摘要 |
A form of calcium carbonate having a blocky-six-sided rhombohedral final crystal morphology, with a surface area of from about 3 to about 15 m<2>/g, an average discrete particle size of from about 0.2 to about 0.9 microns, wherein the discrete particles have an aspect ratio less than 2, and a particle size distribution such that at least about 60 weight percent of the particle lies within 50 percent of the equivalent discrete particle sherical diameter, suitable for use as a filler material in papermaking to improve the optical properties of the resulting paper, is disclosed. An accelerated heat-aging process, including embodiment thereof which utilize hydrothermal techniques, for rapidly producing this form of calcium carbonate and a related form of calcium carbonate having a prismatic final crystal morphology in large quantities to meet the demand of the papermaking industry, as well as a method for using these materials in papermaking are also disclosed.
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