| 摘要 |
PROBLEM TO BE SOLVED: To improve printing contamination which is a failure caused by an ink of a ball-point pen remaining on the plate, by specifying the ratio of the period for washing to the period after completion of development till initiation of washing. SOLUTION: A photosensitive lithographic printing plate is treated in automatic developing machines 1 to 3 each by passing through a developing zone A, a carrying zone B from the developing zone to a washing zone, a washing zone C, a carrying zone D from the washing zone to a coating zone of a gum liquid, a containing zone E of a gum liquid, a carrying zone F from the coating zone of a gum liquid to a drying zone, and a drying zone G. In this automatic developing machine, washing time W means the period necessary for the top of the developed lithographic printing plate to pass through the washing zone C, and carrying time D means the period necessary for the top of the developed lithographic printing plate to pass through the carrying zone B from the developing zone to the washing zone. The ratio W/D of the washing time W to carrying time D is controlled to >=3. |
