Microfiber leather, that is, microfiber PU synthetic leather, is a green and environmentally friendly material made through a series of fine processes. It uses microfiber staple fibers as raw materials, and forms a non-woven fabric with a three-dimensional structural network through a combing and needle punching process, and then undergoes wet processing, PU resin impregnation, alkali reduction, leather grinding and dyeing and other processes to finally create microfiber leather. Among them, the island-type microfiber has become the most widely used raw material in China due to its unique structural characteristics. This fiber cleverly disperses one polymer in another polymer to form a distribution state of "island" and "sea". During the production process, it presents the fineness of conventional fibers, but by dissolving the "sea" component, a clustered microfiber bundle can be obtained, which provides a new breakthrough for the production of microfiber leather.
After the "sea" component is dissolved by toluene or alkali solution, the original single fiber will split into dozens of finer fibers, whose fineness depends on the number of "islands", but can reach tens of the fineness of the original fiber. At present, there are two main production processes for sea island microfiber: one is the toluene reduction process with unfixed islands, and the other is the alkali reduction process with fixed islands. Both processes can be effectively recycled during the treatment process, but will inevitably produce a small amount of three wastes, and there are risks of toluene residue and odor.
