Porpous PTFE film and a manufacturing method therefor
US5476589A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 10, 1995 |
| Grant date | Dec 19, 1995 |
| Priority date | — |
| Expiry date | Mar 10, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2327/18
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A nonwoven web is described that is a thin porous polytetrafluoroethylene membrane consisting essentially of a nonwoven web having a microstructure of substantially only microfibrils fused at crossover points. It is usually strong, is unusually thin, has unusually small pore sizes, but a very high air flow-through. It has a pore size between 0.05 and 0.4 micrometers; a bubble point between 10 and 60 psi; a pore size distribution value between 1.05 and 1.20; a ball burst strength between 0.9 and 17 pounds/force; an air flow of between 20 Frazier and 10 Gurley seconds; a thickness between 1.0-25.4 micrometer; and a fiber diameter ranging between 5 and 200 nm.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.