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, 1995
Filed:
Jul. 15, 1993
Toshikazu Umemura, Toyonaka, JP;
Mitsubishi Gas Chemical Company, Inc., Tokyo, JP;
Abstract
Disclosed is a process for producing a grafted polycarbonate resin for optical use, which comprises adding to an aqueous suspension of an aromatic polycarbonate resin having radical-polymerizable unsaturated terminal group on a molecule wherein the aromatic polycarbonate resin has an average particle diameter of 0.1 to 5 mm and an apparent density of 0.2 to 0.9 g/cm.sup.3, a vinyl monomer and a radical-polymerization initiator, heating the aqueous suspension at a lower temperature by 5.degree. C. to 20.degree. C. than the decomposition temperature for a half-life period of 10 hours of the radical-polymerization initiator, thereby impregnating the polycarbonate resin with the vinyl monomer and the radical-polymerization initiator, then elevating the temperature to the range of from a lower temperature by 50.degree. C. to a higher temperature by 30.degree. C. than the decomposition temperature for a half-life period of 10 hours of the radical-polymerization initiator, thereby conducting a graft-polymerization reaction to obtain 90% by weight or more of conversion of vinyl monomer.