0 to 1: 2.6 is. Suitable catalysts for this procedure are BF₃-amine complexes which are soluble in the reaction mixture and in which the forming the complex amine has a pK_bValue has in aqueous solution of 15 to 4.5. Suitable BF₃-amine complexes, for example those derived from the following amines (pK_bValues ​​are formed in parentheses) and BF₃: n-amyl amine (10.63), aniline (4.63), β-phenylalanine = 2-aminoethyl benzene (9.84), 2-ethylbenzimidazole (6.18), benzylamine ( 9.33), tans-bornylamine (10,17), 1-amino-3-methyl butane (10.60), 1,4-diaminobutane (11.15), n-butylamine (10.77), t-butylamine (10.83), n-butylcyclohexylamine (11,23), cyclohexylamine (10.66), n-decylamine (10,64), diethylamine (10.49), diisobutylamine (10.91), diisopropylamine (10.96 ), dimethylamine (10.73), n-dodecanamine = laurylamine (10.63), 2-aminoethanol (9.50) ethylamine (10.81), Hexadecanamin (10,63), 1-Aminohepten (10.66) , 2-aminoheptane (10.88), n-hexylamine (10.56), 2,4-dimethylimidazole (8.36), morpholine (8.33), methylamine (10.66), n-nonylamine (10, 64) Octadecanamin (10,60), octylamine (10.65), 3-aminopentane (10,59), 3-amino-3-methylpentane (11.01), n-pentadecylamine (10.61), piperazine ( 9.83), propylamine (10.71), pyrrolidine (11.27), myristylamine Tetradecanamin = (10,62), Tridecanamin (10,63), triethylamine (11,01), trimethylamine (9.81).

BF₃-benzylamine, BF₃-monoethylamine, BF₃ and BF₃-propylamine-n-butylamine are preferred. Highly suitable are also by modifying in a liquid form brought BF₃ amine complexes, such as those from the company Anchor Chemical Ltd. (Manchester) under the name "Anchor" in 1040 (15-16% BF₃ containing) or "Anchor" 1171 (11-12% BF₃ containing) are placed on the market.

The reaction of the hydroxyl groups with the epoxy groups may be carried out in the temperature range of 20 to 200 ° C. The reaction temperature depends on the respective BF₃-amine complex. For example, the reaction temperature is using BF₃-monoethylamine or BF₃-benzylamine at 130 to 140 ° C, with the use of liquefied amine complex to 170 ° C. therefore it is heated suitably, the reacted mixtures of hydroxyl groups and epoxide-containing compounds up to the temperature at which the reaction at a sufficient rate, that is, in 30 minutes to 5 hours, expires. The reaction is advantageously monitored by the increase in the epoxide equivalent, which indicates a reduction of the epoxide groups. The reaction can be stopped by cooling below the reaction temperature. A part of the BF₃-amine complex is consumed during the reaction by incorporation of fluoride ions into the reaction product. Any excess of BF₃-amine complex can be rendered harmless in excess of the complex according to reaction sequence by the addition of basically acting substances, such as bleaching earth, calcium oxide, calcium hydroxide, barium oxide and barium hydroxide. The basic acting substances are removed along with the arising from them and the BF₃-amine complexes products by filtration.

The amount of these catalysts, C₂) is in general likewise 0.1 to 5, preferably 0.15 to 1 wt .-%, based on the reaction mixture. In order to better dosing the catalyst can in a suitable solvent up to 0.5 to 10, preferably be diluted from 2.5 to 12.5 wt .-%.

Preferred condensation products (dispersant) A (c) using the catalysts c₂) are those of the epoxy compounds described above, particularly polyglycidyl ethers of bisphenols, with aliphatic polyols, the epoxide equivalent weight of these condensation products 200 to 120,000, preferably 400 to 10,000, is ,

When monoisocyanates for preparing component Ac) for example, those in question, which have only one isocyanate group of home, such as methyl, ethyl isocyanate, the Propylisocyanate that Butylisocyanate, n-dodecyl, phenyl, α-naphthyl udgl. Moreover, here also partially blocked, to name one free NCO group-containing polyisocyanates. Polyisocyanates, the compounds mentioned below are suitable. In the capping agents are preferably aliphatic, cycloaliphatic or alkylaromatic monohydric alcohols, for example lower aliphatic alcohols such as methyl, ethyl, the various propyl, butyl and hexyl alcohols, heptyl, octyl, nonyl, decyl, dodecyl and the like; Methoxy (1- or 2-) propanol; and also unsaturated alcohols such as allyl alcohol and Propargolalkohol, cycloaliphatic alcohols such as cyclopentanol, cyclohexanol, alkyl aromatic alcohols such as benzyl alcohol, methyl and p-methoxy and p-nitrobenzyl alcohol and monoethers of glycols such as ethylene glycol monomethyl ether, -monoethyläther monobutyl ether or the corresponding monoether of propylene glycol. Preference is given here ethylene glycol, 2-ethylhexanol, butyl diglycol, butyl glycol and benzyl alcohol and in particular the alcohols, form the liquid Halburethane.

As poly-, preferably diisocyanates, the usual, well known in the polyurethane or paint field polyisocyanates can be used, for example, aliphatic, cycloaliphatic or aromatic polyisocyanates. Typical examples of such polyisocyanates are: Toluylendiisocyanat- (2.4) as well as mixtures thereof with Toluylendiisocyanat- (2.6), Toluylendiisocyanat- (2.6), diphenylmethane (4.4 '), 1,6-hexamethylene diisocyanate, Naphthylendiisocyanat- (1.5) , m-xylylene diisocyanate, 1-methyl-2,4-diisocyanato-cyclohexane, isophorone diisocyanate, 2,4,4-trimethyl-1,6-diisocyanatohexane, dimer Toluylendiisocyanat- (2.4), N, N'-di- ( 4-methyl-3-isocyanatophenyl) urea, N, N ', N˝Tri- (6-isocyanato-hexyl) biuret, Triphenylmethantriisocyanat- (4,4'4˝), the reaction product of 3 moles of toluene diisocyanate (2, 4) and 1 mole of 1,1,1-trimethylolpropane, tri-, and polymerization products of Toluylendiisocyanat- (2,4), and copolymerization products of Mischtrimerisations- Toluylendiisocyanat- (2,4) and 1,6-hexamethylene diisocyanate, mixtures of isomeric diphenylmethane diisocyanates, more two each on methane groups linked benzene nuclei containing polyisocyanates and diisocyanates with diphenylmethane structure whose isocyanate groups are partially converted to carbodiimide.

Isocyanates are preferred phenyl isocyanate, the isomers and mixtures of toluene diisocyanate, isophorone diisocyanate and the isomers or their mixtures of Trimethylhexamethylendiisocyanats used.

The reaction with the isocyanates mentioned may in the temperature range from 50 to 140 ° C, preferably 110 to 135 ° C in a period of 15 to 400 min., Preferably 30 to 60 minutes, optionally in the presence of isocyanate inert solvents and success of catalysts , With poly (di) isocyanates this is by choosing suitable reaction conditions, in particular the quantitative ratios, to ensure that no gelling occurs.

Opposite isocyanate inert solvents that are optionally removed after the reaction by distillation, for example, esters such as ethyl acetate, butyl acetate, methyl glycol acetate and ethyl glycol acetate, ketones such as methyl ethyl ketone, methyl isobutyl ketone, aromatics such as toluene, xylene, and higher aromatics and mixtures of the solvents mentioned. Preferably toluene or xylene are.

In the above-mentioned catalysts is customary in isocyanate chemistry, such as tert. Amines and / or compounds of di- and tetravalent tin such as diazabicyclooctane (DABCO), tin (II) octoate, dibutyltin oxide, dibutyltin dilaurate, among others, is preferred here dibutyltindilaurate.

The amount of isocyanate is from 0.05 to 5 wt .-%, preferably 0.1 to 2.5 wt .-% and in particular 0.1 to 1.0 wt .-%, based on aliphatic polyol and epoxy compound in Ac). In the presence of catalysts and isocyanates when using poly (di) while lesser amounts can be used than when working without catalysts or with the use of monoisocyanates. The isocyanate reacts with the OH groups of the reaction product of aliphatic polyol and epoxy compound (which may optionally already contain OH groups) and possibly also with the epoxide groups which are still present in this reaction product. It should be noted that after the reaction with the isocyanate in Ac) a sufficient number of reactive groups (OH and / or epoxide groups) is still present, to allow reaction with Aa) and Ab).

The amount of the condensation product A (c) in the self-emulsifying epoxy resin is 3 to 15 wt .-%, preferably 4-9 wt .-%, based on the self-emulsifying epoxy resin.

The amount of water in the dispersion of the invention is conveniently carried out at about 30 to 55 wt .-%, preferably about 35 to 50 wt .-%, based on the total dispersion.

As organic solvents, according to the component C) of the dispersion of the invention in particular ethylene glycol mono- or diethers, propylene glycol mono- or diethers, mono- or diethers of monoalcohols come with an optionally branched alkyl group of 1 to 6 carbon atoms, aliphatic alcohols with optionally branched alkyl radicals of 1 to 12 carbon atoms, araliphatic and cycloaliphatic alcohols such as benzyl alcohol or cyclohexanol, aromatics such as xylene or ketones such as methyl isobutyl ketone, it being possible also be used individually and in admixture, or these solvents. The boiling point of these solvents is preferably not above 210 ° C. Preference is given to ethylene glycol, methyl glycol, methoxypropanol, Ethoxypropanol and / or benzyl alcohol. The inventive epoxy resin dispersion preferably contains about 2 to 15, especially about 4 to 10 wt .-% of these organic solvents.

As usual additives for the purposes of D), who may be the combination of the invention may be present, here, for example, the conventional paint additives such as pigments, pigment pastes, antioxidants, leveling or thickening agents, defoamers and / or wetting agents, reactive diluents, fillers, catalysts are udgl , called. These additives, which also include hardeners and other thermosetting resins, the dispersion can be optionally added only immediately prior to processing.

As hardeners for the self-emulsifying epoxy resins of the invention, the heretofore known curing agents or hardening compounds (epoxy) are used as basic curing agents (amine curing agent), for example polyamines, Mannich bases, adducts of amines with polymers, such as polyepoxides and polyamidoamines. Furthermore, apply acidic hardeners (acid hardener) such as polycarboxylic acids and their anhydrides, and polyhydric phenols. Also, hydroxyl and / or amino-containing resins such as amine or phenolic resins are suitable for this purpose.

Examples of basic curing agents, preferably for curing at room temperature or lower temperatures (amine cold-curing agent), generally in an equivalent ratio epoxide: amine hydrogen equivalent of 1: are used (0.75 to 1.5), are polyalkylene amines such as diethylenetriamine, triethylenetetramine, tetraethylenepentamine among other things, also 2,2,4- and / or 2,4,4-trimethylhexamethylenediamine, bis- (3-aminopropyl) methylamine, 1,4-bis (3-aminopropyl) piperazine, N, N-bis (3-aminopropyl) ethylenediamine and also cycloaliphatic amines such as 1,2- or 1,3-diaminocyclohexane, 1,4-diamino-3,6-diethylcyclohexane, 1,2-diamino-4-ethylcyclohexane, 1,4-diamino -3,6-diethylcyclohexane, 1-cyclohexyl-3,4-diaminocyclohexane, isophoronediamine, 4,4'-diaminodicyclohexylmethane, 4,4'-Diaminodicyclohexylpropan, 2,2-bis (4-aminocyclohexyl) propane, 3,3 '-dimethyl-4,4'-diaminodicyclohexylmethane, 3-amino-1-cyclohexylaminopropan, 1,3- and 1,4-bis (aminomethyl) cyclohexane.

As araliphatic amines, in particular those amines are employed in which the amino groups are at rest aliphatsche available, for example, m- and p-xylylenediamine or their hydrogenation products. The amines may be used alone or as mixtures.

Suitable Mannich bases are prepared by condensation of polyamines, preferably diethylenetriamine, triethylenetetramine, isophoronediamine, 2,2,4- and 2,4,4-trimethylhexamethylenediamine, 1,3- and 1,4-bis (aminomethyl) cyclohexane, in particular m - and p-xylylenediamine with aldehydes, preferably formaldehyde, and mono- or polyhydric phenols with at least one aldehyde-reactive core site, for example the various cresols and xylenols, p-tert-butylphenol, resorcinol, 4,4'-dihydroxydiphenylmethane, 4,4'- dihydroxydiphenyl-2,2-propane, but preferably prepared phenol.

As the amine-epoxy adducts are, for example, reaction products of diamines such as ethylene diamine, propylene diamine, hexamethylene diamine, 2,2,4, 2,4,4-trimethylhexamethylenediamine, m-xylylenediamine and / or bis (aminomethyl) cyclohexane with terminal epoxides, such as propylene oxide, hexene oxide or with glycidyl ethers such as phenyl glycidyl ether, ethylhexyl glycidyl ether, butyl glycidyl ether or with glycidyl esters, such as "Cardura e", or polyglycidyl ethers or esters, such as described in Aa), or Ac), into consideration.

Polyamidoamines, which may be used for present purposes are obtained, for example by reaction of polyamines with polycarboxylic acids such as dimerized fatty acids.

Preferred amine curing agent in addition to the above polyamines, the water-soluble polyoxypropylene having molecular weights of 190-2000 and the slightly water-dispersible curing agents, such as are described in DE-A-23 32 177 and EP-B-0000605, eg modified amine adducts used. To complete the curing, the coatings obtainable from these dispersions may be heated to 50 to 120 ° C and 30 to 120 minutes.

As the acidic curing agent, usually in the ratio of equivalents epoxide: carboxyl equivalent of 1: (0.75 to 1.5) used are water-soluble polycarboxylic acids, such as cyclopentane tetracarboxylic acid, in particular butane tetracarboxylic acids such as cyclobutane tetracarboxylic acid are suitable, preferably 1, 2, 3, 4 butane tetracarboxylic acid, further, aconitic acid, citric acid or, if appropriate, anhydrides or acid esters of these acids with polyhydric alcohols having 2 to 12, preferably 2 to 6 carbon atoms, such as neopentyl glycol, glycerol, trimethylol ethane or propane, alkanediols and their oligomers, optionally one or contain more ether bridges, such as ethylene glycol, propane and butane diols, the esters always have at least 3 free COOH groups. It is also possible to use acid esters with 3 or more COOH groups of pyromellitic acid, trimellitic acid, phthalic acid, or endomethylenetetra- -hexahydrophthalsäure, maleic acid, fumaric acid or their anhydrides, where they exist, with polyhydric alcohols, for example those mentioned above, as the polycarboxylic hardener to use, provided these acidic esters possess sufficient solubility or dilutability. It should be noted that divalent carboxylic acids having at least trihydric alcohols or dihydric alcohols are reacted with at least tribasic carboxylic acids, in order to achieve a sufficient number of COOH groups in the acid ester.

Instead of or in addition to the curing agents described above can also for curing amine and / or phenolic resins find use, in amounts of from 5 to 50 wt .-%, preferably 10 to 35 wt .-%, based on the total solids content. Optionally, the dispersion is additionally added this water, so that the total solids content of 10 to 80 wt .-% is established. Examples of such amino resins are Aminaldehydharze, ie condensation products of aldehydes with melamine (melamine resins), urea (urea resins), Acetoguanamine (Acetoguanamine resins) or similar compounds or corresponding precondensates. Preferred aldehyde condensation products of melamine are especially melamine-methylol alkyl ether wherein the alkyl groups of methyl, n- or i-butyl groups, preferably consist of methyl groups, such as hexamethoxymethylmelamine, Ethoxymethoxymethylmelamin, Monomethylolpentamethoxymethylenmelamin, dimethylol-tetramethoxymethylenmelamin, Trimethyloltrimethoxymethylenmelamin and the like with a largely monomeric structure and corresponding oligomers or polymeric products.

As phenolic resin hardener may be mentioned resols, formaldehyde and phenol carboxylic acid resins and phenolic resin precursors, the commercial etherified, water-dilutable Phenolharzresole are preferred. Optionally you the phenol and / or amine resin dispersions containing acidic catalysts such as p-toluene sulfonic acid, cyclohexanesulfamic, acidic butyl phosphate and phosphoric acid - optionally also as (amine) salts - added in order to increase the speed of curing reaction, so that films generated or coatings which cure at lower temperature or in a shorter time. The amount of these acid catalysts is, for example up to 2 wt .-%, based on total solids content.

Additional curable resins within the meaning of component D) are, for example, dispersible in aqueous media resins based on Hydroxylalkylacrylestern, Hydroxyalkyden, polyesters, epoxy resins and the like. The proportion of these additional resins may be, for example, such that the total solids content of the mixture is about 10 to 80, preferably 20 to 40 wt .-% is. By adding such resins the properties of the produced from the dispersions can be influenced in a desired manner. So it is possible, for example, by the presence of the acrylate, the yellowing resistance and by the addition of alkyd resins to improve the elasticity of the coatings produced therefrom.

The total solids content of the epoxy resin dispersion of the invention may be between about 10 to 80 wt .-% are and is preferably 35 to 70 wt .-%, preferably 45 to 60 wt .-%; its viscosity is generally from 300 to 30,000 mPa · s, preferably 1000 to 7000 mPa · s (20 ° C). The epoxy resin dispersion according to the invention is characterized in particular by their good storage stability, especially due to the small average particle size of the self-epoxy resin, with low content of organic solvents. The coatings obtainable with this dispersion also have a reduced sensitivity to water, with improved hardness.

Bie the inventive method for preparing these epoxy resin dispersions, first the self-emulsifying epoxy resin A) by condensation of the three components A (a), A (b) and A (c) at elevated temperatures, generally 120 to 220 ° C, preferably 150 to 180 ° C in the presence of a condensation catalyst. Suitable as such are, for example, phosphines such as triphenyl phosphine, phosphonium salts such as, for example, benzyltrimethylphosphonium chloride, tertiary amines such as benzyldimethylamine, quaternary ammonium salts such as tetramethylammonium chloride, alkali metal hydroxides, such as NaOH, LiOH, alkali metal carbonates such as sodium carbonate, lithium carbonate, alkali salts of organic acids such as sodium formate and lithium benzoate , into consideration. In this condensation, the organic solvent C) may already be completely or partially added.

Subsequently, this resin at temperatures of 120 ° C to 220 ° C, preferably 100 to 160 ° C, the organic solvent - as long as the condensation is not already done in the presence of the total amount of the organic solvent - is added and produced a solution. Thereafter, 55 to 85 ° C is performed at temperatures of 30 to 100 ° C, preferably metered into the appropriate amount of water with vigorous stirring to form the aqueous dispersion. This dispersion is advantageously carried out using a high-speed paddle stirrer, a colloid mill, a homogenizer or another fast mixer of high shear force, for example a dissolver.

The compounds according to D (additives, hardeners, other thermosetting resins) are preferably added only immediately prior to application of the dispersion.

The dispersions of the invention are used in conjunction with suitable hardeners mainly for the production of coatings and / or intermediate coatings for a variety of applications, in particular as protective coatings on rough and porous substrates. They are further suitable for chemical- and weathering-resistant coatings and linings of objects.

Due to their favorable properties, the novel dispersions are also outstandingly suitable for one-coat. The adhering coating layer may remain unchanged, but they can also serve as Zwichenschicht, ie as a substrate for further coatings which in turn may consist of the same or another conventional coating material.

Because of their good dilutability and their other favorable properties, the dispersions of the invention are also suitable for additional use in electrodeposition.

A further possibility is its use for water-dilutable adhesives. As a binder for textile, organic and / or inorganic materials can be used. They are also suitable for use for curable molding compositions. In addition, they can also serve as an additive in plastic cements.

When used as a coating agent (or as a predominantly aqueous coating) the deposition takes place on the substrate, such as metal, wood, glass, concrete, plastic, ceramics, etc., according to conventional methods such as brushing, spraying, dipping or rolling. The coatings are provided that no curing agents are concomitantly used for the cold curing, up to about an hour cured by heating at 100 to 250 ° C for a time sufficient for curing, generally from about five minutes.

In the following experiments and examples% is in each case per cent by weight. The viscosity was always measured at room temperature using a Brookfield viscometer.

Examples

I. Preparation of the condensation products (dispersant) A (c) with a catalyst c₁)

In all examples 1 to 11 the reaction mixture was heated to 130 ° C after addition of the BF₃ connection and this temperature was maintained until the reaction had died away, recognizable by an increase in the Epoxydäquivalentgewichts to the value specified in each case.<ul><li>1) 309 g of technical grade polyethylene glycol having an average molecular weight of 4,000 and 32.5 g of a polyglycidyl ether based on bisphenol A with an epoxide equivalent weight of 185 were heated together to 100 ° C and under stirring with 0.5 ml of HBF₄, 50% H₂O, with 10 ml of methyl isobutyl ketone diluted added. The equivalent ratio OH / epoxy was 1: 1.15, the epoxy equivalent of the condensate ca. 350,000 The methyl isobutyl ketone was removed under vacuum.</li><li>2) 285 g of the condensate according to Example 1 were at 130 ° C in about 30 min. With a solution of 2.85 g toluene diisocyanate (TDI 80 = 80% 2,4-, 20% 2,6-isomer) dissolved in 10 ml of dry xylene was added. Xylene was removed after a holding time of 60 minutes at 130 ° C in vacuum. 50 wt .-% solution in benzyl alcohol, the condensate had a viscosity of 12,170 mPa · s (25 ° C).</li><li>3) 284 g of the condensate of Example 1 were mixed with 1.42 g of TDI-80, dissolved in 10 ml of dried xylene, at 130 ° C in about 30 min. Was added. Xylene was removed in vacuo after a holding time of 60 minutes at 130 ° C. 50 wt .-% solution in benzyl alcohol, the condensate had a viscosity of 8120 mPa · s (25 ° C).</li><li>4) had 280 g of a condensate according to Example 1, wt .-% solution in benzyl alcohol 50, a viscosity of 5530 mPa · s (25 ° C), was at 130 ° C in 30 min. With 0.7 g TDI -80, dissolved in 10 ml of dried xylene, was added. Xylene was removed in vacuo after a holding time of 60 minutes at 130 ° C. 50 wt .-% solution in benzyl alcohol, the condensate had a viscosity of 9000 mPa · s (25 ° C).</li><li>5) had 281 g of a condensate according to Example 1, wt .-% solution in benzyl alcohol 50, a viscosity of 5530 mPa · s (25 ° C), was at 130 ° C in 30 min. With 2.81 g of phenyl isocyanate dissolved in 10 ml of dried xylene, was added. Xylene was removed in vacuo after a holding time of 60 minutes at 130 ° C. 50 wt .-% solution in benzyl alcohol, the condensate had a viscosity of 5500 mPa · s (25 ° C).</li><li>6) 247 g of a condensate according to Example 1, wt .-% solution in benzyl alcohol 50, a viscosity of 5530 mPa · s (25 ° C) was formulated at 130 ° C with 0.5 ml of a 1% solution was added. 1.23 g of TDI-80, dissolved in 15 ml of dried xylene of dibutyltin dilaurate in xylene and then in 30 min. Xylene was removed after a holding time of 60 minutes at 130 ° C in vacuum. 50 wt .-% solution in benzyl alcohol, the condensate had a viscosity of 7680 mPa · s (25 ° C).</li><li>7) 231 g of a condensate according to Example 1, wt .-% solution in benzyl alcohol 50, a viscosity of 4750 mPa · s (25 ° C) was formulated at 130 ° C with 0.5 ml of a 1% solution of dibutyltin dilaurate in xylene and then in 30 min. with 1.15 g isophorone diisocyanate dissolved in 15 ml of dried xylene, was added. Xylene was removed in vacuo after a holding time of 60 minutes at 130 ° C. 50 wt .-% solution in benzyl alcohol, the condensate had a viscosity of 5730 mPa · s (25 ° C).</li><li>8) 259 g of a condensate according to Example 1, wt .-% solution in benzyl alcohol 50, a viscosity of 5530 mPa · s (25 ° C) was formulated at 130 ° C with 0.5 ml of a 1% solution of dibutyltin dilaurate in xylene and then in 30 min. with 1.30 g trimethylhexamethylene diisocyanate (2,2,4, 2,4,4-mixture of isomers) dissolved in 15 ml of dried xylene. Xylene was removed in vacuo after a holding time of 60 minutes at 130 ° C. 50 wt .-% solution in benzyl alcohol, the condensate had a viscosity of 7160 mPa · s (25 ° C).</li><li>9) had 259 g of a condensate according to Example 1, wt .-% solution in benzyl alcohol 50, a viscosity of 4750 mPa · s (25 ° C) was dissolved at 130 ° C with 1.0 ml of a 1% solution of dibutyltin dilaurate in xylene and then in 30 min. with 2.6 g of phenyl isocyanate, dissolved in 20 ml of dried xylene, was added. Xylene was removed in vacuo after a holding time of 60 minutes at 130 ° C. 50 wt .-% solution in benzyl alcohol, the condensate had a viscosity of 4850 mPa · s (25 ° C).</li><li>10) 185 g of a condensate according to Example 1, wt .-% solution in benzyl alcohol 50, a viscosity of 5530 mPa · s (25 ° C) was formulated at 130 ° C with 105 ml of a 1% solution of dibutyltin dilaurate dissolved in xylene and then in 30 min. with 3.78 g of phenyl isocyanate in 15 ml of dried xylene. Xylene was removed in vacuo after a holding time of 60 minutes at 130 ° C. 50 wt .-% solution in benzyl alcohol, the condensate had a viscosity of 4240 mPa · s (25 ° C).</li><li>11) In a dried N₂ atmosphere 250 g TDI 80 were heated to 60 ° C with stirring. 3 ml of a 1% solution of dibutyltin dilaurate in xylene were added. In 120 Min. Are added 129.5 g of dried ethyl glycol. Then the mixture was held for a further 120 min. At 60 ° C until the NCO content of this Halburethans 15 to 16 wt .-%, respectively.</li><li>12) 220 g of a condensate according to Example 1, wt .-% solution in benzyl alcohol 50, a viscosity of 4490 mPa · s (25 ° C) was formulated strength at 130 ° C with 0.5 ml of a 1% solution of dibutyltin dilaurate in xylene and then in 30 min. with 4.42 g of the above Halburethans dissolved in 20 ml of dried xylene, was added. Xylene was removed in vacuo after a holding time of 60 minutes at 130 ° C. 50 wt .-% solution in benzyl alcohol, the condensate had a viscosity of 5130 mPa · s (25 ° C).</li></ul>

II. Preparation of the condensation products (dispersants) A (c) with the catalysts mentioned under C₂.

<ul><li>1) 500 g of a polyethylene glycol having an average molecular weight of 4000 and 115.5 g of a polyglycidyl ether based on bisphenol A having an epoxide equivalent weight of 185 were heated together to 120 ° C. They set to 2 g of BF₃-amine complex "Anchor" 1040 and heated to 170 ° C. The epoxy equivalent was checked. In three portions further 0.85 g of the amine complex "Anchor" 1040 were added. After reaching the epoxy equivalent of 1,940, having a 20% higher condensation of the reactants is as it corresponds to the conversion of the hydroxyl group of the polyethylene glycol, the reaction was terminated. The equivalent ratio OH / epoxy ratio was 1: 2.5.</li><li>2) 500 g of a polyethylene glycol having an average molecular weight of 4,000 and 92.5 g of a polyglycidyl ether based on bisphenol A having an epoxide equivalent weight of 185 were heated together to 120 ° C. They set to 2 g BF₃-monoethylamine and heated to 150 ° C. The epoxy equivalent was checked. After reaching the epoxy equivalent of 3140, which is a 25% higher condensation of the reactants is as it corresponds to the conversion of the hydroxyl groups of the polyethylene glycol, the reaction was terminated. The equivalent ratio OH / epoxy ratio was 1: 2.0.</li><li>3) 250 g of a condensate in accordance with Example 1 above was mixed at 130 ° C with 1.0 ml of a 1% solution of dibutyltin dilaurate in xylene, and then dissolved in 30 min. With 6.25 g of TDI-80 in 40 ml of dried xylene were added. Xylene was removed in vacuo after a holding time of 60 min. At 130 ° C. 50 wt .-% solution in benzyl alcohol, the condensate had a viscosity of 3750 mPa · s (25 ° C) and an epoxide equivalent of 3750th</li><li>4) 250 g of a condensate in accordance with the above Example 2, which had an epoxy equivalent of 2400 was, at 130 ° C in 30 min. With 250 g isophorone diisocyanate dissolved in 20 ml of dried xylene, was added. Xylene was removed in vacuo after a holding time of 60 min. At 130 ° C. 50 wt .-% solution in benzyl alcohol, the condensate had a viscosity of 880 mPa · s (25 ° C).</li></ul>

III. Examples of the preparation of the dispersion according to the invention using the condensation products according to Examples 2-11 I.

<ul><li>1) In a 2 l three-necked flask equipped with a thermometer, paddle stirrer, reflux condenser and dropping funnel, 325 g of an epoxy resin based on bisphenol A having an epoxy equivalent of 183 with 98 g of bisphenol A and 27 g of the dispersant I.2) dissolved implemented in 27 g of benzyl alcohol, in the presence of 750 mg of triphenylphosphine at 150 ° to 170 ° C until an epoxy equivalent of 510-530. It was diluted with cooling with 60 g of methoxypropanol. With a stirring speed of 800 rpm and lowering the temperature to 70 - 60 ° C were in a period of 5 - 30 min evenly added 85 grams of deionized water to obtain an aqueous dispersion being that then deionized with 163 g of water. was further diluted. The dispersion had a solids content of 53.7 wt .-%, a viscosity of 4000 mPas (Brookfield, spindle 2 at 6 rpm) and a particle size of 0.50 microns.</li><li>2) In a 2 l three-necked flask equipped with a thermometer, paddle stirrer, reflux condenser and dropping funnel, 325 g of an epoxy resin based on bisphenol A having an epoxy equivalent of 183 with 98 g of bisphenol A and 27 g of the dispersant I.2) were dissolved in 27 g benzyl alcohol, in the presence of 750 mg of triphenylphosphine at 150 ° to 170 ° C until an epoxy equivalent of 520-530. It was diluted with cooling with 60 g of methoxypropanol. With a stirring speed of 800 rpm and lowering the temperature to 70 - 60 ° C were in a period of 5 - 30 min evenly added 85 grams of deionized water to obtain an aqueous dispersion being that then deionized with 170 g of water. was further diluted. The dispersion had a solids content of 54.2 wt .-%, a viscosity of 5200 mPas (Brookfield, spindle 3 at 6 rpm) and a particle size of 0.45 microns.</li><li>3) In a 2 l three-necked flask equipped with a thermometer, paddle stirrer, reflux condenser and dropping funnel, 325 g of an epoxy resin based on bisphenol A with an epoxy equivalent of 183 with 120 g of bisphenol A and 27 g of the dispersant I.4) were dissolved in 27 g benzyl alcohol, in the presence of 700 mg of triphenylphosphine at 150 ° to 170 ° C until an epoxy equivalent of 510-530. It was diluted with cooling with 60 g of methoxypropanol. At a stirring speed of 800 rpm and lowering the temperature to 70 - 60 ° C were in a period of 5 - 30 min uniformly added to 85 g of deionized water to obtain an aqueous dispersion being, the then with about 215 g. deionized water was further diluted. The dispersion had a solids content of 54.2 wt .-%, a viscosity of 4900 mPas (Brookfield, spindle 3 at 6 rpm) and a particle size of 0.46 microns.</li><li>4) In a 2 l three-necked flask equipped with a thermometer, paddle stirrer, reflux condenser and dropping funnel, 325 g of an epoxy resin based on bisphenol A with an epoxy equivalent of 183 with 120 g of bisphenol A and 27 g of the dispersant I.5) were dissolved in 27 g benzyl alcohol, in the presence of 700 mg of triphenylphosphine at 150 ° to 170 ° C until an epoxy equivalent of 510-530. It was diluted with cooling with 60 g of methoxypropanol. At a stirring speed of 800 rpm and lowering the temperature to 70 - 60 ° C were in a period of 5 - 30 min uniformly added to 85 g of deionized water to obtain an aqueous dispersion being, the then with about 215 g. deionized water was further diluted. The dispersion had a solids content of 53.2 wt .-%, a viscosity of 4950 mPas (Brookfield, spindle 3 at 6 rpm) and a particle size of 0.50 microns.</li><li>5) In a 2 l three-necked flask equipped with a thermometer, paddle stirrer, reflux condenser and dropping funnel, 325 g of an epoxy resin based on bisphenol A with an epoxy equivalent of 183 with 120 g of bisphenol A and 27 g of the dispersant I.6) were dissolved in 27 g benzyl alcohol, in the presence of 700 mg of triphenylphosphine at 150 ° to 170 ° C until an epoxy equivalent of 510-530. It was diluted with cooling with 60 g of methoxypropanol. At a stirring speed of 800 rpm and lowering the temperature to 70 - 60 ° C were in a period of 5 - 30 min uniformly added to 85 g of deionized water to obtain an aqueous dispersion being, the then with about 215 g. deionized water was further diluted. The dispersion had a solids content of 53.3 wt .-%, a viscosity of 4250 mPas (Brookfield, spindle 3 at 6 rpm) and a particle size of 0.45 microns.</li><li>6) In a 2 l three-necked flask equipped with a thermometer, paddle stirrer, reflux condenser and dropping funnel, 325 g of an epoxy resin based on bisphenol A with an epoxy equivalent of 183 with 120 g of bisphenol A and 27 g of the dispersant I.7) were dissolved in 27 g benzyl alcohol, in the presence of 700 mg of triphenylphosphine at 150 ° to 170 ° C until an epoxy equivalent of 510-530. It was diluted with cooling with 60 g of methoxypropanol. At a stirring speed of 800 rpm and lowering the temperature to 70 - 60 ° C were in a period of 5 - 30 min uniformly added to 85 g of deionized water to obtain an aqueous dispersion being, the then with about 215 g. deionized water was further diluted. The dispersion had a solids content of 52.9 wt .-%, a viscosity of 4500 mPas (Brookfield, spindle 3 at 6 rpm) and a particle size of 0.39 microns.</li><li>7) In a 2 l three-necked flask equipped with a thermometer, paddle stirrer, reflux condenser and dropping funnel, 325 g of an epoxy resin based on bisphenol A with an epoxy equivalent of 183 with 120 g of bisphenol A and 27 g of the dispersant I.8) were dissolved in 27 g benzyl alcohol, in the presence of 700 mg of triphenylphosphine at 150 ° to 170 ° C until an epoxy equivalent of 520-540. It was diluted with cooling with 60 g of methoxypropanol. At a stirring speed of 800 rpm and lowering the temperature to 70 - 60 ° C were in a period of 5 - 30 min uniformly added to 85 g of deionized water to obtain an aqueous dispersion being, the then with about 215 g. deionized water was further diluted. The dispersion had a solids content of 54.0 wt .-%, a viscosity of 4700 mPas (Brookfield, spindle 3 at 6 rpm) and a particle size of 0.42 microns.</li><li>8) In a 2 l three-necked flask equipped with a thermometer, paddle stirrer, reflux condenser and dropping funnel, 325 g of an epoxy resin based on bisphenol A with an epoxy equivalent of 183 with 120 g of bisphenol A and 27 g of the dispersant I.9) were dissolved in 27 g benzyl alcohol, in the presence of 700 mg of triphenylphosphine at 150 ° to 170 ° C until an epoxy equivalent of 520-530. It was diluted with cooling with 60 g of methoxypropanol. At a stirring speed of 800 rpm and lowering the temperature to 70 - 60 ° C were in a period of 5 - 30 min uniformly added to 85 g of deionized water to obtain an aqueous dispersion being, the then with about 215 g. deionized water was further diluted. The dispersion had a solids content of 53.2 wt .-%, a viscosity of 4950 mPas (Brookfield, spindle 3 at 12 rpm) and a particle size of 0.50 microns.</li><li>9) In a 2 l three-necked flask equipped with a thermometer, paddle stirrer, reflux condenser and dropping funnel, 325 g of an epoxy resin based on bisphenol A with an epoxy equivalent of 183 with 120 g of bisphenol A and 27 g of the dispersant I.10) were dissolved in 27 g benzyl alcohol, in the presence of 700 mg of triphenylphosphine at 150 ° to 170 ° C until an epoxy equivalent of 510-530. It was diluted with cooling with 60 g of methoxypropanol. At a stirring speed of 800 rpm and lowering the temperature to 70 - 60 ° C were in a period of 5 - 30 min uniformly added to 85 g of deionized water to obtain an aqueous dispersion being, the then with about 215 g. deionized water was further diluted. The dispersion had a solids content of 53.2 wt .-%, a viscosity of 5000 mPas (Brookfield, spindle 3 at 12 rpm) and a particle size of 0.44 microns.</li><li>11) In a 2 l three-necked flask equipped with a thermometer, paddle stirrer, reflux condenser and dropping funnel, 325 g of an epoxy resin based on bisphenol A with an epoxy equivalent of 183 with 120 g of bisphenol A and 27 g of the dispersant I.4) were dissolved in 27 g benzyl alcohol, in the presence of 700 mg of triphenylphosphine at 150 ° to 170 ° C until an epoxy equivalent of 510-530. It was diluted with cooling with 60 g of methoxypropanol. At a stirring speed of 800 rpm and lowering the temperature to 70 - 60 ° C were in a period of 5 - 30 min uniformly added to 85 g of deionized water to obtain an aqueous dispersion being, the then with about 215 g. deionized water was further diluted. The dispersion had a solids content of 53.1 wt .-%, a viscosity of 2575 mPas (Brookfield, spindle 2 at 12 rpm) and a particle size of 0.53 microns.</li></ul>

IV. Examples of the preparation of the dispersions according to the invention using the condensation products of Examples II. 3 to 4

<ul><li>1) In a 2 l three-necked flask equipped with a thermometer, paddle stirrer, reflux condenser and dropping funnel, 325 g of an epoxy resin based on bisphenol A having an epoxide equivalent weight of 183 with 98 g of bisphenol A and 27 g of the dispersant II.3) were dissolved in 27 g benzyl alcohol, in the presence of 600 mg of triphenylphosphine at 150 ° to 160 ° C until an epoxy equivalent of about 530th It was diluted with cooling with 60 g of methoxypropanol. Below a temperature of 70 ° C 85 g which subsequently populated with approximately 235 g deionized water at a stirring speed of 800 revolutions per minute over a period of 5 min. Added and stirred deionized water to obtain an aqueous dispersion being diluted further has been. The dispersion had a solids content of 53.0 wt .-%, a viscosity of 650 mPa.s (Brookfield, spindle 2 at 30 rpm) and a particle size 0.65 micron.</li><li>2) In a 2 l three-necked flask equipped with a thermometer, paddle stirrer, reflux condenser and dropping funnel, 325 g of an epoxy resin based on bisphenol A having an epoxide equivalent weight of 183 with 98 g of bisphenol A and 54 g of the dispersant II.4) dissolved implemented in 54 g of benzyl alcohol, in the presence of 600 mg of triphenylphosphine at 150 ° to 160 ° C until an epoxy equivalent of about 550th It was diluted with cooling with 33 g of methoxypropanol. Below a temperature of 70 ° C 85 g which subsequently populated with approximately 230 g deionized water at a stirring speed of 800 revolutions per minute over a period of 5 min. Added and stirred deionized water to obtain an aqueous dispersion being diluted further has been. The dispersion, diluted to a solids content of 52.9 wt .-%, a viscosity of 2900 mPa.s (Brookfield, spindle 2 at 12 rpm) and a particle size of 0.62 microns.</li></ul>

On the outstanding samples of these dispersions forms over a period of several hours no firm skin. That has occurred due to evaporation at the surface viscosity-related thickening is homogeneous verrührbar again.

V. Application Techn. exams

A dispersion of the invention (→ Example II.2) and a dispersion of the prior art (EP-A-0081163) were subjected to a series of performance tests. The result show the two tables below. 1 and 2<tables id="tabl0001" num="0001"><table frame="all"><title>Table 1</title><tgroup cols="3" colsep="1" rowsep="0"><colspec colnum="1" colname="col1" colwidth="52.50mm" /><colspec colnum="2" colname="col2" colwidth="52.50mm" /><colspec colnum="3" colname="col3" colwidth="52.50mm" /><thead valign="top"><row><entry namest="col1" nameend="col1" /><entry namest="col2" nameend="col2" align="center">According to the invention (Example III.7)</entry><entry namest="col3" nameend="col3" align="center">Comparison (dispersion according to EP-A-0,081,163, Ex. 2)</entry></row></thead><tbody valign="top"><row><entry namest="col1" nameend="col1" align="left">dispersion</entry><entry namest="col2" nameend="col2" align="right">100 parts</entry><entry namest="col3" nameend="col3" align="right">100 parts</entry></row><row><entry namest="col1" nameend="col1" align="left">Hardener according Eur.P. 0,000,605, Ex. 5c</entry><entry namest="col2" nameend="col2" align="right">20 parts</entry><entry namest="col3" nameend="col3" align="right">20 parts</entry></row><row><entry namest="col1" nameend="col1" align="left">Dust dry (RT):</entry><entry namest="col2" nameend="col2" align="right">45 min</entry><entry namest="col3" nameend="col3" align="right">110 min</entry></row><row><entry namest="col1" nameend="col1" align="left">To touch (RT):</entry><entry namest="col2" nameend="col2" align="right">110 min</entry><entry namest="col3" nameend="col3" align="right">180 min</entry></row><row><entry namest="col1" nameend="col1" align="left">Pendulum hardness (24):</entry><entry namest="col2" nameend="col2" align="right">75 s</entry><entry namest="col3" nameend="col3" align="right">30 s</entry></row><row><entry namest="col1" nameend="col1" align="left">Pendulum Hardness (7d):</entry><entry namest="col2" nameend="col2" align="right">145 s</entry><entry namest="col3" nameend="col3" align="right">85 s</entry></row><row><entry namest="col1" nameend="col1" align="left">Film haze after:</entry><entry namest="col2" nameend="col2" align="right">3.5 hours</entry><entry namest="col3" nameend="col3" align="right">3.0 hours</entry></row><row><entry namest="col1" nameend="col1" align="left">Water resistance after 24 hours of storage:</entry><entry namest="col2" nameend="col2" align="right">1</entry><entry namest="col3" nameend="col3" align="right">3</entry></row><row><entry namest="col1" nameend="col3" align="justify">1. Dust-dry: scattered on the film beads can no longer be removed after curing with a brush. 2. Non-tacky: the glass beads can be removed with a brush after curing. 3. Konig pendulum hardness: DIN 53 157 4. film haze: films are applied every half hour after mixing the dispersion and hardener on glass plates in 200 microns thickness. The appearance of turbidity in the film is the test and the end of the processing time. 5. Water resistance after 24 h, storage at room temperature: reared on glass plates with 200 micron layer thickness films are tested h storage in H₂O at room temperature after 24th Scale: 0 = excellent, 5 = poor.</entry></row></tbody></tgroup></table></tables><tables id="tabl0002" num="0002"><table frame="all"><title>Table 2</title><tgroup cols="3" colsep="1" rowsep="0"><colspec colnum="1" colname="col1" colwidth="52.50mm" /><colspec colnum="2" colname="col2" colwidth="52.50mm" /><colspec colnum="3" colname="col3" colwidth="52.50mm" /><thead valign="top"><row><entry namest="col1" nameend="col3" align="center">(Examination of the gloss retention)</entry></row><row><entry namest="col1" nameend="col1" /><entry namest="col2" nameend="col2" align="center">According to the invention (Example III.7)</entry><entry namest="col3" nameend="col3" align="center">Comparison (dispersion according to EP-A-0,081,163, Ex. 2)</entry></row></thead><tbody valign="top"><row><entry namest="col1" nameend="col1" align="left">dispersion</entry><entry namest="col2" nameend="col2" align="right">100 parts</entry><entry namest="col3" nameend="col3" align="right">100 parts</entry></row><row><entry namest="col1" nameend="col1" align="left">TiO₂</entry><entry namest="col2" nameend="col2" align="right">35.4 parts</entry><entry namest="col3" nameend="col3" align="right">32.6 parts</entry></row><row><entry namest="col1" nameend="col1" align="left">hexamethoxymethylmelamine</entry><entry namest="col2" nameend="col2" align="right">0.7 parts</entry><entry namest="col3" nameend="col3" align="right">0.65 parts</entry></row><row><entry namest="col1" nameend="col1" align="left">H₂O</entry><entry namest="col2" nameend="col2" align="right">33 parts</entry><entry namest="col3" nameend="col3" align="right">25 parts</entry></row><row><entry namest="col1" nameend="col1" align="left">Hardener according Eur.P. 0,000,605, Ex. 5c</entry><entry namest="col2" nameend="col2" align="right">20.6 parts</entry><entry namest="col3" nameend="col3" align="right">19.0 parts</entry></row><row><entry namest="col1" nameend="col1" align="left">Gloss stability * immediately</entry><entry namest="col2" nameend="col2" align="right">97</entry><entry namest="col3" nameend="col3" align="right">63</entry></row><row><entry namest="col1" nameend="col1" align="left">30 min.</entry><entry namest="col2" nameend="col2" align="right">100</entry><entry namest="col3" nameend="col3" align="right">69</entry></row><row><entry namest="col1" nameend="col1" align="left">1 hour</entry><entry namest="col2" nameend="col2" align="right">98</entry><entry namest="col3" nameend="col3" align="right">67</entry></row><row><entry namest="col1" nameend="col1" align="left">2 hours</entry><entry namest="col2" nameend="col2" align="right">93</entry><entry namest="col3" nameend="col3" align="right">59</entry></row><row><entry namest="col1" nameend="col1" align="left">3 h</entry><entry namest="col2" nameend="col2" align="right">85</entry><entry namest="col3" nameend="col3" align="right">46</entry></row><row><entry namest="col1" nameend="col1" align="left">4 h</entry><entry namest="col2" nameend="col2" align="right">47</entry><entry namest="col3" nameend="col3" align="right">38</entry></row><row><entry namest="col1" nameend="col1" align="left">5 h</entry><entry namest="col2" nameend="col2" align="right">29</entry><entry namest="col3" nameend="col3" align="right">-</entry></row></tbody></tgroup><tgroup cols="3" colsep="0" rowsep="0"><colspec colnum="1" colname="col1" colwidth="52.50mm" /><colspec colnum="2" colname="col2" colwidth="52.50mm" /><colspec colnum="3" colname="col3" colwidth="52.50mm" /><tbody valign="top"><row><entry namest="col1" nameend="col3" align="justify">* According to DIN 67530; 60 ° ∢</entry></row></tbody></tgroup></table></tables>