Patent ID: 7081330
Filing Date: 2006-07-25
Classification: G03F,Y10S

Abstract:
1. A method of making a lithographic printing plate from a heat-sensitive pre-sensitized plate of a positive-working mode for lithographic printing comprising the steps of: exposing the heat-sensitive pre-sensitized plate to light, and developing the plate using an alkaline developing solution comprising at least one compound having three or more ethylene oxide-terminal groups in the molecule thereof, wherein the pre-sensitized plate comprises a substrate, a lower layer which comprises a water-insoluble and alkali-soluble resin, and an upper heat-sensitive layer which comprises a water-insoluble and alkali-soluble resin and an infrared absorption dye and exhibits an elevated solubility with respect to alkaline aqueous solutions when heated, said lower layer and said upper heat-sensitive layer being located on the substrate in this order.