| 摘要 |
PROBLEM TO BE SOLVED: To provide a mixed calcium carbonate slurry having a high solid content concentration, excellent in optical and printing characteristics, and having a low viscosity and high speed fluidity. SOLUTION: This mixed calcium carbonate slurry is obtained by mixing the dispersed slurry of spindle-shaped or scalenohedron-shaped light calcium carbonate, whose particles have an average minor axis and an average major axis of <=0.45μm and <=1.50μm, respectively, and a prescribed median diameter (PCC50) of 0.02-2.00μm, with heavy calcium carbonate pulverized in a dry state, and then subjecting the mixture to a sand-grinding treatment to form the slurry. Therein, the properties of the slurry satisfy the following inequality: 0.75<=PCC50/Mix50<=2.00 (Mix50 is the prescribed median diameter of the calcium carbonate particles in the sand-ground slurry), and the retention percentage (R), expressed by the following equation, of the calcium carbonate particles keeping the prescribed shape exceeds 50%. R(%)=(Mix-L/ PCC-L)×100 (PCC-L is the average major axis of the spindle-shaped or scalenohedron-shaped light calcium carbonate particles in the dispersed slurry; Mix-L is the average major axis of the spindle-shaped or scalenohedron-shaped calcium carbonate particles in the sand-ground slurry).
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