Washed Cotton—Manufacture, Properties, and Processing Part I: Experimental Program1

Abstract

Investigations dealing with the washing of cotton of sample sizes ranging from 1 to 10,000 pounds (.45 to 4,536 kg) have been carried out. Processes have included both batch-washing of loose fiber and continuous washing of fiber in lap form. The optimum technique has been shown to be that of continuously washing cotton in lap form with 66°C water on rayon staple fiber manufacturing equipment. Results of the washing experiments have shown that approximately the same amount of material is removed by washing at water temperatures of 60 to 100°C. Fiber washed in this way has shown reduced respirable dust levels in carding and reduced gram-negative bacteria and endotoxin levels. Carding of this cotton in a model card room also elicited lower worker FEV1 (forced expiratory volume in one second) reaction than unwashed cotton. This cotton was converted into 100% cotton and 50/50 cotton/polyester ring and open-end yarns and fabrics at normal production speeds.