Heat-sensitive treatment-free planographic printing plate material containing thermosensitive protection layer and application thereof

A heat-sensitive treatment-free planographic printing plate material, wherein:

• the planographic printing plate material sequentially comprises a supporting body, a hydrophilic layer, a heat-sensitive layer and a thermosensitive protection layer from bottom to top;
• the thermosensitive protection layer comprises 40-90 parts of water-soluble resin, 10-60 parts of hydrophilic cross-linking agent and 1-30 parts of acid-producing agent;
• the heat-sensitive layer comprises the following components in parts by weight:
• 10-60 parts of film-forming resin,
• 30-90 parts of cross-linking agent,
• 0-40 parts of diluting agent,
• 1-30 parts of polymerization initiator,
• 1-10 parts of infrared absorbing dye, and
• 0.1-10 parts of coloring background dye;
• the hydrophilic layer comprises water-soluble resin, and the dry coating weight of the hydrophilic layer on the supporting body is 0.001-0.1 g/m2;
• and
• the film-forming resin in the heat-sensitive layer is one or more of oil-soluble polymer with a weight-average molecular weight of 20000-100000 and water-oil-soluble polymer with a weight-average molecular weight of 10000-200000.