Non-Bleaching Heather Method for Improved Whiteness of Greige Cotton

In accordance with the color space theory known as additive light mixing, the presence of dispersed blue-dyed fiber reduced the overall yellowness of a blended greige fiber and they were perceived as “whiter”. Various intimate blends of blue-dyed cotton fiber in greige cotton fiber were analyzed for color properties using a L*a*b* color space chromameter and a Ultraviolet-Visible (UV-Vis) spectrophotometer. A design of experiments (DOE) matrix approach provided a statistically-based mathematical means to predict the color properties of the intimate blends. The predictive accuracy of the mathematical model was confirmed in a follow-up experiment, and the blend resulting in the lowest yellowness and highest whiteness was determined. For fiber end uses which are too cost sensitive to support comprehensive wet chemical treatment of all of the fiber, such as nonwovens, intimate blending with low amounts of dyed fiber could produce visible effects at lower cost.