What is the role of light calcium carbonate in the paper industry?

2020-04-08 2908 time BACK

The latest development in the application of light calcium carbonate in PCC of papermaking industry refers to a product prepared by chemical synthesis, which is formed by introducing carbon dioxide into lime water or directly precipitating under the action of sodium carbonate solution and lime water. The quality of light calcium carbonate is superior to heavy calcium carbonate. Its particle size is small, porous and narrow. It has the advantages of fine particle size, high whiteness, low price, low foaming and good printing adaptability. Very suitable for paper packing, basically meet the requirements of paper printing and optical properties. Therefore, light calcium carbonate is used as a filler for some high-grade paper. By comparing the effects of adding light calcium carbonate and kaolin on the quality performance of the base paper, Li Dan found that the super glazed paper with light calcium carbonate had higher whiteness and opacity, while the printing parameters such as smoothness, paper gloss, printing gloss and fluidity were similar to those of kaolin. A possible issue is the potential impact of the high voidage of light calcium carbonate on printing concentration, ink requirements, and printing uniformity. Jia Tian Xiang research found that light calcium carbonate can improve and improve coated board whiteness, smoothness, surface strength and ink absorption.

The whiteness, opacity, looseness, evenness and smoothness of the electrostatic carbon paper filled with light calcium carbonate have been greatly improved, the printing suitability of the paper has been improved, the ash content of the paper has been increased, and the shape stability of the paper has been improved. Yong-shun liu and other researchers found that adding light calcium carbonate light weight printing paper has high volume of paper and opacity, good printing performance, good paper evenness and fineness, to reduce the glare of paper, increase paper ash, smoothness and shape stability, but unfavorable to the sizing, the tensile strength and surface strength of paper. Zhang Yang's research found that light calcium carbonate can partially replace calcined kaolin for carbon-free carbon paper, which is beneficial to save the cost of papermaking. There is no binding force between light calcium carbonate and pulp fibers, resulting in low retention rates. Therefore, light calcium carbonate usually needs modification before use. The modification of light calcium carbonate can be divided into two processes: dry process and wet process. Wet - modified product quality is good, the amount of surfactant is low. However, when using modifiers that are easily hydrolyzed or insoluble in water, a dry modification process is required. Dry surface modification is a widely used method, which is simple and easy to be used in industrial production.