Nike shoes how to distinguish is the first layer of skin and second skin

The leather is divided into layers, with the first layer and two layers of skin. The top layer has grain, skin, embossed, special effect skin and embossed skin. The second layer is divided into second layer of pig and second layer of cattle.

The first layer of skin is grainy cattle, sheep, pigskin, etc. There are natural scars and blood marks on the surface of the skin. Occasionally there are knife wounds in the processing process and the intestines where the utilization rate is extremely low. Skin also has the cattle's numbering imprint. Full grain hides can be distinguished from animal skins by the size and density of the pores. There are many types of leather, such as cowskin, beef cattle, grazing cows, cowskins, bullskins, uncut bulls, and castrated bulls. In China, there are yellow leather, buffalo leather, yak skin and yak skin. Among them, buffalo hides have coarser and more sparse pores; yellow leather has finer and denser pores than buffalo hides. The pores of sheepskin are finer, denser, and slightly slanted. There are mainly two types of sheep skin and goat skin. The rule of long-haired pigskin is the distribution of 3 to 5 roots and a small beak, so it is easy to distinguish. Generally, pigskins are kept artificially. There are also wild boar skins. The famous wild boars are South American boars. Pork skin pores and grain features, due to its special collagen fiber structure, can be processed into a very soft garment leather or gloves leather, a high value. In addition, ostrich skin, crocodile skin, short-nose crocodile skin, lizard skin, snakeskin, bullfrog skin, saltwater fish skin (having shark skin, eel skin, eel skin, eel skin, pearl skin, etc.), freshwater skin ( There are scale fish skins such as grass carp and squid skin, hairy foxes (silver foxes, blue foxes, etc.), wolf skins, dog skins, rabbit skins, etc. are easily recognizable and cannot be made into two-layer skins.

The first layer of skin is directly processed from the raw skin of various animals, or the skin of cattle, pigs, horses, etc. in the thicker skin is cross-sectioned and cut into upper and lower layers. The upper part of the tightly fibrous tissue is processed into various heads. Layer skin.

(2) The second layer of skin is a relatively loose second layer of fibrous tissue that has been chemically sprayed or coated with PVC or PU film.

Therefore, an effective method for differentiating between the scalp skin and the second skin is to observe the longitudinal section fiber density of the skin. The first layer of skin is composed of a dense and thin layer of fibers and a slightly loose overlayer that is closely associated with it, and has good strength, elasticity, and process plasticity. The second layer of skin has only a loose fibrous tissue layer, and can only be used to make leather products after spraying chemical raw materials or polishing. It maintains a certain natural elasticity and process plasticity characteristics, but its strength is poor, and its thickness requires the same layer. Like skin.

Two-layer skin: Thick skin is obtained by splitting the skin machine, the first layer is used to make full-grain leather or shave, and the second layer is made into two-layer skin through series of processes such as painting or coating, and its fastness and wear resistance Poor, it is a relatively cheap one of the same type of leather. In addition to the second skin there are three skins, and the third skin is the worst cowhide leather.

With the above knowledge, I believe we all know how to distinguish between the first and second floors of the NIKE shoes.