Transparent polyurethane compositions
US6458875B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 1, 2000 |
| Grant date | Oct 1, 2002 |
| Priority date | — |
| Expiry date | Aug 19, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31601
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The present invention is embodied in a polyurethane composition suitable for coating, casting or laminating, which incorporates a prescribed additive selected to increase the composition's electrical conductivity without adversely affecting the composition's transparency and percent haze and without adversely affecting its adhesion to an underlying substrate or its environmental durability, especially with regard to humidity resistance. The prescribed additive is an ionizable metal salt of a perfluoroalkylsulfonimide, in a weight percent of 0.5 to 5.0, with the metal being an alkali metal and the preferred perfluoroalkylsulfonimide being trifluoromethanesulfonimide. The most preferred salt is lithium trifluoromethanesulfonimide. The preferred polyurethanes include both aliphatic polyetherurethanes and aliphatic polyesterurethanes. Use of the additive enhances the composition's electrical conductivity by at least about two orders of magnitude, thereby minimizing the risk of a static charge building to a point where a shock hazard is created or the polyurethane coating or laminate is damaged by a rapid discharge of electrical current. The composition is particularly useful in an airc…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.