Asahi Kasei Kogyo Kabushiki Kaisha

Yoshinobu Ito

Minoru Akiyama

Takeo Kimura

Tetsuo Shiga

Kageyasu Akashi

Takeki Matsui

Toshiyuki Iwaisako

Shozo Kinoshita

Masatsugu Yoshino

Tadao Matsushika

Hiroshi Naka

Hiroshi Takano

Hisao Yomogida

Naomi Yamaguchi

Tetsuo Siga

A post-activation type dry image forming material comprising (I) a silver salt component reducible to free silver upon light exposure and including silver iodide; (II) a redox reactive composition capable of making a visual change by a redox reaction of said composition, said reaction being initiated by heating in the presence of free silver; (III) an oxidizing agent for free silver which has an oxidizing capacity for free silver but is rendered photosensitive by heating and which, upon light exposure after said heating, is suppressed with respect to the oxidizing capacity for free silver and capable of catalytically promoting the redox reaction of said composition; and (IV) a photoreactive oxidizing agent, upon light exposure, capable of returning the reduced oxidizing agent for free silver to the original state. A post-activation type dry image forming material which is extremely excellent in stability of the raw image forming material, that is, can be stored in a light room for a time as long as a period of the order of years and which has high sensitivity can, for the first time, be realized by the ingenious combination of components. The effect of the interaction between the components, especially between the components (I), (III) and (IV) is noticeable in imparting to the present image forming material an extremely high stability of the raw image forming material.

Post-activation type dry image forming material

A novel heat-activatable and heat-developable dry image forming material comprising (a) a silver salt of long chain fatty acid with at least 16 carbon atoms, (b) a reducing agent for silver ions, (c) a silver halide component including silver iodide or a silver halide-forming component including silver iodide-forming compound, (d) an oxidizing agent for free silver, (e) a photoreactive halogeno oxidizing agent, (f) a binder, and (g) a specific spectral sensitizing dye has been found to have improved spectral sensitivity as well as excellent storage stability.

A novel dry image forming material comprising (a) a non-photosensitive organic silver salt oxidizing agent, (b) a reducing agent for silver ions, (c) a photosensitive silver halide or a photosensitive silver halide-forming component capable of forming a photosensitive silver halide by the reaction thereof with said organic silver salt oxidizing agent, and (d) a substituted 3-pyrazolin-5-one. The dry image forming material has improved sensitivity and storage stability of the raw image forming material and can form thereon an excellent black tone image.

Dry image forming material

Pseudo-boehmite having a bulk density of about 0.05 to 0.2 g/cc, an oil absorption of about 2.5 to 6.0 cc/g, a pore volume of about 2.0 to 7.0 cc/g over a pore diameter range of 176.mu. to 0.0035.mu. and a specific surface area of about 200 to 500 m.sup.2 /g, and a process for producing the same; useful as a filler, an absorbent, a catalyst, a filtering agent and a base material for composites; prepared by mixing alkali aluminate and halohydrin together at a low temperature, heating for reaction the resulting mixture, cooling the reacting solution, separating the resulting precipitate by filtration and, if desired subjecting the precipitate to washing with an organic solvent followed by drying.

Process for producing pseudo-boehmite

A novel non-silver salt type photosensitive composition which comprises (A) N,N'-diphenyl-p-phenylenediamine as a color developing agent and tetramethylthiuram disulfide which unexpectedly functions rather as another color developing agent than as a storage stabilizer, (B) an organic halide compound as a photoactivator, (C) a salicylic acid derivative as a storage stabilizer for an unexposed photosensitive material, (D) thiourea which functions rather as an agent capable of functioning as both an anti-foggant at and after image formation and a contrasting agent than as a storage stabilizer, and (E) at least one member selected from the group consisting of (i) 2-methylindole, (ii) 2-mercaptothiazoline and (iii) p-diethylaminobenzaldehyde as a color tone adjusting agent. A photosensitive material or film obtained from the present photosensitive composition has an excellent storage stability in the unexposed state, and can give, only by dry process, a blackish brown image having a high photographic density and a high contrast, with fog occurrence reduced.

Non-silver salt type photosensitive composition

Growing community of inventors

Fuji, Japan

Yoshinobu Ito