In the textile industry, a tow (or hards) is a coarse, broken fibre, removed during processing flax, hemp, or jute[1] and separated from the shives. Flax tows are often used as upholstery stuffing and oakum. Tows in general are frequently cut up to produce staple fibre. The very light color of flax tow is the source of the word "towhead", meaning a person with naturally light blond hair.[2]

Caulking tools with tow

Composite materials


In the artificial fibre and composites industries, a tow is an untwisted bundle of continuous filaments, in particular of acrylic, carbon fibres, or viscose rayon. Tows are designated either by their total tex (mass in grams per 1000 m length)[3] or by the number of fibres they contain.[4][5] For example, a 12K tow contains 12,000 fibres.[6][7]

Spread tow fabrics are woven sheet materials, used for composite layup, where the warp and weft are flat tows, rather than spun yarns, in order to provide the maximum strength as a composite.


  1. ^ "Tow". Glossary of Colonial Terms. History Online. September 15, 2007. Archived from the original on 2007-09-15.
  2. ^ "Towhead". Online Etymology Dictionary. Retrieved November 28, 2016.
  3. ^ Vasiliev, Valery V.; Morozov, Evgeny V. (2013). Advanced Mechanics of Composite Materials and Structural Elements (3rd ed.). Elsevier Science. p. 15. ISBN 978-0080982670.
  4. ^ Rosato, Donald V.; Rosato, M. G.; Rosato, Dominick V., eds. (2000). Concise Encyclopedia of Plastics. Kluwer Academic. p. 278. ISBN 0792384962.
  5. ^ National Research Council of the National Academies (2005). "High-Performance Fiber Technology: Carbon Fibers". High-Performance Structural Fibers for Advanced Polymer Matrix Composites. Washington, D.C.: National Academies Press. p. 7. ISBN 0309096146.
  6. ^ "Carbon Fiber- What is K?". March 29, 2015. Retrieved December 5, 2018.
  7. ^ "HexTow® Carbon Fiber" (PDF). Hexcel (General Product Information of carbon fiber tow manufacturer). 2008. p. 7. Retrieved December 5, 2018.