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. 02, 1985
Filed:
Nov. 22, 1983
Masaaki Todoko, Yamaguchi, JP;
Hiroyuki Watanabe, Yamaguchi, JP;
Toyo Soda Manufacturing Co., Ltd., Shinnanyo, JP;
Abstract
A process for producing cyclized isoprene polymers having a dispersion degree not higher than 2, which comprises living-polymerizing isoprene monomers using as initiator an organometal compound which is expressed by a general formula RM (where R is alkyl, aryl or aralkyl group and M is lithium, sodium or potassium atom), to obtain an isoprene polymer having a dispersion degree not larger than 1.1, which is close to a unit dispersion, and bringing the obtained polymer into contact with a catalyst composed of a boron trifluoride-ether complex and a carboxylic acid expressed by a general formula Cl.sub.3-n H.sub.n CCOOH (where n is an integer ranging from 0 to 3) under a mild condition. The cyclized polymer is very useful for negative resists in integrated circuits.