Isomerization behavior of fulgide-type photochromic compounds upon X-ray irradiation

We fabricated poly(methyl methacrylate)-besed films containing Aberchrome 670 (Ab670) and investigated the isomerization behavior of the Ab670 upon X-ray irradiation with the aim of developing a tissue-equivalent and non-disposable radiation imaging element. The effect of the addition of the organic phosphor 2-(4-tert-butylphenyl)-5-(4-biphenylyl)-1,3,4-oxadiazole was also studied. The absorption peak around 520 nm increased upon UV irradiation and that around 490 nm increased upon X-ray irradiation, while an additional irreversible reaction was also observed. These results suggest that the photochromic reaction and the other reaction proceeded simultaneously, triggered by X-ray irradiation.