PURPOSE: To improve the sensitivity of the title material against a semiconductor laser, and to lessen the change of the sensitivity of the material against the change of a wavelength by specifying the spectrally sensitive distribution of the material.

CONSTITUTION: The sensitive material is composed of the photosensitive material which exposes it using a light source capable of changing the max. wavelength of an emission spectrum by the variance of a temp. and the production of the material. The spectrally sensitive distribution of the material is specified to within 0.2 (log E) against the standard value of a light source of ±25nm, and is controlled to within the value by incorporating a prescribed sensitizing dye (such as a compd. shown by formula I) and a prescribed phenol resin or a compd. shown by formula II, in the material. In formula I, Y1 and Y2 are each an atomic group necessary for forming a prescribed ring, R1 and R2 are each a lower alkyl or alkyl group having sulfo group, etc., R3 is methyl or ethyl group, etc., X1 is an anion, (n1) and (n2) are each 1 or 2, (m) is 1 or 0. In formula II, A is an aromatic residual group, R1-R4 are each hydrogen atom or hydroxyl group, etc.