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. 24, 2008
Filed:
May. 26, 2004
Masaya Okamoto, Ibaraki, JP;
Jun-ichi Sugiyama, Ibaraki, JP;
Mitsuru Ueda, Tokyo, JP;
National Institute of Advanced Industrial Science and Technology, Tokyo, JP;
Idemitsu Kosan Co., Ltd., Tokyo, JP;
Abstract
Provided are a catalyst for producing polycarbonate comprising a reaction product obtained by reacting (a) a catalyst carrier containing nitrogen or phosphorus with (b) a palladium compound and (c) a metal compound having a redox catalytic ability and a production process for polycarbonate, comprising a first step in which an aromatic dihydroxy compound and monovalent phenol are reacted with carbon monoxide and oxygen to produce a polycarbonate prepolymer and a second step in which the above polycarbonate prepolymer is subjected to solid state polymerization to produce polycarbonate, wherein the above catalyst is used in the first step described above. The catalyst of the present invention is readily separated from polycarbonate and can repeatedly be used, and the above catalyst makes it possible to efficiently produce polycarbonate of a high quality without using harmful chlorine gas and phosgene and halogenated organic solvents such as dichloromethane and chloroform which are considered to exert an adverse effect on the environment.