In paper making process, adding fillers is very common in paper mills, the original purpose is to lower furnish costs with the amount of filler limited only by strength considerations, nowadays in order to improve the paper quality, fillers will be added to increase the paper brightness, smoothness, opacity, stiffness and so on.
1. Fillers can give the paper a specific property, increase the paper brightness, smoothness, opacity, stiffness and so on;
2. The addition of filler causes the paper internal voids to become smaller and smaller, thereby increase the paper ink absorbency and make it evenly;
3. Improve sheet formation by filling in the void areas around fiber crossings;
4. Provide cost savings by replacing higher cost fiber with lower cost fillers;
The most commonly used inorganic fillers are talcum powder, clay, titanium dioxide and calcium carbonate. Which titanium dioxide is expensive high-quality filler; organic synthetic filler for some high molecular substances.
