What are neps, seed coat neps and trash? Why is it a problem for the spinner?

  • Neps deteriorate the appearance of fabrics considerably. Therefore, it is the intention of spinning mills to keep the nep content of cotton fibers and the formation of neps under control.
  • Neps do not exist in cotton bolls. Neps are produced by ginning, opening and cleaning of cotton. We distinguish 2 types of neps:

The fiber neps which are defined as an entanglement of fibers.
They are formed under mechanical treatment

The seed coat neps are fragments of cotton seeds with remaining fibers.
They are mainly produced in ginning when the fibers are separated from the cotton seeds


Solution - Measuring principle

A sliver of about 25 to 30cm length is automatically opened and transformed into a thin homogeneous web by a carding cylinder (without card tops in order to avoid any removal of fragments!). With the FIBERMAP image analysis of the web by more than 100 images the fragments (neps, seed coat neps and trash) are captured by a video camera. A light source illuminates the fragments and allows differentiating in various types and sizes.

Results: By inspecting the fiber web the different fragments are recognized and classified into 5 classes for count/gr and for the average size.



Identification of cotton fiber impurities. Classification according to type and size.


Fiber Classing

  • Cotton classing
  • Stickiness measurement and grading
  • Automated testing


Data monitoring for fiber and yarn testing

  • Value-added reports
  • Data for quality management
  • Customer specific sample identification