BI component fiber

If two different polymers are extruded together to form a fiber, so-called bi-component fibers are obtained. Depending on the desired property profile, both the polymers used and the geometric arrangement of the polymers can be varied. Our bi-component fibers have a sheath-core geometry. A high-melting PET core is surrounded by a sheath made of a polymer with a lower melting point, such as PE or Co-PET. When used as a binding fiber, the sheath polymer can be melted during the thermal bonding of a nonwoven without softening the fiber core. As a result, the softened sheath polymer flows to fiber crossing points and bonds them after cooling, creating a solid network of defined porosity.

Pros and cons
BI component fiber Properties


  • Strong fiber bonding and high strength of the end product
  • Porosity can be controlled by the binding process
  • Good workability
  • No use of liquid binders


  • Limited recyclability
  • Nonwoven thermally stable only up to the softening range of the sheath polymer

BI component fiber
Manufacturing process

Bi-component fibers are produced by melt spinning. The design and geometry of the spinneret, as well as the separate supply of the two polymer components to the spinneret, are crucial for high-quality production. The polymer components only come into contact with each other after or shortly before leaving the spinneret. In subsequent process steps such as stretching or applying the finish, the fibers are further tailored to the respective application.

Order our BI component fiber Sample box

Contact our fibre experts and discover our extensive STW sample box with numerous raw material samples, personally tailored to your needs and requirements.

Order BI component fiber sample box

technology and
quality of the fibre

State-of-the-art laboratory facilities, quality management according to ISO 9001:2015, energy management according to ISO 50001:2018 and last but not least the high demands on our own work ensure the high quality standards of our BI component fiber. See for yourself.

If you want to know more about the technology and quality of our BI component fiber If you want to know, just get in touch with us. We would be happy to advise you comprehensively and help you with our know-how.

You are looking for the perfect BI component fiber for your application or have an exact requirement profile, which the used BI component fiber must fulfill?

Then you are exactly right, as a technology leader in the field of fibre development and production, we offer you individual solutions and manufacturing processes that ensure constant and reproducible fibre quality.



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