PURPOSE: To obtain the positive image having uniform and high quality and sufficient image density short developing time with less tendency for generating fog, without using a complex and expensive developing device by incorporating a specific compd. as a uncleus forming agent to a sensitive material.
CONSTITUTION: The compd. shown by formula I is used as a uncleus forming agent. In the formula, R21 is an aliphatic, an armoatic or a heterocuclic group, R22 is hydrogen atom, alkyl, aralkyl, aryl, alkoxy, aryloxy or amino group, G is carbonyl, sulfonyl, sulfoxy, phosphoryl group, R23 and R24 are each hydrogen atom or any one of them is hydrogen atom, another of which is alkylfulfonyl, arylsulfonyl or acyl group, G, R23 and R24 together with a hydrazine type nitrogen atom each may form a hydrazone structure. The groups as mentioned above may be substd.
HIRANO SHIGEO
DAIMATSU HIDEKI
