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:
Oct. 27, 2020
Filed:
Oct. 06, 2015
Toyobo Co., Ltd., Osaka-shi, Osaka, JP;
Takahito Nakao, Otsu, JP;
Mayumi Akashi, Otsu, JP;
Miyuki Yao, Otsu, JP;
Seiji Watanuki, Otsu, JP;
Tooru Kitagawa, Otsu, JP;
TOYOBO CO., LTD., Osaka-shi, Osaka, JP;
Abstract
[Problem] To provide a membrane for the forward osmosis method, which keeps a high porosity, reduces concentration polarization by appropriately controlling the pore distribution, achieves both high water permeability and a self-supporting property, and has high chemical durability such that are membrane is applicable to various draw solutions. [Solution] A separation membrane having a structure inclined from an outer surface side to an inner surface side, a ratio between a thickness of a dense layer having a dense polymer density and a thickness of a coarse layer having a coarse polymer density being in a range of 0.25≤(the thickness of the coarse layer)/[(the thickness of the dense layer)+(the thickness of the coarse layer)]≤0.6, when measuring polymer density distribution in a thickness direction of the separation membrane by Raman spectroscopy.