The Structure And Properties Of Superfine Fiber Synthetic Leather

The warp knitting bases which are made of EHDPET/COPEET sea-island composite filaments of different specifications, high shrinkage polyester filaments, Polyurethane filaments or ordinary polyester filaments. Impregnating in solvent-type PU, making alkali peeling, researching the products’characteristics in each stage of the process, and studying the influence of different types and specifications yarns on structure and properties of the knitted fabrics. Designing different impregnated-Alkali peeling conditions for base, after processing, concluding the optimal condition by the final products’structure and performance tests. And then comparing advantages and disadvantages of properties between the two types of impregnated-Alkali peeling PU fabrics.The results show that the different types of yarns have strong influence on thickness, density, fullness and the ability to resist deformation of knitting fabrics. Compared with the base, impregnated-Alkali peeling PU fabrics are easier to deform but have better recoverability and surface evenness. After knitted fabric with Waterborne Polyurethane, low heat microwave is the best drying condition; and with higher PU concentration and lower roller pressure, the base has higher quantity of PU, and has lower decrement rate of impregnated-fabrics; the final product’s is difficult to be bend and tensile, but easy to recover and more fluffy. The best impregnating condition is:PU concentration is 20%～25%, the concentration of the thickener is around 0.8%, roller pressure is around 2～3MPa, temperature of PU is around 50℃. When alkali concentration is about 25%,temperature is 95℃, alkali treatment is about 30 mins, bath ratio is 1:50, the sea-island fibers are fully splitted without damage; With the increase of alkali concentration, temperature and treatment time, knitted fabric are difficult to be tensile and bend, and compression sense of fullness and resilience of it increase first, then slightly decrease. Compared two kinds of PU microfiber leather samples, water-based PU leather is more fluffy and has better air permeability, but stiffer; Solvent-based PU leather has good bending and tensile ductility.