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:
Jan. 12, 1999
Filed:
Dec. 19, 1996
Masanori Abe, Iwakuni, JP;
Keisuke Shinohara, Iwakuni, JP;
Wataru Funakoshi, Iwakuni, JP;
Katsushi Sasaki, Iwakuni, JP;
Teijin Limited, Osaka, JP;
Abstract
A polycarbonate copolymer which consists essentially of 5 to 95 mol % of recurring units containing a specific spiroglycol unit and 95 to 5 mol % of recurring units containing a specific biphenol unit, and has a reduced viscosity (.eta..sub.sp /c), measured at 20.degree. C. in a solution containing methylene chloride as a solvent and having a concentration of 0.5 g/dl, of at least 0.3 dl/g, a photoelasticity coefficient of 70.times.10.sup.-13 cm.sup.2 /dyne or less, and a glass transition temperature of at least 95.degree. C.; and a process for the production thereof. This polycarbonate copolymer is useful as a material for an information transmission medium or an information recording medium.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile