| 摘要 |
PURPOSE:To raise the printing resistance of original stencils for lithographic print by eliminating troubles with pollution caused by the generation of formaldehyde during the heat treatment and also preventing the deterioration of water resistance due to moisture absorption by using a comparatively large amount of a thermosetting resin obtained from reaction of polyamide urea, formaldehyde, and/or glyoxal as a water proofing agent. CONSTITUTION:On a water-resistant supporter, a surface recording layer composed of a water proofing agent, a binder of hydrophilic resin, and a pigment as main components is provided to form an original stencil for a direct-drawing type lithographic print. In this case, 55wt% or more a thermosetting resin as a water proofing agent, obtained from a procedure in which polyamidepolyamine is reacted with urea for deammoniating reaction and then reacted with epihalohydrin and/or 1,3-dihalo-2-propanol in the aqueous solution, and the reaction system is further reacted with formaldehyde and/or glyoxal, is used to the binder, and 45wt% or less hydrophilic resin is also used. The thermosetting resin to be used as a water proofing agent does not generate formaldehyde practically when heated and has no moisture absorbability. |
