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:
Dec. 29, 1992
Filed:
Jun. 04, 1990
Applicant:
Inventors:
C Richard Costin, West Chester, PA (US);
Thomas W Hazell, Swarthmore, PA (US);
Gary W Ceska, West Chester, PA (US);
James P Horgan, West Chester, PA (US);
Assignee:
Sartomer Company, Inc., Exton, PA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C08F / ;
U.S. Cl.
CPC ...
528487 ; 528495 ; 528497 ;
Abstract
The residual level of N-vinylcarbazole in polyvinylcarbazole has been reduced to an amount less than 25 ppm by treatment of a solution of the polyvinylcarbazole with a strong acid. The polymer can be recovered in pure form by precipitation of the polymer from solution with a non-solvent.