Anisotropic Conductive Adhesive for Medical Sensor Connections

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing medical technologies face challenges in reliably and cost-effectively contacting sensor units for monitoring body functions, particularly with fine conductive paths that require low electrical resistance and robustness against mechanical movements, such as those found in needle-type sensors used for transcutaneous systems.

Innovation Solution

A method and device utilizing anisotropic conductive adhesives to create electric connections between evaluation units and sensor units, where the adhesive provides conductive properties in one direction and insulating properties in perpendicular directions, allowing for reliable and durable connections despite mechanical movements.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional conductive adhesives or wiring methods are used to connect sensor units to evaluation units, then electrical connections can be established, but the connections exhibit high electrical resistance and lack mechanical robustness against movements

Engineering Contradiction:
Improveconnection reliabilityVSAvoidelectrical resistance
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The patent introduces an anisotropic conductive adhesive as an intermediary material between the sensor unit and evaluation unit. This adhesive contains conductive particles embedded in an adhesive matrix, creating multiple conductive pathways that reduce electrical resistance while maintaining mechanical flexibility to accommodate movements without breaking connections.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The anisotropic conductive adhesive itself is a composite material combining conductive particles (such as metal particles or carbon particles) with an adhesive polymer matrix. This composite structure provides both electrical conductivity through the particles and mechanical adhesion through the polymer, simultaneously addressing electrical resistance and connection reliability requirements.

Inventive Principle:
Principle #40Composite materials

2Reliability

If rigid connection methods are used to ensure mechanical stability, then mechanical robustness is improved, but the device cannot accommodate mechanical movements and deformations

Engineering Contradiction:
Improvemechanical robustnessVSAvoidmechanical flexibility
Core Design Contradiction:
ReliabilityVSAdaptability or versatility

Solution Approach 1:

The patent changes the mechanical parameters of the connection by using a soft, flexible adhesive material instead of rigid wiring or mechanical connectors. The adhesive's viscoelastic properties allow it to deform with mechanical movements while maintaining connection integrity, providing both mechanical robustness and adaptability to movement.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The anisotropic conductive adhesive acts as a compliant intermediary layer that absorbs and distributes mechanical stresses. This intermediary material decouples the sensor unit and evaluation unit, allowing relative movement while maintaining electrical and mechanical connection through its flexible yet adhesive properties.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Manufacturing precision

If precise alignment methods are used to achieve low resistance connections, then manufacturing complexity and cost increase

Engineering Contradiction:
Improveelectrical resistanceVSAvoidmanufacturing complexity
Core Design Contradiction:
Manufacturing precisionVSEase of manufacture

Solution Approach 1:

The patent applies excessive conductive adhesive material between the connection surfaces, ensuring that conductive particles are present in sufficient quantity to create multiple parallel conductive pathways. This excessive application compensates for alignment tolerances and simplifies the manufacturing process by eliminating the need for precise positioning, while still achieving low electrical resistance through the redundant conductive paths.

Inventive Principle:
Principle #16Partial or excessive action

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 enables reliable, low-resistance electrical connections with high mechanical robustness, suitable for long-term use and resistant to sterilization processes, while also being cost-effective and suitable for large-scale manufacturing.

Implementation Method 1

the adhesive provides conductive properties in one direction and insulating properties in perpendicular directions

Methodology Applied
Scientific EffectAnisotropic conduction: Anisotropy

Data Source

PatentEP2679156B1Device for monitoring at least one body function of a user and method for manufacturing the same
Publication Date: 2019.10.02 F HOFFMANN LA ROCHE & CO AG
  • EP2679156B1 patent drawingFigure 1~2
  • EP2679156B1 patent drawingFigure 3~4
  • EP2679156B1 patent drawingFigure 5~6

AI summary

A method for manufacturing a device (110) for monitoring at least one body function of a user is disclosed. The device (110) comprises at least one evaluation unit (112) and at least one sensor unit (114). The method comprises the following steps: a) a step of providing the evaluation unit (112), wherein the evaluation unit (112) has at least one electric contact pad (148) applied to at least one evaluation unit substrate (146), wherein the electric contact pad (148) is electrically connected to at least one electronic device (150) of the evaluation unit (112); b) a step of providing the sensor unit (114), wherein the sensor unit (114) comprises at least one connector part (142), wherein the connector part (142) comprises at least one connector substrate (124) and at least one conductive path (136) applied to the connector substrate (124), wherein the conductive path (136) comprises at least one electrically conductive material (138) and wherein the conductive path (136) has at least one connector portion (140); c) a preparation step, wherein the connector portion (140) is aligned next to the electric contact pad (148) such that the connector portion (140) faces the electric contact pad (148), wherein at least one anisotropic conductive adhesive (166) is provided in between the electric contact pad (148) and the connector portion (140); d) a bonding step, wherein the evaluation unit substrate (146) and the connector substrate (124) are pressed together, wherein the electric contact pad (148) and the connector portion (140) are pressed together, wherein an electric connection of the electric contact pad (148) and the connector portion (140) is created via the anisotropic conductive adhesive (166).