Patent ID: 7604923

Claim:
An image forming method comprising: scanning exposing an image forming material having a photosensitive layer comprising an infrared absorbing agent, a polymerization initiator and a polymerizable compound on a substrate to infrared beams from a light source so that the distance between centers of the infrared beams in the sub-scanning direction is smaller than the beam diameter of each of the infrared beams, the solubility of the photosensitive layer in an alkali developing solution being reduced upon exposure to light of wavelengths in the range of 750 nm to 1400 nm; and forming an image by developing the exposed image forming material, wherein the imagewise light exposure is carried out under conditions where the infrared beam diameter is 20 μm or less, and the overlapping coefficient, which is the ratio of the full-width half-maximum (FWHM) of the infrared beam diameter to the distance between beam centers in the sub-scanning direction, is in the range of 0.8 to 4.