Linerless postage stamps with cancellation ink absorbing particles
US6203067A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 4, 1998 |
| Grant date | Mar 20, 2001 |
| Priority date | — |
| Expiry date | Dec 4, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09F3/10
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Linerless postage stamps are produced by coating a paper substrate on the bottom surface with pressure sensitive adhesive, and coating the substrate on the top surface with release material, such as silicone, which includes an effective amount of stamp cancellation ink retaining particles, so that when the release coat and particles are contacted by stamp cancellation ink the particles will retain sufficient stamp cancellation ink so that the ink is visible on the top face and will not be wiped off during normal handling. The particles may comprise fumed silica, colloidal silica, kaolin clay, aluminum oxide, wollastonite, talc, calcium carbonate, titanium dioxide, or combinations thereof. Stamp indicia is typically provided on the top of the substrate underneath the release coat.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.