关键词: 水性聚氨酯, 仿超纤革, 手感, 透气性, 耐光色牢度

Abstract: Natural leather is widely used because of its high strength, good elasticity and excellent hygienic properties. However, with the growth of population, rising demand and increasing awareness of environmental protection, the development of high-performance synthetic leather has become a trend. Microfiber synthetic leather (hereinafter referred to as microfiber leather) is developed on the basis of analyzing the structure of natural leather. It is made of microfiber three-dimensional non-woven fabric combined with polyurethane (PU). Specifically, immersion is the critical manufacturing step. The PU solution is immersed into the interstitial spaces of the base fabric through the calendering process. After the PU is cured, the base cloth forms an organic whole structure and gives the leather-like texture. The properties of the PU used directly affect the quality of the super fiber leather. Compared with natural leather, PU synthetic leather has diverse sources of base materials, less pollution during processing and lower production costs. Through continuous advancements in material science and processing technologies, microfiber leather has internal structural characteristics and sensory properties similar to those of real leather and surpasses natural leather in wear resistance and mechanical performance. At the same time, it has many excellent properties such as strong tear resistance, excellent resilience and pleasant tactile sensation, so it is widely used in clothing, automobiles, military, among others. However, because the common base fabric of microfiber leather is non-woven, its price is generally higher, while the microfiber warp-knitted fabric is more affordable and better suited to enterprise production efficiency. Moreover, the prepared microfiber-like leather boasts superior hand feel and other properties. Consequently, it offers advantages such as a streamlined production process, reduced energy consumption and lower costs while delivering excellent hand feel and garment performance. In this paper, a yellowing-resistant waterborne polyurethane was selected as the raw material. The sea-island fiber warp-knitted fabric was treated via padding, pre-baking and baking. The hand feel, air permeability and light fastness of the obtained waterborne polyurethane imitation microfiber leather were tested, and different types of waterborne polyurethane and base cloth were selected to determine the best concentration, compounding ratio and base cloth of waterborne polyurethane. The results show that when the dilution ratio is twice, the blending ratio of waterborne polyurethane SX-5003∶SR-5912 is 3∶1, and the base fabric is Italian velvet, the hand feel rating of the imitation microfiber leather reaches 4.0, the air permeability is 26.28 mm/s, and the light fastness grade reaches levels 4–5. The waterborne polyurethane imitation microfiber leather developed through this study has excellent hand feeling and light color fastness. It is very environmentally friendly, contains no harmful substances and helps control the production cost of enterprises, thereby enhancing corporate profitability. Compared with the microfiber leather, the imitation microfiber leather studied in this paper is more economical, energy saving and environmentally friendly. Notably, it demonstrates superior operational performance and is expected to be applied in the home industry.

Key words: waterborne polyurethane, imitation microfiber leather, hand feel, air permeability, color fastness to light