Contents
Chapter 1 Reactive Inkjet Printing—An Introduction 1
Patrick J. Smith and Aoife Morrin
1.1 Introduction 1
1.2 Reactive Inkjet Printing—The Concept 3
1.3 Types of Inkjet Printer 4
1.3.1 Continuous Inkjet Printing 5
1.3.2 Drop-on-demand Inkjet Printing 5
1.4 Droplet Formation 6
1.5 Printability and Z Number 9
References 10
Chapter 2 From Inkjet Printed Droplets to Patterned Surfaces 12
Jonathan Stringer
2.1 Introduction 12
2.1.1 Dimensionless Numbers 13
2.1.2 The Lifetime of a Deposited Droplet 13
2.2 Droplet Spreading on a Surface 15
2.2.1 Impact-driven Spreading 15
2.2.2 Surface Energy-driven Spreading 19
2.3 Phase Change 23
2.3.1 Evaporation 23
2.4 Interaction of Multiple Droplets 27
2.4.1 Coalescence 27
2.4.2 Bead Formation 29
2.5 Summary 33
References 34
Chapter 3 Droplet Mixing 38
Mark C. T. Wilson, J. Rafael Castrejón-Pita and
Alfonso A. Castrejón-Pita
3.1 Introduction 38
3.1.1 Mechanisms of Mixing 39
3.2 Diffusion and Advection 39
3.2.1 Pure Diffusion in a Sessile Droplet 40
3.2.2 Advection and Diffusion in a
Cavity Flow 42
3.2.3 Droplets as Micro-reactors 46
3.3 Mixing in Impacting and Coalescing
Droplets 46
3.3.1 Impact and Coalescence 47
3.3.2 Coalescence of Two Sessile
Droplets 52
3.4 Reactions Within Coalescing Droplets 53
3.5 Conclusions 55
Acknowledgements 56
References 56
Chapter 4 Unwanted Reactions of Polymers During the
Inkjet Printing
Process 59
Joseph S. R. Wheeler and Stephen G. Yeates
4.1 Introduction 59
4.2 Polymer Definitions 60
4.3 Polymer Molecular Weights 61
4.4 Polymer Solutions 63
4.5 Polymer Solutions in Flow Conditions 66
4.6 Inkjet Formulation Rules 70
4.7 The Maximum Concentration of Polymers
Printable by Inkjet Methods 71
4.8 Degradation of Linear Polymers During
DOD Printing 74
4.9 Degradation of Linear Polymers During
CIJ Printing 76
4.10 The Effect of Polymer Branching on Polymer
Degradation During Inkjet Printing 78
4.11 Mechanistic Insight of Polymer Degradation
During Inkjet Printing 81
4.12 Degradation of Polymers with Tertiary
Structure During Drop on Demand
Printing 82
4.13 Conclusions 83
References 84
Chapter 5 Reactive Inkjet Printing for Silicon Solar Cell
Fabrication 88
A. J. Lennon
5.1 Introduction 88
5.1.1 Crystalline Silicon Photovoltaics 88
5.1.2 Challenge of Patterning Dielectrics 89
5.1.3 Inkjet Printing in Silicon Photovoltaics 91
5.2 Patterning Using Polymer Masks 92
5.2.1 Novolac Resin Patterning by Dissolution 93
5.2.2 Resin Plasticising for Repeated
Patterning Steps 96
5.2.3 Inkjet Lithography 97
5.3 Direct Etching of Inorganic Dielectrics 102
5.4 Direct Metallisation 104
5.4.1 Metallisation through a SiNx
Antireflection Coating 105
5.4.2 Direct Metallisation of Silicon
Heterojunction Cells 108
5.5 Concluding Remarks 110
References 111
Chapter 6 Reactive Inkjet Printing: From Oxidation of
Conducting Polymers to Quantum Dots Synthesis 117
Ghassan Jabbour, Hyung Woo Choi, Mutalifu
Abulikamu, Yuka Yoshioka, Basma El Zein and
Hanna Haverinen
6.1 Introduction to Reactive Inkjet Printing 117
6.2 Grey Scale Sheet Resistivity via RIJ 118
6.3 Transitioning to Tool Friendly Oxidizing Agent 122
6.4 Reaction Mechanism and Characterization of
Oxidation Process 125
6.4.1 Sodium Hypochlorite Case 125
6.4.2 Hydrogen Peroxide Case 128
6.5 RIJ Printing: From Surface Modification to
Nanomaterials and Quantum Dots Assembly 129
6.6 Self-assembled Au NPs 130
6.7 Single Ink Approach to Au NPs Self-assembly 134
6.8 Increasing NPs Coverage and Reducing the
Self-assembly Time to 1 Minute 135
6.9 Au : Ag Nanoparticle Alloys via RIJ 135
6.10 RIJ Growth of ZnO Nanostructures 137
6.11 RIJ Printing of Quantum Dots 140
6.12 Conclusion 141
References 141
Chapter 7 Reactive Inkjet Printing of Silk Barrier Membranes
for Dental Applications 147
P. M. Rider, I. M. Brook, P. J. Smith and C. A. Miller
7.1 Introduction 147
7.1.1 Guided Bone Regeneration 147
7.1.2 Dental Barrier Membrane Materials 148
7.1.3 Silk 149
7.2 Materials and Methods 150
7.2.1 RSF Synthesis 150
7.2.2 nHA Synthesis 151
7.2.3 Film Production 152
7.2.4 Degradation 152
7.2.5 Infrared Spectroscopy 153
7.2.6 Cell Viability 153
7.2.7 Statistical Analysis 154
7.3 Removal of Sericin 154
7.4 Results and Discussion 155
7.4.1 Controlling β-sheet Formation 155
7.4.2 Degradation 158
7.4.3 Cell Viability 164
7.5 Conclusion 166
Acknowledgements 167
References 167
Chapter 8 Reactive Inkjet Printing of Regenerated Silk
Fibroin as a 3D Scaffold for Autonomous
Swimming Devices (Micro-rockets) 169
David A. Gregory, Yu Zhang, Stephen J. Ebbens and
Xiubo Zhao
8.1 Introduction 169
8.1.1 What Are Micromotors/Autonomous
‘Swimming’ Devices 170
8.1.2 Current Issues Concerning the Uses of
Micro-motors 175
8.1.3 Immobilization of Enzymes 176
8.1.4 Why Use Silk as a Bio-ink? 177
8.1.5 Advanced Fabrication of Micro-motors 178
8.2 Production of Silk-based Enzyme-powered
Micro-rockets 181
8.2.1 Preparation of Silk Ink Solution 181
8.2.2 Inkjet Printing Process of Silk Micro-rockets 182
8.2.3 Optimisation of Silk Micro-rockets and
Printing Process 184
8.2.4 The Silk Rocket Barrier Layer 186
8.3 Characterisation of Micro-motors 187
8.3.1 How Does Layer Thickness Affect
Average Column Height 188
8.3.2 Final Structures 188
8.4 Analysing the Trajectory Behaviour of
Symmetrical and Janus Silk Micro-rockets 192
8.4.1 Directionality Analysis – Alignment of
Particle to its Direction of Motion 193
8.5 Biocompatibility of Enzyme-powered Micromotors—
Ability to Swim in Biological Solutions 195
8.6 Lifetime of Enzyme Incorporated in Silk
Structure Versus Free Enzyme 196
8.7 Conclusions 197
References 198
Chapter 9 Reactive Inkjet Printing for Additive Manufacturing 202
Yinfeng He, Aleksandra Foerster, Belen Begines, Fan
Zhang, Ricky Wildman, Richard Hague, Phill Dickens
and Christopher Tuck
9.1 Introduction 202
9.1.1 Photo-polymerisation in AM 203
9.1.2 Photo-polymerisation 203
9.1.3 Ink 207
9.1.4 Applications 210
9.2 Heat-assisted Reactive Ink Jetting 211
9.2.1 Nylon 6 (Polyamide) 211
9.2.2 Polyimide 213
9.3 High Viscosity Ink Deposition 214
9.3.1 Introduction 214
9.3.2 Influence of Viscosity 215
9.3.3 High Viscosity Printing Methods 216
9.3.4 Droplet Mixing 217
9.4 Summary 218
References 218
Chapter 10 Reactive Inkjet Printing of Metals 222
Paul Calvert
10.1 The Need for Printed Metals 222
10.1.1 Conventional Technologies 222
10.1.2 Non-contact Printing 223
10.1.3 Reactive Inkjet Printing 224
10.2 Printing Technologies for Reactive ijp 224
10.3 Reactive Inks 225
10.3.1 Jetting 225
10.3.2 Reaction Stoichiometry 225
10.3.3 Kinetics of Deposition and Reaction 226
10.4 Other Deposition Chemistries 227
10.5 Substrates 228
10.5.1 Porous Substrates 228
10.5.2 Porous Substrates for RIJP of Metals 229
10.5.3 Modeling of Inks on Substrates 230
10.5.4 Other Substrates 231
10.6 Properties of Printed Patterns 232
10.6.1 Electrical Properties 232
10.6.2 Mechanical Properties 232
10.7 Comparison Between Different Metals 233
10.8 Comparison with Nanoparticle Printed Metals 234
10.9 Future Prospects 235
10.9.1 Industrial Inkjet Processes 235
10.9.2 Other Chemistries and Processes 235
10.9.3 Outstanding Problems 236
References 236
Chapter 11 The Use of Reactive Inkjet Printing in Tissue
Engineering 240
Christopher Tse, Yi Zhang and Patrick J. Smith
11.1 Introduction 240
11.2 Tissue Engineering 240
11.3 Alginate-based Systems 242
11.4 Fibrin-based Systems 249
11.5 Gelatin-based Systems 250
11.6 Optimal Printing Conditions of Glutaraldehyde
Printing 252
11.7 Inkjet Printing Glutaraldehyde to Cross-link
Gelatin 253
11.8 Cell Seeding onto Inkjet-printedglutaraldehyde-
cross-linked-gelatin 253
11.9 Conclusions 260
References 261
Subject Index 263