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. 23, 1981
Filed:
Feb. 28, 1980
Charles Danick, Plymouth, MN (US);
K A Panandiker, Maple Grove, MN (US);
Cargill, Incorporated, Minneapolis, MN (US);
Abstract
The invention is directed to a polyester resin, and a method for making it, for use in a powder coating. The resin comprises on oligomer of neopentyl glycol or cyclohexane dimethanol and terephthalic acid, isophthalic acid or dimethyl terephthalate in a mole ratio between about 1.15 and about 1.50, the oligomer being reacted with trimellitic anhydride to provide a trimellitate with the mole ratio oligomer to trimellitate being in the range of between about 2.5 and 5.5. The trimellitate is reacted with a dicarboxylic anhydride or acid with the mole ratio of trimellitate to dicarboxylic anhydride or acid between about 1.5 and about 2.5. The polyester resin has an ICI viscosity at 200.degree. C. between about 20 poises and about 60 poises, an acid value of less than 30, a hydroxyl value between about 20 and about 60, and an equivalent weight between about 935 and about 2800.