| 摘要 |
PROBLEM TO BE SOLVED: To produce a uniform calcium carbonate excellent in dispersibility and having 0.1-1.0μm particle size. SOLUTION: At the time of forming the calcium carbonate by reacting a calcium hydroxide slurry with carbon dioxide, an org. compd. having a hydroxyl group such as glycols and ethanolamines is added preferably before the start of carbonating reaction or until carbonating ratio becomes 20% after the start of the carbonating reaction at latest. 0.1-10 pts.wt. org. compd. is added preferably to 100 pts.wt. compd. to be carbonated expressed in terms of calcium oxide. The org. compd. is mixed to the calcium oxide or calcium hydroxide powder being a starting material for example, and the mixture is dissolved into water to prepare a slaked water or a slurry, or dropped to the calcium hydroxide slurry before or after starting carbonating reaction.
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