Calcium carbonate for papermaking
In the raw materials for paper, in addition to pulp fibers, pigments, fillers in the forefront of the amount. Common paper fillers are calcium carbonate, talcum powder, titanium dioxide, kaolin a few, some special paper will involve silicate, sulfate, mica and magnesium hydroxide and other inorganic fillers.
Calcium carbonate for papermaking can be divided into two types according to its use: paper filler and coating pigment, and heavy calcium carbonate and light calcium carbonate according to different manufacturing methods. On the one hand, it can improve the opacity and ink absorption of paper, on the other hand, calcium carbonate is one of the important traditional fillers in paper industry.
Heavy calcium carbonate series
Light calcium carbonate series
Specification for calcium carbonate for papermaking
With the continuous development of papermaking technology, the demand for calcium carbonate is also changing, the technical indicators gradually clear and rigorous. On April 1,2020, the standard QB/T2811 -2019 for calcium carbonate for papermaking, one of the drafters of Shanghai Dongsheng New Materials Co. , Ltd. , was formally changed. Instead of QB/T2811 -2006 paper grinding calcium carbonate formal implementation.
According to the new standard, calcium carbonate for papermaking can be divided into filler-grade calcium carbonate and coating-grade calcium carbonate. The filler grade calcium carbonate includes heavy calcium carbonate (ground calcium carbonate) and light calcium carbonate (precipitated calcium carbonate) , and the coating grade calcium carbonate includes bottom-coated calcium carbonate and surface-coated calcium carbonate. In addition, calcium carbonate for paper products can be divided into: powder calcium carbonate, paste calcium carbonate and paste calcium carbonate.
