Graphene Oxide Heat Dissipation Sheet for Foldable Devices

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional artificial graphite films are not suitable for foldable/rollable electronic devices due to voids between layers, which hinder effective heat transfer and durability, especially around hinge structures where repetitive folding occurs.

Innovation Solution

A heat dissipation sheet composed of graphene oxide particle layers with different sizes and a fine crease structure, combined with polyacrylonitrile (PAN) particles, is developed to enhance thermal conductivity and tensile strength, allowing for efficient heat transfer and durability during repetitive folding.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If conventional artificial graphite film is used as heat dissipation sheet, then mass productivity and price competitiveness are improved, but heat transfer performance and durability are worsened due to numerous voids between layers

Engineering Contradiction:

Improvemass productivityVSAvoidheat transfer performance

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent uses composite materials by combining graphene oxide particles of different sizes (first size: 1-10 μm, second size: 0.1-1 μm) in specific weight ratios (first particles: 30-70 wt%, second particles: 70-30 wt%). This composite structure eliminates voids between layers while maintaining high heat conductivity and mechanical strength, resolving the contradiction between mass productivity and heat transfer performance.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent applies local quality by creating a multi-scale particle distribution where larger particles (1-10 μm) provide structural framework and smaller particles (0.1-1 μm) fill interstitial spaces. This local optimization of particle sizes ensures complete void elimination in critical heat transfer paths while maintaining overall film density and mechanical integrity.

Inventive Principle:

Principle #3Local quality

2Ease of manufacture

If conventional artificial graphite film is used, then manufacturing simplicity is improved, but mechanical durability during repetitive folding is worsened due to insufficient tensile strength and elongation rate

Engineering Contradiction:

Improvemanufacturing simplicityVSAvoidtensile strength

Core Design Contradiction:

Ease of manufactureVSStrength

Solution Approach 1:

The patent employs composite materials with dual-size graphene oxide particles where larger particles (1-10 μm) form a robust structural network providing tensile strength, while smaller particles (0.1-1 μm) fill gaps and enhance inter-particle bonding. This composite architecture achieves elongation rate >5% and tensile strength >10 MPa, enabling durability during repetitive folding while maintaining manufacturing simplicity through a single-layer structure.

Inventive Principle:

Principle #40Composite materials

3Adaptability or versatility

If conventional artificial graphite film is used, then cost effectiveness is improved, but heat dissipation efficiency is worsened due to voids larger than 5 μm

Engineering Contradiction:

Improvecost effectivenessVSAvoidheat dissipation efficiency

Core Design Contradiction:

Adaptability or versatilityVSTemperature

Solution Approach 1:

The patent utilizes porous materials concept in reverse by eliminating pores/voids through careful particle size selection. The larger particles (1-10 μm) create a percolating network for heat conduction, while smaller particles (0.1-1 μm) fill void spaces, achieving void-free structure with enhanced heat dissipation efficiency. This maintains cost effectiveness by using graphene oxide rather than more expensive materials like hBN or metal foils.

Inventive Principle:

Principle #31Porous materials

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 provides improved heat dissipation performance and mechanical durability, maintaining effective heat transfer even after multiple folding cycles, outperforming conventional graphite sheets in thermal conductivity and elongation rate.

Implementation Method 1

a heat dissipation sheet composed of graphene oxide particle layers with different sizes and a fine crease structure, combined with polyacrylonitrile (PAN) particles, is developed to enhance thermal conductivity and tensile strength, allowing for efficient heat transfer

Methodology Applied

Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 2

performing annealing on the initial film

Methodology Applied

Scientific EffectAnnealing: Annealing

Data Source

PatentUS20230365412A1Heat dissipation sheet for electronic device and manufacturing method therefor

Publication Date: 2023.11.16 SAMSUNG ELECTRONICS CO LTD

AI summary

A heat dissipation sheet is provided. The heat dissipation sheet has a plurality of graphene oxide particle layers including first graphene oxide particles having an average diameter of a first size and second graphene oxide particles having an average diameter of a second size, and a fine crease structure including pores with a thickness of less than 2 μm between the plurality of graphene oxide particle layers. Additionally, a manufacturing method for the heat dissipation sheet and a mobile communication device comprising the heat dissipation sheet are provided.