| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for manufacturing a support for a lithographic printing plate by which it is possible to obtain a photosensitive lithographic printing plate capable of stably manufacturing high-quality print, a support for a lithographic printing plate, and a photosensitive lithographic printing plate. SOLUTION: This method for manufacturing a support for lithographic printing performs the electrolytic surface roughing treatment of an Al-size plate a few times in an acidic electrolyte with at least, two electrolytic cells using an alternating current waveform 1 whose polarity changes alternately. Further, the shape of an alternating current waveform to be used for at least, one electrolytic cell is made different from the shape of an alternating current waveform to be used for the other electrolytic cell. The method for manufacturing the support for lithographic printing is such that, after forming pits, each of which has an opening dia. of 2-30μm, the edge part of each of the pits may be selectively removed. In addition, the support for lithographic printing is of such a construction that the pits with an opening dia. of 0.2-0.8μm are overlapped among the pits having an opening dia. of 2-30μm and the edge parts of the pits with an opening dia. of 2-30μm are smooth. The photosensitive lithographic printing plate is formed by coating a photosensitive resin on the support for lithographic printing. |
