PURPOSE: To provide an image forming device by which an image is formed on a plain paper by using a microcapsule containing at least an image source substance such as photosensitive silver halid, reducer, polymerized compound, and dye, pigment or dye precursor.

CONSTITUTION: In this image forming device 1, image exposure is performed to a photosensitive medium 33 where the microcapsule is carried. As soon as powder 22 consisting of a substance which contributes to forming the image in cooperation with the image source substance is applied to the photosensitive medium 33, the medium 33 is heated so as to form a chemical latent image. The photosensitive medium 33 and the plain paper 61 are pressured, and the image is formed on the plain paper 61.