Method for preparing a microporous film
US5158636A · kind A · utility
33Cited by
5References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 27, 1989 |
| Grant date | Oct 27, 1992 |
| Priority date | — |
| Expiry date | Feb 27, 2009 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2201/05
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A microporous, polymeric film is prepared by dissolving methylene-chloride-soluble, film-forming polymers completely in methylene chloride. Then an aqueous phase is prepared containing non-methylene-chloride-soluble, water-soluble thickeners and, if desired, additives, and brought to a viscosity of about 0.07 to 0.5 Pa s. The aqueous phase is then dispersed in the polymer solution and the resultant paste is spread onto a support material or intermediate support, the methylene chloride is evaporated, the resultant membrane is transferred to the actual support, and finally the water is removed by drying.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.