Submitted to: American Association of Textile Chemists and Colorists Review
Publication Type: Peer reviewed journal
Publication Acceptance Date: 6/9/2010
Publication Date: 7/1/2011
Citation: Bel, P., Xu, B., Yao, X. 2011. White speck potential for mechanically harvested cottons. American Association of Textile Chemists and Colorists Review. 11(4):59-65. Interpretive Summary: Spindle picked cotton brings in lower levels of immature fiber and foreign matter than stripper harvested cotton The combination of higher levels of gin cleaning, and immature fibers results in higher levels of white speck neps in fabrics from the stripper harvested cotton than the spindle harvested cotton. The common theme that runs through white specks is that the number of neps, fiber maturity and severity of processing influence white speck levels. A bale of cotton’s white speck potential can be determined by using the preliminary prediction equations presented in the paper. It is desirable to have tools that enable us to detect white specks by developing a WSP and educate our end users and market high WSP cottons for specific products to maximize their end product quality. Neps, as measured by AFIS, or the Buckling coefficient in HVI’s case, have the most influence on the level of white specks seen in the dyed fabrics and can be used to help mill avoid dye defects from immature fibers.More work needs to be done and should include hand picked cottons to address the international cotton industry’s concerns.
Technical Abstract: This paper examines the white speck phenomena as seen in mechanically picked cottons based on HVI, AFIS and white speck fabric data. White specks are dye defects that can be inherent from the variety or can be caused by weather or other field conditions, and the fabric manufacturer is often caught off guard by them. Research shows that mechanical processing from field to fabric affects white speck levels. In this paper, we will look specifically at impacts of harvest and spinning methods on white speck formation. The cottons were ginned for grade, so stripper harvested cottons would normally have more mechanical processing than the spindle picked cottons to remove excess trash. Once in the mill, the bale fiber was processed identically for this study. With the controlled mill processing, this research shows the effect that harvesting/ginning can cause in white speck levels. The stripper picked and spindle picked cottons were spun on the ring, open end and vortex systems, which also have different effects on the levels of white specks. Ultimately, we would like to develop strong predictions of white specks from the bale fiber data tested by high-speed instruments, and have the white speck potential (WSP) included in the classification of cottons. Bales with high WSP can be put into a special class for whites only, combed or use for vortex or rotor spinning (both processes remove white specks), maximizing the fiber's potential and minimizing mill losses due to white specks.