Envelope closure seal and method
US4932791A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 11, 1989 |
| Grant date | Jun 12, 1990 |
| Priority date | — |
| Expiry date | May 11, 2009 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB65D75/5805
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A closure seal and method for envelopes having front and back panels joined along bottom and side edges and in which a release liner strip delimits overlying marginal edges along the top of the panels. The liner strip initially covers a pressure sensitive adhesive band in the top marginal edge of one of the panels and extends through the side edge junctures of the panels to enable removal of the liner strip and securement of the top margins by the pressure sensitive adhesive band. Registered lines of perforations are formed across the top portion of both panels below the bottom edge of the release liner strip to define a tear line for opening the envelope after it has been sealed in embodiments not intended for liquid contents. The lines of perforations are omitted in a liquid containing envelope embodiment wherein the adhesive band joins with fused side edges of the envelope.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.