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. 17, 1989
Filed:
Sep. 26, 1988
Applicant:
Inventors:
C C Chau, Midland, MI (US);
Jang-hi Im, Midland, MI (US);
Assignee:
The Dow Chemical Company, Midland, MI (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B29C / ; B29C / ; B29C / ; B32B / ;
U.S. Cl.
CPC ...
264 49 ; 264126 ; 264141 ; 264171 ; 26421112 ; 264320 ; 26433113 ; 26433117 ; 264344 ;
Abstract
A method for preparing porous membranes containing a homogeneous microporous structure and narrow pore size distribution which are useful for ultrafiltration, distillation and substrates for composite membranes, including preparing films, pellets or sheets containing alternating microlayers of high density polyethylene and polystyrene, recoextruding these films, pellets or sheets, pulverizing into fine granules or powder, compression molding or sintering into thin films, immersing these films in a solvent bath into which one component is selectively dissolved and separating the resultant porous membrane from the solvent.