| 摘要 |
PURPOSE:To obtain a blanket made of gelatin, which has improved moldability, water proofness, and hardness variability with time and is suitable for the printing of golf ball, etc., by providing an unbridged gelatin layer as an inner layer, a highly bridged gelatin layer as an intermediate layer, and a lowly bridged gelatin layer as an outer layer. CONSTITUTION:For example, a gelatin layer 4 is molded by a mold 6, and a core 5 is removed, a cross-linking agent (formaldehyde, etc.) aqueous solution is put into the layer 4 and bridged, washed with water, and dried. Then, an unbridged gelatin is put into the layer 4 in such a way that an unbridged gelatin layer is formed as an inner layer, a highly bridged gelatin layer (preferably one such as obtained by bridging treatment with 1% formalin for 4hr, having a bridging degree at which compressive stress becomes 160-200% of an unbridged product of the same composition) as an intermediate layer, and a lowly bridged gelatin layer (preferably one such as obtained by gridging treatment with 0.5% formalin for 30mu, having a bridging degree at which the compressive stress becomes 110-150% of an unbridged product of the same composition) as an outer layer. Thus, a rubber drum blanket for offset printing can be obtained. |
