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:
Apr. 07, 1992
Filed:
Mar. 01, 1990
Applicant:
Inventors:
Frank J Onorato, Phillipsburg, NJ (US);
David E Nikles, Colonia, NJ (US);
Leroy McKenzie, Essex County, NJ (US);
Jeffrey A Schneider, Flemington, NJ (US);
Assignee:
Hoechst Celanese Corp., Somerville, NJ (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B32B / ;
U.S. Cl.
CPC ...
428412 ; 428409 ; 427163 ; 427164 ;
Abstract
Provided is a method for preparing an optical information medium which comprises a polycarbonate substrate. A polycarbonate substrate is subjected to an aqueous ammonia solution treatment at a temperature below ambient temperatures and for an extended period of time. This treatment occurs prior to assembly of the optical information medium. Use of the treated polycarbonate substrate in the optical information medium results in the medium exhibiting a high level of performance over an extended useful life.