| 摘要 |
PROBLEM TO BE SOLVED: To provide a newsprint producible by high-speed paper making, corresponding to high-speed rotary offset printing, light in weight, generating no paper powder, and excellent in opacity especially print opacity. SOLUTION: The newsprint is composed of a base paper containing hydrous silicic acid as a filler and has 36-50 g/m<SP>2</SP>basis weight in accordance with JIS P 8124, wherein the hydrous silicic acid is obtained without being subjected to a drying step after reaction, and the area ratio of the aggregate particle having≥20μm particle diameter corresponding to the detection area in a predetermined region is 10% or less, based on the size in the detection area of silicon analyzed to be hydrous silicic acid aggregate particle, in the surface analysis of the paper surface, using X-ray microanalyzer on the conditions of 8 kV X-ray acceleration voltage and 1μm diffusion area. COPYRIGHT: (C)2009,JPO&INPIT
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