Aqueous coating composition comprising self-emulsifiable ester of epoxy and acid containing addition polymer
AssigneeSCM Corporation
InventorsGeorge L. Brown, Arthur T. Spencer
Life of this patent
Estimating the term…
Abstract
Non-gelled compositions containing hydroxy ester copolymer having carboxyl groups and substantially free of oxirane groups are disclosed which are the esterification reaction product of (A) acidic addition copolymer; and (B) mixtures containing epoxy resin including both aromatic polyether containing oxirane groups and aromatic polyether devoid of oxirane groups, in which the mixture comprises at least 40% of the total resin solids and contains insufficient oxirane groups to react with all of the carboxyl groups in the copolymer. The resulting composition is neutralized with amine, is self-emulsifiable in water and is useful for coatings, e.g., for cans.
Claims5
A composition suitable for sanitary can coatings consisting essentially of a self-emulsified mixture substantially free of oxirane groups including a hydroxy ester copolymer containing carboxyl groups at least some of which, sufficient to achieve self-emulsification in water, are neutralized by volatile amine;
- which composition is the product of the reaction of:
- (A) an acidic addition copolymer having an acid number greater than 150 comprising a copolymer of monoethylenically unsaturated monomers selected from the group consisting of styrene, vinyl toluene, acrylic acid esters, methacrylic acid esters, acrylic acid and methacrylic acid containing at least about 30% by weight of acrylic or methacrylic acid based on the total weight of monomers;
- (B) a mixture containing (bisphenol-A)-epichlorohydrin polyether epoxy resin including at least 5% by weight of polyether epoxy resin containing oxirane groups and at least 25% by weight of said (bisphenol-A) polyether being terminated with bisphenol-A and devoid of oxirane groups, said mixture comprising at least 40% of the total resin solids and containing sufficient oxirane groups to provide a ratio of oxirane groups to carboxyl of 1:2 to 1:20;
- and
- conducted in the presence of a tertiary amine in amounts from 0.1% to 0.3% by weight of reactants subjected to esterification.
Dependencies are inferred from the claim text.