Analysis on the past and present production methods and varieties of artificial leather
Artificial leather artificial leather artificial look, feel like leather (see leather) and can replace the plastic products used. It is usually made of a fabric-based compound coated with a synthetic resin and various plastic additives (see plastisol processing). In the early 20th century, nitrocellulose varnish made of nitrocellulose sol coated fabric was the pioneer of artificial leather. In the 1930s, industrialized production of PVC opened up new raw material resources for artificial leather and promoted the development of artificial leather production. The paste made of polyvinyl chloride added with plasticizers, stabilizers, etc. is easy to be colored. After the coating is gelatinized, it can be made into a variety of products similar in appearance to leather by printing, embossing or embossing and printing. . Although its gas permeability and moisture permeability are not as good as natural leather, it has certain strength and wear resistance. It is easy to produce, rich in raw materials, uniform in product quality, easy to cut, light in weight, water resistant and low in cost, so it is widely used in production. Clothing, shoes, hats, bags, furniture, accessories and various industrial accessories. With the development of plastic varieties and processing technology, artificial leather has formed a variety of products. In addition to polyvinyl chloride, the coating material is also made of polyamide, polyurethane, polyolefin, or the like. There are also a variety of base fabrics, such as plain cloth, canvas, knitted fabric, raised fabric, and non-woven fabric. The production of artificial leather of different varieties and colors is also distinguished from the coating and gelling methods of the base fabric surface, as well as the finishing process, such as the order of embossing, printing, surface treatment, and the composition of the surface treatment agent. Production includes base fabric treatment, rubber preparation, coating, lamination, gelation, surface treatment, embossing, cooling, coiling and other processes. There are four main production methods. The direct coating method directly coats the rubber material on the pretreated base cloth with a doctor blade, and then gels and plasticizes it into a plasticizing box, and then embossing, cooling, etc., to obtain a finished product. This method can produce ordinary artificial leather, film artificial leather and foamed artificial leather of various cloth bases. Transfer coating is also known as indirect coating. Applying the paste to the carrier (release paper tape or stainless steel belt) with a reverse roll or a doctor blade, after gelation, and then laminating the cloth base on the gelled material layer under tension, and then After plasticizing, cooling and stripping from the carrier, and then post-treatment, the finished product is obtained. This method is suitable for the production of knitted fabrics or non-woven fabric based foam artificial leather and ordinary artificial leather. According to the formulation requirements, the resin, plasticizer and other compounding agents are metered into the kneading machine and mixed uniformly. After being refined by an internal mixer and an open mill or extruder, they are sent to three rolls or four. Roll calender (see plastic mechanically calendered into a film of the required thickness and width, and adhered to the pre-heated base fabric, and then embossed, cooled to obtain the finished product. This method can produce a variety of artificial leather of different fabrics. To improve the bonding effect between the base fabric and the film, a layer of adhesive is often applied to the base fabric. Extrusion paste method, the resin, plasticizer and other compounding agents are uniformly mixed in the kneader. After being refined, the film is extruded into a film of a certain thickness and width by an extruder, and then preheated on a three-roll setting machine. The base fabric is laminated, and then the finished product is preheated, filmed, embossed, and cooled. This method is used to make thicker products such as floor leather, conveyor belts, etc. The varieties are mainly PVC artificial leather, in addition to polyamide, polyurethane, polyolefin artificial leather. There are 3 types of PVC artificial leather: 1 ordinary artificial leather, also known as non-foamed artificial leather. It is made of flat cloth, canvas and recycled cloth, and is directly coated. Since the coating is dense and the paste can penetrate into the pores of the base fabric, the finished product feels hard and wear-resistant. Mainly used in the production of wear-resistant bags, construction and industrial accessories. 2 foamed artificial leather. Usually, the knitted fabric is used as a base, and the surface layer paste contains a foaming agent and an auxiliary agent thereof, and foams to form a microporous structure during gelation, thereby being light in quality, full in hand and soft. Produced by transfer coating. Used for making gloves, bags, bags, clothing and furniture. 3 suede artificial leather. Commonly known as artificial suede. It has a wide variety and a variety of production methods. The microporous surface layer of the artificial leather after gelation can be made into a surfaced suede by grinding with a sand roller. The coated layer is raised and stretched by a raising roller to obtain a crimped suede. Suitable for use as a toe cap and edging material for sports shoes. A soluble salt (such as a salt) is added to the coating paste, and after the gelation, the salt is dissolved by using water, so that the surface layer is microporous and has a suede feeling. Using the electrostatic flocking method (see plastic processing), a synthetic fiber lining of 0.5 to 1 mm length is planted on a polyvinyl chloride artificial leather coated with a binder to obtain a flocked leather, which is suitable for making bags and decorations. Product. Stud,Blind Standoff,Self Clinching Standoff,Thru-Hole Threaded Standoffs,Nut Standoff Dongguan Tiloo Industrial Co., Ltd , https://www.sales-fastener.com