| 摘要 |
PROBLEM TO BE SOLVED: To obtain high printing durability, scratching resistance and contamination, resistance by incorporating a matting agent comprising fine particles of a small average particle size into a silver halide emulsion layer and incorporating a matting agent comprising particles of a large average particle size into a base coating layer so as to control the center line average roughness of a lithographic printing material to a specified range. SOLUTION: The matting agent comprising fine particles to be added to a silver halide emulsion layer has the average particle size smaller than the dry film thickness of the binder of the silver halide emulsion layer. Preferably, the matting agent has 0.1 to 1.0μm average particle size. The matting agent to be added to the base coating layer contains particles having a larger average particle size than the fine particles of the matting agent incorporated into the silver halide emulsion layer. The average particle size is >=1.0μm, preferably 1.5 to 5μm. The amt. of the matting agents incorporated into the silver halide emulsion layer and the base coating layer depends on the average particle size, particle content and binder content of each matting agent used for the respective layer, however, the amt. is controlled to obtain 0.6 to 1.2 center line surface roughness Ra. |
