Introduction
Processes | Water requirements in L/1,000 kg of products |
---|---|
Desizing | 2,500–21,000 |
Scouring | 20,000–45,000 |
Bleaching | 2,500–25,000 |
Dyeing | 10,000–300,000 |
Printing | 8,000–16,000 |
Materials and methods
Materials
Experimental methods
Conventional methods
Desizing process
Scouring process
Bleaching process
Direct dyeing of cotton fabric
Modified method
Testing and analysis
Testing of desized fabric
Principle
Preparation of the iodine solution
Application of the iodine solution
Testing of scoured fabric
Testing of bleached fabric
Colour depth (in terms of K/S value and colour strength) and colour difference (in terms of L, a and b values)
Washing fastness evaluation
Light fastness evaluation
Rubbing fastness evaluation
Results and discussions
Dyes/Samples | dE
|
K/S
| Relative strength (%) |
L
|
a
|
b
|
C
|
h
| |
---|---|---|---|---|---|---|---|---|---|
Red 5B | A | – | 5.44 | 100 | 49.277 | 46.568 | 9.557 | 47.539 | 11.593 |
B | 0.70 | 8.57 | 157.46 | 49.686 | 46.473 | 10.128 | 47.564 | 12.289 | |
C | 0.65 | 9.60 | 176.41 | 49.327 | 45.996 | 9.88 | 47.045 | 12.118 | |
D | 0.63 | 7.00 | 128.67 | 49.505 | 47.036 | 9.921 | 48.071 | 11.906 | |
E | 1.2 | 6.51 | 119.60 | 49.253 | 45.648 | 8.787 | 46.486 | 10.891 | |
Blue GLL | A | – | 5.35 | 100 | 41.243 | −1.584 | −23.681 | 23.734 | 266.139 |
B | 1.43 | 6.50 | 121.38 | 41.871 | −2.859 | −23.844 | 24.015 | 263.129 | |
C | 0.78 | 6.38 | 119.10 | 41.606 | −2.274 | −23.738 | 23.847 | 264.494 | |
D | 0.62 | 5.29 | 98.79 | 41.452 | −2.156 | −23.529 | 23.628 | 264.73 | |
E | 1.33 | 6.14 | 114.67 | 41.868 | −2.032 | −24.772 | 24.855 | 265.276 | |
Yellow 5GLL | A | – | 7.04 | 100 | 79.484 | 1.974 | 69.327 | 69.355 | 88.333 |
B | 2.67 | 9.00 | 127.73 | 78.317 | 1.14 | 67.074 | 67.084 | 88.99 | |
C | 3.61 | 8.82 | 125.27 | 77.734 | 1.398 | 66.214 | 66.229 | 88.755 | |
D | 2.61 | 7.11 | 100.86 | 78.261 | 3.458 | 67.549 | 67.637 | 87.034 | |
E | 1.93 | 6.87 | 97.56 | 80.533 | 0.657 | 70.272 | 70.275 | 89.428 | |
Black FR | A | – | 11.13 | 100 | 25.719 | −1.222 | −3.242 | 3.465 | 249.319 |
B | 0.32 | 14.08 | 126.44 | 25.584 | −1.138 | −2.962 | 3.173 | 248.955 | |
C | 0.29 | 14.74 | 132.44 | 25.554 | −1.091 | −3.04 | 3.23 | 250.23 | |
D | 0.04 | 11.40 | 102.44 | 25.698 | −1.256 | −3.256 | 3.49 | 248.878 | |
E | 0.41 | 11.71 | 105.21 | 25.934 | −1.554 | −3.136 | 3.5 | 243.614 | |
Olive Green BL | A | – | 6.00 | 100 | 56.367 | −7.205 | 30.301 | 31.146 | 103.406 |
B | 4.81 | 8.00 | 133.34 | 54.763 | −10.358 | 27.032 | 28.949 | 110.993 | |
C | 3.67 | 7.69 | 128.23 | 55.069 | −9.492 | 27.739 | 29.318 | 108.919 | |
D | 2.59 | 5.72 | 95.31 | 54.225 | −6.397 | 31.53 | 32.172 | 101.5 | |
E | 1.50 | 5.52 | 92.11 | 55.62 | −6.141 | 29.537 | 30.169 | 101.776 | |
Turquoise Blue BRLE | A | – | 7.22 | 100 | 56.316 | −29.568 | −28.716 | 41.217 | 224.145 |
B | 3.75 | 8.04 | 111.35 | 55.412 | −30.528 | −25.196 | 39.583 | 219.518 | |
C | 3.23 | 8.02 | 111.06 | 55.197 | −30.158 | −25.744 | 39.652 | 220.469 | |
D | 1.45 | 6.26 | 86.67 | 55.368 | −29.189 | −27.676 | 40.224 | 223.458 | |
E | 2.33 | 6.06 | 83.96 | 55.464 | −29.778 | −26.55 | 39.895 | 221.703 |
Colour strength measurement of dyed samples
Colour fastness properties of dyed samples
Dyes/samples | Fastness properties | ||||||
---|---|---|---|---|---|---|---|
Washing | Light | Rubbing | |||||
CC | SC | SW | Dry | Wet | |||
Red 5B | A | 4 | 1–2 | 3 | 2 | 4–5 | 4 |
B | 3–4 | 1–2 | 2 | 2 | 4–5 | 4 | |
C | 3–4 | 1–2 | 2 | 2 | 4–5 | 4 | |
D | 4 | 1–2 | 3 | 2 | 4–5 | 4 | |
E | 4 | 1–2 | 2 | 2 | 4–5 | 4 | |
Blue GLL | A | 4–5 | 3–4 | 3 | 4 | 4–5 | 4 |
B | 4–5 | 3 | 3 | 3 | 4–5 | 4 | |
C | 4–5 | 3 | 3 | 4 | 4–5 | 4 | |
D | 4–5 | 3–4 | 3 | 4 | 4–5 | 4 | |
E | 4–5 | 3–4 | 3–4 | 3 | 4–5 | 4 | |
Yellow 5GLL | A | 4–5 | 3–4 | 3 | 4 | 4–5 | 4–5 |
B | 4–5 | 2–3 | 2 | 4 | 4–5 | 4–5 | |
C | 4–5 | 2–3 | 2 | 5 | 4–5 | 4–5 | |
D | 3–4 | 2–3 | 3 | 4 | 4–5 | 4–5 | |
E | 4 | 3–4 | 3 | 5 | 4–5 | 4–5 | |
Black FR | A | 4–5 | 4 | 3–4 | 3 | 4–5 | 4–5 |
B | 4–5 | 3–4 | 3 | 2 | 4–5 | 4–5 | |
C | 4 | 3–4 | 3 | 3 | 4–5 | 4–5 | |
D | 4 | 3–4 | 3–4 | 3 | 4–5 | 4–5 | |
E | 4 | 3 | 3–4 | 3 | 4–5 | 4–5 | |
Olive green BL | A | 4 | 3 | 3 | 3 | 4–5 | 4–5 |
B | 4 | 2–3 | 3 | 2 | 4–5 | 4–5 | |
C | 4 | 2–3 | 3 | 2 | 4–5 | 4–5 | |
D | 4 | 2–3 | 3 | 2 | 4–5 | 4–5 | |
E | 4 | 3 | 3 | 3 | 4–5 | 4–5 | |
Turq. blue BRLE | A | 4 | 3–4 | 3–4 | 5 | 4–5 | 4 |
B | 4 | 3 | 3–4 | 5 | 4–5 | 4 | |
C | 4 | 3 | 3–4 | 5 | 4–5 | 4 | |
D | 4 | 3–4 | 3–4 | 5 | 4–5 | 4 | |
E | 4 | 3 | 4 | 5 | 4–5 | 4 |
Absorbency of dyed fabric samples
Samples | Absorbency (s) |
---|---|
Undyed RFD fabric | <3 |
Dyed control (RFD) sample | <3 |
Undyed grey fabric | >600 |
Dyed grey fabric | 15–20 |
Dyed desized fabric | 10–15 |
Dyed scoured fabric | <3 |
One bath pre-treatment and dyed fabric | 10–12 |
Comparison of conventional and combined process
Steps in the processes | Water consumption (L) | Energy consumption (kcal) | Time consumption (min) |
---|---|---|---|
Desizing (MLR 1:30) | 30 | 900.4 | 120 |
Cold wash (MLR 1:50) | 50 | 0.0 | 5 |
Hot wash (MLR 1:50) | 50 | 3,501.7 | 10 |
Neutralisation (MLR 1:50) | 50 | 0.0 | 10 |
Scouring (MLR 1:30) | 30 | 2,101.0 | 120 |
Cold wash (MLR 1:50) | 50 | 0.0 | 5 |
Hot wash (MLR 1:50) | 50 | 3,501.7 | 10 |
Bleaching (MLR 1:30) | 30 | 1,500.7 | 60 |
Cold wash (MLR 1:50) | 50 | 0.0 | 5 |
Hot wash (MLR 1:50) | 50 | 3,501.7 | 10 |
Neutralisation (MLR 1:50) | 50 | 0.0 | 10 |
Dyeing (MLR 1:20) | 19 | 1,330.6 | 60 |
Dye fixing treatment (MLR 1:20) | 20 | 600.3 | 30 |
Cold wash (MLR 1:50) | 50 | 0.0 | 5 |
Total | 529 | 16,938 | 460 |
Steps in the processes | Water consumption (L) | Energy consumption (kcal) | Time consumption (min) |
---|---|---|---|
Combined pre-treatment and dyeing (MLR 1:20) | 19 | 1,330.6 | 60 |
Dye fixing treatment (MLR 1:20) | 20 | 600.3 | 5 |
Cold wash (MLR 1:50) | 50 | 0.0 | 30 |
Total | 89 | 1,930.9 | 95 |