departement technologie Fashionable Destruction, Responsable? Jeans, a voyage from the cotton plant to the wardrobe and beyond departement technologie Denim Value chain – people (S)/planet (E)/profit (P) S: ++ S: -/- E direct: + S: -/- S: -/- S: -/- S: + E: -/- E indirect: ? E: -/- E: + E: -/- E: + P: -/- P: + P: +/- P: +/- P: +/- P: +/- Garment Design Agricul- Textile Garment manufac- Retail ture mill finishing Marketing turing 2 departement technologie Material: Cotton Cotton picking in 1890 Cotton covers 2,5 % of the cultivated land but uses 16 % of the world’s pesticides/insecticides 3 departement technologie Fabric: yarn • Past: 100 % ring spun cotton yarn • Today: ring spun yarn replaced by open end yarn Neps in rotor yarn tend to be spun into the solid yarn body  less structured fabric 4 departement technologie Fabric: weave • Yarn is processed into a twill fabric (2/1 or 3/1) 5 departement technologie Colour • Warp is dyed with (natural) indigo (http://www.youtube.com/watch?v=hXeectd1GSM) Extraction of natural indigo 6 departement technologie Indigo dyeing process • Rope dyeing or beam dyeing – continuous process – Yarn is ring-dyed • Indigo is not soluble in water – Solubilize by adding sodium hydrosulfite, thiourea dioxide or a commercial reducing agent in alkaline conditions, pH 9-11 (NaOH) (reduction): yellow-greenish solution (vat) 7 departement technologie Special effects • Yarn • Weaving • Dyeing process • Coating • Washing • Brushing, 3D-effects, spraying, laser, sandblasting, … 8 departement technologie 9 departement technologie Yarn • Use multitwist or multicount yarn in the warp – Multitwist: speeding up of the spinning  machine over a certain distance thicker and thinner areas in the yarn – Multicount: giving more or less feed to the spinning machine • Crossedge effect by using multitwist or multicount in warp and weft 10