| abstract |
(57) [Summary] [Problem] It is possible to mount directly on a printing machine without exposure and print after exposure, and to improve sensitivity. Provided is a heat-sensitive lithographic printing original plate using an aluminum plate as a support. SOLUTION: An aluminum support is provided with an ink receiving layer and at least one element selected from beryllium, magnesium, aluminum, silicon, titanium, boron, germanium, tin, zirconium, iron, vanadium, antimony and transition metals. A hydrophilic layer containing a colloidal particulate oxide or hydroxide of at least one of the above, wherein at least one of the ink receiving layer and the hydrophilic layer contains a photothermal conversion agent, and the aluminum support is 2 g / m 2. A heat-sensitive lithographic printing plate having the above anodic oxide film and being subjected to a sealing treatment with a sealing ratio of 50% or more. |