Composite coatings employing polyepoxides and polyacid curing agents in base coats
AssigneePPG Industries, Inc.
InventorsSamuel Porter, Jr., Dennis A. Simpson, William P. Blackburn
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Abstract
A color plus clear composite coating and process are disclosed. A pigmented or colored base coat is first applied to a substrate followed by the application of a transparent top coat to the base coat. The base coat composition is a liquid crosslinkable composition comprising a polyepoxide and a polyacid curing agent which comprises a half ester formed from reacting an acid anhydride with a polyol. The top coat composition is a powder coating. The resultant composite coating exhibits improved distinctness of image, making the composite coating particularly useful as an automotive top coat.
Claims16
An improved composite coating comprising a pigmented base coat over which is applied a clear powder top coat comprising a resin selected from the group consisting of an epoxy, a polyester and acrylic resin;
- the improvement comprising the base coat which comprises a liquid crosslinkable composition which consists essentially of a polyepoxide and a polyacid curing agent.
Dependencies are inferred from the claim text.