Copper Conductive Paste Imidazole-Silane Copolymer Coating
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Copper-based conductive pastes face challenges with oxidation and heat stability, leading to reduced conductivity and limited application due to surface oxidation of copper powders, which is not adequately addressed by existing surface treatment methods.
Innovation Solution
A copper-based conductive paste is developed using a partially cross-linked imidazole-silane copolymer to form an anti-corrosive coating on copper powders, which are then mixed with a binder and solvent, eliminating the need for heat treatment and providing corrosion and heat resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If copper powder is used as conductive filler, then cost is reduced compared to silver, but oxidation resistance deteriorates leading to rapid conductivity loss
Solution Approach 1:
The patent applies composite materials by combining copper powder with a silane-based protective coating layer. The copper core provides high conductivity and cost advantage, while the silane coating layer provides oxidation resistance. This composite structure resolves the contradiction between cost reduction and oxidation resistance maintenance.
Solution Approach 2:
The silane-based protective coating acts as an intermediary between the copper powder and the oxidizing environment. This coating layer prevents direct contact between oxygen and the copper surface, thereby maintaining oxidation resistance while allowing the copper to retain its cost advantage compared to silver.
2Reliability
If copper powder surface is treated with organic polymer compound, then oxidation resistance is improved, but heat stability deteriorates due to oxide film formation at 150°C or above
Solution Approach 1:
The patent changes the chemical parameters of the protective coating by using silane-based compounds with specific functional groups that provide both oxidation resistance and thermal stability. The silane coating undergoes hydrolysis and condensation reactions to form a stable cross-linked structure that maintains integrity at high temperatures, resolving the heat stability issue while preserving oxidation protection.
Solution Approach 2:
Instead of using expensive silver coating or complex multi-layer protective systems, the patent employs a simple silane-based coating that provides adequate protection. The coating is designed to be thin and lightweight, offering sufficient oxidation and heat resistance without compromising the underlying copper's properties.
3Reliability
If conventional surface treatment methods are used, then oxidation resistance is partially improved, but conductivity and application range remain limited
Solution Approach 1:
The silane-based protective coating provides multiple functions simultaneously: oxidation resistance, heat stability, and maintained conductivity. This multi-functional coating enables the copper-based conductive paste to be applied in various fields including printed electronics, solar cells, and electromagnetic shielding, significantly expanding the application range beyond what conventional treatments achieve.
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 resulting copper-based conductive paste exhibits excellent corrosion resistance and heat stability, enabling cost-effective mass production with improved conductivity and expanded application possibilities without requiring high-temperature curing processes.
Implementation Method 1
treating a surface of a copper powder with partially cross-linked imidazole-silane copolymer in order to prevent oxidation of the copper powder
Implementation Method 2
partially cross-linked imidazole-silane copolymer
Data Source
AI summary
The present inventive concept relates to a copper based conductive paste and its preparation method. The copper based conductive paste comprises a copolymer-copper composite comprising an imidazole-silane copolymer with partially cross-linked structure and a copper powder, a solvent, a binder and an additive. The imidazole-silane copolymer with partially cross-linked structure is introduced into the copper powder whose surface is treated by a hydrochloric acid aqueous solution and a phosphoric acid aqueous solution. The imidazole-silane copolymer is polymerized by using an imidazole monomer represented by following formula 1, a silane monomer represented by following formula 2 and a cross-linking agent.In Formula 1, X represents a hydrogen atom (H) or a methyl group (—CH3), and R1 represents a vinyl group or an allyl group.In Formula 2, Y represents a methoxy group, a 2-methoxy ethoxy group or an acetoxy group, and R2 represents a vinyl group.