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:
Oct. 26, 1993
Filed:
Oct. 17, 1991
Applicant:
Inventors:
Hiroshi Ohishi, Kawasaki, JP;
Masao Kimura, Kawasaki, JP;
Shinji Inaba, Kawasaki, JP;
Masanao Kawabe, Kawasaki, JP;
Assignees:
Nippon Steel Corporation, Tokyo, JP;
Nippon Steel Chemical Co., Ltd., Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
C08G / ;
U.S. Cl.
CPC ...
525132 ; 525177 ;
Abstract
A process is disclosed for the preparation of aromatic polyester-polystyrene block copolymers by solution polycondensation of styrene polymers (A) having terminal functional groups reactive with acid halide or hydroxyl groups, aromatic dihydroxy compounds (B), and aromatic dicarboxylic acid dihalides (C) at (A)/[(B)+(C)] (by weight) of 5/95 to 80/20 and the polymers are suitable as molding materials for optical instruments for their good transparency, particularly low birefringence, low melt viscosity, and good mechanical strength.