Mask-Guided Quantum Dot Inkjet Printing for Color Precision
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing light emitting device manufacturing methods, such as inkjet printing and OLED evaporation, face challenges with color mixture and precision issues due to unstable droplet formation and high material utilization costs, leading to reduced yield and increased costs.
Innovation Solution
A manufacturing method using a mask plate with hollow portions and modified surfaces to apply quantum dot material ink, allowing for precise control of ink placement and prevention of color mixture through hydrophilic and hydrophobic surface interactions, enabling the formation of accurate light emitting layers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If inkjet printing technology is used to selectively coat quantum dot material ink in sub-pixel grooves, then color saturation and wide color gamut are improved, but droplet instability causes material to deviate from original positions and fall into neighboring sub-pixel areas, resulting in color mixture and reduced yield rate
Solution Approach 1:
The patent introduces a mask plate as an intermediary component between the inkjet printing system and the substrate. The mask plate with precisely positioned holes guides the ink droplets to their intended locations, preventing deviation into neighboring sub-pixel areas. This mediator resolves the contradiction by providing physical constraints that ensure accurate material placement while maintaining the inkjet printing process's ability to produce saturated colors.
Solution Approach 2:
The mask plate implements local quality by having different regions (holes) positioned at specific locations corresponding to sub-pixel grooves. Each hole allows ink to pass only to its designated area, creating localized control over material deposition. This enables precise spatial differentiation where each sub-pixel receives only its intended color material, preventing color mixture while maintaining high color saturation.
2Manufacturing precision
If OLED evaporation method is used to prepare RGB pixels with mask plate coverage, then color precision is maintained, but material utilization rate is lower and cost is extremely high
Solution Approach 1:
The patent replaces the vacuum evaporation mechanical system with a solution-based inkjet printing system combined with a mask plate. Instead of evaporating materials in vacuum chambers with expensive mask plates that require precise alignment and result in material waste, the invention uses liquid ink formulation that can be precisely deposited through mask-guided inkjet printing. This substitution maintains color precision through the mask plate's physical guidance while dramatically improving material utilization by allowing controlled ink flow and reduced overspray.
Solution Approach 2:
The invention changes the physical state parameter of the quantum dot material from vapor phase (evaporation) to liquid phase (ink solution). This parameter change enables the use of inkjet printing technology with mask plate guidance, which provides better material control and utilization compared to vacuum evaporation. The liquid ink formulation allows for precise dosage control and reduced material waste while maintaining the color precision required for RGB pixel formation.
3Manufacturing precision
If precision inkjet printing device is used to guarantee injection precision, then color mixture is prevented, but device investment is too expensive
Solution Approach 1:
The mask plate serves as a cost-effective intermediary that simplifies the precision requirements of the inkjet printing device. Instead of relying on the inkjet device alone to achieve sub-pixel precision through complex control systems and high-precision nozzles, the mask plate provides passive physical guidance that tolerates lower precision in the inkjet device. This intermediary approach maintains injection precision while significantly reducing device investment by allowing the use of less expensive inkjet printing equipment.
Solution Approach 2:
The invention segments the precision function between the mask plate and the inkjet printing device. The mask plate handles the spatial segmentation and positioning function through its physically defined holes, while the inkjet device only needs to provide general droplet deposition capability. This segmentation of functions allows the use of lower-cost inkjet devices while maintaining overall system precision through the mask plate's structural guidance.
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 method improves color precision and reduces costs by preventing ink dispersion and material wastage, enhancing the efficiency and accuracy of light emitting device production.
Implementation Method 1
A manufacturing method using a mask plate with hollow portions and modified surfaces to apply quantum dot material ink, allowing for precise control of ink placement and prevention of color mixture through hydrophilic and hydrophobic surface interactions
Implementation Method 2
A manufacturing method using a mask plate with hollow portions and modified surfaces to apply quantum dot material ink, allowing for precise control of ink placement and prevention of color mixture through hydrophilic and hydrophobic surface interactions
Implementation Method 3
by using a solution method, ink is applied on a surface of the substrate by using the hollow portions
Data Source
AI summary
A manufacturing method for a light emitting device, a light emitting device, and a hybrid light emitting device, the manufacturing method comprises the following steps: step S1: disposing a mask plate having a plurality of hollow portions on a substrate; step S2: applying, by using a solution method, ink on a surface of the substrate by using the hollow portions; and step S3: drying or solidifying the ink on the surface of the substrate to form a light emitting layer or a functional layer.