Types and scope of application of leather finishing agents

Modified polyurethane leather finishing agent

It has excellent properties of both polyurethane and epoxy resin, and has good adhesion and elasticity. It is used for skin coating of electrical materials, leather products, nylon conveyor belts, rubber products, wood products, and metal materials. It is more suitable for soft elastic products, bamboo, rattan, conveyor belts, tapes, belts, leather products, rubber and plastic materials, etc. It is superior to the existing domestic top coatings, especially for balls, leather jackets, luggage, etc., reaching the advanced level of similar foreign products. In terms of water resistance and wear resistance, it is superior to that of polyacrylate and its modified finish. It can make the product beautiful, smooth and prolong the service life.

Scope of application

Polyurethane is a polymer compound formed by the action of polyisocyanate and polybasic compound. Due to the existence of ammonia hydrogen bonds between macromolecules, its polymer has good strength, wear resistance, solvent resistance and other properties, making polyurethane in rubber. , coatings, adhesives, synthetic fibers and other fields have a wide range of applications, especially as a finishing agent used in high-grade leather.

In recent years, with the strengthening of environmental protection awareness and measures, the research and development of water-based polyurethane leather finishing agents have been highly valued, and cationic water-based polyurethane finishing agents have been widely studied at home and abroad for their unique properties. The cationic water-based polyurethane primer introduced in this paper has a certain filling performance, and the back cover can not only produce better adhesion with the negatively charged leather blank, but also have a strong linking effect with the anionic top coating, so that the The leather feels softer and fuller, further improving the leather quality.

Modified Acrylic Leather Finish

Acrylic resin is currently the most widely used type of leather finishing agent material in the world, and its annual output accounts for about 70% of leather finishing agents. From the perspective of production cost, process and comprehensive performance, acrylic resin as a finishing material Chemical materials can be described as having many advantages, but nothing is perfect in the world. Since 1987, the American Rohm and Hass company has successively developed new products, the second-generation acrylic resin (sGA), which has made a breakthrough in hot-bonding and cold-brittleness. Subsequently, my country has also achieved certain results in the modified surface of acrylic materials. However, most of its development methods are to introduce functional monomers and acrylic monomers for multi-component copolymerization, graft copolymerization, or external crosslinking agents to change the linear structure into a network structure, thereby improving the heat and cold resistance of the coating film. The technical means remain at the level of molecular structure. Although the hot-sticky cold-brittleness performance has been improved, it is still insufficient. Such finishes are still not effective in northern regions.

protein binder

The main ingredient is casein. Since the original casein (protein) is easy to deteriorate, the protein adhesives used now are all modified. It can be firmly combined, has clear natural grain of leather, and has a leather touch. It can maintain the hygienic properties of leather such as good water vapor permeability.

Nitrocellulose

Cellulose esters are mainly used as brighteners for the top layer of leather, and most of them are nitrocellulose, namely nitrocellulose (NC). High-gloss, dark-gloss, silky, waxy, colorless, transparent, etc., the main characteristics are that the coating is brittle, not resistant to aging, poor cold resistance and poor air permeability after film formation.

Technical characteristics of leather finishing agent

The leather finishing additive is emulsified with a special neutral nonionic emulsifier, which is resistant to acid, alkali, hard water, strong water solubility, high solid content, good dispersibility, and stable emulsion. Shortcomings, and leather finishing additives can be diluted with water in any proportion without delamination, demulsification, and agglomeration. The application of leather finishing additives in leather mainly plays the role of filling coating, improving coating feel, wear resistance, anti-sticking and increasing gloss. Leather finishing additives are the main additives for finishing high-grade leather, which can give the leather special brightness and waxy feeling. Leather finishing additives can be used for the bottom layer, middle layer and top layer finishing of leather respectively. Leather finishing additives can also be used in combination with finishing agents with different ionic properties. The leather finishing additive has good water solubility, stable emulsion, no delamination and no floating wax after long-term storage. It can be applied to the finishing of all kinds of leather, the leather after finishing has a soft and natural luster, feels plump and moisturizing, and can improve the friction resistance of the leather surface.

Tianshi specializes in the production of waxes for leather finishing agents, welcome to inquiry.