Photochromic articles that activate behind ultraviolet radiation blocking transparencies and methods for preparation
申请人:——
公开号:US20040185268A1
公开(公告)日:2004-09-23
Described are photochromic articles that include a substrate and at least one photochromic material 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.