WASSERVERDÜNNBARE HARZE, VERFAHREN ZU IHRER HERSTELLUNG UND IHRE VERWENDUNG

Water-dilutable resins are obtained by reacting acid group-containing polymers with water-insoluble, hydroxyl group-containing aldehyde or ketone resins and neutralizing the reaction product. Resins (AB) with an acid number of 25-160 mg/g which are water-dilutable after neutralization, are obtained by the reaction of (A) 30-90 wt.% (based on solid content of reaction mixture) acid group-containing polymer(s) with an acid number of 30-240 mg/g selected from polyesters, di- and/or oligo-merised unsaturated aliphatic carboxylic acids and polymers of olefinic monomers; and (B) 10-70 wt.% water-insoluble aldehyde or ketone resin(s) with a hydroxyl number of 20-300 mg/g, a softening point of 60-140 degrees C and a number average molecular weight of 500-3000, obtained by condensation of ketones, ketones with aldehydes, ketones with urea or aldehydes with urea. Independent claims are also included for (a) aqueous solutions or dispersions of these resins, obtained by diluting the neutralized resin with water to a solid content of 30-50%; and (b) a process for the production of these resins by reacting components (A) and (B) at 100-250 degrees C until the product has an acid number of 25-160, optionally adding a water-miscible solvent and neutralizing with an aqueous solution of alkali hydroxide, ammonia or amine.