| 摘要 |
Two-tone or multicolour dyeings on woollen materials in loose yarn or fabric form are obtained by treating them in a boiling solution comprising a metal salt having mordanting properties, a reducing agent and an acid giving a pH of 2-6, combining the woollen materials so treated with untreated woollen materials and dyeing with mordant acid or other wool dyes or a combination thereof. The mordanting metals may be Cr, Cn, Co, Mn, Fe or Ac, the preferred salt being potassium or sodium dichromate. The reducing agent may be sodium bisulphite, thiosulphate or hydrosulphite or potassium bitartrate. After rinsing and drying, the treated wool is combined by carding, combing, spinning, twisting, weaving, knitting, tufting or assembling with the untreated wool materials. Additionally woollen materials pre-dyed in dark shades may also be combined with the said composite. The final dyeing step may be accomplished in the usual manner from a bath at a pH of 4-5.5 containing Glauber's salt and a condensate of stearyl diethylene triamine and ethylene oxide as well as other known auxiliaries, e.g. condensates of:- naphthalene sulphonic acid and formaldehyde, naphthalene sulphonic acid, formaldehyde and dihydroxydiphenylsulphone, 3, 4-dichlorophenylisocyanate and 4, 41-dichlor-2-amino-diphenylether-21-sulphonic acid as well as ethoxylated nonyl phenols. Suitable mordant dyes for this process are well known as are the acid (including 1:1 and 1:2-metal complex and reactive type) dyes which may be co-employed. Sometimes a mordant may be applied with the dyestuff so as to "top-chrome" the dye on the unmordanted material. Examples are given particularly of two-tone dyeing tufted carpets. |
