Using the HVI to Characterize within Sample Variation in Cotton Fiber Length.

Cotton fiber is an industrial raw material used in the manufacture of high value ring-spun yarns. Natural variation in cotton fiber attributes can lead to imperfections in spun yarn quality. Cotton fiber length is an important processing parameter to produce spun yarns, but it is not just the long fibers that are important. The complete within sample distribution of cotton fiber length has an impact on processing performance and yarn quality. The High Volume Instrument (HVI) provides the most commonly used cotton fiber length parameters used in marketing and research, Upper Half Mean Length (UHML) and Uniformity Index (UI). However, HVI length measurements are based on the fibrogram and do not completely characterize within sample variation in fiber length. The Advanced Fiber Information System (AFIS) is an individual cotton fiber tester that can measure the complete within sample variation in fiber length. The AFIS reports within sample variation as a relative frequency histogram called the AFIS length distribution. A large set of samples from commercial bales were used to evaluate the HVI length measurements and determine the extent to which HVI length parameters characterize variation captured by the AFIS length distribution.