Stretchable Conductive Film for EMI Shielding on Irregular Surfaces

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing electromagnetic wave shielding materials lack sufficient stretchability and conformability to irregular surfaces, leading to gaps and reduced conductivity when conforming to three-dimensional curved surfaces.

Innovation Solution

A conductive film comprising a thermosetting resin layer with specific mechanical properties and a conductive layer containing a metal complex, which provides high elongation, tensile modulus, and storage modulus, along with a controlled film thickness and resistivity, ensuring flexibility and conductivity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a conductive layer is formed on a stretchable base material, then the shielding material has stretchability, but the conductive layer is cracked when bent or conforming to sharp irregularities, deteriorating conductivity

Engineering Contradiction:

ImprovestretchabilityVSAvoidconductivity

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The patent changes the physical and chemical parameters of the conductive layer by using a metal complex formulation with specific solvents and additives that enable the layer to stretch without cracking. The conductive layer is designed with controlled film thickness (0.1-3.0 μm) and specific surface resistivity (0.01-10 Ω/□) to maintain conductivity during deformation.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite structure where a metal complex is combined with specific solvents and additives to form a conductive layer that can be applied on a thermosetting resin layer. This composite material approach allows the conductive layer to achieve both stretchability and maintained conductivity by selecting materials with compatible mechanical properties.

Inventive Principle:

Principle #40Composite materials

2Adaptability or versatility

If the conductive layer is made thinner to improve flexibility, then conformability improves, but electromagnetic wave blocking capability deteriorates

Engineering Contradiction:

ImproveconformabilityVSAvoidelectromagnetic wave blocking

Core Design Contradiction:

Adaptability or versatilityVSObject-affected harmful factors

Solution Approach 1:

The patent optimizes the film thickness parameter of the conductive layer to a specific range (0.1-3.0 μm) that balances flexibility and electromagnetic wave blocking capability. Additionally, the surface resistivity is controlled within 0.01-10 Ω/□ to ensure sufficient conductivity for effective shielding despite the thin film thickness.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent enhances the local quality of the conductive layer by incorporating metal complexes with high conductivity per unit thickness, allowing the thin layer to provide both conformability and effective electromagnetic wave blocking through optimized material composition rather than relying solely on increased thickness.

Inventive Principle:

Principle #3Local quality

3Reliability

If the conductive layer is made thicker to improve conductivity, then electromagnetic wave blocking improves, but flexibility and conformability deteriorate

Engineering Contradiction:

ImproveconductivityVSAvoidflexibility

Core Design Contradiction:

ReliabilityVSAdaptability or versatility

Solution Approach 1:

The patent achieves high conductivity with thin film thickness by changing the material composition parameters, specifically using metal complexes that provide superior conductivity per unit thickness compared to conventional conductive materials. This allows maintaining flexibility while achieving the required electrical properties for effective shielding.

Inventive Principle:

Principle #35Parameter changes

4Ease of manufacture

If a conventional conductive layer is used, then manufacturing is simple, but the material cannot conform to minute irregularities and three-dimensional curved surfaces without gaps

Engineering Contradiction:

Improvemanufacturing simplicityVSAvoidconformability to irregular surfaces

Core Design Contradiction:

Ease of manufactureVSAdaptability or versatility

Solution Approach 1:

The patent employs a flexible thin film approach where the conductive layer is designed with exceptional flexibility and stretchability to conform to complex three-dimensional surfaces and minute irregularities. The thin film structure (0.1-3.0 μm thickness) combined with metal complex formulation allows the layer to drape over curved surfaces without creating gaps, while maintaining manufacturing simplicity through conventional coating processes.

Inventive Principle:

Principle #30Flexible shells and thin films

Data Source

PatentUS20260089904A1Conductive film and electromagnetic wave shielding material using same

Publication Date: 2026.03.26 PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO LTD

AI summary

One aspect of the present invention relates to a conductive film including: a thermosetting resin layer; and a conductive layer on at least a part of at least one surface of the thermosetting resin layer, in which the thermosetting resin layer has an elongation at break at 20° C. of 50% or more, a tensile modulus at 20° C. of 1.0 MPa or more and 200 MPa or less, and a storage modulus at 250° C. of 0.1 MPa or more and 200 MPa or less, a film thickness of the conductive layer is 0.1 μm or more and 3.0 μm or less, the conductive layer contains a metal complex, and the conductive layer has a surface resistivity of 1×10−2Ω/□ or more and 10 Ω/□ or less.