Black and white photothermographic material

#This application claims priority under 35 USC 119 from Japanese Patent Application No. 2006-263432, the disclosure of which is incorporated by reference herein.

#1. Field of the Invention

#The present invention relates to a black and white photothermographic material. More particularly, the invention relates to a black and white photothermographic material which exhibits excellent image tone, excellent raw stock storage stability, and excellent image storage stability.

#An object of the present invention is to provide a black and white photothermographic material which exhibits favorable image tone and excellent storage stability.

#By means of adjusting color tone of a developed silver image by adding a color image to the developed silver image, the present invention makes it possible to provide a material that produces an image rapidly with high sensitivity and favorable color tone, which could not be realized in conventional image formation by developed silver only. The combined use of a color image with an image of developed silver, which is comprised as the main component, has been proposed conventionally. However, it has been difficult for the image of developed silver and the color image to attain uniform color tone balance across the overall image density area from a low density area to a maximum density area. Moreover, because of low color forming efficiency, it is necessary to use components for forming color such as a color developing agent, coupler, and the like in a large amount, so that it is found that there are other problems in that color tone is deteriorated after long storage before use even if the photothermographic material exhibits favorable performance just after the production thereof, and components for forming color which exist after image formation cause change in color tone, occurrence of stain, or the like.

#The present inventors have intensively researched means for solving the problems described above and found that the problems can be solved by using the reducing agent having a specific structure of the present invention as a reducing agent for silver ions forming a silver image, whereby they arrived at the present invention. In particular, in the case of a configuration in which plural image forming layers comprising an image forming layer forming a silver image and, adjacent to the image forming layer, an image forming layer which includes a coupler and forms a color image are provided, the present inventors have found that the above constitution is effective.