Beverage containers coated with a water-based liner
AssigneePPG Industries, Inc.
InventorWilliam J. Birkmeyer
Life of this patent
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Abstract
Metal containers suitable for packaging beer and other beverages have as the internal sanitary liner a film of a water-based coating composition prepared by dissolving or dispersing in aqueous medium an at least partially neutralized reaction product of a polyepoxide having a 1,2-epoxy equivalency greater than 1.0 and an amino acid containing at least one amine group and at least one carboxyl group, wherein the amine groups of the amino acid are preferentially reactive with the epoxy groups of the polyepoxide, and a curing or cross-linking agent. These compositions provide containers with cured liners which do not impart undesirable turbidity or taste characteristics to the beer, soft drinks or fruit juices packaged therein.
Claims10
A metal container having an internal surface coated with a cured layer of a water-based coating composition comprising an aqueous medium having dissolved or dispersed therein:
- (a) an at least partially base neutralized reaction product of:
- (1) a polyepoxide having a 1,2-epoxy equivalency of greater than 1.0, and
- (2) an aromatic amino acid containing at least one amine group and at least one carboxyl group, in which the amine group and the carboxyl group are both attached to the aromatic ring, wherein the amine groups of said amino acid are preferentially reactive with the epoxy groups of said polyepoxide;
- said reaction product having unreacted carboxyl groups which are neutralized with a base;
- and
- (b) from about 3 to about 30 percent by weight based on the weight of (a) and (b) of a curing agent.
Dependencies are inferred from the claim text.