Broadband spectrum antireflection film for flexible display panel and preparation method thereof
Through the multi-layer structure of wide spectrum anti-reflection film, the problem of high reflectivity of flexible AMOLED display panels is solved, and better display effect and energy efficiency is achieved. It is suitable for large-size flexible AMOLED display panels.
Patent Information
- Application Number
- CN202510485598.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-17
- Publication Date
- 2025-07-11
AI Technical Summary
The existing flexible AMOLED display panels have the problem of high reflectivity, which affects the display effect and power consumption, especially in large sizes.
A multi-layer structure of wide spectral anti-reflection film is designed, including substrate, PDMS, PI and silicon nitride film layers, prepared by ultrasonic cleaning, spin coating, plasma treatment and PECVD deposition, and optimized film layer thickness and material selection to enhance adhesion and transmittance.
It significantly reduces reflectivity, improves light transmittance, improves display effect and reduces power consumption. It is suitable for large-size flexible AMOLED display panels.
Smart Images
Figure CN120302767A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of flexible display, and in particular to a broadband antireflection film for a flexible display panel and a preparation method thereof. Background Art
[0002] Flexible AMOLED display products for mobile terminals, as a new display technology, show a development trend of flexibility, miniaturization, and diversification. First, the panel form is flexible. OLED is a technology for realizing flexible display and is widely used in newly released display terminals. Enterprises such as Apple, Huawei, Samsung, VIVO, and Xiaomi have all adopted OLED screens in their newly released mobile phones, realizing flexible display design processes such as ring screens, waterfall screens, and folding screens.
[0003] With the continuous development of new display technologies and mobile terminal technologies, the folding screen mobile phone market is becoming increasingly mature, and the demand for folding screen mobile phones from users is growing rapidly. This trend not only reflects users' pursuit of emerging technologies but also their demand for higher-performance mobile phones. The development trend of flexible AMOLED display products is large-size bendable and flexible. However, power consumption and battery life become a core technology after increasing the size. Increasing the thickness of the battery will inevitably affect the bending performance of the display screen. To achieve the flexible concept, it is necessary to start from reducing the power consumption of the display. Currently, Korean panel manufacturers have launched the COE technology, which can reduce power consumption by 10% - 20% on the premise that the thickness of the display module remains basically unchanged, but it has the problem of high reflectivity.
[0004] Therefore, it is of great significance to develop a broadband antireflection film for a flexible display panel and a preparation method thereof. Summary of the Invention
[0005] The purpose of the present invention is to design a broadband antireflection film for a flexible display panel and a preparation method thereof to solve the above problems.
[0006] The present invention achieves the above purpose through the following technical solutions: A broadband antireflection film for a flexible display panel includes a substrate, a first film layer, a second film layer, and a third film layer arranged in sequence from one end to the other end. The first film layer is made of PDMS, the second film layer is made of PI, and the third film layer is made of silicon nitride.
[0007] Further, the substrate is a glass substrate or an OLED light-emitting module.
[0008] Further, the thickness of the first film layer is 97 - 117 nm, the thickness of the second film layer is 70 - 90 nm, and the thickness of the third film layer is 33 - 53 nm.
[0009] A preparation method of a broadband antireflection film for a flexible display panel includes the following steps: S1. Ultrasonically clean the substrate and dry the cleaned substrate. S2. Spin-coat a first flexible optical film layer on the dried substrate and then heat-cure it. S3. Perform plasma treatment on the first flexible optical film layer to enhance the adhesion between the film layers. S4. Spin-coat a second flexible optical film layer on the treated first flexible optical film layer and bake it for curing. S5. Perform plasma treatment or adhesion layer treatment on the second flexible optical film layer to enhance the adhesion between the film layers. S6. Deposit a third flexible optical film layer on the second flexible optical film layer by PECVD. S7. Package the device.
[0010] Specifically, the plasma treatment method in step S3 is as follows: Place the first flexible optical film layer in a plasma treatment device and etch it with oxygen at a power of 75 W for 3 minutes.
[0011] Specifically, the plasma treatment method in step S5 is as follows: Place the second flexible optical film layer in a plasma treatment device; etch it with oxygen at a power of 55 W for 3 minutes.
[0012] The beneficial effects of the present invention are as follows: By first ultrasonically cleaning the substrate, drying the cleaned substrate, spin-coating a first flexible optical film layer on it and then heat-curing it, spin-coating a second flexible optical film layer on the basis of performing plasma treatment on the first film layer and then baking it to form a film, performing plasma treatment / preparing an adhesion layer for lamination on this basis, and then depositing a third film layer on it by PECVD; wherein, the thickness of the first film layer is 97 - 117 nm, the thickness of the second film layer is 70 - 90 nm, and the thickness of the third film layer is 33 - 53 nm; through this technical solution, it is possible to effectively reduce light reflection, enhance light transmittance, and thus improve the display effect and energy efficiency. Description of the Drawings
[0013] Figure 1 It is a schematic optical structure diagram of the broadband antireflection film applied to the flexible AMOELD panel of the present invention; Figure 2 It is a schematic structure diagram of the broadband antireflection film applied to the flexible AMOELD panel of the present invention; Figure 3 It is a comparison diagram of the reflection spectra of Example 1 and Example 4 of the broadband antireflection film applied to the flexible AMOELD panel of the present invention.
[0014] In the figure: 1 - substrate; 2 - first film layer; 3 - second film layer; 4 - third film layer. Detailed Embodiments
[0015] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. The components of the embodiments of the present invention usually described and illustrated in the drawings here can be arranged and designed in various different configurations.
[0016] Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.
[0017] It should be noted that like reference numerals and letters denote like items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.
[0018] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "upper", "lower", "inner", "outer", "left", "right", etc. are based on the orientation or positional relationships shown in the drawings, or the orientation or positional relationships in which the inventive product is customarily placed during use, or the orientation or positional relationships commonly understood by those skilled in the art. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention.
[0019] In addition, the terms "first", "second", etc. are only used for descriptive distinction and should not be construed as indicating or implying relative importance.
[0020] In the description of the present invention, it should also be noted that unless otherwise clearly specified and limited, terms such as "arranged" and "connected" should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0021] The following will provide a detailed description of the specific embodiments of the present invention with reference to the accompanying drawings.
[0022] Such as Figure 1As shown, the reflection of the interface is modulated by the reflectivity of different film layers, and at the same time, the interference modulation is carried out in the required window band by controlling the film layer thickness, so as to achieve better antireflection performance compared with the single-layer antireflection film.
[0023] As Figure 2 shown, a wide-spectrum antireflection film for a flexible display panel includes a substrate 1, a first film layer 2, a second film layer 3, and a third film layer 4 sequentially arranged from one end to the other end. The first film layer 2 is made of PDMS, the second film layer 3 is made of PI, and the third film layer 4 is made of silicon nitride.
[0024] In some embodiments, the substrate is a glass substrate or an OLED light-emitting module.
[0025] In some embodiments, the thickness of the first film layer is 97 - 117 nm, the thickness of the second film layer is 70 - 90 nm, and the thickness of the third film layer is 33 - 53 nm.
[0026] A preparation method of a wide-spectrum antireflection film for a flexible display panel includes the following steps: S1. Ultrasonically clean the substrate and perform a drying treatment on the cleaned substrate; S2. Spin-coat a flexible optical first film layer on the dried substrate and then perform heat curing; S3. Perform plasma treatment on the flexible optical first film layer to enhance the adhesion between film layers; S4. Spin-coat a flexible optical second film layer on the treated flexible optical first film layer and perform baking curing; S5. Perform plasma treatment or adhesion layer treatment on the flexible optical second film layer to enhance the adhesion between film layers; S6. Perform PECVD deposition of a flexible optical third film layer on the flexible optical second film layer; S7. Package the device.
[0027] In some embodiments, the plasma treatment method in step S3 is: place the flexible optical first film layer in a plasma treatment device and etch it with oxygen at a power of 75 W for 3 minutes.
[0028] In some embodiments, the plasma treatment method in step S5 is: place the flexible optical second film layer in a plasma treatment device; etch it with oxygen at a power of 55 W for 3 minutes.
[0029] The film layer structure of the broadband antireflection film is PDMS / PI / silicon nitride. Among them, both PDMS and PI are extremely good flexible materials. On the basis of refractive index matching, they can provide both a flexible substrate and strength support. Silicon nitride provides a material with a high refractive index to increase the transmittance. In order to implement that silicon nitride has a certain flexible structure while having a high refractive index, and since it is on a flexible substrate, PECVD is selected for deposition. Silane and ammonia are used to generate silicon nitride, which is introduced into the reaction chamber at a ratio of 4:1, and the radio frequency power is controlled at about 300w; the deposition temperature is controlled at about 300 degrees to maintain the stability of the underlying film layer. Silicon nitride is at the top of the film layer and can also act as an electrical insulation layer and a protective layer.
[0030] In some embodiments, a method for preparing a broadband antireflection film for a flexible display panel includes the following steps: S1: First, ultrasonically clean the glass substrate 1 with detergent, deionized water, acetone, and isopropyl alcohol, and then perform a drying treatment; S2: Spin-coat a PDMS solution (by mixing a PDMS preform and a crosslinking agent in a ratio of 10:1, and removing bubbles by vacuum degassing after mixing) on the dried substrate at 2000 rpm; S3: Heat and cure, cure on a hot plate at 60 degrees for 2 hours to ensure the curing of PDMS; S4: Perform plasma treatment on the cured PDMS film layer to enhance the adhesion between film layers; S5: Spin-coat a PI solution (PI is dissolved in an NMP solution) on the treated substrate at a speed of 3000 rpm, and then perform baking and curing, pre-bake at 100 degrees for 30 min, and post-bake at 300 degrees for 1 hour. The solvent is volatilized and cured into a film; S6: Perform plasma treatment on the basis to achieve adhesion between film layers; S7: Use PECVD to deposit on the PI film layer. Silane and ammonia are used to generate silicon nitride, which is introduced into the reaction chamber at a ratio of 4:1, and the radio frequency power is controlled at about 280w. The deposition temperature is controlled at about 300 degrees to maintain the stability of the underlying film layer. Silicon nitride, as the top layer of the film, can also act as an electrical insulation layer and a protective layer.
[0031] S8: Package the device.
[0032] The multilayer antireflection film prepared by the above process has good flexible strength and bendability. We have obtained a multilayer flexible antireflection film structure with good flexible effects and extremely low reflectivity through simulation and specific example tests, and it has good transmittance for common OLED emission light sources incident from the other side.
[0033] The preparation method of the antireflection film based on the multilayer film structure of the present invention is to first ultrasonically clean the glass substrate 1 with detergent, deionized water, acetone, and isopropanol, and then dry the cleaned substrate; then, spin-coat the PDMS solution on the dried substrate at a speed of 2000 rpm. The PDMS solution is formed by mixing a PDMS preform and a cross-linking agent in a ratio of 10:1. After mixing, bubbles are removed by vacuum degassing; then, heat curing is carried out on a hot stage at 60 °C for 2 hours to ensure complete curing of the PDMS layer; then, plasma treatment is carried out on the cured PDMS film layer to enhance the adhesion between the film layers; then, spin-coat the PI solution on the treated substrate at a speed of 3000 rpm. The PI solution is dissolved in the NMP solution. After spin-coating, baking and curing are carried out. The pre-baking lasts for 30 minutes at 100 °C, and the post-baking lasts for 1 hour at 300 °C to volatilize the solvent and cure it into a film; then, plasma treatment is carried out on the cured PI film layer to further enhance the adhesion between the film layers; then, silicon nitride is deposited on the PI film layer by the PECVD method. The silicon nitride is formed by the reaction of silane and ammonia, and the ratio of the reaction gases is 4:1. The radio frequency power is controlled at 280 W, and the deposition temperature is controlled at about 300 °C to ensure the stability of the film layer; the silicon nitride film, as the uppermost film layer, can act as an electrical insulation layer and a protective layer; finally, the device is encapsulated. This multilayer flexible antireflection film has an extremely low reflectivity, can effectively reduce the reflection impact brought by ambient light, and enhance its optical performance. By reasonably designing the film layer structure and its thickness of different materials, and using the refractive index difference of each film layer and the interference effect between the film layers, this antireflection film can achieve the interference cancellation of multiple reflections in a wide wavelength range, thereby greatly reducing the surface reflection. And it is optimized for common OLED optical wavelengths, so that it has a good transmittance for the emitted light of OLEDs.
[0034] In order to verify that the antireflection film obtained by the wide-spectrum antireflection film and its preparation method applied to the flexible AMOELD panel of the present invention has better performance, Example 1 and Comparative Example 1 are provided below to test the wide-spectrum antireflection film obtained by this method.
[0035] Example 1 The film layer structure from bottom to top is as follows: SiO2 / PDMS(107nm) / PI(80nm) / Si3N4(43nm); The preparation method steps are as follows: Step 1: Ultrasonically clean the substrate in turn with detergent, acetone, deionized water, and isopropanol solution; Step 2: Spin-coat the PDMS solution (by mixing PDMS preform and cross-linker in a ratio of 10:1. After mixing, degas under vacuum to remove bubbles) on the dry substrate at 2000 rpm. Heat and cure it on a hot plate at 60 °C for 2 hours to ensure the curing of PDMS. Perform plasma treatment on the cured PDMS film layer to enhance the adhesion between the film layers.
[0036] Step 3: Spin-coat the PI solution (PI dissolved in NMP solution) on the treated substrate at 3000 rpm, and then bake and cure it. Pre-bake at 100 °C for 30 min and post-bake at 300 °C for 1 hour. Evaporate the solvent and make it cure into a film.
[0037] Step 4: Use PECVD for deposition. Use silane and ammonia to generate silicon nitride, and introduce them into the reaction chamber based on a ratio of 4:1. Control the RF power at about 280 w. Control the deposition temperature at about 300 °C to keep the stability of the underlying film layer.
[0038] What is prepared in the above Example 1 is Device 1, that is, Device 1.
[0039] Comparative Example 1 The diode device structure from bottom to top is as follows: SiO2 / Si3N4(151nm) The preparation method steps are as follows: Step 1: Ultrasonically clean the substrate successively with detergent, acetone, deionized water, and isopropyl alcohol solution; Step 2: Deposit silicon nitride on the dry device by using PECVD. Use silane and ammonia to generate silicon nitride, and introduce them into the reaction chamber based on a ratio of 4:1. Control the RF power at about 280 w. Control the deposition temperature at about 300 °C to keep the stability of the underlying film layer.
[0040] What is prepared in the above Comparative Example 1 is Device 2, that is, Device 2.
[0041] As Figure 3 shown, measure the reflection spectra of Example 1 and Comparative Example 1. As can be seen from the figure, the reflectance of the multi-mode layer broadband antireflection film prepared in Example 1 is better than that of Comparative Example 1 in most spectra.
[0042] In summary, the broadband antireflection film provided by the present invention can significantly improve the optical performance of the flexible AMOLED panel, enhance the display effect and reduce the power consumption by optimizing the multi-layer structure and material selection, and has a wide application prospect. The method of the invention is simple and has a wide application range, and can avoid complex doping and post-treatment; compared with the single-layer antireflection film structure, the effect of the multi-layer antireflection film structure is more significant, and the reflectance of the film layer can be significantly reduced; The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.
Claims
1. A wide-spectrum antireflection film for a flexible display panel, characterized in that, It includes a substrate, a first film layer, a second film layer, and a third film layer arranged in sequence from one end to the other end. The first film layer is made of PDMS, the second film layer is made of PI, and the third film layer is made of silicon nitride.
2. The broadband antireflection film for a flexible display panel according to claim 1, wherein The substrate is a glass substrate or an OLED light-emitting module.
3. The broadband antireflection film for a flexible display panel according to claim 1, characterized in that, The thickness of the first film layer is 97 - 117 nm, the thickness of the second film layer is 70 - 90 nm, and the thickness of the third film layer is 33 - 53 nm.
4. The preparation method of a broadband antireflection film for a flexible display panel according to any one of claims 1-3, characterized in that, It includes the following steps: S1. Ultrasonically clean the substrate and perform a drying treatment on the cleaned substrate; S2. Spin-coat the first flexible optical film layer on the dried substrate and then perform heat curing; S3. Perform plasma treatment on the first flexible optical film layer to enhance the adhesion between film layers; S4. Spin-coat the second flexible optical film layer on the treated first flexible optical film layer and perform baking curing; S5. Perform plasma treatment or adhesion layer treatment on the second flexible optical film layer to enhance the adhesion between film layers; S6. Perform PECVD deposition of the third flexible optical film layer on the second flexible optical film layer; S7. Package the device.
5. The preparation method of a wide-spectrum antireflection film for a flexible display panel according to claim 4, characterized in that, The plasma treatment method in step S3 is: Place the first flexible optical film layer in a plasma treatment device and etch it with oxygen at a power of 75 W for 3 minutes.
6. The preparation method of a broadband antireflection film for a flexible display panel according to claim 4, wherein, The plasma treatment method in step S5 is: Place the second flexible optical film layer in a plasma treatment device; etch it with oxygen at a power of 55 W for 3 minutes.