Film-forming compositions comprising carboxy-copolymers and polyepoxides and method of making same

Claim 1

A FILM FORMING COMPOSITION COMPRISING (1) A POLYEPOXIDE SELECTED FROM THE GROUP CONSISTING OF GLYCIDYL POLYETHERS OF POLYHYDIC ALCOHOLS AND PHENOLS, AND EPOXIDIZED ESTERS, POLYESTERS, DRYING OILS, DIOLEFINS AND CYCLIC ALDEHYDE CONDENSATES EACH HAVING AT LEAST TWO EPOXY GROUPS, AND (2) A SOLUTION OF A CARBOXY COPOLYMER FORMED FROM THIRTY TO EIGHTY-FIVE PARTS BY WEIGHT OF (A) AN ALKYL ESTER OF A MONOUNSATURATED MONOCARBOXYLIC ACID WHEREIN THE ALKYL GROUP HAS NOT OVER TEN CARBON ATOMS AND WHEREIN THE MONOCARBOXYLIC ACID IS SELECTED FROM THE GROUP CONSISTING OF ACRYLIC ACID AND METHACRYLIC ACID, AND FIFTEEN TO SEVENTY PARTS BY WEIGHT, THE TOTAL BEING ONE HUUNDRED, OF (B) AN ACID ESTER OF A BUTENEDIOIC ACID AND A SATURATED MONOHYDRIC ALCOHOL OF NOT OVER TWELVE CARBON ATOMS, SAID ALCOHOL CONTAINING ONLY CARBON, HYDROGEN AND OXYGEN AND BEING FREE OF OXYGEN-CONTAINING GROUPS OTHER THAN ETHER AND HYDROXYL GROUPS, THE RATIO OF (1) TO (2) BEING 0.7 TO 2 EPOXIDE EQUIVALENTS POLYEPOXIDE PER CARBOXY EQUIVALENT COPOLYMER, CONSIDERING AN EPOXIDE EQUIVALENT POLYEPOXIDE AS THE WEIGHT OF POLYEPOXIDE IN GRAMS PER EPOXIDE GROUP AND A CARBOXYL EQUIVALENT COPOLYMER AS THE WEIGHT OF COPOLYMER IN GRAMS PER CARBOXYL GROUP.