Copolyestercarbonate Substrate for Flexible Conductive Electronics

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conductive substrates, particularly those made of transparent conductive metal oxides, face limitations in flexibility and impact resistance, and the roll-to-roll process is hindered by the low glass transition temperature of polyethylene terephthalate, which restricts their application in flexible electronics manufacturing.

Innovation Solution

A polymeric substrate with a glass transition temperature of at least 130°C, made from a polymeric block copolyestercarbonate derived from resorcinol or alkylresorcinol isophthalate-terepthalate, is used, combined with a conductive nanostructured or microstructured material, where the substrate is heated above its glass transition temperature and subjected to pressure to adhere the conductive material effectively.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If transparent conductive metal oxides (TCOs) are used for conductive substrates, then electrical conductivity and transparency are improved, but flexibility and impact resistance deteriorate

Engineering Contradiction:
Improveelectrical conductivityVSAvoidflexibility
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The patent uses a composite structure combining a polymeric substrate (providing flexibility) with conductive nanostructured or microstructured material (providing electrical conductivity). This composite approach allows the material to simultaneously achieve the electrical performance of TCOs while gaining the flexibility and impact resistance of polymers, directly resolving the contradiction between conductivity and flexibility

Inventive Principle:
Principle #40Composite materials

2Ease of manufacture

If PET substrate is used in roll-to-roll process, then ease of manufacture is improved, but glass transition temperature is too low (78°C) limiting manufacturing temperature

Engineering Contradiction:
Improveroll-to-roll process compatibilityVSAvoidglass transition temperature
Core Design Contradiction:
Ease of manufactureVSTemperature

Solution Approach 1:

The patent changes the key parameter of glass transition temperature by replacing PET with a polymeric block copolyestercarbonate that has a glass transition temperature of at least 130°C. This parameter change enables the substrate to withstand higher manufacturing temperatures in the roll-to-roll process while maintaining ease of manufacture and flexibility

Inventive Principle:
Principle #35Parameter changes

3Reliability

If conductive nanostructured material is adhered to polymeric substrate, then electrical conductivity is improved, but adhesion strength deteriorates due to heating and pressure requirements

Engineering Contradiction:
Improveelectrical conductivityVSAvoidadhesion strength
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The patent utilizes the glass transition phase transition of the polymeric substrate (at least 130°C) to enhance adhesion. By heating the substrate above its glass transition temperature, the polymer chains become more mobile and can better conform to and bond with the conductive nanostructured material, improving adhesion strength while maintaining electrical conductivity

Inventive Principle:
Principle #36Phase transitions

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

This approach results in an electrically-conductive material with improved properties such as ultraviolet resistance, transparency, light transmission, and chemical resistance, while maintaining a low sheet resistance of less than 20 ohms per square, enhancing the material's suitability for flexible electronics.

Implementation Method 1

the substrate is heated above its glass transition temperature and subjected to pressure to adhere the conductive material effectively

Methodology Applied
Scientific EffectGlass transition:

Implementation Method 2

applying pressure such that the substrate and the micro- or nanostructures are pressed together

Methodology Applied
Scientific EffectPressure-sensitive adhesion:

Data Source

PatentEP3560000B1Electrically-conductive copolyestercarbonate-based material
Publication Date: 2021.04.14 SHPP GLOBAL TECH BV
  • EP3560000B1 patent drawingFigure 1
  • EP3560000B1 patent drawingFigure 2
  • EP3560000B1 patent drawingFigure 3A

AI summary

An electrically-conductive material includes a polymeric substrate and a conductive nanostructured or microstructured material adhered to at least one surface of the polymeric substrate. The polymeric substrate includes a polymeric block copolyestercarbonate derived from resorcinol or alkylresorcinol isophthalate-terepthalate. The polymeric block copolyestercarbonate has a glass transition temperature of at least 130 degrees Celsius (°C) and a sheet resistance of less than 20 ohms (Ω) per square (sq). Methods for making an electrically-conductive material are also described. The electrically-conductive material may exhibit improved properties, including but not limited to one or more of inherent ultraviolet resistance, transparency, light transmission properties, chemical resistance and/or sheet resistance.