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SIDERIA is a nylon/polyurethane composite fiber created with conjugation technology, one of the specialties of KB SEIREN. It self-crimps when treated with heat, and thereby possesses moderate stretchability.

Product Features

Neat Knitted Surface

Heat treatment provides SIDERIA with even and uniform spiral crimps, ensuring neat and smooth knit surface effects.

Moderate Stretchability

SIDERIA is received well in Japan and abroad for its moderate tightness, which is unavailable with conventional covered yarns, as well as for its "barely-there" soft fit. It minimizes sultriness during hot and humid summer season.


Being a bicomponent yarn of nylon and polyurethane, SIDERIA guarantees an extra-thin and superbly transparent knit which is scarcely achieved by conventional covered yarns.

Crisp Feel

SIDERIA has excellent elastic recovery as well as low stress-induced stretchability. Even low count filament yarns made of SIDERIA are soft and crisp to the touch, instead of having rough texture.


Care Instructions