The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 20, 2000
Filed:
Sep. 18, 1997
Karen A Barkac, Murrysville, PA (US);
Joseph Benga, Allison Park, PA (US);
John M Furar, Pittsburgh, PA (US);
Charles M Kania, Natrona Heights, PA (US);
Gaurav Agrawal, Pittsburgh, PA (US);
Paul H Lamers, Allison Park, PA (US);
PPG Industries Ohio, Inc., Cleveland, OH (US);
Abstract
Cured thermoset multilayered composite coatings with a powder clear coat and a waterborne base coat have improved chip resistance for the coating. The waterborne base coat composition has one or more crosslinkable film-forming polymers, one or more crosslinking agents for crosslinking the film-forming polymer, and one or more pigments. This basecoat is applied to a bare or previously painted substrate to give a film thickness in the range of about 0.1 to 3 mils (2.54 to 76.2 microns). The basecoat is dehydrated from treatment at a temperature from ambient to an elevated temperature of up to about 90.degree. C. for up to about 15 minutes before it is contacted with powder clear coating composition. The powder clear coating composition has a predominant amount of one or more crosslinkable, meltable and mobile film-forming polymer and/or copolymer having a weight average molecular weight of one or polymers/copolymers in the range of about 2000 to about 6000. The film-forming polymer or copolymer has an amount of functionality for crosslinking of at least 40 weight percent of the total resin solids for the polymers. The glass transition temperature for the powder coating composition is at least about 25.degree. C. The powder coating composition for the clear coat also has one or more crosslinking agents and when cured has a film thickness in the range of about 35 to about 100 microns. The basecoat and clear coat are co-cured. Optionally, one or more primer coats may be beneath the basecoat.