Costs of Reactive Dyeing of Cotton using Winch, Jet or Pad-Steam Equipment

A survey of the dyeing of knitted cotton fabric in the UK showed a complete absence of semi-continuous or continuous dyeing, unlike the situation for woven fabric, and for knitted fabrics in some other countries. Most dyehouses used batch processing in winch or jet equipment and justified this choice on the grounds of expediency since the equipment was readily available. The first section of this paper describes calculations undertaken to compare jet dyeing with pad-steam continuous dyeing. Representative machinery was selected and typical cotton fabric was used in this comparison. The second section of this paper describes practical work carried out to compare the winch processes used in different dyehouses when dyeing cotton cloth with reactive dyes. Costs of chemicals, steam, water and effluent charges are compared and show wide variations. A representative dye Remazol Black B (HOE) (C.I. Reactive Black 5) and a typical cotton-interlock fabric were used in this work