When photographic printing out or developing out paper is exposed to cathode rays in air (Lenard rays) for a sufficient time, it undergoes a color change similar to but not quite like that produced by exposure to light. It has been noted that, when a sample of the photographic paper is exposed to Cathode rays, it is rendered relatively insensitive to subsequent exposure to light. This peculiar effect is not observed when developing agents are used on the developing out paper, nor is it observed on blue print paper. Investigation indicates that the desensitizing effect of the cathode ray exposure can be simulated by application of heat, although the temperature to which the emulsion must be raised is surprisingly high. Experiments with other materials indicate that local temperatures in the rayed object may be very high. The importance of this finding has not been appreciated by those working in biological fields.
Proceedings of the Iowa Academy of Science
©1934 Iowa Academy of Science, Inc.
Carr, P. H.
"An Effect of Cathode Rays on Photographic Paper,"
Proceedings of the Iowa Academy of Science, 41(1), 248-249.
Available at: https://scholarworks.uni.edu/pias/vol41/iss1/76