WO2013185383A1 - 一种平面切换模式液晶显示面板及其制备工艺和显示器 - Google Patents

一种平面切换模式液晶显示面板及其制备工艺和显示器 Download PDF

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WO2013185383A1
WO2013185383A1 PCT/CN2012/077736 CN2012077736W WO2013185383A1 WO 2013185383 A1 WO2013185383 A1 WO 2013185383A1 CN 2012077736 W CN2012077736 W CN 2012077736W WO 2013185383 A1 WO2013185383 A1 WO 2013185383A1
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Prior art keywords
liquid crystal
substrate
alignment film
transparent electrode
frequency
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PCT/CN2012/077736
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English (en)
French (fr)
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马小龙
黄宏基
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深圳市华星光电技术有限公司
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Priority to US13/638,078 priority Critical patent/US9170460B2/en
Publication of WO2013185383A1 publication Critical patent/WO2013185383A1/zh

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    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1337—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers
    • G02F1/133711—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers by organic films, e.g. polymeric films
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1337—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers
    • G02F1/133711—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers by organic films, e.g. polymeric films
    • G02F1/133715—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers by organic films, e.g. polymeric films by first depositing a monomer
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1337—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers
    • G02F1/133765—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers without a surface treatment
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1343—Electrodes
    • G02F1/134309—Electrodes characterised by their geometrical arrangement
    • G02F1/134363—Electrodes characterised by their geometrical arrangement for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F2202/00—Materials and properties
    • G02F2202/02—Materials and properties organic material
    • G02F2202/022—Materials and properties organic material polymeric
    • G02F2202/023—Materials and properties organic material polymeric curable

Definitions

  • the present invention relates to a liquid crystal panel, and more particularly to a planar switching mode liquid crystal display panel and a preparation process thereof, and a display using the liquid crystal display panel.
  • the liquid crystal display includes a liquid crystal panel having an upper substrate and a lower substrate, and transparent electrodes disposed on opposite sides of the upper and lower substrates, and a layer of liquid crystal molecules disposed between the substrates.
  • the liquid crystal display is an electric field generated by a transparent electrode, controls the orientation of the liquid crystal molecules, thereby changing the polarization state of the light, and realizes the purpose of display by the penetration and blocking of the optical path by the polarizing plate.
  • the main technical parameters for evaluating liquid crystal displays are: 1 contrast, 2 brightness, 3 signal response time, and 4 viewing angles.
  • the parameters of contrast, brightness and viewing angle are mainly determined by the liquid crystal panel.
  • the viewing angle has always been the focus and difficulty of liquid crystal panel research. This is because when the backlight passes through the polarizer, liquid crystal and alignment film, the output light has directionality. That is to say, most of the light is emitted vertically from the screen, so when you look at the LCD panel from an oblique angle, you can't see the original color, or even see all white or all black.
  • a planar switching mode In-Plane). –Switching, IPS) LCD panel.
  • the liquid crystal molecules in the liquid crystal layer are positive liquid crystals, and the transparent electrodes are disposed on the lower substrate.
  • the long-axis parallel substrates of the liquid crystal molecules are arranged without optical delay, and a darker darkness can be obtained. State; the liquid crystal molecules rotate horizontally during power-on to pass incident polarized light, which is normally black (Normally Black).
  • the IPS mode features high contrast and high-speed response, and is often used in applications such as televisions.
  • the present invention provides a novel IPS mode liquid crystal display panel preparation method, which can overcome the pollution and static electricity problems caused by the rubbing alignment in the preparation process of the IPS mode, and has a simple process, and the obtained liquid crystal panel and liquid crystal are obtained.
  • the display features high contrast, high response speed and wide viewing angle.
  • the first object of the present invention is to provide a preparation process of an IPS mode liquid crystal display panel, which can overcome the pollution and static electricity problems caused by the rubbing alignment in the preparation process of the IPS mode, and has a simple process, and the obtained liquid crystal panel is obtained. And the LCD display has high contrast, high response speed and wide viewing angle.
  • a second object of the present invention is to provide a planar switching mode liquid crystal display panel
  • a third object of the present invention is to provide a liquid crystal display
  • the dual-frequency liquid crystal molecules and the dual-frequency reactive monomer with dual-frequency characteristics are utilized, and the dual-frequency characteristics of the two are used to drive the high-frequency alternating electric field in the alignment process, so that the dual-frequency liquid crystal molecules and the dual-frequency reactive monomers are
  • the substrate is subjected to an action of the alignment film on one side surface of the liquid crystal layer to generate a pretilt angle, and the liquid crystal layer is irradiated by UV light, and the double-frequency reactive monomer maintaining the pretilt angle is reacted and solidified on the surface to complete the alignment process.
  • the dual-frequency liquid crystal molecules and the dual-frequency reactive monomer can be driven using a low-frequency alternating electric field.
  • a preparation process of a planar switching mode liquid crystal display panel comprising the following steps:
  • the coplanar transparent electrode layer Forming a coplanar transparent electrode layer on the second alignment film of the second substrate, the coplanar transparent electrode layer comprising at least two transparent electrodes, wherein the transparent electrodes have slits therebetween;
  • liquid crystal composition between the first substrate and the second substrate to form a liquid crystal layer contacting the first alignment film, the coplanar transparent electrode layer, and the second of the slits
  • liquid crystal composition comprises a dual frequency liquid crystal molecule and a dual frequency reactive monomer
  • a liquid crystal display panel is formed after attaching a polarizer to the other side surface of the first and second substrates corresponding to the liquid crystal layer.
  • the at least two coplanar transparent electrodes are disposed in parallel, respectively spanning the second substrate.
  • the frequency range of the high frequency alternating electric field is between 1000 Hz and 10000 Hz.
  • the coplanar transparent electrode layer is made of indium tin oxide (Indium Tin Oxide, Made of ITO).
  • the first substrate is a color filter substrate
  • the second substrate is a thin film transistor (Thin Film) Transistor, TFT) array substrate.
  • a preparation process of a planar switching mode liquid crystal display panel including the following steps:
  • coplanar transparent electrode layer made of indium tin oxide on the second alignment film of the second substrate, the coplanar transparent electrode layer comprising at least two transparent electrodes disposed in parallel, the transparent electrode Having a slit therebetween and respectively spanning the second substrate;
  • liquid crystal composition between the first substrate and the second substrate to form a liquid crystal layer contacting the first alignment film, the coplanar transparent electrode layer, and the second of the slits
  • liquid crystal composition comprises a dual frequency liquid crystal molecule and a dual frequency reactive monomer
  • a high-frequency alternating electric field having a frequency ranging from 1000 Hz to 10000 Hz is applied between the adjacent transparent electrodes, so that the long axis of the liquid crystal composition is aligned in a vertical electric field direction and a pretilt angle is formed; and ultraviolet ray irradiation is performed to complete the liquid crystal alignment.
  • a liquid crystal display panel is formed after attaching a polarizer to the other side surface of the liquid crystal composition on the first and second substrates.
  • the first substrate is a color filter substrate
  • the second substrate is a thin film transistor array substrate.
  • a second object of the present invention is to provide a planar switching mode liquid crystal display panel, comprising:
  • the coplanar transparent electrode layer disposed on the second alignment film of the second substrate, the coplanar transparent electrode layer comprising at least two transparent electrodes, wherein the transparent electrodes have slits therebetween;
  • liquid crystal layer interposed between the first alignment film side of the first substrate and the coplanar transparent electrode layer side of the second substrate, the liquid crystal layer comprising a dual-frequency liquid crystal molecule and a dual-frequency reactive single Body liquid crystal composition;
  • a plurality of liquid crystal compositions having a pretilt angle are arranged on the side surface of the first alignment film and the coplanar transparent electrode layer corresponding to the liquid crystal layer, respectively.
  • the at least two coplanar transparent electrodes are disposed in parallel, respectively spanning the second substrate.
  • the coplanar transparent electrode layer is made of ITO.
  • the first substrate is a color filter substrate
  • the second substrate is a TFT array substrate
  • a planar switching mode liquid crystal display panel including:
  • a coplanar transparent electrode layer made of indium tin oxide, disposed on the second alignment film of the second substrate, the coplanar transparent electrode layer comprising at least two transparent electrodes disposed in parallel, the transparent electrode Having a slit therebetween and respectively spanning the second substrate;
  • liquid crystal layer interposed between the first alignment film side of the first substrate and the coplanar transparent electrode layer side of the second substrate, the liquid crystal layer comprising a dual-frequency liquid crystal molecule and a dual-frequency reactive single Body liquid crystal composition;
  • a plurality of liquid crystal compositions having a pretilt angle are arranged on the side surface of the first alignment film and the coplanar transparent electrode layer corresponding to the liquid crystal layer, respectively.
  • the first substrate is a color filter substrate
  • the second substrate is a thin film transistor array substrate.
  • a third object of the present invention is to provide a liquid crystal display comprising any one of the above liquid crystal panels and a backlight module.
  • the backlight module of the present invention is not particularly limited, and a backlight module of the existing IPS mode liquid crystal display can be used.
  • dual-frequency liquid crystal molecules refer to liquid crystal molecules (or reactive monomers) having dual-frequency characteristics
  • dual-frequency characteristics refer to: dual-frequency liquid crystal molecules ( The characteristics of the double-frequency reactive monomer as a function of the direction of the electric field change with the change of the driving frequency.
  • the long-axis direction of the dual-frequency liquid crystal molecules is aligned perpendicular to the direction of the electric field, exhibiting negative liquid crystal characteristics; when driven by a low-frequency alternating electric field, the dual-frequency liquid crystal The long axis of the molecule (or dual-frequency reactive monomer) is aligned parallel to the direction of the electric field, exhibiting positive liquid crystal properties.
  • the invention utilizes the dual-frequency characteristics of the dual-frequency liquid crystal molecules and the dual-frequency reactive monomers, combined with the coplanar transparent electrode arrangement, and is driven by a high-frequency alternating electric field in the alignment stage, so that the dual-frequency liquid crystal molecules and the dual-frequency reactive monomers are
  • the substrate is subjected to the action of the alignment film on one side surface of the liquid crystal layer to generate a pretilt angle, and then the dual-frequency reactive monomer maintaining the pretilt angle is reacted and solidified on the surface by UV light irradiation to complete the alignment process;
  • the dual-frequency liquid crystal molecules and the dual-frequency reactive monomer can be driven by driving with a low-frequency alternating electric field.
  • the liquid crystal display panel of the invention and the liquid crystal display comprising the same have the characteristics of high contrast, high response speed and wide viewing angle of the IPS mode liquid crystal display, and overcome the pollution and static electricity caused by the frictional alignment in the IPS mode.
  • the problem is that the process is simple and the preparation process is saved.
  • 1 is a distribution state of dual-frequency liquid crystal molecules and dual-frequency reactive monomers in an IPS mode liquid crystal display panel in an electric field according to an embodiment of the present invention
  • Figure 2 is a plan view of the second substrate of Figure 1;
  • FIG. 3 is a view showing a distribution state of dual-frequency liquid crystal molecules and dual-frequency reactive monomers in an alignment process of an IPS mode liquid crystal display panel according to an embodiment of the present invention. among them:
  • 10 is a first substrate; 20 is a first alignment film;
  • 50 is a coplanar transparent electrode layer; 501 is a transparent electrode; 502 is a slit between transparent electrodes;
  • 70 is a first polarizer; 80 is a second polarizer.
  • FIG. 1 is a cross-sectional view showing an IPS mode liquid crystal display panel of the present embodiment when an electric field is applied.
  • the liquid crystal panel includes a first substrate 10, a second substrate 30, and a first substrate.
  • the first substrate 10 is a color filter (Color Filter, CF) substrate
  • the second substrate 30 is a TFT array substrate.
  • the first substrate 10 and the second substrate 30 are disposed opposite to each other.
  • a first alignment film 20 is disposed on a surface of the first substrate 10 corresponding to the liquid crystal layer 60, and a second alignment film 40 is disposed on a surface of the second substrate 30 corresponding to the liquid crystal layer 60.
  • the coplanar transparent electrode layer 50 is made of ITO, and is disposed on the second alignment film 40 of the second substrate 30.
  • the coplanar transparent electrode layer 50 includes at least two transparent electrodes 501 placed in parallel with each other.
  • the transparent electrode 501 has a slit 502 therebetween.
  • the coplanar transparent electrode layer 50 includes three transparent electrodes 501 placed in parallel with each other.
  • the liquid crystal layer 60 is interposed between the first alignment film 20 side of the first substrate 10 and the coplanar transparent electrode layer 50 side of the second substrate 30, and includes a dual-frequency liquid crystal molecule 601 and a dual-frequency reaction.
  • the liquid crystal composition of the monomer 602 is composed.
  • the first polarizer 70 is located on the other side surface of the first substrate 10 corresponding to the liquid crystal layer 60, and the second polarizer 80 is located at the corresponding liquid crystal layer 60 of the second substrate 30. On the other side of the surface.
  • FIG. 2 is a top view of the second substrate 30 shown in FIG. 1.
  • the transparent electrodes 501 are disposed in parallel in parallel, respectively spanning the second substrate 30.
  • the embodiment further provides a preparation process of the above IPS mode liquid crystal display panel, including the following steps:
  • the first substrate 10 and the second substrate 30 are provided.
  • the first substrate 10 is a CF substrate
  • the second substrate 30 is a TFT array substrate
  • the first and second substrates 10 and 30 are prepared by a conventional method in the art. , no longer detailed here;
  • a first alignment film 20 is formed on the first substrate 10, and a second alignment film 40 is formed on the second substrate 20.
  • the method for forming the first and second alignment films 20 and 40 is conventional in the art. Method, not detailed here;
  • the coplanar transparent electrode layer 50 Forming a coplanar transparent electrode layer 50 on the second alignment film 40 of the second substrate 30, the coplanar transparent electrode layer 50 comprising at least two transparent electrodes 501 placed in parallel with each other, between the transparent electrodes 501 There is a slit 502.
  • the coplanar transparent electrode layer 50 includes three transparent electrodes 501 placed in parallel with each other across the second substrate 30.
  • the transparent electrode 501 is an ITO electrode, and the method for forming the transparent electrode adopts a conventional method in the art, which will not be described in detail herein;
  • a liquid crystal composition composed of a dual-frequency liquid crystal molecule 601 and a dual-frequency reactive monomer 602 is filled between the first substrate 10 and the second substrate 30 to form a liquid crystal layer 60, and the liquid crystal layer 60 contacts the a first alignment film 20, the coplanar transparent electrode layer 50, and a surface of the second alignment film 40 of the slit 502;
  • first and second polarizers 70 and 80 are attached to the other side surfaces of the first and second substrates 10 and 30 corresponding to the liquid crystal layer 60, a liquid crystal display panel is formed.
  • FIG. 3 shows the alignment process in the present embodiment.
  • the dual-frequency reactive monomer 602 is polymerized and cured in the first alignment film 20 and coplanar transparent by UV light irradiation.
  • the electrode layer 50 corresponds to one side surface of the liquid crystal layer 60.
  • the dual-frequency reactive monomer 602 is moved to the first alignment film 20 and the coplanar transparent electrode layer by the action of the electric field and the anchoring force of the alignment film during the irradiation of the UV light.
  • the 50 surface has a certain directionality, which is the so-called pretilt angle, and is then irradiated by UV light to cure the pretilt angle of the dual frequency reactive monomer 602. At this point, the alignment process is completed.
  • a low-frequency alternating electric field with a frequency of ⁇ 250 Hz is applied between adjacent transparent electrodes 501 of the second substrate 30. Due to the dual-frequency characteristic, the dual-frequency liquid crystal molecules 601 and the dual-frequency reactivity at this time The long-axis direction of the cell 602 exhibits a characteristic parallel to the electric field arrangement, and the magnitude of the deflection angle of the dual-frequency liquid crystal molecule 601 and the dual-frequency reactive cell 602 at this time is determined by the magnitude of the electric field. The magnitude of the deflection angle of the dual-frequency liquid crystal molecule 601 and the dual-frequency reactive monomer 602 determines the efficiency of light passage, and different gray scales can be generated by different deflection angles, thereby achieving the purpose of development.
  • the invention utilizes the dual-frequency liquid crystal molecules and the dual-frequency reactive monomer dual-frequency characteristics, combined with the coplanar transparent electrode arrangement, and is driven by a high-frequency alternating electric field in the alignment stage, so that the dual-frequency liquid crystal molecules and the dual-frequency reactive monomers are
  • the substrate is subjected to the action of the alignment film on one side surface of the liquid crystal layer to generate a pretilt angle, and then the dual-frequency reactive monomer maintaining the pretilt angle is reacted and cured on the surface of the first alignment film and the coplanar surface by UV light irradiation.
  • the surface of the transparent electrode layer completes the alignment process; and when the liquid crystal display panel of the present invention is driven, the dual-frequency liquid crystal molecules and the dual-frequency reactive monomer can be driven by using a low-frequency alternating electric field drive.
  • the liquid crystal display panel of the invention and the liquid crystal display comprising the same have the characteristics of high contrast, high response speed and wide viewing angle of the IPS mode liquid crystal display, and overcome the pollution and static electricity caused by the frictional alignment in the IPS mode. The problem is that the process is simple and the preparation process is saved.

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  • Nonlinear Science (AREA)
  • Spectroscopy & Molecular Physics (AREA)
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Abstract

一种平面切换（In-Plane-Switching，IPS）模式液晶显示面板，包括：一第一基板（10）、一第二基板（30）、一共面透明电极层（50）和一液晶层（60）。所述第一、第二基板（10，30）分别具有一第一配向膜（20）及一第二配向膜（40）。所述共面透明电极层（50）设于第二配向膜（40）上。所述液晶层（60）夹设于第一基板（10）的第一配向膜（20）侧和第二基板（30）的共面透明电极层（50）侧之间，其中液晶层（60）包含双频液晶分子（601）和双频反应性单体（602）。该液晶显示面板既可以克服IPS模式制备过程中摩擦配向所带来的污染及静电问题，又工序简单，使所制得的液晶面板和液晶显示器具有高对比度、高响应速度和宽可视角度等特点。

Description

一种平面切换模式液晶显示面板及其制备工艺和显示器 技术领域
本发明涉及一种液晶面板，特别是涉及一种平面切换模式液晶显示面板及其制备工艺，以及应用该液晶显示面板的显示器。
 背景技术
液晶显示器包含液晶面板和背光模组，所述液晶面板具有上基板和下基板，在所述上下基板的相对内侧分别配置有透明电极，基板之间配置有一层液晶分子。液晶显示器是通过透明电极产生的电场，对液晶分子的取向进行控制，从而改变光的偏振状态，并藉由偏光板实现光路的穿透与阻挡，实现显示的目的。
评价液晶显示器的主要技术参数有：①对比度、②亮度、③信号响应时间、④可视角度。其中，对比度、亮度和可视角度的参数主要是取决于液晶面板。可视角度一直是液晶面板研究的重点和难点，这是由于当背光源通过偏极片、液晶和配向膜之后，输出的光线便具有了方向性。也就是说，大多数光都是从屏幕中垂直射出来的，所以从某一个斜角度观看液晶面板时，便不能看到原本的颜色，甚至只能看到全白或全黑。为了解决这个问题，研发人员研发了平面切换模式（In-Plane –Switching, IPS）的液晶显示平板。
在IPS模式的液晶显示面板中，液晶层中的液晶分子是正性液晶，透明电极配置于下基板，不加电时，液晶分子的长轴平行基板排列，无光学延迟，可以得到比较黑的暗态；加电时液晶分子水平旋转使入射偏振光通过，是常黑（Normally black）。IPS模式具有对比度高，高速响应的特点，常用于电视机等应用。但是，在IPS模式的液晶面板制备过程中，需要对基板进行摩擦，来对液晶分子进行初始配向。而这种摩擦配向会带来污染性问题，造成良率的下降，还会有静电等问题，对晶体管造成击伤。
因此，本发明提供一种新的IPS模式液晶显示面板的制备方法，既可以克服IPS模式制备过程中摩擦配向所带来的污染及静电问题，又工序简单，使所制得的液晶面板和液晶显示器具有高对比度、高响应速度和宽可视角度等特点。
 技术问题
本发明的第一个目的是提供一种IPS模式液晶显示面板的制备工艺，既可以克服IPS模式制备过程中摩擦配向所带来的污染及静电问题，又工序简单，使所制得的液晶面板和液晶显示器具有高对比度、高响应速度和宽可视角度等特点。
本发明的第二个目的是提供一种平面切换模式液晶显示面板
本发明的第三个目的是提供一种液晶显示器
 技术解决方案
应用具有双频特性的双频液晶分子和双频反应性单体，利用两者的双频特性，在配向过程中使用高频交流电场驱动，使双频液晶分子和双频反应性单体在基板对应液晶层的一侧表面上受配向膜的作用而产生预倾角，通过UV光照射液晶层，使维持预倾角的双频反应性单体反应固化在所述表面，完成配向过程。在驱动本发明的液晶显示面板时，使用低频交流电场，就可以驱动所述双频液晶分子和所述双频反应性单体。
为实现上述目的，本发明公开以下技术方案：一种平面切换模式液晶显示面板的制备工艺，包括以下步骤：
提供一第一基板和一第二基板，在所述第一基板上形成一第一配向膜，在所述第二基板上形成一第二配向膜；
在所述第二基板的第二配向膜上形成一共面透明电极层，所述共面透明电极层包含至少两个透明电极，所述透明电极之间具有狭缝；
将液晶组合物填充入所述第一基板与第二基板之间，形成一液晶层，所述液晶层接触所述第一配向膜、所述共面透明电极层和所述狭缝中第二配向膜，其中所述液晶组合物包含双频液晶分子和双频反应性单体；
在相邻的所述透明电极之间施加高频交流电场，使得液晶组合物的分子长轴垂直电场方向排列并形成预倾角；同时进行紫外线照射，完成液晶配向；以及
分别在所述第一、第二基板对应所述液晶层的另一侧表面上贴附偏光片后，形成液晶显示面板。
在本发明一实施例中，所述至少两个共面透明电极平行设置，分别横跨所述第二基板。
在本发明一实施例中，所述高频交流电场的频率范围在1000Hz~10000Hz之间。
在本发明一实施例中，所述共面透明电极层由铟锡氧化物（Indium Tin Oxide , ITO）制成。
在本发明一实施例中，所述第一基板为彩色滤光片基板，所述第二基板为薄膜晶体管（Thin Film Transistor，TFT）阵列基板。
在本发明一较佳实施例中，提供一种平面切换模式液晶显示面板的制备工艺，包括以下步骤：
提供一第一基板和一第二基板，在所述第一基板上形成一第一配向膜，在所述第二基板上形成一第二配向膜；
在所述第二基板的第二配向膜上形成一由铟锡氧化物制成的共面透明电极层，所述共面透明电极层包含至少两个平行设置的透明电极，所述透明电极之间具有狭缝，并分别横跨所述第二基板；
将液晶组合物填充入所述第一基板与第二基板之间，形成一液晶层，所述液晶层接触所述第一配向膜、所述共面透明电极层和所述狭缝中第二配向膜，其中所述液晶组合物包含双频液晶分子和双频反应性单体；
在相邻的所述透明电极之间施加频率范围在1000Hz~10000Hz之间的高频交流电场，使得液晶组合物的分子长轴垂直电场方向排列并形成预倾角；同时进行紫外线照射，完成液晶配向；以及
分别在所述第一、第二基板对应所述液晶组合物的另一侧表面上贴附偏光片后，形成液晶显示面板。
优选地，所述第一基板为彩色滤光片基板，所述第二基板为薄膜晶体管阵列基板。
本发明的第二个目的是提供一种平面切换模式液晶显示面板，包括：
一第一基板，具有一第一配向膜；
一第二基板，具有一第二配向膜；
一共面透明电极层，设于所述第二基板的第二配向膜上，所述共面透明电极层包含至少两个透明电极，所述透明电极之间具有狭缝；以及
一液晶层，夹设于所述第一基板的第一配向膜侧和所述第二基板的共面透明电极层侧之间，所述液晶层由包含双频液晶分子和双频反应性单体的液晶组合物构成；
在所述第一配向膜和共面透明电极层对应液晶层的一侧表面上分别具有多個排列预倾角的液晶组合物。
在本发明一实施例中，所述至少两个共面透明电极平行设置，分别横跨所述第二基板。
在本发明一实施例中，所述共面透明电极层由ITO制成。
在本发明一实施例中，所述第一基板为彩色滤光片基板，所述第二基板为TFT阵列基板。
在本发明一较佳实施例中，提供一种平面切换模式液晶显示面板，包括：
一第一基板，具有一第一配向膜；
一第二基板，具有一第二配向膜；
一共面透明电极层，由铟锡氧化物制成，设于所述第二基板的第二配向膜上，所述共面透明电极层包含至少两个平行设置的透明电极，所述透明电极之间具有狭缝，并分别横跨所述第二基板；以及
一液晶层，夹设于所述第一基板的第一配向膜侧和所述第二基板的共面透明电极层侧之间，所述液晶层由包含双频液晶分子和双频反应性单体的液晶组合物构成；
在所述第一配向膜和共面透明电极层对应液晶层的一侧表面上分别具有多個排列预倾角的液晶组合物。
优选地，所述第一基板为彩色滤光片基板，所述第二基板为薄膜晶体管阵列基板。
本发明的第三个目的是提供一种液晶显示器，包括上述任意一种液晶面板及背光模组。本发明对于所述的背光模组没有特别限定，可以使用现有IPS模式液晶显示器的背光模组。
需要说明的是，所述双频液晶分子（或双频反应性单体）是指具有双频特性的液晶分子（或反应性单体），所述双频特性是指：双频液晶分子（或双频反应性单体）随电场方向排列的特性会随着驱动频率的变化而发生改变。例如，在高频交流电场驱动时，双频液晶分子（或双频反应性单体）的长轴方向会垂直于电场方向排列，呈现负性液晶特性；在低频交流电场驱动时，双频液晶分子（或双频反应性单体）的长轴会平行于电场方向排列，呈现正性液晶特性。
 有益效果
本发明利用双频液晶分子和双频反应性单体的双频特性，结合共面透明电极排布，在配向阶段使用高频交流电场驱动，使双频液晶分子和双频反应性单体在基板对应液晶层的一侧表面上受配向膜的作用而产生预倾角，然后通过UV光照射使维持预倾角的双频反应性单体反应固化在所述表面，完成配向过程；而在驱动本发明的液晶显示面板时，使用低频交流电场驱动，就可以驱动所述双频液晶分子和所述双频反应性单体。本发明的液晶显示面板及包含该面板的液晶显示器既具有IPS模式液晶显示器的高对比度、高响应速度和宽可视角度等特点，又克服了IPS模式中由于摩擦配向所带来的污染及静电问题，同时工序简单，节约了制备工序。
 附图说明
图1是本发明一实施例中的IPS模式液晶显示面板在加电场时的双频液晶分子和双频反应性单体的分布状态；
图2是图1中第二基板的俯视图；
图3是本发明一实施例中的IPS模式液晶显示面板在配向过程中的双频液晶分子和双频反应性单体的分布状态。其中：
10为第一基板；20为第一配向膜；
30为第二基板；40为第二配向膜
50为共面透明电极层；501为透明电极；502为透明电极间的狭缝；
60为液晶层；601为双频液晶分子；602为双频反应性单体；
70为第一偏光片；80为第二偏光片。
 本发明的最佳实施方式
以下结合实施例对本发明做详细的说明，实施例旨在解释而非限定本发明的技术方案。再者，本发明所提到的方向用语，例如「上」、「下」、「前」、「后」、「左」、「右」、「内」、「外」、「侧面」等，仅是参考附加图式的方向。因此，使用的方向用语是用以说明及理解本发明，而非用以限制本发明。
请参见附图1，附图1所示的是本实施例的一种IPS模式液晶显示面板在加电场时的剖视图，所述液晶面板包括：一第一基板10，一第二基板30、一第一配向膜20、一第二配向膜40、一共面透明电极50、一液晶层60、一第一偏光片70和一第二偏光片80。其中，所述第一基板10为彩色滤光片（Color Filter，CF）基板；所述第二基板30为TFT阵列基板。所述第一基板10与所述第二基板30为相对设置。所述第一基板10对应液晶层60的一侧表面上设置有一第一配向膜20，所述第二基板30对应液晶层60的一侧表面上设置有一第二配向膜40。所述共面透明电极层50是由ITO制成，设于所述第二基板30的第二配向膜40上，所述共面透明电极层50包含至少两个共面平行放置的透明电极501，所述透明电极501之间具有狭缝502，如附图1所示的，在本实施例中，所述共面透明电极层50包含三个共面平行放置的所述透明电极501。所述液晶层60夹设于所述第一基板10的第一配向膜20侧和所述第二基板30的共面透明电极层50侧之间，由包含双频液晶分子601和双频反应性单体602的液晶组合物构成。所述第一偏光片70位于所述第一基板10的对应所述液晶层60的另一侧表面上，而所述第二偏光片80位于所述第二基板30的对应所述液晶层60的另一侧表面上。
请参见附图2，附图2是附图1中所述第二基板30的俯视图，所述透明电极501共面平行设置，分别横跨所述第二基板30。
本实施例还提供上述IPS模式液晶显示面板的制备工艺流程，包括以下步骤：
提供第一基板10和第二基板30，所述第一基板10为CF基板，所述第二基板30为TFT阵列基板，上述第一、第二基板10、30的制备方法采用本领域常规方法，此处不再详述；
在所述第一基板10上形成第一配向膜20，在所述第二基板20上形成第二配向膜40，形成所述第一、第二配向膜20、40的形成方法采用本领域常规方法，此处不再详述；
在所述第二基板30的第二配向膜40上形成一共面透明电极层50，所述共面透明电极层50包含至少两个共面平行放置的透明电极501，所述透明电极501之间具有狭缝502。在本实施例中，所述共面透明电极层50包含三个共面平行放置的透明电极501，分别横跨所述第二基板30。所述透明电极501为ITO电极，形成透明电极的方法采用本领域常规方法，此处不再详述；
将由双频液晶分子601和双频反应性单体602所构成的液晶组合物填充入所述第一基板10与第二基板30之间，构成一液晶层60，所述液晶层60接触所述第一配向膜20、所述共面透明电极层50和所述狭缝502中第二配向膜40的表面；
在相邻的所述透明电极501之间施加频率≥1000Hz的高频交流电场，同时进行UV照射，完成液晶配向；以及
分别在所述第一、第二基板10和30对应所述液晶层60的另一侧表面上贴附第一、第二偏光片70和80后，形成液晶显示面板。
请继续参见附图2，在所述第二基板30的相邻透明电极501上施加频率范围在1000Hz~10000Hz之间的高频交流电场时，所述双频液晶分子601与双频反应性单体 602的长轴方向表现为垂直于电场排列的特性。请参见附图3，附图3所示的是本实施例中的配向过程，通过UV光照射，使双频反应性单体602发生聚合反应固化在所述第一配向膜20和共面透明电极层50对应液晶层60的一侧表面。由于在UV光照射过程中，始终处于加电状态，因此，双频反应性单体602受电场的作用以及配向膜的锚定力而移动到所述第一配向膜20和共面透明电极层50表面时会有一定的方向性，这个方向性就是通常所说的预倾角，而后通过UV光照射以固化所述双频反应性单体602的预倾角。至此，完成了配向过程。
在正式驱动液晶面板工作阶段，在所述第二基板30的相邻透明电极501之间加上频率≤250Hz的低频交流电场，由于双频特性，此时双频液晶分子601与双频反应性单体602的长轴方向表现为平行于电场排列的特性，而此时双频液晶分子601与双频反应性单体602偏转角度的大小由电场大小决定。而双频液晶分子601与双频反应性单体602的偏转角度的大小决定了光通过的效率，通过不同的偏转角度可以产生不同的灰阶，从而实现显像的目的。
本发明利用上述双频液晶分子和双频反应性单体双频特性，结合共面透明电极排布，在配向阶段使用高频交流电场驱动，使双频液晶分子和双频反应性单体在基板对应液晶层的一侧表面上受配向膜的作用而产生预倾角，然后通过UV光照射使维持预倾角的双频反应性单体反应固化在所述第一配向膜表面和所述共面透明电极层表面，完成配向过程；而在驱动本发明的液晶显示面板时，使用低频交流电场驱动，就可以驱动所述双频液晶分子和所述双频反应性单体。本发明的液晶显示面板及包含该面板的液晶显示器既具有IPS模式液晶显示器的高对比度、高响应速度和宽可视角度等特点，又克服了IPS模式中由于摩擦配向所带来的污染及静电问题，同时工序简单，节约了制备工序。
本发明已由上述相关实施例加以描述，然而上述实施例仅为实施本发明的范例。必需指出的是，已公开的实施例并未限制本发明的范围。相反地，包含于权利要求书的精神及范围的修改及均等设置均包括于本发明的范围内。
 本发明的实施方式
工业实用性
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Claims (12)

  1. 一种平面切换模式液晶显示面板的制备工艺，所述制备工艺流程包括以下步骤：
    提供一第一基板和一第二基板，在所述第一基板上形成一第一配向膜，在所述第二基板上形成一第二配向膜；
    在所述第二基板的第二配向膜上形成一共面透明电极层，所述共面透明电极层包含至少两个透明电极，所述透明电极之间具有狭缝；
    将液晶组合物填充入所述第一基板与第二基板之间，形成一液晶层，所述液晶层接触所述第一配向膜、所述共面透明电极层和所述狭缝中第二配向膜，其中所述液晶组合物包含双频液晶分子和双频反应性单体；
    在相邻的所述透明电极之间施加高频交流电场，使得液晶组合物的分子长轴垂直电场方向排列并形成预倾角；同时进行紫外线照射，完成液晶配向；以及
    分别在所述第一、第二基板对应所述液晶组合物的另一侧表面上贴附偏光片后，形成液晶显示面板。
  2. 根据权利要求1所述的制备工艺，其中，所述至少两个共面透明电极平行设置，分别横跨所述第二基板。
  3. 根据权利要求1或2所述的制备工艺，其中，所述高频交流电场的频率范围在1000Hz~10000Hz之间。
  4. 根据权利要求1或2所述的制备工艺，其中，所述共面透明电极层由铟锡氧化物制成。
  5. 根据权利要求1或2所述的制备工艺，其中，所述第一基板为彩色滤光片基板，所述第二基板为薄膜晶体管阵列基板。
  6. 一种平面切换模式液晶显示面板的制备工艺，所述制备工艺流程包括以下步骤：
    提供一第一基板和一第二基板，在所述第一基板上形成一第一配向膜，在所述第二基板上形成一第二配向膜；
    在所述第二基板的第二配向膜上形成一由铟锡氧化物制成的共面透明电极层，所述共面透明电极层包含至少两个平行设置的透明电极，所述透明电极之间具有狭缝，并分别横跨所述第二基板；
    将液晶组合物填充入所述第一基板与第二基板之间，形成一液晶层，所述液晶层接触所述第一配向膜、所述共面透明电极层和所述狭缝中第二配向膜，其中所述液晶组合物包含双频液晶分子和双频反应性单体；
    在相邻的所述透明电极之间施加频率范围在1000Hz~10000Hz之间的高频交流电场，使得液晶组合物的分子长轴垂直电场方向排列并形成预倾角；同时进行紫外线照射，完成液晶配向；以及
    分别在所述第一、第二基板对应所述液晶组合物的另一侧表面上贴附偏光片后，形成液晶显示面板。
  7. 根据权利要求6所述的制备工艺，其中，所述第一基板为彩色滤光片基板，所述第二基板为薄膜晶体管阵列基板。
  8. 一种平面切换模式液晶显示面板，所述液晶显示面板包括：
    一第一基板，具有一第一配向膜；
    一第二基板，具有一第二配向膜；
    一共面透明电极层，设于所述第二基板的第二配向膜上，所述共面透明电极层包含至少两个透明电极，所述透明电极之间具有狭缝；以及
    一液晶层，夹设于所述第一基板的第一配向膜侧和所述第二基板的共面透明电极层侧之间，所述液晶层由包含双频液晶分子和双频反应性单体的液晶组合物构成；
    在所述第一配向膜和共面透明电极层对应液晶层的一侧表面上分别具有多個排列预倾角的液晶组合物。
  9. 根据权利要求8所述的液晶显示面板，其中，所述至少两个共面透明电极平行设置，分别横跨所述第二基板。
  10. 根据权利要求8或9所述的液晶显示面板，其中，所述共面透明电极层由铟锡氧化物制成。
  11. 根据权利要求8或9所述的液晶显示面板，其中，所述第一基板为彩色滤光片基板，所述第二基板为薄膜晶体管阵列基板。
  12. 权利要求8~11中任一所述液晶面板在液晶显示器中的应用。
PCT/CN2012/077736 2012-06-15 2012-06-28 一种平面切换模式液晶显示面板及其制备工艺和显示器 WO2013185383A1 (zh)

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