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:
Jan. 17, 2012
Filed:
Mar. 31, 2010
Shuichi Yoshimura, Kanagawa, JP;
Ken-ichiro Nakamoto, Kanagawa, JP;
Chika Itoh, Kawasaki, JP;
NOF Corporation, Tokyo, JP;
Abstract
A purification method in which, from a specific polyoxyalkylene derivative having a molecular weight of 8,800 to 100,000, an impurity differing in the number of hydroxyl groups is separated, the method including steps (A), (B), (C), and (D). Step (A): a step in which an aprotic organic solvent is used in an amount at least 5 times by weight the amount of the polyoxyalkylene derivative to dissolve the polyoxyalkylene derivative therein and give a solution; step (B): a step in which an adsorbent comprising an oxide containing at least one of aluminum and silicon is added to the solution in an amount 0.5 to 5 times by weight the amount of the polyoxyalkylene derivative to thereby yield a slurry; step (C): a step in which the slurry is stirred at 25° C. or higher; step (D): a step in which the polyoxyalkylene derivative is recovered from the slurry.