Method of film crease elimination and patch bag without crease within lay-flat bag side
US6296886A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 17, 1997 |
| Grant date | Oct 2, 2001 |
| Priority date | — |
| Expiry date | Mar 17, 2017 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB31B70/876
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A process for removing creases from a film eliminates a problem in the quality of the heat seal for a patch bag having at least a segment of one or more bag side edges (or the bag bottom edge) covered by one or more patches. The film creases are removed by inflating the film tubing which is later converted to a bag, heating regions containing the creases with a heating means to a temperature which, in combination with the pressure within the inflated tubing, causes the creases to relax. The heated crease-containing regions are then cooled and the inflated tubing is deflated and wound up in a new configuration in which at least one patch covers at least one side edge or the bottom edge.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.