List of Contributors XV Preface XXI 1 Introductory Remarks 1 Ian M. Hutchings, Graham D. Martin, and Stephen D. Hoath 1.1 Introduction 1 1.2 Drop Formation: Continuous Inkjet and Drop-on-Demand 2 1.3 Surface Tension and Viscosity 6 1.4 Dimensionless Groups in Inkjet Printing 8 1.

5 Length and Time Scales in Inkjet Printing 9 1.6 The Structure of This Book 11 1.7 Symbols Used 11 References 12 2 Fluid Mechanics for Inkjet Printing 13 Edward P. Furlani 2.1 Introduction 13 2.2 Fluid Mechanics 13 2.3 Dimensions and Units 14 2.4 Fluid Properties 15 2.

4.1 Density 15 2.4.2 Viscosity 16 2.4.2.1 Newtonian Fluids 17 2.4.

2.2 Non-Newtonian Fluids 17 2.4.3 Surface Tension 18 2.5 Force, Pressure, Velocity 19 2.6 Fluid Dynamics 20 2.6.1 Equations of Fluid Dynamics 20 2.

6.1.1 Conservation of Mass 21 2.6.1.2 Conservation of Momentum 21 2.6.1.

3 Conservation of Energy 22 2.6.2 Solving the Equations of Fluid Dynamics 24 2.7 Computational Fluid Dynamics 25 2.7.1 Preprocessor 26 2.7.2 Solver 28 2.

7.3 Postprocessor 28 2.8 Inkjet Systems 29 2.8.1 Inkjet Modeling Challenges 31 2.8.1.1 Free-Surface Analysis 32 2.

8.1.2 Fluid-Structure Interaction 35 2.8.1.3 Phase Change Analysis 35 2.8.1.

4 Ink-Media Interaction 35 2.8.1.5 Non-Newtonian Fluids 35 2.8.2 Inkjet Processes 36 2.8.2.

1 DOD Droplet Generation 36 2.8.2.2 CIJ Droplet Generation 43 2.8.2.3 Crosstalk 45 2.8.

2.4 Aerodynamic Effects 47 2.8.2.5 Ink-Media Interactions 48 Summary 52 Acknowledgments 53 References 53 3 Inkjet Printheads 57 Naoki Morita, Amol A. Khalate, Arend M. van Buul, and Herman Wijshoff 3.1 Thermal versus Piezoelectric Inkjet Printing 57 3.

2 Thermal Inkjet 58 3.2.1 Boiling Mechanism 58 3.2.1.1 Theoretical Model 58 3.2.1.

2 Observation of Boiling Bubble Behavior 59 3.2.2 Printhead Structure 63 3.2.3 Jetting Characteristics of TIJs 64 3.2.3.1 Input Power Characteristics and Heat Control of TIJs 64 3.

2.3.2 Frequency Response and Crosstalk Control 65 3.2.4 Problems Associated with Pressure and Heat Generated in TIJs 66 3.2.4.1 Cavitation Damage on the Heater Surface 66 3.

2.4.2 Ink Residue Scorching (Kogation) on the Heater Surface 67 3.2.5 Evaporation ofWater in Aqueous Ink 69 3.2.5.1 Approaches to Compensate for Condensed Ink through Evaporation 69 3.

2.5.2 Measurement of Physical Properties of Flying Droplets 70 3.3 Future Prospects for Inkjets 72 3.3.1 Printing Speed Limit Estimated by Drop Behavior 72 3.3.2 Control of Bleeding Caused by High-Speed Drying 72 3.

4 Continuous Inkjet (CIJ) 74 3.5 Examples and Problems (TIJ) 76 3.5.1 Example 76 3.5.2 Problem 76 3.6 Piezo Inkjet Printhead 78 3.6.

1 Introduction 78 3.6.2 Working Principle 79 3.6.3 Ink Channel Behavior 82 3.6.3.1 Residual Oscillations 82 3.

6.4 Control of Inkjet Printhead 84 3.6.4.1 Constrained Actuation Pulse Design 84 3.6.4.2 Complex Actuation Pulse Design: Feedforward Control Approach 86 3.

6.5 Industrial Applications 88 References 89 4 Drop Formation in Inkjet Printing 93 Theo Driessen and Roger Jeurissen 4.1 Introduction 93 4.1.1 Continuous Inkjet Printing 93 4.1.2 Drop-on-Demand Inkjet Printing 94 4.2 Drop Formation in Continuous Inkjet Printing 95 4.

2.1 Rayleigh-Plateau Instability 96 4.2.2 Satellite Formation 99 4.2.3 Final Droplet Velocity 99 4.2.3.

1 Capillary Deceleration 99 4.2.3.2 Acceleration due to Advection 101 4.3 Analysis of Droplet Formation in Drop-on-Demand Inkjet Printing 102 4.3.1 The Scenario of the Analyzed Droplet Formation 102 4.3.

1.1 Head Droplet Formation 103 4.3.1.2 Tail Formation 105 4.3.1.3 Pinch-Off and Tail Breakup 108 4.

4 Worked Examples 111 4.4.1 Tail Formation for the Purely Inertial Case 111 4.4.2 Dispersion Relation of the Rayleigh-Plateau Instability 112 Acknowledgment 114 References 114 5 Polymers in Inkjet Printing 117 Joseph S.R. Wheeler and Stephen G. Yeates 5.

1 Introduction 117 5.2 Polymer Definition 117 5.3 Source- and Architecture-Based Polymer Classification 118 5.4 Molecular Weight and Size 118 5.5 Polymer Solutions 122 5.6 Effect of Structure and Physical Form on Inkjet Formulation Properties 124 5.7 Zimm Interpretation for Polymers in High Shear Environments 125 5.8 Printability of Polymer-Containing Inkjet Fluids 126 5.

9 Simulation of the Inkjet Printing of High-Molecular-Weight Polymers 129 5.10 MolecularWeight Stability of Polymers during DOD Inkjet Printing 130 5.11 MolecularWeight Stability of Polymers during CIJ Printing 132 5.12 MolecularWeight Stability of Associating Polymers During DOD Inkjet Printing 134 5.13 Case Studies of Polymers in Inkjet Formulation 135 5.13.1 Role of Polymer Architecture 135 5.13.

2 Inkjet Printing of PEDOT:PSS 136 5.13.3 Inkjet Printing of Polymer-Graphene and CNT Composites 136 References 137 6 Colloid Particles in Ink Formulations 141 Mohmed A. Mulla, Huai Nyin Yow, Huagui Zhang, Olivier J. Cayre, and Simon Biggs 6.1 Introduction 141 6.1.1 Colloids 141 6.

1.2 Inkjet (Complex) Fluids 141 6.2 Dyes versus Pigment Inks 142 6.3 Stability of Colloids 143 6.3.1 DLVOTheory 144 6.3.2 van derWaals Attractive Force 144 6.

3.3 Electrostatic Repulsive Force 145 6.3.4 Stabilization of Colloidal Systems 146 6.4 Particle-Polymer Interactions 149 6.4.1 Steric Stabilization 149 6.4.

2 Bridging Flocculation 150 6.4.3 Depletion Flocculation 151 6.5 Effect of Other Ink Components on Colloidal Interactions 152 6.5.1 Surfactants 152 6.5.2 Viscosity Modifiers 153 6.

5.3 Humectants 153 6.5.4 Glycol Ethers 154 6.5.5 Storage - Buffers and Biocides 154 6.5.6 Other Additives 155 6.

6 Characterization of Colloidal Dispersions 155 6.6.1 Dynamic Light Scattering (DLS) 155 6.6.2 Electrophoretic Mobility (Zeta Potential) 156 6.6.3 Rheology 157 6.6.

4 Bulk Colloidal Dispersion 157 6.6.5 Jetting 159 6.7 Sedimentation/Settling 160 6.7.1 Sedimentation Characterization Techniques 162 6.8 Conclusions/Outlook 165 References 166 7 Jetting Simulations 169 Neil F. Morrison, Claire McIlroy, and Oliver G.

Harlen 7.1 Introduction 169 7.2 Key Considerations for Modelling 172 7.3 One-Dimensional Modelling 177 7.3.1 The Long-Wavelength Approximation 177 7.3.2 A Simple CIJ Model 178 7.

3.3 Error Analysis for Simple Jetting 180 7.3.4 Validation of the Model by Rayleigh''s Theory 180 7.3.5 Exploring the Parameter Space 183 7.3.6 A Numerical Experiment 184 7.

4 Axisymmetric Modelling 185 7.4.1 Continuous Inkjet 186 7.4.2 Drop-on-Demand 189 7.5 Three-Dimensional Simulation 194 References 196 8 Drops on Substrates 199 Sungjune Jung, Hyung Ju Hwang, and Seok Hyun Hong 8.1 Introduction 199 8.2 Experimental Observation of Newtonian Drop Impact onWettable Surface 201 8.

2.1 Effect of Initial Speed on Drop Impact and Spreading 202 8.2.2 Effect of SurfaceWettability on Drop Impact and Spreading 206 8.2.3 Effect of Fluid Properties on Drop Impact and Spreading 208 8.3 Dimensional Analysis: The Buckingham PiTheorem 209 8.4 Drop Impact Dynamics: The Maximum Spreading Diameter 211 8.

4.1 Viscous Dissipation Dominates Surface Tension 213 8.4.2 The Flattened-Pancake Model 214 8.4.3 The Kinetic Energy Transfers Completely into Surface Energy 215 8.4.3.

1 Evaporation: A Scaling Exponent of the Radius 216 References 218 9 Coalescence and Line Formation 219 Wen-Kai Hsiao and Eleanor S. Betton 9.1 Implication of Drop Coalescence on Printed Image Formation 219 9.2 Implication of Drop Coalescence on Functional and 3D Printing 220 9.3 Coalescence of Inkjet-Printed Drops 222 9.3.1 Coalescence of a Pair of Liquid Drops on Surface 222 9.3.

2 Coalescence with Drop Impact 226 9.3.3 Coalescence of a Pair of Inkjet-Printed Drops 229 9.3.3.1 Experimental Setup 230 9.3.3.

2 Necking Stage Dynamics 230 9.3.3.3 Discussion 234 9.3.3.4 Summary 234 9.4 2D Features and Line Printing 235 9.

4.1 Model of Drop-Bead Coalescence 236 9.4.2 Experiment and Observations 237 9.4.2.1 Effect of Drop Spacing 238 9.4.

2.2 Effect of Drop Deposition Interval 242 9.4.3 Stability Regimes and Discussion 244 9.4.4 Summary 246 9.5 Summary and Concluding Remarks 247 9.6 Working Questions 248 References 249 10 Droplets Drying on Surfaces 251 Emma Talbot, Colin Bain, Raf De Dier, Wouter Sempels, and Jan Vermant 10.

1 Overview 251 10.2 Evaporation of Single Solvents 252 10.3 Evaporation of Mixed Solvents 259 10.3.1 Marangoni Flows 260 10.3.1.1 Thermal Marangoni Flows 260 10.

3.1.2 Solutal Marangoni Flows 262 10.4 Particle Transport in Drying Droplets 263 10.4.1 The "Coffee Ring Effect" 263 10.4.1.

1 Disadvantages to the Ring-Shaped Pa.