I. What is Artificial Leather
Artificial leather, also known as synthetic leather or faux leather, is a material designed to mimic the look and feel of genuine leather.It’s created using various synthetic materials like polyurethane (PU), polyvinyl chloride (PVC), or even plant-based alternatives.
A polymer material product similar to leather. Usually, a layer of resin mixture is applied or pasted on the fabric as the base, and then heated to plasticize it, and rolled flat or embossed to obtain the product. It is similar to natural leather and has the characteristics of softness and wear resistance.
In China, people are accustomed to calling artificial leather produced with PVC resin as raw material PVC artificial leather (abbreviated as artificial leather); artificial leather produced with PU resin as raw material is called PU artificial leather (abbreviated as PU leather); artificial leather produced with PU resin and non-woven fabric as raw materials is called PU synthetic leather (abbreviated as synthetic leather), Synthetic leather.
Artificial leather is the earliest invented substitute for leather fabrics. It is made of PVC plus plasticizers and other additives calendered and compounded on cloth. The advantages are low price, rich colors and various patterns, and the disadvantages are easy to harden and become brittle.
PU synthetic leather is used to replace PVC artificial leather, and its price is higher than PVC artificial leather. In terms of chemical structure, it is closer to leather fabrics. It does not use plasticizers to achieve soft properties, so it will not become hard or brittle. At the same time, it has the advantages of rich colors and various patterns. The price is cheaper than leather fabrics, so it is popular with consumers.
II. Distribution of Chinese Artificial Leather Factorys
Chinese artificial leather and synthetic leather production enterprises are mainly distributed in the Pearl River Delta, the Yangtze River Delta, Beijing, Tianjin, Hebei, Hunan, Shandong Peninsula and other coastal developed provinces and cities.
There are nearly 1,000 artificial leather and synthetic leather enterprises above designated size in China, and more than 400 of them are analyzed: the total number of enterprises in East China and Central and South China accounts for more than 60%, more than 200 in Jiangsu Province and Zhejiang Province, and more than 30 in Hebei Province.
There are more than 100 “Wenzhou Synthetic Leather Capital” areas developed in the Wenzhou model, and 22 artificial leather production bases in Zhouzhuang Town in the form of Jiangnan model.
III. Types of Artificial Leather
Due to the different synthetic resins used in artificial leather, different types of substrates, different production processes, whether there is foaming and different uses, artificial leather can be divided into many categories. Artificial leather is now classified according to the synthetic resin used, production process and purpose.
3.1 Classification by Synthetic Resin Used
1. Polyvinyl chloride artificial leather PVC (first generation artificial leather)
It is a mixture of polyvinyl chloride resin, plasticizer and other compounding agents, coated or laminated on fabric, and made into a wake-up product through a certain processing process. In addition, there is also double-sided polyvinyl chloride artificial leather with plastic layers on both sides of the substrate.
(1) Ordinary artificial leather. Also known as non-foamed artificial leather. It is mostly made of plain cloth, canvas, and recycled cloth as the base and is made by direct coating. Because the coating is dense and the paste can penetrate into the pores of the base cloth, the finished product feels hard and wear-resistant. It is mainly used to make wear-resistant packaging bags, construction and industrial accessories, etc.
(2) Foamed artificial leather. Usually, it is mostly made of knitted cloth as the base. The surface paste contains foaming agent and its additives. When it is gelled, it foams to form a microporous structure, so the finished product is light, plump and soft. It is produced by transfer coating. It is mostly used to make gloves, bags, clothing and furniture.
(3) Suede artificial leather（Microfiber leather）. Commonly known as artificial suede. There are many varieties and production methods. The microporous surface layer of the artificial leather after gelation can be made into suede leather after grinding with a sand roller. The coating layer is raised and stretched with a raising roller to produce curly suede leather. It is suitable for use as the toe cap and edging material of sports shoes. Adding soluble salts (such as table salt) to the coating paste, dissolving the salt with water after gelation, can make the surface layer microporous and suede-like. Using the electrostatic flocking method, 0.5-1mm long synthetic fiber short pile is planted on the polyvinyl chloride artificial leather coated with adhesive to produce flocked leather, which is suitable for making packaging bags and decorations.
2. Polyurethane artificial leather PU (second generation artificial leather)
Polyurethane artificial leather is divided into dry polyurethane artificial leather and wet polyurethane artificial leather.
Dry-process polyurethane artificial leather refers to a multi-layer structure formed by adding a base fabric to a multi-layer film obtained by evaporating the solvent from a solvent-based polyurethane resin solution.
Wet-process polyurethane artificial leather is a multi-layer structure with good air permeability and moisture permeability and a continuous porous layer obtained by using a solvent-based polyurethane resin in an underwater film-forming method.
3. Superfine fiber synthetic leather (third-generation artificial leather)
Superfine fiber PU synthetic leather is the third generation of artificial leather. Its three-dimensional structural network of non-woven fabrics has created conditions for synthetic leather to surpass natural leather in terms of substrate. This product combines the newly developed PU slurry impregnation with an open-pore structure and the processing technology of the composite surface layer, giving full play to the huge surface area and strong water absorption of superfine fibers, so that the superfine PU synthetic leather has the inherent moisture absorption characteristics of natural leather with bundled superfine collagen fibers. Therefore, whether in terms of internal microstructure, appearance texture, physical properties, and people’s wearing comfort, it can be comparable to high-grade natural leather. In addition, microfiber synthetic leather exceeds natural leather in chemical resistance, quality uniformity, adaptability to large-scale production and processing, as well as waterproof and mildew resistance.
Secondary cowhide is made by crushing the scraps of the first layer of cowhide and adding nylon microfiber and polyurethane in proportion to form a resin to make leather pulp, and then using mechanical calendering to make a piece of “leather embryo”, and then coating or wet or dry laminating with PU film for secondary processing.
4. Polyamide artificial leather PA
Polyamide artificial leather is a plastic product with a continuous pore structure made by slowly covering the fabric with nylon 6 or nylon 66 solution.
It has better moisture permeability and moisture absorption than polyvinyl chloride artificial leather, and has a better appearance and feel. It is often used to make boxes, bags, etc.
5. Polyolefin artificial leather PE
Polyethylene artificial leather is a foamed artificial leather. It is made of low-density polyethylene resin as the main raw material, mixed with modified resin, cross-linking agent, lubricant, foaming agent and other components.
This artificial leather is light, firm, and has a smooth surface. It is used to make leather bags and handbags.
3.2 Classification by Substrate
According to the substrate material, it is divided into cotton cloth-based, synthetic fiber-based and fiber-based. Among them, cotton cloth-based includes plain cloth, bleached cloth, dyed plain cloth-based artificial leather, canvas-based artificial leather, knitted cloth-based artificial leather and raised cloth-based artificial leather; synthetic fiber-based includes nylon-spun polyurethane artificial leather and wet single-coated polyurethane artificial leather; fiber-based includes paper-based polyvinyl chloride artificial leather and non-woven fabric-based artificial leather.
The substrates used in large quantities in my country are various types of cotton cloth, such as plain cloth, bleached cloth, dyed plain cloth, canvas, knitted cloth (including synthetic fiber), raised cloth, recycled cloth, non-woven fabric, etc.; some use cotton/chemical fiber blended cloth, such as nylon knitted cloth, etc.; a small amount of chemical fiber cloth is used, such as nylon silk, polyester silk, etc.; and synthetic fiber non-woven fabrics are rare. With my country’s reform and opening up, technological progress and the rapid development of the petrochemical industry, chemical fiber cloth and synthetic fiber non-woven fabrics will develop rapidly.
3.3 Classification by Production Method
1. Direct scraping artificial leather
The rubber material is directly scraped on the pre-treated base fabric with a scraper, and then put into the plasticizing box for gelation and plasticization, and then embossed, cooled and other processes to obtain the finished product.
2. Transfer scraping artificial leather
The transfer scraping method is also called indirect scraping method. The carrier used is release paper or stainless steel belt, so it is divided into release paper method and steel belt method. It is to scrape the paste on the carrier with a reverse roller or a scraper. After gelation, the base fabric is compounded on the gelled material layer without tension, and then plasticized, cooled, and peeled off from the carrier, and then processed to obtain the finished product.
3. Calendering and laminating artificial leather
According to the formula requirements, the resin, plasticizer and other compounding agents are measured. Put it into the kneading machine and mix it evenly. Then, after plasticizing in the internal mixer or extruder, send it to the two-roll or four-roll calender to calender it into a film of the required thickness and width, and laminate it with the preheated base cloth, and then emboss and cool it to get the finished product.
4. Extrusion lamination method artificial leather
Mix the resin, plasticizer and other compounding agents evenly in the kneading machine, and then plasticize them. Then, extrude it into a film of a certain thickness and width through an extruder, and then laminate it with the preheated base cloth on the two-roll setting machine, and then preheat, laminating, embossing, and cooling. The finished product is obtained.
5. Round screen coating method artificial leather
Use a scraper to apply the emulsion polyvinyl chloride paste resin prepared in the formula to the cloth base through a round screen to produce artificial leather.
6. Wet method artificial leather
This method is for the dry method. Its definition can be found in polyurethane artificial leather. This method is suitable for the production of wet polyurethane artificial leather, polyamide artificial leather, etc.
3.4 Classification by Use
Artificial leather can be divided into two categories according to its use: civil and industrial.
Civilian leather includes: leather for shoes, leather for clothes, leather for boxes, leather for bags, leather for handbags, leather for gloves, leather for furniture, etc.
Industrial leather includes: leather for vehicles, leather for floors, etc.
V. How to Distinguish Different Artificial Leather
4.1 Gasoline Soaking
Put a small piece of fabric in gasoline for half an hour, and then take it out. If it is PVC artificial leather, it will become hard and brittle, and if it is PU synthetic leather, it will not become hard and brittle.
4.2 Burning Method
When burning, PVC artificial leather will emit green smoke, while PU synthetic leather is only black smoke.
VI. Artificial Leather Price
Generally speaking, the effect of microfiber PU synthetic leather>PU artificial leather>PVC artificial leather, and the price is also.
However, there are differences in products produced by different manufacturers. Products produced by small factories and small workshops are of poor quality and low price.