Silver Nanoparticle Ink Composition for Stable Conductive Films
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing metallic fine particle inks fail to provide sufficient storage stability and exhibit high volume resistivity fluctuations due to temperature changes, limiting their application in printed electronics.
Innovation Solution
The ink contains metallic fine particles with a volume average particle diameter of 20-50 nm and a specific ratio of particle diameter to crystallite size of 1.6-3.1, regulated through controlled reduction and freeze-drying processes, enhancing dispersion stability and reducing volume resistivity fluctuations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If metallic fine particles are used in conventional inks, then conductivity is achieved, but storage stability deteriorates and volume resistivity fluctuates with temperature changes
Solution Approach 1:
The patent applies parameter changes by precisely controlling the volume average particle diameter (20-50 nm) and the ratio of particle diameter to crystallite size (1.6-3.1). These specific parameter ranges optimize both storage stability and volume resistivity characteristics, resolving the contradiction between reliability and harmful fluctuations.
Solution Approach 2:
The patent uses composite material approach by combining metallic fine particles with specific organic compounds (carboxylic acid, phenol, or amine groups) as dispersants. This composite system enhances storage stability while controlling volume resistivity fluctuations through the synergistic interaction between the metal particles and organic dispersant molecules.
2Stability of the object's composition
If metallic fine particles with smaller particle diameter are used, then dispersion stability improves, but manufacturing complexity increases due to precise particle size control requirements
Solution Approach 1:
The patent defines specific parameter ranges (volume average particle diameter: 20-50 nm, DA/LA ratio: 1.6-3.1) that balance dispersion stability with manufacturability. These parameter specifications provide clear manufacturing targets while ensuring optimal performance, avoiding both excessive particle size and unreasonable precision requirements.
Solution Approach 2:
The patent employs preliminary action by pre-forming metallic fine particles with controlled size and crystallite structure before ink formulation. The particles are prepared with specific crystallite orientations and size distributions in advance, then incorporated into the ink system with appropriate dispersants, simplifying the overall manufacturing process.
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 solution provides a metallic fine particle-containing ink with improved storage stability and low volume resistivity, enabling stable jetting and forming reliable metal films in printed electronics.
Implementation Method 1
Metallic fine particles can form a metal film having conductivity through sintering
Implementation Method 2
a step of freeze-drying a reduced product obtained in the step 1
Data Source
AI summary
A metallic fine particle-containing ink, including a metal constituting the metallic fine particles comprising silver, the metallic fine particles contained in the ink having a volume average particle diameter DA of 20 nm or more and 50 nm or less, and the metallic fine particles contained in the ink having a ratio (DA/LA) of the volume average particle diameter DA with respect to a crystallite size LA (nm) obtained from a (111) plane in powder X-ray diffractometry of the metallic fine particles of 1.7 or more and 2.5 or less.