Expandable Adhesive Tape for LCD Backlight Sealing
Solution Overview
Problem
In liquid crystal display (LCD) backlight modules, light leakage occurs due to gaps between the light guide plate and the top plate, which existing adhesive tapes fail to fully seal, leading to reduced visual performance.
Innovation Solution
An adhesive tape with an expandable structure layer that expands when heated, filling the gap between the light guide plate and the top plate, comprising a cured adhesive layer with thermal expansion microstructures and protective layers, and a heating structure to control expansion, ensuring a secure seal.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional adhesive tapes are used to seal the gap between the light guide plate and top plate, then the structure is simple and easy to manufacture, but light leakage occurs due to incomplete sealing
Solution Approach 1:
The adhesive tape incorporates an expandable structure layer containing thermal expansion microstructures that can dynamically change volume in response to temperature changes. When heated, these microstructures expand to fill gaps and improve sealing performance, while returning to their original state when cooled, enabling reversible adjustment of the sealing capability.
Solution Approach 2:
The adhesive tape utilizes temperature as a controllable parameter to trigger volume changes in the expandable structure layer. By changing the temperature, the sealing performance can be adjusted - heating causes expansion for better sealing, while cooling allows contraction for easier installation or adjustment.
2Reliability
If the adhesive tape is made thicker to ensure complete sealing, then light leakage is prevented, but the manufacturing precision and assembly difficulty increase
Solution Approach 1:
Rather than using a statically thick adhesive tape, the invention employs a thinner tape with dynamically expandable microstructures. These microstructures remain compact during installation for precise positioning, then expand when heated to completely fill the gap, achieving both precision and reliability.
Solution Approach 2:
The thermal expansion microstructures undergo a phase transition or significant volume change when heated, transforming from a compact state suitable for precise assembly to an expanded state that completely fills the gap for effective sealing, eliminating the need for thick static structures.
3Adaptability or versatility
If a fixed-size adhesive tape is used, then the manufacturing process is simple, but it cannot adapt to variations in gap size between different assemblies
Solution Approach 1:
The adhesive tape incorporates expandable microstructures that can dynamically adjust their volume to match different gap sizes. This dynamic adaptability allows a single tape design to work across various assembly tolerances and gap variations without requiring custom-sized tapes for each application.
Solution Approach 2:
By using temperature-controlled expansion, the adhesive tape can adapt to different gap sizes through parameter changes rather than physical customization. The same tape structure can expand to fill small or large gaps as needed, providing versatility while maintaining manufacturing simplicity.
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
Effectively prevents light leakage by expanding to fill the gap between the light guide plate and the top plate, enhancing the visual performance of LCDs by ensuring a complete seal.
Implementation Method 1
an expandable structure layer on a side of the adhesive body layer and configured to fill a gap between the adhesive tape and a light guide plate of a backlight module through an expansion of the expandable structure layer
Implementation Method 2
the expandable structure layer includes: a cured adhesive layer having a light-shielding function; and a plurality of thermal expansion microstructures dispersed in the cured adhesive layer
Implementation Method 3
Each of the thermal expansion microstructures includes: a housing layer forming a sealed space and configured to soften when the housing layer is heated; and a foaming agent in the sealed space and configured to generate a gas when the foaming agent is heated, to expand the housing layer
Implementation Method 4
the adhesive tape further includes a heating structure layer configured to heat the expandable structure layer. The heating structure layer includes a resistance wire
Data Source
AI summary
The present disclosure provides an adhesive tape, a backlight module, a display device, and a method for manufacturing a backlight module. The adhesive tape includes: an adhesive body layer; an expandable structure layer on a side of the adhesive body layer and configured to fill a gap between the adhesive tape and a light guide plate of a backlight module through an expansion of the expandable structure layer.