Method for die cutting a plastic web
US4218497A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 21, 1979 |
| Grant date | Aug 19, 1980 |
| Priority date | — |
| Expiry date | May 21, 1999 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB26D2007/202
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
An improved method for die cutting a plastic or paper web which is used in the formation of the trays, pouches and such composite structures for containing food or other consumable products, or is used in the formation of hospital or medical products, for instance filters employed in medical procedures, is effective to provide smooth cut edges of the tray without any hair-like sliver members. In the process where a rotary die cutter is employed and includes a support member for supporting the web to be cut, a frangible but non-splintered coating is first applied to the surface of the web coming in contact with the support member. The web is conveyed between the rotatable die cutter and the support member and the die cutter cuts the web by penetrating the entire thickness thereof, however, the cutter blade does not come in contact with the support member. The impact of the die cutter blade causes a crack in the coating such that separation of the cut portions of the web is effected along the crack by the shearing action caused by the movement of the web. The resulting cut edge of the finished plastic or paper product is smooth, and does not include any hair-like slivers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.