二色発光型記録紙

抄録

A new type of two-color thermal recording paper which develops black and red images under low temperature is described. The paper consists of only a single thermosensitive layer containing coupling agents, an organic base, a thermosensitizer and two kinds of diazonium salts encapsulated indivisually in microcapsules. Under the heat treatment, the two diazonium salts of A and B react with the coupling agents to develop green and red colors respectively. On the other hand, the former A, is decomposed by exposure to light of a wavelength of 420 nm and on contrary, the latter B, is not decomposed by the same treatment.
This noble thermal paper provides two color images with the following procedure; i) the first thermal processing develops a black image (green+red) prepared by A and B, ii) the exposure to light of a wavelength of 420 nm to decompose the diazonium salt A, iii) the second thermal processing to develop a red image in the non-black area.
This thermal recording paper has advantages of a high thermosensitivity to be suitable for the G3 facsimile equipment and a high resistance to such chemicals as those containing in sign pens, markers and mending tapes.