Classification of leather

Classification of leather Leather is generally divided into textures: 1. Natural leather. 2. Synthetic leather. 3. Textile materials 1. Artificial leather is divided into artificial foam leather and synthetic leather.

1. The artificial foam leather is mainly made of polyurethane, woolen cloth, polyamino resin and other resins, and is made of cloth as the base material. It is characterized by being airtight and mainly used for making handbags, belts, etc.

2, the surface of the synthetic leather is mainly polyurethane, the base material is a non-woven fabric made of synthetic fibers such as polyester, cotton, polypropylene, etc. It has a certain permeability, and the characteristics are beautiful luster, not easy to mold and insects.

(1) Synthetic leather.

The surface is smooth, the thickness of the sheet is thick, the color, the strength and the like are uniform, and it is superior to the natural skin in water resistance, acid and alkali resistance and microorganisms. But it is not resistant to high temperatures, cold, and aging.

(2) Artificial leather.

It is made of plain cloth, canvas, rat fabric, recycled fabric, fiber knitted fabric, etc., and then processed with different finishing materials.

Commonly used are: PVC artificial leather, PVC foam leather, etc.

(3) Textile materials.

There are fine canvas, cotton blended fabric, vinylon cloth, plain cloth, cashmere, and so on.

2, animal leather is a kind of natural leather, that is, we often say that the animal (raw skin) through a series of physical and chemical processing into a fixed, durable material, it is soft, tough, difficult to meet water Deformation, drying is not easy to shrink, heat and humidity resistance, chemical resistance, etc. It has special advantages such as good gas permeability and anti-aging.

The processing of animal leather is very complicated, and it takes several dozen processes to make finished leather: raw hide————————————– -Expansion—-Deashing—-Softening—-Immersion Acid—-Tanning—-Layering—-Shaving—-Recovering—-Neutralization– –Dyeing and refueling——-drying—-finishing—-finishing—-finished leather.

There are also many types of animal leather. According to the materials, there are sheep leather, cow leather, horse leather, snake leather, pig leather crocodile leather, etc.

According to the performance, it can be divided into two layers of leather, full grain leather, suede leather. , modified leather, film leather, composite leather, coated split leather.

Two-layer leather refers to the compression of pulverized leather by chemical and physical methods in leather processing. This type of leather is hard, easy to break, and has insufficient elongation.

Full grain leather: refers to the leather that retains and uses the surface of the animal’s skin (growth or scale side), called the front leather. The full-grain surface is used less directly without being painted. Most of them are embossed, such as embossing. The raw materials used in full-grain leather require high-grade raw materials with disability, and the processing requirements are also high. Leather, and the surface of the leather is completely retained in the skin, and its firmness is good. The surface of the full grain leather is unfinished or finished and thin, maintaining the soft elasticity and good breathability of the leather. Comfortable, durable and beautiful.

Suede: refers to the surface of the leather, which is made of velvet leather. The front side of the leather (grown on the side of the hair or scale) is called the nubuck, and the reverse side of the leather (the flesh side) is called the anti-velvet. The second layer of velvet leather is called the second layer velvet. Since the suede leather has no finishing layer, its air permeability is better, the softness is improved, but its water repellency, dustproof and maintenance property are deteriorated, and there is no grain surface. The softness of the nubuck leather is lowered. Suede products are comfortable to wear and have good hygienic performance. However, besides suede made from oily method, suede

leather is easy to be dirty and difficult to clean and maintain. It is mainly used in leather shoes, leather garments, leather bags and gloves.

Modified leather: refers to leather that partially or completely removes the original surface of animal skin, and then applies artificial film on it. It has top-grade modified leather and two-layer modified leather. The surface film is mostly made of various chemical materials. The finishing liquid is made by repeatedly coating and pressing some patterns, and some finishing leather is to transfer the pre-made chemical film to the leather surface, also called transfer film or film leather. The finishing leather is mainly to make up the surface of the material. Insufficient, its poor gas permeability, low fastness, reduced folding resistance and aging resistance, wearing less comfortable than full grain leather, but its water resistance is good, easy to clean and maintain.

Composite leather refers to a rubber film laminated on the split skin, which has good chemical resistance and durability.