TEIJIN has developed ultra-fine fiber of a diameter about 1/500th of human hair from 7 different polymers. By applying the spinning technology established for polyester, TEIJIN has established a stable processing technology to produce ultra-fine fiber of a diameter about 1/a few 10th of available ultra-fine fibers from various polymers including polylactic acid and nylon. TEIJIN plans to develope various nonwovens for a filter adsorbing specific substances or a protection material with high heat resistance.
Newly developed 7 fibers have their own characteristics. Poly(ethylene naphthalate) is characterized by its high electric insulation and high heat resistance. Poly(trimethylene terephthalate) exhibits a good shape recovery. Polyethylene and polypropylene are alkali-resistant. Polycarbonate is easy to be molded. Polylactic acid is bio-degradable. Nylon is hydrophilic and excellent in abrasion resistance. A diameter of each fiber can be controlled in the range from 200 nm to 700 nm.

JCFA News Letter (No.8) June, 2014/Japan Chemical Fibers Association