Monolithic Inkjet Printhead for Matched Multi-Color Droplet Ejection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing piezoelectric inkjet printheads face challenges with complex manufacturing, reduced reliability due to numerous electrical connections, and complications in multi-color printing, particularly in achieving uniform ink droplet ejection and precise actuation for different ink compositions.
Innovation Solution
A monolithic inkjet printhead design with integrated ejectors for multiple ink compositions, utilizing piezoelectric actuators coupled to nozzles for inertial ejection, ensuring consistent droplet volume and velocity through matched physical properties and resonant frequencies, reducing wiring complexity and enabling high-quality printing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If multiple piezoelectric actuators are used for multi-color printing, then printing capability is improved, but wiring complexity and device complexity increase
Solution Approach 1:
The patent combines multiple piezoelectric actuators and their control circuits onto a single substrate, integrating what would traditionally be separate components requiring multiple external connections into one unified device. This merging eliminates the need for complex external wiring while maintaining multi-color printing capability through multiple integrated actuators.
Solution Approach 2:
The substrate serves multiple functions simultaneously: it acts as the structural base for the piezoelectric actuators, provides the control circuitry for driving multiple nozzles, and enables multi-color printing capability. This multi-functional integration reduces the need for separate components and connections.
2Manufacturing precision
If many parallel electrical connections are used to drive individual piezoelectric actuators, then print resolution is improved, but reliability decreases
Solution Approach 1:
By integrating the control circuits directly onto the substrate with the piezoelectric actuators, the patent reduces the number of external electrical connections required. Fewer connections mean fewer potential failure points, thereby improving reliability while maintaining the ability to drive multiple actuators for high-resolution printing.
3Manufacturing precision
If different actuation waveforms are used for different ink compositions, then ejection precision is improved, but operation complexity increases
Solution Approach 1:
The integrated control circuits on the substrate can dynamically adjust actuation parameters such as voltage amplitude and pulse width for each piezoelectric actuator. This allows different ink compositions to be ejected with optimized waveforms while maintaining a unified control architecture, preventing operation complexity from increasing despite the need for precise control of multiple parameters.
4Device complexity
If a monolithic design with integrated ejectors is used, then device complexity is reduced, but manufacturing precision requirements increase
Solution Approach 1:
The patent employs local quality by providing individual control circuits for each piezoelectric actuator on the substrate. This allows precise, localized adjustment of actuation parameters for each nozzle, compensating for manufacturing variations and ensuring uniform droplet ejection across all nozzles despite the integrated design.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The printhead achieves precise and reliable ejection of different ink compositions with uniform droplet size and shape, minimizing manufacturing complexity and acoustic cross-talk, while allowing for a compact and efficient printing apparatus.
Implementation Method 1
Deformation of a piezoelectric element causes deflection of the piezoelectric actuator, inducing a pressure change in the ink stored within the chamber and thereby causing ink droplet ejection through a nozzle
Implementation Method 2
ensuring consistent droplet volume and velocity through matched physical properties and resonant frequencies
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present disclosure provides a monolithic inkjet printhead for ejecting a set of ink compositions, wherein the printhead comprises at least one substrate and the substrate comprises a plurality of ejectors each comprising: (i) a nozzle, (ii) a chamber for receiving an ink composition of the set, wherein said chamber is in fluid communication with said nozzle, and (iii) a piezoelectric actuator coupled to said nozzle for selectively ejecting said ink composition therefrom, wherein each ejector is configured to eject ink droplets of the different ink compositions with corresponding volume and velocity. The disclosure further provides a set of ink compositions per se with matched values of viscosity, density and surface tension, a printing apparatus, and methods thereof.