Cotton quality - fibre to fabric: fibre properties relationships to fabric quality

Cotton quality - fibre to fabric: fibre properties relationships to fabric quality

[Abstract]: The textile industry has a recurrent white speck nep problem in cotton. “White specks” are immature clusters of fibres that are not visible as defects until dyeing, after which they remain white on the surface of a darkly dyed fabric, or appear as non uniform streaks in the fabric. Both results render the fabric unsuitable for commercial fashion fabrics. The white speck potential of cotton is difficult to predict except in extremely immature cottons. Competitive synthetic fibres are uniform in length and strength and never have a maturity problem resulting in dye defects. They are much more predictable in the mill. As a result, cotton faces the risk of being replaced by synthetic fibres. Industry requires a method to predict fabric quality from cotton bale fibre properties to minimize this risk.

This research addresses the problem of predicting white specks in dyed cotton fabrics. It is part of a large study, which is supported jointly by US and Australian agencies. The main objective is to predict fabric quality from bale fibre properties given controlled gin and mill processing. Gin and mill processing must be controlled so that field and varietal effects can be seen without the interaction of mechanical processing differences. This results in achieving other objectives, including the provision of baseline data for Australian varieties, ginning effects and comparison of ring and open-end spinning.

Initially a reliable method for measuring white specks had to be found. Several systems have been evaluated and are reported here. The systems accuracy was compared using fabrics from the US Extreme Variety Study (EVS), which was grown specifically to have different levels of white specks. The fabrics made from the US (Leading Variety Study 1993 (LVS) and The American Textile Manufacturers Institute (ATMI) Cotton Variety Processing Trials, 2001) and the Australian (1998 & 1999) variety studies were analysed using AutoRate-2-03, the best of the image analysis systems studied. The final release of AutoRate (February 2003) was developed by Dr. Bugao Xu to measure white specks on dark fabrics in conjunction with this research. This final analysis of these studies results in white speck prediction equations from high-speed fibre measurement systems. This information should be immediately useful to as a tool to measure the effects of field and ginning practices on the levels of white specks without having to carry the research out to finished fabrics. Cotton breeders will be able to use the equations in the development of new varieties with low white speck potential, by eliminating varieties with high white speck potential early on. The research will continue on a much larger scale in the US and hopefully a WSP (White Speck Potential) value will be incorporated into the US Cotton Grading System.