Pyrene Derivative Stabilizes OLED Deposition Rate Variations
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Organic electroluminescent elements prepared using existing light emitting materials exhibit high variations in luminous efficiency, driving voltage, and durability, which are not consistently at the required level, especially with changes in film forming rates during vacuum deposition.
Innovation Solution
Incorporating a pyrene derivative with a specific structure, represented by general formula (I), into the organic electroluminescent element's light emitting layer, which includes a compound with specific substituents and a host material like anthracene, to stabilize performance and reduce dependency on deposition rate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If existing light emitting materials are used with conventional vacuum deposition methods, then the organic electroluminescent element can be manufactured, but the luminous efficiency, driving voltage, and durability show high variations and do not reach required performance levels
Solution Approach 1:
The patent introduces a novel compound structure (formula I) with specific molecular architecture including heteroatom-containing six-membered rings and aromatic hydrocarbon groups, which fundamentally changes the material parameters to achieve consistent high performance across different deposition rates
Solution Approach 2:
The patent employs composite material strategy by combining the novel compound of formula (I) with host materials and dopants in the light-emitting layer, creating a multi-component system that maintains performance stability regardless of deposition rate variations
2Productivity
If film forming rate is changed during vacuum deposition, then deposition time and productivity can be adjusted, but the luminous efficiency, driving voltage, and durability of the organic electroluminescent element show high variations
Solution Approach 1:
The patent changes the chemical parameters of the light-emitting material to formula (I), which has molecular structure characteristics that enable stable film formation and charge transport across a wide range of deposition rates, thereby decoupling productivity from performance reliability
3Ease of manufacture
If film forming rate is changed during vacuum deposition, then manufacturing flexibility can be improved, but the luminous efficiency, driving voltage, and durability show high variations and fail to reach required levels
Solution Approach 1:
The patent modifies the material parameters by introducing compound (I) with specific structural features that provide process window flexibility, allowing manufacturers to vary deposition rates without compromising luminous efficiency control or final product quality
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 organic electroluminescent element achieves improved luminous efficiency, driving voltage, and durability with reduced dependency on deposition rate, making it suitable for display and illumination devices.
Implementation Method 1
utilize, for light emitting, energy of the exciton generated as a result of recombination of electrons injected from a cathode and holes injected from an anode in the organic layer
Implementation Method 2
a light emitting layer including the light emitting material is formed at a film forming rate of 5 angstroms/s to 30 angstroms/s according to a vacuum deposition method
Data Source
AI summary
An organic electroluminescent element including a substrate, a pair of electrodes including an anode and a cathode, disposed on the substrate, and at least one organic layer including a light emitting layer, disposed between the electrodes, in which at least one kind of compound represented by the following general formula (I) is contained in any layer of the at least one organic layer. The organic electroluminescent element has good luminous efficiency, driving voltage, and driving durability, and has low dependence of such performance on a deposition rate:wherein X, Q, R1 to R8 are as defined in the application.