Black and white direct positive image forming process

Year	Description
1992	Invention patented by Katsumi Hayashi on July 15th, 1992. Abstract: A black and white direct positive image forming process is disclosed. The process comprises imagewise exposing to light a silver halide light sensitive material and developing the material with a black and white developing solution. The light-sensitive material comprises a non-pre-fogged internal latent image type silver halide emulsion layer provided on a support. The material further contains a quaternary salt nucleating agent and a nucleating accelerator. In the present invention, the black and white developing solution contains an imidazole compound and a benzotriazole compound. The amount of the benzotriazole compound is preferably in the range of 0.1 to 10 wt.% of the amount of the imidazole compound. The black and white direct positive image is preferably formed on a computer output microfilm (COM).
Source: selected by the editor from original sources.

Invention: Black and white direct positive image forming process