USE OF CORRELATION AND REGRESSION ANALYSIS IN ESTIMATING RELATIVE IMPORTANCE OF FIBER PROPERTIES AFFECTING YARN HAIRINESS IN SOME EGYPTIAN COTTON GENOTYPES.

Yarn hairiness can be desirable or undesirable, depending on the application for which the yarn is being used. Hairy yarns provide good heat retention and a softer hand (feel) for finished fabrics, and except for a few special cases, when there is an excessive degree of hairiness, it may be an undesirable property in yarn and probably cause serious problems in both yarn production and in subsequent textile processes. This search was carried out to investigate relative contributions of the most important fiber properties i.e. fiber length (upper half mean) (m.m), fiber strength (g/tex), micronaire reading, short fiber content (%), elongation (%) and uniformity index (%) which correlated with yarn hairiness using four Egyptian cotton genotypes namely; Giza 92, Giza 88, Giza 93 and G 84 (G70 x 51B) s 62 spun using combed ring and combed compact systems at count Ne 80 and 100’s carded yarns with 4.3 twist multiplier. The results indicated that yarns manufactured by the combed ring spinning frame are characterized by higher hairiness mean values in all studied cotton genotypes compared to those resulted of combed compact frame. Positive and highly significant association was observed between yarn hairiness and short fiber content while the associations between yarn hairiness and the rest fiber properties (fiber length (UHM), fiber strength (g/tex), micronaire, Elongation (%) and uniformity index (%)) were negative and significant or highly significant for all tested Egyptian cotton genotypes under the two spinning systems. The results of the full model regression and stepwise multiple linear regression differed according to the tested cotton genotype and also each of the applying spinning system and counts (Ne) carded used. Generally, all regression models were significant and explained large part of the variation of yarn hairiness expressed as high values of R2 and near values of the corresponding adjusted R2 indicating the validity and goodness of fit for these models.