LITHOGRAPHIC PRINTING PLATE SUPPORT, LITHOGRAPHIC PRINTING PLATE SUPPORT MANUFACTURING METHOD AND LITHOGRAPHIC PRINTING PLATE MASTER

摘要

The purpose of the invention is to provide a lithographic printing plate support of excellent scratch resistance with which a lithographic printing plate master, which has excellent printing durability when made into a lithographic printing plate and exhibits excellent on-board developability and does not generate dot-shaped contamination even when stored over long periods, can be obtained. This lighographic printing plate support is provided with an aluminum plate and an aluminum anodized film thereon. The anodized film has micropores that extend in the depth direction from the surface opposite the aluminum plate. Said micropores are configured from a large diameter pore section, which has a specific shape, and a small diameter pore section, which communicates with the bottom of the large diameter pore section and has a specific shape. At least a portion of the inside of the small diameter pore section is sealed by protrusions obtained from boehmite. The ratio of the mean height of boehmite protrusions on the inside of the large diameter pore section to the mean diameter of the anodized film surface of the large diameter pore section is a specific value or less.