Design of Piezo Inkjet Print Heads

An integral overview of the theory and design of printheads, authored by an expert with over 30 years’ experience in the field of inkjet printing.

Clearly structured, the book presents the design of a printhead in a comprehensive and clear form, right from the start. To begin with, the working principle of piezo-driven drop-on-demand printheads in theory is discussed, building on the theory of mechanical vibrations and acoustics. Then the design of single-nozzle as well as multi-nozzle printheads is presented, including the importance of various parameters that need to be optimized, such as viscosity, surface tension and nozzle shape. Topics such as refilling the nozzle and the impact of the droplet on the surface are equally treated. The text concludes with a unique set of worked-out questions for training purposes as well as case studies and a look at what the future holds.

An essential reference for beginning as well as experienced researchers, from ink developers to mechanical engineers, both in industry and academia.

INTRODUCTION
 
SINGLE, TWO, THREE AND FIVE DEGREES OF FREEDOM
Effect of Nozzle Shape
Schematic of Fluidic and Acoustic System
Surface Tension, Viscosity and Compressibility, Frequency Dependent Damping
Piezo Theory
Rayleigh's Method
Pulse Shape Definition
Non-Linear Effects
Fluidic Cross-Talk
Examples
 
LONG WAVE GUIDE THEORY SINGLE & MULTI NOZZLE PRINT HEAD
Wave Speed
Governing Equations
Solution Strategies
Damping
Complex Pulse Shapes, Multi Pulsing
Examples
 
DROPLET FORMATION
Energy Consideration
Influence of Meniscus Position on Droplet Speed and Size
Influence of Droplet Formation on Dynamics of Fluid Motion
Cooling of Free Flying Droplet
Jetting of Viscoelastic Inks
Examples
 
REFILLING
Surface Tension Driven Refilling
Inertia Effects
Start-up Effects
Multi Pulsing & Gray Scaling
Examples
 
IMPACTING DROPLETS
Viscosity and Surface Tension Dominated Spreading
Inertia Dominated Spreading
Splashing
Examples
 
PERMEATION AND DRYING
Washburn Theory
Drying of Liquid Droplets
Examples
 
CONCLUSIONS AND OUTLOOK

• By (author) J. Frits Dijksman