To obtain a photosensitive material using a prefogged direct positive emulsion improved in storage stability without sacrificing photographic characteristics, such as sensitivity, Dmax, Dmin, and gradation in the leg part, by incorporating a specified compound in the emulsion layer or an adjacent hydrophilic protective colloid layer.
The emulsion layer or is its adjacent hydrophilic protective colloid layer contains one of the compounds represented by formula I-IV. In formula I, each of R1-R3 is an alkyl, cycloalkyl, aryl, alkenyl, cycloalkenyl, or heterocyclic group; (m) is an integer; L is an m-valent organic group combining through its carbon atom with P atom; (n) is 1, 2, or 3; and X is an n-valent anion, and in formulae II-IV, A is an organic group necessary to complete hetero ring; each of B and C is a divalent group; each of R1 and R2 is an alkyl or aryl group; each of R3 and R4 is H atom or a substituent; R5 is an alkyl group; and X is an anion.
NISHIYAMA SHINGO
INOUE NOBUAKI
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