The retanning agent is a chemical material used for leather retanning. Generally, it includes main sputum, mainly refers to tanning materials developed for retanning purposes, such as acrylic resin retanning agent, amino resin retanning agent, oxazolidine oxime agent and the like.
Reclamation is an important process in the modern tanning industry and is known as the "golden technique" in leather processing. For light leather, reclamation is almost an essential process. Commonly used retanning agents can be divided into inorganic bismuth agents, organic bismuth agents and metal organic bismuth agents. Subdivision can be divided into inorganic salt retanning agents, vegetable tannins, aromatic synthetic tanning agents, aldoximes, acrylic resin retanning agents and the like. Acrylic monomers have a wide variety of resources, rich in resources, and large development space for acrylic resins, so they have broad application prospects in the leather industry.
With the continuous improvement of synthetic technology and the rapid development of the tanning process, it is hoped that a multi-functional high-quality resin tanning agent with softness, toughness, super-water resistance, anti-fouling and flame-retardant can be developed, which is necessary and inexpensive. The acrylic resin retanning agent is appropriately modified. Prabhu uses a cationic polyurethane prepolymer and methacrylic acid to form a diene compound, and then grafts with sulfated castor oil and methacrylic acid to obtain a good retanning agent. Silicone or epoxy resin modified acrylic resin cakes have appeared in China. Therefore, it is foreseeable that more and more acrylic retanning agents will be available soon to meet the development of the tanning industry.