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CN116009316A - Brightness enhancement film and its preparation method, display substrate and display device - Google Patents

Brightness enhancement film and its preparation method, display substrate and display device Download PDF

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CN116009316A
CN116009316A CN202310101067.3A CN202310101067A CN116009316A CN 116009316 A CN116009316 A CN 116009316A CN 202310101067 A CN202310101067 A CN 202310101067A CN 116009316 A CN116009316 A CN 116009316A
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light
layer
liquid crystal
microstructure
brightness enhancement
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谭明丰
张晓晋
孙海雁
张帅峰
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BOE Technology Group Co Ltd
Chengdu BOE Optoelectronics Technology Co Ltd
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BOE Technology Group Co Ltd
Chengdu BOE Optoelectronics Technology Co Ltd
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Abstract

本申请提供一种增亮膜及其制备方法、显示基板和显示装置,所述增亮膜包括含有液晶的微结构层,所述微结构层中包含多个微结构,所述微结构中包含所述液晶。在增亮膜中设置含有液晶的微结构层,微结构层中的多个微结构流动性较弱,对微结构内的液晶起到了稳定和限流的作用,使得增亮膜的折叠区和非折叠区内的液晶差别不大,故即使在增亮膜进行折弯的情况下,增亮膜的出光效率及折弯性能也能得到增强。将所述增亮膜应用于显示基板时,显示基板的出光效率得到提升,同时由于增亮膜中的微结构不易流动和稳定性好,显示基板的弯折性能得到提升,色偏得到改善。

Figure 202310101067

The present application provides a brightness enhancement film and its preparation method, a display substrate and a display device. The brightness enhancement film includes a microstructure layer containing liquid crystals, the microstructure layer contains a plurality of microstructures, and the microstructure contains The liquid crystal. A microstructure layer containing liquid crystals is set in the brightness enhancement film, and the fluidity of multiple microstructures in the microstructure layer is weak, which plays a role in stabilizing and limiting the flow of liquid crystals in the microstructure, so that the folding area of the brightness enhancement film and There is little difference in the liquid crystals in the non-folding region, so even when the brightness enhancing film is bent, the light extraction efficiency and bending performance of the brightness enhancing film can be enhanced. When the brightness enhancement film is applied to a display substrate, the light extraction efficiency of the display substrate is improved, and at the same time, because the microstructure in the brightness enhancement film is not easy to flow and has good stability, the bending performance of the display substrate is improved and the color shift is improved.

Figure 202310101067

Description

增亮膜及其制备方法、显示基板和显示装置Brightness enhancement film and preparation method thereof, display substrate and display device

技术领域Technical Field

本申请涉及显示技术领域,尤其涉及一种增亮膜及其制备方法、显示基板和显示装置。The present application relates to the field of display technology, and in particular to a brightness enhancement film and a preparation method thereof, a display substrate and a display device.

背景技术Background Art

有机发光二极管(Organic light-emitting diode,简称OLED)由于其色彩饱和度高、可视角宽、可折叠等优点而被广泛应用于显示屏中。现今,研究者致力于开发新的材料体系以提高OLED的出光效率和降低功耗,从而达到提高亮度和省电的要求。Organic light-emitting diodes (OLEDs) are widely used in display screens due to their high color saturation, wide viewing angle, and foldability. Today, researchers are committed to developing new material systems to improve the light extraction efficiency of OLEDs and reduce power consumption, thereby achieving the requirements of increasing brightness and saving power.

发明内容Summary of the invention

有鉴于此,本申请的目的在于提出一种增亮膜及其制备方法、显示基板和显示装置。In view of this, the purpose of the present application is to provide a brightness enhancement film and a preparation method thereof, a display substrate and a display device.

基于上述目的,本申请第一方面提供了一种增亮膜,包括:含有液晶的微结构层,所述微结构层中包含多个微结构,所述微结构中包含液晶。Based on the above purpose, the first aspect of the present application provides a brightness enhancement film, comprising: a microstructure layer containing liquid crystal, wherein the microstructure layer comprises a plurality of microstructures, and the microstructures comprise liquid crystals.

进一步地,所述微结构为微胶囊。Furthermore, the microstructure is a microcapsule.

进一步地,所述液晶为胆甾相液晶。Furthermore, the liquid crystal is cholesteric liquid crystal.

进一步地,所述微结构层包括多层叠置的微结构子层,每个所述微结构子层的反射波段不同。Furthermore, the microstructure layer includes a plurality of stacked microstructure sublayers, and each of the microstructure sublayers has a different reflection band.

进一步地,所述微结构层的厚度为10~60μm。Furthermore, the thickness of the microstructure layer is 10 to 60 μm.

进一步地,所述微结构子层的厚度为1~10μm。Furthermore, the thickness of the microstructure sublayer is 1-10 μm.

进一步地,所述微结构层和所述微结构子层的雾度均小于或等于3%。Furthermore, the haze of the microstructure layer and the microstructure sublayer is less than or equal to 3%.

进一步地,所述微结构层由含有液晶的微结构、聚合物单体和光引发剂的混合物制成。Furthermore, the microstructure layer is made of a mixture of microstructures containing liquid crystals, polymer monomers and photoinitiators.

进一步地,所述含有液晶的微结构为含有胆甾相液晶的微胶囊,所述微胶囊包括芯材料和包裹于所述芯材料外部的壳材料,所述芯材料包含以下重量份数的组分:65%~85%的向列相液晶、10%~30%的左旋或右旋的胆甾相液晶、4%~5%的手性添加剂。Furthermore, the liquid crystal-containing microstructure is a microcapsule containing cholesteric liquid crystal, the microcapsule includes a core material and a shell material wrapped around the core material, and the core material contains the following components in weight proportions: 65% to 85% of nematic liquid crystal, 10% to 30% of left-handed or right-handed cholesteric liquid crystal, and 4% to 5% of a chiral additive.

本申请第二方面提供了一种显示基板,包括:A second aspect of the present application provides a display substrate, comprising:

基底,包括折叠区和非折叠区;A substrate, including a folded region and a non-folded region;

发光结构层,设置于所述基底上;A light-emitting structure layer is disposed on the substrate;

上述第一方面任一项所述的增亮膜,设置于所述发光结构层远离所述基底的一侧,所述增亮膜在所述基底上的正投影至少覆盖所述折叠区;The brightness enhancement film described in any one of the first aspects above is arranged on a side of the light-emitting structure layer away from the substrate, and the orthographic projection of the brightness enhancement film on the substrate at least covers the folding area;

防反射层,设置于所述增亮膜远离所述基底的一侧。The anti-reflection layer is arranged on a side of the brightness enhancement film away from the substrate.

进一步地,所述发光结构层包括被像素定义层限定的多个像素开口所形成的多个发光区,多个发光区包括发出第一颜色光的第一发光区、发出第二颜色光的第二发光区和发出第三颜色光的第三发光区;Further, the light emitting structure layer includes a plurality of light emitting areas formed by a plurality of pixel openings defined by the pixel definition layer, the plurality of light emitting areas including a first light emitting area emitting a first color light, a second light emitting area emitting a second color light, and a third light emitting area emitting a third color light;

所述微结构层包括依次叠置的三层微结构子层,所述三层微结构子层的反射波段与所述第一颜色光的波长、第二颜色光的波长和第三颜色光的波长一一对应。The microstructure layer includes three microstructure sublayers stacked in sequence, and the reflection bands of the three microstructure sublayers correspond one-to-one to the wavelength of the first color light, the wavelength of the second color light, and the wavelength of the third color light.

进一步地,所述发光结构层包括被像素定义层限定的多个像素开口所形成的多个发光区,多个发光区包括发出第一颜色光的第一发光区、发出第二颜色光的第二发光区和发出第三颜色光的第三发光区;Further, the light emitting structure layer includes a plurality of light emitting areas formed by a plurality of pixel openings defined by the pixel definition layer, the plurality of light emitting areas including a first light emitting area emitting a first color light, a second light emitting area emitting a second color light, and a third light emitting area emitting a third color light;

所述微结构层为单层微结构子层,所述微结构子层的反射波段与所述第一颜色光的波长、第二颜色光的波长或第三颜色光的波长对应。The microstructure layer is a single-layer microstructure sublayer, and a reflection band of the microstructure sublayer corresponds to the wavelength of the first color light, the wavelength of the second color light, or the wavelength of the third color light.

本申请第三方面提供了一种增亮膜的制备方法,包括:The third aspect of the present application provides a method for preparing a brightness enhancement film, comprising:

将含有液晶的微结构、聚合物单体和光引发剂混合,形成混合体系;Mixing a microstructure containing liquid crystal, a polymer monomer and a photoinitiator to form a mixed system;

将混合体系铺展,使其形成混合体系预制膜层,通过光照射混合体系预制膜层,使混合体系中的光引发剂引发聚合物单体发生聚合反应,得到增亮膜。The mixed system is spread to form a mixed system prefabricated film layer, and the mixed system prefabricated film layer is irradiated with light so that the photoinitiator in the mixed system triggers the polymer monomer to undergo a polymerization reaction to obtain a brightness enhancement film.

进一步地,所述将混合体系铺展,使其形成混合体系预制膜层,包括:Furthermore, spreading the mixed system to form a mixed system prefabricated membrane layer comprises:

将所述混合体系铺展在基板的表面,所述基板的表面形成所述混合体系预制膜层;或,将所述混合体系装入透明盒状体中,使所述混合体系铺展于透明盒状体中,所述混合体系预制膜层形成在所述透明盒状体中。The mixed system is spread on the surface of a substrate, and a prefabricated film layer of the mixed system is formed on the surface of the substrate; or, the mixed system is loaded into a transparent box-shaped body, and the mixed system is spread in the transparent box-shaped body, and the prefabricated film layer of the mixed system is formed in the transparent box-shaped body.

本申请第四方面提供了一种显示装置,包括上述第二方面任一项所述的显示基板,所述显示基板为有机发光二极管显示基板。A fourth aspect of the present application provides a display device, comprising the display substrate described in any one of the second aspects above, wherein the display substrate is an organic light emitting diode display substrate.

从上面所述可以看出,本申请提供的增亮膜及其制备方法、显示基板和显示装置,在增亮膜中设置含有液晶的微结构层,微结构层中的多个微结构流动性较差,对微结构内的液晶起到了稳定和限流的作用,避免微结构层内的液晶随意流动,导致微结构层内的液晶分布不均匀,进而导致增亮膜的出光强度及出光效率降低。即使在增亮膜进行弯折的情况下,由于微结构流动性较差,使得增亮膜的弯折区和非弯折区内的液晶分布差别不大,避免出现色偏的问题,提升增亮膜的出光效率及折弯性能。将所述增亮膜应用于显示基板时,增亮膜可以提升显示基板的出光效率,同时由于增亮膜中的微结构不易流动,稳定性好,可以避免出现因液晶流动造成的显示基板折叠区和非折叠区的液晶分布不均匀导致的光透过率不同的问题,有效提升显示基板的出光效率及弯折性能,同时还可以改善色偏。From the above, it can be seen that the brightness enhancement film and its preparation method, display substrate and display device provided by the present application are provided with a microstructure layer containing liquid crystal in the brightness enhancement film, and the multiple microstructures in the microstructure layer have poor fluidity, which plays a role in stabilizing and limiting the current of the liquid crystal in the microstructure, avoiding the liquid crystal in the microstructure layer from flowing randomly, resulting in uneven distribution of liquid crystal in the microstructure layer, and then causing the light output intensity and light output efficiency of the brightness enhancement film to decrease. Even in the case where the brightness enhancement film is bent, due to the poor fluidity of the microstructure, the distribution of liquid crystal in the bending area and the non-bending area of the brightness enhancement film is not much different, avoiding the problem of color deviation, and improving the light output efficiency and bending performance of the brightness enhancement film. When the brightness enhancement film is applied to the display substrate, the brightness enhancement film can improve the light output efficiency of the display substrate. At the same time, since the microstructure in the brightness enhancement film is not easy to flow and has good stability, it can avoid the problem of different light transmittance caused by uneven distribution of liquid crystal in the folding area and non-folding area of the display substrate caused by the flow of liquid crystal, effectively improving the light output efficiency and bending performance of the display substrate, and at the same time, it can also improve color deviation.

附图说明BRIEF DESCRIPTION OF THE DRAWINGS

为了更清楚地说明本申请或相关技术中的技术方案,下面将对实施例或相关技术描述中所需要使用的附图作简单地介绍,显而易见地,下面描述中的附图仅仅是本申请的实施例,对于本领域普通技术人员来讲,在不付出创造性劳动的前提下,还可以根据这些附图获得其他的附图。In order to more clearly illustrate the technical solutions in the present application or related technologies, the drawings required for use in the embodiments or related technical descriptions are briefly introduced below. Obviously, the drawings described below are merely embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

图1为相关技术中在显示面板中设置防反射膜的示意图;FIG1 is a schematic diagram of providing an anti-reflection film in a display panel in the related art;

图2为相关技术中在显示面板中设置防反射膜和液晶功能层的示意图;FIG2 is a schematic diagram of providing an anti-reflection film and a liquid crystal functional layer in a display panel in the related art;

图3为相关技术中的折叠显示装置的示例性结构示意图;FIG3 is a schematic diagram of an exemplary structure of a foldable display device in the related art;

图4为本申请实施例的增亮膜的结构示意图;FIG4 is a schematic structural diagram of a brightness enhancement film according to an embodiment of the present application;

图5为本申请实施例的增亮膜的微结构层具有多个微结构子层的示意图;FIG5 is a schematic diagram of a brightness enhancement film according to an embodiment of the present application having a microstructure layer with multiple microstructure sublayers;

图6为本申请施例的显示基板的第一种结构示意图;FIG6 is a schematic diagram of a first structure of a display substrate according to an embodiment of the present application;

图7为本申请施例的显示基板的第二种结构示意图;FIG7 is a schematic diagram of a second structure of a display substrate according to an embodiment of the present application;

图8为本申请施例的增亮膜的制备方法的流程图;FIG8 is a flow chart of a method for preparing a brightness enhancement film according to an embodiment of the present application;

图9为本申请实施例的增亮膜分为弯折区和非弯折区的结构示意图。FIG. 9 is a schematic structural diagram of a brightness enhancement film according to an embodiment of the present application, which is divided into a bending area and a non-bending area.

图中,100、机壳;101、铰链组件;102、平整区;2、柔性显示模组;201、柔性基底;202、发光层;203、液晶层;204、防反射膜层;205、折叠区;In the figure, 100, housing; 101, hinge assembly; 102, flat area; 2, flexible display module; 201, flexible substrate; 202, light-emitting layer; 203, liquid crystal layer; 204, anti-reflection film layer; 205, folding area;

1、基底;2、发光结构层;3、增亮膜;31、微结构子层;32、弯折区;33、非弯折区;4、防反射层;5、驱动电路层;6、封装结构层;7、触控层。1. Substrate; 2. Light-emitting structure layer; 3. Brightness enhancement film; 31. Microstructure sublayer; 32. Bending area; 33. Non-bending area; 4. Anti-reflection layer; 5. Driving circuit layer; 6. Packaging structure layer; 7. Touch layer.

具体实施方式DETAILED DESCRIPTION

为使本申请的目的、技术方案和优点更加清楚明白,以下结合具体实施例,并参照附图,对本申请进一步详细说明。In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

需要说明的是,除非另外定义,本申请实施例使用的技术术语或者科学术语应当为本申请所属领域内具有一般技能的人士所理解的通常意义。本申请实施例中使用的“第一”、“第二”以及类似的词语并不表示任何顺序、数量或者重要性,而只是用来区分不同的组成部分。“包括”或者“包含”等类似的词语意指出现该词前面的元件或者物件涵盖出现在该词后面列举的元件或者物件及其等同,而不排除其他元件或者物件。“连接”或者“相连”等类似的词语并非限定于物理的或者机械的连接,而是可以包括电性的连接,不管是直接的还是间接的。“上”、“下”、“左”、“右”等仅用于表示相对位置关系,当被描述对象的绝对位置改变后,则该相对位置关系也可能相应地改变。It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present application should be the usual meanings understood by people with ordinary skills in the field to which the present application belongs. The "first", "second" and similar words used in the embodiments of the present application do not represent any order, quantity or importance, but are only used to distinguish different components. "Including" or "comprising" and similar words mean that the elements or objects appearing in front of the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

OLED器件是一种有机薄膜电致发光器件,其具有制备工艺简单、成本低、功耗低、发光亮度高、工作温度适应范围广、体积轻薄、响应速度快、易形成柔性结构、视角宽等优点,因此,利用有机发光二极管的显示技术已成为一种重要的显示技术。OLED devices are an organic thin film electroluminescent device, which has the advantages of simple preparation process, low cost, low power consumption, high luminous brightness, wide operating temperature adaptability range, light volume, fast response speed, easy to form a flexible structure, wide viewing angle, etc. Therefore, the display technology using organic light emitting diodes has become an important display technology.

OLED器件包括:阴极、有机功能层和阳极,其中,电极(阴极和阳极)一般采用金属或者金属合金形成。然而,金属或者金属合金对于外界光线的反射率较高,当有机功能层发出的光经阴极发出时,人眼获得的OLED器件的显示亮度为原本要显示的亮度与反射的外界光线的亮度之和,即OLED器件的显示亮度发生了偏差,从而影响了OLED器件的显示效果。OLED devices include: cathode, organic functional layer and anode, wherein the electrodes (cathode and anode) are generally formed of metal or metal alloy. However, metal or metal alloy has a high reflectivity to external light. When the light emitted by the organic functional layer is emitted through the cathode, the display brightness of the OLED device obtained by the human eye is the sum of the original brightness to be displayed and the brightness of the reflected external light, that is, the display brightness of the OLED device is deviated, thereby affecting the display effect of the OLED device.

相关技术中通过在显示面板中设置防反射膜来解决这一问题。参考图1,防反射膜由线偏振片和1/4λ波片组成,其中1/4λ波片设置在阴极远离有机功能层的一侧,线偏振片设置在1/4λ波片远离阴极的一侧。In the related art, this problem is solved by setting an anti-reflection film in the display panel. Referring to FIG1 , the anti-reflection film is composed of a linear polarizer and a 1/4λ wave plate, wherein the 1/4λ wave plate is set on the side of the cathode away from the organic functional layer, and the linear polarizer is set on the side of the 1/4λ wave plate away from the cathode.

当外界自然光线经过线偏振片后,外界光线中与线偏振片的透过轴相平行的光透过、与线偏振片的透过轴相垂直的光被吸收,即外界光线经过线偏振片后转变成偏振方向与线偏振片的透过轴相平行的线偏振光。线偏振光继续经过1/4λ波片,1/4λ波片将线偏光转变为左旋或右旋的圆偏振光,经过金属电极反射后转变为旋向相反的右旋或者左旋的圆偏振光,再次经过1/4λ波片后的线偏振光其偏振方向与线偏振片的透过轴相垂直,因此该线偏振光被线偏振片吸收,不能透过线偏振片,故防反射膜解决了环境光经由电极反射而引起的在明视场下对比度下降的问题。When the external natural light passes through the linear polarizer, the light parallel to the transmission axis of the linear polarizer is transmitted, and the light perpendicular to the transmission axis of the linear polarizer is absorbed, that is, the external light is converted into linear polarized light with the polarization direction parallel to the transmission axis of the linear polarizer after passing through the linear polarizer. The linear polarized light continues to pass through the 1/4λ wave plate, which converts the linear polarized light into left-handed or right-handed circular polarized light, which is then converted into right-handed or left-handed circular polarized light with the opposite rotation direction after being reflected by the metal electrode. The polarization direction of the linear polarized light after passing through the 1/4λ wave plate again is perpendicular to the transmission axis of the linear polarizer, so the linear polarized light is absorbed by the linear polarizer and cannot pass through the linear polarizer. Therefore, the anti-reflection film solves the problem of contrast reduction in bright field caused by ambient light reflected by the electrode.

但是,OLED器件的有机功能层发出的光为自然光,其经过线偏振片后,只有与线偏振片的偏振方向平行的光才可透过并用于显示,垂直的光则被吸收。因此,OLED器件的有机发光层发出的光通过现有的线偏振片后,其亮度至少会衰减一半,从而导致显示亮度明显降低。However, the light emitted by the organic functional layer of the OLED device is natural light. After passing through the linear polarizer, only the light parallel to the polarization direction of the linear polarizer can pass through and be used for display, while the perpendicular light is absorbed. Therefore, after the light emitted by the organic light-emitting layer of the OLED device passes through the existing linear polarizer, its brightness will be attenuated by at least half, resulting in a significant reduction in display brightness.

为了解决该问题,相关技术中提出封装层上彩膜(COE)技术和圆偏振技术。封装层上彩膜技术取消了防反射膜,重新引入了彩膜,但这将导致制造工艺复杂,视角色偏提高。圆偏振技术保留了防反射膜,在反射膜与阴极之间添加了液晶功能层(例如胆甾相液晶功能层),采用液晶功能层和防反射膜的配合来解决显示亮度降低的问题。相较于封装层上彩膜技术,圆偏振技术工艺简单,成本更低,并且在显示效果方面,视角色偏更小,因此其具有能被量产应用的潜在价值。In order to solve this problem, the related art proposes the color film on encapsulation layer (COE) technology and the circular polarization technology. The color film on encapsulation layer technology cancels the anti-reflection film and reintroduces the color film, but this will lead to a complicated manufacturing process and increased visual color deviation. The circular polarization technology retains the anti-reflection film, adds a liquid crystal functional layer (such as a cholesteric liquid crystal functional layer) between the reflective film and the cathode, and uses the liquid crystal functional layer and the anti-reflection film to solve the problem of reduced display brightness. Compared with the color film on encapsulation layer technology, the circular polarization technology has a simple process, lower cost, and smaller visual color deviation in terms of display effect, so it has the potential value of being able to be mass-produced and applied.

参考图2,圆偏振技术中引入了左旋或右旋的液晶功能层(这里以右旋为例说明)。有机发光层发出的自然光经过液晶功能层时被调制为左旋和右旋的圆偏振光。一方面,左旋圆偏振光经过λ/4波片后转变为偏振方向与线偏振片(即图2中的POL,此过程无吸收)的透过轴平行的光,该光经过线偏振片到达外界;另一方面,右旋偏振光被右旋液晶功能层反射到电极(即图2中的EL)上,并被电极反射为左旋圆偏振光,该左旋偏振光可以通过右旋液晶功能层,接着经过λ/4波片后转变为偏振方向与线偏振片的透过轴平行的光,该光经过线偏振片到达外界。相比现有技术,本发明通过在电极和λ/4波片之间增加了液晶功能层,使原本无法到达外界的有机功能层发出的光线重新被利用,从而极大增加了出光量,同时还可以保证对外界光具有较低的反射率,可以解决显示亮度降低的问题。Referring to FIG2 , a left-handed or right-handed liquid crystal functional layer is introduced into the circular polarization technology (here the right-handed one is used as an example). The natural light emitted by the organic light-emitting layer is modulated into left-handed and right-handed circularly polarized light when passing through the liquid crystal functional layer. On the one hand, the left-handed circularly polarized light is converted into light with a polarization direction parallel to the transmission axis of the linear polarizer (i.e., POL in FIG2 , and there is no absorption in this process) after passing through the λ/4 wave plate, and the light passes through the linear polarizer to reach the outside world; on the other hand, the right-handed polarized light is reflected by the right-handed liquid crystal functional layer to the electrode (i.e., EL in FIG2 ), and is reflected by the electrode as left-handed circularly polarized light, and the left-handed polarized light can pass through the right-handed liquid crystal functional layer, and then after passing through the λ/4 wave plate, it is converted into light with a polarization direction parallel to the transmission axis of the linear polarizer, and the light passes through the linear polarizer to reach the outside world. Compared with the prior art, the present invention adds a liquid crystal functional layer between the electrode and the λ/4 wave plate, so that the light emitted by the organic functional layer that could not reach the outside world can be reused, thereby greatly increasing the light output, while also ensuring a low reflectivity to the outside light, which can solve the problem of reduced display brightness.

虽然通过增加液晶功能层可以解决显示面板显示亮度降低的问题,但是,对于柔性(折叠或曲面)OLED显示面板来说,增加液晶功能层又带来了弯折性能下降的问题。参考图3,图3示出了相关技术中的折叠显示装置的示例性结构示意图,图3中的虚线部分表示折叠区205,柔性显示模组2背离显示面的侧面固定在显示装置的机壳100上,对于折叠显示,由于折叠区205进行折叠的展开与弯折动作,所以在机壳100上需要在折叠区205对应的位置设计铰链组件101,铰链组件101是一种铰接的活动机构,其可以实现弯折中的活动动作,机壳100的其他部分为平整区102。如图3所示,柔性显示模组2包括依次叠置的柔性基底201、发光层202和防反射膜层204(包括λ/4波片和线偏振片)。为了解决显示亮度降低的问题,相关技术中同样采取了在发光层202和防反射膜层204之间增加液晶层203的手段。但是,由于液晶层中的液晶流动性较强,在折叠或弯折时,折叠区205的液晶将会向周边流动,这将导致折叠区205和非折叠区的液晶分布不均匀,进而导致折叠区205和非折叠区的光透过率不同,导致色偏,进而导致显示面板的弯折性能较差。因此,如何同时提升显示面板的出光效率和弯折性能是亟需解决的问题。Although the problem of reduced display brightness of the display panel can be solved by adding a liquid crystal functional layer, for a flexible (folding or curved) OLED display panel, adding a liquid crystal functional layer brings about the problem of reduced bending performance. Referring to FIG3 , FIG3 shows an exemplary structural schematic diagram of a folding display device in the related art. The dotted line portion in FIG3 represents a folding area 205. The side of the flexible display module 2 facing away from the display surface is fixed on the housing 100 of the display device. For folding display, since the folding area 205 performs folding, unfolding and bending actions, a hinge assembly 101 needs to be designed at a position corresponding to the folding area 205 on the housing 100. The hinge assembly 101 is a hinged movable mechanism that can realize the movable action during bending. The other parts of the housing 100 are flat areas 102. As shown in FIG3 , the flexible display module 2 includes a flexible substrate 201, a light-emitting layer 202 and an anti-reflection film layer 204 (including a λ/4 wave plate and a linear polarizer) stacked in sequence. In order to solve the problem of reduced display brightness, the related art also adopts the means of adding a liquid crystal layer 203 between the light-emitting layer 202 and the anti-reflection film layer 204. However, due to the strong fluidity of the liquid crystal in the liquid crystal layer, when folded or bent, the liquid crystal in the folding area 205 will flow to the periphery, which will cause the liquid crystal in the folding area 205 and the non-folding area to be unevenly distributed, and then cause the light transmittance of the folding area 205 and the non-folding area to be different, resulting in color deviation, and then causing the bending performance of the display panel to be poor. Therefore, how to simultaneously improve the light extraction efficiency and bending performance of the display panel is an urgent problem to be solved.

基于以上问题,本申请提供了一种增亮膜及其制备方法、显示基板和显示装置,所述增亮膜包括含有液晶的微结构层,所述微结构层中包含多个微结构,所述微结构中包含所述液晶。在增亮膜中设置含有液晶的微结构层,微结构层中的多个微结构流动性较弱,对微结构内的液晶起到了稳定和限流的作用。由于微结构流动性较弱,故即使在增亮膜进行折弯的情况下,增亮膜的弯折区和非弯折区内的液晶分布差别不大,增亮膜的出光效率及折弯性能得到增强。将所述增亮膜应用于显示基板时,显示基板的出光效率得到提升,同时由于增亮膜中的微结构不易流动和稳定性好,显示基板的弯折性能得到提升,色偏得到改善。Based on the above problems, the present application provides a brightness enhancement film and a preparation method thereof, a display substrate and a display device, wherein the brightness enhancement film includes a microstructure layer containing liquid crystals, wherein the microstructure layer includes a plurality of microstructures, and wherein the microstructures include the liquid crystals. A microstructure layer containing liquid crystals is provided in the brightness enhancement film, and the plurality of microstructures in the microstructure layer have a relatively weak fluidity, which has a stabilizing and current limiting effect on the liquid crystals in the microstructures. Since the microstructure has a relatively weak fluidity, even when the brightness enhancement film is bent, the distribution of liquid crystals in the bending area and the non-bending area of the brightness enhancement film is not much different, and the light extraction efficiency and bending performance of the brightness enhancement film are enhanced. When the brightness enhancement film is applied to a display substrate, the light extraction efficiency of the display substrate is improved. At the same time, since the microstructures in the brightness enhancement film are not easy to flow and have good stability, the bending performance of the display substrate is improved, and the color deviation is improved.

以下结合具体实施例,并参照附图,对本申请进一步详细说明。The present application is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

参考图4,本申请第一方面提供了一种增亮膜3,包括:含有液晶的微结构层,所述微结构层中包含多个微结构,所述微结构中包含液晶。4 , the first aspect of the present application provides a brightness enhancement film 3 , comprising: a microstructure layer containing liquid crystal, wherein the microstructure layer comprises a plurality of microstructures, and the microstructures comprise liquid crystals.

具体地,所述液晶可以为胆甾相液晶,所述微结构可以为微胶囊。Specifically, the liquid crystal may be a cholesteric liquid crystal, and the microstructure may be a microcapsule.

胆甾相液晶(Cholesteric liquid crystal,CLC)是一维光子晶体,它区别于其他向列相或近晶相的液晶材料,胆甾相液晶分子呈扁平状,排列成层,层内分子相互平行,分子长轴平行于层平面,不同层的分子长轴方向稍有变化,沿层的法线方向排列成螺旋状结构。该螺旋状结构呈左旋或右旋。按照螺旋状结构的旋向可以将胆甾相液晶分为左旋胆甾相液晶和右旋胆甾相液晶。由于其独特的螺旋扭曲结构,其具有特殊的光学特性,如旋光性、选择性反射和圆二色性,具有不同螺距的胆甾相液晶具有不同的反射波段(也可称为反射窗口),因此其可以选择性的反射波长位于其反射波段内的光,而透过波长不在其反射波段的光,因此,可以分别制作出反射红光的胆甾相液晶、反射绿光的胆甾相液晶或反射蓝光的胆甾相液晶。胆甾相液晶圆二色性决定圆偏振光反射还是透射,也就是说,自然光经过右旋的胆甾相液晶,则透射出左旋圆偏振光,反射出右旋圆偏振光;自然光经过左旋的胆甾相液晶,则透射出右旋圆偏振光,反射出左旋圆偏振光。Cholesteric liquid crystal (CLC) is a one-dimensional photonic crystal. It is different from other nematic or smectic liquid crystal materials. Cholesteric liquid crystal molecules are flat and arranged in layers. The molecules in the layers are parallel to each other, and the molecular long axis is parallel to the layer plane. The direction of the molecular long axis of different layers is slightly changed, and they are arranged in a spiral structure along the normal direction of the layer. The spiral structure is left-handed or right-handed. According to the direction of the spiral structure, cholesteric liquid crystal can be divided into left-handed cholesteric liquid crystal and right-handed cholesteric liquid crystal. Due to its unique spiral twisted structure, it has special optical properties, such as optical activity, selective reflection and circular dichroism. Cholesteric liquid crystals with different pitches have different reflection bands (also called reflection windows), so it can selectively reflect light with a wavelength in its reflection band, and transmit light with a wavelength not in its reflection band. Therefore, cholesteric liquid crystals that reflect red light, cholesteric liquid crystals that reflect green light, or cholesteric liquid crystals that reflect blue light can be produced respectively. The circular dichroism of cholesteric liquid crystal determines whether circularly polarized light is reflected or transmitted. That is to say, when natural light passes through right-handed cholesteric liquid crystal, left-handed circularly polarized light is transmitted and right-handed circularly polarized light is reflected; when natural light passes through left-handed cholesteric liquid crystal, right-handed circularly polarized light is transmitted and left-handed circularly polarized light is reflected.

微胶囊是由天然或合成高分子制成的微型容器,由被包裹材料和包裹材料组成的,包于内部的材料一般称为芯材料,包裹材料通常称为壳材料。通常来说,壳材料可以是有机聚合物、水溶胶、糖、蜡、脂肪、金属或无极氧化物等。微胶囊为直径在1~20μm之间、具有核壳结构的微小粒子。微胶囊结构制备简单,便于工业化生产。Microcapsules are micro-containers made of natural or synthetic polymers, which are composed of the encapsulated material and the encapsulating material. The material encapsulated inside is generally called the core material, and the encapsulating material is usually called the shell material. Generally speaking, the shell material can be an organic polymer, hydrosol, sugar, wax, fat, metal or inorganic oxide, etc. Microcapsules are tiny particles with a diameter of 1 to 20 μm and a core-shell structure. The microcapsule structure is simple to prepare and is convenient for industrial production.

将胆甾相液晶制成胆甾相液晶微胶囊,一方面可以保留胆甾相液晶的特性,利用其特性来提升增亮膜3的出光强度和出光亮度,另一方面,将胆甾相液晶微胶囊化,微胶囊对其内部的胆甾相液晶起到了稳定和限流的作用,可以使液晶微胶囊的层厚度保持一致,防止微胶囊内的液晶随意流动导致增亮膜3内的液晶分布不均匀,进而导致增亮膜3的出光强度及出光效率降低。即使在增亮膜3进行折弯的情况下,由于微胶囊流动性较差,使得增亮膜3的弯折区和非弯折区内的液晶差别不大,避免出现色偏的问题,提升增亮膜3的出光效率及折弯性能。将所述增亮膜3应用于显示基板时,增亮膜3可以提升显示基板的出光效率,同时由于增亮膜3中的微结构不易流动,稳定性好,可以避免出现因液晶流动造成的显示基板折叠区和非折叠区的液晶分布不均匀导致的光透过率不同的问题,有效提升显示基板的弯折性能。The cholesteric liquid crystal is made into a cholesteric liquid crystal microcapsule. On the one hand, the characteristics of the cholesteric liquid crystal can be retained, and its characteristics can be used to improve the light output intensity and brightness of the brightness enhancement film 3. On the other hand, the cholesteric liquid crystal is microencapsulated, and the microcapsule plays a role in stabilizing and limiting the cholesteric liquid crystal inside it, so that the layer thickness of the liquid crystal microcapsule can be kept consistent, and the liquid crystal in the microcapsule is prevented from flowing randomly, resulting in uneven distribution of liquid crystal in the brightness enhancement film 3, which in turn leads to a decrease in the light output intensity and light output efficiency of the brightness enhancement film 3. Even in the case where the brightness enhancement film 3 is bent, due to the poor fluidity of the microcapsule, the liquid crystal in the bending area and the non-bending area of the brightness enhancement film 3 is not much different, avoiding the problem of color deviation, and improving the light output efficiency and bending performance of the brightness enhancement film 3. When the brightness enhancement film 3 is applied to a display substrate, the brightness enhancement film 3 can improve the light output efficiency of the display substrate. At the same time, because the microstructure in the brightness enhancement film 3 is not easy to flow and has good stability, it can avoid the problem of different light transmittance caused by uneven distribution of liquid crystal in the folding area and non-folding area of the display substrate caused by the flow of liquid crystal, and effectively improve the bending performance of the display substrate.

在一些实施例中,参考图5,所述微结构层包括多层叠置的微结构子层31,每个所述微结构子层31的反射波段不同。In some embodiments, referring to FIG. 5 , the microstructure layer includes a plurality of stacked microstructure sublayers 31 , and each of the microstructure sublayers 31 has a different reflection band.

具体地,每个所述微结构子层31的反射波段不同,使得每个微结构子层仅可以反射波长在其反射波段内的光,而透过其他波长不在其反射波段内的光。被反射的特定波长的光再次被反射后,其旋向发生改变,旋向发生改变的光可以继续透过微结构子层31,进而提升了该特定波长光的透过率,增强了其出光强度。Specifically, each of the microstructure sublayers 31 has a different reflection band, so that each microstructure sublayer can only reflect light with a wavelength within its reflection band, and transmit light with other wavelengths that are not within its reflection band. After the reflected light of a specific wavelength is reflected again, its handedness changes, and the light with changed handedness can continue to pass through the microstructure sublayer 31, thereby improving the transmittance of the light of the specific wavelength and enhancing its light output intensity.

通过设置反射波段不同的多层叠置的微结构子层31可以反射各种波长的光,各种波长的光再次被反射后均可以从微结构子层31中射出,提升具有不同波长的各种颜色的光(例如红光、绿光和蓝光)的透过率,进而提升白光的出光效率。By setting up a multi-layer stacked microstructure sublayer 31 with different reflection bands, light of various wavelengths can be reflected. After being reflected again, light of various wavelengths can be emitted from the microstructure sublayer 31, thereby improving the transmittance of various colors of light with different wavelengths (such as red light, green light and blue light), thereby improving the light extraction efficiency of white light.

在一些实施例中,所述微结构层为单层的微结构子层31。In some embodiments, the microstructure layer is a single-layer microstructure sublayer 31 .

具体地,实际使用时,可以根据需要设置单层的微结构子层31,该单层的微结构子层31具有特定的反射波段,其可以选择性的反射波长位于其反射波段内的光,而透过波长不在其反射波段的光,因此,仅设置一层微结构子层31,可以专门用于反射特定波长范围内的光,该特定波长的光再次被反射后均可以从微结构子层31中射出,提升特定波长范围内的光的透过率。Specifically, in actual use, a single-layer microstructure sublayer 31 can be set as needed. The single-layer microstructure sublayer 31 has a specific reflection band, which can selectively reflect light with a wavelength within its reflection band and transmit light with a wavelength not within its reflection band. Therefore, only one layer of microstructure sublayer 31 is set, which can be specifically used to reflect light within a specific wavelength range. The light of the specific wavelength can be emitted from the microstructure sublayer 31 after being reflected again, thereby improving the transmittance of light within the specific wavelength range.

在一些实施例中,所述微结构子层31的厚度为1~10μm,所述微结构层的厚度为10~60μm。In some embodiments, the thickness of the microstructure sublayer 31 is 1-10 μm, and the thickness of the microstructure layer is 10-60 μm.

具体地,所述微结构子层31的厚度为1~10μm,所述微结构子层31的厚度范围在这个范围内时,微结构子层31的出光效率较好。当厚度太厚或太薄都会影响出光效率。Specifically, the thickness of the microstructure sublayer 31 is 1-10 μm. When the thickness of the microstructure sublayer 31 is within this range, the light extraction efficiency of the microstructure sublayer 31 is better. When the thickness is too thick or too thin, the light extraction efficiency will be affected.

当所述微结构层包括多层叠置的微结构子层31时,各个微结构子层31之间可以使用光学透明胶来连接,所述微结构层的厚度为多个微结构子层31的厚度和多个光学透明胶层的厚度之和。因此,所述微结构层的厚度为10~60μm,所述微结构层的厚度范围在这个范围内时,微结构层的出光效率较好,当厚度太厚或太薄都会影响出光效率,并且不利于微结构层的制作。When the microstructure layer includes multiple stacked microstructure sublayers 31, each microstructure sublayer 31 can be connected by using an optically transparent adhesive, and the thickness of the microstructure layer is the sum of the thickness of the multiple microstructure sublayers 31 and the thickness of the multiple optically transparent adhesive layers. Therefore, the thickness of the microstructure layer is 10 to 60 μm. When the thickness of the microstructure layer is within this range, the light extraction efficiency of the microstructure layer is better. When the thickness is too thick or too thin, the light extraction efficiency will be affected and it is not conducive to the production of the microstructure layer.

在一些实施例中,所述微结构层和所述微结构子层31的雾度均小于或等于3%。In some embodiments, the haze of the microstructure layer and the microstructure sub-layer 31 are both less than or equal to 3%.

具体地,雾度指的是偏离入射光2.5°角以上的透射光强占总透射光强的百分数,雾度越大意味着薄膜光泽以及透明度尤其成像度下降。Specifically, haze refers to the percentage of the transmitted light intensity that deviates from the incident light by more than 2.5° to the total transmitted light intensity. The greater the haze, the lower the gloss and transparency of the film, especially the imaging quality.

本实施例中,所述微结构层和所述微结构子层31的雾度均小于或等于3%,当雾度在这个范围内时,微结构层和微结构子层31引起的色偏较小,正面出光效率较高。当雾度大于3%时,微结构层和微结构子层31导致光发散严重,引起较严重的色偏。In this embodiment, the haze of the microstructure layer and the microstructure sublayer 31 is less than or equal to 3%. When the haze is within this range, the color deviation caused by the microstructure layer and the microstructure sublayer 31 is small, and the front light extraction efficiency is high. When the haze is greater than 3%, the microstructure layer and the microstructure sublayer 31 cause serious light divergence, causing more serious color deviation.

在一些实施例中,所述微结构层的10≤Ra≤30、20≤Rq≤100,所述微结构子层的5≤Ra≤20、10≤Rq≤30。其中,Ra为算数平均粗糙度;Rq为均方根粗糙度。In some embodiments, the microstructure layer has 10≤Ra≤30, 20≤Rq≤100, and the microstructure sublayer has 5≤Ra≤20, 10≤Rq≤30. Ra is the arithmetic mean roughness, and Rq is the root mean square roughness.

具体地,Ra和Rq在这个范围内,既可以保证微结构层和微结构子层31的膜层平整度和光滑度良好,同时避免制作工艺太过复杂。当Ra或Rq太小时,膜层平整度和光滑度良好,但是对制作工艺要求太高,不利于量产;当Ra或Rq太大时,膜层平整度和光滑度不够。Specifically, when Ra and Rq are within this range, the flatness and smoothness of the film layer of the microstructure layer and the microstructure sublayer 31 can be ensured to be good, while avoiding the manufacturing process being too complicated. When Ra or Rq is too small, the flatness and smoothness of the film layer are good, but the manufacturing process requirements are too high, which is not conducive to mass production; when Ra or Rq is too large, the flatness and smoothness of the film layer are not enough.

在一些实施例中,所述微结构层由含有液晶的微结构、聚合物单体和光引发剂的混合物制成。In some embodiments, the microstructure layer is made of a mixture of microstructures containing liquid crystals, polymer monomers, and photoinitiators.

具体地,所述含有液晶的微结构为含有胆甾相液晶的微胶囊,所述胆甾相液晶微胶囊包括芯材料和包裹于所述芯材料外部的壳材料,所述芯材料包含以下重量份数的组分:65%~85%的向列相液晶、10%~30%的左旋或右旋的胆甾相液晶、4%~5%的手性添加剂。Specifically, the liquid crystal-containing microstructure is a microcapsule containing cholesteric liquid crystal, and the cholesteric liquid crystal microcapsule includes a core material and a shell material wrapped around the core material, and the core material contains the following components in weight proportions: 65% to 85% of nematic liquid crystal, 10% to 30% of left-handed or right-handed cholesteric liquid crystal, and 4% to 5% of a chiral additive.

所述手性添加剂可以改变胆甾相液晶的螺距,具体地,所述手性添加剂可以为

Figure BDA0004073209810000091
中的至少一种。通过在芯材料中添加手性添加剂,通过改变手性添加剂的添加量可以改变胆甾相液晶的螺距,进而改变其反射波段,以使得包含有胆甾相液晶的微结构层可以根据需要透过不同波长的光,提升不同颜色光的出光效率。The chiral additive can change the helical pitch of the cholesteric liquid crystal. Specifically, the chiral additive can be
Figure BDA0004073209810000091
By adding a chiral additive to the core material, the pitch of the cholesteric liquid crystal can be changed by changing the amount of the chiral additive added, thereby changing its reflection band, so that the microstructure layer containing the cholesteric liquid crystal can transmit light of different wavelengths as needed, thereby improving the light extraction efficiency of light of different colors.

所述聚合物单体可以为丙烯酸类、甲基丙烯酸类和乙烯基类单体。具体地,所述聚合物单体可以为丙烯酸、丙烯酸甲酯、丙烯酸乙酯、丙烯酸正丁酯、丙烯酸正丁酯、丙烯酸仲丁酯、丙烯酸叔丁酯、丙烯酸正丙脂、丙烯酸环己脂、丙烯酸月桂脂、丙烯酸-2-乙基乙酯、甲基丙烯酸甲酯、甲基丙烯酸乙酯、甲基丙烯酸正丁酯、甲基丙烯酸-2-乙基乙酯、甲基丙烯酸异冰片脂、苯乙烯、丙烯晴、醋酸乙烯脂、丙烯酰胺、丙烯酸-2-羟基乙酯、丙烯酸-2-羟基丙酯、甲基丙烯酸-2-羟基乙酯、甲基丙烯酸-2-羟基丙酯、甲基丙烯酸三氟乙酯、甲基丙烯酸缩水甘油酯、N-羟甲基丙烯酸胺、N-丁氧基甲基丙烯酸胺、二乙烯基苯、乙烯基三甲氧基硅烷等。The polymer monomers may be acrylic acid, methacrylic acid and vinyl monomers. Specifically, the polymer monomers may be acrylic acid, methyl acrylate, ethyl acrylate, n-butyl acrylate, n-butyl acrylate, sec-butyl acrylate, tert-butyl acrylate, n-propyl acrylate, cyclohexyl acrylate, lauryl acrylate, 2-ethylethyl acrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, 2-ethylethyl methacrylate, isobornyl methacrylate, styrene, acrylonitrile, vinyl acetate, acrylamide, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, trifluoroethyl methacrylate, glycidyl methacrylate, N-hydroxymethyl acrylate, N-butoxymethyl acrylate, divinylbenzene, vinyltrimethoxysilane, etc.

在辐照条件下(例如紫外等照射下),聚合物单体之间会发生聚合反应,使得各个颗粒状的胆甾相液晶微胶囊可以更好的连接在一起,进而使得整个微结构层中的胆甾相液晶微胶囊可以均匀分布,增加胆甾相液晶微胶囊层的均匀性和稳定性。Under irradiation conditions (such as ultraviolet irradiation), a polymerization reaction will occur between the polymer monomers, so that the individual granular cholesteric liquid crystal microcapsules can be better connected together, thereby making the cholesteric liquid crystal microcapsules in the entire microstructure layer evenly distributed, thereby increasing the uniformity and stability of the cholesteric liquid crystal microcapsule layer.

所述光引发剂可以为安息香双甲醚、安息香丁醚、安息香乙醚中的一种或多种。光引发剂的不同比例搭配具有强的协同效应,匹配聚合物单体以及辐照条件,提高了光引发的效率,使聚物物单体的自由基聚合,聚合过程充分可控,实现液晶分子的均匀分布。The photoinitiator can be one or more of benzoin dimethyl ether, benzoin butyl ether, and benzoin ethyl ether. The different proportions of the photoinitiators have a strong synergistic effect, match the polymer monomers and irradiation conditions, improve the efficiency of photoinitiation, make the free radical polymerization of the polymer monomers, make the polymerization process fully controllable, and achieve uniform distribution of liquid crystal molecules.

参考图6,本申请第二方面提供了一种显示基板,包括:Referring to FIG6 , the second aspect of the present application provides a display substrate, including:

基底1,包括折叠区和非折叠区;A substrate 1, comprising a folding area and a non-folding area;

发光结构层2,设置于所述基底1上;A light emitting structure layer 2 is disposed on the substrate 1;

上述第一方面任一项所述的增亮膜3,设置于所述发光结构层2远离所述基底1的一侧,所述增亮膜3在所述基底1上的正投影至少覆盖所述折叠区;The brightness enhancement film 3 described in any one of the first aspects above is arranged on a side of the light emitting structure layer 2 away from the substrate 1, and the orthographic projection of the brightness enhancement film 3 on the substrate 1 at least covers the folding area;

防反射层4,设置于所述增亮膜3远离所述基底1的一侧。The anti-reflection layer 4 is disposed on a side of the brightness enhancement film 3 away from the substrate 1 .

具体地,所述基底1为柔性基底1,所述基底1可以由聚酰亚胺(PI)、聚碳酸酯(PC)、聚醚砜(PES)、聚对苯二甲酸乙二醇酯(PET)、聚萘二甲酸乙二醇酯(PEN)、多芳基化合物(PAR)或玻璃纤维增强塑料(FRP)等聚合物材料制成。Specifically, the substrate 1 is a flexible substrate 1, and the substrate 1 can be made of polymer materials such as polyimide (PI), polycarbonate (PC), polyethersulfone (PES), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyarylate (PAR) or fiberglass reinforced plastic (FRP).

所述发光结构层2包括被像素定义层限定的多个像素开口所形成的多个发光区,多个发光区包括发出第一颜色光的第一发光区、发出第二颜色光的第二发光区和发出第三颜色光的第三发光区。所述第一颜色光、所述第二颜色光、所述第三颜色光的波长不同,例如,所述第一颜色光可以为红光,所述第二颜色光可以为绿光,所述第三颜色光可以为蓝光。The light emitting structure layer 2 includes a plurality of light emitting areas formed by a plurality of pixel openings defined by a pixel definition layer, and the plurality of light emitting areas include a first light emitting area emitting a first color light, a second light emitting area emitting a second color light, and a third light emitting area emitting a third color light. The wavelengths of the first color light, the second color light, and the third color light are different. For example, the first color light may be red light, the second color light may be green light, and the third color light may be blue light.

所述增亮膜3设置于所述发光结构层2远离所述基底1的一侧,所述增亮膜3在所述基底1上的正投影至少覆盖所述折叠区。由于增亮膜3中的微结构不易流动,稳定性好,当增亮膜3在所述基底1上的正投影覆盖所述折叠区时,增亮膜3的设置可以避免折叠区内的液晶向周边流动,进而可以避免出现因液晶流动造成的显示基板折叠区和非折叠区的液晶分布不均匀导致的光透过率不同的问题,有效提升显示基板的弯折性能。至于所述基底1的非折叠区是否设置所述增亮膜3,依据实际需求进行设定,在此不做限定。The brightness enhancement film 3 is arranged on the side of the light-emitting structure layer 2 away from the substrate 1, and the orthographic projection of the brightness enhancement film 3 on the substrate 1 at least covers the folding area. Since the microstructure in the brightness enhancement film 3 is not easy to flow and has good stability, when the orthographic projection of the brightness enhancement film 3 on the substrate 1 covers the folding area, the setting of the brightness enhancement film 3 can prevent the liquid crystal in the folding area from flowing to the periphery, thereby avoiding the problem of different light transmittance caused by uneven distribution of liquid crystal in the folding area and non-folding area of the display substrate caused by the flow of liquid crystal, and effectively improves the bending performance of the display substrate. As for whether the brightness enhancement film 3 is set in the non-folding area of the substrate 1, it is set according to actual needs and is not limited here.

所述防反射层4包括线偏振片和1/4λ波片,其中1/4λ波片靠近所述增亮膜3设置,所述线偏振片远离所述增亮膜3设置。通过设置防反射膜层,可以解决环境光经由发光结构层2反射而引起的在明视场下对比度下降的问题,但是会引起显示面板出光强度降低的问题。The anti-reflection layer 4 includes a linear polarizer and a 1/4λ wave plate, wherein the 1/4λ wave plate is arranged close to the brightness enhancement film 3, and the linear polarizer is arranged away from the brightness enhancement film 3. By providing the anti-reflection film layer, the problem of contrast reduction in the bright field caused by the reflection of ambient light through the light-emitting structure layer 2 can be solved, but it will cause the problem of reduced light intensity of the display panel.

本申请中,通过设置增亮膜3,可以改善因设置防反射层4导致的出光效率降低的问题,提升显示面板的出光强度和出光亮度。同时,由于增亮膜3中的微结构不易流动,稳定性好,可以避免出现因液晶流动造成的显示面板折叠区和非折叠区的光透过率不同的问题,改善色偏,且有效提升显示面板的弯折性能。In the present application, by providing the brightness enhancement film 3, the problem of reduced light extraction efficiency caused by providing the anti-reflection layer 4 can be improved, and the light extraction intensity and brightness of the display panel can be improved. At the same time, since the microstructure in the brightness enhancement film 3 is not easy to flow and has good stability, the problem of different light transmittances between the folding area and the non-folding area of the display panel caused by the flow of liquid crystal can be avoided, the color deviation can be improved, and the bending performance of the display panel can be effectively improved.

在一些实施例中,所述微结构层包括依次叠置的三层微结构子层31,所述三层微结构子层31的反射波段与所述第一颜色光的波长、第二颜色光的波长和第三颜色光的波长一一对应。In some embodiments, the microstructure layer includes three microstructure sublayers 31 stacked in sequence, and the reflection bands of the three microstructure sublayers 31 correspond one-to-one to the wavelength of the first color light, the wavelength of the second color light, and the wavelength of the third color light.

具体地,每个所述微结构子层31的反射波段不同,使得每个微结构子层31仅可以反射波长在其反射波段内的光,而透过其他波长不在其反射波段内的光。本实施例中,所述三层微结构子层31的反射波段与所述第一颜色光的波长、第二颜色光的波长和第三颜色光的波长一一对应,例如,第一层微结构子层31的反射波段与所述第一颜色光的波长对应,第一层微结构子层31可以允许一部分第一颜色光透过,其余的第一颜色光被第一层微结构子层31反射,反射后的第一颜色光照射到发光结构层2后,再次被发光结构层2反射,反射后的第一颜色光的旋向相反,此时旋向相反的第一颜色光就可以继续透过第一层微结构子层31,然后从防反射层4中射出,如此就可以提高第一颜色光的透过率,增强第一颜色光的出光效率。Specifically, the reflection band of each microstructure sublayer 31 is different, so that each microstructure sublayer 31 can only reflect light with a wavelength within its reflection band, and transmit light with other wavelengths that are not within its reflection band. In this embodiment, the reflection bands of the three microstructure sublayers 31 correspond to the wavelengths of the first color light, the second color light, and the third color light. For example, the reflection band of the first microstructure sublayer 31 corresponds to the wavelength of the first color light. The first microstructure sublayer 31 allows a portion of the first color light to pass through, and the rest of the first color light is reflected by the first microstructure sublayer 31. After the reflected first color light is irradiated to the light-emitting structure layer 2, it is reflected by the light-emitting structure layer 2 again. The reflected first color light has an opposite rotation direction. At this time, the first color light with an opposite rotation direction can continue to pass through the first microstructure sublayer 31, and then be emitted from the anti-reflection layer 4. In this way, the transmittance of the first color light can be improved and the light extraction efficiency of the first color light can be enhanced.

三层微结构子层31分别用于反射不同波长的颜色光,这些不同波长的颜色光被反射后旋向改变,以致其大部分都可以透过微结构子层31,最终使得具有不同波长的各种颜色的光(例如红光、绿光和蓝光)都可以透过微结构层,进而提升白光的出光效率。The three microstructure sub-layers 31 are respectively used to reflect colored light of different wavelengths. The rotation directions of these colored lights of different wavelengths are changed after reflection, so that most of them can pass through the microstructure sub-layer 31. Ultimately, various colors of light with different wavelengths (such as red light, green light and blue light) can pass through the microstructure layer, thereby improving the light extraction efficiency of white light.

在一些实施例中,所述微结构层为单层微结构子层31,所述微结构子层31的反射波段与所述第一颜色光的波长、第二颜色光的波长或第三颜色光的波长对应。In some embodiments, the microstructure layer is a single-layer microstructure sublayer 31 , and a reflection band of the microstructure sublayer 31 corresponds to the wavelength of the first color light, the wavelength of the second color light, or the wavelength of the third color light.

具体地,实际使用时,可以根据需要设置单层的微结构子层31,该单层的微结构子层31具有特定的反射波段,其可以选择性的反射波长位于其反射波段内的光,而透过波长不在其反射波段的光,因此,仅设置一层微结构子层31,可以专门用于提升特定波长范围内的光的透过率,提升其出光强度。例如,所述微结构层为单层微结构子层31,所述单层的微结构子层31的反射波段与第一颜色光的波长对应,则该单层微结构子层专门用于提升第一颜色光的透过率,提升其出光强度。Specifically, in actual use, a single-layer microstructure sublayer 31 can be provided as needed, and the single-layer microstructure sublayer 31 has a specific reflection band, which can selectively reflect light with a wavelength within its reflection band, and transmit light with a wavelength outside its reflection band. Therefore, only one layer of microstructure sublayer 31 is provided, which can be specifically used to improve the transmittance of light within a specific wavelength range and improve its light output intensity. For example, if the microstructure layer is a single-layer microstructure sublayer 31, and the reflection band of the single-layer microstructure sublayer 31 corresponds to the wavelength of the first color light, then the single-layer microstructure sublayer is specifically used to improve the transmittance of the first color light and improve its light output intensity.

在一些实施例中,参考图7,所述显示基板还包括驱动电路层5,所述驱动电路层5设置于所述发光结构层2靠近所述基底1的一侧。驱动电路层5可以包括构成像素驱动电路的多个晶体管和存储电容。In some embodiments, referring to Fig. 7, the display substrate further includes a driving circuit layer 5, and the driving circuit layer 5 is disposed on a side of the light emitting structure layer 2 close to the substrate 1. The driving circuit layer 5 may include a plurality of transistors and storage capacitors constituting a pixel driving circuit.

在一些实施例中,继续参考图7,所述显示基板还包括封装结构层6,所述封装结构层6设置于所述发光结构层2远离所述基底1的一侧。封装结构层6可以包括叠设的第一子层、第二子层和第三子层,第一子层和第三子层可以采用无机材料,第二子层可以采用有机材料。In some embodiments, referring to FIG7 , the display substrate further includes an encapsulation structure layer 6, which is disposed on a side of the light emitting structure layer 2 away from the substrate 1. The encapsulation structure layer 6 may include a first sublayer, a second sublayer, and a third sublayer stacked together, the first sublayer and the third sublayer may be made of inorganic materials, and the second sublayer may be made of organic materials.

在一些实施例中,继续参考图7,所述显示基板还包括触控层7,所述触控层7设置于所述封装结构层6远离所述基底1的一侧,所述增亮膜3设置在所述触控层7上。触控层7可以是柔性多层覆盖表面式(Flexible Multi Layer On Cell,简称FMLOC)结构,触控层7可以包括第一触控绝缘层、第一金属网格层、第二触控绝缘层、第二金属网格层和第三触控绝缘层,第一触控绝缘层可以位于第一金属网格层靠近基底1的一侧,第二触控绝缘层可以位于第一金属网格层远离基底1的一侧,第二金属网格层可以位于第二触控绝缘层远离基底1的一侧,第三触控绝缘层可以位于第二金属网格层远离基底1的一侧。In some embodiments, with continued reference to FIG. 7 , the display substrate further includes a touch layer 7, the touch layer 7 is disposed on a side of the encapsulation structure layer 6 away from the substrate 1, and the brightness enhancement film 3 is disposed on the touch layer 7. The touch layer 7 may be a flexible multi-layer on-cell (FMLOC) structure, and the touch layer 7 may include a first touch insulating layer, a first metal mesh layer, a second touch insulating layer, a second metal mesh layer, and a third touch insulating layer, the first touch insulating layer may be located on a side of the first metal mesh layer close to the substrate 1, the second touch insulating layer may be located on a side of the first metal mesh layer away from the substrate 1, the second metal mesh layer may be located on a side of the second touch insulating layer away from the substrate 1, and the third touch insulating layer may be located on a side of the second metal mesh layer away from the substrate 1.

参考图8,本申请第三方面提供了一种增亮膜3的制备方法,具体包括如下步骤:Referring to FIG. 8 , the third aspect of the present application provides a method for preparing a brightness enhancement film 3, which specifically comprises the following steps:

步骤S100、将含有液晶的微结构、聚合物单体和光引发剂混合,形成混合体系;Step S100, mixing a microstructure containing liquid crystal, a polymer monomer and a photoinitiator to form a mixed system;

步骤S200、将混合体系铺展,使其形成混合体系预制膜层,通过光照射所述混合体系预制膜层,使混合体系中的光引发剂引发聚合物单体发生聚合反应,得到增亮膜3。Step S200 , spreading the mixed system to form a mixed system prefabricated film layer, irradiating the mixed system prefabricated film layer with light so that the photoinitiator in the mixed system triggers a polymerization reaction of the polymer monomers to obtain a brightness enhancement film 3 .

具体地,步骤S200中将混合体系铺展,使其形成混合体系预制膜层包括:将所述混合体系铺展在基板的表面,所述基板的表面形成所述混合体系预制膜层;或,将所述混合体系装入透明盒状体中,使所述混合体系铺展于透明盒状体中,所述混合体系预制膜层形成在所述透明盒状体中。Specifically, spreading the mixed system in step S200 to form a prefabricated film layer of the mixed system includes: spreading the mixed system on the surface of a substrate, and forming the prefabricated film layer of the mixed system on the surface of the substrate; or loading the mixed system into a transparent box-shaped body, spreading the mixed system in the transparent box-shaped body, and forming the prefabricated film layer of the mixed system in the transparent box-shaped body.

在一些实施例中,所述增亮膜3的制备方法,具体包括如下步骤:In some embodiments, the method for preparing the brightness enhancement film 3 specifically comprises the following steps:

(1)制备透明空盒;(1) preparing a transparent empty box;

(2)在聚合物单体中加入光引发剂,密封避光保存,继续加入包含有液晶的微结构,加热混合得到混合物,待混合物达到清亮点进行搅拌,得到聚合物-液晶微结构混合物;(2) adding a photoinitiator to the polymer monomer, sealing and protecting from light, continuing to add a microstructure containing liquid crystal, heating and mixing to obtain a mixture, and stirring the mixture until it reaches a clearing point to obtain a polymer-liquid crystal microstructure mixture;

(3)将所述聚合物-液晶微结构混合物注入所述空盒中,至空盒被充满,得到填充盒;(3) injecting the polymer-liquid crystal microstructure mixture into the empty box until the empty box is filled to obtain a filled box;

(4)将所述填充盒进行紫外曝光,至所述填充盒内的所述聚合物-液晶结构混合物固化;(4) exposing the filling box to ultraviolet light until the polymer-liquid crystal structure mixture in the filling box is solidified;

(5)去除空盒,得到所述增亮膜3。(5) Remove the empty box to obtain the brightness enhancement film 3.

具体地,所述增亮膜3的制备方法包括如下步骤:Specifically, the method for preparing the brightness enhancement film 3 comprises the following steps:

ITO玻璃清洗:本过程主要运用超声波清洗器,清洗时,首先用洗洁精的水溶液对ITO玻璃超声清洗5分钟,然后将其放入NaOH和酒精的饱和溶液中进行清洗3分钟,最后用去离子水超声清洗3分钟。将洗好的ITO玻璃干燥后,放入无尘箱保存。ITO glass cleaning: This process mainly uses an ultrasonic cleaner. When cleaning, first use a detergent solution to ultrasonically clean the ITO glass for 5 minutes, then put it into a saturated solution of NaOH and alcohol for 3 minutes, and finally use deionized water for ultrasonic cleaning for 3 minutes. After the washed ITO glass is dried, it is stored in a dust-free box.

制备透明空盒:在洗好的玻璃基板ITO面均匀撒上少许间隔子,盖上另一块玻璃基板,压上砝码,用紫外曝光胶对盒子的两边进行密封。制盒工艺的关键在于盒厚均匀,盒厚的差异对膜的光电特性影响很大,在灯光下若盒子干涉条纹很少,则表示盒厚均匀。Prepare a transparent empty box: sprinkle a little spacer evenly on the ITO surface of the washed glass substrate, cover it with another glass substrate, press weights, and seal both sides of the box with UV exposure glue. The key to the box making process is the uniform thickness of the box. The difference in box thickness has a great influence on the photoelectric properties of the film. If the box has few interference fringes under the light, it means that the box thickness is uniform.

混合物配制:在聚合物单体中加入光引发剂,密封避光保存,继续加入包含有液晶的微结构,加热混合得到混合物,待混合物达到清亮点进行搅拌,得到聚合物-液晶微结构混合物;Preparation of the mixture: adding a photoinitiator to the polymer monomer, sealing and protecting from light, adding a microstructure containing liquid crystal, heating and mixing to obtain a mixture, stirring the mixture until it reaches a clearing point, and obtaining a polymer-liquid crystal microstructure mixture;

混合物注入:取出透明空盒,将其一边稍微垫高,用毛细玻璃管将调配好的聚合物-液晶微结构混合物滴在盒内较低的边缘,混合物由低至高浸入透明空盒,有利于聚合物-液晶微结构混合物在盒内均匀分布,待盒内被混合物充满后,将透明空盒移至紫外曝光灯下曝光,通过光照射聚合物-液晶微结构混合物,使混合体系中的光引发剂引发聚合物单体发生聚合反应,最终得到增亮膜3。Injection of mixture: Take out the transparent empty box, slightly raise one side of it, and use a capillary glass tube to drop the prepared polymer-liquid crystal microstructure mixture on the lower edge of the box. The mixture is immersed in the transparent empty box from low to high, which is conducive to the uniform distribution of the polymer-liquid crystal microstructure mixture in the box. After the box is filled with the mixture, move the transparent empty box to an ultraviolet exposure lamp for exposure. By irradiating the polymer-liquid crystal microstructure mixture with light, the photoinitiator in the mixed system triggers the polymer monomer to undergo polymerization reaction, and finally a brightening film 3 is obtained.

本申请第四方面提供了一种显示装置,包括上述第二方面任一项所述的显示基板,所述显示基板为有机发光二极管显示基板。所述显示装置具有上述任一实施例所述的技术效果,在此不做赘述。The fourth aspect of the present application provides a display device, comprising the display substrate described in any one of the second aspects, wherein the display substrate is an organic light emitting diode display substrate. The display device has the technical effects described in any one of the above embodiments, which will not be described in detail here.

所述显示装置可以是具有图像显示功能的产品,例如可以是:显示器、电视、广告牌、数码相框、具有显示功能的激光打印机、电话、手机、个人数字助理(Personal digitalassistant,PDA)、数码相机、便携式摄录机、取景器、导航仪、车辆、大面积墙壁、家电、信息查询设备(如电子政务、银行、医院、电力等部门的业务查询设备、监视器等)。The display device can be a product with an image display function, for example, it can be: a monitor, a television, a billboard, a digital photo frame, a laser printer with a display function, a telephone, a mobile phone, a personal digital assistant (PDA), a digital camera, a portable camcorder, a viewfinder, a navigator, a vehicle, a large-area wall, a home appliance, an information query device (such as business query equipment and monitors of e-government, banks, hospitals, power and other departments).

以下结合具体实施例及对比例来对本申请进行进一步解释说明,并对本申请的实施效果进行测试。The present application is further explained below in conjunction with specific embodiments and comparative examples, and the implementation effect of the present application is tested.

实施例1Example 1

一种增亮膜,包括含有胆甾相液晶的微结构层,所述微结构层中包含多个微胶囊,所述微胶囊中包含所述胆甾相液晶。所述微结构层包括三层叠置的微结构子层,所述三层微结构子层的反射波段与红光的波长、绿光的波长和蓝光的波长一一对应。A brightness enhancement film includes a microstructure layer containing cholesteric liquid crystal, wherein the microstructure layer contains a plurality of microcapsules, and the microcapsules contain the cholesteric liquid crystal. The microstructure layer includes three stacked microstructure sublayers, and the reflection bands of the three microstructure sublayers correspond to the wavelengths of red light, green light, and blue light.

对比例1Comparative Example 1

一种增亮膜,包括胆甾相液晶层,所述胆甾相液晶层包括三层叠置的第一液晶层、第二液晶层和第三液晶层,所述三层液晶层的反射波段与红光的波长、绿光的波长和蓝光的波长一一对应。其中,所述胆甾相液晶层中的液晶为可流动的液晶。A brightness enhancement film includes a cholesteric liquid crystal layer, wherein the cholesteric liquid crystal layer includes a first liquid crystal layer, a second liquid crystal layer, and a third liquid crystal layer stacked in three layers, wherein the reflection bands of the three liquid crystal layers correspond to the wavelengths of red light, green light, and blue light, respectively. The liquid crystal in the cholesteric liquid crystal layer is a flowable liquid crystal.

将实施例1和对比例1的增亮膜用紫外-可见吸收分光光度计在200~900nm范围测试其透射率,用标准雾度计测量其雾度,光学测试结果如下表1所示。The transmittance of the brightness enhancement films of Example 1 and Comparative Example 1 was tested in the range of 200-900 nm using an ultraviolet-visible absorption spectrophotometer, and the haze was measured using a standard haze meter. The optical test results are shown in Table 1 below.

表1实施例1和对比例1的增亮膜弯折前的光学测试数据Table 1 Optical test data of the brightness enhancement films of Example 1 and Comparative Example 1 before bending

Figure BDA0004073209810000141
Figure BDA0004073209810000141

由上表1可知,实施例1和对比例1的增亮膜的反射波段在445~680nm,红光、绿光及蓝光的波长范围都在该反射波段内,因此该增亮膜可以反射红绿蓝三色光,即反射白光。It can be seen from Table 1 above that the reflection band of the brightness enhancement film of Example 1 and Comparative Example 1 is 445-680nm, and the wavelength ranges of red light, green light and blue light are all within this reflection band, so the brightness enhancement film can reflect red, green and blue light, that is, reflect white light.

对比例1中,445~680nm范围的白光透过率为41%(现有行业标准:白光的透过率大于40%),说明对比例1中的增亮膜有较好的光学性质,能较好地透过可见光。In Comparative Example 1, the white light transmittance in the range of 445 to 680 nm is 41% (the current industry standard: the white light transmittance is greater than 40%), which indicates that the brightness enhancement film in Comparative Example 1 has good optical properties and can transmit visible light well.

实施例1中,445~680nm范围的白光透过率高达46%,说明实施例1的增亮膜有优异的光学性质,能高效地透过可见光。In Example 1, the white light transmittance in the range of 445 to 680 nm is as high as 46%, which indicates that the brightness enhancement film of Example 1 has excellent optical properties and can efficiently transmit visible light.

将实施例1和对比例1的增亮膜在3mm弯折半径下弯折20万次,继续对弯折20万次后的增亮膜进行光学性质进行测试,测试结果如下表2所示。实施例1得到的增亮膜3的示意图参考图9,其中中间部分为弯折区32,两边的部分为非弯折区33。The brightness enhancement films of Example 1 and Comparative Example 1 were bent 200,000 times at a bending radius of 3 mm, and the optical properties of the brightness enhancement films after being bent 200,000 times were tested. The test results are shown in Table 2. The schematic diagram of the brightness enhancement film 3 obtained in Example 1 is shown in FIG9 , wherein the middle portion is a bending area 32 and the portions on both sides are non-bending areas 33.

表2实施例1和对比例1的增亮膜弯折后的光学测试数据Table 2 Optical test data of the brightness enhancement films of Example 1 and Comparative Example 1 after bending

Figure BDA0004073209810000142
Figure BDA0004073209810000142

由表2可知,相较于对比例1,实施例1中弯折区32与非弯折区33之间的光学参数变化更小,说明实施例1的增亮膜3的稳定性更强,弯折性能更好。这是由于,实施例1中将胆甾相液晶用微胶囊化的方法做成了胆甾相液晶微胶囊结构,微胶囊结构实现了液晶的分散、致稳和保护,提升膜层的弯折性能,避免在弯折时造成液晶的流动,进而造成弯折区和非弯折区液晶分布不均匀,以致两个区域的光透过率不同的问题。As can be seen from Table 2, compared with Comparative Example 1, the optical parameter variation between the bending area 32 and the non-bending area 33 in Example 1 is smaller, indicating that the brightness enhancement film 3 of Example 1 is more stable and has better bending performance. This is because in Example 1, the cholesteric liquid crystal is made into a cholesteric liquid crystal microcapsule structure by a microencapsulation method, and the microcapsule structure achieves the dispersion, stabilization and protection of the liquid crystal, improves the bending performance of the film layer, and avoids the flow of the liquid crystal during bending, thereby causing the uneven distribution of the liquid crystal in the bending area and the non-bending area, resulting in different light transmittances in the two areas.

实施例2Example 2

一种增亮膜,包括含有胆甾相液晶的微结构层,所述微结构层中包含多个微胶囊,所述微胶囊中包含所述胆甾相液晶液晶。所述微结构层为单层微结构子层,所述单层微结构子层的反射波段与蓝光的波长对应,所述增亮膜用于反射蓝光。A brightness enhancement film comprises a microstructure layer containing cholesteric liquid crystal, wherein the microstructure layer comprises a plurality of microcapsules, wherein the microcapsules comprise the cholesteric liquid crystal. The microstructure layer is a single-layer microstructure sublayer, the reflection band of the single-layer microstructure sublayer corresponds to the wavelength of blue light, and the brightness enhancement film is used to reflect blue light.

对比例2Comparative Example 2

一种增亮膜,包括胆甾相液晶层,所述胆甾相液晶层为单层液晶层,所述单层液晶层的反射波段与蓝光的波长对应,所述增亮膜用于反射蓝光。其中,所述胆甾相液晶层中的液晶为可流动的液晶。A brightness enhancement film comprises a cholesteric liquid crystal layer, wherein the cholesteric liquid crystal layer is a single-layer liquid crystal layer, the reflection band of the single-layer liquid crystal layer corresponds to the wavelength of blue light, and the brightness enhancement film is used to reflect blue light. The liquid crystal in the cholesteric liquid crystal layer is a flowable liquid crystal.

将实施例2和对比例2的增亮膜用紫外-可见吸收分光光度计在200~900nm范围测试其透射率,用标准雾度计测量其雾度,光学测试结果如下表3所示。The transmittance of the brightness enhancement films of Example 2 and Comparative Example 2 was tested in the range of 200-900 nm using an ultraviolet-visible absorption spectrophotometer, and the haze was measured using a standard haze meter. The optical test results are shown in Table 3 below.

表3实施例2和对比例2的增亮膜弯折前的光学测试数据Table 3 Optical test data of the brightness enhancement films of Example 2 and Comparative Example 2 before bending

Figure BDA0004073209810000151
Figure BDA0004073209810000151

由上表3可知,实施例2和对比例2的增亮膜的反射波段在445~480nm,蓝光的波长范围在该反射波段内,因此该增亮膜可以专门用于反射蓝光,而其他的红光及绿光绝大部分都可以透过。It can be seen from Table 3 above that the reflection band of the brightness enhancement film of Example 2 and Comparative Example 2 is 445-480 nm, and the wavelength range of blue light is within this reflection band. Therefore, the brightness enhancement film can be used specifically to reflect blue light, while most of the other red light and green light can be transmitted.

对比例2中,445~680nm范围的蓝光透过率为43%,505~680nm范围的红光及绿光的透过率为88%,而实施例2中蓝光透过率为49%,红光及绿光的透过率为93%,由此可见,实施例2中,使用液晶微胶囊层,对蓝光、绿光及红光的透过率均有改善。同时,其可以选择性地仅反射蓝光,将该增亮膜用于显示面板时,其反射蓝光后,蓝光照射到发光结构层上再被反射,其旋向发生改变,最终几乎所有的蓝光均可以从增亮膜及防反射层中射出,提高了蓝光的正面出光效率。In comparative example 2, the transmittance of blue light in the range of 445-680nm is 43%, and the transmittance of red light and green light in the range of 505-680nm is 88%, while the transmittance of blue light in example 2 is 49%, and the transmittance of red light and green light is 93%. It can be seen that in example 2, the use of the liquid crystal microcapsule layer improves the transmittance of blue light, green light and red light. At the same time, it can selectively reflect only blue light. When the brightness enhancement film is used in a display panel, after it reflects blue light, the blue light is irradiated on the light-emitting structure layer and then reflected, and its rotation direction changes. In the end, almost all blue light can be emitted from the brightness enhancement film and the anti-reflection layer, which improves the front light output efficiency of blue light.

将实施例2和对比例2的增亮膜在3mm弯折半径下弯折20万次,继续对增亮膜光学性质进行测试,测试结果如下表4所示。The brightness enhancement films of Example 2 and Comparative Example 2 were bent 200,000 times at a bending radius of 3 mm, and the optical properties of the brightness enhancement films were further tested. The test results are shown in Table 4 below.

表4实施例2和对比例2的增亮膜弯折后的光学测试数据Table 4 Optical test data of the brightness enhancement films of Example 2 and Comparative Example 2 after bending

Figure BDA0004073209810000161
Figure BDA0004073209810000161

由表3可知,相较于对比例2,实施例2中弯折区与非弯折区之间的光学参数变化更小,说明实施例2的增亮膜的稳定性更强,弯折性能更好。这是由于,实施例2中将胆甾相液晶用微胶囊化的方法做成了胆甾相液晶微胶囊结构,微胶囊结构实现了液晶的分散、致稳和保护,提升膜层的弯折性能,避免在弯折时造成液晶的流动,进而造成弯折区和非弯折区液晶分布不均匀,以致两个区域的光透过率不同。As can be seen from Table 3, compared with Comparative Example 2, the optical parameter variation between the bending area and the non-bending area in Example 2 is smaller, indicating that the brightness enhancement film of Example 2 is more stable and has better bending performance. This is because in Example 2, the cholesteric liquid crystal is made into a cholesteric liquid crystal microcapsule structure by a microencapsulation method, and the microcapsule structure achieves the dispersion, stabilization and protection of the liquid crystal, improves the bending performance of the film layer, and avoids the flow of the liquid crystal during bending, thereby causing the liquid crystal to be unevenly distributed in the bending area and the non-bending area, resulting in different light transmittances in the two areas.

实施例3Example 3

一种增亮膜,包括含有胆甾相液晶的微结构层,所述微结构层中包含多个微胶囊,所述微胶囊中包含所述胆甾相液晶。所述微结构层为单层微结构子层,所述单层微结构子层的反射波段与绿光的波长对应,所述增亮膜用于反射绿光。A brightness enhancement film comprises a microstructure layer containing cholesteric liquid crystal, wherein the microstructure layer comprises a plurality of microcapsules, and the microcapsules comprise the cholesteric liquid crystal. The microstructure layer is a single-layer microstructure sublayer, and the reflection band of the single-layer microstructure sublayer corresponds to the wavelength of green light. The brightness enhancement film is used to reflect green light.

对比例3Comparative Example 3

一种增亮膜,包括含有胆甾相液晶层,所述胆甾相液晶层为单层液晶层,所述单层液晶层的反射波段与绿光的波长对应,所述增亮膜用于反射绿光。其中,所述胆甾相液晶层中的液晶为可流动的液晶。A brightness enhancement film includes a cholesteric liquid crystal layer, wherein the cholesteric liquid crystal layer is a single-layer liquid crystal layer, the reflection band of the single-layer liquid crystal layer corresponds to the wavelength of green light, and the brightness enhancement film is used to reflect green light. The liquid crystal in the cholesteric liquid crystal layer is a flowable liquid crystal.

将实施例3和对比例3的增亮膜用紫外-可见吸收分光光度计在200~900nm范围测试其透射率,用标准雾度计测量其雾度,光学测试结果如下表5所示。The transmittance of the brightness enhancement films of Example 3 and Comparative Example 3 was tested in the range of 200-900 nm using an ultraviolet-visible absorption spectrophotometer, and the haze was measured using a standard haze meter. The optical test results are shown in Table 5 below.

表5实施例3和对比例3的增亮膜弯折前的光学测试数据Table 5 Optical test data of the brightness enhancement films of Example 3 and Comparative Example 3 before bending

Figure BDA0004073209810000162
Figure BDA0004073209810000162

由上表5可知,实施例3和对比例3的增亮膜的反射波段在505~575nm,绿光的波长范围在该反射波段内,因此该增亮膜可以专门用于反射绿光,而其他的红光及蓝光绝大部分都可以透过。It can be seen from Table 5 above that the reflection band of the brightness enhancement film of Example 3 and Comparative Example 3 is 505-575 nm, and the wavelength range of green light is within this reflection band. Therefore, the brightness enhancement film can be used specifically to reflect green light, while most of the other red light and blue light can be transmitted.

对比例3中,445~680nm范围的蓝光透过率为83%,505~575nm范围的绿光透过率为48%,595~680nm范围的红光的透过率为83%,而实施例3中蓝光透过率为89%,绿光透过率为54%,红光透过率为92%,由此可见,实施例3中,使用液晶微胶囊层,对蓝光、绿光及红光的透过率均有改善。同时,其可以选择性地仅反射绿光,将该增亮膜用于显示面板时,其反射绿光后,绿光照射到发光结构层上再被反射,其旋向发生改变,最终几乎所有的绿光均可以从增亮膜及防反射层中射出,提高了绿光的正面出光效率。In comparative example 3, the transmittance of blue light in the range of 445-680nm is 83%, the transmittance of green light in the range of 505-575nm is 48%, and the transmittance of red light in the range of 595-680nm is 83%, while in Example 3, the transmittance of blue light is 89%, the transmittance of green light is 54%, and the transmittance of red light is 92%. It can be seen that in Example 3, the use of the liquid crystal microcapsule layer improves the transmittance of blue light, green light and red light. At the same time, it can selectively reflect only green light. When the brightness enhancement film is used in a display panel, after it reflects green light, the green light is irradiated on the light-emitting structure layer and then reflected, and its rotation direction changes. In the end, almost all green light can be emitted from the brightness enhancement film and the anti-reflection layer, which improves the front light output efficiency of green light.

将实施例3和对比例3的增亮膜在3mm弯折半径下弯折20万次,继续增亮膜进行光学性质进行测试,测试结果如下表6所示。The brightness enhancement films of Example 3 and Comparative Example 3 were bent 200,000 times at a bending radius of 3 mm, and the optical properties of the brightness enhancement films were tested. The test results are shown in Table 6 below.

表6实施例3和对比例3的增亮膜弯折后的光学测试数据Table 6 Optical test data of the brightness enhancement films of Example 3 and Comparative Example 3 after bending

Figure BDA0004073209810000171
Figure BDA0004073209810000171

由表6可知,相较于对比例3,实施例3中弯折区与非弯折区之间的光学参数变化更小,说明实施例3的增亮膜的稳定性更强,弯折性能更好。这是由于,实施例3中将胆甾相液晶用微胶囊化的方法做成了胆甾相液晶微胶囊结构,微胶囊结构实现了液晶的分散、致稳和保护,提升膜层的弯折性能,避免在弯折时造成液晶的流动,进而造成弯折区和非弯折区液晶分布不均匀,以致两个区域的光透过率不同。It can be seen from Table 6 that, compared with Comparative Example 3, the optical parameter variation between the bending area and the non-bending area in Example 3 is smaller, indicating that the brightness enhancement film of Example 3 is more stable and has better bending performance. This is because, in Example 3, the cholesteric liquid crystal is made into a cholesteric liquid crystal microcapsule structure by a microencapsulation method, and the microcapsule structure achieves the dispersion, stabilization and protection of the liquid crystal, improves the bending performance of the film layer, and avoids the flow of the liquid crystal during bending, thereby causing the liquid crystal to be unevenly distributed in the bending area and the non-bending area, resulting in different light transmittances in the two areas.

实施例4Example 4

一种增亮膜,包括含有胆甾相液晶的微结构层,所述微结构层中包含多个微胶囊,所述微胶囊中包含所述胆甾相液晶。所述微结构层为单层微结构子层,所述单层微结构子层的反射波段与红光的波长对应,所述增亮膜用于反射红光。A brightness enhancement film comprises a microstructure layer containing cholesteric liquid crystal, wherein the microstructure layer comprises a plurality of microcapsules, and the microcapsules comprise the cholesteric liquid crystal. The microstructure layer is a single-layer microstructure sublayer, and the reflection band of the single-layer microstructure sublayer corresponds to the wavelength of red light. The brightness enhancement film is used to reflect red light.

对比例4Comparative Example 4

一种增亮膜,包括含有胆甾相液晶层,所述胆甾相液晶层为单层液晶层,所述单层液晶层的反射波段与红光的波长对应,所述增亮膜用于反射红光。其中,所述胆甾相液晶层中的液晶为可流动的液晶。A brightness enhancement film includes a cholesteric liquid crystal layer, wherein the cholesteric liquid crystal layer is a single-layer liquid crystal layer, the reflection band of the single-layer liquid crystal layer corresponds to the wavelength of red light, and the brightness enhancement film is used to reflect red light. The liquid crystal in the cholesteric liquid crystal layer is a flowable liquid crystal.

将实施例4和对比例4的增亮膜用紫外-可见吸收分光光度计在200~900nm范围测试其透射率,用标准雾度计测量其雾度,光学测试结果如下表7所示。The transmittance of the brightness enhancement films of Example 4 and Comparative Example 4 was tested in the range of 200-900 nm using an ultraviolet-visible absorption spectrophotometer, and the haze was measured using a standard haze meter. The optical test results are shown in Table 7 below.

表7实施例4和对比例4的增亮膜弯折前的光学测试数据Table 7 Optical test data of the brightness enhancement films of Example 4 and Comparative Example 4 before bending

Figure BDA0004073209810000181
Figure BDA0004073209810000181

由上表7可知,实施例4和对比例4的增亮膜的反射波段在595~680nm,红光的波长范围在该反射波段内,因此该增亮膜可以专门用于反射红光,而其他的绿光及蓝光绝大部分都可以透过。It can be seen from Table 7 above that the reflection band of the brightness enhancement film of Example 4 and Comparative Example 4 is 595-680nm, and the wavelength range of red light is within this reflection band. Therefore, the brightness enhancement film can be used specifically to reflect red light, while most of the other green light and blue light can be transmitted.

对比例4中,445~575范围的蓝光及绿光的透过率为87%,595~680nm范围的红光的透过率为47%,而实施例4中蓝光级绿光透过率为91%,红光透过率为52%,由此可见,实施例4中,使用液晶微胶囊层,对蓝光、绿光及红光的透过率均有改善。同时,其可以选择性地仅反射红光,将该增亮膜用于显示面板时,其反射红光后,绿光照射到发光结构层上再被反射,其旋向发生改变,最终几乎所有的红光均可以从增亮膜及防反射层中射出,提高了红光的正面出光效率。In comparative example 4, the transmittance of blue light and green light in the range of 445-575nm is 87%, and the transmittance of red light in the range of 595-680nm is 47%, while in example 4, the transmittance of blue light-level green light is 91%, and the transmittance of red light is 52%. It can be seen that in example 4, the use of the liquid crystal microcapsule layer improves the transmittance of blue light, green light and red light. At the same time, it can selectively reflect only red light. When the brightness enhancement film is used in a display panel, after it reflects red light, the green light is irradiated on the light-emitting structure layer and then reflected, and its rotation direction changes. In the end, almost all red light can be emitted from the brightness enhancement film and the anti-reflection layer, which improves the front light output efficiency of red light.

将实施例4和对比例4的增亮膜在3mm弯折半径下弯折20万次,继续对增亮膜光学性质进行测试,测试结果如下表8所示。The brightness enhancement films of Example 4 and Comparative Example 4 were bent 200,000 times at a bending radius of 3 mm, and the optical properties of the brightness enhancement films were further tested. The test results are shown in Table 8 below.

表8实施例4和对比例4的增亮膜弯折后的光学测试数据Table 8 Optical test data of the brightness enhancement films of Example 4 and Comparative Example 4 after bending

Figure BDA0004073209810000182
Figure BDA0004073209810000182

由表8可知,相较于对比例4,实施例4中弯折区与非弯折区之间的光学参数变化更小,说明实施例4的增亮膜的稳定性更强,弯折性能更好。这是由于,实施例4中将胆甾相液晶用微胶囊化的方法做成了胆甾相液晶微胶囊结构,微胶囊结构实现了液晶的分散、致稳和保护,提升膜层的弯折性能,避免在弯折时造成液晶的流动,进而造成弯折区和非弯折区液晶分布不均匀,以致两个区域的光透过率不同。It can be seen from Table 8 that, compared with Comparative Example 4, the optical parameter variation between the bending area and the non-bending area in Example 4 is smaller, indicating that the brightness enhancement film of Example 4 is more stable and has better bending performance. This is because, in Example 4, the cholesteric liquid crystal is made into a cholesteric liquid crystal microcapsule structure by a microencapsulation method, and the microcapsule structure achieves the dispersion, stabilization and protection of the liquid crystal, improves the bending performance of the film layer, and avoids the flow of the liquid crystal during bending, thereby causing the liquid crystal to be unevenly distributed in the bending area and the non-bending area, resulting in different light transmittances in the two areas.

实施例5Example 5

一种显示基板,包括:基底,包括折叠区和非折叠区;发光结构层,设置于所述基底上;实施例1所述的增亮膜,设置于所述发光结构层远离所述基底的一侧,所述增亮膜在所述基底上的正投影至少覆盖所述折叠区;防反射层,设置于所述增亮膜远离所述基底的一侧。其中,所述增亮膜可以用光学透明胶贴附在发光结构层远离所述基底的一侧。A display substrate comprises: a substrate, comprising a folding area and a non-folding area; a light-emitting structure layer, disposed on the substrate; a brightness enhancement film as described in Example 1, disposed on a side of the light-emitting structure layer away from the substrate, wherein the orthographic projection of the brightness enhancement film on the substrate at least covers the folding area; and an anti-reflection layer, disposed on a side of the brightness enhancement film away from the substrate. The brightness enhancement film can be attached to the side of the light-emitting structure layer away from the substrate using an optically transparent adhesive.

对比例5Comparative Example 5

一种显示基板,与实施例5的区别在于:使用对比例1所述的增亮膜。A display substrate, which is different from Example 5 in that the brightness enhancement film described in Comparative Example 1 is used.

基准对比例Benchmark comparison

一种显示基板,与实施例5的区别在于:不设置增亮膜。A display substrate, which is different from the fifth embodiment in that no brightness enhancement film is provided.

将实施例5、对比例5及基准对比例的显示基板采用同样的方式组装为显示面板,分别点亮红、绿、蓝三种像素,测试显示面板的电压、电流、各个像素的亮度变化及色偏等,测试结果如下表9所示。The display substrates of Example 5, Comparative Example 5 and the reference comparative example are assembled into a display panel in the same manner, and the red, green and blue pixels are lighted respectively. The voltage, current, brightness change and color deviation of each pixel of the display panel are tested. The test results are shown in Table 9 below.

测试方式:将显示面板的最终亮度设定为800cdm-2,防反射层和外层保护层的透过率为0.43,也即显示面板未经过防反射层和外层保护层的亮度为1860cdm-2(800/0.43=1860.47≈1860)。Test method: The final brightness of the display panel is set to 800 cdm -2 , and the transmittance of the anti-reflection layer and the outer protective layer is 0.43, that is, the brightness of the display panel without the anti-reflection layer and the outer protective layer is 1860 cdm -2 (800/0.43=1860.47≈1860).

基准对比例中显示面板的基准的色坐标设定如下:红色(0.683,0.317),绿色(0.241,0.722),蓝色(0.138,0.054),白色(0.310,0.320)。The reference color coordinates of the display panel in the reference comparative example are set as follows: red (0.683, 0.317), green (0.241, 0.722), blue (0.138, 0.054), and white (0.310, 0.320).

对比例5和实施例5的色坐标设定如下:红色(0.681,0.319),绿色(0.237,0.724),蓝色(0.138,0.053),白色(0.310,0.320)。显示面板的亚像素个数:红色为1370250个,绿色2740500个,蓝色为1370250个。色偏为测试得到的色坐标与理论设定的色坐标的差值。The color coordinates of Comparative Example 5 and Example 5 are set as follows: red (0.681, 0.319), green (0.237, 0.724), blue (0.138, 0.053), white (0.310, 0.320). The number of sub-pixels of the display panel: 1370250 for red, 2740500 for green, and 1370250 for blue. The color deviation is the difference between the color coordinates obtained by the test and the color coordinates set theoretically.

由表9可知,在显示面板最终亮度相同的测试条件下,相比基准对比例,对比例5和实施例5中的红绿蓝三种像素的像素亮度变化较小,而像素电流都显著减小,显示面板的电流和功耗都显著降低。由此可知,在显示基板中设置胆甾相液晶层和胆甾相液晶微胶囊层都能提升显示面板的出光效率,并降低显示面板功耗,并且色偏较小。It can be seen from Table 9 that under the test conditions of the same final brightness of the display panel, compared with the reference comparative example, the pixel brightness of the red, green and blue pixels in comparative example 5 and embodiment 5 changes less, while the pixel current is significantly reduced, and the current and power consumption of the display panel are significantly reduced. It can be seen that the provision of a cholesteric liquid crystal layer and a cholesteric liquid crystal microcapsule layer in the display substrate can improve the light extraction efficiency of the display panel, reduce the power consumption of the display panel, and have a smaller color deviation.

表9实施例5、对比例5、基准对比例的显示基板未弯折的测试数据Table 9 Test data of the display substrate of Example 5, Comparative Example 5 and Benchmark Comparative Example without bending

Figure BDA0004073209810000201
Figure BDA0004073209810000201

将实施例5、对比例5及基准对比例的显示面板在3mm弯折半径下弯折20万次,继续测试显示面板的电压、电流、各个像素的亮度变化及色偏等,测试结果如下表10所示。The display panels of Example 5, Comparative Example 5 and the reference comparative example were bent 200,000 times at a bending radius of 3 mm, and the voltage, current, brightness change and color deviation of each pixel of the display panels were further tested. The test results are shown in Table 10 below.

表10实施例5、对比例5、基准对比例的显示基板弯折后的测试数据Table 10 Test data of display substrates after bending of Example 5, Comparative Example 5 and Benchmark Comparative Example

Figure BDA0004073209810000202
Figure BDA0004073209810000202

由表10可知,与对比例5和基准对比例相比,实施例5的显示基板在弯折前后其各项性能尤其是色偏变化程度很小,说明实施例5的显示基板的抗弯折性能更好,更稳定。这是由于实施例5中使用了增亮膜,其具有良好的抗弯折性能,将其设置在显示基板上,由于增亮膜中的微结构不易流动,稳定性好,可以避免出现因液晶流动造成的显示基板折叠区和非折叠区的液晶分布不均匀导致的光透过率不同的问题,有效提升显示基板的弯折性能。It can be seen from Table 10 that, compared with Comparative Example 5 and the reference comparative example, the display substrate of Example 5 has a small change in various properties, especially color shift, before and after bending, indicating that the display substrate of Example 5 has better and more stable anti-bending performance. This is because a brightness enhancement film is used in Example 5, which has good anti-bending performance. It is set on the display substrate. Since the microstructure in the brightness enhancement film is not easy to flow and has good stability, the problem of different light transmittance caused by uneven distribution of liquid crystal in the folding area and non-folding area of the display substrate caused by liquid crystal flow can be avoided, and the bending performance of the display substrate is effectively improved.

实施例6Example 6

一种显示基板,包括:基底,包括折叠区和非折叠区;发光结构层,设置于所述基底上;实施例2所述的增亮膜,设置于所述发光结构层远离所述基底的一侧,所述增亮膜在所述基底上的正投影至少覆盖所述折叠区;防反射层,设置于所述增亮膜远离所述基底的一侧。其中,所述增亮膜可以用光学透明胶贴附在发光结构层远离所述基底的一侧。A display substrate comprises: a substrate, comprising a folding area and a non-folding area; a light-emitting structure layer, disposed on the substrate; a brightness enhancement film as described in Example 2, disposed on a side of the light-emitting structure layer away from the substrate, wherein the orthographic projection of the brightness enhancement film on the substrate at least covers the folding area; and an anti-reflection layer, disposed on a side of the brightness enhancement film away from the substrate. The brightness enhancement film can be attached to the side of the light-emitting structure layer away from the substrate using an optically transparent adhesive.

对比例6Comparative Example 6

一种显示基板,与实施例6的区别在于:使用对比例2所述的增亮膜。A display substrate, which is different from Example 6 in that the brightness enhancement film described in Comparative Example 2 is used.

将实施例6、对比例6及基准对比例的显示基板采用同样的方式组装为显示面板,仅点亮蓝光像素,采用与实施例5相同的测试方式,测试显示面板的电压、电流、各个像素的亮度变化及色偏等,测试结果如下表11所示。The display substrates of Example 6, Comparative Example 6 and the benchmark comparative example are assembled into a display panel in the same manner, and only the blue light pixels are lit. The voltage, current, brightness change and color deviation of each pixel of the display panel are tested in the same test method as Example 5. The test results are shown in Table 11 below.

表11实施例6、对比例6、基准对比例的显示基板弯折前的测试数据Table 11 Test data of display substrates before bending of Example 6, Comparative Example 6 and Benchmark Comparative Example

Figure BDA0004073209810000211
Figure BDA0004073209810000211

由表11可知,在显示面板最终亮度相同的测试条件下,相比基准对比例,对比例6和实施例6中的蓝色像素的像素亮度变化较小,而像素电流都显著减小,显示面板的电流和功耗都显著降低。由此可知,在显示基板中设置胆甾相液晶层和胆甾相液晶微胶囊层都能提升显示面板的出光效率,并降低显示面板功耗,并且色偏较小。It can be seen from Table 11 that under the test conditions of the same final brightness of the display panel, compared with the reference comparative example, the pixel brightness of the blue pixel in comparative example 6 and embodiment 6 changes less, while the pixel current is significantly reduced, and the current and power consumption of the display panel are significantly reduced. It can be seen that the provision of a cholesteric liquid crystal layer and a cholesteric liquid crystal microcapsule layer in the display substrate can improve the light extraction efficiency of the display panel, reduce the power consumption of the display panel, and have a smaller color deviation.

将实施例6、对比例6及基准对比例的显示面板在3mm弯折半径下弯折20万次,继续测试显示面板的电压、电流、各个像素的亮度变化及色偏等,测试结果如下表12所示。The display panels of Example 6, Comparative Example 6 and the reference comparative example were bent 200,000 times at a bending radius of 3 mm, and the voltage, current, brightness change and color deviation of each pixel of the display panels were further tested. The test results are shown in Table 12 below.

由表12可知,与对比例6和基准对比例相比,实施例6的显示基板在弯折前后其各项性能尤其是色偏变化程度很小,说明实施例6的显示基板的抗弯折性能更好,更稳定。这是由于实施例6中使用了增亮膜,其具有良好的抗弯折性能,将其设置在显示基板上,由于增亮膜中的微结构不易流动,稳定性好,可以避免出现因液晶流动造成的显示基板折叠区和非折叠区的液晶分布不均匀导致的光透过率不同的问题,有效提升显示基板的弯折性能。It can be seen from Table 12 that, compared with Comparative Example 6 and the reference comparative example, the display substrate of Example 6 has a small change in various properties, especially color shift, before and after bending, indicating that the display substrate of Example 6 has better and more stable anti-bending performance. This is because a brightness enhancement film is used in Example 6, which has good anti-bending performance. It is set on the display substrate. Since the microstructure in the brightness enhancement film is not easy to flow and has good stability, the problem of different light transmittance caused by uneven distribution of liquid crystal in the folding area and non-folding area of the display substrate caused by liquid crystal flow can be avoided, and the bending performance of the display substrate is effectively improved.

表12实施例6、对比例6、基准对比例的显示基板弯折后的测试数据Table 12 Test data of display substrates after bending of Example 6, Comparative Example 6 and Benchmark Comparative Example

Figure BDA0004073209810000221
Figure BDA0004073209810000221

实施例7Example 7

一种显示基板,包括:基底,包括折叠区和非折叠区;发光结构层,设置于所述基底上;实施例3所述的增亮膜,设置于所述发光结构层远离所述基底的一侧,所述增亮膜在所述基底上的正投影至少覆盖所述折叠区;防反射层,设置于所述增亮膜远离所述基底的一侧。其中,所述增亮膜可以用光学透明胶贴附在发光结构层远离所述基底的一侧。A display substrate comprises: a substrate, comprising a folding area and a non-folding area; a light-emitting structure layer, disposed on the substrate; a brightness enhancement film as described in Example 3, disposed on a side of the light-emitting structure layer away from the substrate, wherein the orthographic projection of the brightness enhancement film on the substrate at least covers the folding area; and an anti-reflection layer, disposed on a side of the brightness enhancement film away from the substrate. The brightness enhancement film can be attached to the side of the light-emitting structure layer away from the substrate using an optically transparent adhesive.

对比例7Comparative Example 7

一种显示基板,与实施例7的区别在于:使用对比例3所述的增亮膜。A display substrate, which is different from Example 7 in that the brightness enhancement film described in Comparative Example 3 is used.

将实施例7、对比例7及基准对比例的显示基板采用同样的方式组装为显示面板,仅点亮绿光像素,采用与实施例5相同的测试方式,测试显示面板的电压、电流、各个像素的亮度变化及色偏等,测试结果如下表13所示。The display substrates of Example 7, Comparative Example 7 and the benchmark comparative example are assembled into a display panel in the same manner, and only the green light pixels are lit. The voltage, current, brightness change and color deviation of each pixel of the display panel are tested in the same test method as Example 5. The test results are shown in Table 13 below.

表13实施例7、对比例7、基准对比例的显示基板弯折前的测试数据Table 13 Test data of display substrates before bending of Example 7, Comparative Example 7 and Benchmark Comparative Example

Figure BDA0004073209810000222
Figure BDA0004073209810000222

由表13可知,在显示面板最终亮度相同的测试条件下,相比基准对比例,对比例7和实施例7中的绿色像素的像素亮度变化较小,而像素电流都显著减小,显示面板的电流和功耗都显著降低。由此可知,在显示基板中设置胆甾相液晶层和胆甾相液晶微胶囊层都能提升显示面板的出光效率,并降低显示面板功耗,并且色偏较小。It can be seen from Table 13 that under the test conditions of the same final brightness of the display panel, compared with the reference comparative example, the pixel brightness of the green pixel in comparative example 7 and embodiment 7 changes less, while the pixel current is significantly reduced, and the current and power consumption of the display panel are significantly reduced. It can be seen that the provision of a cholesteric liquid crystal layer and a cholesteric liquid crystal microcapsule layer in the display substrate can improve the light extraction efficiency of the display panel, reduce the power consumption of the display panel, and have a smaller color deviation.

将实施例7、对比例7及基准对比例的显示面板在3mm弯折半径下弯折20万次,继续测试显示面板的电压、电流、各个像素的亮度变化及色偏等,测试结果如下表14所示。The display panels of Example 7, Comparative Example 7 and the benchmark comparative example were bent 200,000 times at a bending radius of 3 mm, and the voltage, current, brightness change and color deviation of each pixel of the display panels were further tested. The test results are shown in Table 14 below.

表14实施例7、对比例7、基准对比例的显示基板弯折后的测试数据Table 14 Test data of display substrates after bending of Example 7, Comparative Example 7 and Benchmark Comparative Example

Figure BDA0004073209810000231
Figure BDA0004073209810000231

由表14可知,与对比例7和基准对比例相比,实施例7的显示基板在弯折前后其各项性能尤其是色偏变化程度很小,说明实施例7的显示基板的抗弯折性能更好,更稳定。这是由于实施例7中使用了增亮膜,其具有良好的抗弯折性能,将其设置在显示基板上,由于增亮膜中的微结构不易流动,稳定性好,可以避免出现因液晶流动造成的显示基板折叠区和非折叠区的液晶分布不均匀导致的光透过率不同的问题,有效提升显示基板的弯折性能。It can be seen from Table 14 that, compared with Comparative Example 7 and the reference comparative example, the display substrate of Example 7 has a small change in various properties, especially color shift, before and after bending, indicating that the display substrate of Example 7 has better and more stable anti-bending performance. This is because a brightness enhancement film is used in Example 7, which has good anti-bending performance. It is set on the display substrate. Since the microstructure in the brightness enhancement film is not easy to flow and has good stability, the problem of different light transmittance caused by uneven distribution of liquid crystal in the folding area and non-folding area of the display substrate caused by liquid crystal flow can be avoided, and the bending performance of the display substrate is effectively improved.

实施例8Example 8

一种显示基板,包括:基底,包括折叠区和非折叠区;发光结构层,设置于所述基底上;实施例4所述的增亮膜,设置于所述发光结构层远离所述基底的一侧,所述增亮膜在所述基底上的正投影至少覆盖所述折叠区;防反射层,设置于所述增亮膜远离所述基底的一侧。其中,所述增亮膜可以用光学透明胶贴附在发光结构层远离所述基底的一侧。A display substrate comprises: a substrate, comprising a folding area and a non-folding area; a light-emitting structure layer, disposed on the substrate; a brightness enhancement film as described in Example 4, disposed on a side of the light-emitting structure layer away from the substrate, wherein the orthographic projection of the brightness enhancement film on the substrate at least covers the folding area; and an anti-reflection layer, disposed on a side of the brightness enhancement film away from the substrate. The brightness enhancement film can be attached to the side of the light-emitting structure layer away from the substrate using an optically transparent adhesive.

对比例8Comparative Example 8

一种显示基板,与实施例8的区别在于:使用对比例4所述的增亮膜。A display substrate, which is different from Example 8 in that the brightness enhancement film described in Comparative Example 4 is used.

将实施例8、对比例8及基准对比例的显示基板采用同样的方式组装为显示面板,仅点亮红光像素,采用与实施例5相同的测试方式,测试显示面板的电压、电流、各个像素的亮度变化及色偏等,测试结果如下表15所示。The display substrates of Example 8, Comparative Example 8 and the benchmark comparative example are assembled into a display panel in the same manner, and only the red pixels are lit. The voltage, current, brightness change and color deviation of each pixel of the display panel are tested in the same test method as Example 5. The test results are shown in Table 15 below.

表15实施例8、对比例8、基准对比例的显示基板弯折前的测试数据Table 15 Test data of display substrates before bending of Example 8, Comparative Example 8 and Benchmark Comparative Example

Figure BDA0004073209810000241
Figure BDA0004073209810000241

由表15可知,在显示面板最终亮度相同的测试条件下,相比基准对比例,对比例8和实施例8中的红色像素的像素亮度变化较小,而像素电流都显著减小,显示面板的电流和功耗都显著降低。由此可知,在显示基板中设置胆甾相液晶层和胆甾相液晶微胶囊层都能提升显示面板的出光效率,并降低显示面板功耗,并且色偏较小。It can be seen from Table 15 that under the test conditions of the same final brightness of the display panel, compared with the reference comparative example, the pixel brightness of the red pixel in comparative example 8 and embodiment 8 changes less, while the pixel current is significantly reduced, and the current and power consumption of the display panel are significantly reduced. It can be seen that the provision of a cholesteric liquid crystal layer and a cholesteric liquid crystal microcapsule layer in the display substrate can improve the light extraction efficiency of the display panel, reduce the power consumption of the display panel, and have a smaller color deviation.

将实施例8、对比例8及基准对比例的显示面板在3mm弯折半径下弯折20万次,继续测试显示面板的电压、电流、各个像素的亮度变化及色偏等,测试结果如下表16所示。The display panels of Example 8, Comparative Example 8 and the benchmark comparative example were bent 200,000 times at a bending radius of 3 mm, and the voltage, current, brightness change and color deviation of each pixel of the display panels were further tested. The test results are shown in Table 16 below.

表16实施例8、对比例8、基准对比例的显示基板弯折后的测试数据Table 16 Test data of display substrates after bending of Example 8, Comparative Example 8 and Benchmark Comparative Example

Figure BDA0004073209810000242
Figure BDA0004073209810000242

由表16可知,与对比例8和基准对比例相比,实施例8的显示基板在弯折前后其各项性能尤其是色偏变化程度很小,说明实施例8的显示基板的抗弯折性能更好,更稳定。这是由于实施例8中使用了增亮膜,其具有良好的抗弯折性能,将其设置在显示基板上,由于增亮膜中的微结构不易流动,稳定性好,可以避免出现因液晶流动造成的显示基板折叠区和非折叠区的液晶分布不均匀导致的光透过率不同的问题,有效提升显示基板的弯折性能。It can be seen from Table 16 that, compared with Comparative Example 8 and the reference comparative example, the display substrate of Example 8 has a small change in various properties, especially color shift, before and after bending, indicating that the display substrate of Example 8 has better and more stable anti-bending performance. This is because a brightness enhancement film is used in Example 8, which has good anti-bending performance. It is set on the display substrate. Since the microstructure in the brightness enhancement film is not easy to flow and has good stability, the problem of different light transmittance caused by uneven distribution of liquid crystal in the folding area and non-folding area of the display substrate caused by liquid crystal flow can be avoided, and the bending performance of the display substrate is effectively improved.

综上所述,本申请提供的增亮膜3及其制备方法、显示基板和显示装置,在增亮膜3中设置含有液晶的微结构层,微结构层中的多个微结构流动性较差,对微结构内的液晶起到了稳定和限流的作用,防止微结构层内的液晶随意流动,导致微结构层内的液晶分布不均匀,进而导致增亮膜3的出光强度及出光效率降低。即使在增亮膜3进行折弯的情况下,由于微结构流动性较差,使得增亮膜3的折叠区和非折叠区内的液晶差别不大,避免出现色偏的问题,提升增亮膜3的出光效率及折弯性能。将所述增亮膜3应用于显示基板时,增亮膜3可以提升显示基板的出光效率,同时由于增亮膜3中的微结构不易流动,稳定性好,可以避免出现因液晶流动造成的显示基板折叠区和非折叠区的液晶分布不均匀导致的光透过率不同的问题,有效提升显示基板的弯折性能。In summary, the brightness enhancement film 3 and its preparation method, display substrate and display device provided by the present application are provided with a microstructure layer containing liquid crystal in the brightness enhancement film 3, and the multiple microstructures in the microstructure layer have poor fluidity, which plays a role in stabilizing and limiting the current of the liquid crystal in the microstructure, preventing the liquid crystal in the microstructure layer from flowing randomly, resulting in uneven distribution of the liquid crystal in the microstructure layer, and then resulting in reduced light output intensity and light output efficiency of the brightness enhancement film 3. Even in the case where the brightness enhancement film 3 is bent, due to the poor fluidity of the microstructure, the liquid crystal in the folding area and the non-folding area of the brightness enhancement film 3 is not much different, avoiding the problem of color deviation, and improving the light output efficiency and bending performance of the brightness enhancement film 3. When the brightness enhancement film 3 is applied to the display substrate, the brightness enhancement film 3 can improve the light output efficiency of the display substrate. At the same time, since the microstructure in the brightness enhancement film 3 is not easy to flow and has good stability, the problem of different light transmittance caused by uneven distribution of liquid crystal in the folding area and non-folding area of the display substrate caused by the flow of liquid crystal can be avoided, and the bending performance of the display substrate is effectively improved.

需要说明的是,上述对本公开的一些实施例进行了描述。其它实施例在所附权利要求书的范围内。在一些情况下,在权利要求书中记载的动作或步骤可以按照不同于上述实施例中的顺序来执行并且仍然可以实现期望的结果。另外,在附图中描绘的过程不一定要求示出的特定顺序或者连续顺序才能实现期望的结果。在某些实施方式中,多任务处理和并行处理也是可以的或者可能是有利的。It should be noted that the above describes some embodiments of the present disclosure. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the above embodiments and still achieve the desired results. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

所属领域的普通技术人员应当理解:以上任何实施例的讨论仅为示例性的,并非旨在暗示本公开的范围(包括权利要求)被限于这些例子;在本公开的思路下,以上实施例或者不同实施例中的技术特征之间也可以进行组合,步骤可以以任意顺序实现,并存在如上所述的本公开实施例的不同方面的许多其它变化,为了简明它们没有在细节中提供。Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present disclosure (including the claims) is limited to these examples. Based on the concept of the present disclosure, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of different aspects of the embodiments of the present disclosure as described above, which are not provided in detail for the sake of simplicity.

本公开实施例旨在涵盖落入所附权利要求的宽泛范围之内的所有这样的替换、修改和变型。因此,凡在本公开实施例的精神和原则之内,所做的任何省略、修改、等同替换、改进等,均应包含在本公开的保护范围之内。The embodiments of the present disclosure are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present disclosure should be included in the scope of protection of the present disclosure.

Claims (15)

1. A brightness enhancing film, comprising: a microstructure layer containing liquid crystal, wherein the microstructure layer contains a plurality of microstructures, and the microstructures contain the liquid crystal.
2. The brightness enhancing film of claim 1 wherein the microstructure is a microcapsule.
3. The brightness enhancing film of claim 1 wherein the liquid crystal is a cholesteric liquid crystal.
4. The brightness enhancing film of claim 1 wherein the microstructured layer comprises a plurality of stacked microstructured sublayers, each having a different reflection band.
5. The brightness enhancing film of claim 1 wherein the microstructured layer has a thickness of from 10 to 60 μm.
6. The brightness enhancing film of claim 1 wherein the microstructured sublayer has a thickness of 1-10 μm.
7. The brightness enhancing film of claim 1 wherein the microstructured layer and microstructured sublayer each have a haze of less than or equal to 3%.
8. The brightness enhancing film of claim 1 wherein the microstructured layer is made from a mixture of microstructures comprising liquid crystals, a polymer monomer, and a photoinitiator.
9. The brightness enhancing film of claim 8 wherein the microstructure comprising liquid crystal is a microcapsule comprising cholesteric liquid crystal comprising a core material and a shell material surrounding the core material, the core material comprising the following components in parts by weight: 65-85% of nematic liquid crystal, 10-30% of left-handed or right-handed cholesteric liquid crystal and 4-5% of chiral additive.
10. A display substrate, comprising:
a substrate comprising a folded region and an unfolded region;
the light-emitting structure layer is arranged on the substrate;
the brightness enhancing film of any one of claims 1 to 9 disposed on a side of the light emitting structure layer remote from the substrate, the orthographic projection of the brightness enhancing film on the substrate covering at least the fold region;
the anti-reflection layer is arranged on one side of the brightness enhancement film away from the substrate.
11. The display substrate according to claim 10, wherein the light emitting structure layer includes a plurality of light emitting regions formed by a plurality of pixel openings defined by the pixel defining layer, the plurality of light emitting regions including a first light emitting region emitting light of a first color, a second light emitting region emitting light of a second color, and a third light emitting region emitting light of a third color;
the micro-structure layer comprises three micro-structure sublayers which are sequentially overlapped, and reflection wave bands of the three micro-structure sublayers are in one-to-one correspondence with the wavelength of the first color light, the wavelength of the second color light and the wavelength of the third color light.
12. The display substrate according to claim 10, wherein the light emitting structure layer includes a plurality of light emitting regions formed by a plurality of pixel openings defined by the pixel defining layer, the plurality of light emitting regions including a first light emitting region emitting light of a first color, a second light emitting region emitting light of a second color, and a third light emitting region emitting light of a third color;
The microstructure layer is a single-layer microstructure sub-layer, and the reflection wave band of the microstructure sub-layer corresponds to the wavelength of the first color light, the wavelength of the second color light or the wavelength of the third color light.
13. A method of preparing a brightness enhancing film comprising:
mixing a microstructure containing liquid crystal, a polymer monomer and a photoinitiator to form a mixed system;
spreading the mixed system to form a mixed system prefabricated film layer, and irradiating the mixed system prefabricated film layer by light to enable a photoinitiator in the mixed system to initiate a polymer monomer to perform a polymerization reaction so as to obtain the brightness enhancement film.
14. The method of claim 13, wherein the spreading the mixed system to form a mixed system pre-formed film layer comprises:
spreading the mixed system on the surface of a substrate, and forming a mixed system prefabricated film layer on the surface of the substrate; or, the mixed system is put into a transparent box-like body, the mixed system is spread in the transparent box-like body, and the mixed system pre-film layer is formed in the transparent box-like body.
15. A display device comprising the display substrate according to any one of claims 10 to 12, wherein the display substrate is an organic light emitting diode display substrate.
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