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. 12, 2001
Filed:
Mar. 23, 2000
Mitsunori Ito, Ichihara, JP;
Idemitsu Petrochemical Co., Ltd., Tokyo, JP;
Abstract
Provided is a process for producing a polycarbonate, which comprises preparing a polycarbonate prepolymer through prepolymerization followed by polymerizing the prepolymer in a solid phase in the presence of a phosphorus-containing basic compound serving as a catalyst in an atmosphere of a poor solvent gas. Preferably, the poor solvent is one in which the polycarbonate has a solubility of at most 0.1% by weight, more preferably, a linear aliphatic or cycloaliphatic hydrocarbon having from 5 to 18 carbon atoms. The process is efficient in producing high-quality polycarbonates having a high molecular weight.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile