Sanyo-kokusaku Pulp Co., Ltd.

Hideaki Sasaki

Norio Yabe

Kuniaki Monden

Method of forming a positive-positive type image is disclosed, which is characterized in that a photosensitive layer is formed on a substrate using a composition comprising water-soluble photo-crosslinking agent, water-soluble resin and synthetic resin emulsion and further coloring agent, if necessary, said photosensitive layer is exposed to active rays through manuscript, then this is immersed into warm water of 30.degree. to 60.degree. C. for not less than 3 seconds to allow the exposed area to swell and soften sufficiently with warm water and simultaneously to allow almost all water-soluble photo-crosslinking agent in the nonexposed area to dissolve out into warm water, and successively the swollen and softened exposed area is rubbed out to form an image having no coloring originating from water-soluble photo-crosslinking agent without using the development chemicals except water.

Growing community of inventors

Moroyama, Japan

Hideaki Sasaki