Patent ID: 7214469

Claim:
A lithographic printing plate precursor comprising: a support; and an image recording layer capable of being removed by a printing ink and/or a fountain solution, in which the image recording layer comprises: an infrared absorber; a microcapsule; an addition polymerizable compound having at least one terminal ethylenically unsaturated bond, said polymerizable compound being located outside of the microcapsule; and a graft polymer having a graft chain containing a hydrophilic segment, wherein the hydrophilic segment is a polymer containing at least one monomer unit selected from the group consisting of an amido group-containing monomer, an acid group-containing monomer, an alkali metal salt of an acid group-containing monomer, a quaternary ammonium salt-containing monomer and a hydroxyl group-containing monomer in proportion of 50 mol % or more, wherein said image recording layer is formed directly on said support or is formed directly on a heat-insulating undercoating layer formed directly on said support.