Textile Dyeing
By Dr. N. N. Mahapatra
Contents
Preface xiii
1 Introduction 1
1.1 Dye types 1
1.2 Dyeing process 2
1.3 Dyes 3
1.3.1 Synthetic dyes 3
1.3.2 Basic/cationic dyes 4
1.3.3 Direct dyes 4
1.3.4 Chrome dyes 4
1.3.5 Vat dyes 4
1.3.6 Reactive dyes 4
1.3.7 Disperse dyes 5
1.3.8 Sulphur dyes 5
1.3.9 Pigment dyes 5
1.4 Dyeing methods 5
1.4.1 Loose stock dyeing 5
1.4.2 Top dyeing 6
1.4.3 Piece dyeing 6
1.4.4 Beck dyeing 6
1.4.5 Jigger dyeing 6
1.4.6 Pad dyeing 6
1.4.7 Jet dyeing 6
1.4.8 Solution pigmenting or dope dyeing 7
1.4.9 Garment dyeing 7
1.4.10 Yarn dyeing 7
1.4.11 Bale dyeing 8
1.4.12 Batik dyeing 8
1.4.13 Beam dyeing 8
1.4.14 Burl or speck dyeing 8
1.4.15 Chain dyeing 8
1.4.16 Cross dyeing 9
1.4.17 Jig dyeing 9
1.4.18 Piece dyeing 9
1.4.19 Random dyeing 9
2 Fibre dyeing 11
2.1 Loose stock dyeing 11
2.1.1 Definition of stock dyeing 11
2.1.2 Dyeing of loose acrylic fibres 12
2.1.3 Dyeing procedure 13
2.1.4 Cotton fibre dyeing 14
2.1.5 Dyeing of fire retardant textile in loose staple fibre dyeing 15
2.1.6 Exhaust dyeing of viscose loose fibre 15
2.1.7 Polyester loose fibre dyeing 17
2.2 Top dyeing 18
2.2.1 Top dyeing process 20
2.2.2 Worsted spinning 21
2.2.3 Synthetic spinning 21
2.3 Gel dyeing 22
2.3.1 Production of gel-dyed acrylic fibres 23
2.3.2 Uses 24
2.3.3 Advantages of gel dyeing 24
2.3.4 Gel dyeing 26
2.3.5 Application of gel dyeing in fibre 26
2.3.6 Properities of gel dyeing 26
2.3.7 Preparing acrylamide gels 27
2.3.8 Composition 27
2.3.9 Mechanism of gel dyeing 29
2.4 Tow dyeing 30
2.4.1 Dyes used in acrylic tow dyeing 30
2.4.2 Advantages of dyed acrylic tow 32
2.4.3 Conclusion 33
2.5 Dope dyeing 33
2.5.1 Process 33
2.5.2 Merits and demerits 34
2.5.3 Package-dyed yarns 34
2.5.4 Dope-dyed yarns 35
2.5.5 Viscose dope dyeing 36
2.5.6 Polyester dope dyeing 38
2.5.7 Polypropylene dope dyeing 38
2.5.8 Nylon dope dyeing 39
2.5.9 Acrylic dope dyeing 39
2.6 Flock dyeing 39
2.6.1 What is flocking? 40
2.6.2 Application methods 41
2.6.3 The flock 42
2.6.4 The adhesive 43
2.6.5 The electrostatic system 43
2.6.6 Hand held units 44
2.6.7 The environment 44
2.6.8 Uses of flock fibres 45
3 Yarn dyeing 47
3.1 Package dyeing 47
3.1.1 Working process of package dyeing machine 48
3.1.2 Advantages of package dyeing machine 49
3.1.3 Types of package dyeing machines 50
3.1.4 Liquor flow 51
3.1.5 Open expansion tank 52
3.2 Hank dyeing 52
3.2.1 Manual method 52
3.2.2 Why hank dyeing? 53
3.2.3 Product quality 53
3.2.4 Economy of process 53
3.2.5 Types of different hank dyeing machines 54
3.2.6 Dyeing of cotton in hank form 58
3.2.7 Dyeing of wool in hank form 58
3.2.8 Dyeing of viscose in hank form 58
3.2.9 Dyeing of acrylic hanks 58
3.2.10 Polyester hank dyeing 59
3.3 Space dyeing 60
3.3.1 Hank or skein printing 60
3.3.2 Space dyeing in package form 60
3.3.3 Knit–deknit process 61
3.3.4 Continuous or warp yarn printing 62
4 Resist dyeing 65
4.1 Mechanical resist 66
4.2 Chemical resist 67
5 Fabric dyeing 71
5.1 Jigger dyeing 72
5.1.1 Advantages of jigger dyeing machine 72
5.1.2 Disadvantages of jigger dyeing machine 73
5.1.3 Objective of jigger dyeing machine 73
5.1.4 Dyeing process 73
5.1.5 Cotton jigger dyeing 75
5.2 Winch dyeing (beck dyeing) 76
5.2.1 Features and parameters 76
5.2.2 Description and dyeing method on winch dyeing machine 78
5.2.3 Advantages of winch dyeing machine 79
5.2.4 Limitations of winch dyeing machine 79
5.3 Jet dyeing 79
5.3.1 Advantages of jet dyeing machine 80
5.3.2 Disadvantages jet dyeing machine 80
5.3.3 Features of jet dyeing machine 80
5.3.4 Types of jet dyeing machine 81
5.3.5 Overflow jet dyeing machine 81
5.3.6 Airflow dyeing machine 84
5.4 Soft flow dyeing 86
5.4.1 Key features of soft flow dyeing machine 87
5.4.2 Principle of soft flow dyeing machine 87
5.4.3 Types of soft flow dyeing machine 87
5.4.4 Soft flow dyeing machine 88
6 Denim dyeing 101
6.1 Rope dyeing 101
6.1.1 Pre-scouring 103
6.1.2 Hot wash 103
6.1.3 Cold wash 103
6.1.4 Dye bath 103
6.1.5 Washing 105
6.1.6 Why softener 106
6.1.7 Importance of high concentration of free hydrosulphite 106
6.1.8 Indigo dyeing process control 106
6.1.9 Guidelines 106
6.1.10 Dipping time 107
6.1.11 Squeeze pressure 107
6.1.12 Airing time 107
6.1.13 Drying 107
6.1.14 Effect of pH 107
6.2 Sheet dyeing 107
6.2.1 Slasher/sheet dyeing 108
6.2.2 Process sequence in indigo slasher/sheet dyeing 109
6.2.3 Advantages of slasher/sheet dyeing 111
6.2.4 Disadvantages 111
6.3 Rope dyeing and sheet dyeing 111
7 Continuous dyeing 113
7.1 Pad-batch method 116
7.1.1 Pad (alkali)-batch (cold) process 116
7.1.2 Pad (alkali)-batch (hot) process 121
7.1.3 Pad-dry method 121
7.1.4 Pad-steam method 122
7.1.5 Factors involved in the dyeing process 122
7.1.6 Special features of pad-batch dyeing process 124
7.1.7 Special features and applications 125
7.1.8 Thermosol dyeing method 125
7.1.9 Paper heat transfer dyeing method 126
7.2 Pad-dry-pad steam process 127
7.3 Pad steam process 128
7.3.1 Pad-steam dyeing machine/process 129
7.3.2 Purposes of the machine 130
7.3.3 Process that can be done on this machine 130
7.3.4 Main sections of the machine 130
7.3.5 Pad-pad-steam process 132
7.3.6 Pad-air/steam process 132
7.3.7 Pad-dry-thermofix process 134
7.4 Pad-thermosol-pad steam process 135
7.5 E-control: a new process for dyeing 137
7.5.1 The basic principle of the E-control process 139
7.5.2 The key variables 139
7.5.3 Features of the E-control process 140
7.5.4 Product quality 141
7.5.5 Process 143
7.5.6 Performance 143
7.5.7 Benefits 144
7.5.8 E-control technology 147
7.5.9 Thermex E-control T-CA 152
8 Garment dyeing 153
8.1 Garment dyeing machineries 153
8.2 Paddle dyeing machines 154
8.3 Rotary drum dyeing machines 155
8.3.1 Tumbler dyeing machines 156
8.3.2 Toroid dyeing machines 157
8.3.3 The gyrobox 157
8.3.4 MCS readymade garment dyeing machine 158
8.3.5 Modified Pegg Toroid Whiteley garment
dyeing machines 158
8.3.6 Advantages of garment dyeing 158
8.3.7 Disadvantages of garment dyeing 158
8.4 Dip dyeing 159
8.4.1 Application of dip dyeing machine 160
8.4.2 Process flowchart for dip dyeing 161
8.4.3 Pre-treatment 161
8.4.4 Enzyme 162
8.4.5 After treatment 163
Index 165