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. 12, 1988
Filed:
Jan. 16, 1986
Applicant:
Inventors:
Assignee:
Nitto Electric Industrial Co., Ltd., Osaka, JP;
Primary Examiner:
Int. Cl.
CPC ...
B01D / ;
U.S. Cl.
CPC ...
264 451 ; 21050037 ; 21050042 ; 427245 ; 427246 ;
Abstract
A composite semipermeable membrane and a process for preparation thereof are described, wherein said membrane comprises (1) a porous substrate, (2) an ultrathin film as a surface layer formed by polymerization by crosslinking of polyvinyl alcohol and an amino compound having at least two secondary amino groups using a polyfunctional crosslinking reagent capable of reacting with secondary amino groups and hydroxyl groups, and (3) a porous inner layer composed of water insoluble polyvinyl alcohol which is present between the porous substrate and the ultrathin film.