| 摘要 |
There is described a method of forming a lithographic plate by the heat-mode imaging method which comprises coating on a base which can be used as a lithographic base, a positive working photosensitive composition which comprises a naphthoquinone diazide ester of a phenolic resin or a naphthoquinone diazide ester and a phenolic resin and at least one substance which absorbs infrared radiation, overall exposing the assembly to ultraviolet light to render the photosensitive composition developable, imaging the plate by means of a laser which emits in the infrared region of the spectrum and then developing the plate to remove those areas of the photosensitive composition not exposed to the laser. |
