Carbon Nanotube Conductive Lines for Touch Panel Durability

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional capacitance-type touch panels using indium tin oxide (ITO) lines suffer from poor mechanical durability, low chemical endurance, uneven resistance, and low transparency, resulting in low sensitivity, accuracy, and brightness.

Innovation Solution

A touch panel design incorporating carbon nanotube wires for the conductive lines, which are formed by pulling out carbon nanotube structures from a super-aligned array and treated with mechanical force, providing superior toughness and high mechanical strength, and connected to a capacitive sensing member for improved sensitivity and accuracy.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If indium tin oxide (ITO) lines are used in conventional capacitance-type touch panels, then the touch panel can be manufactured with existing materials, but the mechanical durability is poor and chemical endurance is low

Engineering Contradiction:

Improvemechanical durabilityVSAvoidmanufacturing complexity

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent changes the material parameter from indium tin oxide (ITO) to carbon nanotubes (CNT), fundamentally altering the conductive material's properties to achieve superior mechanical durability and chemical endurance while maintaining electrical conductivity for touch panel operation

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent employs carbon nanotube wires as composite conductive elements, combining the mechanical strength and chemical stability of carbon nanotubes with the electrical conductivity required for capacitive sensing, creating a material that outperforms traditional ITO in both durability and functionality

Inventive Principle:

Principle #40Composite materials

2Manufacturing precision

If indium tin oxide (ITO) lines are used in conventional capacitance-type touch panels, then the touch panel can be manufactured with existing materials, but the resistance is uneven

Engineering Contradiction:

Improveresistance uniformityVSAvoidmanufacturing complexity

Core Design Contradiction:

Manufacturing precisionVSEase of manufacture

Solution Approach 1:

The patent changes the material parameter from ITO to carbon nanotubes, which inherently provide more uniform electrical resistance due to their consistent one-dimensional conductive structure, eliminating the resistance unevenness observed in conventional ITO-based touch panels

Inventive Principle:

Principle #35Parameter changes

3Illumination intensity

If indium tin oxide (ITO) lines are used in conventional capacitance-type touch panels, then the touch panel can be manufactured with existing materials, but the transparency is low

Engineering Contradiction:

ImprovebrightnessVSAvoidmanufacturing complexity

Core Design Contradiction:

Illumination intensityVSEase of manufacture

Solution Approach 1:

The patent changes the material parameter from ITO to carbon nanotubes, which offer superior optical transparency and higher light transmission properties, thereby improving the brightness and visual quality of the touch panel while maintaining electrical functionality

Inventive Principle:

Principle #35Parameter changes

4Measurement precision

If indium tin oxide (ITO) lines are used in conventional capacitance-type touch panels, then the touch panel can be manufactured with existing materials, but the sensitivity and accuracy are low

Engineering Contradiction:

Improvetouch accuracyVSAvoidmanufacturing complexity

Core Design Contradiction:

Measurement precisionVSEase of manufacture

Solution Approach 1:

The patent changes the material parameter from ITO to carbon nanotubes, which provide more consistent electrical properties and better capacitive coupling characteristics, thereby enhancing the sensitivity and accuracy of touch detection while maintaining manufacturability through established fabrication processes

Inventive Principle:

Principle #35Parameter changes

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 carbon nanotube-based touch panel offers enhanced durability, sensitivity, accuracy, and brightness, with the ability to form flexible touch panels and reduce production costs through a simple, low-cost, and environmentally safe fabrication method.

Implementation Method 1

The carbon nanotube wires each include a plurality of carbon nanotubes... at least one of the first and second pluralities of conductive lines includes carbon nanotube wires

Methodology Applied

Scientific EffectElectrical conduction: Conduction (electrical)

Data Source

PatentUS8243030B2Touch panel and display device using the same

Publication Date: 2012.08.14 HON HAI PRECISION INDUSTRY CO LTD

AI summary

A touch panel includes a first conductive layer, a second conductive layer and a capacitive sensing member. The first conductive layer includes a plurality of first conductive lines. The second conductive layer separated from the first conductive layer includes a plurality of second conductive lines. One of the plurality of conductive lines is located above the other plurality of conductive lines. The capacitive sensing member is connected to the first conductive lines. At least one of the first and second pluralities of conductive lines includes carbon nanotube wires. The carbon nanotube wires each include a plurality of carbon nanotubes. Further, a display device using the above-described touch panel is also included.