Method of printing through contact exposure in step-and-repeat machine

Abstract

Disclosed is a method of printing through a contact exposure in a step-and-repeat machine which is constituted by a photosensitive material holder for supporting a photosensitive material, an original film holder having a transparent base plate for fixedly holding an original film and having a holder frame defining a first chamber between the photosensitive material holder and the base plate, first suction means for holding the original film on the base plate, second suction means for evacuating air within the first chamber, and a light source disposed behind the original film for exposing the photosensitive material through the original film. The method comprises the steps of: actuating the first suction means to mount the original film fixedly on the base plate of the original holder by means of suction: positioning the original holder at a desired position on the photosensitive material; actuating the second suction means to evacuate air within the first chamber; decreasing the suction applied from the first suction means so as to effect the higher negative pressure within the first chamber than that applied by the first suction means, by which the original film contacts with the photosensitive material; and exposing the photosensitive material through the original film.

Dependencies are inferred from the claim text.