Sheet of microfiber assembly, and method and apparatus for making the same

摘要

Disclosed is a sheet-like assembly of fibers having small diameters, which can be used as a filter having an excellent ability to filter an oil mist. Specifically disclosed is a sheet-like assembly (2) of fibers (1) having small diameters, wherein each of the fibers (1) has a fiber diameter of 3,000 nm or less and comprises a mixture of a water-insoluble and alcohol-soluble acetalized polyvinyl alcohol resin and a water-insoluble and alcohol-soluble fluororesin.