Natural leather is widely used in the production of daily necessities and industrial products due to its excellent natural characteristics, but with the growth of the world's population, the demand for leather has doubled, and the limited number of natural leather has long been unable to meet people's needs. In order to solve this contradiction, scientists began to research and develop artificial leather and synthetic leather decades ago to make up for the lack of natural leather. The research history of more than 50 years is the process of challenging artificial leather and synthetic leather to natural leather.
Scientists started from the study and analysis of the chemical composition and tissue structure of natural leather, starting from nitrocellulose lacquered cloth and entering PVC artificial leather, which is the first generation of artificial leather. On this basis, scientists have made many improvements and explorations, first in the improvement of the substrate, and then in the modification and improvement of the coating resin. In the 70s of the 20th century, the non-woven fabric of synthetic fibers appeared needle-punched into a net, bonded into a net and other processes, so that the substrate has a lotus-like section and hollow fiber-like, reaching a porous structure, and meeting the requirements of the network structure of natural leather; At that time, the surface layer of synthetic leather has been able to achieve a microporous structure polyurethane layer, which is equivalent to the grain surface of natural leather, so that the appearance and internal structure of PU synthetic leather are gradually close to that of natural leather, and other physical properties are close to the indicators of natural leather, and the color is more vivid than natural leather; Its folding resistance at room temperature can reach more than 1 million times, and the low temperature folding resistance can also reach the level of natural leather.
The emergence of microfiber PU synthetic leather is the third generation of artificial leather. Its three-dimensional structural network of non-woven fabrics creates conditions for synthetic leather to catch up with natural leather in terms of substrates. The product combines the newly developed processing technology of PU slurry impregnation and composite surface layer with open cell structure, which plays a huge surface area and strong water absorption of ultra-fine fiber, so that the ultra-fine PU synthetic leather has the inherent hygroscopic characteristics of natural leather of bundled ultra-fine collagen fibers, so it can be comparable to high-grade natural leather in terms of internal microstructure, appearance texture and physical characteristics and people's wearing comfort. In addition, microfiber synthetic leather surpasses natural leather in terms of chemical resistance, quality uniformity, adaptability to large-scale production and processing, and waterproofing and mildew resistance.
Practice has proved that the excellent properties of synthetic leather are irreplaceable by natural leather, and from the analysis of domestic and foreign markets, synthetic leather has also replaced a large number of natural leathers with insufficient resources. The use of artificial leather and synthetic leather for luggage, clothing, shoes, vehicles and furniture decoration, has been increasingly affirmed by the market, its wide range of applications, large quantities, many varieties, is the traditional natural leather can not be satisfied.
