公开(公告)号：US5230734A

公开(公告)日：1993-07-27

申请号：US917163

申请日：1992-07-20

申请人： Tetsuo Kumasaka ,  Hideki Horiuchi ,  Fumihiko Kaneko ,  Tatsuo Takano

发明人： Tetsuo Kumasaka ,  Hideki Horiuchi ,  Fumihiko Kaneko ,  Tatsuo Takano

IPC分类号： C01F11/18 ,  C09C1/00 ,  D21H19/38

CPC分类号： D21H19/385 ,  C01F11/18 ,  C01F11/181 ,  C09C1/009 ,  C01P2004/10 ,  C01P2004/20 ,  C01P2004/52 ,  C01P2004/54 ,  C01P2004/62 ,  C01P2006/12

摘要： A calcium-magnesium carbonate composite consisting of particles of calcium carbonate and magnesium carbonate hydroxide and having excellent properties, for example, as a pigment for paper coating is proposed, which is a uniform blend of:(A) particles of calcium carbonate having a crystalline structure of aragonite with a columnar particle configuration having a length in the range from 0.5 to 3 .mu.m and a diameter in the range from 0.1 to 0.3 pm with an aspect ratio in the range from 5 to 15; and(B) particles of magnesium carbonate hydroxide having a plate-like particle configuration with a particle diameter in the range from 2 to 7 .mu.m and a thickness in the range from 0.05 to 0.5 .mu.m,the blend having an overall specific surface area in the range from 15 to 30 m.sup.2 /g and the weight proportion of the particles of calcium carbonate to the particles of magnesium carbonate hydroxide being in the range from 95:5 to 50:50 calculated as the respective hydroxides. The carbonate composite can be prepared by the step-wise carbonation reaction of a mixed aqueous slurry of calcium and magnesium hydroxides with carbon dioxide gas under very strictly controlled conditions.

公开(公告)号：US5879442A

公开(公告)日：1999-03-09

申请号：US998034

申请日：1997-12-23

申请人： Hiroyuki Nishiguchi ,  Kazuhisa Shimono ,  Tetsuo Kumasaka

发明人： Hiroyuki Nishiguchi ,  Kazuhisa Shimono ,  Tetsuo Kumasaka

IPC分类号： C01F11/18 ,  C09C1/02 ,  D21H19/38 ,  D21H19/54 ,  D21H19/58

CPC分类号： C01F11/185 ,  C09C1/021 ,  D21H19/385 ,  B41M5/5218 ,  C01P2004/61 ,  C01P2004/62 ,  C01P2006/12 ,  C01P2006/22 ,  D21H19/54 ,  D21H19/58

摘要： Proposed is a method for the preparation of an aqueous slurry of calcium carbonate particles suitable as a base pigment in the preparation of a paper coating composition having excellent water retentivity and high solid concentration with good flowability, which contains precipitated and ground calcium carbonate particles in combination in a specified weight proportion and characterized by several parameters. The aqueous slurry is prepared in a process comprising the steps of: (a) subjecting an aqueous slurry or wet cake containing a specified amount of specific precipitated calcium carbonate particles to a primary dispersing treatment using a mixer to a specified extent; (b) admixing the aqueous slurry with a specified amount of specific ground calcium carbonate particles; (c) subjecting the aqueous slurry to a secondary dispersing treatment using a mixer to a specified extent; and (d) subjecting the aqueous slurry to a tertiary dispersing treatment using a sand grinder to a specified extent.

摘要翻译： 提出了一种制备适合作为基础颜料的碳酸钙颗粒的水性浆料的方法，其制备具有优异的保水性和高固体浓度以及良好流动性的纸涂料组合物，其含有沉淀和研磨的碳酸钙颗粒的组合 以指定的重量比例，并用几个参数表征。 含水浆料的制备方法包括以下步骤：（a）使含有特定量的特定沉淀碳酸钙颗粒的含水浆料或湿滤饼在一定程度上进行初步分散处理; （b）将含水浆料与指定量的特定磨碎的碳酸钙颗粒混合; （c）使用混合器对含水浆料进行二次分散处理至一定程度; 和（d）使用砂磨机对含水浆料进行三级分散处理达到规定的程度。