Development Status And Gaps Of Key Non Woven Products Technology

In the past ten years, my country's non woven products industry has developed rapidly and has become the world's largest producer and trader of non-woven materials. Demand-driven capacity growth is also driving innovation in nonwoven processes. At present, my country's technological innovation in spunmelt production lines, bicomponent spunbond spunlace nonwovens and other products has made obvious progress, reaching the international leading level. This paper introduces the development status of the key production process of non-woven products and the gap with foreign technologies.

1. Melt spinning process of non woven products

The melt spinning process is the most widely used process in my country's non-woven fabric industry, and its output accounts for nearly half of the total output of non-woven fabrics. However, there is still a big gap between the domestic technical level and the international advanced level. In recent years, bi-component and multi-component composite spunbonding has become the main direction of advanced technology development. Developed countries have been able to manufacture products with various bi-component composite spun fiber cross-sectional structures, and in three-component and four-component composite spinning A breakthrough has been made in fiber technology. Although my country has developed two-component composite spunbond products such as hot rolling and spunlace, the large-scale two-component production lines basically need to be imported from abroad, and the development still needs to learn from foreign technology and use authorized patents. product.

2. Flash spinning process of non woven products

The flash spinning process is the "top process" of non-woven fabric technology, with ultra-high spinning speed and less spinning solvent (compared with dry and wet methods); the fibers produced by this process have the advantages of high strength and light weight. , with a diameter of 400 to 1000 nm. At present, DuPont is the only company in the world that has mastered the technology and product industrialization capability, and "TYVEK (Tyvek)" is the trade name of its products. Subject to the foreign patent protection system, the domestic flash spinning process has been in the exploratory stage. Textile colleges and a few equipment manufacturing enterprises represented by Tianjin University of Technology have carried out some research and industrialization exploration in this area. Some phased achievements have also been made in terms of technology and equipment, and there is still a long way to go before industrial application. There are only a handful of enterprises and personnel who have carried out in-depth research on the selection of the main solvent in the solvent preparation for flash spinning, a key step in the flash evaporation process.

3. Cellulose fiber spinning process for non woven products

Because of its biodegradability and biocompatibility, cellulose mesh is widely used in the field of biomedicine. The cellulose fiber spinning process represented by Lyocell melt/melt blown web technology has made great progress abroad as early as the late 1960s. Lenzing (Lenzing) is a typical representative and technology leader in this field. At present, my country has a complete set of domestically produced equipment, technology, safety, automation control and engineering technology systems for Lyocell fiber, and has the technical capabilities of engineering design, engineering implementation and rapid industrialization promotion. In 2018, China Textile Research Institute successfully developed a complete set of integrated technology and equipment for large-scale thin-film evaporation, continuous dissolution and defoaming, dry-spraying and wet-spinning technology and equipment for high viscoelastic spinning dope, and NMMO solvent low-temperature evaporation, concentration and recovery technology and Complete equipment. At present, a Lyocell fiber production line with an annual output of 15,000 tons has been built, and related non-woven fabric products have been used in clothing, home textiles, industrial textiles and other fields.

As the market potential of non-woven products attracts more and more attention in the industry, the spunbond process, flash process and melt-blown process will continue to develop in the direction of fiber fine denier and micro-denier; The requirements for the development of functionalization and high value-added should prompt enterprises to pay more attention to the combination innovation between different processes. While improving spinnability, enhancing practicability and reducing costs, adding functionality, based on different non-woven fabrics. Technological innovation is carried out according to the needs of the application field and its own characteristics.