New Developments in the Industry: Overcoming Nanofiber Research Processes Using Melt-Blown Technology

Melt-blown technology is a crucial method for large-scale production of ultrafine fibers. Its principle is that polymer materials are extruded through spinnerets, and then further stretched under high-temperature and high-velocity airflows to form ultrafine fibers. The application of ultrafine fibers in melt-blown nonwovens is unparalleled by other products manufactured using a single nonwoven technology. Thanks to the availability of various raw materials that can be continuously used for melt-blowing, melt-blown nonwoven technology has developed rapidly, driving the growth of the melt-blown nonwoven industry.

Owing to their small diameter, large specific surface area, and small pores in the fiber web, melt-blown nonwoven products exhibit excellent particle capture and thermal insulation properties. They also possess unique capillary action and breathability—preventing the penetration of water and blood while allowing the passage of vapor. For these reasons, such products are widely used as filtration materials, thermal conductive materials, sanitary materials, and medical materials.

Melt-blown nonwoven technology originated in the early 1950s. The U.S. Naval Research Laboratory melted polyamide fibers, extruded them through a special spinneret, and simultaneously used high-velocity hot air to stretch the polymer melt into fine streams, successfully developing the melt-blown technology for ultrafine polyamide fiber nonwovens. Since then, the technology has entered a stage of industry-academia-research cooperation and development.

According to priority country information, an analysis of the countries/regions where melt-blown technology patents are filed shows that the number of U.S. patents accounts for 47% of all patents, giving it an absolute leading position; Japan ranks second, accounting for 22%. It is worth noting that melt-spun fabrics capable of producing fibers with a diameter of less than 5 micrometers are the prototype of modern melt-blown nonwovens.

In the early 1990s, when the United States and Japan already held a large number of melt-blown technology patents, China began to file relevant patents. It was not until melt-blown technology entered a research boom that the number of China's related patents started to grow rapidly. It can be seen that China once lagged relatively behind in the field of melt-blown technology, but in recent years, China's melt-blown technology has also achieved rapid development.

With the rapid development of industry and the increasing global awareness of environmental protection, the market scale of melt-blown nonwovens has been expanding. Meanwhile, the continuous emergence of new materials, new processes, and new melt-blown nonwoven products has further expanded their application fields. As indicated by the aforementioned patent analysis, the current main research focus of melt-blown technology is on product development, with the research results mainly applied to filtration materials, absorbent materials (including water-absorbing, oil-absorbing, and sound-absorbing types), and medical materials, while research and development on melt-blown equipment is relatively limited. In the field of melt-blown fiber preparation, the current research directions include the preparation technologies of bicomponent melt-blown fibers, layered nonwovens, composite nonwovens, and elastic nonwovens. According to literature reports, melt-blown technology is expected to achieve significant breakthroughs and development in areas such as spinning melt composites, bicomponent melt-blown technology, electret melt-blown nonwovens, and the improvement of melt-blown equipment in the future.