Polyester Fiber, KODEL
                This is a sample polyester fiber from the sample-set
                  provided by Textile Fabric Consultants, Inc.
                  Kodel is a trademarked product of the Eastman Chemical Company. The high
                  birefringence and small diameter of the fiber
                  results in the high order interference colors seen here. Larger diameters would
                  appear in high order white.
                
              
              
                Transmitted Crossed Linear Polarized Light
                
Definition/Function:
                Polyester fiber is derived from terephthalic acid. It is formed into a fiber by
                extruding the heated polymer through a
                spinneret. This results in the fiber taking the cross-section of the spinneret.
                Polyester fiber can be round or any other
                desirable extruded shape.
                Significance in the Environment:
                This is a common clothing fiber.
                Characteristic Features:
                Rayon fiber has a refractive index along its length of about 1.71 to 1.73 and
                perpendicular to its length of about 1.53
                to 1.54. It has a birefringence of about 0.18 and a positive sign of elongation. It
                tends to exhibit a smooth, regular
                surface along its length depending on its cross-section of the fiber. Extreme shapes,
                such as heptalobate types, can
                result in an irregular appearance along the length as the fiber twists or bends.
                Associated Particles:
                References:
                DuPont Company Techinical Bulletin X-156: IDENTIFICATION OF FIBERS IN TEXTILE MATERIALS,
                December 1961. 
                http://en.wikipedia.org/wiki/Polyester