Method of making apertured films and net like fabrics
US4842794A · kind A · utility
96Cited by
29References
23Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 30, 1987 |
| Grant date | Jun 27, 1989 |
| Priority date | — |
| Expiry date | Jul 30, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S264/81
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A method of making apertured films including the step of perforating films of thermoplastic materials with embossing rolls engraved with patterns which form small slits or incipient slits in the sheet. The patterns are such that the design on the roll includes lands, or raised areas, which cross lands of the opposing roll at an acute angle. The perforated or partially perforated film formed may then be further processed by orientation, uniaxial or biaxial, simultaneous or sequential; by heat treatment; or both to modify the porosity, hole size, or other properties as desired.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.