There are usually two methods to improve the oil resistance of paper through papermaking technology: one is to increase the beating degree of pulp; The second is to use oil repellent for treatment.
Oil proof agents can be divided into two categories: fluorinated oil proof agents and non fluorinated oil proof agents. Perfluoroalkyl compounds used in papermaking can be mainly divided into three categories: perfluoroalkyl chromium complexes, perfluoroalkyl phosphate esters, and perfluoroalkyl copolymers. Among them, the toxicity and safety of perfluoroalkyl chromium complexes are not recognized by the US Food and Drug Administration (FDA). Non fluorinated oil repellents are mainly acrylic copolymers, which have not yet been widely used.
