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:
May. 27, 2014
Filed:
Sep. 30, 2013
Mitsubishi Chemical Corporation, Chiyoda-ku, JP;
Shingo Namiki, Fukuoka, JP;
Masanori Yamamoto, Fukuoka, JP;
Mitsubishi Chemical Corporation, Chiyoda-ku, JP;
Abstract
A method for producing a polycarbonate resin comprises a step of performing polycondensation through a transesterification reaction in the presence of a transesterification catalyst by using a dihydroxy compound as a raw material compound and a carbonic acid diester, wherein the dihydroxy compound comprises at least an aliphatic dihydroxy compound having an etheric oxygen atom on a hydroxy group, the raw material compound comprises the specific amount of a nitrogen-containing compound, and the production method of a polycarbonate resin comprises a step of previously heating the aliphatic dihydroxy compound at the specific temperature, holding the compound in the melted state for the specific time, and then mixing the melt with a carbonic acid diester.