How is the leather graded?

The first layer of skin is the outermost layer of cowhide, with granular surface and natural scars. The dermis, fiber layer and villous layer of the head layer are closely connected with each other, and the strength, elasticity, flexibility, air permeability and water absorption are good.

The second layer of skin is the "lower layer" after peeling off the first layer of skin, it has no surface dermis, only fibrous layer and villous layer, and the structure is relatively loose. The second layer of skin needs to be treated by finishing and polishing before it can be used as a skin, and its flexibility and durability are worse than that of the head layer.

Automotive leather seats require high wear resistance, so it is better to use the first layer of leather. However, some models will use two layers of leather or even synthetic leather in the equal corner position on the side of the seat.

The most important factor that determines the quality of a skin is the number of its own congenital defects and defects. Cattle in the growth process, there will be a variety of factors cause scars, such as growth lines, mosquito gadfly bites, abrasions, stab wounds, vascular striations, tears and so on.

In the process of leather production, we need to use polishing, finishing and other processes to deal with these defects. The fewer natural scars, the lighter the degree of subsequent treatment, the thinner or even no need for finishing, and the higher the corresponding leather level.

The best quality skin defects are very few, the surface does not need to be polished, and the grain is completely retained, which is called whole-grain flour skin (full grain). Full-grain skin pores are clear, small, compact, plump and meticulous, with natural texture, elasticity and good air permeability.
The skin with more defects needs to be polished to remove the defects, and then manually embossed, called grinding skin, or Corrected Grain.