| 摘要 |
PURPOSE:To obtain a paint for forming a lithographic printing base layer which is simply coated once on a base material and does not require surface polishing, etc. by dispersing water-insoluble inorg. powder into an aq. soln. consisting of PVA, zirconium nitrate, water soluble melamine resin and curing catalyst. CONSTITUTION:A soln. prepd. by adding guanidine sulfamate as the curing catalyst to an aq. water soluble melamine resin soln. is mixed with an aq. soln. of 5% PVA and 0.05-0.5 zirconium nitrate. The pulverous water-insoluble powder such as colloidal silica is dispersed into such soln. mixture by which the paint for forming the lithographic printing base layer is obtd. The paint is coated onto the degreased surface of a thin sheet of Al, etc. directly or after wet or dry polishing and is dried by hot wind. A photosensitive resin liquid is thereafter coated on the surface and is developed after exposure. The compsn. which has the high adhesive strength to a metallic base body and image layer, provides a smooth surface and is required to be coated once without the need for surface polishing, etc. is thus obtd. |
