1、 Raw skin treatment material

　　Raw material skin treatment includes fresh skin antisepsis, dry skin preservation, and chemical materials used in the processes of soaking, degreasing, liming, pickling and depilation. Most of the chemical materials used in the raw material skin treatment process are common chemicals such as acid, alkali, salt surfactant and so on. In addition to general chemical materials, there are also special chemical materials or ordinary chemicals used in a single process, mainly including leather degreasing agent, Liming Agent, anti-corrosion, insecticide, etc.

　　2、 Tanning Materials

　　Any chemical agent that can increase the shrinkage temperature of raw leather and form leather is called tanning agent. Tanning agent is an active substance with multi-functional groups. Tanning agents can form intermolecular bonds with two or more action points in the collagen structure. Sometimes they can increase the reaction points on some molecular chains of collagen and produce more new intermolecular crosslinks, which has tanning effect. Tanning agents can be divided into inorganic tanning agents and organic tanning agents according to their chemical properties, and can be divided into main tanning agents, pretanning agents and retanning agents according to their uses.

　　3、 Dye

　　Dyeing is an important process in leather production. Dyeing can give leather various bright and firm colors and improve the service performance of leather. The dyes used in leather can be divided into special dyes for leather and general dyes. Special dyes for leather include dip dyes and spray dyes. General purpose dyes are direct dyes and acid dyes commonly used in textile dyeing.

　　4、 Lubricating and greasing materials

　　Leather Fatliquoring (oiling) is an important process in leather production. The chemical materials used for leather fatliquoring are lubricating fatliquoring materials, which are usually called fatliquoring agents. According to the different raw materials used, fatliquoring agents can be divided into three categories: natural oils (animal and vegetable oils) and their processed products; Mineral oil and its processed products; Synthetic grease. Fatliquoring agent and fatliquoring agent can be divided into general fatliquoring agent and fatliquoring agent in leather production.

　　5、 Finishing materials

　　Leather is the processed product of various animal skins. In order to cover up the original defects of raw leather and enhance its durability, leather finishing materials have been developed. The basic components of the finishing agent are film-forming agent (or adhesive), colorant, thickener, leveling agent, plasticizer, softener, crosslinking agent and other auxiliary materials.