Physico-chemical Aspects of Textile Coloration

The production of textile materials comprises a very large and complex global industry that utilises a diverse range of fibre types and creates a variety of textile products. As the great majority of such products are coloured, predominantly using aqueous dyeing processes, the coloration of textiles is a large-scale global business in which complex procedures are used to apply different types of dye to the various types of textile material. The development of such dyeing processes is the result of substantial research activity, undertaken over many decades, into the physico-chemical aspects of dye adsorption and the establishment of 'dyeing theory', which seeks to describe the mechanism by which dyes interact with textile fibres.

Physico-Chemical Aspects of Textile Coloration provides a comprehensive treatment of the physical chemistry involved in the dyeing of the major types of natural, man-made and synthetic fibres with the principal types of dye. The book covers:

• fundamental aspects of the physical and chemical structure of both fibres and dyes, together with the structure and properties of water, in relation to dyeing;

• dyeing as an area of study as well as the terminology employed in dyeing technology and science;

• contemporary views of intermolecular forces and the nature of the interactions that can occur between dyes and fibres at a molecular level;

• fundamental principles involved in dyeing theory, as represented by the thermodynamics and kinetics of dye sorption;

• detailed accounts of the mechanism of dyeing that applies to cotton (and other cellulosic fibres), polyester, polyamide, wool, polyacrylonitrile and silk fibres;

• non-aqueous dyeing, as represented by the use of air, organic solvents and supercritical CO2 fluid as alternatives to water as application medium.

The up-to-date text is supported by a large number of tables, figures and illustrations as well as footnotes and widespread use of references to published work. The book is essential reading for students, teachers, researchers and professionals involved in textile coloration.

Autorentext

Professor Stephen Burkinshaw is a Professor of Textile Chemistry at the University of Leeds. His research interests include the chemistry and application of dyes and pigments to natural and man-made fibres, colour measurement and textile finishing. He is the author of ~200 publications including a textbook on dyeing theory (Chemical Principles of Synthetic Fibre Dyeing, Springer, 1995.) and section editor for the Springer publication, Encyclopedia of Colour Science and Technology, which is due for publication in 2013.
As both a tutor of part-time students sitting ASDC Paper C: Properties of Materials and Finished Products and Fundamental Mechanisms of Industrial Processes and examiner of ASDC Paper C (1994-1999), as well as the person responsible for teaching and examining all three undergraduate years in Dyeing Theory within the Department of Colour Science at Leeds University, Professor Burkinshaw has first-hand, tangible experience of how students view and use this particular book.

Inhalt
Society of Dyers and Colourists xi Preface xiii

1 Fundamental Aspects of Textile Fibres 1

1.1 Textiles 1

1.1.1 Yarn 2

1.1.2 Fabric 4

1.1.3 Textile Markets 6

1.2 Textile Fibres 6

1.2.1 Textile Fibre Classification 7

1.2.2 Textile Usage 9

1.2.3 The History and Development of Textile Fibres 9

1.2.4 Textile Polymers 12

1.2.5 Textile Fibre Morphology and Fine Structure 16

1.3 General Physical and Mechanical Characteristics of Textile Fibres 27

1.3.1 Length 27

1.3.2 Fineness 27

1.3.3 Twist 32

1.3.4 Fibre Specific Surface Area, Sm or Sv 33

1.3.5 Cross-Sectional Shape 33

1.4 Properties of Textile Fibres 35

1.4.1 Mechanical Properties 35

1.4.2 Thermal Properties 37

1.4.3 Optical Properties 48

References 51

2 Dyes 65

Introduction 65

2.1 Dyes 65

2.1.1 Historical Aspects 66

2.1.2 Classification of Colorants 71

2.1.3 Colour and Constitution 75

2.1.4 Commercial Dye Forms 75

2.1.5 Commercial Dye Names 76

2.1.6 Global Dye Consumption 76

References 76

3 The Role of Water in Aqueous Dyeing 81

Introduction 81

3.1 Water Structure 82

3.2 Water Availability and Global Consumption 84

3.2.1 Water Footprint 85

3.3 Water Use in Dyeing 86

3.3.1 Water Used in Cotton Production 86

3.3.2 Water Used in Fibre Processing 87

3.3.3 Water Used in Dyeing 87

3.4 Water and Textile Fibres 91

3.4.1 Hydrophilicity and Hydrophobicity 93

3.4.2 Moisture Sorption 94

3.4.3 The Porous Nature of Fibres 103

3.4.4 Wetting and Wicking 105

3.4.5 Swelling 109

3.4.6 Water Plasticisation 110

3.5 Water and Dyes 116

3.5.1 Solvation 117

3.5.2 Dye Solubility 120

3.5.3 Dye Aggregation in Solution 123

3.5.4 Dye Aggregation in the Fibre 129

3.5.5 Aqueous Dye Dispersions 129

3.6 pH and pK 134

3.6.1 Water Ionisation (Ionic Product of Water) 134

3.6.2 The pH Scale 135

3.6.3 pKa and pKb 136

3.6.4 Buffer Systems and the HendersonHasselbalch Equation 136

References 137

4 Fundamentals of Dyeing 153

Introduction 153

4.1 DyeFibre Systems 154

4.2 Fundamental Principles of Dyeing 156

4.2.1 DyeFibre Substantivity 156

4.2.2 Driving Force for Dyeing 157

4.2.3 Dye Exhaustion 157

4.2.4 Rate of Dyeing 158

4.2.5 Depth of Shade 159

4.2.6 Liquor Ratio 159

4.2.7 Dye Fixation 160

4.2.8 Wash-Off 161

4.2.9 Fastness 162

4.2.10 Dyeing Auxiliaries 163

References 164

5 DyeFibre Interactions 167

Introduction 167

5.1 Intermolecular Interactions (or Forces) between Atoms and Molecules 167

5.1.1 Covalent Bonds 169

5.1.2 IonIon Interactions (aka ChargeCharge, Coulomb, Electrostatic Interactions) 169

5.1.3 IonDipole Interactions (aka ChargeDipole, MonopoleDipole) 169

5.1.4 Van der Waals Interactions (aka van der Waals Forces) 170

5.1.5 Hydrogen Bonds 172

5.1.6 Hydrophobic Effect and Hydrophobic Interactions 172

5.1.7 Total (Attractive and Repulsive) Intermolecular Potentials 173

5.1.8 Aromatic Interactions (aka -Interactions, -Effects) 173

5.2 Intermolecular Interactions (or Forces) between Macromolecules and Surfaces 176

5.2.1 Dispersion Interactions 176

5.2.2 Electrostatic Forces 178

5.3 Intermolecular Forces in the Context of Textile Fibres and Dyes 190

5.3.1 Intermolecular Forces in Textile Polymers 190

5.3.2 Intermolecular Forces between Dyes and Fibres 191 ...