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:
Oct. 08, 2002
Filed:
Sep. 26, 2000
Mitsunori Ito, Ichihara, JP;
Shigeki Kuze, Ichihara, JP;
Idemitsu Petrochemical Co., Ltd., Tokyo, JP;
Abstract
Disclosed are polycarbonates which are obtained by preparing a polycarbonate prepolymer through prepolymerization followed by polymerizing it through solid-phase, swollen solid-phase or thin film melt-phase transesterification, and have a remaining monomer content of smaller than 100 ppm, especially a dihydroxy compound content of smaller than 100 ppm, or have an acetone soluble content of at most 3.5 or at most 3.0% by weight, or have a terminal hydroxyl fraction of smaller than 2 or smaller than 15 mol %; and optical materials and blow molding materials comprising the polycarbonate. The polycarbonates contain a reduced amount of impurities such as remaining monomers, oligomers and others and have improved physical properties including impact strength, and these are useful as optical materials and blow molding materials.