The existence of reversible photosensitivity in some artificial materials containing rutile

Publisher Website
Google Scholar
Abstract
In 1934 a contribution from America (Parmelee and Badger, p. 2) reported that a certain glaze, containing rutile, showed rapid reversible darkening in daylight. It was stated that C. H. Zwermann, Jr., ascribed this photosensitivity to titanium. In the present author's experience the phenomenon is often exhibited, in varying degrees, by commercial glazes based on rutile or on the purified titanium dioxide available in industry, as well as by glazes made up in the laboratory from chemical titanium dioxide of high purity. Lee, also in America, observed reversible darkening in sunlight in commercial titanium dioxide itself, and the existence of this effect was confirmed by Williamson (1937) for some brands of commercial titanium dioxide available in Britain. These brands were affected by daylight which had passed through glass, and some tentative suggestions were made regarding the mechanism of the reversible darkening. Later it was demonstrated (Williamson, 1939) that reversible darkening in daylight could be produced in a sample of titanium dioxide of considerable purity, which was itself not discoloured by light, by contamination with iron according to a special method.

This publication has 10 references indexed in Scilit: