Display panel, color film substrate and method for preparing color film substrate

Abstract

The present application provides a display panel, a color filter substrate and a method for preparing a color filter substrate, wherein the color filter substrate includes a plurality of photoresist units, each of which includes a first photoresist block, a second photoresist block and a third photoresist block, and a light shielding layer is arranged between two adjacent photoresist blocks, and the light shielding layer includes a first sub-light shielding layer, a second sub-light shielding layer and a third sub-light shielding layer arranged in a stacked manner; wherein the first photoresist block and the first sub-light shielding layer are formed by patterning the first photoresist layer, the second photoresist block and the second sub-light shielding layer are formed by patterning the second photoresist layer, the third photoresist block and the third sub-light shielding layer are formed by patterning the third photoresist layer, and the colors of the first photoresist layer, the second photoresist layer and the third photoresist layer are different, and two of them are positive photoresist layers, and the other is a negative photoresist layer. The structural design of the above-mentioned color filter substrate can be formed using only two mask plates, thereby simplifying the preparation process of the color filter substrate and saving costs.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a display panel, a color film substrate, and a method for preparing the color film substrate. Background Art

[0002] Polarizer (POL) can effectively reduce the reflectivity of the display panel under strong light, but it loses nearly 58% of the light output. This greatly increases the life span of the display panel; on the other hand, the polarizer is thick and brittle, which is not conducive to the development of dynamic bending products. The use of color filter substrate (Color Filter, CF for short) to replace polarizer is classified as POL-less (de-polarizer technology). The basic principle of Pol-less technology is to use a color filter film instead of a polarizer to improve the reflection effect. Its working principle is simple: only light of the same color as the pixel can pass through, and other light (including incident light and reflected light) will be absorbed by the black shading layer.

[0003] POL-less (de-polarizer technology) is currently a new technology that panel manufacturers are vigorously developing. CF replaces POL, making the panel thinner and more conducive to application in folding displays. The problem is that using CF means more masks are needed, and mask equipment is one of the most expensive tools in panel manufacturing, which will bring huge capital expenditures to manufacturers. Summary of the invention

[0004] The present application provides a display panel, a color film substrate and a method for preparing the color film substrate, which can solve the problem of many masks required for the preparation of the existing color film substrate.

[0005] In order to solve the above technical problems, the first technical solution provided by the present application is: to provide a color film substrate, the color film substrate includes multiple photoresist units, each light resist unit includes a first light resist block, a second light resist block, and a third light resist block, and a light shielding layer is arranged between two adjacent light resist blocks, and the light shielding layer includes a first sub-light shielding layer, a second sub-light shielding layer and a third sub-light shielding layer that are stacked; wherein, the first light resist block and the first sub-light shielding layer are formed by patterning the first photoresist layer, the second light resist block and the second sub-light shielding layer are formed by patterning the second photoresist layer, the third light resist block and the third sub-light shielding layer are formed by patterning the third photoresist layer, the colors of the first photoresist layer, the second light resist layer and the third photoresist layer are different, and two of them are positive photoresist layers, and the other is a negative photoresist layer.

[0006] In one embodiment, the thickness of the first photoresist block, the second photoresist block and the third photoresist block ranges from 1.5 to 6 microns, and the thickness of the first sub-light-shielding layer, the second sub-light-shielding layer and the third sub-light-shielding layer ranges from 0.5 to 4 microns.

[0007] In one embodiment, the thickness of the first light block, the second light block and the third light block are the same; the thickness of the first sub-light-shielding layer, the second sub-light-shielding layer and the third sub-light-shielding layer are the same; and the thickness of the light-shielding layer is greater than the thickness of the first light block, the second light block and the third light block.

[0008] In one embodiment, the first light block has the same color as the first sub-light-shielding layer, the second light block has the same color as the second sub-light-shielding layer, the third light block has the same color as the third sub-light-shielding layer, and the first light block, the second light block and the third light block respectively include one of red, green and blue.

[0009] To solve the above technical problems, the second technical solution provided in the present application is: providing a display panel, comprising: an array substrate; a color film substrate, arranged relatively to one side of the array substrate, and the color film substrate is the color film substrate described in any one of the above items.

[0010] In order to solve the above technical problems, the third technical solution provided by the present application is: to provide a method for preparing a color filter substrate, comprising: providing a substrate, the substrate comprising a first light block corresponding area, a second light block corresponding area, a third light block corresponding area, and a shading corresponding area located between adjacent light block corresponding areas; coating a first photoresist layer on the substrate and patterning it; the patterned first photoresist layer comprises a first light block located on the first light block corresponding area and a first sub-light-shielding layer located on the shading corresponding area; coating a second photoresist layer on a surface of the first photoresist layer away from the substrate and patterning it; the patterned second photoresist layer comprises a second light block located on the second light block corresponding area and a second sub-light-shielding layer located on the shading corresponding area; A third photoresist layer is coated on the surface of the second photoresist layer facing away from the substrate and patterned; the patterned third photoresist layer includes a third photoresist block located on the corresponding area of ​​the third photoresist block and a third sub-light-shielding layer located on the corresponding area of ​​the light-shielding; and the first sub-light-shielding layer, the second sub-light-shielding layer and the third sub-light-shielding layer on the corresponding area of ​​the light-shielding are stacked to form a light-shielding layer; wherein the first photoresist layer, the second photoresist layer and the third photoresist layer have different colors, and two of them are positive photoresist layers, and the other is a negative photoresist layer; the patterning of the two positive photoresist layers is completed by using a first mask and a second mask respectively, and the patterning of the negative photoresist layer is completed by using the first mask and the second mask which are stacked.

[0011] In one embodiment, the first mask and the second mask both include a first light-transmitting area with a light transmittance of 0%, a second light-transmitting area with a light transmittance of 100%, and a third light-transmitting area with a light transmittance range of 33-67%; the two photoresist blocks formed by the two positive photoresist layers are respectively arranged corresponding to the first light-transmitting areas of the first mask and the second mask, and the two sub-light-shielding layers formed by the two positive photoresist layers are arranged corresponding to the third light-transmitting areas of the first mask and the second mask; the first mask and the second mask are stacked to form a composite mask, and the composite mask includes a fourth light-transmitting area with a light transmittance of 0%, a fifth light-transmitting area with a light transmittance of 100%, and a sixth light-transmitting area with a light transmittance range of 33-67%; the photoresist blocks formed by the negative photoresist layer are arranged corresponding to the fifth light-transmitting area of ​​the composite mask, and the sub-light-shielding layers formed by the negative photoresist layer are arranged corresponding to the sixth light-transmitting area of ​​the composite mask.

[0012] In one embodiment, the light transmittance of the third light-transmitting area is 50%, the sixth light-transmitting area is formed by stacking the third light-transmitting area of ​​the first mask and the third light-transmitting area of ​​the second mask, and the light transmittance of the sixth light-transmitting area is 50%.

[0013] In one embodiment, the first photoresist layer is a negative photoresist layer; or, the second photoresist layer is a negative photoresist layer; or, the third photoresist layer is a negative photoresist layer.

[0014] In one embodiment, the colors of the first photoresist layer, the second photoresist layer and the third photoresist layer include one of red, green and blue respectively.

[0015] Different from the prior art, the beneficial effect of the present application lies in that the first photoresist block and the first sub-light-shielding layer are formed by patterning the first photoresist layer, the second photoresist block and the second sub-light-shielding layer are formed by patterning the second photoresist layer, the third photoresist block and the third sub-light-shielding layer are formed by patterning the third photoresist layer, and two of the first photoresist layer, the second photoresist layer and the third photoresist layer are positive photoresist layers, and the other is a negative photoresist layer. Through the above design, when preparing the color filter substrate, the mask plates used for patterning the two positive photoresist layers can be stacked to pattern the negative photoresist layer, so that the color filter substrate can be formed using only two mask plates, thereby simplifying the preparation process of the color filter substrate and saving costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work, among which:

[0017] Figure 1 A partial cross-sectional view of an embodiment of a color filter substrate provided by the present application;

[0018] Figure 2 A partial cross-sectional view of another embodiment of the color filter substrate provided by the present application;

[0019] Figure 3 A schematic diagram of a process of an embodiment of a method for preparing a color filter substrate provided in the present application;

[0020] Figure 4 A schematic diagram of depositing a first photoresist layer on a substrate and patterning the first photoresist layer using a first mask;

[0021] Figure 5 is a schematic diagram of patterning the first photoresist layer using the first mask;

[0022] Figure 6 A schematic diagram of depositing a second photoresist layer on the patterned first photoresist layer and patterning the second photoresist layer using a second mask;

[0023] Figure 7 is a schematic diagram of patterning the second photoresist layer using a second mask;

[0024] Figure 8 A schematic diagram of depositing a third photoresist layer on the patterned second photoresist layer and patterning the third photoresist layer using a composite mask;

[0025] Fig. 9 is a schematic diagram of patterning the third photoresist layer using a composite mask;

[0026] Fig.10 A schematic structural diagram of an embodiment of a display panel provided in the present application. DETAILED DESCRIPTION

[0027] The terms "first", "second" and "third" in this application are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined as "first", "second" and "third" can explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. All directional indications in the embodiments of the present application (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication also changes accordingly. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions.

[0028] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0029] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0030] Existing color filter substrates generally include a color filter layer and a light-shielding layer. The color filter layer can be composed of multiple red photoresist blocks, multiple green photoresist blocks, multiple blue photoresist blocks, multiple white photoresist blocks, etc. The light-shielding layer is arranged between adjacent color blocks, and only light of the same color as the photoresist blocks can pass through, and other light (including incident light and reflected light) will be absorbed by the black light-shielding layer. Although the display effect is better when using a color filter substrate instead of a polarizer, it also greatly increases the complexity and cost of the display panel manufacturing process. If the color filter substrate is prepared by photolithography, it is estimated that at least four to five masks (masks) are required. The mask equipment is one of the most expensive tools in display panel manufacturing, which will bring huge capital expenditures to manufacturers.

[0031] To reduce the preparation cost of color film substrate, see Figure 1 and Figure 2 , Figure 1 A partial cross-sectional view of an embodiment of a color filter substrate provided by the present application; Figure 2A partial cross-sectional view of another embodiment of the color filter substrate provided by the present application. Specifically, the color filter substrate 100 provided by the present application can be prepared using only two masks, compared to the existing color filter substrates which require four to five masks to prepare, thereby simplifying the process and reducing costs.

[0032] Specifically, the color film substrate 100 provided in the present application includes a plurality of light blocking units 10, each light blocking unit 10 includes a first light blocking block 11, a second light blocking block 12, and a third light blocking block 13, and a light shading layer 20 is arranged between two adjacent light blocking blocks, and the light shading layer 20 includes a first sub-light shading layer 21, a second sub-light shading layer 22, and a third sub-light shading layer 23 which are stacked.

[0033] Among them, Figures 4 to 9 As shown, the first photoresist block 11 and the first sub-light-shielding layer 21 are formed by patterning the first photoresist layer 1, the second photoresist block 12 and the second sub-light-shielding layer 22 are formed by patterning the second photoresist layer 2, and the third photoresist block 13 and the third sub-light-shielding layer 23 are formed by patterning the third photoresist layer 3; the first photoresist layer 1, the second photoresist layer 2 and the third photoresist layer 3 have different colors, and two of them are positive photoresist layers, and the other is a negative photoresist layer.

[0034] The patterning methods include but are not limited to exposure and development, and other existing patterning processes.

[0035] It can be understood that since the first photoresist block 11 and the first sub-light-shielding layer 21 are formed by patterning the first photoresist layer 1, the color of the first photoresist block 11 and the first sub-light-shielding layer 21 is the same as the color of the first photoresist layer 1; since the second photoresist block 12 and the second sub-light-shielding layer 22 are formed by patterning the second photoresist layer 2, the color of the second photoresist block 12 and the second sub-light-shielding layer 22 is the same as the color of the second photoresist layer 2; since the third photoresist block 13 and the third sub-light-shielding layer 23 are formed by patterning the third photoresist layer 3, the color of the third photoresist block 13 and the third sub-light-shielding layer 23 is the same as the color of the third photoresist layer 3.

[0036] The colors of the first photoresist layer 1, the second photoresist layer 2 and the third photoresist layer 3 include but are not limited to any three of red, green, blue and white. In some embodiments of the present application, the first photoresist layer 1 is a red photoresist layer, the second photoresist layer 2 is a green photoresist layer, and the third photoresist layer 3 is a blue photoresist layer; or, the first photoresist layer 1 is a red photoresist layer, the second photoresist layer 2 is a blue photoresist layer, and the third photoresist layer 3 is a green photoresist layer; or, the first photoresist layer 1 is a green photoresist layer, the second photoresist layer 2 is a blue photoresist layer, and the third photoresist layer 3 is a red photoresist layer, etc., which are not limited here and can be selected according to actual needs.

[0037] For ease of description, the present application embodiment is described by taking the first photoresist layer 1 as a red photoresist layer, the second photoresist layer 2 as a green photoresist layer, and the third photoresist layer 3 as a blue photoresist layer as an example. That is, the first photoresist block 11 and the first sub-light-shielding layer 21 have the same color and are red, the second photoresist block 12 and the second sub-light-shielding layer 22 have the same color and are green, and the third photoresist block 13 and the third sub-light-shielding layer 23 have the same color and are blue.

[0038] In addition, two of the first photoresist layer 1, the second photoresist layer 2 and the third photoresist layer 3 are positive photoresist layers, and the other is a negative photoresist layer. The first photoresist layer 1 may be a negative photoresist layer, and the second photoresist layer 2 and the third photoresist layer 3 may be positive photoresist layers; or, the first photoresist layer 1 and the second photoresist layer 2 may be positive photoresist layers, and the third photoresist layer 3 may be negative photoresist layers; or, the first photoresist layer 1 and the third photoresist layer 3 may be positive photoresist layers, and the second photoresist layer 2 may be a negative photoresist layer. The specific design is based on actual needs and is not limited here.

[0039] Specifically, the present application designs two of the first photoresist layer 1, the second photoresist layer 2 and the third photoresist layer 3 as positive photoresist layers and the other as a negative photoresist layer, so that when preparing the color filter substrate 100, the mask plates used for patterning the two positive photoresist layers can be stacked to pattern the negative photoresist layer. Therefore, the color filter substrate 100 can be formed using only two mask plates, thereby simplifying the preparation process of the color filter substrate 100 and saving costs.

[0040] In some embodiments, Figure 1 As shown, the first light blocking block 11, the second light blocking block 12 and the third light blocking block 13 have the same thickness; the first sub-light blocking layer 21, the second sub-light blocking layer 22 and the third sub-light blocking layer 23 have the same thickness.

[0041] Specifically, the first light block 11, the second light block 12, and the third light block 13 have the same thickness, that is, the thickness of each light block in each light blocking unit 10 is the same, so as to ensure the uniformity of light emission of the display panel using the color filter substrate 100. It can be understood that, for example, if the thickness of the first light block 11 is relatively thick, and the thickness of the third light block 13 is relatively thin, it may cause the angle and time of the light emitted from the first light block 11 and the light emitted from the third light block 13 to be different, thereby causing the display panel using the color filter substrate 100 to have a display unevenness problem.

[0042] The thickness of the first sub-light shielding layer 21, the second sub-light shielding layer 22 and the third sub-light shielding layer 23 are the same, that is, each sub-light shielding layer in each light shielding layer 20 has the same absorption effect on the outgoing light and incident light of other colors, which is conducive to dividing adjacent light blocking blocks, blocking the gaps of colors, and preventing light blocking blocks from leaking light or mixing colors. It can be understood that, for example, if the thickness of the first sub-light shielding layer 21 is too thin compared to the sub-light shielding layers 21 of the other two colors, the first sub-light shielding layer 21 has a weaker blocking effect on green light and blue light, which may cause the first sub-light shielding layer 21 to be unable to effectively block the emission of green light and blue light, thereby causing light leakage in the light shielding layer 20 and mixing of colors of adjacent light blocking blocks of different colors.

[0043] In other embodiments, the thickness of the first light blocking block 11, the second light blocking block 12 and the third light blocking block 13 may be the same; the thickness of the first sub-light blocking layer 21, the second sub-light blocking layer 22 and the third sub-light blocking layer 23 may be different or different. The thinnest thickness of the first sub-light blocking layer 21, the second sub-light blocking layer 22 and the third sub-light blocking layer 23 needs to ensure that the optical density (OD) value can effectively absorb the emitted light of other colors.

[0044] Please continue to see Figure 2 , the thickness of the first light-blocking block 11, the second light-blocking block 12 and the third light-blocking block 13 are the same; the thickness of the second sub-light-shielding layer 22 and the third sub-light-shielding layer 23 are the same and are less than the thickness of the first sub-light-shielding layer 21. Among them, the thickness of the first sub-light-shielding layer 21 needs to ensure that the optical density (OD) value can effectively absorb the green and blue emitted light, the thickness of the second sub-light-shielding layer 22 needs to ensure that the optical density (OD) value can effectively absorb the red and blue emitted light, and the thickness of the third sub-light-shielding layer 23 needs to ensure that the optical density (OD) value can effectively absorb the red and green emitted light.

[0045] In addition, since the present application uses two mask plates for positive photoresist layers to be stacked to pattern the negative photoresist layer, the thickness of the shading layer 20 formed by the stacking of the first sub-light-shielding layer 21, the second sub-light-shielding layer 22 and the third sub-light-shielding layer 23 is greater than the thickness of the first photoresist block, the second photoresist block and the third photoresist block.

[0046] In some embodiments, the thickness of the first photoblock 11, the second photoblock 12, and the third photoblock 13 ranges from 1.5 to 6 micrometers. For example, the thickness of the first photoblock 11, the second photoblock 12, and the third photoblock 13 may all be 1.5 micrometers, 3 micrometers, 4.5 micrometers, or 6 micrometers, etc., which are not limited here.

[0047] In some embodiments, the thickness of the first sub-light shielding layer 21, the second sub-light shielding layer 22, and the third sub-light shielding layer 23 ranges from 0.5 to 4 microns. For example, the thickness of the first sub-light shielding layer 21, the second sub-light shielding layer 22, and the third sub-light shielding layer 23 can all be 0.5 microns, 1 micron, 2 microns, 3 microns, or 4 microns, etc., which are not limited here. Figure 2 In the color filter substrate 100 shown, the thicknesses of the first sub-light-shielding layer 21, the second sub-light-shielding layer 22 and the third sub-light-shielding layer 23 can be different, as long as the optical density (OD) value of the thinnest thickness of each sub-light-shielding layer can effectively absorb the emitted light of other colors.

[0048] In some embodiments, the color filter substrate 100 further includes a substrate 30, which is used to carry a plurality of light blocking units 10 and a light shielding layer 20. The material of the substrate 30 may include but is not limited to a glass substrate 30, transparent ITO (indium tin oxide), and the like.

[0049] Different from the prior art, the beneficial effect of the color filter substrate 100 provided in the present application lies in that, by designing two of the first photoresist layer 1, the second photoresist layer 2 and the third photoresist layer 3 to be positive photoresist layers and the other one to be a negative photoresist layer, when preparing the color filter substrate 100, the mask plates used for patterning the two positive photoresist layers can be stacked to pattern the negative photoresist layer, so that the color filter substrate 100 can be formed using only two mask plates, thereby simplifying the preparation process of the color filter substrate 100 and saving costs.

[0050] See also Figure 3-Figure 9 , Figure 3 A schematic diagram of a process of an embodiment of a method for preparing a color filter substrate provided in the present application; Figure 4 A schematic diagram of depositing a first photoresist layer on a substrate and patterning the first photoresist layer using a first mask; Figure 5 is a schematic diagram of patterning the first photoresist layer using the first mask; Figure 6 A schematic diagram of depositing a second photoresist layer on the patterned first photoresist layer and patterning the second photoresist layer using a second mask; Figure 7 is a schematic diagram of patterning the second photoresist layer using a second mask; Figure 8 A schematic diagram of depositing a third photoresist layer on the patterned second photoresist layer and patterning the third photoresist layer using a composite mask; Fig. 9 It is a schematic diagram after patterning the third photoresist layer using a composite mask.

[0051] Specifically, the present application also provides a method for preparing a color filter substrate 100, comprising:

[0052] Step S1: providing a substrate 30 , the substrate 30 comprising a first light block corresponding area A1 , a second light block corresponding area A2 , a third light block corresponding area A3 , and a light shielding corresponding area A4 located between adjacent light block corresponding areas.

[0053] In some embodiments, the material of the substrate 30 includes but is not limited to a glass substrate 30 , transparent ITO (indium tin oxide), and the like.

[0054] In some embodiments, the number of the first photoblock corresponding area A1, the second photoblock corresponding area A2, the third photoblock corresponding area A3, and the shading corresponding area A4 are multiple and arranged in an array, and an adjacent first photoblock corresponding area A1, a second photoblock corresponding area A2, and a third photoblock corresponding area A3 form a photoblock unit corresponding area.

[0055] Step S2: coating a first photoresist layer 1 on the substrate 30 and patterning it; the patterned first photoresist layer 1 includes a first photoresist block located on the first photoresist block corresponding area A1 and a first sub-light shielding layer 21 located on the light shielding corresponding area A4.

[0056] Among them, Figure 4 The first photoresist layer 1 shown is a positive photoresist layer. Figure 4 The first mask B1 shown includes a first light-transmitting area C1 with a light transmittance of 0%, a second light-transmitting area C2 with a light transmittance of 100%, and a third light-transmitting area C3 with a light transmittance range of 50%. The first light-transmitting area C1 is arranged corresponding to the first photoresist block corresponding area A1, the second light-transmitting area C2 is arranged corresponding to the second photoresist block corresponding area A2 and the third photoresist block corresponding area A3, and the third light-transmitting area C3 is arranged corresponding to the light-shielding corresponding area A4.

[0057] Combination Figure 4 and Figure 5 The patterning of the first photoresist layer 1 is completed by the first mask B1. Specifically, the first photoresist layer 1 is patterned by the first mask B1 to form a patterned first photoresist layer 1. The patterned first photoresist layer 1 includes a first photoresist block located on the first photoresist block corresponding area A1 and a first sub-shielding layer 21 located on the shading corresponding area A4.

[0058] In the present application, patterning methods include but are not limited to exposure and development, and other existing patterning processes.

[0059] It can be understood that since the first photoresist layer 1 is a positive photoresist layer, after patterning by the first mask B1, the area with a light transmittance of 0% on the corresponding first mask B1 is completely retained, that is, the first photoresist layer 1 on the corresponding area A1 of the first photoresist block is completely retained to form the first photoresist block; the area with a light transmittance of 100% on the corresponding first mask B1 is completely etched, that is, the first photoresist layer 1 on the corresponding area A2 of the second photoresist block and the corresponding area A3 of the third photoresist block is completely etched; the area with a light transmittance of 50% on the corresponding first mask B1 is retained at half the thickness, that is, the first photoresist layer 1 on the shading corresponding area A4 is retained at half the thickness to form the first sub-light-shielding layer 21.

[0060] Step S3: coating a second photoresist layer 2 on the surface of the first photoresist layer 1 facing away from the substrate 30 and patterning it; the patterned second photoresist layer 2 includes a second photoresist block located on the second photoresist block corresponding area A2 and a second sub-shielding layer 22 located on the shading corresponding area A4.

[0061] It should be noted that the second photoresist layer 2 is coated on the surface of the first photoresist layer 1 facing away from the substrate 30 , specifically, the second photoresist layer 2 is coated on the surface of the patterned first photoresist layer 1 facing away from the substrate 30 .

[0062] Among them, Figure 6 The second photoresist layer 2 shown is a positive photoresist layer, and its thickness is the same as that of the first photoresist layer 1. Figure 6 The second mask B2 shown includes a first light-transmitting area C1 with a light transmittance of 0%, a second light-transmitting area C2 with a light transmittance of 100%, and a third light-transmitting area C3 with a light transmittance range of 50%. The first light-transmitting area C1 is arranged corresponding to the second photoresist block corresponding area A2, the second light-transmitting area C2 is arranged corresponding to the first photoresist block corresponding area A1 and the third photoresist block corresponding area A3, and the third light-transmitting area C3 is arranged corresponding to the light-shielding corresponding area A4.

[0063] Combination Figure 6 and Figure 7 The patterning of the second photoresist layer 2 is completed by the second mask B2. Specifically, the second photoresist layer 2 is patterned using the second mask B2 to form a patterned second photoresist layer 2. The patterned second photoresist layer 2 includes a second photoresist block located on the second photoresist block corresponding area A2 and a second sub-light-shielding layer 22 located on the light-shielding corresponding area A4.

[0064] It can be understood that since the second photoresist layer 2 is a positive photoresist layer, after patterning by the second mask B2, the area with a light transmittance of 0% on the corresponding second mask B2 is completely retained, that is, the second photoresist layer 2 on the corresponding area A2 of the second photoresist block is completely retained to form a second photoresist block; the area with a light transmittance of 100% on the corresponding second mask B2 is completely etched, that is, the second photoresist layer 2 on the corresponding area A1 of the first photoresist block and the corresponding area A3 of the third photoresist block is completely etched; the area with a light transmittance of 50% on the corresponding second mask B2 is retained at half the thickness, that is, the second photoresist layer 2 on the shading corresponding area A4 is retained at half the thickness to form a second sub-light-shielding layer 22.

[0065] Step S4: coating a third photoresist layer 3 on the surface of the second photoresist layer 2 facing away from the substrate 30 and patterning it; the patterned third photoresist layer 3 includes a third photoresist block located on the third photoresist block corresponding area A3 and a third sub-light-shielding layer 23 located on the light-shielding corresponding area A4; and stacking the first sub-light-shielding layer 21, the second sub-light-shielding layer 22 and the third sub-light-shielding layer 23 on the light-shielding corresponding area A4 to form a light-shielding layer 20.

[0066] It should be noted that the third photoresist layer 3 is coated on the surface of the second photoresist layer 2 facing away from the substrate 30 , specifically, the third photoresist layer 3 is coated on the surface of the patterned second photoresist layer 2 facing away from the substrate 30 .

[0067] Among them, Figure 8 The third photoresist layer 3 shown is a negative photoresist layer, and has the same thickness as the first photoresist layer 1 and the second photoresist layer 2. Figure 8 As shown, the first mask B1 and the second mask B2 are stacked to form a composite mask B to pattern the third photoresist layer 3, and the composite mask B includes a fourth light-transmitting area C4 with a light transmittance of 0%, a fifth light-transmitting area C5 with a light transmittance of 100%, and a third light-transmitting area C3 with a light transmittance range of 50%. Among them, the fourth light-transmitting area C4 is set corresponding to the first photoresist block corresponding area A1 and the second photoresist block corresponding area A2, the fifth light-transmitting area C5 is set corresponding to the third photoresist block corresponding area A3, and the sixth light-transmitting area C6 is set corresponding to the light-shielding corresponding area A4.

[0068] Combination Figure 8 and Fig. 9 The patterning of the third photoresist layer 3 is completed by the composite mask B. Specifically, the third photoresist layer 3 is patterned by the composite mask B to form a patterned third photoresist layer 3. The patterned third photoresist layer 3 includes a third photoresist block located on the third photoresist block corresponding area A3 and a third sub-light-shielding layer 23 located on the light-shielding corresponding area A4.

[0069] It can be understood that, since the third photoresist layer 3 is a negative photoresist layer, after patterning of the composite mask B, the area corresponding to the composite mask B with a light transmittance of 0% is completely etched, that is, the third photoresist layer 3 on the first photoresist block corresponding area A1 and the second photoresist block corresponding area A2 is completely etched; the area corresponding to the composite mask B with a light transmittance of 100% is completely reserved, that is, the third photoresist layer 3 on the third photoresist block corresponding area A3 is completely reserved to form a third photoresist block; the area corresponding to the composite mask B with a light transmittance of 50% is reserved with half the thickness, that is, the third photoresist layer 3 on the light shielding corresponding area A4 is reserved with half the thickness to form a third sub-light shielding layer 23. And the first sub-light shielding layer 21, the second sub-light shielding layer 22 and the third sub-light shielding layer 23 on the light shielding corresponding area A4 are stacked to form a light shielding layer 20.

[0070] Among them, Figures 4 to 9 In the color filter substrate 100 prepared by the preparation method shown, the first photoresist layer 1, the second photoresist layer 2 and the third photoresist layer 3 have different colors, and the first photoresist layer 1, the second photoresist layer 2 and the third photoresist layer 3 are respectively one of red, green and blue. Since the first photoresist layer 1 and the second photoresist layer 2 are positive photoresist layers and the third photoresist layer 3 is a negative photoresist layer, the patterning of the third photoresist layer 3 can be completed by using the first mask B1 and the second mask B2 that are stacked. Therefore, the color filter substrate 100 can be formed using only two mask plates, thereby simplifying the preparation process of the color filter substrate 100 and saving costs.

[0071] In some embodiments, the light transmittance of the third light-transmitting area C3 of the first mask B1 and the second mask B2 is in the range of 33-67%, for example, it can be 33%, 45%, 66%, etc. The sixth light-transmitting area C6 of the composite mask B is formed by stacking the third light-transmitting area C3 of the first mask B1 and the third light-transmitting area C3 of the second mask B2, and the light transmittance of the sixth light-transmitting area C6 is in the range of 33-67%, for example, it can be 33%, 45%, 66%, etc.

[0072] Specifically, the light transmittance of the third light-transmitting area C3 of the first mask B1 and the second mask B2, and the light transmittance of the sixth light-transmitting area C6 of the composite mask B are used to control the thickness of the first sub-light-shielding layer 21, the second sub-light-shielding layer 22 and the third sub-light-shielding layer 23, respectively. The specific selection can be made according to actual needs and is not limited here.

[0073] In some embodiments, the first photoresist layer 1 is a negative photoresist layer, and the second photoresist layer 2 and the third photoresist layer 3 are positive photoresist layers; or, the second photoresist layer 2 is a negative photoresist layer, and the first photoresist layer 1 and the third photoresist layer 3 are positive photoresist layers. The patterning of the two positive photoresist layers is completed by using the first mask B1 and the second mask B2 respectively, the two photoresist blocks formed by the two positive photoresist layers are respectively arranged corresponding to the first light-transmitting area C1 of the first mask B1 and the second mask B2, the two sub-light-shielding layers formed by the two positive photoresist layers are arranged corresponding to the third light-transmitting area C3 of the first mask B1 and the second mask B2, and the patterning of the negative photoresist layer is completed by using the first mask B1 and the second mask B2 which are stacked.

[0074] Different from the prior art, the beneficial effect of the preparation method of the color filter substrate 100 provided in the present application lies in that, by designing two of the first photoresist layer 1, the second photoresist layer 2 and the third photoresist layer 3 to be positive photoresist layers and the other one to be a negative photoresist layer, when preparing the color filter substrate 100, the mask plates used for patterning the two positive photoresist layers can be stacked to pattern the negative photoresist layer, so that the color filter substrate 100 can be formed using only two mask plates, thereby simplifying the preparation process of the color filter substrate 100 and saving costs.

[0075] See also Fig.10 , Fig.10 The present application also provides a display panel 1000, comprising a color filter substrate 100 and an array substrate 200, wherein the color filter substrate 100 is disposed on one side of the array substrate 200, and the color filter substrate 100 is the color filter substrate 100 provided in any of the above embodiments.

[0076] Among them, the display panel 1000 can be used in mobile phones, computers, tablets, and smart devices such as smart watches.

[0077] In some specific embodiments, a display layer 300 is further provided between the color film substrate 100 and the array substrate 200. Specifically, when the display panel is an LCD display panel, the display layer 300 is a liquid crystal layer. When the display panel is an OLED display panel, an AMOLED display panel, or the like, the display layer 300 is a light-emitting layer.

[0078] The above are only implementation methods of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for preparing a color film substrate, characterized in that: include: Providing a substrate, the substrate comprising a first light block corresponding area, a second light block corresponding area, a third light block corresponding area, and a light shielding corresponding area located between adjacent light block corresponding areas; A first photoresist layer is coated on the substrate and patterned; the patterned first photoresist layer includes a first photoresist block located on a first photoresist block corresponding area and a first sub-light shielding layer located on a light shielding corresponding area; A second photoresist layer is coated on the surface of the first photoresist layer away from the substrate and patterned; the patterned second photoresist layer includes a second photoresist block located on a second photoresist block corresponding area and a second sub-light shielding layer located on a light shielding corresponding area; Coating a third photoresist layer on the surface of the second photoresist layer facing away from the substrate and patterning the third photoresist layer; The patterned third photoresist layer includes a third photoresist block located on a third photoresist block corresponding area and a third sub-light shielding layer located on the light shielding corresponding area; and the first sub-light shielding layer, the second sub-light shielding layer and the third sub-light shielding layer on the light shielding corresponding area are stacked to form a light shielding layer; The first photoresist layer, the second photoresist layer and the third photoresist layer have different colors, and two of them are positive photoresist layers, and the other is a negative photoresist layer; the patterning of the two positive photoresist layers is completed by using a first mask and a second mask respectively, and the patterning of the negative photoresist layer is completed by using the first mask and the second mask which are stacked; Wherein, the first mask and the second mask both include a first light-transmitting area with a light transmittance of 0%, a second light-transmitting area with a light transmittance of 100%, and a third light-transmitting area with a light transmittance range of 33-67%; the two photoresist blocks formed by the two positive photoresist layers are respectively arranged corresponding to the first light-transmitting areas of the first mask and the second mask, and the two sub-shielding layers formed by the two positive photoresist layers are respectively arranged corresponding to the third light-transmitting areas of the first mask and the second mask; The first mask and the second mask are stacked to form a composite mask, which includes a fourth light-transmitting area with a light transmittance of 0%, a fifth light-transmitting area with a light transmittance of 100%, and a sixth light-transmitting area with a light transmittance range of 33-67%; the photoresist block formed by the negative photoresist layer corresponds to the fifth light-transmitting area of ​​the composite mask, and the sub-shielding layer formed by the negative photoresist layer corresponds to the sixth light-transmitting area of ​​the composite mask.

2. The preparation method according to claim 1, characterized in that: The light transmittance of the third light-transmitting area is 50%, the sixth light-transmitting area is formed by stacking the third light-transmitting area of ​​the first mask and the third light-transmitting area of ​​the second mask, and the light transmittance of the sixth light-transmitting area is 50%.

3. The preparation method according to claim 1, characterized in that: The first photoresist layer is a negative photoresist layer; or, The second photoresist layer is a negative photoresist layer; or, The third photoresist layer is a negative photoresist layer.

4. The preparation method according to claim 1, characterized in that: The colors of the first photoresist layer, the second photoresist layer and the third photoresist layer include one of red, green and blue respectively.

5. A color film substrate, characterized in that: The color filter substrate is prepared by the preparation method according to any one of claims 1 to 4; the color filter substrate comprises a plurality of light blocking units, each of which comprises a first light blocking block, a second light blocking block, and a third light blocking block, and a light shielding layer is arranged between two adjacent light blocking blocks, and the light shielding layer comprises a first sub-light shielding layer, a second sub-light shielding layer, and a third sub-light shielding layer which are stacked; Among them, the first photoresist block and the first sub-light-shielding layer are formed by patterning the first photoresist layer, the second photoresist block and the second sub-light-shielding layer are formed by patterning the second photoresist layer, the third photoresist block and the third sub-light-shielding layer are formed by patterning the third photoresist layer, the first photoresist layer, the second photoresist layer and the third photoresist layer have different colors, two of them are positive photoresist layers, and the other is a negative photoresist layer.

6. The color film substrate according to claim 5, characterized in that: The thickness of the first photoresist block, the second photoresist block and the third photoresist block ranges from 1.5 to 6 micrometers, and the thickness of the first sub-light-shielding layer, the second sub-light-shielding layer and the third sub-light-shielding layer ranges from 0.5 to 4 micrometers.

7. The color film substrate according to claim 5, characterized in that: The first light blocking block, the second light blocking block and the third light blocking block have the same thickness; The first sub-light-shielding layer, the second sub-light-shielding layer and the third sub-light-shielding layer have the same thickness; And the thickness of the light shielding layer is greater than the thickness of the first light blocking block, the second light blocking block and the third light blocking block.

8. The color film substrate according to claim 5, characterized in that: The first light block has the same color as the first sub-light-shielding layer, the second light block has the same color as the second sub-light-shielding layer, the third light block has the same color as the third sub-light-shielding layer, and the first light block, the second light block and the third light block respectively include one of red, green and blue.

9. A display panel, characterized in that: include: An array substrate; The color filter substrate is arranged on one side of the array substrate, and the color filter substrate is the color filter substrate according to any one of claims 5 to 8.

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