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. 25, 1990
Filed:
Feb. 27, 1989
Applicant:
Inventors:
Hanns P Muller, Gladbach, DE;
Bernhard Jansen, Koeln, DE;
Wolfgang Calaminus, Bonn, DE;
Rolf Dhein, Krefeld, DE;
Assignee:
Bayer Aktiengesellschaft, Leverkusen, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C08G / ;
U.S. Cl.
CPC ...
528 26 ; 528196 ; 528209 ; 528288 ; 528300 ; 528370 ; 528372 ;
Abstract
Liquid crystalline bis-chlorocarbonic acid esters are 4-hydroxybenzoic acid-(4'-hydroxyphenyl) esters corresponding to the following formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 denote, independently of one another, hydrogen, a halogen atom or a C.sub.1 to C.sub.6 alkyl group. Preparation of (I) and liquid crystalline N-alkyl polyurethanes and polycarbonates prepared form (I) are other invention embodiments.