There is no international consensus. The US PET Neighborhood Committee defines fibers with a monofilament fineness of 0.3~1.0 dtex as superfine fibers, Japan defines fibers with a monofilament fineness below 0.55 dtex as ultrafine fibers, and Italy defines monofilaments as monofilaments. Fibers with a fineness of 0.5 dtex or less are defined as ultra-fine fibers, […]

