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. 01, 2006
Filed:
Mar. 31, 2004
Masaaki Miyamoto, Fukuoka, JP;
Takao Tayama, Fukuoka, JP;
Hiroshi Nakano, Kanagawa, JP;
Mitsubishi Chemical Corporation, Tokyo, JP;
Mitsubishi Engineering-Plastics Corporation, Tokyo, JP;
Abstract
A subject for the invention is to provide a branched aromatic polycarbonate which is excellent in hue and in melt characteristics such as melt strength. The invention provides a branched aromatic polycarbonate having a viscosity-average molecular weight of 16,000 or higher obtained by the transesterification method, characterized in that the ratio of the weight-average molecular weight (Mw) to number-average molecular weight (Mn) as measured by gel permeation chromatography and calculated for standard polystyrene (Mw/Mn) is in the range of from 2.8 to 4.5 and that the proportion of the number of moles of all structural units yielded by a rearrangement reaction in the course of melt polymerization reaction to 1 mol of structural units having the framework of an aromatic dihydroxy compound used as a starting material is higher than 0.3 mol % and not higher than 0.95 mol.