Reflective display panel and preparation method thereof

Abstract

The invention relates to a reflective display panel and a preparation method thereof. The reflective display panel comprises a first substrate and a second substrate which are oppositely arranged, and a retaining wall structure, a cholesteric liquid crystal layer and an alignment packaging layer which are located between the first substrate and the second substrate; the retaining wall structure is arranged on the surface of the side, close to the second substrate, of the first substrate, the space between the first substrate and the second substrate is divided into a plurality of sub-pixel areas arranged on the same layer, and the retaining wall structure is arranged around the sub-pixel areas; the cholesteric liquid crystal layer is located in the sub-pixel area; the alignment packaging layer is at least located on the surface of the side, close to the cholesteric liquid crystal layer, of the second substrate. The alignment packaging layer comprises a plurality of first alignment packaging units arranged in one-to-one correspondence with the sub-pixel areas, and the first alignment packaging units are at least located in the sub-pixel areas and connected with the adjacent retaining wall structures. By means of the alignment packaging layer, the cholesteric liquid crystal layer can be packaged to prevent cross color, and alignment can be conducted on the cholesteric liquid crystal layer to improve the display effect.

Description

Technical Field

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

[0002] With the advancement of flat display technology, more and more electronic products are equipped with display devices, especially portable electronic products such as mobile phones, e-books, digital cameras, etc. Since portable electronic products are developing towards light weight, small size and thin thickness, the display devices used in portable electronic products must also have the advantages of light weight, small size and thin thickness. In order to promote paperless advertising, electronic billboards such as electrophoretic display devices (EPD) or electronic paper displays (EPD) can replace traditional printed billboards. Electronic billboards are not only light and thin, but can also be designed to be flexible.

[0003] Among them, there are various ways to realize electronic paper, such as electrophoresis, electrowetting, electronic powder fluid, and cholesteric liquid crystal display. However, these display methods all have various problems. For example, the response time of electrophoresis, electrowetting, and electronic powder fluid display methods is relatively slow, and the realization process of cholesteric liquid crystal display method is relatively complicated. Therefore, the existing electronic paper realization methods need to be further improved. Summary of the invention

[0004] The embodiment of the present application provides a reflective display panel and a method for manufacturing the same. The cholesteric liquid crystal layer can be encapsulated by an alignment encapsulation layer to prevent color crosstalk, and the cholesteric liquid crystal layer can also be aligned to improve the display effect.

[0005] In order to achieve the above object, according to a first aspect of the present application, a reflective display panel is provided, comprising:

[0006] A first substrate and a second substrate arranged opposite to each other;

[0007] a retaining wall structure, located between the first substrate and the second substrate; the retaining wall structure is arranged on a surface of the first substrate on a side close to the second substrate, and the retaining wall structure divides the space between the first substrate and the second substrate into a plurality of sub-pixel areas arranged in the same layer, and the retaining wall structure is arranged around each of the sub-pixel areas;

[0008] a cholesteric liquid crystal layer, located in the sub-pixel region; and

[0009] An alignment encapsulation layer is at least located on a surface of the second substrate on a side close to the cholesteric liquid crystal layer;

[0010] The alignment packaging layer includes a plurality of first alignment packaging units aligned with the plurality of sub-pixel regions. In the sub-pixel regions, the first alignment packaging units are located on the surface of the second substrate and connected to the adjacent retaining wall structures.

[0011] In some embodiments, a side of the retaining wall structure close to the second substrate is disposed in contact with a surface of the second substrate; or

[0012] The retaining wall structure is spaced apart from a side of the second substrate close to the second substrate, and the first alignment packaging unit is connected between the spaced apart retaining wall structure and the second substrate.

[0013] In some embodiments, the second substrate includes a substrate layer and a first electrode layer, and the first electrode layer entirely covers a side of the substrate layer close to the cholesteric liquid crystal layer;

[0014] The retaining wall structure is disposed on a surface of the first substrate close to the first electrode layer, and the first alignment encapsulation unit is disposed on a surface of the first electrode layer close to the cholesteric liquid crystal layer and connected to the adjacent retaining wall structure.

[0015] In some embodiments, the alignment encapsulation layer is also located on a surface of the first substrate close to the cholesteric liquid crystal layer, and the alignment encapsulation layer further includes a plurality of second alignment encapsulation units arranged one by one with the plurality of sub-pixel regions;

[0016] In the sub-pixel region, the second alignment packaging unit is located on the surface of the first substrate and is connected to the adjacent barrier wall structure.

[0017] In some embodiments, the first substrate includes a driving circuit layer and a second electrode layer electrically connected to each other, the second electrode layer includes a plurality of electrode blocks located on a side of the driving circuit layer close to the cholesteric liquid crystal layer, and the plurality of electrode blocks are aligned with the plurality of sub-pixel regions one by one; the retaining wall structure is located between any two adjacent electrode blocks;

[0018] The second alignment encapsulation unit is disposed on a surface of the electrode block on a side close to the cholesteric liquid crystal layer and is connected to the adjacent retaining wall structure.

[0019] In some embodiments, the material of the alignment encapsulation layer includes a self-aligned polymer, the self-aligned polymer includes an alignment group, and the alignment group includes a chain group composed of a plurality of cyclic groups.

[0020] In some embodiments, the material of the cholesteric liquid crystal layer includes light-controlled cholesteric liquid crystal or temperature-controlled cholesteric liquid crystal;

[0021] The multiple sub-pixel areas include multiple first sub-pixel areas and multiple second sub-pixel areas, the material of the cholesteric liquid crystal layer located in the first sub-pixel area and the second sub-pixel area is the same, and the pitch of the cholesteric liquid crystal layer located in the first sub-pixel area is different from the pitch of the cholesteric liquid crystal layer located in the second sub-pixel area.

[0022] In order to achieve the above object, according to the second aspect of the present application, a method for preparing a reflective display panel is provided, and the preparation method comprises the following steps:

[0023] A retaining wall structure is formed on one side of the first substrate; the retaining wall structure is provided with a plurality of pixel openings exposing the first substrate, and the plurality of pixel openings divide a plurality of sub-pixel areas;

[0024] Adding a liquid crystal composition into each of the pixel openings; the liquid crystal composition comprises a cholesteric liquid crystal and a polymerizable monomer; the polymerizable monomer comprises an anchoring group, a polymerizable group and an alignment group;

[0025] A second substrate is arranged on a side of the retaining wall structure away from the first substrate to form a liquid crystal box; at least a side of the second substrate close to the first substrate has a polar functional group;

[0026] Controlling the polymerizable monomers in the liquid crystal composition to undergo a polymerization reaction at least on the surface of the second substrate to form an alignment encapsulation layer; the alignment encapsulation layer comprises a first alignment encapsulation unit arranged one by one with the plurality of sub-pixel regions, wherein within the sub-pixel region, the first alignment encapsulation unit is located on the surface of the second substrate and connected to the adjacent retaining wall structure; and

[0027] The pitches of the cholesteric liquid crystals in different pixel openings are adjusted to form a cholesteric liquid crystal layer.

[0028] In some embodiments, the chemical structure of the polymerizable monomer is as shown in Formula I:

[0029]

[0030] Wherein, A represents the anchoring group, B and C represent the polymerizable groups, and D represents the alignment group; the anchoring group contains at least one hydroxyl group, the polymerizable group contains at least one carbon-carbon double bond, and the alignment group contains a chain group composed of multiple cyclic groups.

[0031] In some embodiments, the cholesteric liquid crystal includes light-controlled cholesteric liquid crystal or temperature-controlled cholesteric liquid crystal;

[0032] The step of forming the alignment encapsulation layer comprises:

[0033] Illuminating the entire surface of the liquid crystal box so that the polymerizable monomers in the liquid crystal composition undergo a polymerization reaction at least on the surface of the second substrate to form the alignment encapsulation layer;

[0034] The steps of forming the cholesteric liquid crystal layer include:

[0035] The cholesteric liquid crystals in different pixel openings are subjected to illumination treatments with different integrated light amounts or heating treatments with different temperatures, so that the cholesteric liquid crystals in different pixel openings have different helical pitches.

[0036] In the reflective display panel and its preparation method of the embodiment of the present application, by setting a retaining wall structure between the first substrate and the second substrate, a plurality of sub-pixel areas can be defined, and the cholesteric liquid crystal layer can be restricted to the plurality of sub-pixel areas by the retaining wall structure, so as to prevent the cholesteric liquid crystal layer from flowing between different sub-pixel areas, thereby improving the problem of color crosstalk. In addition, an alignment encapsulation layer is set on the surface of at least the second substrate, and the alignment encapsulation layer can extend from the surface of the second substrate close to the side of the cholesteric liquid crystal layer to connect with the adjacent retaining wall structure, thereby realizing the encapsulation effect of the cholesteric liquid crystal layer, and further preventing the cholesteric liquid crystal after the box from flowing between different sub-pixel areas, thereby effectively solving the problem of color crosstalk. At the same time, the alignment encapsulation layer can also align the cholesteric liquid crystal layer, thereby improving the reflectivity of the cholesteric liquid crystal, and then improving the display effect. Therefore, the embodiment of the present application can encapsulate the cholesteric liquid crystal layer to prevent color crosstalk through the alignment encapsulation layer, and can also align the cholesteric liquid crystal layer to improve the display effect.

[0037] Other features and advantages of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can obtain other drawings based on these drawings without creative work.

[0039] In order to more completely understand the present application and its beneficial effects, the following description will be given in conjunction with the accompanying drawings, wherein the same figure numbers represent the same parts in the following description.

[0040] Figure 1 is a schematic diagram of the structure of a traditional electronic paper display panel;

[0041] Figure 2 is a top view of an exemplary retaining wall structure;

[0042] Figure 3 is a structural schematic diagram of a reflective display panel provided in an embodiment of the present application;

[0043] Figure 4 is a schematic structural diagram of another reflective display panel provided in an embodiment of the present application;

[0044] Figure 5 It is a schematic flow chart of a method for preparing a reflective display panel provided in an embodiment of the present application;

[0045] Figure 6 and Figure 7 It is a structural schematic diagram of preparing a retaining wall structure in the method for preparing a reflective display panel provided in an embodiment of the present application;

[0046] Figure 8 It is a schematic diagram of the structure after the liquid crystal composition is injected in the method for preparing the reflective display panel provided in the embodiment of the present application;

[0047] Fig. 9 It is a structural schematic diagram of forming a liquid crystal cell in the method for preparing a reflective display panel provided in an embodiment of the present application;

[0048] Fig.10 It is a schematic diagram of using UV light to illuminate the entire surface of a liquid crystal box in a method for preparing a reflective display panel provided in an embodiment of the present application;

[0049] Fig.11 It is a schematic structural diagram of a reflective display panel manufacturing method provided in an embodiment of the present application after an alignment encapsulation layer is formed;

[0050] Fig.12 It is a schematic diagram of using UV light to illuminate a sub-pixel area through a halftone mask in a method for preparing a reflective display panel provided in an embodiment of the present application;

[0051] Fig.13 It is a schematic diagram of illuminating a sub-pixel area using UV or IR light through direct laser imaging provided in an embodiment of the present application. DETAILED DESCRIPTION

[0052] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0053] like Figure 1As shown, a conventional electronic paper display panel 1 comprises a first substrate 2, a second substrate 3 arranged opposite to the first substrate 2, a first cholesteric liquid crystal layer 4 arranged between the first substrate 2 and the second substrate 3, a third substrate 5 arranged on the second substrate 3, a fourth substrate 6 arranged opposite to the third substrate 5, and a second cholesteric liquid crystal layer 7 arranged between the third substrate 5 and the fourth substrate 6. The electronic paper display panel 1 has a plurality of sub-pixel regions, and the plurality of sub-pixel regions include a first sub-pixel region 8 emitting white light, a second sub-pixel region 9 emitting red light, a third sub-pixel region 10 emitting cyan light, and a fourth sub-pixel region 11 in a dark state. The first cholesteric liquid crystal layer 4 includes a first cholesteric liquid crystal 12 located in the first sub-pixel area 8 and the second sub-pixel area 9 and reflecting red light, and a second cholesteric liquid crystal 13 located in the third sub-pixel area 10 and the fourth sub-pixel area 11 and not reflecting light; the second cholesteric liquid crystal layer 7 includes a third cholesteric liquid crystal 14 located in the first sub-pixel area 8 and the third sub-pixel area 10 and reflecting cyan-blue light, and a second cholesteric liquid crystal 13 located in the second sub-pixel area 9 and the fourth sub-pixel area 11 and not reflecting light.

[0054] Specifically, the electronic paper display panel 1 further includes a light absorbing layer (e.g., a black ink layer) 15 located on the side of the first substrate 2 away from the second substrate 3. Since the second cholesteric liquid crystal 13 does not reflect light, external light can pass through the second cholesteric liquid crystal 13. Therefore, when the first cholesteric liquid crystal layer 4 and the second cholesteric liquid crystal layer 7 in the same sub-pixel area (e.g., the fourth sub-pixel area 11) are both the second cholesteric liquid crystal 13, the external light can pass through the sub-pixel area and be absorbed by the light absorbing layer 15, so that the sub-pixel area is in a dark state.

[0055] Specifically, the first cholesteric liquid crystal layer 4 and the second cholesteric liquid crystal layer 7 located in the first sub-pixel region 8 are respectively the first cholesteric liquid crystal 12 reflecting red light and the third cholesteric liquid crystal 14 reflecting cyan light, so the first sub-pixel region 8 emits white light. The first cholesteric liquid crystal layer 4 and the second cholesteric liquid crystal layer 7 located in the second sub-pixel region 9 are respectively the first cholesteric liquid crystal 12 reflecting red light and the second cholesteric liquid crystal 13 not reflecting light, so the second sub-pixel region 9 emits red light. The first cholesteric liquid crystal layer 4 and the second cholesteric liquid crystal layer 7 located in the third sub-pixel region 10 are respectively the third cholesteric liquid crystal 14 reflecting cyan light and the second cholesteric liquid crystal 13 not reflecting light, so the third sub-pixel region 10 emits cyan light. The first cholesteric liquid crystal layer 4 and the second cholesteric liquid crystal layer 7 located in the fourth sub-pixel region 11 are both the second cholesteric liquid crystal 13 not reflecting light, so the fourth sub-pixel region 11 is in a dark state. Since the first sub-pixel region 8 , the second sub-pixel region 9 and the third sub-pixel region 10 can emit white light, red light and cyan light respectively, full-color display can be achieved.

[0056] Specifically, each sub-pixel area (eg Figure 1 The first sub-pixel region 8, the second sub-pixel region 9, the third sub-pixel region 10 and the fourth sub-pixel region 11) can be Figure 2 The plurality of crisscross retaining wall structures 16 shown are defined. In other words, Figure 2 Each pixel opening 17 surrounded by the retaining wall structure 16 corresponds to a sub-pixel area.

[0057] Although Figure 1 The structure shown can realize full-color electronic paper display, but the electronic paper display panel 1 needs to be formed by two stacked liquid crystal boxes, and the structures of the cholesteric liquid crystal layers in the two liquid crystal boxes are different, resulting in a large thickness of the electronic paper display panel 1 and a relatively complex manufacturing process, which is not conducive to achieving lightness and thinness and reducing manufacturing costs. In addition, since the retaining wall structure 16 cannot bond the upper and lower substrates at the same time, the liquid crystal material after the box is formed will flow between different sub-pixel areas, resulting in cross-color.

[0058] In order to solve the above technical problems, the embodiment of the present application provides a reflective display panel and a preparation method thereof, wherein a plurality of sub-pixel areas are defined by setting a retaining wall structure between the upper and lower substrates, and by adding an appropriate amount of self-alignment material to the cholesteric liquid crystal during the boxing process, and then forming an alignment encapsulation layer on the upper substrate and / or the lower substrate through a lighting process, the alignment encapsulation layer can align the cholesteric liquid crystal to improve the reflectivity of the cholesteric liquid crystal, and can also encapsulate the cholesteric liquid crystal so that the cholesteric liquid crystal after the boxing will not flow between different sub-pixel areas, thereby effectively solving the problem of cross-color. In addition, the material of the cholesteric liquid crystal used in each sub-pixel area of ​​the present application is the same, and the cholesteric liquid crystal is a light-controlled cholesteric liquid crystal or a temperature-controlled cholesteric liquid crystal, so that after the formation of the alignment encapsulation layer, the cholesteric liquid crystal in each sub-pixel area can be illuminated with different integrated light or different temperatures, so that the cholesteric liquid crystals in different sub-pixel areas have different pitches, thereby realizing the color display of a single-layer panel.

[0059] like Figure 2 and Figure 3As shown, the embodiment of the present application provides a reflective display panel 20, which includes a first substrate 21, a second substrate 22, a retaining wall structure 23, a cholesteric liquid crystal layer 24 and an alignment encapsulation layer 25. The first substrate 21 and the second substrate 22 are arranged opposite to each other, and the retaining wall structure 23 is located between the first substrate 21 and the second substrate 22. The retaining wall structure 23 is arranged on the surface of the first substrate 21 on the side close to the second substrate 22, so that the side of the retaining wall structure 23 close to the first substrate 21 is attached to and fixedly arranged on the surface of the first substrate 21. The retaining wall structure 23 divides the space between the first substrate 21 and the second substrate 22 into a plurality of sub-pixel areas 26 arranged in the same layer, and the retaining wall structure 23 is arranged around each sub-pixel area 26. The cholesteric liquid crystal layer 24 is located in the sub-pixel area 26, and the alignment encapsulation layer 25 is at least located on the surface of the second substrate 22 on the side close to the cholesteric liquid crystal layer 24.

[0060] The alignment encapsulation layer 25 includes a plurality of first alignment encapsulation units 25a which are spaced apart from each other and aligned with the plurality of sub-pixel regions 26. In each sub-pixel region 26, the first alignment encapsulation unit 25a is located on the surface of the second substrate 22 and connected to the adjacent retaining wall structure 23. In other words, the first alignment encapsulation unit 25a extends from the surface of the second substrate 22 to connect to the adjacent retaining wall structure 23 in each sub-pixel region 26.

[0061] It can be understood that the reflective display panel 20 provided in the embodiment of the present application is an electronic paper display panel. In the embodiment of the present application, a plurality of sub-pixel areas 26 are defined by providing a retaining wall structure 23 between the first substrate 21 and the second substrate 22 .

[0062] In a specific embodiment, Figure 2 As shown, the retaining wall structure 23 is composed of a plurality of crisscross retaining wall units, that is, the retaining wall structure 23 is provided with a plurality of pixel openings 23a distributed in an array, and the area where each pixel opening 23a is located is a sub-pixel area 26. It can be understood that each pixel opening 23a runs through the retaining wall structure 23.

[0063] In some embodiments, the height of the retaining wall structure 23 in the thickness direction of the reflective display panel 20 ranges from 5 micrometers (um) to 30um. In a preferred embodiment, the height of the retaining wall structure 23 in the thickness direction of the reflective display panel 20 ranges from 10um to 20um.

[0064] Generally, the height of the retaining wall structure 23 determines the thickness of the liquid crystal box. In the embodiment of the present application, by limiting the thickness of the retaining wall structure 23 within a suitable range, it is possible to achieve a good display effect while ensuring that the alignment encapsulation layer 25 can be smoothly formed. The alignment encapsulation layer 25 in the embodiment of the present application is formed by a polymerization reaction (or a cross-linking reaction) on the surface of the substrate by irradiation with light after the box is formed. Therefore, when the height of the retaining wall structure 23 is too large, it will affect the film thickness and uniformity of the alignment encapsulation layer 25. When the height of the retaining wall structure 23 is too small, it will affect the configuration of the pitch of the cholesteric liquid crystal in the cholesteric liquid crystal layer 24.

[0065] Specifically, the retaining wall structure 23 may be made of a transparent material or a light-shielding material, which is not limited in the embodiment of the present application.

[0066] In some embodiments, the width of the retaining wall structure 23 ranges from 3um to 10um. The length of the retaining wall structure 23 is designed according to the size requirements of the sub-pixel. It should be noted that the width of the retaining wall structure 23 refers to the width of the retaining wall structure 23 located between two adjacent sub-pixel areas 26, which is equivalent to the spacing between two adjacent sub-pixel areas 26.

[0067] Specifically, the retaining wall structure 23 can be manufactured by using a yellow light process or a nano-imprinting process, which is not limited in the embodiment of the present application.

[0068] In some embodiments, the retaining wall structure 23 is prepared and formed on the first substrate 21, so the retaining wall structure 23 is arranged on the surface of the first substrate 21 on the side close to the second substrate 22, so that the side of the retaining wall structure 23 close to the first substrate 21 is fitted and fixedly connected to the surface of the first substrate 21. During the process of assembling the second substrate 22 and the first substrate 21, the surfaces of the retaining wall structure 23 and the second substrate 22 can be fitted, but the two cannot be fixedly connected. In some cases, there may even be a gap between the surfaces of the retaining wall structure 23 and the second substrate 22. Therefore, if the cholesteric liquid crystal layer 24 is not encapsulated, the cholesteric liquid crystal materials between the multiple sub-pixel areas 26 may flow to each other through the gap between the retaining wall structure 23 and the second substrate 22, thereby causing cross-color and affecting the display effect.

[0069] In a specific embodiment, Figure 3 As shown, the retaining wall structure 23 is arranged to be bonded to the surface of the second substrate 22 on one side close to the second substrate 22, and the first alignment packaging unit 25a extends from the surface of the second substrate 22 in the corresponding sub-pixel area 26 to connect with the adjacent retaining wall structure 23, so that the retaining wall structure 23 and the second substrate 22 are fixedly connected through the first alignment packaging unit 25a.

[0070] Although the side of the retaining wall structure 23 close to the second substrate 22 is fitted with the surface of the second substrate 22, since the two are not fixedly connected, in other manufacturing processes or when the finished panel is used, under the action of external force, it is very likely that a gap will appear between the retaining wall structure 23 and the surface of the second substrate 22, thereby causing the cholesteric liquid crystal materials between the multiple sub-pixel areas 26 to flow to each other, thereby causing cross-color and affecting the display effect.

[0071] In order to solve the problem of cross-color, the embodiment of the present application arranges the alignment encapsulation layer 25 at least on one side of the second substrate 22 close to the cholesteric liquid crystal layer 24, and the first alignment encapsulation unit 25a extends from the surface of the second substrate 22 in the corresponding sub-pixel area 26 to connect with the adjacent retaining wall structure 23, which is equivalent to blocking the position between the retaining wall structure 23 and the second substrate 22 by setting the first alignment encapsulation unit 25a in each sub-pixel area 26, thereby realizing the encapsulation of the cholesteric liquid crystal material in the sub-pixel area 26, which can effectively prevent the cholesteric liquid crystal materials between multiple sub-pixel areas 26 from flowing to each other, thereby solving the problem of cross-color.

[0072] In another specific embodiment, Figure 4 As shown, the side of the retaining wall structure 23 close to the second substrate 22 is spaced apart from the second substrate 22, that is, there is a gap between the retaining wall structure 23 and the second substrate 22; the first alignment encapsulation unit 25a extends from the corresponding sub-pixel area 26 to between the adjacent retaining wall structure 23 and the second substrate 22, and the first alignment encapsulation unit 25a is connected to the side of the adjacent retaining wall structure 23 close to the second substrate 22. That is, the first alignment encapsulation unit 25a is connected between the spaced retaining wall structure 23 and the second substrate 22.

[0073] It should be noted that the spacing between the side of the retaining wall structure 23 close to the second substrate 22 and the second substrate 22 is greater than 0, which may be caused by process errors, or it may be set to make the cholesteric liquid crystal material in the multiple sub-pixel areas 26 more evenly distributed. In the case where the spacing between the side of the retaining wall structure 23 close to the second substrate 22 and the second substrate 22 is greater than 0, the cross-color problem will inevitably occur during the use of the finished panel. Therefore, in the embodiment of the present application, the first alignment encapsulation unit 25a is extended from the corresponding sub-pixel area 26 to between the adjacent retaining wall structure 23 and the second substrate 22, and the first alignment encapsulation unit 25a is connected to the side of the adjacent retaining wall structure 23 close to the second substrate 22, so that the gap between the retaining wall structure 23 and the second substrate 22 can be blocked, thereby realizing the encapsulation of the cholesteric liquid crystal material in the sub-pixel area 26, and the cholesteric liquid crystal material between the multiple sub-pixel areas 26 can be effectively prevented from flowing to each other, thereby solving the cross-color problem.

[0074] It can be understood that when the retaining wall structure 23 is spaced apart from the second substrate 22 on one side thereof, the first alignment encapsulation unit 25a can be completely filled between the adjacent retaining wall structure 23 and the second substrate 22, or can be only partially filled between the adjacent retaining wall structure 23 and the second substrate 22. For example, the first alignment encapsulation unit 25a fills the gap between the adjacent retaining wall structure 23 and the second substrate 22 on one side thereof, close to the corresponding sub-pixel area 26, as long as the cholesteric liquid crystal material in the sub-pixel area 26 can be encapsulated.

[0075] In some embodiments, Figure 3 As shown, the second substrate 22 includes a substrate layer 22a and a first electrode layer 22b, and the first electrode layer 22b covers the entire surface of the substrate layer 22a on the side close to the cholesteric liquid crystal layer 24. The retaining wall structure 23 is arranged on the surface of the first substrate 21 on the side close to the first electrode layer 22b, and the retaining wall structure 23 is arranged close to the first electrode layer 22b on the side away from the first substrate 21. The first alignment encapsulation unit 25a is located on the surface of the first electrode layer 22b on the side close to the cholesteric liquid crystal layer 24, and is connected to the adjacent retaining wall structure 23.

[0076] In some embodiments, the substrate layer 22a is a transparent glass substrate, the first electrode layer 22b is also transparent, and the material of the first electrode layer 22b includes metal oxide, for example, the material of the first electrode layer 22b is indium tin oxide (ITO), but is not limited thereto.

[0077] In some embodiments, Figure 3 and Figure 4 As shown, the alignment encapsulation layer 25 is also located on the surface of the first substrate 21 near the cholesteric liquid crystal layer 24, and the alignment encapsulation layer 25 also includes a plurality of second alignment encapsulation units 25b arranged one by one with the plurality of sub-pixel regions 26. In each sub-pixel region 26, the second alignment encapsulation unit 25b is located on the surface of the first substrate 21 and is connected to the adjacent retaining wall structure 26. In other words, the second alignment encapsulation unit 25b extends from the surface of the first substrate 21 to the adjacent retaining wall structure 23 in the sub-pixel region 26.

[0078] It can be understood that the alignment encapsulation layer 25 can be formed only on the surface of the second substrate 22, or can be formed on the surfaces of the first substrate 21 and the second substrate 22 at the same time. When the alignment encapsulation layer 25 is formed only on the surface of the second substrate 22, the alignment encapsulation layer 25 can realize the encapsulation function of the cholesteric liquid crystal layer 24, and can realize the alignment function of the cholesteric liquid crystal layer 24 to a certain extent; when the alignment encapsulation layer 25 is formed on the surfaces of the first substrate 21 and the second substrate 22 at the same time, the alignment encapsulation layer 25 can enhance the alignment function of the cholesteric liquid crystal layer 24 on the basis of realizing the encapsulation function of the cholesteric liquid crystal layer 24, thereby more effectively improving the reflectivity of the cholesteric liquid crystal layer 24, and further more effectively improving the display effect.

[0079] It should be noted that the alignment effect of the alignment encapsulation layer 25 can improve the stability of the cholesteric liquid crystal, thereby increasing the reflectivity of the cholesteric liquid crystal layer 24, thereby improving the display contrast, and ultimately achieving an improved display effect.

[0080] In some embodiments, Figure 3 As shown, the first substrate 21 includes a driving circuit layer 21a and a second electrode layer 21b electrically connected to each other, the second electrode layer 21b includes a plurality of electrode blocks 21c located on the side of the driving circuit layer 21a close to the cholesteric liquid crystal layer 24, and the plurality of electrode blocks 21c are arranged one by one with the plurality of sub-pixel areas 26; the retaining wall structure 23 is located between any two adjacent electrode blocks 21c. The second alignment encapsulation unit 25b is arranged on the side of the electrode block 21c close to the cholesteric liquid crystal layer 24, and is connected to the adjacent retaining wall structure 23.

[0081] It can be understood that the first substrate 21 is a driving substrate, the second substrate 22 is an opposing substrate, and the side of the second substrate 22 away from the first substrate 21 is a light emitting side. At this time, the side of the retaining wall structure 23 close to the first substrate 21 is attached to and fixedly arranged on the surface of the driving circuit layer 21a. Of course, if other film layers are provided on the surface of the driving circuit layer 21a, the side of the retaining wall structure 23 close to the first substrate 21 is attached to and fixedly arranged on the surface of the other film layers on the driving circuit layer 21a.

[0082] In some embodiments, the driving circuit layer 21 a includes a plurality of thin film transistors (TFTs), and the switching state of each sub-pixel region 26 can be controlled by the TFTs.

[0083] In some embodiments, each electrode block 21c is in contact with the adjacent retaining wall structure 23, that is, the distance between the two is equal to 0. Of course, the retaining wall structure 23 may also partially cover the electrode block 21c.

[0084] It should be noted that, in other embodiments, the first substrate may be an opposing substrate, and correspondingly, the second substrate is a driving substrate. In this case, the retaining wall structure is formed on the first electrode layer disposed on the entire surface of the first substrate, that is, the side of the retaining wall structure close to the first substrate is attached to and fixedly disposed on the surface of the first electrode layer. The embodiment of the present application is described only by taking the retaining wall structure formed on the driving substrate as an example.

[0085] In some embodiments, the material of the alignment encapsulation layer 25 includes a self-aligned polymer, the self-aligned polymer includes an alignment group, and the alignment group includes a chain group composed of multiple cyclic groups. It can be understood that the polymerized monomer of the self-aligned polymer includes an anchor group, a polymerizable group and an alignment group, wherein the anchor group includes at least one hydroxyl group, and the polymerizable group includes at least one carbon-carbon double bond.

[0086] It should be noted that the cyclic substrate includes substituted or unsubstituted cycloalkane groups, substituted or unsubstituted aromatic ring groups, and different cyclic groups can be directly connected by single bonds or by connecting groups. The embodiments of the present application do not limit the type of connecting groups.

[0087] It should be noted that, in the process of preparing the reflective display panel 20, an appropriate amount of polymerizable monomer (refer to Fig. 9 The polymerizable monomer 29 in the cholesteric liquid crystal is added. When the cholesteric liquid crystal material containing the polymerizable monomer is injected into the pixel opening 23a of the retaining wall structure 23 and arranged in a box, the entire surface of the liquid crystal box can be illuminated (for example, ultraviolet (UV) light), so that the polymerizable monomer moves to the target substrate (for example, the second substrate 22) and is anchored to the surface of the target substrate through the hydroxyl group in the anchoring group. At the same time, the carbon-carbon double bond in the polymerizable monomer opens and undergoes a polymerization reaction (for example, a cross-linking reaction), thereby forming a self-aligned polymer on the surface of the target substrate, and then forming an alignment encapsulation layer 25. Since the polymerizable monomer also includes a chain group composed of multiple cyclic groups, the self-aligned polymer formed also contains the chain group, which is arranged at a preset angle between the chain group and the target substrate as a steric obstacle, thereby realizing the alignment function of the cholesteric liquid crystal.

[0088] It can be understood that the self-aligned polymer comprises a plurality of repeating molecular segments, each repeating molecular segment comprises the above-mentioned anchoring group and alignment group, and two adjacent repeating molecular segments are connected by the above-mentioned polymerizable group. In other words, the repeating molecular segment is a structure formed after the carbon-carbon double bond on the polymerizable group in the polymerized monomer is opened.

[0089] In some embodiments, the polymerizable group is a photoreactive group, that is, when the cholesteric liquid crystal material containing the polymerizable monomer is illuminated, the polymerizable monomer can move toward the target substrate (the first substrate 21 and / or the second substrate 22), thereby being anchored to the target substrate, and the polymerizable monomers can undergo a polymerization reaction through the polymerizable group to form an alignment encapsulation layer 25. Of course, other polymerizable compounds can also be added to the cholesteric liquid crystal material, and when the cholesteric liquid crystal material containing the polymerizable monomer is illuminated, the polymerizable monomer can also undergo a polymerization reaction with the polymerizable compound.

[0090] In one embodiment, the polymerizable group is selected from acrylic groups, but is not limited thereto.

[0091] In some embodiments, the first substrate 21 and / or the second substrate 22 need to be cleaned before being boxed, and the cleaning process must include an ultraviolet irradiation process, such as an extreme ultraviolet (EUV) irradiation process, which can modify the surface of the electrode layer (e.g., ITO layer) on the target substrate (the first substrate 21 and / or the second substrate 22) so that polar functional groups (e.g., hydroxyl groups) are generated on the corresponding electrode layer. When the surface of the electrode layer carries polar functional groups, the anchoring groups on the polymerized monomers can be anchored to the surface of the target substrate (i.e., the surface of the electrode layer), so that the formed self-aligned polymer is tightly combined with the surface of the target substrate, thereby making the formed alignment encapsulation layer 25 fixedly connected to the target substrate.

[0092] In a specific embodiment, the chemical structural formula of the polymerized monomer of the organic polymer is as shown in Formula I:

[0093]

[0094] Wherein, A represents an anchoring group, B and C represent polymerizable groups, and D represents an alignment group.

[0095] It can be understood that the repeating molecular segment is a structure formed after the carbon-carbon double bonds on the B and C groups are opened.

[0096] In one specific embodiment, A contains a group represented by formula II, B and C contain a group represented by formula III-1 or III-2, and D contains a group represented by formula IV:

[0097]

[0098] Wherein, R1 and R2 represent alkyl groups, and “*” represents a connection site.

[0099] In some embodiments, R1 and R2 are selected from alkyl groups, but are not limited thereto.

[0100] In one embodiment, R1 is selected from -C5H 11 , R2 is selected from -C2H5.

[0101] It should be noted that the groups shown in Formula II, Formula III-1, Formula III-2 or Formula IV and the main structure When connecting, the connection can be carried out through a connecting group, and the connecting group includes but is not limited to an alkyl group.

[0102] Of course, the embodiments of the present application do not limit the specific chemical structure of the polymerized monomer. The above is an example. As long as the polymerized monomer can satisfy the self-alignment function and has no negative impact on the cholesteric liquid crystal material, it is applicable to the present application.

[0103] In some embodiments, the material of the cholesteric liquid crystal layer 24 includes light-controlled cholesteric liquid crystal or temperature-controlled cholesteric liquid crystal. Figure 3 As shown, the multiple sub-pixel areas 26 include multiple first sub-pixel areas 26a and multiple second sub-pixel areas 26b, the material of the cholesteric liquid crystal layer 24 located in the first sub-pixel area 26a and the second sub-pixel area 26b is the same, and the pitch of the cholesteric liquid crystal layer 24 located in the first sub-pixel area 26a is different from the pitch of the cholesteric liquid crystal layer 24 located in the second sub-pixel area 26b.

[0104] In some embodiments, Figure 3 As shown, the multiple sub-pixel areas 26 also include multiple third sub-pixel areas 26c, the material of the cholesteric liquid crystal layer 24 located in the first sub-pixel area 26a, the second sub-pixel area 26b and the third sub-pixel area 26c is the same, and the pitches of the cholesteric liquid crystal layer 24 located in the first sub-pixel area 26a, the second sub-pixel area 26b and the third sub-pixel area 26c are different from each other.

[0105] Specifically, since the pitches of the cholesteric liquid crystal layer 24 located in the first sub-pixel region 26a, the second sub-pixel region 26b and the third sub-pixel region 26c are different, the first sub-pixel region 26a, the second sub-pixel region 26b and the third sub-pixel region 26c can reflect light of different colors, thereby achieving color display.

[0106] In one embodiment, the cholesteric liquid crystal layer 24 in the first sub-pixel region 26a reflects red light, the cholesteric liquid crystal layer 24 in the second sub-pixel region 26b reflects green light, and the cholesteric liquid crystal layer 24 in the third sub-pixel region 26c reflects blue light.

[0107] In a specific embodiment, the material of the light-controlled cholesteric liquid crystal includes cholesteric liquid crystal and chiral switch molecules; the chiral switch molecules include any one or more of azobenzene, diarylethenes, molecular motors, cyanovinyl and spiropyran.

[0108] It should be noted that the embodiments of the present application do not limit the material of the temperature-controlled cholesteric liquid crystal, and all temperature-controlled cholesteric liquid crystals sold on the market can be applied to the present application.

[0109] When the material of the cholesteric liquid crystal layer 24 is selected from light-controlled cholesteric liquid crystal, taking the first sub-pixel area 26a, the second sub-pixel area 26b and the third sub-pixel area 26c that reflect different colors as an example, UV light can be used to illuminate the three sub-pixel areas (26a, 26b, 26c) with different integrated light amounts, so that the light-controlled cholesteric liquid crystals located in the three sub-pixel areas (26a, 26b, 26c) receive different integrated light amounts, and finally the light-controlled cholesteric liquid crystals in the three sub-pixel areas (26a, 26b, 26c) have different pitches, thereby achieving full-color display.

[0110] In some embodiments, Fig.12 As shown, a halftone mask 30 can be used to simultaneously perform UV irradiation on the three sub-pixel areas (26a, 26b, 26c). Since the halftone mask 30 has three light-transmitting areas with different transmittances, and each light-transmitting area has the same size as the corresponding sub-pixel area, it can be achieved that when the irradiation time is the same, the light-controlled cholesteric liquid crystals located in the three sub-pixel areas (26a, 26b, 26c) receive different amounts of integrated light, thereby making the light-controlled cholesteric liquid crystals located in the three sub-pixel areas (26a, 26b, 26c) have different pitches.

[0111] In other embodiments, Fig.13 As shown, laser direct imaging (LDI) can also be used to perform independent UV irradiation on the sub-pixel area 26 of each color, and different integrated light amounts are irradiated on the sub-pixel areas of different colors, so that the light-controlled cholesteric liquid crystals located in the three sub-pixel areas (26a, 26b, 26c) receive different integrated light amounts, thereby making the light-controlled cholesteric liquid crystals located in the three sub-pixel areas (26a, 26b, 26c) have different helical pitches.

[0112] In a specific implementation, the cholesteric liquid crystal layer 24 may be illuminated by LDI, which can save masks and achieve mask-free pixel-level illumination, thereby helping to improve display effects while saving manufacturing costs.

[0113] It can be understood that when the material of the cholesteric liquid crystal layer 24 is selected from light-controlled cholesteric liquid crystal, two illumination processes are required during the production process of the reflective display panel 20. The first is full-surface illumination to form the alignment encapsulation layer 25, and the second is selective illumination of different sub-pixel areas 26 to change the pitch of the cholesteric liquid crystal in different sub-pixel areas 26.

[0114] When the material of the cholesteric liquid crystal layer 24 is selected from temperature-controlled cholesteric liquid crystal, taking the first sub-pixel region 26a, the second sub-pixel region 26b and the third sub-pixel region 26c reflecting different colors as an example, Fig.13 As shown, infrared (IR) light can be used to illuminate the liquid crystal box. Specifically, the LDI method can be used to illuminate three different sub-pixel areas (26a, 26b, 26c). By controlling the illumination time, the cholesteric liquid crystal sensing temperature is changed, so that the temperature of the cholesteric liquid crystal in different sub-pixel areas is different, thereby making the pitch of the cholesteric liquid crystal in different sub-pixel areas different, thereby achieving different reflection colors.

[0115] In the embodiment of the present application, a retaining wall structure 23 is provided between the first substrate 21 and the second substrate 22, so that a plurality of sub-pixel areas 26 can be defined, and the cholesteric liquid crystal layer 24 can be limited to the plurality of sub-pixel areas 26 by the retaining wall structure 23, so as to prevent the cholesteric liquid crystal layer 24 from flowing between different sub-pixel areas 26, thereby improving the problem of cross-color. In addition, an alignment encapsulation layer 25 is provided at least on the surface of the second substrate 22, and the alignment encapsulation layer 25 can extend from the surface of the second substrate 22 close to the cholesteric liquid crystal layer 24 to connect with the adjacent retaining wall structure 23, thereby achieving the encapsulation of the cholesteric liquid crystal layer 24, and further preventing the cholesteric liquid crystal after the box from flowing between different sub-pixel areas 26, thereby more effectively solving the problem of cross-color. At the same time, the alignment encapsulation layer 25 can also align the cholesteric liquid crystal layer 24, thereby improving the reflectivity of the cholesteric liquid crystal layer 24, thereby improving the display effect. Therefore, in the embodiment of the present application, the alignment encapsulation layer 25 can be used to encapsulate the cholesteric liquid crystal layer 24 to prevent cross-coloring, and can also align the cholesteric liquid crystal layer 24 to improve the display effect.

[0116] In addition, the material of the cholesteric liquid crystal used in each sub-pixel area 26 of the reflective display panel 20 provided in the embodiment of the present application is the same, and the cholesteric liquid crystal is a light-controlled cholesteric liquid crystal or a temperature-controlled cholesteric liquid crystal, so that after the alignment encapsulation layer 25 is formed, the cholesteric liquid crystal in each sub-pixel area 26 can be illuminated with different integrated light amounts or different times (or temperatures), so that the cholesteric liquid crystals in different sub-pixel areas 26 have different pitches. This design can not only simplify the process flow of liquid crystal dripping, but also realize reflective color display of a single panel.

[0117] and Figure 1 Compared with the traditional electronic paper display panel shown, the reflective display panel 20 provided in the embodiment of the present application has a simpler structure and can effectively prevent the cross-color problem.

[0118] like Figure 5As shown, the embodiment of the present application further provides a method for preparing the reflective display panel provided in the above embodiment, and the preparation method includes steps S501 to S505.

[0119] S501: forming a retaining wall structure on one side of a first substrate; a plurality of pixel openings exposing the first substrate are provided on the retaining wall structure, and the plurality of pixel openings divide a plurality of sub-pixel areas.

[0120] like Figure 6 and Figure 7 As shown, taking the first substrate 21 as a driving substrate as an example, the first substrate 21 includes a driving circuit layer 21a and a second electrode layer 21b, and the second electrode layer 21b includes a plurality of electrode blocks 21c located on a side of the driving circuit layer 21a close to the cholesteric liquid crystal layer 24.

[0121] Step S501 includes the following steps:

[0122] like Figure 6 As shown, a photoresist material is coated on the entire surface of the first substrate 21 having the second electrode layer 21 b to form a photoresist layer 27; and

[0123] like Figure 7 As shown, the photoresist layer 27 is exposed and developed to remove the photoresist material corresponding to each electrode block 21c, forming a barrier structure 23 having a plurality of pixel openings 23a. It can be understood that the barrier structure 23 is arranged around each pixel opening 23a, that is, around each sub-pixel area (26a, 26b, 26c).

[0124] S502: adding a liquid crystal composition into each pixel opening; the liquid crystal composition comprises a cholesteric liquid crystal and a polymerizable monomer; the polymerizable monomer comprises an anchoring group, a polymerizable group and an alignment group.

[0125] like Figure 8 As shown, the same liquid crystal composition is injected into each pixel opening 23 a , and the liquid crystal composition includes cholesteric liquid crystal 28 and polymerized monomer 29 . At this time, the pitch of the cholesteric liquid crystal 28 in each pixel opening 23 a is the same.

[0126] The cholesteric liquid crystal 28 in the liquid crystal composition is selected from the aforementioned light-controlled cholesteric liquid crystal or temperature-controlled cholesteric liquid crystal, which can simplify the liquid crystal injection process.

[0127] In some embodiments, the content (mass fraction) of the polymerized monomer 29 in the liquid crystal composition is 0.3% to 5%. By controlling the amount of the polymerized monomer 29 added, negative effects on the cholesteric liquid crystal 28 can be avoided.

[0128] In a specific embodiment, the added content of the polymerizable monomer 29 in the liquid crystal composition is 0.3%, 0.5%, 0.8%, 1%, 2%, 3%, 4% or 5%, but is not limited thereto.

[0129] Specifically, the description of the polymerizable monomer 29 can refer to the aforementioned embodiment, which will not be repeated here.

[0130] S503: Disposing a second substrate on a side of the retaining wall structure away from the first substrate to form a liquid crystal cell; at least a side of the second substrate close to the first substrate has a polar functional group.

[0131] like Fig. 9 As shown, the second substrate 22 is arranged in a box with the first substrate 21, and the second substrate 22 includes a substrate layer 22a and a first electrode layer 22b, the first electrode layer 22b entirely covers a side of the substrate layer 22a close to the cholesteric liquid crystal layer 24, and the retaining wall structure 23 is arranged close to the first electrode layer 22b on a side away from the first substrate 21.

[0132] Specifically, the first substrate 21 and / or the second substrate 22 need to be cleaned before being formed into a box, and the cleaning process must include an ultraviolet irradiation (EUV) process, which can modify the surface of the electrode layer (e.g., ITO layer) on the first substrate 21 and / or the second substrate 22, so that polar functional groups (e.g., hydroxyl groups) are generated on the corresponding electrode layer. When the surface of the electrode layer carries polar functional groups, the anchoring groups on the polymerized monomer 29 can be anchored to the substrate surface (i.e., the surface of the electrode layer), so that the formed self-aligned polymer is tightly combined with the corresponding substrate surface, thereby making the formed alignment encapsulation layer 25 fixedly connected to the target substrate.

[0133] S504: Control the polymerized monomers in the liquid crystal composition to undergo a polymerization reaction at least on the surface of the second substrate to form an alignment encapsulation layer; the alignment encapsulation layer includes a plurality of first alignment encapsulation units arranged one by one with the plurality of sub-pixel regions, and within the sub-pixel region, the first alignment encapsulation units are located on the surface of the second substrate and connected to the adjacent retaining wall structure.

[0134] Specifically, the steps of forming the alignment encapsulation layer include:

[0135] The entire surface of the liquid crystal box is illuminated so that the polymerizable monomers in the liquid crystal composition undergo a polymerization reaction at least on the surface of the second substrate to form an alignment encapsulation layer.

[0136] like Fig.10 and Fig.11As shown, UV light can be used to illuminate the entire surface of the liquid crystal box from the side of the second substrate 22 away from the first substrate 21. In the process of illuminating the entire surface of the liquid crystal box, the polymerized monomer 29 moves at least toward the second substrate 22, and is anchored and connected to the surface of the second substrate 22 (i.e., the surface of the first electrode layer 22b exposed in the sub-pixel area 26) through the hydroxyl group in the anchoring group. At the same time, the carbon-carbon double bond in the polymerized monomer 29 is opened and a polymerization reaction (such as a cross-linking reaction) occurs, thereby forming a self-aligned polymer on the surface of the target substrate, forming an alignment encapsulation layer 25.

[0137] It can be understood that the alignment packaging layer 25 can be formed at the position where the first electrode layer 22b on the second substrate 22 is exposed by the sub-pixel area 26. Since the retaining wall structure 23 is arranged close to the first electrode layer 22b on the side away from the first substrate 21 (for example, it is arranged in contact with the first electrode layer 22b), the edge of the alignment packaging layer 25 formed on the first electrode layer 22b will contact the adjacent retaining wall structure 23, thereby achieving connection, thereby realizing the function of encapsulating the cholesteric liquid crystal 28 in the sub-pixel area 26.

[0138] As mentioned above, the retaining wall structure 23 is arranged in close contact with the first electrode layer 22b, but is not fixedly connected. Under the action of external force, a gap is likely to appear between the retaining wall structure 23 and the first electrode layer 22b, thereby causing cross-color. The present application connects the first electrode layer 22b and the retaining wall structure 23 through an alignment packaging layer 25, which can effectively prevent the occurrence of cross-color problems.

[0139] Specifically, the description of the process of combining the polymerized monomer 29 with the target substrate to form the alignment encapsulation layer 25 can refer to the aforementioned embodiment, which will not be repeated here.

[0140] S505: adjusting the pitch of the cholesteric liquid crystal in different pixel openings to form a cholesteric liquid crystal layer.

[0141] The structural schematic diagram of the manufactured reflective display panel 20 is shown in FIG. Figure 3 shown.

[0142] The cholesteric liquid crystal includes light-controlled cholesteric liquid crystal or temperature-controlled cholesteric liquid crystal. The steps of forming the cholesteric liquid crystal layer include:

[0143] The cholesteric liquid crystals in different pixel openings 23a (ie, sub-pixel regions 26) are illuminated with different integrated light amounts or heated at different temperatures, so that the cholesteric liquid crystals in different pixel openings 23a have different helical pitches.

[0144] It is understandable that the pitch of the cholesteric liquid crystal layer 24 in the same sub-pixel area 26 is the same, and the pitch of the cholesteric liquid crystal layer 24 in different sub-pixel areas 26 is different, so that different colors can be reflected to achieve full-color display. The size of the preset pitch can be set according to actual needs.

[0145] As described in the previous embodiment, Fig.12 or Fig.13 As shown, when the material of the cholesteric liquid crystal layer 24 is selected from the light-controlled cholesteric liquid crystal 28, taking the first sub-pixel area 26a, the second sub-pixel and the third sub-pixel area 26c reflecting different colors as an example, UV light can be used to illuminate the three sub-pixel areas 26 with different amounts of light through a halftone mask 30 or an LDI method, so that the light-controlled cholesteric liquid crystals 28 located in the three sub-pixel areas 26 receive different amounts of integrated light, and finally the light-controlled cholesteric liquid crystals 28 in the three sub-pixel areas 26 have different pitches, thereby achieving full-color display.

[0146] like Fig.13 As shown, when the material of the cholesteric liquid crystal layer 24 is selected from the temperature-controlled cholesteric liquid crystal 28, taking the first sub-pixel area 26a, the second sub-pixel and the third sub-pixel area 26c reflecting different colors as an example, IR light can be used to irradiate the liquid crystal box. Specifically, the three different sub-pixel areas 26 can be illuminated using the LDI method. By controlling the illumination time, the temperature sensed by the cholesteric liquid crystal 28 is changed, so that the temperature of the cholesteric liquid crystal 28 located in different sub-pixel areas 26 is different, thereby making the pitch of the cholesteric liquid crystal 28 in different sub-pixel areas 26 different, thereby achieving different reflected colors.

[0147] like Fig.13 As shown, the embodiment of the present application preferably adopts the LDI method to illuminate the three different sub-pixel areas 26, so that the pitch of the cholesteric liquid crystal 28 in different sub-pixel areas 26 is different, thereby achieving different reflection colors, saving masks, and realizing mask-free pixel-level illumination, which is beneficial to saving production costs while improving display effects.

[0148] In the embodiment of the present application, only two illumination processes are required to form the alignment encapsulation layer 25 and the cholesteric liquid crystal layer 24 with different pitches, respectively. The preparation method is simple and easy to implement, which can effectively reduce the manufacturing process of the reflective display panel 20 and realize the reflective color display of a single panel. In addition, the alignment encapsulation layer 25 can be used to encapsulate the cholesteric liquid crystal layer 24 to prevent cross-coloring, and the cholesteric liquid crystal layer 24 can also be aligned to improve the display effect.

[0149] The embodiment of the present application further provides a reflective display device, comprising the reflective display panel 20 described in the above embodiment.

[0150] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0151] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0152] The embodiments, implementation methods and related technical features of the present application can be combined and replaced with each other without conflict.

[0153] The above are only preferred embodiments of the present application and do not constitute any form of limitation to the present application. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application are still within the scope of the technical solution of the present application.

Claims

1. A reflective display panel, characterized in that: include: A first substrate and a second substrate arranged opposite to each other; A retaining wall structure, located between the first substrate and the second substrate; The retaining wall structure is arranged on a surface of the first substrate on a side close to the second substrate, and the retaining wall structure divides the space between the first substrate and the second substrate into a plurality of sub-pixel regions arranged in the same layer, and the retaining wall structure is arranged around each of the sub-pixel regions; A cholesteric liquid crystal layer, located in the sub-pixel region; as well as An alignment encapsulation layer is at least located on a surface of the second substrate on a side close to the cholesteric liquid crystal layer; The alignment packaging layer includes a plurality of first alignment packaging units aligned with the plurality of sub-pixel regions. In the sub-pixel regions, the first alignment packaging units are located on the surface of the second substrate and connected to the adjacent retaining wall structures.

2. The reflective display panel according to claim 1, characterized in that: The side of the retaining wall structure close to the second substrate is arranged in contact with the surface of the second substrate; or The retaining wall structure is spaced apart from a side of the second substrate close to the second substrate, and the first alignment packaging unit is connected between the spaced apart retaining wall structure and the second substrate.

3. The reflective display panel according to claim 1 or 2, characterized in that: The second substrate comprises a substrate layer and a first electrode layer, wherein the first electrode layer entirely covers a side of the substrate layer close to the cholesteric liquid crystal layer; The retaining wall structure is disposed on a surface of the first substrate close to the first electrode layer, and the first alignment encapsulation unit is disposed on a surface of the first electrode layer close to the cholesteric liquid crystal layer and connected to the adjacent retaining wall structure.

4. The reflective display panel according to claim 1 or 2, characterized in that: The alignment encapsulation layer is also located on the surface of the first substrate on the side close to the cholesteric liquid crystal layer, and the alignment encapsulation layer also includes a plurality of second alignment encapsulation units arranged one by one with the plurality of sub-pixel regions; In the sub-pixel region, the second alignment packaging unit is located on a surface of the first substrate and is connected to the adjacent retaining wall structure.

5. The reflective display panel according to claim 4, characterized in that: The first substrate comprises a driving circuit layer and a second electrode layer electrically connected to each other, the second electrode layer comprises a plurality of electrode blocks located on a side of the driving circuit layer close to the cholesteric liquid crystal layer, the plurality of electrode blocks are arranged one by one with the plurality of sub-pixel regions; the retaining wall structure is located between any two adjacent electrode blocks; The second alignment encapsulation unit is disposed on a side of the electrode block close to the cholesteric liquid crystal layer and is connected to the adjacent retaining wall structure.

6. The reflective display panel according to claim 1, characterized in that: The material of the alignment encapsulation layer includes a self-alignment polymer, the self-alignment polymer includes an alignment group, and the alignment group includes a chain group composed of a plurality of cyclic groups.

7. The reflective display panel according to claim 1, characterized in that: The material of the cholesteric liquid crystal layer includes light-controlled cholesteric liquid crystal or temperature-controlled cholesteric liquid crystal; The multiple sub-pixel areas include multiple first sub-pixel areas and multiple second sub-pixel areas, the material of the cholesteric liquid crystal layer located in the first sub-pixel area and the second sub-pixel area is the same, and the pitch of the cholesteric liquid crystal layer located in the first sub-pixel area is different from the pitch of the cholesteric liquid crystal layer located in the second sub-pixel area.

8. A method for preparing a reflective display panel, characterized in that: The preparation method comprises the following steps: A retaining wall structure is formed on one side of the first substrate; the retaining wall structure is provided with a plurality of pixel openings exposing the first substrate, and the plurality of pixel openings divide a plurality of sub-pixel areas; Adding a liquid crystal composition into each of the pixel openings; the liquid crystal composition comprises a cholesteric liquid crystal and a polymerizable monomer; the polymerizable monomer comprises an anchoring group, a polymerizable group and an alignment group; A second substrate is arranged on a side of the retaining wall structure away from the first substrate to form a liquid crystal box; at least a side of the second substrate close to the first substrate has a polar functional group; Controlling the polymerizable monomers in the liquid crystal composition to undergo a polymerization reaction at least on the surface of the second substrate to form an alignment encapsulation layer; the alignment encapsulation layer comprises a first alignment encapsulation unit arranged one by one with the plurality of sub-pixel regions, wherein within the sub-pixel region, the first alignment encapsulation unit is located on the surface of the second substrate and connected to the adjacent retaining wall structure; and The pitches of the cholesteric liquid crystals in different pixel openings are adjusted to form a cholesteric liquid crystal layer.

9. The method for preparing a reflective display panel according to claim 8, characterized in that: The chemical structural formula of the polymerizable monomer is shown in Formula I: Wherein, A represents the anchoring group, B and C represent the polymerizable groups, and D represents the alignment group; the anchoring group contains at least one hydroxyl group, the polymerizable group contains at least one carbon-carbon double bond, and the alignment group contains a chain group composed of multiple cyclic groups.

10. The method for preparing a reflective display panel according to claim 8 or 9, characterized in that: The cholesteric liquid crystal includes light-controlled cholesteric liquid crystal or temperature-controlled cholesteric liquid crystal; The step of forming the alignment encapsulation layer comprises: Illuminating the entire surface of the liquid crystal box so that the polymerizable monomers in the liquid crystal composition undergo a polymerization reaction at least on the surface of the second substrate to form the alignment encapsulation layer; The steps of forming the cholesteric liquid crystal layer include: The cholesteric liquid crystals in different pixel openings are subjected to illumination treatments with different integrated light amounts or heating treatments with different temperatures, so that the cholesteric liquid crystals in different pixel openings have different helical pitches.

Images