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KB SEIREN, LTD. has developed “Gradio®”, a polyphenylene sulfide fiber with superior heat resistance, by using its original technology. For industrial applications attracting increasing attention, KB SEIREN proudly offers Gradio® as a sophisticated fine-denier engineering plastic fiber, while further utilizing its unique technologies of fine-denier fiber spinning and composite fiber spinning to advance reduction of total fiber fineness, as well as single filament fineness, to the extent never before possible.


Technical Description

Fineness (total fiber fineness, single filament fineness) enhanced with original technologies of KB SEIREN

A) Filaments
Monofilaments: 13 dtex/1f (filament diameter: 35 μm), 33 dtex/1f (filament diameter: 56 μm)
Multifilaments: 33 dtex/12f, 56 dtex/24f, 84 dtex/24f, 167 dtex/48f, 220 dtex/48f

B) Staple fibers
Regular type: 1.1 dtex X 3–5 mm and various others, 1.7 dtex X 3–5 mm and various others
Split type: 0.2 dtex X 3–5 mm and various others
Binder type: 1.7 dtex X 3–5 mm and various others

End Products

Filaments, staple fibers, fabrics (woven, knitted, nonwoven), braided cords/sleeves, paper


Filters (mesh and various others), membrane materials (separation membrane substrates, spacers), insulating materials, separators, automotive materials, etc.