A Quantitative Study of Differential Dyeing of Cotton as a Means of Elucidating Fiber Structure

Abstract

An analytical procedure is described for placing the differential dye test for cotton fiber maturity on a quantitative and objective basis. The procedure involves the ex traction of the two dyes from a differentially dyed sample and spectrophotometrically analyzing the red and green dye uptake. The G/R value, defined as the ratio of green and red dye uptake, is shown to be a sensitive index of cotton fiber maturity. The mechanism of the differential dye test is discussed in terms of dyeing rates and fiber structure. The effects of swelling treatments on the differential dyeing test are also discussed.