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:
Jun. 12, 1990
Filed:
Jul. 28, 1986
Jun Sasaki, Kanagawa, JP;
Kyoichi Naruo, Kanagawa, JP;
Fuji Photo Film Co., Ltd., Kanagawa, JP;
Abstract
A new micro-porous membrane having a layer of minimum pores inside is disclosed. This membrane can be produced by a kind of dry-wet method in which a gas is in contact with the surface of the spread solution before it is immersed in a solidifying bath to form a coacervation phase only in the surface layer of the spread solution. It is quite important to control the amount of non-solvent for a utilized polymer contained in the gas as well as a blowing rate of the gas toward the above mentioned surface. The micro-porous membrane of the present invention not only has an improved filtration flow rate and life as a filter, but also the risk of being damaged by scratches is minimized.