Display panel, preparation method thereof and display device

Abstract

The application provides a display panel, a preparation method thereof and a display device. The display panel comprises a first substrate, a first alignment film and a first flat layer. The first alignment film is arranged on the first substrate. The first flat layer is arranged on a surface of the first alignment film away from the first substrate. The material of the first flat layer comprises liquid crystal and dichroic dye. The first flat layer realizes polarization of light by the liquid crystal and the dichroic dye, thereby removing a polarizer with a multi-film layer structure in the prior art and reducing the thickness of the display panel.

Description

Technical Field

[0001] This invention relates to the field of display devices, and in particular to a display panel, its manufacturing method, and a display device. Background Technology

[0002] TFT-LCD (Thin Film Transistor-Liquid Crystal Display) is one of the mainstream displays currently. However, with the emergence of OLED (Organic Electroluminescence Display), its status in the display industry is gradually diminishing.

[0003] OLEDs do not require backlighting and are self-emissive, making them significantly thinner than LCDs. LCD thinning efforts primarily focus on backlighting, polarizers, and glass. Currently, side-mounted LED backlighting is mainly used, requiring sufficient space for light diffusion to achieve uniform display; therefore, reducing backlight thickness is not easy. Thinning the glass cover also increases the risk of breakage. Therefore, reducing the number of multi-layer polarizers or replacing them with thinner layers would help improve LCD thinning. Summary of the Invention

[0004] The purpose of this invention is to provide a display panel and its manufacturing method and display device, so as to solve the problem that the overall thickness of the display panel is difficult to reduce due to the excessive polarizer film layers and the thick film layers in the existing display panels.

[0005] To achieve the above objectives, the present invention provides a display panel comprising a first substrate, a first alignment film, and a first planarization layer. The first alignment film is disposed on the first substrate. The first planarization layer is disposed on a surface of the first alignment film away from the first substrate. The material of the first planarization layer comprises liquid crystal and dichroic dye.

[0006] Furthermore, the material of the first planarization layer also comprises resin. In the first planarization layer, the total mass percentage of the resin is 60%-80%, the mass percentage of the liquid crystal is 10%-20%, and the mass percentage of the dichroic dye is 10%-20%.

[0007] Furthermore, the resin comprises at least one of epoxy resin and acrylic resin.

[0008] Furthermore, the display panel further includes a liquid crystal layer, a second substrate, a second alignment film, and a second planarization layer. The liquid crystal layer is disposed on a surface of the first planarization layer away from the first substrate. The second substrate is disposed on a surface of the liquid crystal layer away from the first substrate. The second alignment film is disposed on a surface of the second substrate facing the liquid crystal layer. The second planarization layer is disposed on a surface of the second alignment film facing the liquid crystal layer. The material of the second planarization layer is the same as the material of the first planarization layer.

[0009] Furthermore, the display panel also includes a third alignment film and a fourth alignment film. The third alignment film is disposed between the liquid crystal layer and the first planarization layer. The fourth alignment film is disposed between the liquid crystal layer and the second planarization layer.

[0010] Furthermore, the materials of the first alignment film, the second alignment film, the third alignment film, and the fourth alignment film all contain polyimide.

[0011] This invention also provides a method for manufacturing a display panel, the method comprising the following steps:

[0012] A first substrate is provided; a first alignment film is formed on the first substrate; a first planarization layer is formed on a surface of the first alignment film away from the first substrate; wherein the material of the first planarization layer comprises liquid crystal and dichroic dye.

[0013] Furthermore, the step of forming a first planarization layer on a surface of the first alignment film away from the first substrate includes the following steps:

[0014] A resin is prepared in a container, the resin comprising at least one of epoxy resin and acrylic resin; a liquid crystal and a dichroic dye are added to the resin and mixed uniformly to form a planarization coating; wherein, in the planarization coating, the sum of the mass percentages of the resin is 60%-80%, the mass percentage of the liquid crystal is 10%-20%, and the mass percentage of the dichroic dye is 10%-20%; the planarization coating is applied to a surface of the first alignment film away from the first substrate; the planarization coating is cured by a thermosetting process to form the first planarization layer.

[0015] Furthermore, the method for manufacturing the display panel also includes the following steps:

[0016] A second substrate is provided; a second alignment film is formed on the second substrate; a second planarization layer is formed on a surface of the second alignment film away from the second substrate, the material of the second planarization layer being the same as that of the first planarization layer; a third alignment film is formed on the first planarization layer; a fourth alignment film is formed on the second planarization layer; a liquid crystal layer is formed on the third alignment film or the fourth alignment film; and the first substrate and the second substrate are assembled.

[0017] The present invention also provides a display device, which includes a display panel as described above.

[0018] The advantages of this invention are: The display panel and its fabrication method of this invention incorporate liquid crystal and dichroic dyes into the material used to prepare the planarization layer, enabling the planarization layer to possess both leveling and polarization functions. This eliminates the need for multi-layer polarizers in existing technologies, thereby reducing the overall thickness of the display panel. Furthermore, the material for the planarization layer with polarization function is readily available and requires no complex fabrication process. Compared to multi-layer polarizers, this significantly shortens the production time of the display panel and improves production efficiency. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the layered structure of the display panel in Embodiment 1 of the present invention;

[0021] Figure 2 This is a schematic flowchart of the display panel manufacturing method in Embodiment 1 of the present invention;

[0022] Figure 3 This is a schematic diagram of the layered structure of the display panel after step S20 in Embodiment 1 of the present invention;

[0023] Figure 4 This is a schematic diagram of the layered structure of the display panel after step S30 in Embodiment 1 of the present invention;

[0024] Figure 5 This is a schematic diagram of the layered structure of the display panel after step S40 in Embodiment 1 of the present invention;

[0025] Figure 6 This is a schematic diagram of the layered structure of the display panel in Embodiment 2 of the present invention.

[0026] The components in the diagram are shown below:

[0027] Display panel 100; First substrate 10;

[0028] Second substrate 20; Liquid crystal layer 30;

[0029] First leveling layer 40; Second leveling layer 50;

[0030] First alignment film 60; Second alignment film 70;

[0031] Third alignment film 80; Fourth alignment film 90. Detailed Implementation

[0032] The following description, with reference to the accompanying drawings, illustrates preferred embodiments of the present invention, demonstrating its implementability. These embodiments provide a complete overview of the invention for those skilled in the art, making its technical content clearer and easier to understand. The present invention can be embodied in many different forms of embodiments, and the scope of protection of the present invention is not limited to the embodiments mentioned herein.

[0033] In the accompanying drawings, components with the same structure are indicated by the same numerical designation, and components with similar structures or functions are indicated by similar numerical designations. The dimensions and thicknesses of each component shown in the drawings are arbitrary, and the present invention does not limit the dimensions and thicknesses of each component. To make the illustrations clearer, the thickness of components is appropriately exaggerated in some places in the drawings.

[0034] Furthermore, the following descriptions of the embodiments of the invention are made with reference to the accompanying illustrations, illustrating specific embodiments in which the invention can be implemented. Directional terms used in this invention, such as "upper," "lower," "front," "rear," "left," "right," "inner," "outer," and "side," are merely directional references to the accompanying drawings. Therefore, the use of directional terms is for better and clearer explanation and understanding of the invention, and does not indicate or imply that the referred device or element must have a specific orientation, or be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0035] When a component is described as being "on" another component, the component may be placed directly on the other component; alternatively, an intermediate component may exist on which the component is placed, and the intermediate component is placed on the other component. When a component is described as being "installed to" or "connected to" another component, both can be understood as being directly "installed" or "connected" to, or indirectly "installed to" or "connected to" another component via an intermediate component.

[0036] Example 1

[0037] This invention provides a display device, which can be a liquid crystal display device, including a backlight module and a display panel 100. The display panel is used to form a display image. The backlight module is disposed on the back side of the display panel 100 and is used to provide display light to the display panel 100. The display device can be any display device with display function, such as a mobile phone, laptop computer, tablet computer, etc.

[0038] like Figure 1 As shown, the display panel 100 includes a first substrate 10, a liquid crystal layer 30, and a second substrate 20. The first substrate 10, the liquid crystal layer 30, and the second substrate 20 are stacked sequentially.

[0039] The first substrate 10 is an array substrate, which is provided with multiple thin-film transistors and pixel electrodes. The thin-film transistors act as switching devices to control the energization of the pixel electrodes, thereby indirectly controlling the deflection of the liquid crystal molecules in the liquid crystal layer 30 in each pixel unit.

[0040] The liquid crystal layer 30 is disposed on a surface of the first substrate 10 facing the second substrate 20. The liquid crystal layer 30 is filled with a plurality of liquid crystals. When electrical energy is applied to the thin-film transistor, an electric field is generated between the pixel electrode of the first substrate 10 and the common electrode in the second substrate 20. This electric field causes the corresponding liquid crystal molecules in the liquid crystal layer 30 to deflect, thereby allowing backlight light to pass through the liquid crystal layer 30 and form a display image.

[0041] The second substrate 20 is a color filter substrate, located on a surface of the liquid crystal layer 30 away from the first substrate 10. The color filter substrate generally includes a black matrix, a color resist layer, and a common electrode. The second substrate 20 uses the color resist layer to filter and convert uniformly colored display light into different colors, thereby forming a colored display image. The black matrix prevents cross-contamination of light from adjacent pixel units, thus improving the image contrast of the display panel 100. The common electrode cooperates with the pixel electrodes in the first substrate 10 to form an electric field in the liquid crystal layer 30, driving the liquid crystal molecules to deflect.

[0042] The backlight module is generally disposed on a surface of the first substrate 10 away from the liquid crystal layer 30. Light emitted from the backlight module passes through the first substrate 10 and enters the liquid crystal layer 30. Some of the light entering the liquid crystal layer 30 is blocked by the liquid crystal molecules and cannot pass through, while the remaining light passes through the liquid crystal layer 30, thus forming a display image. The light passing through the liquid crystal layer 30 enters the second substrate 20 and is filtered by the color resist layer in the second substrate 20 to form the final color display image.

[0043] Furthermore, the display panel 100 also includes a first planarization layer 40, a second planarization layer 50, a first alignment film 60, and a second alignment film 70.

[0044] Both the first planarization layer 40 and the second planarization layer 50 have polarization functions, and the polarization angles of the first planarization layer 40 and the second planarization layer 50 are perpendicular to each other; for example, the polarization angle of the first planarization layer 40 is 0 degrees and the polarization angle of the second planarization layer 50 is 90 degrees. The first planarization layer 40 is disposed between the first substrate 10 and the liquid crystal layer 30, and it is used to polarize the light passing through the first substrate 10 into polarized light, ensuring that all light entering the liquid crystal layer 30 is polarized light. The second planarization layer 50 is disposed between the second substrate 20 and the liquid crystal layer 30, and it is used to polarize the polarized light passing through the liquid crystal layer 30 into light that is visible to the human eye.

[0045] Specifically, the materials used to prepare the first planarization layer 40 and the second planarization layer 50 include resin materials, liquid crystal, and dichroic dyes. The liquid crystal and the dichroic dye are co-oriented in the first planarization layer 40 and the second planarization layer 50, such that each liquid crystal molecule and each dichroic dye molecule deflects in the same direction. The deflected liquid crystal molecules and dichroic dye molecules only allow light with the same deflection angle to pass through, thereby filtering out polarized light. Furthermore, the deflection directions of the liquid crystal molecules and dichroic dye molecules in the first planarization layer 40 are perpendicular to the deflection directions of the liquid crystal molecules and dichroic dye molecules in the second planarization layer 50, causing the polarization angles of the first planarization layer 40 and the second planarization layer 50 to also be perpendicular to each other.

[0046] The resin material can be propylene glycol methyl ether (PGME), propylene glycol methyl ether acetate (PGMEA), methyl 3-methoxypropionate (MMP), etc., mainly including epoxy resin, acrylic resin, etc. After curing, the organic material has a planarizing effect, ensuring that the surfaces of the first planarization layer 40 and the second planarization layer 50 facing the liquid crystal layer 30 are flat. Simultaneously, after curing, the organic material also fixes the liquid crystal and dichroic dye in the first planarization layer 40 and the second planarization layer 50, preventing the liquid crystal molecules in the first planarization layer 40 and the second planarization layer 50 from changing their deflection angle due to external electric fields, thus ensuring the polarization function of the first planarization layer 40 and the second planarization layer 50.

[0047] Furthermore, the mass ratio of the resin material, the liquid crystal, and the dichroic dye is not fixed and can be adjusted according to the preparation requirements. Specifically, the higher the proportion of the liquid crystal and the dichroic dye, the stronger the polarization capability of the first planarization layer 40 and the second planarization layer 50; the higher the proportion of the organic material, the stronger the leveling capability of the first planarization layer 40 and the second planarization layer 50. Preferably, in the first planarization layer 40 and the second planarization layer 50, the mass percentage of the resin material is 60%-80%, the mass percentage of the liquid crystal is 10%-20%, and the mass percentage of the dichroic dye is 10%-20%.

[0048] The display panel 100 further includes a first alignment film 60, a second alignment film 70, a third alignment film 80, and a fourth alignment film 90.

[0049] The first alignment film 60 is disposed between the first planarization layer 40 and the first substrate 10, and is used to align the randomly arranged liquid crystal molecules and dichroic dye molecules in the first planarization layer 40. The second alignment film 70 is disposed between the second planarization layer 50 and the second substrate 20, and is used to align the randomly arranged liquid crystal molecules and dichroic dye molecules in the second planarization layer 50.

[0050] The third alignment film 80 is disposed on the surface of the liquid crystal layer 30 facing the first substrate 10, and the fourth alignment film 90 is disposed on the surface of the liquid crystal layer 30 facing the second substrate 20. The third alignment film 80 and the fourth alignment film 90 align the randomly arranged liquid crystal molecules in the liquid crystal layer 30 so that the liquid crystal molecules in the liquid crystal layer 30 can rotate normally in the same direction in sequence during operation.

[0051] This invention provides a method for manufacturing a display panel 100, used to manufacture the display panel 100 as described above. The process of the method for manufacturing the display panel 100 is as follows: Figure 2As shown, it includes steps S10-S50.

[0052] Step S10) Provide a first substrate 10 and a second substrate 20: The first substrate 10 and the second substrate 20 can be fabricated by an array substrate process and a color filter substrate process, respectively.

[0053] Step S20) Forming a first alignment film 60 and a second alignment film 70: Polyimide (PI) is coated on the first substrate 10 and the second substrate 20 respectively, and the polyimide coatings on the first substrate 10 and the second substrate 20 are baked and cured. After curing, the polyimide cured layers on the first substrate 10 and the second substrate 20 are rubbed and aligned to form a first alignment film 60 and a second alignment film 70. Figure 3 The first alignment membrane 60 and the second alignment membrane 70 are shown in the figure.

[0054] Step S30) Forming the first planarization layer 40 and the second planarization layer 50: Liquid resin material containing epoxy resin, acrylic resin, etc., is poured into a container; liquid crystal and dichroic dye are added to the container and mixed evenly with the resin material to form a planarization coating. The planarization coating is applied to the surface of the first alignment film away from the first substrate; the planarization coating is uniformly applied to the surface of the first alignment film 60 away from the first substrate 10 and the surface of the second alignment film 70 away from the second substrate 20, respectively, and the planarization coatings on the first alignment film 60 and the second alignment film 70 are thermally cured to form the following layers: Figure 4 The first flattening layer 40 and the second flattening layer 50 are shown in the figure.

[0055] In the planar coating, the resin material accounts for 60%-80% by mass, the liquid crystal accounts for 10%-20% by mass, and the dichroic dye accounts for 10%-20% by mass.

[0056] Step S40) Forming a third alignment film 80 and a fourth alignment film 90: Polyimide is coated on a surface of the first planarization layer 40 away from the first alignment film 60 and a surface of the second planarization layer 50 away from the second alignment film 70, respectively, and the polyimide coatings on the first planarization layer 40 and the second planarization layer 50 are baked and cured. After curing, the cured polyimide layers on the first planarization layer 40 and the second planarization layer 50 are rubbed and aligned to form a third alignment film 80. Figure 5 The third alignment film 80 and the fourth alignment film 90 described herein.

[0057] Step S50) Forming a liquid crystal layer 30 and assembling the cell: A liquid crystal cell is formed on the surface of the third alignment layer away from the first planarization layer 40, and liquid crystal is dropped into the liquid crystal cell to form the liquid crystal layer 30. The surface of the fourth alignment layer away from the second planarization layer 50 is then oriented towards the liquid crystal layer 30, and the first substrate 10 and the second substrate 20 are aligned and bonded together to seal the liquid crystal cell, thus forming a liquid crystal cell. Figure 1 The display panel 100 shown.

[0058] In this embodiment of the invention, liquid crystal and dichroic dye are incorporated into the material used to prepare the planarization layer. This allows the planarization layer to possess both leveling and polarization functions, combining the functions of a polarizer and a planarization layer. This eliminates the need for multi-layer polarizers, reducing the overall thickness of the display panel and achieving ultra-thin liquid crystal displays, thus enhancing the competitiveness of the liquid crystal panel. Furthermore, the material for the planarization layer with polarization function is readily available and requires no complex manufacturing process. Compared to multi-layer polarizers, this significantly shortens the production time of the display panel and improves production efficiency.

[0059] Furthermore, in other embodiments of the present invention, a liquid crystal layer can be formed on the fourth alignment film, and then the surface of the third alignment film away from the first planarization layer can be aligned and bonded to the liquid crystal layer. This is similar to the preparation method of preparing the liquid crystal layer on the third alignment film in this embodiment, and therefore will not be described in detail here. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0060] Example 2

[0061] This invention provides a display device, which can be an OLED (Organic Light-Emitting Diode), Mini-LED (Mini Light-Emitting Diode), or Micro-LED (Micro Light-Emitting Diode) display device. The display device can be any display device with display functionality, such as a mobile phone, laptop computer, or tablet computer.

[0062] like Figure 6 As shown, the display panel 100 includes a first substrate 10, a first planarization layer 40, and a first alignment film 60.

[0063] The first substrate 10 is an array substrate, which has multiple thin-film transistors, pixel electrodes, and multiple light-emitting devices. The thin-film transistors act as switching devices to control the energization of the pixel electrodes. The light-emitting devices are electrically connected to the thin-film transistors through the pixel electrodes. The light-emitting devices can be self-emissive devices such as OLEDs, Mini-LEDs, or Micro-LEDs, and their emission is controlled by turning the thin-film transistors on or off, thereby realizing the display of the image.

[0064] The first planarization layer 40 is disposed on the light-emitting surface of the first substrate 10. The first planarization layer 40 has a polarization function, which is used to shield ambient light. Specifically, the materials used to fabricate the first planarization layer 40 include organic materials, liquid crystal, and dichroic dyes.

[0065] The liquid crystal and the dichroic dye are co-oriented in the first planarization layer 40 and the second planarization layer 50, so that each liquid crystal molecule and each dichroic dye molecule are deflected in the same direction. The deflected liquid crystal molecules and dichroic dye molecules only allow light with the same deflection angle to pass through, so that the display light can pass through the first planarization layer 40, while the ambient light cannot pass through the first planarization layer 40.

[0066] The organic material can be propylene glycol methyl ether (PGME), propylene glycol methyl ether acetate (PGMEA), methyl 3-methoxypropionate (MMP), etc., and mainly includes epoxy resin, acrylic resin, etc. After curing, the organic material has a planarizing effect, ensuring a smooth surface of the first planarization layer 40. Simultaneously, after curing, the organic material also fixes the liquid crystal and dichroic dye in the first planarization layer 40, preventing the liquid crystal molecules in the first planarization layer 40 from changing their deflection angle due to external electric fields, thus ensuring the polarization function of the first planarization layer 40.

[0067] Furthermore, the mass ratio of the organic material, the liquid crystal, and the dichroic dye is not fixed and can be adjusted according to the preparation requirements. Specifically, the higher the proportion of the liquid crystal and the dichroic dye, the stronger the polarization capability of the first planarization layer 40; the higher the proportion of the organic material, the stronger the leveling capability of the first planarization layer 40. Preferably, in the first planarization layer 40, the mass percentage of the organic material is 60%-80%, the mass percentage of the liquid crystal is 10%-20%, and the mass percentage of the dichroic dye is 10%-20%.

[0068] The first alignment film 60 is disposed between the first planarization layer 40 and the first substrate 10, and is used to arrange the randomly arranged liquid crystal molecules and dichroic dye molecules in the first planarization layer 40 into a neat arrangement.

[0069] In this embodiment of the invention, liquid crystal and dichroic dye are incorporated into the material used to prepare the planarization layer, so that the planarization layer has both leveling and polarization functions. This combines the functions of polarizers in the prior art with those of the planarization layer, thereby eliminating the need for multi-layer polarizers, reducing the overall thickness of the display panel, and further achieving ultra-thin displays.

[0070] While the invention has been described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that different dependent claims and features described herein can be combined in ways different from those described in the original claims. It is also understood that features described in conjunction with individual embodiments can be used in other described embodiments.

Claims

1. A display panel, characterized in that, include: First substrate; A first alignment film is disposed on the first substrate; A first planarization layer is disposed on a surface of the first alignment film away from the first substrate; The material of the first planarization layer includes resin, liquid crystal and dichroic dye; The material of the first alignment film contains polyimide.

2. The display panel as described in claim 1, characterized in that, In the first planarization layer, the resin has a mass percentage of 60%-80%, the liquid crystal has a mass percentage of 10%-20%, and the dichroic dye has a mass percentage of 10%-20%.

3. The display panel as described in claim 2, characterized in that, The resin comprises at least one of epoxy resin and acrylic resin.

4. The display panel as described in claim 1, characterized in that, Also includes: A liquid crystal layer is disposed on a surface of the first planarization layer that is away from the first substrate; The second substrate is disposed on a surface of the liquid crystal layer away from the first substrate; A second alignment film is disposed on a surface of the second substrate facing the liquid crystal layer; The second planarization layer is disposed on a surface of the second alignment film facing the liquid crystal layer; The material of the second planarization layer is the same as that of the first planarization layer.

5. The display panel as described in claim 4, characterized in that, Also includes: A third alignment film is disposed between the liquid crystal layer and the first planarization layer; A fourth alignment film is disposed between the liquid crystal layer and the second planarization layer.

6. The display panel as described in claim 5, characterized in that, The materials of the second alignment film, the third alignment film, and the fourth alignment film all contain polyimide.

7. A method for manufacturing a display panel, characterized in that, Includes the following steps: Provide a first substrate; A first alignment film is formed on the first substrate, wherein the material of the first alignment film comprises polyimide; A first planarization layer is formed on a surface of the first alignment film away from the first substrate; The material of the first planarization layer includes resin, liquid crystal and dichroic dye.

8. The method for manufacturing a display panel as described in claim 7, characterized in that, The step of forming a first planarization layer on a surface of the first alignment film away from the first substrate includes the following steps: The resin is prepared in a container, the resin comprising at least one of epoxy resin and acrylic resin; Liquid crystal and dichroic dye are added to the resin and mixed evenly to form a planar coating; wherein, in the planar coating, the total mass percentage of the resin is 60%-80%, the mass percentage of the liquid crystal is 10%-20%, and the mass percentage of the dichroic dye is 10%-20%. The planar coating is applied to a surface of the first alignment film away from the first substrate; The planarizing coating is cured by a thermosetting process to form the first planarization layer.

9. The method for manufacturing a display panel as described in claim 7, characterized in that, It also includes the following steps: Provide a second substrate; A second alignment film is formed on the second substrate; A second planarization layer is formed on a surface of the second alignment film away from the second substrate, and the material of the second planarization layer is the same as that of the first planarization layer. A third alignment film is formed on the first planarization layer; A fourth alignment film is formed on the second planarization layer; A liquid crystal layer is formed on the third alignment film or the fourth alignment film; Assemble the first substrate and the second substrate.

10. A display device, characterized in that, Includes the display panel as described in any one of claims 1-6.

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