Process for producing improved coating compositions

Abstract

Abstract Coating compositions, primarily for curing by electron beams, are prepared by a process characterized in that from about 1 mole of a non-aromatic cyclic dicarboxylic acid anhydride is reacted at from about 80°-90° C. with from about 1 mole of a monohydroxyalkyl(meth)acrylate having from about 2 to 12 C-atoms in the alkyl radical, until substantially the acid value of the semi-ester is reached. The resultant semi-ester is reacted at from about 90°-100° C. with a diepoxide, optionally using esterification catalysts and polymerization inhibitors, until an acid value of below about 5 mg KOH/g is obtained. The reaction product obtained is thereafter reacted at from about 70°-80° C. with from about 5-90 mole percent, preferably 20 to 50 mole percent, calculated on the hydroxy groups present, with an unsaturated monoisocyanate having the formula ##STR1## wherein R is an aromatic, aliphatic or cycloaliphatic radical, R 1 is hydrogen or CH 3 , and R 2 is a straight chain or branched hydrocarbon radical having from about 2 to 12 C-atoms, until an isocyanate value of substantially zero is obtained. The reaction product can, optionally, be dissolved with one or more polymerizable monomers. The coating compositions, when applied as a film and cured by electron beams using low doses of irradiation give films with excellent resistance to chemicals and weather, having high surface hardness and excellent flexibility.

Inventors

• 👤 Georgios (Georg) Pampouchidis

Bibliographic Details