| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an infrared-sensitive positive planographic printing plate having high sensitivity and capable of recording with an infrared laser. <P>SOLUTION: The planographic printing plate includes on a hydrophilic support a multilayer type photosensitive layer formed by sequentially stacking a first layer containing a water-insoluble and alkali-soluble resin and an infrared absorbent, and an uppermost layer containing a water-insoluble and alkali-soluble resin and an infrared absorbent and having solubility in an alkaline aqueous solution increased by exposure. In the planographic printing plate, the difference between a wavelength at a maximum degree of fluorescence of the infrared absorbent in the first layer and a wavelength at a maximum absorbance of the infrared absorbent in the uppermost layer, or the difference between a wavelength at a maximum degree of fluorescence of the infrared absorbent in the uppermost layer and a wavelength at a maximum absorbance of the infrared absorbent in the first layer is 0-30 nm. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
