Automotive synthetic leather is divided into two types:

PU synthetic leather: It features high strength, high density, and high weight, with overall performance superior to non-woven and textile fabrics. The leather made from it feels soft, full, has high tensile strength, good breathability, and excellent simulation effects.

PVC synthetic leather: It has a smooth surface and good strength, and the leather made from it is well-formed with strong simulation.

Generally, synthetic leather is divided into two layers. The layer that looks like it is woven from fabric is the base material. Of course, there are some with better quality and some with lesser quality.

In China, people are accustomed to calling synthetic leather made from PVC resin as PVC synthetic leather (abbreviated as synthetic leather);

Synthetic leather made from PU resin is called PU synthetic leather (abbreviated as PU leather):

Synthetic leather made from PU resin and non-woven fabric is called PU composite leather (abbreviated as composite leather).

The development of the synthetic leather and composite leather industry in China has become an emerging industry with considerable development potential, prominently characterized by the following features:

(1) The rapid development of synthetic leather and composite leather, with an expanding market. Nowadays, various leather products with different colors and patterns can be seen everywhere in daily life, such as indoor decoration, sofa fabrics, automotive interiors, clothing, footwear, and bags. People often think these products are made from natural leather, but in fact, a significant share of these leather products is occupied by synthetic leather and composite leather. In China, people are accustomed to calling synthetic leather made from PVC resin as PVC synthetic leather (abbreviated as synthetic leather); synthetic leather made from PU resin is called PU synthetic leather (abbreviated as PU leather); synthetic leather made from PU resin and non-woven fabric is called PU composite leather (abbreviated as composite leather). For PU synthetic leather and PU composite leather, there is currently no accurate naming in the industry, but some people habitually refer to the above three types of leather collectively as composite leather. How to name them? It remains to be unified and standardized by everyone to give it a more appropriate name. Synthetic leather and composite leather are an important part of the plastics industry and are widely used in various sectors of the national economy. The production of synthetic leather and composite leather has a development history of over 60 years internationally. China began researching and producing synthetic leather in 1958, making it one of the earlier developing industries in China's plastics industry. In recent years, the development of the synthetic leather and composite leather industry in China has not only seen an increase in production lines equipped by manufacturing enterprises, but also a continuous increase in product output and variety every year. Moreover, the industry has developed its own industry organization, which has considerable cohesion, thus bringing together Chinese synthetic leather and composite leather enterprises, including related industry organizations, to develop into a relatively strong industry. Following PVC synthetic leather, PU composite leather has achieved breakthrough technological advancements as an ideal substitute for natural leather after more than 30 years of dedicated research and development by scientific experts. PU coated on the surface of fabrics first appeared in the market in the 1950s, and by 1964, DuPont in the United States developed a type of PU composite leather used for shoe uppers. After a Japanese company established a production line with an annual output of 600,000 square meters, PU composite leather has seen rapid growth in product quality, variety, and output over more than 20 years of continuous research and development. Its performance is increasingly approaching that of natural leather, with certain properties even surpassing natural leather, reaching a level where it is difficult to distinguish between natural and synthetic leather, occupying a very important position in daily human life. Today, Japan is the largest producer of synthetic leather, with products from companies like Kuraray, Teijin, Toray, and others basically representing the development level of the international market in the 1990s. Their fiber and non-woven fabric manufacturing is developing towards ultra-fine, high-density, and high non-woven effects; their PU manufacturing is advancing towards PU dispersion liquid and PU aqueous emulsion, with product application fields continuously expanding from the initial shoe and bag sectors to clothing, sports equipment, decoration, and other special application fields, covering all aspects of daily life.

(2) The challenge of synthetic leather and composite leather to natural leather. Natural leather is widely used in the production of daily necessities and industrial products due to its excellent natural characteristics. However, with the growth of the world population, the demand for leather has increased exponentially, and the limited supply of natural leather can no longer meet this demand. To resolve this contradiction, scientists began researching and developing synthetic leather and composite leather decades ago to compensate for the shortcomings of natural leather. The more than 50 years of research history is essentially the process of synthetic leather and composite leather challenging natural leather. Scientists started by analyzing the chemical composition and organizational structure of natural leather, beginning with nitrocellulose lacquer cloth, leading to PVC synthetic leather, which is the first generation of artificial leather. Based on this, scientists made various improvements and explorations, starting with improvements in the substrate, followed by modifications and improvements to the coating resin. By the 1970s, the emergence of non-woven synthetic fibers with processes like needle punching and bonding allowed the substrate to achieve a porous structure that meets the mesh structure requirements of natural leather. At that time, the surface layer of synthetic leather could achieve a micro-porous structure polyurethane layer, equivalent to the grain surface of natural leather, thus gradually bringing the appearance and internal structure of PU composite leather closer to that of natural leather, with other physical properties approaching the indicators of natural leather, while its color is more vibrant than that of natural leather. Its normal temperature folding resistance reaches over 1 million times, and low-temperature folding resistance can also reach the level of natural leather. The emergence of ultra-fine fiber PU composite leather is the third generation of artificial leather. Its three-dimensional network non-woven fabric creates conditions for synthetic leather to surpass natural leather in terms of substrate. This product combines newly developed PU slurry with an open pore structure for impregnation and composite surface layer processing technology, leveraging the huge surface area and strong water absorption of ultra-fine fibers, giving ultra-fine PU composite leather the moisture absorption characteristics inherent to natural leather made from bundled ultra-fine collagen fibers. Therefore, in terms of internal microstructure, appearance texture, physical properties, and comfort in wear, it can compete with high-grade natural leather. In addition, ultra-fine fiber synthetic leather surpasses natural leather in terms of chemical resistance, uniform quality, adaptability to large-scale production processing, as well as waterproof and anti-mold properties. Practice has proven that the excellent performance of synthetic leather cannot be replaced by natural leather. Analyzing from both domestic and international markets, synthetic leather has already largely replaced the resource-scarce natural leather. The use of synthetic leather and composite leather for bags, clothing, shoes, vehicle interiors, and furniture decoration has increasingly gained market recognition, and its wide application range, large quantity, and variety are beyond what traditional natural leather can satisfy.