Patent ID: 6274649
Filing Date: 2001-08-14
Classification: C08G,C09D

Abstract:
An aqueous binder dispersion for cathodic electrodeposition coatings prepared by a process comprising:A) reacting togetherI. a precursor prepared at temperatures of from about 120 to about 180.degree. C. froma) a diepoxide compound or a mixture of diepoxide compounds, andb) an aromatic or aliphatic compound, having functionality selected from the group consisting of hydroxyl, carboxyl, phenol, and thiol groups, or a mixture of such compounds,in the presence of a catalyst selected from the group consisting of phosphine, a phosphine derivative and a phosphine salt;II. with at least one organic amine or a mixture of organic amines at a temperature between a bout 60 and about 130.degree. C. to given an epoxide/amine adduct;B) subsequently or simultaneously reacting at least one secondary hydroxyl group of the precursor with an unreacted epoxide group of the epoxide/amine adduct prepared in step A) at a temperature of from about 110 to about 150.degree. C.;C) adding a crosslinking agent at a temperature of less than about 150.degree. C.;D) neutralizing the resulting binder from steps A to C at a temperature of from about 90 to about 110.degree. C.; andE) dispersing the neutralized binder obtained in steps A to D in water,whereby the need for distillative removal of solvents after preparation of the dispersion is obviated.