Process for making film
US5068070A · kind A · utility
7Cited by
7References
5Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 2, 1989 |
| Grant date | Nov 26, 1991 |
| Priority date | — |
| Expiry date | Oct 2, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S264/47
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A process for making a film including forming a composite material of a thermoplastic film into an annular original film having at least two thick portions according to the inflation process, making the annular original film into a flat shape such that the thick portions are located at substantially opposite ends thereof, and stretching the flat annular original film by clamping the thick portions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.