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:
Nov. 08, 2011
Filed:
Dec. 19, 2003
Kazuaki Okabe, Kanagawa, JP;
Hiroshi Nakaoka, Kanagawa, JP;
Ikuhiko Kanehira, Yamaguchi, JP;
Hodogaya Chemical Co., Ltd., Kawasaki-shi, JP;
Abstract
A method for producing a polyether-polyol having a narrow molecular weight distribution, which comprises carrying out selective fractional extraction of the low-molecular weight component from a polyether-polyol (A) having an average molecular weight of from 500 to 4500 represented by formula (1):HO—[(CH)O]—[(CRR)O]—H  (1)wherein Rand R, which may be the same or different, each represents a hydrogen atom or a linear or branched alkyl group having from 1 to 5 carbon atoms; n indicates a positive integer; p indicates an integer of from 1 to 8; and q indicates 0 or a positive integer, by the use of an aqueous solution (C) containing from 15 to 70 wt % sulfuric acid at a room temperature to 100° C., to thereby suitably determine the amount of the aqueous sulfuric acid solution to the overall organic layer and the sulfuric acid concentration in accordance with the molecular weight and molecular weight distribution of the intended polyether-polyol to be fractionally extracted.