Flexible Overcoat Ink for Scratch-Resistant Printed Electronics
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current digitally printable conductive inks for printed electronics lack flexibility, scratch resistance, and adhesion, limiting their application in robust environments such as smart packaging that requires durability during shipping and handling.
Innovation Solution
A printable flexible overcoat ink composition is developed, comprising a mixture of thermoplastic polyurethane (TPU) and a solvent, with a viscosity range of 1 to 2,000 centipoise, allowing digital printing and providing strong adhesion and scratch resistance, formulated to include TPU with an average particle diameter of 10 to 200 nanometers and a solvent like water or ethylene glycol, ensuring stability and compatibility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If conventional digitally printable conductive inks are used, then digital printing is enabled, but flexibility and scratch resistance are poor
Solution Approach 1:
The patent changes the physical and chemical parameters of the ink formulation by incorporating TPU particles (1-100 micrometers) into the conductive ink, adjusting the viscosity to 1-2000 centipoise, and optimizing the ratio of conductive material to TPU binder to achieve both printability and mechanical durability
Solution Approach 2:
The patent creates a composite ink formulation combining conductive materials (such as metal particles or carbon) with TPU binder particles, where the TPU provides flexibility and scratch resistance while the conductive material maintains electrical conductivity, resulting in a composite material that satisfies multiple requirements simultaneously
2Strength
If flexible conductive inks are used, then flexibility is improved, but conductivity is insufficient
Solution Approach 1:
The patent optimizes the concentration and size distribution of TPU particles (1-100 micrometers) to balance flexibility and conductivity, ensuring the ink remains printable while achieving the desired mechanical properties without compromising electrical performance
Solution Approach 2:
The composite formulation uses TPU as a flexible binder matrix that holds conductive particles in continuous pathways, allowing the ink to bend and flex while maintaining electrical connectivity through the conductive particle network embedded within the flexible TPU structure
3Strength
If high viscosity ink is used, then scratch resistance improves, but digital printing becomes difficult
Solution Approach 1:
The patent carefully controls the viscosity parameter within the range of 1-2000 centipoise by adjusting TPU particle concentration and size, ensuring the ink is thick enough to provide scratch resistance upon drying but thin enough to flow properly through digital printing systems without clogging or requiring excessive pressure
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 ink composition provides a flexible, scratch-resistant overcoat layer with high adhesion to conductive traces, maintaining conductivity and integrity through multiple folding cycles and handling, while preventing printhead clogging and evaporation, suitable for both inkjet and aerosol jet printing.
Implementation Method 1
a printable flexible overcoat ink composition comprising a mixture of a thermoplastic polyurethane (TPU) and a solvent, wherein the mixture has a viscosity of 1 centipoise to 2,000 centipoise to allow the mixture to be digitally printed
Implementation Method 2
The printable flexible overcoat ink of the present disclosure provides compatibility and strong adhesion to the conductive traces of the printed electronics
Implementation Method 3
preventing printhead clogging and evaporation
Data Source
AI summary
A printable flexible overcoat ink composition that can be digitally printed is disclosed. For example, the printable flexible overcoat ink composition includes a mixture of a thermoplastic polyurethane (TPU) and a solvent. The mixture is mixed to have a viscosity of 1 centipoise to 2,000 centipoise to allow the mixture to be digitally printed via an inkjet printhead or an aerosol jet printhead.