Abstract:
A lithographic printing plate precursor includes at least a white substrate and an image-recording layer, the white substrate has a reflection density of 0.25 or less at a side having the image-recording layer, and the image-recording layer contains an infrared absorbing agent, an onium salt polymerization initiator, a polymerizable compound and a color-forming compound and is capable of being removed with at least any one of printing ink and dampening water.
Abstract:
Provided are an on-press development type lithographic printing plate precursor having a support and an image-recording layer on the support in which the image-recording layer contains a coloring compound capable of having a coloring reaction with a decomposition product generated by exposure of the image-recording layer, and an on-press development type lithographic printing plate precursor having a support and an image-recording layer on the support in which the image-recording layer contains a compound represented by Formula 1C or Formula 2C and an electron-donating polymerization initiator. In Formula 1C and Formula 2C, R1C to R4C each independently represent a monovalent organic group, L1C and L2C each independently represent a divalent organic group, AC represents OH or NR5CR6C, and R5C and R6C each independently represent a monovalent organic group.
Abstract:
To provide a method of preparing a lithographic printing plate comprising exposing imagewise a lithographic printing plate precursor including a support, a photosensitive layer containing a binder polymer and a radical polymerizable compound having viscosity of 9,000 mPa·s or less at 25° C. and a protective layer in this order and developing the exposed lithographic printing plate precursor with a developer without passing through a heat treatment, as a method of preparing a lithographic printing plate capable of forming an image area which is cured at high sensitivity and has good printing durability and halftone dot reproducibility and capable of easily reproducing a halftone dot image because of excellent stability of halftone dot reproduction to exhibit a small restriction on setting of the time described above, even without conducting a preheat treatment.