KR101943658B1 - Liquid Crystal Display Device - Google Patents

Abstract

A liquid crystal display device is provided. A liquid crystal display device includes a first substrate, a second substrate facing away from the first substrate, a liquid crystal layer disposed between the first and second substrates, a first substrate and a liquid crystal layer, and a second electrode disposed between the liquid crystal layer and the second substrate and having a second slit, wherein the liquid crystal layer is a nematic liquid crystal having a negative dielectric anisotropy, a liquid crystal layer having a positive dielectric anisotropy Nematic liquid crystals and ferroelectric liquid crystals.

Description

[0001] The present invention relates to a liquid crystal display device,

The present invention relates to a liquid crystal display, and more particularly, to a liquid crystal display including a liquid crystal layer having a nematic liquid crystal and a ferroelectric liquid crystal.

BACKGROUND ART [0002] Liquid crystal display devices are one of the most widely used flat panel display devices, and studies for high image quality, high brightness, and large size have been actively conducted. As a part of the study, the structure of the electrodes in the liquid crystal display device has been diversified and complicated for the purpose of high image quality, high brightness, and large size of the liquid crystal display device. When a driving voltage is applied to these electrodes, the liquid crystal molecules of the liquid crystal layer are changed in arrangement by an applied electric field, and the liquid crystal molecules are not uniformly arranged by the electrodes and are not stable. Uneven and unstable arrangement of the liquid crystal molecules causes a problem of lowering the luminance of the liquid crystal display device.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a liquid crystal display device having improved brightness.

The problems to be solved by the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

One embodiment according to the concept of the present invention provides a liquid crystal display device. The liquid crystal display device includes a first substrate, a second substrate facing the first substrate, a liquid crystal layer disposed between the first and second substrates, a liquid crystal layer disposed between the first substrate and the liquid crystal layer, A first electrode having a first slit and a second electrode disposed between the liquid crystal layer and the second substrate and having a second slit, wherein the liquid crystal layer is a nematic liquid crystal having negative dielectric anisotropy, Nematic liquid crystals and ferroelectric liquid crystals having positive dielectric anisotropy.

According to an embodiment of the present invention, the first slit may be formed on the first electrode so as not to face the second slit.

According to another embodiment of the present invention, the liquid crystal display may be a patterned vertical alignment (PVA) mode.

According to another embodiment of the present invention, the liquid crystal display further includes a first alignment layer disposed between the first electrode and the liquid crystal layer, and a second alignment layer disposed between the second electrode and the liquid crystal layer can do.

According to another embodiment of the present invention, at least one of the first or second alignment layers may include a reactive mesogen material.

According to another embodiment of the present invention, the liquid crystal layer comprises 70 to 99.9% by weight of the nematic liquid crystal having the negative dielectric anisotropy and 0.1 weight% of the mixture of the nematic liquid crystal and the ferroelectric liquid crystal having the positive dielectric anisotropy % To 30% by weight.

According to another embodiment of the present invention, in the mixture of the nematic liquid crystal and the ferroelectric liquid crystal having positive dielectric anisotropy, the ferroelectric liquid crystal may include 10% by weight to 99% by weight.

According to another embodiment of the present invention, the liquid crystal layer may further include a reactive mesogenic material.

According to another embodiment of the present invention, the liquid crystal layer comprises 0.1 to 30% by weight of a mixture of the nematic liquid crystal and the ferroelectric liquid crystal having positive dielectric anisotropy, 0.01 to 3% by weight of the reactive mesogenic material % And a nematic liquid crystal having an extra negative dielectric anisotropy.

Another embodiment according to the concept of the present invention provides a liquid crystal display device. The liquid crystal display device includes a first substrate, a second substrate facing the first substrate, a liquid crystal layer disposed between the first and second substrates, a liquid crystal layer disposed between the first substrate and the liquid crystal layer, And a second electrode disposed between the liquid crystal layer and the second substrate and having a second slit, wherein the liquid crystal layer includes a non-ferroelectric liquid crystal, a ferroelectric liquid crystal, (ferroelectric liquid crystal).

According to an embodiment of the present invention, the liquid crystal layer may include 0.1 wt% to 30 wt% of the ferroelectric liquid crystal.

According to another embodiment of the present invention, the non-ferroelectric liquid crystal may include a nematic liquid crystal having the negative dielectric anisotropy.

According to another embodiment of the present invention, the liquid crystal layer may include 70 wt% to 99.9 wt% of the nematic liquid crystal having negative dielectric anisotropy and 0.1 wt% to 30 wt% of the ferroelectric liquid crystal.

According to another embodiment of the present invention, the liquid crystal layer may further include a reactive mesogenic material.

According to another embodiment of the present invention, the liquid crystal layer may comprise 0.1 to 30% by weight of the ferroelectric liquid crystal, 0.01 to 3% by weight of the reactive mesogen material and an excess of the negative dielectric anisotropy Nematic liquid crystals.

According to the embodiment of the present invention, the liquid crystal display device may include a nematic liquid crystal having negative dielectric anisotropy, a nematic liquid crystal having positive dielectric anisotropy, and a liquid crystal layer containing ferroelectric liquid crystal molecules. The alignment uniformity and stability of the liquid crystal molecules in the liquid crystal layer can be improved by the ferroelectric liquid crystal molecules of the liquid crystal layer, and the brightness of the liquid crystal display device can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding and assistance of the invention, reference is made to the following description, taken in conjunction with the accompanying drawings, in which:
1 is a plan view for explaining a liquid crystal display according to an embodiment of the present invention.
2 is a cross-sectional view illustrating a liquid crystal display according to an embodiment of the present invention.
3A to 3I are plan views illustrating a structure of a first electrode or a second electrode according to embodiments of the present invention.
4 is a graph showing electrical characteristics of a liquid crystal layer according to an embodiment of the present invention.
FIGS. 5A to 5E are graphs comparing transmittances of the liquid crystal display devices of the first to fourth embodiments with the liquid crystal display devices of the first to third comparative examples.
FIG. 5F is a graph comparing transmittances of the liquid crystal display devices of Examples 3 and 9 with the liquid crystal display device of Comparative Example 3. FIG.
6A to 6D are graphs for comparing the response speeds of the liquid crystal display devices of the first to fourth embodiments and the liquid crystal display devices of the first to third comparative examples.
FIG. 6E is a graph comparing the response speeds of the liquid crystal display devices of Examples 3 and 9 and the liquid crystal display device of Comparative Example 3. FIG.
FIG. 7A is a graph showing the transmittance of the liquid crystal display devices of Examples 5 to 8, and FIG. 7B is a graph illustrating the response speed of the liquid crystal display devices of Examples 5 to 8.
FIGS. 8A to 8C and FIGS. 9A to 9C are textures of the liquid crystal display devices of Comparative Examples 1, 3, and 9. FIG.
Figs. 10A and 10B are graphs showing the gray levels of the textures 7a, 7b, 8a and 8b.
FIGS. 11A and 11B are graphs showing transmittances according to voltages applied to the textures of Comparative Examples 1, 3, and 9. FIG.

In order to fully understand the structure and effects of the present invention, preferred embodiments of the present invention will be described with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. It will be apparent to those skilled in the art that the present invention may be embodied in many other specific forms without departing from the spirit or essential characteristics thereof. Those of ordinary skill in the art will understand that the concepts of the present invention may be practiced in any suitable environment.

The terminology used herein is for the purpose of illustrating embodiments and is not intended to be limiting of the present invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. It is to be understood that the terms 'comprises' and / or 'comprising' as used herein mean that an element, step, operation, and / or apparatus is referred to as being present in the presence of one or more other elements, Or additions.

When a film (or layer) is referred to herein as being on another film (or layer) or substrate it may be formed directly on another film (or layer) or substrate, or a third film Or layer) may be interposed.

Although the terms first, second, third, etc. have been used in various embodiments herein to describe various regions, films (or layers), etc., it is to be understood that these regions, do. These terms are merely used to distinguish any given region or film (or layer) from another region or film (or layer). Thus, the membrane referred to as the first membrane in one embodiment may be referred to as the second membrane in another embodiment. Each embodiment described and exemplified herein also includes its complementary embodiment. Like numbers refer to like elements throughout the specification.

The terms used in the embodiments of the present invention may be construed as commonly known to those skilled in the art unless otherwise defined.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[[Liquid crystal display device]]

1 and 2 are a plan view and a cross-sectional view for explaining a liquid crystal display according to an embodiment of the present invention.

Referring to FIGS. 1 and 2, the liquid crystal display includes a first display panel 100, a second display panel 200 facing the first display panel 100 and a second display panel 200 facing the first and second display panels 100, And a liquid crystal layer 300 disposed between the substrates 100 and 200. The liquid crystal display may further include a first polarizing plate 400 and a second polarizing plate 450 having a transmission axis perpendicular to the transmission axis of the first polarizing plate 400.

The first display panel 100 may include a first substrate 110, a thin film transistor (TFT), and a first electrode 130. The first substrate 110 may include a transparent insulating material such as glass.

The thin film transistor may be disposed on one side of the first substrate 110. The thin film transistor (TFT) includes a gate electrode 112, a gate insulating layer 114, a semiconductor 116, a source electrode 122, and a drain electrode electrode, 124). The gate electrode 112 may include a single layer or a multi-layer metal or metal alloy, and the gate insulating layer 114 may include silicon oxide, silicon nitride, or silicon oxynitride. The intrinsic semiconductor 116 may include amorphous silicon. The source electrode 122 and the drain electrode 124 may be spaced apart from each other on the intrinsic semiconductor 116. A channel of a thin film transistor (TFT) may be formed in the intrinsic semiconductor 116 between the source electrode 122 and the drain electrode 124. The source electrode 122 may be electrically connected to a data line DL and receive a data voltage from the data line DL. The drain electrode 124 may be electrically connected to the first electrode 130.

According to an aspect, the thin film transistor (TFT) may further include resistive contact members 118 and 120 disposed between the intrinsic semiconductor 116 and the source and drain electrodes 122 and 124. The resistive contact members 118 and 120 may include silicide or n ⁺ hydrogenated amorphous silicon doped with an n-type impurity at a high concentration.

A first insulating layer 126 having a contact hole 128 may be formed on the thin film transistor TFT. The first insulating layer 126 may include an inorganic insulating material such as silicon oxide, silicon nitride, silicon oxynitride, or an organic insulating material such as a resin. The contact hole 128 may expose the upper surface of the drain electrode 124.

A first electrode 130 may be formed on the first insulating layer 126. The first electrode 130 may be a pixel electrode. The first electrode 130 may be electrically connected to the drain electrode by a contact hole. The first electrode 130 may receive a data voltage from the drain electrode. The first electrode 130 may include a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO).

According to an embodiment of the present invention, the first electrode 130 may include a domain dividing means, for example, first slits 132a and 132b. The first slits 132a and 132b may have a pattern in which the first electrode 130 is removed. When a voltage is applied to the first electrode 130 and the second electrode 230, the first slits 132a and 132b generate an electric field between the first and second electrodes 130 and 230, The electric field may be formed by the first slits 132a and 132b so that the electric field is not inclined perpendicularly to the surface of the first substrate 110 but inclined at the same time with vertical and horizontal components. In another embodiment of the present invention, the domain dividing means may have a protrusion shape formed on the first electrode 130 and protruding from the first electrode 130 toward the liquid crystal layer 300.

The first electrode 130 may have a variety of structures depending on the structure of the first slits 132a and 132b. The structure of the first slits 132a and 132b of the first electrode 130 will be described in detail below.

According to another embodiment of the present invention, the first display panel 100 may further include a first alignment layer 140 between the first electrode 130 and the liquid crystal layer 300. The first alignment layer 140 may orient liquid crystal molecules in the liquid crystal layer 300 in a pre-tilt direction. According to one embodiment, the first alignment layer 140 may be formed of a material selected from the group consisting of poly-amic acid, polyimide, lecithin, nylon, and PVA (polyvinylalcohol) And the like. According to another embodiment, the first alignment layer 140 may further include a reactive mesogen material.

The first polarizing plate 400 may be disposed on the other surface of the first substrate 110. The other surface of the first substrate 110 may be a surface corresponding to the one surface.

The second display panel 200 may include a second substrate 210 and a second electrode 230. The second substrate 210 may include a transparent insulating material such as glass.

The second electrode 230 may be disposed on one side of the second substrate 210 and one side of the second substrate 210 may face the first display panel 100. The second electrode 230 may be a common electrode. The second electrode 230 may include a transparent conductive material such as ITO or IZO.

According to an embodiment of the present invention, the second electrode 230 may include a domain dividing means, for example, a second slit 232a or 232b. The second slits 232a and 232b may have a pattern in which the second electrode 230 is removed and the second electrode 230 has a pattern. When a voltage is applied to the first electrode 130 and the second electrode 230, the second slits 232a and 232b generate an electric field between the first and second electrodes 130 and 230, By the second slits 232a and 232b, the electric field may be inclined at the same time with vertical and horizontal components, not perpendicular to the surface of the second substrate 210. According to another embodiment of the present invention, the second electrode 230 may have a protrusion shape protruding from the second electrode 230 toward the liquid crystal layer 300.

The second electrode 230 may have a variety of structures depending on the structure of the second slits 232a and 232b. The structure of the second slits 232a and 232b of the second electrode 230 will be described in detail below.

According to embodiments of the present invention, the liquid crystal display device may be a liquid crystal display device of a patterned vertical alignment (PVA) mode. The first electrode 130 having the first slits 132a and 132b and the second electrode 230 having the second slits 232a and 232b are opposed to each other. The first slits 132a and 132b, And the second slits 232a and 232b do not face each other. For example, the first electrode 130 having the first slits 132a and 132b and the second electrode 230 having the second slits 232a and 232b may have substantially the same structure, The first and second electrodes 130 and 230 may be disposed so that the slits 132a and 132b do not face the second slits 232a and 232b. Alternatively, the first and second electrodes 130 and 230 may have different structures, and the first slits 132a and 132b of the first electrode 130 and the first slits 132a and 132b of the second electrode 230 may have different structures. The two slits 232a and 232b may not face each other. In addition, the first slits 132a and 132b and the second slits 232a and 232b may be substantially not overlapped with each other when viewed in plan. The first slits 132a and 132b and the second slits 232a and 232b may be alternated when viewed in a plan view.

According to the embodiments of the present invention, as described above, the voltage is applied by the first slits 132a and 132b and the second slits 232a and 232b of the first and second electrodes 130 and 230 An oblique electric field may be formed between the first and second electrodes 130 and 230. Accordingly, multi-domains (D1 to D4) can be formed within one pixel. Referring to FIG. 1, in this embodiment, liquid crystal molecules are arranged in four directions, so that four domains (D1 to D4) can be formed in one pixel. However, in the present invention, the number of domains formed in a pixel is not limited.

According to one embodiment, the second display panel 200 may further include a color filter 212. The color filter 212 may be disposed between the second substrate 210 and the second electrode 230. A light shielding member 214 may be disposed on one side of the second substrate 210 and the color filter 212 may be formed in each region defined by the light shielding member 214. The color filter 212 may be protected by a second insulating layer 216. In the present embodiment, the color filter 212 is disposed on the second display panel 200, but the color filter 212 may be disposed on the first display panel 100. The position of the color filter 212 is not limited in the present invention.

According to another embodiment of the present invention, the second display panel 200 may further include a second alignment layer 240 between the second electrode 230 and the liquid crystal layer 300. The second alignment layer 240 may initially align the liquid crystal molecules in the liquid crystal layer 300 in one direction. According to one embodiment, the second alignment layer 240 may be formed of a material selected from the group consisting of poly-amic acid, polyimide, lecithin, nylon, and PVA (polyvinylalcohol) And the like. According to another embodiment, the second alignment layer 240 may further include a reactive mesogen material.

The second polarizer 450 may be disposed on the other surface of the second substrate 210. The other surface of the second substrate 210 may be a surface corresponding to the one surface. The second polarizing plate 450 may transmit a linearly polarized light component oscillating in a direction perpendicular to the light passing through the first polarizing plate 400.

The liquid crystal layer 300 may fill the spaces between the first and second display panels 100 and 200. According to one embodiment, the liquid crystal layer 300 may include a negative nematic liquid crystal having a negative dielectric anisotropy, a positive nematic liquid crystal and a ferroelectric liquid crystal having positive dielectric anisotropy, crystal. According to another embodiment, the liquid crystal layer 300 may include a non-ferroelectric liquid crystal and a ferroelectric liquid crystal. The liquid crystal layer 300 will be described in detail below.

According to an exemplary embodiment of the present invention, the liquid crystal display may further include an optical compensation film 430. The optical compensation film 430 may be disposed between the second polarizer 450 and the second substrate 210. When the liquid crystal molecules are maintained in a vertically aligned state, the polarization axes of the first polarizing plate 400 and the second polarizing plate 450 are orthogonal to each other and no light leakage occurs when viewed from the front, The polarization angle formed by the polarization axes of the light sources 400 and 450 becomes large, and light leakage can be generated. An optical compensation film 430 such as a biaxial film or a uniaxial film may be disposed to compensate for the light leakage.

As described above, since the liquid crystal layer 300 of the liquid crystal display device of the PVA mode includes the ferroelectric liquid crystal, the alignment of the liquid crystal composition can be made uniform along with the nematic liquid crystal, and the stability of alignment can be improved. Accordingly, the brightness of the liquid crystal display device including the liquid crystal layer 300 can be improved. Further, by including a reactive mesogen material in at least one of the first and second alignment layers 140 and 240, the alignment speed of the liquid crystal molecules in the liquid crystal layer 300 is increased, and the angle of orientation is increased, Can be improved.

Hereinafter, the structure of the first and second electrodes 130 and 230 will be described in detail.

[First and Second Electrode Structures]

The electrode structure described below represents the first electrode 130 as an example, but the second electrode 230 may have one of the following electrode structures. As described above, if the first slits 132a and 132b do not face the second slits 232a and 232b, the structures of the first and second electrodes may be the same or different. It is possible.

3A to 3I are plan views for explaining the structure of the first and second electrodes 130 and 230 according to the embodiments of the present invention.

Referring to FIG. 3A, the first electrode 130 may have a Chevron pattern. The first slits 132a and 132b of the first electrode 130 are formed in a V shape and have a first line 132a extending in a first direction D1 and a second line 132b extending in a second direction And a second line 132b extending in the direction D2 may be connected.

Referring to FIG. 3B, the first electrode 130 may have a modified Chevron pattern. The structure of the first slits 132a and 132b is similar to the structure shown in FIG. 3A, except that the middle of the first line 132a is cut by the first electrode 130, May be cut off by the first electrode 130.

Referring to FIG. 3C, the first electrode 130 may have an X-shaped pattern. The structure of the first slits 132a and 132b includes a first line 132a extending in the first direction D1 and a second line 132b extending in the second direction D2 intersecting the first direction D1. ). Unlike FIG. 3A, the first and second lines 132a and 132b are not connected to each other.

Referring to FIG. 3D, the first electrode 130 may have a stripe pattern. The structure of the first slit 132 may be such that lines extending in one direction are repeatedly provided in parallel with each other.

Referring to FIG. 3E, the first electrode 130 may have a lattice pattern. The structure of the first slits 132a and 132b includes a first line 132a extending in a first direction D1 and a second line 132b extending in a second direction D2 perpendicular to the first direction D1. 132b may be connected.

Referring to FIG. 3F, the first electrode 130 has rectangular patterns, and each of the rectangular patterns may include four triangles divided by diagonal lines of the square pattern. The structure of the first slits 132a, 132b, 132c may be a structure that divides the rectangular pattern and divides the four triangles in the rectangular patterns. More specifically, the first slits 132a, 132b and 132c include a first line 132a extending in a first direction D1, a second line 132b extending in a second direction D2 different from the first direction D1, 132b and a third line 132c that extends in a third direction D3 that intersects the second direction D2 so that the first and second lines 132a, And the first and third lines 132a and 132c may be connected to each other.

Referring to FIG. 3G, the first electrode 130 has rectangular patterns, and each of the rectangular patterns may include two triangles divided by a diagonal line of the rectangular pattern. The structure of the first slits 132a and 132b may be a structure that divides the rectangular pattern and divides the two triangles in the rectangular patterns. More specifically, the first slit includes a first line 132a extending in a first direction D1 and a second line 132b extending in a second direction D2 different from the first direction D1 can do. The first and second lines 132a and 132b may be connected to each other.

Referring to FIG. 3H, the first electrode 130 has rectangular patterns, and may include a circular first slit 132a in the rectangular pattern. In FIG. 3h, the first slit 132a in the rectangular pattern is circular, but the first slit 132a may be polygonal. In addition, the first slit may further include a structure 132b for dividing the rectangular patterns.

Referring to FIG. 3I, the first electrode 130 may include a plurality of circular first slits 132. The first slits 132 may be spaced apart from each other at regular intervals to align rows and columns. In FIG. 3I, the first slits 132 are shown in a circular shape, but the first slits 132 may be polygonal.

Hereinafter, the liquid crystal layer will be described in detail.

[ Liquid crystal layer _ 1st Example ]

The liquid crystal layer may include a negative nematic liquid crystal having negative dielectric anisotropy, a positive nematic liquid crystal having positive dielectric anisotropy, and a ferroelectric liquid crystal.

According to one embodiment, the liquid crystal layer may comprise a nematic liquid crystal having a negative dielectric anisotropy of about 70 wt% to about 99.9 wt%. The liquid crystal layer may further comprise a mixture of nematic liquid crystal and ferroelectric liquid crystal having a dielectric anisotropy in an amount of about 0.1 wt% to about 30 wt%.

Wherein the mixture of nematic liquid crystal and ferroelectric liquid crystal having positive anisotropy comprises a nematic liquid crystal having a dielectric anisotropy in an amount of about 1 wt% to 90 wt% and a ferroelectric liquid crystal in an amount of about 10 wt% to about 99 wt% can do.

According to one embodiment, the ferroelectric liquid crystal in the liquid crystal layer may be in the range of about 0.01 wt% to about 29.7 wt%. When the ferroelectric liquid crystal is about 0.01% by weight or less of the total amount of the liquid crystal layer, the liquid crystal aligning property of the liquid crystal layer may be unstable. Further, when the ferroelectric liquid crystal exceeds about 29.7% by weight of the total amount of the liquid crystal layer, the viscosity of the liquid crystal layer increases and the response time of the display device including the liquid crystal layer may be slowed down. Preferably, the ferroelectric liquid crystal may be about 10% by weight of the total amount of the liquid crystal layer.

In the following, exemplary materials of the nematic liquid crystal having negative dielectric anisotropy, nematic liquid crystal having positive dielectric anisotropy and ferroelectric liquid crystal will be described. With the exemplary materials described below, the nematic liquid crystal having the negative dielectric anisotropy of the present invention, the nematic liquid crystal having positive dielectric anisotropy, and the ferroelectric liquid crystal are not limited thereto.

First, the characteristics of a nematic liquid crystal are briefly described, and examples of a nematic liquid crystal having a negative dielectric anisotropy and a nematic liquid crystal having a positive dielectric anisotropy are categorized.

Nematic liquid crystals are liquid crystals in which liquid crystal molecules are irregular in position but their long axes are all directed in a certain direction. Since each molecule of the nematic liquid crystal can freely move in the major axis direction, it is easy to flow due to a small viscosity, and the direction of the nematic molecule is substantially equal to the up and down directions, so that polarization is canceled and generally does not exhibit ferroelectricity. In the direction perpendicular to the axial direction of molecules of the liquid crystal, physical properties are very different. Therefore, a nematic liquid crystal is a material having optical anisotropy. A nematic liquid crystal having a negative dielectric anisotropy when the difference in permittivity parallel to the axial direction and a dielectric constant (DELTA epsilon) perpendicular to the axial direction is smaller than 0 is referred to as a nematic liquid crystal having positive dielectric anisotropy, .

Negative oilfield Anisotropy  Have Nematic  Liquid crystal

According to one embodiment, the nematic liquid crystal having negative dielectric anisotropy may include nematic liquid crystal molecules having negative dielectric anisotropy. In one aspect, the nematic liquid crystal molecules having negative dielectric anisotropy may be single. In another aspect, the nematic liquid crystal molecules having negative dielectric anisotropy may be different from each other. For example, the nematic liquid crystal molecules having negative dielectric anisotropy may include liquid crystal molecules having negative dielectric anisotropy having a first dielectric constant and liquid crystal molecules having negative dielectric anisotropy having a second dielectric constant. At this time, the second dielectric constant may be different from the first dielectric constant.

According to another embodiment, the nematic liquid crystal having negative dielectric anisotropy may include nematic liquid crystal molecules having negative dielectric anisotropy and first base liquid crystal molecules. Each of the first base liquid crystal molecules may include at least one selected from the group consisting of liquid crystal molecules having negative dielectric anisotropy and liquid crystal molecules having positive dielectric anisotropy and neutral liquid crystal molecules. In one aspect, the nematic liquid crystal having negative dielectric anisotropy may include nematic liquid crystal molecules having one kind of negative dielectric anisotropy and first base molecules. In another aspect, the nematic liquid crystal having negative dielectric anisotropy may include liquid crystal molecules having various kinds of negative dielectric anisotropy and first base liquid crystal molecules.

Hereinafter, nematic liquid crystals having negative dielectric anisotropy will be described by way of examples. The following materials may be used alone or in combination.

The nematic liquid crystal having negative dielectric anisotropy may include a halogen group, a cyanide group, or an isocyanate group nematic liquid crystal. The nematic liquid crystal having negative dielectric anisotropy may be used alone or in combination with a halogen group, a cyanide group, or an isocyanate group nematic liquid crystal. The nematic liquid crystal having negative dielectric anisotropy may further include first base liquid crystal molecules.

The nematic liquid crystal having the dielectric anisotropy of a halogen-based negative may include a fluorine group, a chlorine group or a bromine group material, and may have a single or multiple ring structure.

Nematic liquid crystals having a negative dielectric anisotropy of a halogen-based bicyclic structure can be represented by the following general formulas (1) and (2).

Formula 1

(2)

In Formulas 1 and 2, R is alkyl having 1 to 15 carbon atoms, or alkoxy, wherein hydrogen may be replaced by CN, CF ₃ , or halogen, CH ₂ - group may be substituted with -CH═CH-, -O-, -CO-, -COO-, -OOC-, -O-OC-O- or -S-), X is independently of each other Halogenated alkyl, halogenated alkoxy, halogenated alkenyl or halogenated oxy having from 1 to 15 carbon atoms, and L ¹ and L ² Are independently of each other hydrogen or halogen.

Nematic liquid crystals having a negative dielectric anisotropy of a halogen-based tricyclic structure can be represented by the following formulas (3) to (6).

(3)

Formula 4

Formula 5

6

In the formulas (3) to (6), R, L ¹ and L ² are as defined in the above formulas (1) and (2), L ³ and L ⁴ independently of one another are hydrogen or halogen, Z is a single bond, -CF _{2 O-, -OCF 2 -, -COO-} , -O-CO-, -CH 2 CH 2 -, -CH = CH-, -C = C-, -CH 2 O-, - (CH 2) 4 -, CF = CF-, -CH = CF- or -CF = CH-.

Nematic liquid crystals having a negative dielectric anisotropy of a halogen-based tetra-cyclic structure can be represented by the following formulas (7) to (9).

Formula 7

8

Formula 9

In formulas (7) to (9), Y represents hydrogen or halogen, R ¹ represents alkyl having 1 to 15 carbon atoms, or alkenyl, R ² represents 1 to 15 carbon (In R ¹ and R ² , hydrogen may be replaced by CN, CF ₃ , or a halogen atom), or an alkyl, alkenyl, or alkoxy group having an atom , CH ₂ Group may be substituted by -O-, -S-, -C═C-, -CH═CH-, -OC-O- or -O-CO-), Z represents a single bond, -CF ₂ O- _{, -OCF 2 -, -COO-, -O} -CO-, -CH 2 CH 2 -, -CH = CH-, -C = C-, -CH 2 O-, - (CH 2) 4 -, CF = CF-, -CH = CF- or -CF = CH-.

The nematic liquid crystal having a dielectric negative dielectric anisotropy has a side fluorinated indane derivative and can be represented by the following chemical formula (10).

10

In the above formula, m represents an integer, and n is 0 or 1.

Nematic liquid crystals having a dielectric anisotropy of negative cyanogen can be represented by the following formulas (11) to (13).

Formula 11

Formula 12

Formula 13

In Formulas 11 to 13, R ³ is an alkyl group having 1 to 15 carbon atoms, wherein hydrogen may be unsubstituted or at least monosubstituted by CN, CF _{3 ,} or halogen, and CH ₂ Group may be replaced by -O-, -S-, -C = C-, -CH = CH-, -OC-O- or -O-CO-), L ¹ and L ² independently of one another are hydrogen Or halogen and Z is a single bond, -CF ₂ O-, -OCF ₂ -, -COO-, -O-CO-, -CH ₂ CH ₂ -, -CH = CH-, -C = C -, -CH ₂ O-, - (CH ₂ ) ₄ -, CF = CF-, -CH = CF- or -CF = CH-.

The nematic liquid crystal having negative dielectric anisotropy may be a single substance or a mixture. According to the embodiment, the nematic liquid crystal mixture having a negative dielectric anisotropy,

(a) a liquid crystal component comprising at least one compound having a dielectric anisotropy of less than -1.5 A:

(b) a liquid crystal component B consisting of at least one compound having dielectric anisotropy of -1.5 to +1.5; and

(c) a chiral component C.

The liquid crystal component A may include at least one compound represented by the following general formulas (14) to (17).

Formula 14

Formula 15

Formula 16

Formula 17

The liquid crystal component B may include one or more compounds represented by the following general formulas (18) to (20). The liquid crystal component B may be the first base liquid crystal molecules described above.

18

Formula 19

20

In formulas 14 to 20, R < ⁴ > And R ⁵ are each independently selected from the group consisting of alkyl, alkoxy, alkoxy alkyl, alkenyl or alkenyl oxy having 1 to 15 carbon atoms (wherein hydrogen May be substituted by CN, CF ₃ , or a halogen atom, and the -CH ₂ - group may be replaced by -CH═CH-, -O-, -CO-, -COO-, -OOC-, -O- OC-O- or -S-), Y ¹ represents hydrogen or halogen.

Chiral component C is available with a number of chiral dopants such as the following examples. The choice of dopant is not important in itself.

Positive heredity Anisotropy  Have Nematic  Liquid crystal

According to one embodiment, the nematic liquid crystal having positive dielectric anisotropy may comprise nematic liquid crystal molecules having positive dielectric anisotropy. In one aspect, the nematic liquid crystal molecules having positive dielectric anisotropy may be single. In another aspect, the nematic liquid crystal molecules having positive dielectric anisotropy may be different from each other. For example, the nematic liquid crystal molecules having positive dielectric anisotropy may include liquid crystal molecules having a positive dielectric anisotropy having a first dielectric constant and liquid crystal molecules having positive dielectric anisotropy having a second dielectric constant. At this time, the second dielectric constant may be different from the first dielectric constant.

According to another embodiment, the nematic liquid crystal having positive dielectric anisotropy may comprise nematic liquid crystal molecules having positive dielectric anisotropy and second base liquid crystal molecules. Each of the second basis liquid crystal molecules may include at least one selected from the group consisting of liquid crystal molecules having negative dielectric anisotropy and liquid crystal molecules having positive dielectric anisotropy and neutral liquid crystal molecules. In one aspect, the nematic liquid crystal having positive dielectric anisotropy may include nematic liquid crystal molecules having one kind of positive dielectric anisotropy, and second base molecules. In another aspect, the nematic liquid crystal having positive dielectric anisotropy may include liquid crystal molecules having various kinds of amounts of dielectric anisotropy and second base liquid crystal molecules.

Hereinafter, nematic liquid crystals having positive dielectric anisotropy will be described by way of examples. The following materials may be used alone or in combination.

The nematic liquid crystal having positive dielectric anisotropy may include a nematic liquid crystal having a cyanide group, an isocyanate group, and a halogen group in an amount of dielectric anisotropy. The nematic liquid crystal having positive dielectric anisotropy can be used alone or in combination with a nematic liquid crystal having a cyanide group, an isocyanate group and a halogen group anisotropy. In addition, the nematic liquid crystal having positive dielectric anisotropy may further include second base liquid crystal molecules.

The nematic liquid crystal having the positive dielectric anisotropy of the cyanide system may have a bicyclic structure or a tricyclic structure.

The bimetallic nematic liquid crystal of bicyclic structure can be represented by the formula (21).

Formula 21

In formula (21), R ⁶ is an alkenyl having 1 to 15 carbon atoms, wherein hydrogen may be replaced by CN, CF ₃ , or halogen, and the -CH ₂ - group is -CH = Specific examples of the formula (21) are shown below. ≪ Desc / Clms Page number 13 >

In formula (21), R ⁷ is H, CH ₃ , C ₂ H ₅ or nC ₃ H ₇ .

A nematic liquid crystal having a positive dielectric anisotropy of a three-ring structure can be represented by the formula (22).

Formula 22

R ³ is as R ³ is unsubstituted or substituted with CN, CF _3, or halogen-alkyl (alkyl) having at least one carbon atom less than the 15-substituted one by (halogen) groups as defined in Formula 11 to 13, wherein Of these alkyls, one or more CH ₂ groups may be replaced by -O-, -S-, -C═C-, -CH═CH-, -OC -O- or -O-CO-, and L ¹ and L ² are each independently hydrogen or halogen.

A nematic liquid crystal having an isocyanate-based positive dielectric anisotropy can be represented by the following formula (23).

Formula 23

또는

이며, B는 -CH₂-CH₂- 또는 -C=C- 이며, X¹는 수소 또는 할로겐(halogen)이며, m은 1 2, 3, 또는 4이다. 화학식 23의 구체적인 예들이 다음에 도시된다.In formula (23), R ⁸ is C _n H _{2n +1} O, C _n H _{2n +1} , or C _n H2 _{n -1} , wherein n is 1 to 15, and A is

or

B is -CH ₂ -CH ₂ - or -C = C-, X ¹ is hydrogen or halogen, and m is 1, 2, 3, or 4. Specific examples of formula (23) are shown below.

The nematic liquid crystal having a halogen-based positive dielectric anisotropy may include a fluorine-based or chlorine-based material, and may have a single or multi-ring structure. Nematic liquid crystals having a fluorine-based positive dielectric anisotropy can be represented by the following formulas (24) to (27).

24

25

26

27

In Formulas 24 to 27, R ⁹ and R ¹⁰ are independently selected from the group consisting of alkyl having 1 to 15 carbon atoms, alkoxy, fluorinated alkyl, fluorinated alkoxy, alkenyl Alkenyloxy, alkoxyalkyl or fluorinated alkenyl; L ²¹ , L ²² , L ²³ and L ²⁴ are each independently hydrogen or fluorine; , Z is a single bond, -CF ₂ O-, -OCF ₂ -, -COO-, -O-CO-, -CH ₂ CH ₂ -, -CH═CH-, -C═C-, -CH ₂ O -, - (CH ₂ ) ₄ -, CF = CF-, -CH = CF- or -CF = CH-.

A nematic liquid crystal having a positive dielectric anisotropy of a halogen-based bicyclic structure can be represented by the following formula (28).

28

In formula (28), R ¹¹ represents hydrogen, halogen, alkenyl having 1 to 15 carbon atoms, alkenyloxy, alkynyl or alkynoxy, and R ¹¹ , at least one -CH ₂ - group may be replaced by -O-, C═O or -S-, L ⁵ is halogen, a fluorinated alkyl of 1 to 15 carbon atoms, a fluorinated alkoxy, Fluorinated alkenyl, alkenyloxy or oxyalkyl, -OCF ₃ , -OCHFCF ₃ or SF ₅ , and L ⁶ , L ⁷ , L ⁸ and L ⁹ are independently of each other (H) or halogen and Z is a single bond, -CF ₂ O-, -OCF ₂ -, -COO-, -O-CO-, -CH ₂ CH ₂ -, -CH = CH- , -C = C-, -CH ₂ O-, - (CH ₂ ) ₄ -, CF = CF-, -CH = CF- or -CF = CH-. Specific examples of formula (28) are shown below.

In the above formula, n is 1 to 15.

Nematic liquid crystals having a positive dielectric anisotropy of a halogen-based tricyclic structure can be represented by the following formulas (29) to (33).

Formula 29

Formula 30

31

(32)

Formula 33

In formulas 29 to 33, R ¹² is alkyl or alkenyl having 1 to 15 carbon atoms, wherein the alkyl or alkenyl is unsubstituted or at least monosubstituted by CN, CF ₃ , And one or more -CH ₂ - groups may be replaced by -O-), X ³ is -F, -Cl, -OCF ₃ , -OCHF ₂ , -OCH ₂ F or -CF ₃ . Specific examples of the formula (29) are as follows.

Wherein R < ¹² > is as defined above.

A nematic liquid crystal having a positive dielectric anisotropy of a halogen-based four-ring structure can be represented by the following formulas (34) to (36).

(34)

(35)

Formula 36

In the formulas (34) to (36), R ¹³ is alkyl, alkoxy or alkenyl having 1 to 15 carbon atoms, wherein hydrogen in the alkyl, alkoxy or alkenyl is CN, CF ₃ or halogen halogen, and the -CH ₂ - group may be substituted with -CH═CH-, -O-, -CO-, -COO-, -OOC-, -O-OC-O- or -S- Z is a single bond, -CF ₂ O-, -OCF ₂ -, -COO-, -O-CO-, -CH ₂ CH ₂ -, -CH═CH-, -C═C-, CH ₂ O-, - (CH ₂ ) ₄ -, CF = CF-, -CH = CF- or -CF = CH-.

A nematic liquid crystal having a positive dielectric anisotropy including a trisubstituted fluorine or a cyanation group can be represented by the formula (37).

37

In Formula 37, at least one of the two R ¹⁴ and R ¹⁵ is an alkenyl group having 15 or fewer carbon atoms, which is unsubstituted or at least monosubstituted by CN, CF ₃ or a halogen, One may be unsubstituted or an alkyl group having up to 15 carbon atoms which is at least monosubstituted by CN, CF ₃ or halogen, wherein one or more of these groups CH ₂ The group may be replaced by -O-, -S-, -C = C-, -OCO-, or -O-CO-. Specific examples of formula (37) are shown below.

n and m are from 1 to 10, preferably from 1 to 5, o and p are each independently the same or different and from 0 to 10, preferably from 0 to 5, with the proviso that the sum o + Is 7 or less.

The nematic liquid crystal having positive dielectric anisotropy may be a single substance or a mixture. A nematic liquid crystal mixture having positive dielectric anisotropy according to one embodiment,

a) a liquid crystal component A consisting of at least one compound having a dielectric anisotropy greater than +1.5,

b) a liquid crystal component consisting of at least one compound having a dielectric anisotropy of -1.5 to +1.5, and

c) optionally comprising an optically active component C,

The liquid crystal component A may comprise one or more compounds of the above formula (37). The liquid crystal component B may include at least one compound represented by the following formula (38). The liquid crystal component B may be the second base liquid crystal molecules described above.

Component C is cholesteryl nonanoate (CN), S-811, S-1011, S-2011 (Merck KGaA from Darmstadt, Germany) and CB15 Of BDH) are available. The choice of dopant is not important in itself.

Formula 38

R ¹⁶ and R ¹⁷ is an alkyl group (alkyl), respectively and independently from each other the same or different, each is unsubstituted or substituted with CN, CF _3, or at least one substituted carbon atom of 15 or less with a halogen (halogen), Wherein one or more CH ₂ of these alkyl groups may be replaced by -O-, -S-, -C = C-, -CH = CH-, -OC-O- or -OCO-, The phenylene (1, 4-phenylene) ring may be monosubstituted or monosubstituted independently of each other by fluorine.

Ferroelectric liquid crystal

Ferroelectric liquid crystal is a kind of dielectric which is spontaneous polarization without electric field and is electrically insulated. However, unlike general dielectric, dielectric polarization is not proportional to the electric field, and the relationship between polarization and electric field And exhibits an ideality with an electric history. Ferroelectric liquid crystals not only have characteristic spontaneous polarization but also have a property that the spontaneous polarization is reversed by an electric field (polarization reversal).

According to one embodiment, the ferroelectric liquid crystal may include ferroelectric liquid crystal molecules. In one aspect, the ferroelectric liquid crystal molecules may be single. In another aspect, the ferroelectric liquid crystal molecules may be different from each other. For example, the ferroelectric liquid crystal molecules may include a first ferroelectric liquid crystal molecule and a second ferroelectric liquid crystal molecule. At this time, the second ferroelectric liquid crystal molecules may be different from the first ferroelectric liquid crystal molecules.

According to another embodiment, the ferroelectric liquid crystal may include ferroelectric liquid crystal molecules and third base liquid crystal molecules. Each of the third base liquid crystal molecules may include at least one selected from the group consisting of liquid crystal molecules having negative dielectric anisotropy and liquid crystal molecules having positive dielectric anisotropy and neutral liquid crystal molecules. In one aspect, the ferroelectric liquid crystal may include one kind of ferroelectric liquid crystal molecules and third base molecules. In another aspect, the ferroelectric liquid crystal may include ferroelectric liquid crystal molecules different from each other and third base molecules.

Hereinafter, ferroelectric liquid crystals will be described by giving examples. The following materials may be used alone or in combination.

The ferroelectric liquid crystal may be chiral. For example, the ferroelectric liquid crystal may be a fluorine chiral end ferroelectric liquid crystal, a chiral allyl ester ferroelectric liquid crystal, a center core polyring chiral ferroelectric liquid crystal, or a smectic chiral liquid crystal smetic chiral ferroelectric liquid crystal and the like. The ferroelectric liquid crystal may also be a banana-shaped ferroelectric liquid crystal. The ferroelectric liquid crystal may include a fluorine chiral end ferroelectric liquid crystal, a chiral allyl ester ferroelectric liquid crystal, a center core polyring chiral ferroelectric liquid crystal, a smectic chiral ferroelectric liquid crystal, Liquid crystal and banana shape ferroelectric liquid crystal may be used alone or in combination. In addition, the ferroelectric liquid crystal may further include third base liquid crystal molecules.

The fluorine-based chiral terminal ferroelectric liquid crystal may be represented by the following formula (39).

39

Wherein X ⁴ , X ⁵ , X ⁶ and X ⁷ are each independently CF ₃ , CF ₂ H _, CFH ₂ , halogen, alkyl or alkoxy, C and D are independently E is independently selected from the group consisting of a single bond, COO, OOC, and C = C (O), phenyl, mono-fluorophenyl, difluorophenyl, or cyclo- At least one of E is a single bond, q is 0 or 1, and R ¹⁸ is a terminal group of the following formula (40).

40

Wherein Z is O, (CH ₂ ) ₁ O, or (CH ₂ ) ₂ O, J and M are independently selected from hydrogen, alkyl of 1 to 15 carbon atoms, W is a carbon atom from 1 to 15 linear or branched alkyl chain, J, M, W are each different, R ¹⁹ is alkenyl group comprising from 1 to 15 carbon atoms, (alkenyl), alkenyloxy (alkenyloxy), alkynyl (alkynyl ), Or alkynoxy.

The chiral aryl ester liquid crystal may be represented by the formula (41).

Formula 41

In formula (41), R _a and R _b are each independently alkyl having 1 to 20 carbon atoms, Q is -C (= O) O- or -OC (= O) -, Z is fluorine ) Or an alkyl group substituted with a halogen, and * represents optically active carbon. Specific examples of Formula 41 include 4'-n-octyloxyphenyl 4 '- (1,1,1-trifluoro-2-octyloxycarbonyl) biphenyl-4- carboxylate octyloxyphenyl 4 '- (1,1,1-trifluoro-2-octyloxycarbonyl) biphenyl-4-carboxylate.

The core core polyring chiral ferroelectric liquid crystal may be represented by the following formulas (42) to (44).

Formula 42

(42) was synthesized in the same manner as in S-4- (trans-4-heptylcyclohexyl) -3'-chloro-4 "- (1-methylheptyloxy) chloro-4 "- (1-methylheptyloxy) terphenyl).

Formula 43

R-4-octyl-3 " -chloro-4 "-( 1-methylhexyloxy) -3 "-( 4-methylhexyloxy) ) quarterphenyl.

44

S-4-nonyl-3'-fluoro-4 '' - (2-chloropropyloxy) quaterphenyl (S-4-nonyl-3'-fluoro-4 ' ) quarterphenyl.

Formula 45

The compound of formula 45 is prepared by reacting butyl S-2- (4-octyl-2'-fluoro-3 "-trifluoromethyl-4 '2'-fluoro-3"-trifluoromethyl-4'''- quarterphenyloxy) -propionate).

The ferroelectric smectic liquid crystal may be represented by at least one of the following formulas (47) and (48).

Formula 47

48

In formulas (47) and (48), R ²⁰ and R ²¹ are each a linear alkyl group of 1 to 9 carbon atoms, and R ²² And R ²³ is in each identical or different C 1 -C 18 linear alkyl (alkyl), and (R ²⁰ to R ^23, hydrogen can be optionally substituted with CN, CF _3, or halogen (halogen) atom, -CH ₂ -Group may optionally be substituted by -CH = CH-, -O-, -CO-, -COO-, -OOC-, -O-OC-O- or -S-, X is hydrogen or halogen (halogen). Specific examples of the above formulas (47) and (48) are shown below.

The chiral smectic ferroelectric liquid crystal can be represented by the above formula (49).

Formula 49

In formula (49), R ²⁴ represents a chiral or achiral C 1 -C 20 alkyl or alkenyl, R ²⁵ represents a chiral or non-chiral C 1 -C 20 alkoxy Alkenyloxy, alkylcarbonyloxy, alkenylcarbonyloxy, alkenyl-COO-) (in R ²⁴ and R ²⁵ , hydrogen is CN, CF ₃ , or a halogen atom, and the -CH ₂ - group may be substituted with -CH═CH-, -O-, -CO-, -COO-, -OOC-, -O-OC- Or -S-, Z ¹ is a single bond, -COO- or -OOC-, -CH ₂ CH ₂ -, -CH = CH-, -C = C-, -OCH ₂ - or -CH ₂ O-, L ¹⁰ to L ¹⁴ are hydrogen, halogen, cyano, nitro, alkyl having 1 to 20 carbon atoms or alkenyl, (-CH ₂ - group may be substituted by -CH═CH-, -O-, -CO-, -COO-, -OOC-, -O-OC-O- or -S-), X ⁹ Is -CH- or nitrogen. A specific example of the above formula (49) is shown below.

The banana ferroelectric liquid crystal may be represented by the following general formula (50).

50

또는

이고, B1는

또는

이며, R²⁶ 및 R²⁷은 각각 독립적으로 수소 또는 할로겐(halogen)이며, R²⁸ 및 R²⁹는 독립적으로 탄소원자 8개 내지 16개의 알킬(alkyl) 또는 알콕시(alkoxy)이다. 상기 화학식 50의 구체적인 예들이 다음에 도시된다.In formula (50), A < ¹ >

or

, B1 is

or

, R ²⁶ and R ²⁷ are each independently hydrogen or halogen, and R ²⁸ and R ²⁹ are independently alkyl or alkoxy having 8 to 16 carbon atoms. Specific examples of the above formula (50) are shown below.

The ferroelectric liquid crystal may be a ferroelectric liquid crystal single substance or a mixture containing a ferroelectric liquid crystal.

Formula 51

In Formula 51, X ¹⁰ is hydrogen (H), R ³⁰ is hydrogen or alkyl having 1 to 15 carbon atoms, R ³¹ is hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms, Alkenyl group wherein one or two -CH ₂ - groups can in each case be replaced by -O-, -C (= O) O- or -Si (CH ₃ ) ₂ - , At least one hydrogen of the alkyl or alkenyl group may be replaced by fluorine or CH ₃ ), and R ³² , R ³³ , R ³⁴ , and R ³⁵ are each CH ₃ .

As described above, in the liquid crystal layer according to the embodiment of the present invention, when an electric field is applied from the outside, the induced dipole is parallel to the electric field and the nematic liquid crystal having negative dielectric anisotropy is arranged in a direction perpendicular to the electric field . Since the ferroelectric liquid crystal of the liquid crystal layer has a large alignment property with respect to the molecules and an arrangement characteristic according to the electric field, the orientation of the liquid crystal layer can be uniform and stabilized.

According to an embodiment of the present invention, the liquid crystal layer may further include a reactive mesogenic material. Wherein the liquid crystal layer comprises a nematic liquid crystal having from about 0.01 wt% to about 3 wt% of a reactive mesogenic material and a negative dielectric anisotropy of from about 70 wt% to about 99.9 wt% To about 30% by weight of a nematic liquid crystal and a ferroelectric liquid crystal having a dielectric anisotropy, and a nematic liquid crystal having an extra negative dielectric anisotropy.

The reactive mesogenic material means a polymerizable mesogenic compound. A " mesogenic compound " or " mesogenic material " may include one or more rod-shaped, plate-like or disk-shaped mesogenic groups, i.e., materials or compounds containing groups with the ability to induce liquid crystalline phase behavior. The reactive mesogen material may be a material that is polymerized by light such as ultraviolet light and is oriented in accordance with the orientation state of the adjacent material.

An example of such a reactive mesogenic material is a compound represented by the following formula:

P1-A1- (Z1-A2) n-P2,

Here, P1 and P2 are at least one of acrylate, methacrylate, vinyl, vinyloxy and epoxy groups, and A1 and A2 are 1,4-phenylene phenylen and naphthalene-2,6-diyl, Z1 is one of COO-, OCO-, and a single bond, and n can be one of 0, 1, and 2.

More specifically, there can be mentioned a compound represented by one of the following formulas:

Here, P1 and P2 may include at least one of acrylate, methacrylate, vinyl, vinyloxy, and epoxy groups.

According to this embodiment, since the liquid crystal layer includes the ferroelectric liquid crystal, alignment of the liquid crystal layer can be made uniform along with the nematic liquid crystal, and stability of orientation can be improved. Further, by including the reactive mesogen material in the liquid crystal layer, the orientation rate of the liquid crystal layer is increased, and the angle of orientation is increased, so that the optical characteristics can be improved.

[ Liquid crystal layer _ 2nd Example ]

The liquid crystal layer according to embodiments of the present invention may include a non-ferroelectric liquid crystal and a ferroelectric liquid crystal.

According to an embodiment of the present invention, the non-ferroelectric liquid crystal may include a nematic liquid crystal having negative anisotropy. In this case, the ferroelectric liquid crystal may account for about 0.1 wt% to about 30 wt% of the total amount of the liquid crystal layer. When the ferroelectric liquid crystal is about 0.1% by weight or less of the total amount of the liquid crystal layer, the liquid crystal orientation of the liquid crystal layer may be unstable. In addition, when the ferroelectric liquid crystal exceeds about 30 wt% of the total amount of the liquid crystal layer, the viscosity of the liquid crystal layer increases and the response speed of the display device including the liquid crystal layer may be slowed down. Preferably, the ferroelectric liquid crystal may be about 10% by weight of the total amount of the liquid crystal layer.

According to an aspect, the liquid crystal layer may further include a reactive mesogenic material. In this case, the liquid crystal layer may comprise about 0.1% to about 30% by weight of the ferroelectric liquid crystal, about 0.01% to about 3% by weight of the reactive mesogenic material, and a nematic liquid crystal having extra negative dielectric anisotropy .

The components, structures and examples of the nematic liquid crystal, ferroelectric liquid crystal and reactive mesogen material having the negative anisotropy described in this embodiment are substantially the same as those described above, and detailed description thereof will be omitted.

According to another embodiment of the present invention, the non-ferroelectric liquid crystal may include a nematic liquid crystal having positive anisotropy and a nematic liquid crystal having negative anisotropy. In this case, the liquid crystal layer may comprise a nematic liquid crystal having a negative dielectric anisotropy of about 70 wt% to about 99.9 wt%. The liquid crystal layer may further comprise a mixture of nematic liquid crystal and ferroelectric liquid crystal having a dielectric anisotropy in an amount of about 0.1 wt% to about 30 wt%.

Wherein the mixture of nematic liquid crystal and ferroelectric liquid crystal having positive anisotropy comprises a nematic liquid crystal having a dielectric anisotropy in an amount of about 1 wt% to 90 wt% and a ferroelectric liquid crystal in an amount of about 10 wt% to about 99 wt% can do.

According to an aspect, the liquid crystal layer may further include a reactive mesogenic material. In this case, the liquid crystal layer may comprise a mixture of nematic liquid crystal and ferroelectric liquid crystal having a dielectric anisotropy in an amount of about 0.1 wt% to about 30 wt%, about 0.01 wt% to 3 wt% of a reactive mesogenic material, And a nematic liquid crystal having extra negative anisotropy.

The components, structures and examples of negative anisotropic nematic liquid crystal, positive anisotropic nematic liquid crystal, ferroelectric liquid crystal, and reactive mesogenic material described in this embodiment are substantially the same as those described above, Description thereof will be omitted.

According to this embodiment, since the liquid crystal layer includes the ferroelectric liquid crystal, alignment of the liquid crystal layer can be made uniform along with the non-ferroelectric liquid crystal, and stability of alignment can be improved. Further, by including the reactive mesogen material in the liquid crystal layer, the orientation rate of the liquid crystal layer is increased, and the angle of orientation is increased, so that the optical characteristics can be improved.

Hereinafter, a method for manufacturing the liquid crystal layer will be briefly described.

[Production method of liquid crystal composition]

According to an embodiment of the present invention, the liquid crystal layer can be produced by mixing a nematic liquid crystal having negative anisotropy, a nematic liquid crystal having positive dielectric anisotropy, and a ferroelectric liquid crystal. Wherein the liquid crystal layer comprises a nematic liquid crystal having a negative dielectric anisotropy of about 70 wt% to about 99.9 wt%, a mixture of a nematic liquid crystal and a ferroelectric liquid crystal having a dielectric anisotropy in an amount of about 0.1 wt% to about 30 wt% . Wherein the mixture of nematic liquid crystals and ferroelectric liquid crystals having positive anisotropy comprises a nematic liquid crystal having a dielectric anisotropy in an amount of about 1% by weight to 90% by weight, and a mixture of about 10% to about 99% Liquid crystal.

According to an aspect, the liquid crystal layer may further include a reactive mesogenic material. In this case, the liquid crystal layer may contain a mixture of nematic liquid crystal and ferroelectric liquid crystal having a dielectric anisotropy of about 0.01 wt% to 3 wt% of a reactive mesogenic material and an amount of about 0.1 wt% to about 30 wt% And a nematic liquid crystal having a negative dielectric anisotropy of?

According to another embodiment of the present invention, the liquid crystal layer can be manufactured by mixing a nematic liquid crystal and a ferroelectric liquid crystal having negative anisotropy. More specifically, a nematic liquid crystal having a negative dielectric anisotropy of about 70 wt% to about 99.9 wt% can be prepared by mixing about 0.1 wt% to about 30 wt% of a ferroelectric liquid crystal.

According to an aspect, the liquid crystal layer may further include a reactive mesogenic material. In this case, the liquid crystal layer may comprise about 0.01 wt.% To about 3 wt.% Of the reactive mesogenic material, the 0.1 wt.% To about 30 wt.% Of the ferroelectric liquid crystal and the nematic liquid crystal having extra negative dielectric anisotropy .

In the mixing process, the process temperature may be a temperature at which the largest amount of the liquid crystal layer exhibits isotropic characteristics. According to embodiments of the present invention, the mixing process temperature may be performed at a temperature ranging from about 90 ° C to about 100 ° C. The temperature range may be a temperature range when the nematic liquid crystal having negative dielectric anisotropy exhibits isotropic properties. In the present embodiment, the mixing of the liquid crystal layers is performed within a temperature range of about 90 캜 to about 100 캜, but the present invention does not limit the mixing temperature of the liquid crystal layer.

Hereinafter, the electrical characteristics of the liquid crystal layer will be described.

4 is a graph showing electrical characteristics of a liquid crystal layer according to an embodiment of the present invention. The x-axis in FIG. 1 represents time, the unit is seconds, and the y-axis represents a voltage to be applied, and its unit is volt [V].

When a voltage is applied to the liquid crystal layer manufactured by the above-described manufacturing method, as shown in FIG. 4, it shows an invisible peak in the liquid crystal layer containing only a nematic liquid crystal. This peak is due to ferroelectric liquid crystal. Accordingly, in the liquid crystal layer, the nematic liquid crystal and the ferroelectric liquid crystal are not in the form of the compound but in the form of a mixture, and the nematic liquid crystal exhibits its inherent characteristics and the ferroelectric liquid crystal can exhibit its inherent characteristics. Thus, the nematic liquid crystal and the ferroelectric liquid crystal can reinforce and / or interfere with each other's motion.

Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples. However, the following examples are provided for illustrating the present invention, and the present invention is not limited by the following examples, and various modifications and changes may be made.

Liquid crystal display

≪ Example 1 >

A second display panel including a first display panel including a first electrode having a first slit of a cubic pattern and a second electrode having a second slit of a cubic pattern; A liquid crystal display device including a liquid crystal layer filled was prepared. The liquid crystal display was fabricated in a patterned vertical alignment (PVA) mode.

The liquid crystal layer was prepared from a liquid crystal composition obtained by mixing 90% by weight of MLC 6608 (DELTA n = 0.084, DELTA = = -4.3) and 10% by weight of KFLC 3 (DELTA n = 0.18) The thickness of the liquid crystal layer of the liquid crystal display was 3.8 mu m.

≪ Examples 2 to 4 >

The liquid crystal display devices of Examples 2 to 4 were fabricated in the same manner as in Example 1 except for the thickness of the liquid crystal layer. The thicknesses of the liquid crystal layers of Examples 2 to 4 are shown in Table 1 below.

≪ Example 5 >

A second display panel including a first substrate including a first substrate and a first electrode having a first slit in a cubic pattern, a second substrate having a second substrate and a second electrode having a second slit in a cubic pattern, 1 and a liquid crystal layer filling between the second display panels. The liquid crystal display was manufactured in the PVA mode.

The liquid crystal layer was prepared from a liquid crystal composition obtained by mixing 99% by weight of MLC 6608 (Δn = 0.084, Δε = -4.3) of Merck and 1% by weight of KFLC 3 (Δn = 0.18) The thickness of the liquid crystal layer of the liquid crystal display device was 4.3 mu m.

≪ Examples 6 to 8 >

The liquid crystal display devices of Examples 6 to 8 were manufactured in the same manner except for the mixing ratio between Example 5, MLC 6608 in the liquid crystal layer, and KFLC 3. The mixing ratio between MLC 6608 and KFLC 3 in the liquid crystal layer is shown in Table 1 below.

≪ Example 9 >

A second display panel including a first substrate including a first substrate and a first electrode having a first slit in a cubic pattern, a second substrate having a second substrate and a second electrode having a second slit in a cubic pattern, 1 and a liquid crystal layer filling between the second display panels. The liquid crystal display was manufactured in the PVA mode.

The liquid crystal layer contained 90 wt% of MLC 6608 (DELTA n = 0.084, DELTA = -4.3) of Merck Co., 5 wt% of ZKC-5085 (DELTA n = 0.16, DELTA epsilon = 12) of Chisso Co., KFLC 3 (? N = 0.18) were mixed at 100 占 폚. The thickness of the liquid crystal layer of the liquid crystal display device was 4.3 mu m.

≪ Comparative Example 1 &

A second display panel including a first substrate including a first substrate and a first electrode having a first slit in a cubic pattern, a second substrate having a second substrate and a second electrode having a second slit in a cubic pattern, 1 and a liquid crystal layer filling between the second display panels. The liquid crystal display was manufactured in the PVA mode.

The liquid crystal layer used was 100% by weight of MLC 6608 (DELTA n = 0.084, DELTA epsilon = -4.3) of Merck. The thickness of the liquid crystal layer was 4.3 mu m.

≪ Comparative Examples 2 and 3 >

The liquid crystal display devices of Comparative Examples 2 and 3 were manufactured in the same manner as in Comparative Example 1 except for the thickness of the liquid crystal layer. The thicknesses of the liquid crystal layers of Comparative Examples 2 and 3 are shown in Table 1 below.

Liquid crystal layer Liquid crystal layer thickness
[Mu m] MLC 6608 [wt%]
(Negative nematic liquid crystal) KFLC 3 [wt%]
(Ferroelectric liquid crystal) ZKC-5085 [wt%]
(Positive nematic liquid crystal) Example 1 90 10 0 3.8 Example 2 90 10 0 4.0 Example 3 90 10 0 4.3 Example 4 90 10 0 4.5 Comparative Example 1 100 0 0 4.3 Comparative Example 2 100 0 0 4.5 Comparative Example 3 100 0 0 4.8 Example 5 99 One 0 4.3 Example 6 95 5 0 4.3 Example 7 80 20 0 4.3 Example 8 70 30 0 4.3 Example 9 90 5 5 4.3

Permeability evaluation

5A to 5E are graphs comparing transmittances of the liquid crystal display devices of the first to fourth embodiments with the liquid crystal display devices of the first to third comparative examples. FIG. 5F is a graph comparing transmittances of liquid crystal display devices of Comparative Examples 1, 3, and 9. FIG.

5A to 5C are graphs showing transmittances according to applied voltages. 5A to 5C are voltage applied in units of [V] and the y-axis shows the transmittance.

Referring to FIG. 5A, the liquid crystal display devices of Examples 1 to 4 exhibit excellent overall transmittance as compared with Comparative Examples 1 to 3. More specifically, FIG. 5B selectively shows the transmittances of Example 4 and Comparative Example 2 in FIG. 5A. Referring to FIG. 5B, it was observed that the transmittance of Example 4 was superior to that of Comparative Example 2 at the same liquid crystal layer thickness of 4.5 μm. FIG. 5C selectively shows the transmittances of the fourth and the third comparative examples in FIG. 5A. Referring to FIG. 5C, it was observed that the transmittance of Example 4 was superior when Example 4 having the highest transmittance among Examples 1 to 4 and Comparative Example 3 having the highest transmittance among Comparative Examples 1 to 3 were compared.

5D and 5E are graphs showing transmittance according to the thickness of the liquid crystal layer after applying a voltage of 7V to the liquid crystal display devices of Examples 1 to 4 and the liquid crystal display devices of Comparative Examples 1 to 3. FIG. 5D is a graph showing the transmittance according to the thickness of the liquid crystal layer and FIG. 5E is a graph showing the transmittance according to the product (DELTA nD) of the thickness d of the liquid crystal layer and the refractive index DELTA n of the liquid crystal layer FIG. 5D and FIG. 5E, the unit of length is x [mu m], and the y-axis represents the transmittance.

Referring to FIG. 5D, it can be seen that, in the same liquid crystal layer thickness, the transmittance of the liquid crystal display devices of Examples 1 to 4 is about 17% to about 30% higher than the transmittance of the liquid crystal display devices of Comparative Examples 1 to 3. Referring to FIG. 5E, the transmittance according to DELTA n d is about 9% to about 17% higher than the transmittance of the liquid crystal display devices of Comparative Examples 1 to 3 in the liquid crystal display devices of Examples 1 to 4 .

Referring to FIG. 5F, as described above, the transmittance of the liquid crystal display device of the third embodiment is superior to that of the liquid crystal display device of the first comparative example. In addition, the transmittance of the liquid crystal display device of Example 9 in which 5% by weight of nematic liquid crystal ZKC-5085 having positive dielectric anisotropy was put is also superior to that of the liquid crystal display device of Comparative Example 1.

As a result of the evaluation described above, the ferroelectric liquid crystals in the liquid crystal layers of Examples 1 to 4 and 9 lead the liquid crystal molecules to be able to orient uniformly and stably, so that the liquid crystal display devices of Examples 1 to 4 and Example 9 And the transmittance is superior to that of the liquid crystal display devices of Comparative Examples 1 to 3.

Rate of response speed

6A to 6D are graphs for comparing the response speeds of the liquid crystal display devices of the first to fourth embodiments and the liquid crystal display devices of the first to third comparative examples. FIG. 6F is a graph comparing the response speeds of the liquid crystal display devices of Comparative Examples 1, 3, and 9. FIG.

6A and 6B are graphs showing response speeds depending on applied voltages. 6A and 6B shows the applied voltage in units of [V] and the y-axis shows the response speed.

Referring to FIG. 6A, it can be seen that the response speed of the liquid crystal display devices of Examples 1 to 4 is not much slower than the response speed of the liquid crystal display devices of Comparative Examples 1 to 3. Since the liquid crystal layers of Examples 1 to 4 contain the ferroelectric liquid crystal, the viscosity of the liquid crystal layer is increased and seems to be slightly slower than the response speed of the liquid crystal display devices of Comparative Examples 1 to 3.

6B is selectively shown for checking the response speed according to the voltage of Example 3 showing the maximum transmittance among Examples 1 to 4 and Comparative Example 3 showing maximum transmittance among Comparative Examples 1 to 3. Referring to FIG. 6B, it can be seen that the response speed of Example 3 is higher than that of Comparative Example 3, when comparing the response speeds of Example 3 and Comparative Example 3, which are excellent in transmittance.

6C and 6D are graphs showing the response speed depending on the thickness of the liquid crystal layer after applying a voltage of 7 V to the liquid crystal display devices of Examples 1 to 4 and the liquid crystal display devices of Comparative Examples 1 to 3. 6C is a graph showing the response speed depending on the thickness of the liquid crystal layer, and FIG. 6D is a graph showing the response (response) according to the product (DELTA nD) of the thickness d of the liquid crystal layer and the refractive index DELTA n of the liquid crystal layer This graph shows the speed. 6C and 6D are lengths in units of [mu m], and the y-axis is the response speed in units of [ms].

Referring to FIG. 6C, the response speed of Example 1 having a liquid crystal layer thickness of about 3.8 mu m is about 18 ms, and in order to obtain a response speed of about 18 ms in comparative examples, the liquid crystal layer thickness should be at least 4.3 mu m . Referring to FIG. 6D, the response speed of the liquid crystal display devices of Examples 1 to 4 is about 22% to about 24% higher than the response speed of the liquid crystal display devices of Comparative Examples 1 to 3, % Faster.

Referring to FIG. 6E, the response speed of the liquid crystal display device of the third embodiment is faster than that of the liquid crystal display device of the comparative example 1, as described above. In addition, it can be seen that the response speed of the liquid crystal display device of Example 9 in which the nematic liquid crystal ZKC-5085 having positive dielectric anisotropy is 5% by weight is also faster than the response speed of the liquid crystal display device of Comparative Example 1.

The liquid crystal display devices of Examples 1 to 4 and Example 9 exhibited a response speed corresponding to the applied voltage and a response speed according to the product of the thickness of the liquid crystal layer and the refractive index of the liquid crystal layer, Even though the liquid crystal is included, a response speed faster than those of Comparative Examples 1 to 3 can be obtained by including a liquid crystal layer having an appropriate thickness and refractive index. Therefore, the liquid crystal display devices of Examples 1 to 4 and Example 9 not only have a quick response speed, but also the liquid crystal molecules can be stably and uniformly aligned with the ferroelectric liquid crystal.

Evaluation of transmittance and response speed according to the amount of ferroelectric liquid crystal

FIG. 7A is a graph showing the transmittance of the liquid crystal display devices of Examples 5 to 8, and FIG. 7B is a graph illustrating the response speed of the liquid crystal display devices of Examples 5 to 8.

Referring to FIG. 7A, it was found that the higher the amount of the ferroelectric liquid crystal in the liquid crystal layer, the better the transmittance. However, referring to FIG. 7B, as the amount of ferroelectric liquid crystal in the liquid crystal layer increases, the response speed is reduced to about two times. Therefore, in the present embodiments, it is preferable that the ferroelectric liquid crystal in the liquid crystal composition does not exceed 30% by weight of the total amount of the whole composition.

texture ( texture ) evaluation

FIGS. 8A to 8C and FIGS. 9A to 9C are textures of the liquid crystal display devices of Comparative Examples 1, 3, and 9. FIG.

Comparative Example 1, Example 3 and Example 9 are substantially the same liquid crystal display devices except for the composition ratio of the liquid crystal layer. For ease of explanation, the composition ratios thereof are described again in Table 2. [

Liquid crystal layer Liquid crystal layer thickness
[Mu m] MLC 6608 [wt%]
(Negative nematic liquid crystal) KFLC 3 [wt%]
(Ferroelectric liquid crystal) ZKC-5085 [wt%]
(Positive nematic liquid crystal) Comparative Example 1 100 0 0 4.3 Example 3 90 10 0 4.3 Example 9 90 5 5 4.3

After a voltage of 7 V was applied to the liquid crystal display devices of Comparative Example 1, Example 3 and Example 9, the cross polarizer plate was rotated to obtain white images and black images.

The textures of Figures 8A-8C are white images under crossed polarizer plates. More specifically, the white images show images formed when the angle between the liquid crystal molecules of the crossed polarizer and the liquid crystal layer is 45 ° and the light passes through the liquid crystal layer. This can be confirmed by the following equation (1).

<Formula 1>

In the formula 1, T is the transmittance,? Is the angle between the polarizing plate and the liquid crystal molecules,? N is the birefringence value, d is the thickness of the liquid crystal layer, and? In the above equation (1), when? Is 45, the value of sin ² has the highest value, and the transmittance is the highest.

8A to 8C are textures of Comparative Examples 1, 3, and 9, respectively. Referring to FIG. 8A, defects appear to be black at the edges of the slit or at the boundary of the slit. Referring to FIG. 8B, it can be seen that much defects have disappeared at the edge portion of the slit as compared with FIG. 8A. Referring to FIG. 8C, not only the edge portions of the slit? But also the defects at the boundary of the slit are removed.

The textures of Figures 9A-9C are black images under crossed polarizer plates. More specifically, the black images are obtained when the angle between the liquid crystal molecules of the crossed polarizer and the liquid crystal layer is 0 °, and the polarized plate of the rotated upper part has polarized light perpendicular to the polarized light that has passed through the liquid crystal layer, . In the above equation (1), when? = 0, the value of sin ^{2 has} a value of 0, and the transmittance becomes zero.

9A to 9C are textures of Comparative Examples 1, 3, and 9, respectively. Referring to FIG. 9A, a light leakage phenomenon is observed at the edge portions of the slit or the boundary of the slit. Referring to FIGS. 9B and 9C, it can be seen that the light leakage phenomenon is largely eliminated at the edge portion and the boundary of the slit as compared with FIG. 9A.

In the case of the liquid crystal layer including the ferroelectric material, the orientation of the liquid crystal molecules in the liquid crystal layer is uniform and stable compared to the liquid crystal layer not including the ferroelectric material, thereby improving the brightness of the liquid crystal display device.

FIGS. 10A and 10B are graphs showing the gray levels of the textures of Comparative Examples 1, 3, and 9. FIG. Figs. 10A and 10B evaluate the gray level at 256 (2 ⁸ ), gray closer to black toward 0, and dark gray at 0 to 256 levels.

FIG. 10A shows the gray levels of the textures of FIGS. 8A-8C, many of which are seen near 256 of the gray level with white images. The comparative example 1 of FIG. 8A shows a lot of gray levels of about 200 to 230, and it can be seen that the width of the peak is wide. 8B is much seen at a gray level of about 240 to 250 and its peak width is narrower than the peak width of Comparative Example 1. [ It can be seen that Example 9 of FIG. 8C shows a large amount at a gray level of about 230 to 250, and its peak width is narrower than the peak width of Comparative Example 1. FIG.

Fig. 10B shows the gray levels of the textures of Figs. 9A-9C, many of which are shown near black levels of gray levels. The comparative example 1 of FIG. 9A shows a large amount of gray level of about 30 to 50, and it can be seen that the width of the peak is wide. It can be seen that Example 3 of FIG. 9B shows a lot of gray levels between about 0 and 20, and the width of the peaks is narrower than the peak width of 1 for comparison. 9C shows a large amount at a gray level of about 0 to 30, and the width of the peak is narrower than the peak width of Comparative Example 1. [

10A and 10B, in the case of a liquid crystal layer including a ferroelectric substance, the orientation of liquid crystal molecules in the liquid crystal layer is uniform and stable as compared with a liquid crystal layer not including a ferroelectric substance, The brightness can be improved.

FIGS. 11A and 11B are graphs showing transmittances of the textures of Comparative Examples 1, 3, and 9, respectively, at predetermined intervals. FIGS. 11A and 11B are graphs showing transmittance of the texture of Comparative Example 1, Example 3, and Example 9 at a predetermined interval including the electrode portion and the slit portion.

11A is a graph showing an experiment on white textures of Comparative Examples 1, 3, and 9. Referring to FIG. 11A, in Comparative Example 1, the transmittance of a portion of the slit, It can be seen that it goes down to about 50 or less. The transmittance of Example 3 and Example 9 was higher than that of Comparative Example, and the transmittance of the dark portion was superior to that of Comparative Example 1,

11B is an experimental graph of black textures of Comparative Example 1, Example 3 and Example 9. Referring to FIG. 11B, in Comparative Example 1, light leakage occurs at the edges of the slit or at the boundary of the slit, Has a transmittance of about 60%. On the other hand, in Examples 3 and 9, it can be seen that the transmittance as a whole is lower than that of Comparative Example 1, and the maximum transmittance does not exceed 60. [

11A and 11B, in the case of a liquid crystal layer including a ferroelectric substance, the orientation of liquid crystal molecules in the liquid crystal layer is uniform and stable as compared with a liquid crystal layer not containing a ferroelectric substance, As shown in FIG.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood. It is therefore to be understood that the above-described embodiments are illustrative and not restrictive in every respect.

100: first display panel 110: first substrate
120: first electrode 170: first orientation plate
200: second display panel 220: second electrode
270: second orientation plate 300: liquid crystal layer

Claims (15)

A first substrate;
A second substrate facing away from the first substrate;
A liquid crystal layer disposed between the first and second substrates;
A first electrode disposed between the first substrate and the liquid crystal layer, the first electrode having a first slit; And
And a second electrode disposed between the liquid crystal layer and the second substrate and having a second slit,
Wherein the liquid crystal layer comprises a nematic liquid crystal having negative dielectric anisotropy, a nematic liquid crystal having positive dielectric anisotropy, and a ferroelectric liquid crystal,
Wherein the nematic liquid crystal having negative dielectric anisotropy, the nematic liquid crystal having positive dielectric anisotropy, and the ferroelectric liquid crystal are mixed in the liquid crystal layer in the form of a mixture. The method according to claim 1,
And the first slit and the second slit are not overlapped when the first and second electrodes are viewed in plan view. The method according to claim 1,
Wherein the liquid crystal display device is a patterned vertical alignment (PVA) mode. The method according to claim 1,
A first alignment layer disposed between the first electrode and the liquid crystal layer; And
And a second alignment layer disposed between the second electrode and the liquid crystal layer. 5. The method of claim 4,
Wherein at least one of the first or second alignment layers comprises a reactive mesogen material. The method according to claim 1,
The liquid-
70% by weight to 99.9% by weight of the nematic liquid crystal having negative dielectric anisotropy; And
And 0.1 wt% to 30 wt% of a mixture of the nematic liquid crystal and the ferroelectric liquid crystal having the positive dielectric anisotropy. The method according to claim 6,
Wherein in the mixture of the nematic liquid crystal and the ferroelectric liquid crystal having the positive dielectric anisotropy, the ferroelectric liquid crystal comprises 10% by weight to 99% by weight. The method according to claim 6,
Wherein the liquid crystal layer further comprises a reactive mesogenic material. 9. The method of claim 8,
The liquid-
0.1 wt% to 30 wt% of a mixture of the nematic liquid crystal and the ferroelectric liquid crystal having positive dielectric anisotropy;
0.01% to 3% by weight of said reactive mesogenic material; And
And a nematic liquid crystal having extra negative dielectric anisotropy. A first substrate;
A second substrate facing away from the first substrate;
A liquid crystal layer disposed between the first and second substrates;
A first electrode disposed between the first substrate and the liquid crystal layer, the first electrode having a first slit; And
And a second electrode disposed between the liquid crystal layer and the second substrate and having a second slit,
Wherein the liquid crystal layer includes a non-ferroelectric liquid crystal and a ferroelectric liquid crystal,
Wherein the non-ferroelectric liquid crystal and the ferroelectric liquid crystal are mixed in the liquid crystal layer in the form of a mixture. 11. The method of claim 10,
The liquid-
And 0.1 wt% to 30 wt% of the ferroelectric liquid crystal. 11. The method of claim 10,
In the non-ferroelectric liquid crystal,
A liquid crystal display comprising a nematic liquid crystal having negative dielectric anisotropy. 13. The method of claim 12,
The liquid-
70% by weight to 99.9% by weight of the nematic liquid crystal having negative dielectric anisotropy; And
And 0.1 wt% to 30 wt% of the ferroelectric liquid crystal. 14. The method of claim 13,
Wherein the liquid crystal layer further comprises a reactive mesogenic material. 15. The method of claim 14,
The liquid-
0.1% by weight to 30% by weight of the ferroelectric liquid crystal;
0.01% to 3% by weight of said reactive mesogenic material; And
And a nematic liquid crystal having extra negative dielectric anisotropy.

Images