Cotton Dyeing in Glycol Solvents1

Abstract

Cotton fabrics were dyed in glycol and glycol-ether solvents with suitable cotton dyes such as direct and sulfur dyes. Good dye-uptake was obtained only when the cotton was prewet with water before dyeing. Enhanced color saturation occurred if the fabric was pretreated with a 0.25 to 2 molar solu tion of potassium thiocyanate or other suitable salt. Glycols, such as ethylene glycol, diethylene glycol, and higher molecular weight glycols in the series, were poor solvents for dyeing cotton, but propylene glycol, dipropylene glycol, and glycol ethers were suitable. Propylene glycol was effective for crossdyeing cotton/polyester and cotton/wool blends at temperatures of 150°C and higher for as little as 2.5 minutes in some cases. The most effective solvents for maximum color saturation were the glycol ethers, especially ethylene glycol monomethyl ether.