Dyeing Defects

Dyeing And Printing 3(2+1)

Lesson 08 : Dyeing Defects

Dyeing Defects

Due to the faulty or improper dyeing procedures, or due to improper preparation of the fabric prior to dyeing, defects/imperfections can be noticed on the fabrics that are dyed.

  1. Barre: A horizontal band of off- shaded yarns extending from selvedge to selvedge. Usually found in knit fabrics, the problem is caused by a defect in the yarn, uneven tension in knitting, difference in tension of warp and weft yarns.

  2. Bleeding: loss of colour from a dyed fabric when immersed in a liquid or colour is discharged in to a liquid medium and transfer to another fabric.

    • A loss of dye of fabric or yarn up on wet treatment.
    • The colour runs when wet and will stain on contact.

  3. Crocking: The transfer of colour from one fabric to another by rubbing. A tendency of dye stuff to rub off a fabric, caused by improper dyeing methods or dye stuff, in sufficient dye penetration or insufficient washing and treating after dyeing operations.

  4. Fading: The loss of colour brilliance through exposure to factors such as sunlight or cleaning agents.

  5. Frosting: Colour changed in localized sections of a garment resulting from differential wear, such as collar points, knees at blue jeans etc.

  6. Fume fading: A change in shade or in actual colour of dyed fabrics caused by chemical reaction between certain acetate dyes with atmospheric contaminants such as burnt gas fumes and ozone.

  7. Fuzzy patterns: Design lines in printed fabrics that are meant to be sharp demarcations of colour but that are muted or blurred.

  8. Metamerism: A phenomenon that is observed when materials are viewed under different light sources. The spectral reflectance curves are not identical. The viewer sees one colour under one light source (incandescent) and a different colour under another light source ( fluorescent).

  9. Migration: The movement of the dye from one part of the fabric to another or movement within the fibre.

  10. Off shade: Irregular colouring of a fabric throughout the piece of goods. Sometimes this poor cast is Considered A Desirable Effect.

  11. Off register: Lacking colour alignment. In printing fabrics, the colour separation is imperfect, producing a situation in which the different colour components of the design are not aligned.

  12. Shade Bar: A shade change in the fabric which appears as a horizontal selvedge to selvedge change. Caused by a filling change (new filling bobbin) or loom stop and subsequent start up.

  13. Shading: Difference in the shade of the fabric from edge to edge or one end of the fabric to the other called selvage to selvage shading or end to end shading.

  14. Stained, Streaked: A discoloured area on the cloth caused by foreign matter such as direct, grease, oil or residues of sizing on the fabric being dyed.

  15. Tender spots: Weak areas in fabric resulting from chemical damage, which may be produced by improper bleaching, chemical spills, or improperly applied colorings or finishing agents.
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Last modified: Monday, 30 April 2012, 10:25 AM