| abstract |
The invention provides a method for manufacturing a lithographic printing plate, which comprises the following steps: an exposure step of exposing a lithographic printing plate precursor having an image recording layer on an aluminum support to light in an image form to form exposed portions and unexposed portions; and a developing step of supplying a specific developer to remove the unexposed portion, wherein the aluminum support includes an aluminum plate and an anodic oxide coating of aluminum disposed on the aluminum plate, the anodic oxide coating has micropores extending in a depth direction from a surface on a side opposite to the aluminum plate, the micropores are constituted by large-diameter holes extending from the surface of the anodic oxide coating to a specific position, and specific small-diameter holes communicating with bottoms of the large-diameter holes, an average diameter of the large-diameter holes at the surface of the anodic oxide coating is a specific value, and an average diameter of the small-diameter holes at the communicating position is 13nm or less. |