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:
Aug. 17, 1993
Filed:
Sep. 27, 1991
Christopher D Selvig, Pittsburgh, PA (US);
John C Crano, Murrysville, PA (US);
PPG Industries, Inc., Pittsburgh, PA (US);
Abstract
Describes polymerizable organic resin compositions of from about 70 to 90 weight percent of a polyol(allyl carbonate), e.g., diethylene glycol bis(allyl carbonate), and from about 30 to 70 weight percent of aliphatic polyurethane having terminal allylic unsaturation. The polymerizable compositions have initiated pot life times of at least about 24 hours at 25.degree. C. and castings that have low yellowness (b*) values. Polymerizates prepared from such compositions may be used to prepare photochromic articles, e.g., lenses, by incorporating a photochromic substance, e.g., by thermal transfer, into the polymerizate.