Transparent Adhesive Layer Gravity Rotation Bonding

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current optical bonding processes for transparent layers, such as in displays, are hindered by the challenge of air bubble formation, which leads to suboptimal optical quality and increased production costs due to the need for complex and expensive vacuum-based methods.

Innovation Solution

A method involving the application of a curable, transparent adhesive in a liquid phase to a display unit, followed by rotation to form a teardrop shape under gravity, ensuring air-bubble-free distribution between the display and input units, utilizing additives like two-component silicone or UV-curable acrylate for easy curing and integrated filler bodies for precise layer thickness, eliminating the need for vacuum steps and enhancing optical clarity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If vacuum-based bonding methods are used to eliminate air bubbles, then optical quality is improved, but production cost and process complexity increase

Engineering Contradiction:
Improveoptical qualityVSAvoidprocess complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The harmful air bubbles are extracted and removed from the adhesive layer by rotating the display unit, allowing bubbles to migrate to the edge and be eliminated, achieving high optical quality without vacuum equipment

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

Instead of using vacuum to remove air bubbles from the adhesive layer, the method inverts the approach by using gravity and rotation to actively transport bubbles to the edge where they can escape, simplifying the process while maintaining optical quality

Inventive Principle:
Principle #13The other way round (Inversion)

2Manufacturing precision

If vacuum-based bonding methods are used to eliminate air bubbles, then optical quality is improved, but production cost increases

Engineering Contradiction:
Improveoptical qualityVSAvoidproduction cost
Core Design Contradiction:
Manufacturing precisionVSEase of manufacture

Solution Approach 1:

The method replaces expensive vacuum bonding equipment with simple, low-cost components such as rotation mechanisms and adhesive materials, significantly reducing production cost while achieving the same optical quality through gravitational bubble removal

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

3Strength

If adhesive is applied to bond transparent layers, then bonding strength is improved, but air bubble formation increases

Engineering Contradiction:
Improvebonding strengthVSAvoidair bubble formation
Core Design Contradiction:
StrengthVSObject-generated harmful factors

Solution Approach 1:

The adhesive is applied in advance to the entire bonding surface before assembly, ensuring complete coverage and strong bonding potential, while the subsequent rotation process preliminarily removes air bubbles to prevent them from interfering with the final bond quality

Inventive Principle:
Principle #10Preliminary action

4Object-generated harmful factors

If complex vacuum processes are used for bonding, then air bubble elimination is improved, but manufacturing time increases

Engineering Contradiction:
Improveair bubble eliminationVSAvoidmanufacturing time
Core Design Contradiction:
Object-generated harmful factorsVSLoss of time

Solution Approach 1:

The method skips the time-consuming vacuum chamber setup and pumping phases by using a direct rotation approach that rapidly transports air bubbles to the edge in seconds, significantly reducing the air bubble elimination time while maintaining effectiveness

Inventive Principle:
Principle #21Skipping (Rushing through)

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 method enables cost-effective, bubble-free optical bonding, improving the optical brilliance and mechanical stability of displays, particularly suitable for industrial applications like automotive displays, by ensuring air bubble elimination and precise adhesive layer formation without the need for expensive vacuum processes.

Implementation Method 1

After the display unit has been rotated and, after a deformation and a contraction of the transparent adhesive layer into a teardrop shape caused by gravity

Methodology Applied
Scientific EffectGravity: Gravitation

Implementation Method 2

The hardening of the adhesive takes place by irradiation with light which falls from a transparent side of the plate

Methodology Applied
Scientific EffectUV curing: Photopolymerisation

Data Source

PatentEP2695923B1Method for transparent bonding of transparent layers
Publication Date: 2018.07.04 PIOPTIX
  • EP2695923B1 patent drawingFigure 1
  • EP2695923B1 patent drawingFigure 2~4
  • EP2695923B1 patent drawingFigure 5A~5B

AI summary

Transparent bonding of transparent layers, comprises (i) applying a transparent adhesive to a connecting surface (31) on a display unit (3) to form a transparent adhesive layer, and (ii) rotating the display unit around a pivotal axis, (iii) molding the transparent adhesive layer and contracting the transparent adhesive layer, and (iv) joining the connecting surface and the transparent adhesive layer on a support surface (51) of an input unit (5), pressing the display unit on the input unit, and distributing the transparent adhesive layer on the predetermined adhesive area of the input unit. Transparent bonding of transparent layers to obtain a curable transparent adhesive (1), comprises (i) applying a transparent adhesive, which is present in liquid or viscous phase, to a connecting surface (31) on a top side of a display unit (3) to form a transparent adhesive layer, and (ii) rotating the display unit to 180[deg] around a pivotal axis, (iii) molding the transparent adhesive layer and contracting the transparent adhesive layer at least partially through gravitational force to obtain droplet form, and (iv) joining together the connecting surface and the transparent adhesive layer, which is applied to the connecting surface, on a support surface (51) of an input unit (5), pressing the display unit onto the underlying input unit through gravitational force, and distributing the transparent adhesive layer, which is arranged between the input unit and the display unit, on the predetermined adhesive area of the input unit by pressing, or (ia) applying the transparent adhesive, which is present in liquid or viscous phase, on the predetermined adhesive area of the support surface of the input unit, (iia) placing the display unit (3) with a side edge on the adhesive layer in a predetermined tilt angle to the support surface of the input unit on the input unit, and (iiia) tilting down the display unit to side edge as a pivotal axis in the direction of the input unit, and distributing the transparent adhesive, which is arranged between the input unit and the display unit, in the form of a propagation wave without air bubbles on the predetermined adhesive area of the input unit by and during the tilting movement. The transparent adhesive layer is pointed downwards, after the rotation of the display unit. An independent claim is also included for a display device (100) comprising the display unit and the input unit, where the curable transparent adhesive layer is arranged in the vertical direction between the display unit and the input unit, and the curable transparent adhesive layer is present without air bubbles.