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. 05, 2025
Filed:
Dec. 21, 2020
Applicant:
Nof Corporation, Tokyo, JP;
Inventors:
Midori Hirai, Kawasaki, JP;
Kyu Takeuchi, Kawasaki, JP;
Assignee:
NOF CORPORATION, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C08G 65/30 (2006.01);
U.S. Cl.
CPC ...
C08G 65/30 (2013.01);
Abstract
A method for purifying a branched polyethylene glycol, which includes adding, to a branched polyethylene glycol compound represented by the following formula [1] and having a weight average molecular weight of 40,000 or more: where Z, Y, Y, A, Polymer, l, m and b are as defined herein, at least one solid acid selected from magnesium silicate, aluminum silicate, and aluminum magnesium silicate and having a specific surface area of 50 to 250 m/g in the presence of an aprotic organic solvent to obtain a mixture; stirring the mixture; and subsequently separating the solid acid.