USE OF SIDE-BY-SIDE BICOMPONENT FIBERS
Side-by-side fibers are generally used as self-crimping fibers. There are several systems used to obtain a self-crimping fiber. One of them is based on different shrinkage characteristics of each component. All commercially available fibers are of this type. There have been attempts to produce self-crimping fibers based on different electrometric properties of the components; however, this type of self-crimping fiber is not commercially used. Some types of side-by-side fibers crimp spontaneously as the drawing tension is removed and others have "latent "crimp, appearing when certain ambient conditions are obtained. Some literature mentions, "reversible "and "non-reversible" crimp, when reversible crimp can be eliminated as the fiber is immersed in water and reappears when the fiber is dried. This phenomenon is based on swelling characteristics of the components. Several factors are crucial to the fiber curvature development: The difference in the shrinkage between the components, the difference between modulus of the components, the overall cross-sectional fiber shape and individual cross-sectional shapes of each component, and the thickness of the fiber.