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:
Dec. 31, 2002
Filed:
Sep. 21, 2000
Ronald R. Ambrose, Pittsburgh, PA (US);
Anthony M. Chasser, Allison Park, PA (US);
Shengkui Hu, Glenshaw, PA (US);
John R. Schneider, Glenshaw, PA (US);
Jackie L. Smith, Gibsonia, PA (US);
PPG Industries Ohio, Inc., Cleveland, OH (US);
Abstract
The present invention provides a crosslinking agent having reactive benzoxazine groups which is the ungelled reaction product of (a) at least one mono-hydroxy aromatic compound and (b) at least one aminotriazine compound having one or less non-alkylated NH group present in a molar ratio of reactant (a) to reactant (b) ranging from 1.0 to 3.0: 1.0, provided that where reactant (a) is a single ring monohydroxy aromatic compound, the molar ratio of reactant (a) to reactant (b) ranges from 1.0 to 1.8:1.0 and from 2.2 to 3.0:1.0. The crosslinking agent is essentially free of hydroxyl functionality and has a glass transition temperature of at least 25° C. The present invention is further directed to a method for preparing the above-described crosslinking agent. Also provided is a curable powder coating composition comprising a solid particulate, film-forming mixture of (A) a polymer having functional groups reactive with aminotriazine and/or benzoxazine groups, the polymer having a glass transition temperature of at least 30° C.; and (B) the previously described crosslinking agent. Multilayer composite coating compositions are also provided including a base coat deposited from a film-forming composition and a topcoat over the base coat. The topcoat is deposited from the curable powder coating composition described above. The present invention further provides coated substrates.