Method for producing microporous sheet
US8388878B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 31, 2008 |
| Grant date | Mar 5, 2013 |
| Priority date | — |
| Expiry date | Feb 22, 2030 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/249978
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Provided is a method of producing a microporous sheet material of a polymeric matrix of polyolefin, with finely divided and substantially water-insoluble filler distributed throughout the matrix, and a network of interconnecting pores communicating throughout the microporous material. The method includes: (a) forming a mixture of polyolefin, filler and a processing plasticizer composition; (b) extruding the mixture to form a continuous sheet; and (c) contacting the continuous sheet with a non-flammable extraction fluid composition to extract the processing plasticizer composition from the continuous sheet. The extraction fluid has a boiling point of 75° C. or less, and is essentially free of trichloroethylene. The microporous sheet material has Tensile Strength equal to or greater than 800 kPa. A microporous sheet material also is provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.