Method of stretching film
US7037461B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 21, 1999 |
| Grant date | May 2, 2006 |
| Priority date | — |
| Expiry date | Dec 21, 2019 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C55/165
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A method of stretching films in which all or a portion of the width of the film is cooled during or just after stretching so as to improve the uniformity of the film. The includes stretching a polymeric film in a tenter that grasps the film with a plurality of clips along the opposing edges of the film and propels the clips to thereby stretch the film. The tenter includes driven clips and idler clips, with at least one idler clip between respective pairs of driven clips. The cooling is done so as to improve the uniformity of the clip spacing relative to the spacing obtained at otherwise identical process conditions without such cooling.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.