PURPOSE: To produce a mat coated paper excellent in quality without transferring printed ink to a white paper part in a book making process after printing and without impairing balkiness by calender treatment.
CONSTITUTION: Low-pressure and lightly heated steam is applied to a base paper before the mat coating to humidify and heat the surface of the paper, a soft calendering treatment is carried out at 100-150°C and then a coating composition containing 50-95wt.% ground calcium carbonate having 0.5-1.5μm average particle diameter and 5-50wt.% kaolin is applied to the base paper. The base paper is treated at ≥100°C using a mat roll having its surface roughness (Rmax) of 2-8μm defined according to JIS-B 0651 and subjected to calender finishing so as to give ≤35% glossiness (JIS P-8142, 75° white paper glossiness) to provide the objective high-quality mat coated paper.
SATO TOMOJI
SAKAMOTO SHO
