Extruded zipper with orienting means and method for orienting same
US5566429A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 19, 1994 |
| Grant date | Oct 22, 1996 |
| Priority date | — |
| Expiry date | Oct 19, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T24/45168
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A string zipper is provided for use in the manufacture of material for reclosable plastic bags. The string zipper includes a first profile and a complementary mating profile which, when interlocked and properly attached to the bag walls render the bag easy to open from the outside and hard to open from the inside. One of the profiles is formed of polyethylene material that includes an optical brightener to facilitate properly orienting the zipper on a sheet of plastic material. During manufacture of plastic bag material, the zipper is passed through a black light so that the profile containing the brightener can be detected and thus the profiles may readily be distinguished from one another and properly oriented on the sheet material to obtain the desired force differential feature on the final bag.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.