KR-20260067105-A - Electroluminescent Acoustic Composition and Electroluminescent Sound Display

Abstract

The present invention relates to an electrophotoacoustic composition and an electrophotoacoustic device. By adding BST, the dielectric constant can be improved and the electroluminescence performance can be enhanced. An electrophotoacoustic composition according to an embodiment of the present invention comprises a polymer resin; a phosphor and BST (Barium Strontium Titanate).

Inventors

• 배진우
• 오승주
• 윤재욱

Assignees

• 한국기술교육대학교 산학협력단

Dates

Publication Date

20260512

Application Date

20241105

Claims (12)

1. Polymer resin; Phosphorescent material and Containing BST (Barium Strontium Titanate), Electrophotoacoustic composition.
2. In paragraph 1, The content of the above BST is 5 to 20 parts by weight per 100 parts by weight of the above polymer resin, Electrophotoacoustic composition.
3. In paragraph 1, The content of the phosphor is 250 to 350 parts by weight per 100 parts by weight of the polymer resin, Electrophotoacoustic composition.
4. In paragraph 1, The above phosphor is copper-doped zinc sulfide (ZnS:Cu), Electrophotoacoustic composition.
5. In paragraph 1, The above polymer resin is PVDF-TrFE (Polyvinylidene fluoride-trifluoroethylene), Electrophotoacoustic composition.
6. A step of preparing a mixture by mixing a polymer resin, a phosphor, and BST (Barium Strontium Titanate); A step of forming a coating layer by applying the above mixture and A step comprising drying the above coating layer, Method for manufacturing an electrophotoacoustic layer.
7. In paragraph 6, The content of the BST in the above mixture is 5 to 20 parts by weight per 100 parts by weight of the polymer resin, Method for manufacturing an electrophotoacoustic layer.
8. In paragraph 6 The content of the phosphor in the above mixture is 250 to 350 parts by weight per 100 parts by weight of the polymer resin, Method for manufacturing an electrophotoacoustic layer.
9. It includes an electrode and an electrophotoacoustic layer connected to the electrode, The above electrophotoacoustic layer is that of claim 6, Electrophotoacoustic device.
10. Step of preparing the electrode; A step of forming an electrophotoacoustic layer using the above electrophotoacoustic composition and The method includes the step of placing the electrode on the electrophotoacoustic layer, The above electrophotoacoustic composition is that of claim 1, Method for manufacturing an electrophotoacoustic device.
11. In Paragraph 10, In the above electrophotoacoustic composition, the content of the BST is 5 to 20 parts by weight per 100 parts by weight of the polymer resin, Method for manufacturing an electrophotoacoustic device.
12. In paragraph 10 In the above electrophotoacoustic composition, the content of the phosphor is 250 to 350 parts by weight per 100 parts by weight of the polymer resin, Method for manufacturing an electrophotoacoustic device.

Description

Electroluminescent Acoustic Composition and Electroluminescent Sound Display Including BST The present invention relates to an electrophotoacoustic composition and an electrophotoacoustic device. By adding BST, the dielectric constant can be improved and the electroluminescence performance can be enhanced. The present invention is the result of research conducted with funding from the government (Ministry of Science and ICT) and supported by the National Research Foundation of Korea (RS-2024-00348475). Electro-optical devices are attracting attention as a new type of display alongside the recent advancements in wearable electronic devices. While conventional displays have been limited primarily to the function of conveying visual information, there is a growing need for multi-functional displays that combine sound and light-emitting functions to enrich interaction with users. Conventional electroluminescent (EL) devices have attracted much attention as devices with a simple structure, lightweight nature, long lifespan, and excellent deformation capabilities. These devices are primarily based on silver nanowires or highly conductive materials and exhibit high luminescence when voltage is applied, but they have limitations in terms of flexibility. Additionally, while conventional flexible electrodes, such as hydrogel electrodes, offer high flexibility, they have the problem of unstable performance due to sensitivity to changes in humidity and temperature. Accordingly, research has been conducted to develop electrophotoacoustic devices that simultaneously satisfy flexibility and luminescence performance. However, conventional electrophotoacoustic devices have found it difficult to achieve both excellent brightness and sound pressure. FIG. 1 is a flowchart of a method for manufacturing an electrophotoacoustic layer according to an embodiment of the present invention. Figure 2 is a chemical structure diagram of copper-doped zinc sulfide (ZnS:Cu). Figure 3 is a chemical structure diagram of BST. FIG. 4 is a flowchart of a method for manufacturing an electrophotoacoustic device according to an embodiment of the present invention. Figure 5 shows the luminance measurement results according to voltage of the example and comparative example. Figure 6 shows the sound pressure measurement results according to the voltage of the example and comparative example. Figure 7 shows the results of luminance and sound pressure measurements according to the weight ratio of BST included in the polymer resin. FIG. 8 is a photograph of the operation of an electrophotoacoustic device according to an embodiment of the present invention. Hereinafter, preferred embodiments of the present invention are described as follows with reference to the attached drawings. However, embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below. Furthermore, embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art. An electrophotoacoustic composition according to an embodiment of the present invention comprises a polymer resin; a phosphor and BST (Barium Strontium Titanate). The above polymer resin forms the basic structure of the electroluminescent film speaker in this invention and enables luminescence and acoustic properties in response to an electric field. The above polymer resin may be any one of PVDF-TrFE (Polyvinylidene fluoride-trifluoroethylene), PVDF (Polyvinylidene fluoride), and PZT (Lead Zirconate Titanate). PVDF-TrFE is a ferroelectric polymer that can maintain polarization in an electric field, possesses excellent piezoelectric properties, and has excellent flexibility and strength, making it more preferable. The above phosphor is a material that absorbs energy supplied from the outside and emits it as light. The above phosphor may be copper-doped zinc sulfide (ZnS:Cu), YAG (Yttrium Aluminum Garnet), BaAl₂O₄ , etc. , among which copper-doped zinc sulfide is more preferable as it has excellent luminous efficiency, durability, and stability. The content of the phosphor may be 250 to 350 parts by weight, preferably 280 to 320 parts by weight, per 100 parts by weight of the polymer resin. If the content of the phosphor is too high, the luminescence performance increases but the mechanical properties and acoustic performance decrease, and conversely, if the content is too low, there is a problem that the luminescence performance decreases. The above-mentioned BST (Barium Strontium Titanate) is a material with excellent dielectric and piezoelectric properties. The present invention can improve electrical and acoustic performance by adding BST. BST can be mixed with a polymer resin (PVDF-TrFE) to enhance responsiveness to an electric field. Specifically, thanks to the high dielectric constant of BST, the electrical sensitivity of the entire film increases, and stronger