PURPOSE: To improve color forming properties and the stability of a developed color image by containing an electron donating leuco dye and a salicylic acid derivative wherein a 6-position is substituted with an alkyl group and a 3-position is substituted with a group having no hydrogen atoms at an α-position or a metal salt thereof.
CONSTITUTION: An electron donating leuco dye and a salicylic acid derivative wherein a 6-position is substituted with an alkyl group and a 3-position is substituted with a group having no hydrogen atom at an α-position or a metal salt are contained. The pref. salicylic acid derivative is represented by formula (wherein R1 is an alkyl group, R2 is an alkyl group, X is an alkyl group and Y is an alkyl group or an aryl group. Among substituents represented by R1 and R2, a 1-8C alkyl group is pref. and X is pref. a 1-4 alkyl group and Y is pref. a 1-9 C alkyl group or a 6-24 aryl group). As the metal salt of the salicylic acid derivative, a zinc salt, an aluminum salt, a magnesium salt, a calcium salt, a sodium salt and a nickel salt are pref.
IWAKURA KEN
ITOU KORENARI
SATOMURA MASATO
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