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:
Aug. 25, 1981
Filed:
Jul. 16, 1979
Ciba-Geigy Corporation, Ardsley, NY (US);
Abstract
Novel carboxylic acid dianhydrides are obtained by esterifying or trans-esterifying hydantoindiols, or diesters thereof, of the formula ##STR1## in which m and n are each a number from 1 to 4 and R.sub.1 and R.sub.2 are each an alkyl having 1 to 5 C atoms, or R.sub.1 and R.sub.2 together are the pentamethylene radical, R.sub.3 is a hydrogen atom or methyl and R.sub.4 is a hydrogen atom, acetyl or propionyl, with trimellitic anhydride. The novel dianhydrides are valuable curing agents for epoxide resins and are suitable for the preparation of polymers which are derived from carboxylic acid dianhydrides.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile