When identifying, we should first check the material and determine the type of upper leather. For example, the grain surface layer of "genuine leather" has the original natural characteristics of cowhide: the pores are small, irregular and uniform; The pores and eyes of goatskin are "tile-shaped" in rows; Pigskin has a pile of three holes and is distributed in a figure of eight. Cowhide has fine tissue fibers, rough buffalo hide and rough pores and eyes. If the modified particle surface layer loses its original characteristics, it should be carefully classified and identified according to the processing technology. Aniline leather coated with aniline is characterized by crystal clear light on the surface, bright, not dazzling and strong plasticity. Natural leather is boiled into leather. Cowhide is generally 5 ~ 6 mm thick, with granular surface, fine and dense tissue fibers, smooth and beautiful, and good strength and wear resistance. The inner layer is a pile surface layer with thick fibers, large gaps and fluff on the surface. The surface of the first layer is smoother and smoother than that of the second layer, and the second layer is slightly rough. After coating, film transfer or film pasting, the surface of the two-layer leather may not be rough, but the film transfer leather has poor low temperature resistance and is easy to wrinkle at low temperature. The second layer of cowhide leather is smooth and has no obvious defects after embossing, while the second layer of pigskin leather often has three piles of pores faintly visible, where the luster is dark. It should be noted that the modified leather destroyed the original grain surface layer and then pressed the pattern. The pattern type can imitate cattle, sheep, pigskin and so on. However, the pattern has no pore eyes, and the pattern floats on the leather surface, while the pore eyes of the front leather exist, which can be identified by careful observation. Artificial leather is coated with a layer of organic material on the basis of cloth, which can be divided into thin (imitation sheepskin) and thick (coated with foamed organic material and then pressed with patterns). Synthetic leather is made by pressing organic fibers and coating and laminating. Regenerated leather is made by grinding leather residue and leather fiber, bonding them with adhesive under high pressure to form thin slices, slicing them to the required thickness, and then finishing them to make them have certain leather characteristics. They are widely used in luggage and leather parts, and a small amount are used in shoemaking. When distinguishing genuine leather from artificial materials, look at the appearance first. Genuine leather has no base, while artificial materials have a base. If you touch it again, the artificial material has a strong plastic feeling and a bright luster, but it feels cold in winter, and the leather is smooth, so it doesn't feel cold. When the soft part of the product is pressed with the thumb, many fine and uniform patterns will appear in the dermis around the thumb, and when the thumb is lifted, the patterns will disappear. However, artificial materials do not necessarily have patterns, but may also have rough patterns. When the thumb is raised, the pattern does not disappear, indicating that the grain surface layer on the surface of the material has separated from the grid layer below. We can also distinguish genuine leather from artificial leather by observing the cross section. The cross section of dermis is composed of irregular fibers. After scraping off the damaged skin fibers with nails, the cross section has no obvious change. For real leather, the texture of different parts is irregular, the nose smells fishy, while artificial leather smells plastic or rubber, and the texture rules of different parts are the same. Glued leather is a synthetic leather based on the inner layer of natural leather, which is not called "real leather", but an artificial surface layer attached to the loose fiber layer below natural leather. Dude, I've been typing word for word for over an hour. Look at that. . . . . .