Image Number 2 for United States Patent #7320826.
Described are photochromic articles that include a substrate, a temperature dependent reducing amount of at least one organic photochromic material (b) that changes from more absorbing to less absorbing of radiation in its activating spectral absorbance as the temperature increases from 10.degree. C. to 35.degree. C. and at least one other photochromic material (c) that is different from photochromic material (b). In the article, photochromic material (b) is interposed between photochromic material (c) and a source of activating radiation. The photochromic article demonstrates a more consistent photochromic response, for example, an optical density response loss of 50 percent or less over a temperature range of from 10.degree. C. to 35.degree. C. as measured in the Photochromic Temperature Dependence Test. Methods for producing the aforedescribed articles are also disclosed.