| 摘要 |
<p>A blend of an acid tolerant precipitated calcium carbonate and a platy kaolin clay is used as a filler in uncoated calendered groundwood grades of paper, such as that used in newspaper inserts, magazines, and catalogues, in order to improve the optical and physical properties, such as opacity, brightness, and porosity, of the final paper product. The amount of the acid tolerant precipitated calcium carbonate and the platy kaolin clay range from 5 % to 95 %, by weight, per amount of filler used in the paper stock furnish, and more particularly from 25 % to 75 %, by weight, per amount of filler used in the paper stock furnish. The filler loading levels range from 1 % to 40 %, by weight, based upon the total weight of the paper stock furnish. The paper product may have a brightness ranging from 70 % to 80 %, and an opacity of 85 % to 95 %.</p> |
