US 2003/0145748 A1 · Supporting body for lithography block and original lithography block

Abstract

Objects of the present invention are to provide a positive working presensitized plate of a thermal type, which has damage resistance, and which is handled easily in conventional operation, high in sensitivity and excellent in press life when used as a lithographic printing plate, and to provide a support for a lithographic printing plate, which is suitably used for the same. The objects have been achieved by a support for a lithographic printing plate obtained by performing graining treatment, alkali etching treatment and anodizing treatment on an aluminum plate, wherein a ratio of a real area of a surface thereof to an apparent area of the surface set larger by 1.3 to 1.8 times, comprising a pit having an average diameter of 0.3 to 1.0 μm and a micro grained structure inside on the surface, wherein a ratio of an apparent area of the pits to the apparent area of the surface is 90% or more; and a presensitized plate comprising the support for a lithographic printing plate and a photosensitive layer that can become alkali-soluble by heating provided on the support.

Claims5

Dependent claims

A support for a lithographic printing plate obtained by performing graining treatment, alkali etching treatment and anodizing treatment on an aluminum plate,

wherein a ratio of a real area of a surface thereof to an apparent area of the surface set larger by 1.3 to 1.8 times,
comprising a pit having an average diameter of 0.3 to 1.0 μm and a micro grained structure inside on the surface,
wherein a ratio of an apparent area of the pits to the apparent area of the surface is 90% or more.

Dependencies are inferred from the claim text.

Supporting body for lithography block and original lithography block

Life of this patent

Supporting body for lithography block and original lithography block

Life of this patent

Abstract

Claims5