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:
Dec. 12, 1995
Filed:
Apr. 15, 1994
Daicel Chemical Industries, Ltd., Osaka, JP;
Abstract
A (co)polycarbonate composition mainly comprising a (co)polycarbonate having a limiting viscosity number [.eta.] of 0.2 to 1.0 dl/g and terminal hydroxyl groups in an amount of 20 mole % or below, based on all the terminal groups of the (co)polycarbonate, and is substantially free from any branched structure which might otherwise be formed by a side reaction. The (co)polycarbonate contains chlorine (causasive of discoloration) in an amount of 10 ppm or below and an alkali metal ion and/or an alkaline earth metal ion in an amount of 1 ppm or below. A process for preparing the above (co)polycarbonate composition by the melt transesterification process involves the reaction of a dihydroxy compound such as bisphenol A and a carbonic diester such as diphenyl carbonate with a nitrogen-containing basic compound (a), and/or, a compound (b) containing an element selected from the group consisting of elements belonging to Groups I, II, IV and V of the periodic table as a catalyst.