Review of "Graphs, Networks, and Algorithms (second edition) by Dieter Jungnickel", Springer-Verlag 2005

Hollow filaments having longitudinal grooves and ridges that are readily split along the grooves and are especially adapted for use in a flocking process to form flocked products with a surface similar to suede. The hollow filaments have a denier of about 0.8 to about 3.35 and have a void area of 15 to 30% of the total area of the cross section of the fiber.