Polyurethane layer for a light directing article
US11567239B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 8, 2020 |
| Grant date | Jan 31, 2023 |
| Priority date | — |
| Expiry date | Jul 28, 2041 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2375/06
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The disclosed aliphatic thermoplastic polyurethane composition is well suited for use in thin, flexible light directing articles to impart flexibility, toughness, or protection to the light directing articles that contain optically active elements. The disclosed aliphatic thermoplastic polyurethanes have improved thermostability at higher temperatures. Specifically, the disclosed aliphatic thermoplastic polyurethanes have a cross-over temperature greater than 110° C. In one embodiment, the cross-over temperature is greater than 130° C. In one embodiment, the cross-over temperature is less than 170° C. and a Tg greater than 35° C. and less than 70° C.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.