AUTOMATIC PRINTING PLATE EXPOSURE DEVICE AND PRINTING PLATE EXPOSURE METHOD

摘要

PROBLEM TO BE SOLVED: To obtain an automatic printing plate exposure device and a printing plate exposure method capable of preventing the occurrence of an image defect, such as out of focus, when an image is exposed to a printing plate. SOLUTION: A suction hole is formed at a surface plate 110 of the automatic printing plate exposure device 100 and a vacuum pump 306 is communicated with the suction hole. A communicating path 304 between the suction hole and the vacuum pump 306 is provided with a solenoid valve 308 and the communicating path 304 between the solenoid valve 308 and the vacuum pump 206 is provided with a chamber 310. A photopolymer plate 102 is placed atop the surface plate 110 and the solenoid valve 308 is once closed and the vacuum pump 306 is operated, by which the pressure in the reduced pressure space of the chamber 310 is reduced to a prescribed value or below. The solenoid valve 308 is instantaneously fully opened in this state and the reduced pressure space sucks the air with strong suction force at a time. The curled photopolymer plate 102 may therefore be completely brought into tight contact with the top surface of the surface plate 110 and the image defect, such as the out of focus, in exposing the image may be prevented.