The emergence and evolution of filter paper-particularly high-efficiency air filtration media-have been closely linked to the demands of the military and electronics industries. Asbestos fiber filter paper, used as the smoke-filtering layer in military gas masks, appeared as early as the end of World War I. A patent for the use of glass fiber media in air filtration was granted in the United States in October 1940. During the 1950s, extensive research into the manufacturing processes for glass fiber filter paper in the U.S. led to significant improvements and advancements in air filtration technology.
By the 1970s, HEPA filter paper made from ultrafine glass fibers achieved a filtration efficiency of 99.999% for 0.3-micron particles. Since the 1980s, through tireless effort, Chinese researchers have successfully developed glass fiber HEPA and ULPA filter papers, reaching-and in some respects surpassing-the advanced standards of similar products worldwide.
Currently, the rapid growth of sectors such as industry, environmental protection, pharmaceuticals, and food processing, alongside the rise of emerging industries like new energy vehicles and advanced materials, has driven a continuous increase in the demand for filter paper. This trend fosters ongoing technological innovation and product upgrades. While glass fiber media remain the dominant choice for high-efficiency air filtration globally, new materials-such as membrane and electrostatic-enhanced media, as well as high-temperature resistant options (e.g., glass fiber/inorganic membrane composites, metal fiber, and ceramic fiber media)-are also being developed to meet increasingly stringent filtration requirements.
