Resin Composition for Inductors with Low Thixotropy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional resin compositions exhibit high thixotropy, which impairs their filling properties when used in applications such as filling holes or forming magnetic layers, leading to inferior performance in inductor elements.
Innovation Solution
A resin composition comprising an alloy magnetic powder with a specific BET surface area range, a magnetic powder with another specific BET surface area range, and a binder resin, optimized in volume and mass ratios to achieve low thixotropy and high relative magnetic permeability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the filling rate of magnetic powder is increased to improve magnetic properties, then relative permeability is improved, but thixotropy increases and filling property deteriorates
Solution Approach 1:
The patent applies parameter changes by controlling the BET specific surface area of the magnetic powder within a specific range (0.5 to 5.0 m²/g) and optimizing the composition ratios of different magnetic powder components. This allows achieving high filling rates with moderate thixotropy, resolving the contradiction between magnetic properties and filling property
Solution Approach 2:
The patent uses a composite magnetic powder system consisting of multiple types of magnetic powders with different properties (different BET specific surface areas and compositions). This composite approach enables optimizing both the magnetic performance and the rheological properties for good filling behavior
2Reliability
If the content of magnetic powder is increased to enhance magnetic properties, then relative permeability is improved, but thixotropy increases and processing becomes difficult
Solution Approach 1:
The patent changes the critical parameter of BET specific surface area to a controlled range (0.5 to 5.0 m²/g) which prevents excessive thixotropy even at high magnetic powder contents. This parameter optimization enables processing high-filled compositions without severe viscosity increase
Solution Approach 2:
The patent utilizes magnetic powders with controlled porous structures that have moderate BET specific surface areas. The porous structure allows achieving high magnetic moment while controlling the surface area to volume ratio, thereby managing thixotropy at high filling rates
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 composition achieves excellent filling properties and high relative magnetic permeability, enhancing the performance of inductor elements by balancing thixotropy and magnetic properties.
Implementation Method 1
a resin composition including a magnetic powder... (A) an alloy magnetic powder... (B) a magnetic powder... giving a cured product having a high relative magnetic permeability
Implementation Method 2
the thixotropy of the resin composition tends to increase as the filling rate of the magnetic powder is increased
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
A resin composition comprising: (A) an alloy magnetic powder having a BET specific surface area SA of 2 m2/g or more and 10 m2/g or less; (B) a magnetic powder having a BET specific surface area SB of 0.1 m2/g or more and less than 2 m2/g; and (C) a binder resin.