What are the commonly used papermaking additives?
Sizing agent is also called sizing agent. Sizing refers to a process core technology that applies sizing material to pulp or paper. Its purpose is to maintain the dimensional stability of the paper, prevent shrinkage, and at the same time reduce the water absorption and ink absorption of the paper, and improve the smoothness of the paper , Printing adaptability, improve paper quality. This agent is relatively stable, generally stable for more than 90 days. Adding to paper pulp has good effects on improving water resistance, softness, printing adaptability, smoothness, etc. It has good compatibility with pulp and can obtain paper with good permeability. Used for sizing of paper or cardboard, it can significantly improve the quality of paper and cardboard.
Retention aid is used to increase the retention of fillers, fine fibers, sizing agents, etc., reduce their loss, and improve the drainage and dehydration of the paper; it can also be used as a trap for "anionic garbage". Adding outside the copper mesh of the paper machine facilitates solid-liquid separation, improves paper machine efficiency and reduces production costs, and can also be used as a flocculant for papermaking wastewater.
The forming process of wet paper sheet is a complex physical and chemical process. The fibers, fine fibers, interfering substances, fillers, pigments, rubbers, chemical additives, etc. in the papermaking ingredients all have complex surface and colloidal chemical properties. In particular, surface chemical phenomena such as charge, specific surface area, and adsorption of paper-making ingredients not only affect the improvement of paper quality, but also affect the normal operation of the paper machine. Paper mills can generally increase the strength of paper, increase the retention of fines and improve the drainage performance by adding chemical additives. This type of additive is called a wet end additive.
