Leather chemical materials are special chemical materials for leather and fur, which play a very important role in leather and fur, and it is divided into seven categories: raw skin treatment materials, tanning materials, dyes, lubricating grease materials, finishing materials, functional finishing materials and fur materials.

Raw skin treatment material

Raw skin treatment includes fresh skin preservative, dry skin preservation, as well as soaking, degreasing, ash, acid, hair removal and other chemical materials used in the process.

Most of the chemical materials used in the treatment of raw materials are common chemicals such as acids, alkalis and salt surfactants. In addition to general chemical materials, there are special chemical materials or common chemicals used for a single process, mainly including leather degreaser, lime leaching agent, anti-corrosion, insecticides and so on.

Tanning material

Any chemical preparation that can increase the shrinkage temperature of raw skin and can form leather is called tanning agent.

Tanning agent is a kind of active substance with multiple functional groups. Tanning agents can form intermolecular bonds with two or more application points in collagen structure, and sometimes increase reaction points on a part of the molecular chain in collagen and produce more new intermolecular crosslinks, which has tanning effect.

Tanning preparations can be divided into inorganic tanning agents and organic tanning agents according to their chemical properties, and can be divided into main tanning agents, pre-tanning agents and retanning agents according to their uses.

Dye

Dyeing is an important process of leather production, through dyeing can give leather a variety of bright and firm colors, improve the performance of leather. The dyes used for leather can be divided into leather special dyes and universal dyes, and the special dyes for leather have dye for immersion and dye for spray dyeing. Universal dyes are direct dyes and acid dyes commonly used in textile dyeing.

Lubricate the grease material

Leather fat (refueling) is an important process in the leather production process, the chemical material used for leather fat is lubricating fat material, usually called fat agent. According to the different raw materials used, the fat agent can be divided into three categories: natural oil (animal and plant oil) and its processed products; Mineral oil and its processed products; Synthetic oils and fats. According to the function in leather production, it can be divided into general type fat and multi-function fat, such as white leather fat, waterproof retanning fat and so on.

Finishing material

Leather is the processed product of various animal skins. In order to conceal the original defects of the raw skin and enhance the durability, leather finishing materials have been developed. The basic components of the finishing agent are film forming agent (or adhesive) and coloring agent, as well as auxiliary materials such as thickening agent, leveling agent, plasticizer, softener, crosslinking agent, etc.

Functional finishing materials

Functional finishing materials are designed to make up for the defects or improve or add some characteristics after tanning and finishing of leather. For example, the leather filler is mainly for the problems of poor leather parts and loose surface after tanning, and can make the leather full and elastic after filling, and improve the phenomenon of poor parts and loose surface. The feel agent is mainly to improve the feel effect of the coated leather surface. There are many types of finishing materials, which have been included in the additives in the past, according to the development of recent years, fillers, feel agents, preservatives and other functional finishing materials have become an independent system and become indispensable materials for the production of high-grade leather.

Fur material

Fur production process includes preparation process, tanning process and finishing process. In each process, some chemical materials need to be used, most of the chemical materials used in fur production are the same as the materials used in leather, but the fur needs to be treated to improve the luster of the hair, dyeing, and improve the use value.

The main fur materials are:

(1) Raw plate treatment material

The treatment materials of wool board mainly include water dipping agent, preservative, degreaser, acid dipping agent, enzyme preparation, tanning agent, fatting agent and so on. Most of the materials are common with leather materials, and some of them are more suitable for fur treatment, and the effect is obvious.

(2) wool finishing materials

The use value of fur lies in the quality of the coat, and the dyeing and finishing of the coat occupy an important position. At present, oxidized dyes are mainly used for fur dyeing, and the finishing materials are mainly gloss agents, with fewer varieties to be developed.

(3) fur finishing agent

Fur finishing agent is mainly used to treat the coat with luster, make the wool bright and smooth, and improve the use value.