Fluoroplastic apertured film fabric, structures employing same and method of making same
US5776343A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 3, 1995 |
| Grant date | Jul 7, 1998 |
| Priority date | — |
| Expiry date | Aug 3, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T156/1041
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
An apertured film extruded from a crystalline, thermoplastic, extrudable fluoroplastic material. The film includes spaced-apart strand segments defining apertures therebetween and has at least 10 strand segments per inch. The film has a thickness of 2-12 mils and a Frazier air permeability number in the range of 200-2,000. The invention includes a process for preparing an apertured thermoplastic film by a single-sided embossing method. The process includes the steps of extruding in the machine direction, a film of a molten, crystalline, thermoplastic, extrudable, fluoroplastic material. The molten extruded film is passed in the machine direction through the nip of two metal rollers. One of the rollers has a substantially smooth surface, having a convex configuration as viewed from a direction substantially parallel to the axis of the roll, such that the diameter in the center of the roll is in the range of 8-12 mils greater than the diameter at the ends of the roller for a 40 inch roller. The other roller includes a plurality of discrete, raised projections disposed in a pattern. Each of the projections terminates in a distal end. The ends are separated from each other and are comp…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.