17 Polyimide resin fibers for nonwoven fabrics used in insulation materials, electronic materials, and filters; chemical fibers, not for textile use; rock wool; carbon fibers, other than for textile use; chemical fiber yarn and thread, not for textile use; threads of plastic materials, other than for textile use; fiber fabrics for electrical insulation, heat insulation, and soundproofing; glass fibers for electrical insulation, heat insulation, and soundproofing; asbestos fibers; plastic fibers, other than for textile use.