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. 05, 1995
Filed:
May. 25, 1994
Maki Itoh, Hadano, JP;
Dow Corning Corporation, Midland, MI (US);
Abstract
There is disclosed an organopolysiloxane having bifunctional biphenyl groups of the formula I ##STR1## wherein Q is selected from the group consisting of a nitro group, a substituted amino group and an unsubstituted amino group, Z is an organopolysiloxane group represented by the formula II ##STR2## in which R.sup.1 is a divalent organic group having at least 2 carbon atoms, R.sup.2 through R.sup.6 are the same or different monovalent organic groups, n is an integer having a value of at least 1 and m is 0 or 1. The above organopolysiloxane may be reacted with an aromatic tetracarboxylic acid dianhydride and, optionally, with an aromatic diamine to obtain a polyamide acid, which may then be subjected to a thermal imidization step to provide a polyimide having repeating units shown by the formulas VI and VII ##STR3## wherein A.sup.1 is a tetravalent aromatic group, A.sup.3 is a divalent aromatic group and A.sup.2 is a divalent organic group which contains a siloxane residue and wherein the molar ratio of repeating unit VI to repeating unit VII in the range 100:0 to 1:99.