Photochromic articles that activate behind ultraviolet radiation blocking transparencies and methods for preparation
US7166357B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 20, 2003 |
| Grant date | Jan 23, 2007 |
| Priority date | — |
| Expiry date | Mar 28, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31993
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Described are photochromic articles that include a substrate and a photochromic amount of at least one organic photochromic material (b) represented by graphic formula XIII adapted to change from an unactivated state to an activated state by exposure to radiation substantially in a wavelength range from 380 to 410 nanometers (nm) when measured over a wavelength range of from 380 to 700 nm. The photochromic articles demonstrate a photochromic response when activated behind an ultraviolet blocking transparency such as an automotive windshield. For example, the photochromic articles retain at least 12 percent of the activation measured as change in optical density or delta OD under outdoor simulating conditions in the Outdoor Test when tested under conditions simulating an eyeglass wearer behind an automotive windshield in the Behind the Windshield Test. Methods for producing the aforedescribed photochromic articles are also described.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.