PROBLEM 
NO.

PROBLEM DESCRIPTION  

CAUSES

  A

Unlevelness (due to dyeing conditions)  

  1.

Ending problems

1. Unstable dye dispersion

2. Unsuitable dye combination

3. Wrong dyeing program

  2.

Cloudy dyeing

1. Inadequate pretreatment

2. Channeling due to irregular winding

3. Wrong loading of the machine or bobbins (too much material, too tight winding, etc.)

4. Poor circulation of the goods due to interruptions, knots, etc.

5. Too much foam in the dye bath

6. Wrong dyeing programme (heating, pressure, speed)

  3.

Pale areas

1. Inadequate pretreatment

2. Air pockets in the material (e.g. cheeses)

  B

Unlevelness (due to material)  

  4.

Barriness

1. Variations in temperature during fibre manufacture (texturizing), draft differences

2. Variations in the density of the material (weaving, knitting)

  C

Unlevelness (due to other reasons)  

  5.

Skitterness

1. Inadequate pretreatment (e.g. desizing)

2. Fibres of different origins in the material

3. Inadequate penetration (paler points of intersection)

4. Poorer solidity on both components of fibre blends

5. Irregular thread tension during weaving or warp knitting

  6.

Listing

1. Inconsistent setting temperature

2. Irregular tension in the material due to weaving or warp knitting

3. Poorly wound material

4. Rolled in selvedges due to irregular tension in the material (weaving, warp, knitting)

  7.

Pale areas after dyeing

1. Effect of aggressive vapours (e.g. acid, chlorite, formaldehyde)

  D

Reproducibility  

  8.

Deviation of shade

1. Dye sensitivity to hydrolysis, reduction, electrolyte

2. Dye sensitivity to metal ions in the dye bath

3. Dyes of different chemical constitution affect each other (rare)

4. Dye build up affected by chemicals (retarding affect)

5. Different dyeing programmes

6. Different liquor ratios

7. Dye shows differences in standard conformity

8. Unsuitable dye combination

9. Sedimentation of liquid dyes

10. Bath exhaustion affected by reserve of adjacent fibre

  9.

Dyeing too pale

1. Different build up of dye on different materials

10.

Precipitates in the dye bath

1. Chemicals affect each other’s action

2. Dyeing produced at too low temperature

3. Dyeing time too short

4. Unstable chemicals

11.

Change of shade

1. Unfinished diffusion due to insufficient dyeing time at too low temperature

2. Inadequate sublimation fasteners of dye

  E

Fastneess properties  

12.

Unexpectedly poor light fastness

1. Carrier residues on fabric (inadequate thermo fixation)

2. Stained adjacent fibre

3. Catalytic fading due to unsuitable dye combination

13.

Unexpectedly poor wet and rub fastness

1. Thermo migration due to finishing and softening chemicals

2. Inadequate dye fixation due to too short dyeing time or too low fixation temperature

3. Stained adjacent fibre

  F

Spots, marks 

14.

Precipitates in the dye bath

1. Dye precipitates due to poor dispersion or dyes with poor dispersion stability

2. Dye crystallization due to variations in temperature in the dye bath

3. Coloured spots due to dye deposits on the machine

4. Use for volatile carriers

5. Silicones in the dye bath

6. Unstable chemicals

7. Oil and spinning preparations

8. Oligomers in the dye bath

15.

Singeing droplets

1. As a result of singeing before dyeing, fibre tips exhibit higher affinity for dyes

16.

Change of shade (e.g. blue spots in brilliant red shades)

1. Dye is sensitive to metal ions

2. Alkali residues

3. Finishing chemicals

17.

Dark spots

1. Solvent residues from pretreatment

18.

Specks

1. Contamination of the material by dyestuff dust

19.

Dirt spots

1. Contamination of the material by rust, oil, graphite, etc.

  G

Appearance of the goods

20.

Dimensional stability (shrinkage)

1. Insufficient relaxation during pretreatment

2. Inadequate setting of material

3. Lengthwise distortion caused by dyeing machine

21.

Creasing

1. Inadequate pretreatment (scouring, relaxation, setting)

2. Due to quality of goods (structure, e.g. tightly woven fabric, weight)

3. Poor suitability of dyeing machine

4. Too heavy batch of fabric

5. Incorrect loading of machine

6. Dyeing process (heating, cooling)

22.

Chafe marks

1. Mechanical friction due to overloading

2. Rough patches in the machine

3. Stationary material in the running machine (knots)

4. Too high machine speed

23.

Stitch distortion (knits)

1. Inadequate pretreatment (relaxation, setting)

2. Mechanical effects, e.g. passage of goods in machine, squint seams

24.

Moire effects (on beam)

1. Inadequate pretreatment (setting, rolling up)

25.

Luster

1. Physical change in fibre due to local pressure and high temperature on material

2. Excessive setting

26.

Handle

1. Unfavorable conditions between machine and material

2. Inadequate pretreatment (relaxation, setting)

3. Wrong dyeing programme (temperature/time)

27.

Pilling (staple fibres)

1. Susceptible fibre origin (also in fibre blends)

2. Inconsistent dimensional stability due to shrinkage (fibres protrude from fibre bundle)

Other problems  

28.

Difficulty with heavy shades on fine denier yarn

1. Fibre surface

29.

Soiling of machine

30.

Frosting on goods

31.

Poor running of material in subsequent processing

1. Oligomers

Thermo sol dyeing problems

32.

Listing

1. One-sided liquor feed into the through

2. Different nip roller pressure

3. Unlevel migration in intermediate drying

4. Uneven thermosolling or fixation of dyes due to temperature differences

33.

Two-sidedness

1. Deflecting roller touched on one side only

2. Deflecting roller stationary

3. Pad rollers not the same

4. Uneven drying from side to side

34.

Dark or pale selvedges

1. One-sided liquor feed into the through

2. Narrow goods impregnated on a wide padder

3. Worn rollers, rollers bend due to over compensation

4. Varying drying conditions over the width of the goods

5. Alkali residues in the goods

35.

Barry dyeing

1. Uneven jet pressure in the drier

2. Inadequate evenness of tension in drier, crease formation

3. Alkali residues in the goods

36.

Spots, specks

1. Pale marks due to condensation drops

2. Foam spots due to excessive foaming of the pad liquor

3. Coloured specks due to incorrect preparation of the pad liquor

4. Alkali residues in the goods

37.

Ending

1. Dye substantivity

2. Dye sedimentation

38.

Pale points of intersection

1. Poor penetration

2. Severe migration

39.

Foam formation

1. Dispersants in the dye

2. Residues of boiling off agent

40.

Frosting

1. Migration during thermosolling

2. Fibre tips not dyed (e.g. viscose)