PURPOSE: To improve printing resistance and to reduce the number of wasteful copies at the time of the printing process startup by adjusting hardening on the photosensitive side of an image forming element so that the time required for completely resolving a surface layer, a photosensitive layer and a base layer by using NaOCl is in a specific range.

CONSTITUTION: The image forming element is constituted by including the photosensitive layer contng. the base layer and a silver halide emulsion on the same side of the supporting body and the surface layer contng. a physical development nucleous in this order. Further, the image forming element is constituted by including gelatin in which the base layer and/or the photosensitive layer are hardened with a divinylsulfonyl hardner so that the time required for completely resolving the photosensitive layer and the surface layer by using a 0.14wt.% of aqueous solution of NaOCl is in the range of 1000 to 1600 seconds. The image forming element in accordance therewith is exposed in conformity of the image, and next, the image forming element obtained in such a manner and exposed in conformity of the image is developed with an alkaline processing solution in the presence of a developer and a silver halide solvent.