发明名称 |
PROCESS FOR PREPARING CALCIUM CARBONATE |
摘要 |
<p>Inexpensive spindle- or needle-like calcium carbonate giving useful properties for bulk, brightness, opacity, wire abrasion resistance and yield as a paper filler is provided by taking advantage of the causticization step. In a first step, a quick lime having a calcium carbonate content of 10% by weight or less is slaked with a liquor having a pH of 5.5 to 13.5 at a concentration of 20 to 60% to prepare a milk of lime. In a second step, causticization reaction takes place at a green liquor loading rate of 0.02 to 0.5 cc (green liquor) /min /g (quick lime) at a reaction temperature of 20 to 105.degree.C to afford spindle- or needle-like calcium carbonate.</p> |
申请公布号 |
CA2274784(C) |
申请公布日期 |
2005.06.21 |
申请号 |
CA19972274784 |
申请日期 |
1997.12.09 |
申请人 |
NIPPON PAPER INDUSTRIES CO., LTD. |
发明人 |
TAKAHASHI, KAZUTO;NANRI, YASUNORI;OKAMOTO, YASUHIRO;KANAI, KIYOSHI |
分类号 |
C01F11/18;D21C11/00;D21H17/67;D21H19/38;(IPC1-7):C01F11/18 |
主分类号 |
C01F11/18 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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