JP2014066761A - In-plane switching type liquid crystal display element and color filter for in-plane switching type liquid crystal display element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an in-plane switching type liquid crystal display device having high transmittance and excellent viewing angle characteristics.SOLUTION: The in-plane switching type liquid crystal display element includes a liquid crystal drive side substrate having a linear electrode formed in a bend shape, a counter substrate opposing to the liquid crystal drive side substrate, and a liquid crystal layer which is formed between the liquid crystal drive side substrate and the counter substrate and comprises a nematic liquid crystal composition containing a chiral compound; and the display element employs a multi-domain driving system by use of the shape of the linear electrode. Each pixel includes a first region where liquid crystal molecules rotate in a first direction when an electric field is applied, and a second region where the liquid crystal molecules rotate in a second direction different from the first direction, separated by the bend portion of the linear electrode. The area of the first region is larger than the area of the second region.

Description

  The present invention relates to a transverse electric field type liquid crystal display element that is multi-domain driven by the shape of a linear electrode.

  A horizontal electric field type liquid crystal display element has been attracting attention because it can realize a wide viewing angle. In recent years, for the purpose of further improving the viewing angle characteristics, studies have been made on combining multi-domain driving, which is an alignment division technique. In a horizontal electric field type liquid crystal display element that performs multi-domain driving, since two or more regions having different alignment states of liquid crystal molecules exist in the same pixel, at the time of white display or halftone display when observed from an oblique direction The change in color can be improved.

  As a means of multi-domain driving, for example, the comb-shaped electrodes are formed in a “<” shape and the direction of the electric field generated between the comb-shaped electrodes is made different so that the alignment state of the liquid crystal molecules can be changed within the same pixel. A method of forming two or more different regions is known.

  On the other hand, the horizontal electric field mode liquid crystal display element has a problem that the transmittance is low. In a horizontal electric field type liquid crystal display element, for example, a comb electrode is provided on one substrate and an electric field is generated between adjacent comb electrodes, so that the horizontal component of the electric field is small on the comb electrode and the liquid crystal molecules Is difficult to rotate. As a result, the transmittance decreases.

As means for improving the transmittance, for example, a method of adjusting the electrode pattern, the cell gap, the elastic force of the liquid crystal, the type of the liquid crystal and the alignment film, and the like has been proposed. For example, Patent Document 1 discloses means for improving the transmittance by making the cell gap on the comb-tooth electrodes larger than the cell gap between the comb-tooth electrodes. Further, Patent Document 2 uses a liquid crystal to which a chiral agent is added in an IPS mode liquid crystal display element. One of the alignment films is a horizontal alignment film, and the other alignment film is a vertical alignment film. Means for reducing and improving transmittance are disclosed.
In the IPS mode liquid crystal display element described in Patent Document 2, one alignment film is a horizontal alignment film and the other alignment film is a vertical alignment film. When no electric field is applied, liquid crystal molecules are aligned as in the TN mode. However, in a general IPS mode liquid crystal display element, both alignment films are horizontal alignment films.

JP 2010-8862 A JP 2000-267104 A

  The inventors of the present invention have conducted various studies on techniques for improving the transmittance in a horizontal electric field mode liquid crystal display device in which both alignment films are horizontal alignment films and have a general configuration. As a result, chiral compounds have been added. It has been found that the transmittance is improved by using a nematic liquid crystal composition.

However, as a result of repeated studies by the present inventors, when multi-domain driving is performed in a lateral electric field mode liquid crystal display device using a nematic liquid crystal composition to which a chiral compound is added, the following new problem arises. It was found to occur.
That is, since the chiral compound has optical rotation, there is a dominant direction in the direction of rotation of the liquid crystal molecules. Therefore, in two or more regions having different alignment states of liquid crystal molecules in the same pixel, the liquid crystal molecules are easily rotated when an electric field is applied, and the transmittance is different. If the transmittance is different in each region, the color changes when the horizontal electric field mode liquid crystal display element is observed from an oblique direction, although the multi-domain driving is a technique for compensating the viewing angle dependency.

  The present invention has been made in view of the above problems, and a main object of the present invention is to provide a horizontal electric field type liquid crystal display element having high transmittance and excellent viewing angle characteristics.

  In order to achieve the above object, the present invention covers a first base material, a linear electrode formed by bending on the first base material, and the linear electrode on the first base material. A liquid crystal driving side substrate having the formed first alignment film, a second base material, a counter substrate having a second alignment film formed on the second base material, the liquid crystal driving side substrate and the counter substrate And a liquid crystal layer including a nematic liquid crystal composition containing a chiral compound, and a multi-domain driving liquid crystal display device according to the shape of the linear electrode. Having a first region in which liquid crystal molecules rotate in a first direction when an electric field is applied, and a second region in which liquid crystal molecules rotate in a second direction different from the first direction, with the bent portion of the linear electrode as a boundary, The area of the first region is larger than the area of the second region, Providing transverse electric field type liquid crystal display device that.

  In the present invention, it is possible to improve the transmittance by using a nematic liquid crystal composition containing a chiral compound. In the present invention, since the area of the first region is larger than the area of the second region, the transmittance of the first region and the second region can be made uniform, and the viewing angle characteristics can be further improved. Is possible.

  The present invention also includes a transparent substrate, a light shielding portion formed on the transparent substrate and having an opening having a bent shape, and a colored layer formed in the opening on the transparent substrate. A color filter for a horizontal electric field mode liquid crystal display element used in a horizontal electric field mode liquid crystal display element that is multi-domain driven according to the shape of the electrode, wherein each opening corresponding to each pixel of the horizontal electric field mode liquid crystal display element includes: A first opening region corresponding to a first region in which liquid crystal molecules rotate in a first direction when an electric field is applied to the lateral electric field mode liquid crystal display element with the bent portion of the opening as a boundary, and the liquid crystal molecules in the first direction. Has a second opening region corresponding to a second region rotating in a different second direction, and the area of the first opening region is larger than the area of the second opening region. Color filter for display element Subjected to.

  The color filter for a horizontal electric field mode liquid crystal display element of the present invention makes the transmittance of the first region and the second region uniform by making the area of the first opening region larger than the area of the second opening region. It can be suitably used for a horizontal electric field mode liquid crystal display element capable of

  The inventor achieves an effect that a lateral electric field type liquid crystal display device having high transmittance and excellent viewing angle characteristics can be obtained.

It is a schematic sectional drawing which shows an example of the horizontal electric field system liquid crystal display element of this invention. It is a schematic sectional drawing which shows the other example of the horizontal electric field system liquid crystal display element of this invention. It is a schematic diagram for demonstrating multi-domain drive. It is a schematic plan view which shows an example of the pixel and electrode in the horizontal electric field type liquid crystal display element of this invention. It is a schematic plan view which shows the other example of the pixel and electrode in the horizontal electric field type liquid crystal display element of this invention. It is a schematic diagram for demonstrating the 1st area | region and 2nd area | region in the horizontal electric field type liquid crystal display element of this invention. It is a schematic plan view which shows the other example of the pixel and electrode in the horizontal electric field type liquid crystal display element of this invention. It is a schematic plan view which shows an example of the color filter for horizontal electric field system liquid crystal display elements of this invention. It is a schematic sectional drawing which shows an example of the color filter for horizontal electric field system liquid crystal display elements of this invention, and is AA sectional view taken on the line of FIG. It is a schematic plan view which shows an example of the opening part of the light-shielding part in the color filter for horizontal electric field system liquid crystal display elements of this invention. It is a schematic plan view which shows the other example of the opening part of the light-shielding part in the color filter for horizontal electric field type liquid crystal display elements of this invention. It is a schematic plan view which shows the pixel and electrode in the horizontal electric field type liquid crystal display element of an Example. It is a graph which shows the voltage-transmitted light quantity characteristic of the horizontal electric field type liquid crystal display element of the reference | standard 1 and the sample 1-1. It is a graph which shows the voltage-transmitted-light quantity characteristic of the reference | standard 2 and the horizontal electric field type liquid crystal display element of the sample 2-1.

  Hereinafter, the horizontal electric field type liquid crystal display element and the color filter for the horizontal electric field type liquid crystal display element of the present invention will be described in detail.

A. Horizontal electric field type liquid crystal display element The horizontal electric field type liquid crystal display element of the present invention includes a first base material, a linear electrode formed by bending on the first base material, and the linear shape on the first base material. A liquid crystal driving side substrate having a first alignment film formed so as to cover the electrodes, a second base material, a counter substrate having a second alignment film formed on the second base material, and the liquid crystal driving side A liquid crystal layer formed between a substrate and the counter substrate and including a nematic liquid crystal composition containing a chiral compound, and a lateral electric field mode liquid crystal display element that is multi-domain driven by the shape of the linear electrode, Each pixel has a first region in which liquid crystal molecules rotate in a first direction when an electric field is applied, and a second region in which liquid crystal molecules rotate in a second direction different from the first direction, with the bent portion of the linear electrode as a boundary. And the area of the first region is larger than the area of the second region. Is also large.

The horizontal electric field type liquid crystal display element of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic sectional view showing an example of a horizontal electric field mode liquid crystal display element of the present invention, which is an example of an IPS mode liquid crystal display element. In the horizontal electric field mode liquid crystal display element 1 illustrated in FIG. 1, a liquid crystal layer 30 including a nematic liquid crystal composition to which a chiral compound is added is sandwiched between a liquid crystal driving side substrate 10 and a counter substrate 20. The liquid crystal driving side substrate 10 is formed by bending the first base material 2, the first base material 2, the plurality of linear electrodes 3 arranged in a comb-teeth shape, and the lines on the first base material 2. And a first alignment film 4 formed so as to cover the electrode 3. The counter substrate 20 includes a second base material 11 and a second alignment film 12 formed on the second base material 11. The first alignment film 4 of the liquid crystal driving side substrate 10 and the second alignment film 12 of the counter substrate 20 are both so-called horizontal alignment films, and are arranged so that the alignment treatment direction such as the rubbing direction is substantially parallel. Yes. In this horizontal electric field type liquid crystal display element 1, when a voltage is applied to the linear electrodes 3, an electric field is generated between the linear electrodes 3 as indicated by the lines of electric force L.

  FIG. 2 is a schematic cross-sectional view showing another example of the horizontal electric field mode liquid crystal display element of the present invention, which is an example of an FFS mode liquid crystal display element. In the horizontal electric field type liquid crystal display element 1 illustrated in FIG. 2, a liquid crystal layer 30 including a nematic liquid crystal composition to which a chiral compound is added is sandwiched between a liquid crystal driving side substrate 10 and a counter substrate 20. The liquid crystal driving side substrate 10 is bent on the first base material 2, the entire surface electrode 3 a formed on the first base material 2, the insulating layer 5 formed on the entire surface electrode 3 a, and the insulating layer 5. It has a plurality of linear electrodes 3b formed and arranged in a comb shape, and a second alignment film 4 formed on the insulating layer 5 so as to cover the linear electrodes 3b. The counter substrate 20 includes a second base material 11 and a second alignment film 12 formed on the second base material 11. The first alignment film 4 of the liquid crystal driving side substrate 10 and the first alignment film 12 of the counter substrate 20 are both horizontal alignment films and are arranged so that the alignment processing directions are substantially parallel. In the horizontal electric field mode liquid crystal display element 1, when a voltage is applied to the entire surface electrode 3a and the linear electrode 3b, an electric field is generated between the entire surface electrode 3a and the linear electrode 3b as indicated by the lines of electric force L.

In such a lateral electric field type liquid crystal display device, the lateral component of the electric field is small in the vicinity of the linear electrode, particularly in the vicinity of the linear electrode and in the vicinity of the counter substrate. In the present invention, the chiral compound is used as the nematic liquid crystal composition. It is presumed that the addition of the liquid crystal molecules located in the vicinity of the linear electrode facilitates the rotation. The reason why the transmittance is increased by the addition of the chiral compound is not clear, but as a result of the study by the present inventors, the transmittance is improved when the chiral compound is added, whereas the case where the racemate is added. Therefore, it is considered that liquid crystal molecules located in the vicinity of the linear electrode are easily rotated by adding a chiral compound, and as a result, the transmittance is improved.
Therefore, in the present invention, by adding the chiral compound to the nematic liquid crystal composition, it is possible to improve the transmittance in the horizontal electric field type liquid crystal display device.

FIG. 3 is a schematic diagram for explaining the multi-domain driving by the shape of the linear electrode. In FIG. 3, the linear electrode 3 is formed to be bent in a “<” shape. When no electric field is applied, the liquid crystal molecules 31 are aligned along the alignment treatment direction d as indicated by the broken lines in the figure. When an electric field is applied to the liquid crystal layer, the liquid crystal molecules 31 rotate approximately parallel to the substrate surface because the liquid crystal molecules 31 try to align along the electric fields E1 and E2 generated between the electrodes 3. At this time, the directions of the electric fields E1 and E2 generated between the linear electrodes 3 differ depending on the angle of the extending direction of the linear electrode 3 with respect to the alignment processing direction d. Therefore, in the region where the extending direction of the linear electrode 3 forms an angle of + θ with respect to the alignment processing direction d with the bent portion r of the linear electrode 3 as a boundary, the liquid crystal molecules 31 rotate counterclockwise, In a region where the extending direction of the electrode 3 forms an angle of −θ with respect to the alignment processing direction d, the liquid crystal molecules 31 rotate clockwise.
As described above, in a horizontal electric field mode liquid crystal display element driven by multi-domain, there are regions in which the alignment state of liquid crystal molecules is different in the same pixel. That is, one pixel includes a first region in which liquid crystal molecules rotate in a first direction when an electric field is applied, and a second region in which liquid crystal molecules rotate in a second direction different from the first direction, with the bent portion of the linear electrode as a boundary. And having a region.

  Here, since the chiral compound has optical rotation, there is a dominant direction in the direction of rotation of the liquid crystal molecules. Therefore, the first region and the second region, which have different rotation directions of the liquid crystal molecules when an electric field is applied, have a difference in the ease of rotation of the liquid crystal molecules, and the transmittance is different. For example, when the chiral compound exhibits dextrorotatory properties and the clockwise rotation direction is dominant, the rotation direction of the liquid crystal molecules when an electric field is applied is counterclockwise in the first region and clockwise in the second region. In this case, since the liquid crystal molecules easily rotate clockwise, the liquid crystal molecules hardly rotate counterclockwise in the first region when an electric field is applied, and the liquid crystal molecules easily rotate clockwise in the second region. As a result, the transmittance of the first region is lower than that of the second region. If the transmittance is different between the first region and the second region, the multi-domain driving is a technique for compensating the viewing angle dependency, but the color is changed when the lateral electric field mode liquid crystal display element is observed from an oblique direction. Taste, brightness, etc. will change.

FIG. 4 is a schematic plan view showing an example of a pixel in the horizontal electric field mode liquid crystal display element of the present invention. In the horizontal electric field mode liquid crystal display element of the present invention, as illustrated in FIG. 4, the pixel P has a first liquid crystal molecule 31 rotating in the first direction when an electric field is applied, with the bent portion r of the linear electrode 3 as a boundary. The first region 32 and the liquid crystal molecules 31 have a second region 33 that rotates in a second direction different from the first direction, and the area of the first region 32 is larger than the area of the second region 33.
For example, when the chiral compound exhibits dextrorotatory properties and the clockwise rotation direction is dominant, the rotation direction of the liquid crystal molecules 31 when an electric field is applied is left in the first region 32 as illustrated in FIG. When the second region 33 is clockwise, the liquid crystal molecules 31 are likely to rotate clockwise, and the liquid crystal molecules 31 are less likely to rotate counterclockwise in the first region 32 when an electric field is applied. However, since the area of the first region 32 is larger than the area of the second region 33, the transmittance of the first region 32 and the second region 33 can be made uniform.

  In FIG. 4, the region where the liquid crystal molecules 31 rotate counterclockwise when an electric field is applied is the first region 32, and the region where the liquid crystal molecules 31 rotate clockwise is the second region 33. The rotation direction of the liquid crystal molecules in the two regions is not particularly limited as long as they are different from each other. Although not shown, the region where the liquid crystal molecules rotate clockwise when an electric field is applied is the first region, and the liquid crystal molecules rotate counterclockwise The area to be used may be the second area. As will be described later, the rotation directions of the liquid crystal molecules in the first region and the second region are appropriately selected according to the optical rotation of the nematic liquid crystal composition to which the chiral compound is added.

  Therefore, in the present invention, since the area of the first region is larger than the area of the second region, the transmittance of the first region and the second region can be made uniform. Therefore, the viewing angle characteristics can be further improved.

  Here, “multi-domain drive by the shape of the linear electrode” means that the linear electrode is formed in a bent shape, for example, a “<”, so that liquid crystal is applied in the same pixel when an electric field is applied. This means that there are two or more regions having different molecular orientation states.

  A “pixel” is a minimum unit constituting an image. For example, when one pixel is composed of three sub-pixels of red, green, and blue, one sub-pixel is referred to as a pixel in the present invention.

  Hereinafter, each structure of the liquid crystal display element of this invention is demonstrated.

1. Pixel Each pixel in the present invention has a first region in which liquid crystal molecules rotate in a first direction when an electric field is applied, and a second direction in which liquid crystal molecules rotate in a second direction different from the first direction, with the bent portion of the linear electrode as a boundary. The area of the first region is larger than the area of the second region.

  Here, the “bent portion of the linear electrode” refers to a portion where the linear electrode is bent. As illustrated in FIG. 4, a line connecting the bent portions r of the adjacent linear electrodes 3 becomes a boundary between the first region 32 and the second region 33.

  The shape of the pixel differs depending on the shape of the linear electrode and is appropriately selected. For example, a “<” shape as shown in FIG. 4 and a rectangular shape as shown in FIG.

Each pixel has a first region and a second region in which the rotation directions of liquid crystal molecules are different from each other when an electric field is applied. The rotation direction of the liquid crystal molecules in the first region and the second region is appropriately selected according to the optical rotation of the nematic liquid crystal composition to which the chiral compound is added.
For example, in the lateral electric field type liquid crystal display device of the present invention, even if the nematic liquid crystal composition does not form a helical structure when no electric field is applied, if the liquid crystal layer is thickened, the nematic liquid crystal composition has a chiral compound because it has a chiral compound. Come to form. In this way, when the liquid crystal layer is thick and a spiral structure is formed, if the nematic liquid crystal composition exhibits dextrorotatory properties, it can be said that the liquid crystal molecules are likely to rotate clockwise. In this case, a region where liquid crystal molecules rotate counterclockwise when an electric field is applied may be a first region, and a region where liquid crystal molecules rotate clockwise may be a second region. On the other hand, in the above case, when the nematic liquid crystal composition exhibits a left-handed rotation, it can be said that the liquid crystal molecules easily rotate counterclockwise. In this case, a region where liquid crystal molecules rotate clockwise when an electric field is applied may be a first region, and a region where liquid crystal molecules rotate counterclockwise may be a second region.

  In the present invention, the first region and the second region are determined as follows. That is, first, as illustrated in FIGS. 6A and 6B, a plurality of linear electrodes 3 are formed in parallel, and the angle of the extending direction of the linear electrodes 3 with respect to the alignment processing direction d is + θ. A certain first horizontal electric field type liquid crystal display element for measurement and a second horizontal electric field type liquid crystal display element for measurement in which the angle of the extending direction of the linear electrode 3 with respect to the alignment processing direction d is −θ are respectively produced. At this time, the angle of the extending direction of the linear electrode with respect to the cell gap and the alignment treatment direction is set within a general range. Next, an electric field E is applied to the first measurement lateral electric field mode liquid crystal display element and the second measurement lateral electric field mode liquid crystal display element, and the amount of transmitted light is measured. At this time, in the first measurement lateral electric field mode liquid crystal display element and the second measurement lateral electric field mode liquid crystal display element, the rotation direction of the liquid crystal molecules 31 at the time of applying the electric field is different, and the amount of transmitted light is different for the reason described above. Subsequently, among the first measurement lateral electric field type liquid crystal display element and the second measurement lateral electric field type liquid crystal display element, an area corresponding to the measurement lateral electric field type liquid crystal display element with a small amount of transmitted light is defined as the first area. A region corresponding to the horizontal electric field type liquid crystal display element for measurement with a large amount is defined as a second region.

The area ratio between the first region and the second region may be appropriately selected so that the area of the first region is larger than the area of the second region and the transmittance of the first region and the second region is uniform. . Specifically, the ratio of the area of the second region to the area of the first region is preferably in the range of 0.5 or more and less than 1.0, and is in the range of 0.8 or more and less than 1.0. Is more preferable.
As illustrated in FIG. 4, the pixel P usually has one first region 32 and one second region 33.

  As a method of making the area of the first region larger than the area of the second region, for example, a method of making the length y1 of the first region 32 longer than the length y2 of the second region 33 as shown in FIG. As shown in FIG. 7, a method of making the width x1 of the first region 32 wider than the width x2 of the second region 33, or the like can be given. Among these, the method of making the length of the first region longer than the length of the second region is preferable. This is because the areas of the first region and the second region can be easily adjusted while maintaining the aperture ratio and the luminance.

2. Liquid crystal drive side substrate The liquid crystal drive side substrate used in the present invention covers the first base material, the linear electrode formed by bending on the first base material, and the linear electrode on the first base material. And a first alignment film formed on the substrate.
Hereinafter, each configuration of the liquid crystal driving side substrate will be described.

(1) Linear electrode The linear electrode used in the present invention is formed by being bent on the first substrate. In the lateral electric field mode liquid crystal display element of the present invention, the linear electrode has a shape depending on the shape of the linear electrode. Multi domain drive.
The linear electrode is formed by bending and is not particularly limited as long as it has a shape that enables multi-domain driving, and can be a known shape. For example, the shape of “ku” can be used.
The angle of the extending direction of the linear electrode with respect to the alignment processing direction may be a common angle in a horizontal electric field mode liquid crystal display element that performs multi-domain driving depending on the shape of the linear electrode.
As the material, forming method, and film thickness of the linear electrode, known materials, forming methods, and film thicknesses can be applied.

(2) First alignment film Examples of the first alignment film used in the present invention include a horizontal alignment film such as a rubbing film.
As the material, the forming method, and the film thickness of the first alignment film, known materials, forming methods, and film thicknesses can be applied.

(3) 1st base material The 1st base material used for this invention supports said linear electrode and 1st alignment film. A 1st base material will not be specifically limited if generally used as a base material of a horizontal electric field system liquid crystal display element, For example, a glass plate, a plastic plate, etc. are mentioned.

(4) Other Configurations The configuration of the liquid crystal driving side substrate in the present invention is appropriately selected according to the IPS mode and the FFS mode, and the one generally used for a horizontal electric field mode liquid crystal display element is applied. be able to. For example, in the FFS mode liquid crystal display element, the entire surface electrode 3a may be formed in addition to the linear electrode 3b as shown in FIG.

3. Liquid Crystal Layer The liquid crystal layer used in the present invention includes a nematic liquid crystal composition containing a chiral compound and is formed between a liquid crystal driving side substrate and a counter substrate.
Hereinafter, the nematic liquid crystal composition and the liquid crystal layer will be described separately.

(1) Nematic liquid crystal composition The nematic liquid crystal composition used in the present invention contains a chiral compound.
Hereinafter, each component contained in the nematic liquid crystal composition used in the present invention will be described.

(A) Chiral compound The chiral compound used in the present invention exhibits optical rotation as a whole.
Here, “the chiral compound exhibits optical activity as a whole” means that when only one kind of chiral compound is added, the chiral compound exhibits optical activity, and two or more kinds of chiral compounds Is added, it means that a mixture of all chiral compounds contained in the nematic liquid crystal composition exhibits optical rotation. For example, when two or more kinds of chiral compounds are contained and a chiral compound having a reverse optical rotation, that is, a chiral compound exhibiting dextrorotation and a chiral compound exhibiting levorotation are contained, 2 A mixture composed of more than one kind of chiral compound only needs to exhibit optical activity.

  Further, the optical activity of the entire chiral compound is such that the nematic liquid crystal composition does not form a helical structure when no electric field is applied in a lateral electric field type liquid crystal display device. If the nematic liquid crystal composition forms a helical structure when no electric field is applied, it cannot be driven by a lateral electric field. Therefore, it is preferable that the optical activity of the entire chiral compound is relatively weak.

  In addition, for the reasons described above, the chiral pitch of the entire chiral compound is preferably relatively long, and the longer is more preferable. If the chiral pitch is long, the content of the chiral compound can be allowed to some extent, which is advantageous for the preparation of a nematic liquid crystal composition.

  The chiral compound may have liquid crystallinity or may not have liquid crystallinity. In addition, when the chiral compound has liquid crystallinity, it may have smectic properties or may not have smectic properties.

  The chiral compound used in the present invention is not particularly limited as long as it has the above properties, and can be appropriately selected from known chiral compounds. Hereinafter, specific examples of the chiral compound will be described.

(I) Chiral compound represented by the following general formula (1) Examples of the chiral compound used in the present invention include a compound represented by the following general formula (1).
^{R 1 -A 1 -Z 1 -A 2} -Z 2 - (A 3 -Z 3) m - (A 4) n -R 2 (1)
(In the above formula (1), R ¹ is an achiral group and is a saturated or unsaturated alkyl group having 5 to 11 carbon atoms which may be substituted with a halogen atom.
R ² is a chiral group and is a group represented by the following general formula (2).
—O—C ^* H (CH ₃ ) —COO—R ³ (2)
(In the above formula (2), R ³ is a saturated or unsaturated alkyl group having 1 to 8 carbon atoms which may be substituted with a halogen atom. * Indicates a chiral center.)
A ^{1 to} A ⁴ are each independently a 1,4-cyclohexylene group, an optionally substituted 1,4-phenylene group, a pyridine-2,5-diyl group, or a pyrimidine-2,5. -A diyl group.
Z ^{1 to} Z ³ are each independently a single bond or an ester bond.
m and n are each independently 0 or 1, and m ≦ n. )

  The chiral compound represented by the above formula (1) has a chiral group represented by the above formula (2), and has a lactic acid ester moiety at the chiral site. Such a chiral compound is preferable because the chiral pitch is relatively small.

  The chiral compound represented by the formula (1) may have liquid crystallinity or may not have liquid crystallinity.

In the above formula (1), R ¹ is a non-chiral group and is a saturated or unsaturated alkyl group having 5 to 11 carbon atoms which may be substituted with a halogen atom.
Although carbon number should just be 5-11, 6-10 are preferable especially and 7-8 are more preferable. This is because if the number of carbon atoms is larger than the above range, the solubility of the chiral compound is lowered, the synthesis becomes difficult, and the cost increases. On the other hand, when the number of carbon atoms is less than the above range, the liquid crystal phase is hardly expressed, and there is a possibility that the liquid crystal alignment is hindered or the effect of improving the transmittance cannot be obtained.
The alkyl group may be substituted with a halogen atom or may not be substituted with a halogen atom, but among them, it is preferable that the alkyl group is not substituted with a halogen atom. When the alkyl group is substituted with a halogen atom, the halogen atom is preferably a fluorine atom.
The alkyl group is linear or branched.
The alkyl group may be saturated or unsaturated, but is preferably saturated. In unsaturated alkanes other than cyclic unsaturated alkanes, unsaturated alkanes are more reactive than saturated alkanes, and their materials change due to long-term storage / driving and temperature changes. This is because there is a risk of deterioration.

In the above formula (1), R ² is a chiral group having one or more chiral centers, and is a group represented by the above formula (2).

In the above formula (2), R ³ is a saturated or unsaturated alkyl group having 1 to 8 carbon atoms which may be substituted with a halogen atom.
Although carbon number should just be 1-8, 1-6 are preferable especially and 2-4 are more preferable.
The alkyl group may be substituted with a halogen atom or may not be substituted with a halogen atom, but among them, it is preferable that the alkyl group is not substituted with a halogen atom. When the alkyl group is substituted with a halogen atom, the halogen atom is preferably a fluorine atom.
The alkyl group is linear, branched or cyclic.

In the above formula (1), A ^{1 to} A ⁴ are each independently 1,4-cyclohexylene group, optionally substituted 1,4-phenylene group, pyridine-2,5-diyl group. Or a pyrimidine-2,5-diyl group.

The 1,4-phenylene group may have a substituent, and examples of the substituent include —CH ₃ , —CF ₃ , and a halogen atom.

The 1,4-phenylene group can have 1 to 4 substituents, and among them, it is preferable to have 1 or 2 substituents.
When there is one substituent, the substituent is preferably —CH ₃ , a fluorine atom or a chlorine atom, and more preferably —CH ₃ or a fluorine atom. On the other hand, when there are two substituents, it is preferable that any substituent is a fluorine atom. In this case, as the position of the two substituents, it is preferable that the adjacent carbon atoms of the 1,4-phenylene group are respectively substituted with fluorine atoms. When the 1,4-phenylene group is substituted with adjacent carbon atoms, specifically, fluorine atoms at the 2-position and 3-position, respectively, and the 1,4-phenylene group is symmetrically substituted, a transverse electric field system In the liquid crystal display element, the transmittance tends to be high.

When two or more of A ^{1 to} A ⁴ are 1,4-phenylene groups, the two or more 1,4-phenylene groups preferably have 1 to 3 substituents in total.
When the total number of substituents is 3, crystallization of the nematic liquid crystal composition is suppressed, and in the horizontal electric field mode liquid crystal display element, the transmittance tends to increase and the response speed tends to increase. In this case, the position of the substituent is preferably such that each substituent is bonded to a nearby carbon atom in two or more 1,4-phenylene groups. Among them, one 1,4-phenylene group preferably has two or more substituents, and one 1,4-phenylene group has two substituents, and is adjacent to the 1,4-phenylene group. More preferably, the other 1,4-phenylene group has one substituent. This is because the regularity of the molecular arrangement can be relaxed and the crystallization can be suppressed by positioning the substituents close to each other.

Moreover, when two of A ^{1 to} A ⁴ are 1,4-phenylene groups, it is preferable that either one of the two 1,4-phenylene groups has a substituent. When three of A ^{1 to} A ⁴ are 1,4-phenylene groups, it is preferable that the 1,4-phenylene group located in the middle of the three 1,4-phenylene groups has a substituent. When ^four of A ^{1 to} A ⁴ are 1,4-phenylene groups, any one of the 1,4-phenylene groups located in the middle among the four 1,4-phenylene groups has a substituent. Is preferred. This is because the addition of the chiral compound can suppress the nematic liquid crystal composition from being easily crystallized.

In the above formula (1), Z ^{1 to} Z ³ are each independently a single bond or an ester bond.

  In the above formula (1), m and n are each independently 0 or 1, and m ≦ n.

Specific examples of the chiral compound represented by the above formula (1) include compounds represented by the following formula. Here, in the following formula, R ¹ and R ² are the same as in the above formula (1). In the following formula, X ¹ is CH ₃ , F or Cl, and X ² is CH ₃ or Cl.

  Specific examples of the chiral compound represented by the above formula (1) include the chiral compounds shown in Tables 1 and 2 below. In the table, dextrorotatory is indicated by + and levorotatory is indicated by-.

  Specific examples of the chiral compound represented by the above formula (1) include the following chiral compounds.

  As a chiral compound represented by the said Formula (1), 1 type may be used independently and 2 or more types may be mixed and used.

  The chiral compound represented by the above formula (1) can be synthesized by a known synthesis method, for example, by the method described in International Publication No. 2010/031431.

(Ii) Chiral compounds represented by the following general formulas (3) and (4) Examples of the chiral compound used in the present invention include compounds represented by the following general formulas (3) and (4).

(In the above formulas (3) and (4), R ¹¹ and R ¹³ are non-chiral groups, which may be substituted with a halogen atom, a C4-C18 saturated or unsaturated alkyl group or alkoxy group. It is an alkyl group.
R ¹² and R ¹⁴ are chiral groups and are groups represented by the following general formula (5).
—O— (CH ₂ ) _m —C ^* H (Y ¹ ) — (COO) _n —R ¹⁵ (5)
(In the above formula (5), R ¹⁵ is a C1-C10 saturated or unsaturated alkyl group or alkoxyalkyl group which may be substituted with a halogen atom. Y ¹ represents —CH ₃ or fluorine. Represents an atom, m is 0 or 1. n is 0 or 1. * indicates a chiral center.)
X ^{1 to} X ¹² and X ^{13 to} X ²⁴ each independently represent —CH ₃ , —CF ₃ , a halogen atom or a hydrogen atom. However, one or more of X ^{1 to} X ¹² and one or more of X ^{13 to} X ²⁴ are each independently —CH ₃ , —CF ₃ or a halogen atom.
p is 0 or 1, one of q and r is 0 and the other is 1.
One of s and t is 0 and the other is 1, and one of u and v is 0 and the other is 1. However, s and v are not 1 at the same time. )

  The chiral compounds represented by the above formulas (3) and (4) are suitable because the chiral pitch is relatively small due to their structure.

The chiral compound represented by the above formulas (3) and (4) may have liquid crystallinity or may not have liquid crystallinity.
Hereinafter, the chiral compound represented by the above formula (3) and the chiral compound represented by the above formula (4) will be described separately.

(Chiral compound represented by the above formula (3))
In the above formula (3), p is 0 or 1, one of q and r is 0 and the other is 1. When p = 0, q = 1, r = 0, a chiral compound represented by the following general formula (3-1). When p = 0, q = 0, r = 1, the following general formula (3-2) ), When p = 1, q = 1, r = 0, the chiral compound represented by the following general formula (3-3), when p = 1, q = 0, r = 1 Becomes a chiral compound represented by the following general formula (3-4).

(In the above formulas (3-1) to (3-4), R ¹¹ , R ¹² , and X ^{1 to} X ¹² are the same as in the above formula (3).)

In the above formula (3), R ¹¹ is an achiral group, which is a saturated or unsaturated alkyl group or alkoxyalkyl group having 4 to 18 carbon atoms which may be substituted with a halogen atom.
Although carbon number should just be 4-18, 6-18 are preferable especially and 6-12 are more preferable. This is because if the number of carbon atoms is larger than the above range, the solubility of the chiral compound is lowered, the synthesis becomes difficult, and the cost increases. On the other hand, when the number of carbon atoms is less than the above range, the liquid crystal phase is hardly expressed, and there is a possibility that the liquid crystal alignment is hindered or the effect of improving the transmittance cannot be obtained.
The alkyl group or alkoxyalkyl group may be substituted with a halogen atom or may not be substituted with a halogen atom, but is preferably not substituted with a halogen atom. When the alkyl group or alkoxyalkyl group is substituted with a halogen atom, the halogen atom is preferably a fluorine atom.
The alkyl group or alkoxyalkyl group is linear or branched.
The alkyl group or alkoxyalkyl group may be saturated or unsaturated, but is preferably saturated. In unsaturated alkanes other than cyclic unsaturated alkanes, unsaturated alkanes are more reactive than saturated alkanes, and their materials change due to long-term storage / driving and temperature changes. This is because there is a risk of deterioration.
R ¹¹ may be an alkyl group or an alkoxyalkyl group, but is preferably an alkyl group.

In the above formula (3), R ¹² is a chiral group having one or more chiral centers, and is a group represented by the above formula (5).

In the above formula (5), R ¹⁵ is a saturated or unsaturated alkyl or alkoxyalkyl group having 1 to 10 carbon atoms which may be substituted with a halogen atom.
The alkyl group or alkoxyalkyl group may be substituted with a halogen atom or may not be substituted with a halogen atom, but is preferably not substituted with a halogen atom. When the alkyl group or alkoxyalkyl group is substituted with a halogen atom, the halogen atom is preferably a fluorine atom.
The alkyl group or alkoxyalkyl group is linear, branched or cyclic.
R ¹⁵ may be an alkyl group or an alkoxyalkyl group, but is preferably an alkyl group.

In the above formula (5), Y ¹ represents —CH ₃ or a fluorine atom. Of these, —CH ₃ is preferred. This is because the synthesis of the chiral compound is easy, can be stably produced, and a nematic liquid crystal composition can be obtained at low cost.
In the above formula (3), R ¹² is a chiral group. Therefore, in the above formula (5), when Y ¹ is —CH ₃ and n = 0, R ⁵ is not —CH ₃ .

  In the above formula (5), when m = 0, the carbon atom at the 1st position becomes a chiral center, and when m = 1, the carbon atom at the 2nd position becomes a chiral center.

In the above formula (3), X ^{1 to} X ¹² each independently represent —CH ₃ , —CF ₃ , a halogen atom or a hydrogen atom. However, one or more of X ^{1 to} X ¹² are each independently —CH ₃ , —CF ₃ or a halogen atom.
When all of X ^{1 to} X ¹² are hydrogen atoms, the solubility of the chiral compound is lowered, so that the synthesis and purification of the chiral compound is difficult and the cost is increased. On the other hand, when one or more of X ^{1 to} X ¹² are —CH ₃ , —CF _3, or a halogen atom as in the present invention, the solubility of the chiral compound in the solvent is increased, and mass synthesis is performed. Purification becomes possible.

In particular, in the above formulas (3-1) and (3-3), any one or more other than X ¹⁰ and X ¹² are each independently —CH ₃ , —CF ₃ or a halogen atom. preferable. This is because the chiral compound has better solubility than the case of X ¹⁰ or X ¹² when it has a substituent other than X ¹⁰ and X ¹² . This is presumably because the X ¹⁰ and X ¹² positions are less distorted by substituents than the other positions.

One benzene ring can have 1 to 4 substituents, and among them, it is preferable to have 1 or 2 substituents. When there is one substituent, the substituent is preferably —CH ₃ , a fluorine atom or a chlorine atom, and more preferably —CH ₃ or a fluorine atom. On the other hand, when there are two substituents, it is preferable that any substituent is a fluorine atom. In this case, as the positions of the ^two substituents, it is preferable that the fluorine atoms are respectively substituted on the adjacent carbon atoms of the benzene ring as in the case where X ¹ and X ² are fluorine atoms, for example. When two fluorine atoms are substituted on adjacent carbon atoms of the benzene ring and the benzene ring is symmetrically substituted, the transmittance tends to be high in the horizontal electric field type liquid crystal display device.

  Moreover, in the case of the chiral compound represented by the above formula (3), it is preferable to have 1 to 2 substituents in total.

As the position of the substituent, it is preferable that the benzene ring located in the middle of 3 to 4 aromatic rings directly bonded has a substituent. Specifically, in the above formula (3-1), the benzene ring to which X ^{1 to} X ⁴ are bonded preferably has a substituent. In the above formula (3-3), it is preferable that at least one of the benzene rings to which X ^{1 to} X ⁴ or X ^{5 to} X ⁸ are bonded has a substituent. In the above formulas (3-2) and (3-4), the benzene ring located in the middle has a substituent. The addition of the chiral compound can suppress the nematic liquid crystal composition from being easily crystallized.

  Specific examples of the chiral compound represented by the above formula (3) include chiral compounds represented by the following general formulas (3-5) to (3-8).

(In the above formulas (3-5) to (3-8), R ²² represents —O—C ^* H (CH ₃ ) COOR ²³ or —O— (CH ₂ ) _m —C ^* H (CH ₃ ) R ^23. R ²³ is a saturated or unsaturated alkyl group having 1 to 10 carbon atoms, m is 0 or 1. w is 4 to 18. X ^{41 to} X ⁴⁶ are independently —CH ₃ , — CF ₃ represents a halogen atom or a hydrogen atom, provided that in the above formulas (3-5) and (1-6), any one of X ⁴¹ , X ⁴² , X ⁴⁵ and X ⁴⁶ is —CH ₃ , —CF ₃ or a halogen atom, and the remainder is a hydrogen atom, or two of X ⁴¹ and X ⁴² are a fluorine atom and the remainder is a hydrogen atom, and the above formulas (3-7) and (3-8) in), any one or two -CH ₃ of X ⁴¹ to X ^46, a -CF ₃ or a halogen atom, the remainder is hydrogen A child, or two of X ⁴¹ and X ⁴² or X ⁴³ and X ^44, although a fluorine atom, the remainder is a hydrogen atom.)

w is the same as the carbon number of R ¹¹ in the above formula (3).
R ²³ can be the same as R ¹⁵ in the above formula (5). Among them, R ²³ is preferably a linear or branched saturated alkyl group or a phenylalkyl group.
X ^{41 to} X ⁴⁶ can be the same as X ^{1 to} X ¹² in the above formula (3).

  Specific examples of the chiral compounds represented by the above formulas (3-5) to (3-8) include the chiral compounds shown in Table 1 and the chiral compounds shown in Table 3 below. In the table, dextrorotatory is indicated by + and levorotatory is indicated by-.

  As a chiral compound represented by the said Formula (3), 1 type may be used independently and 2 or more types may be mixed and used.

  The chiral compound represented by the above formula (3) can be synthesized, for example, by the method described in International Publication No. 2010/031431.

(Chiral compound represented by the above formula (4))
In the above formula (4), one of s and t is 0 and the other is 1, and one of u and v is 0 and the other is 1. However, s and v are not 1 at the same time. When s = 0, t = 1, u = 1, v = 0, a chiral compound represented by the following general formula (4-1); when s = 0, t = 1, u = 0, v = 1 Is a chiral compound represented by the following general formula (4-2). When s = 1, t = 0, u = 1, and v = 0, the chiral compound is represented by the following general formula (4-3). .

(In the above formulas (4-1) to (4-3), R ¹³ , R ¹⁴ and X ^{13 to} X ²⁴ are the same as those in the above formula (4).)

In the above formula (4), R ¹³ and R ¹⁴ are the same as R ¹¹ and R ¹² in the above formula (3), respectively.

In the above formula (4), X ^{13 to} X ²⁴ each independently represent —CH ₃ , —CF ₃ , a halogen atom or a hydrogen atom. However, for the same reason as the chiral compound represented by the above formula (3), one or more of X ^{13 to} X ²⁴ are each independently —CH ₃ , —CF ₃ or a halogen atom.

Among them, since the solubility is good like the chiral compound represented by the above formula (3), any one or more other than X ²² and X ²⁴ is independently —CH ₃ , —CF ₃ or halogen. An atom is preferred.

One benzene ring can have 1 to 4 substituents, and among them, it is preferable to have 1 or 2 substituents. When there is one substituent, the substituent is preferably —CH ₃ , a fluorine atom or a chlorine atom, and more preferably —CH ₃ or a fluorine atom. On the other hand, when there are two substituents, it is preferable that any substituent is a fluorine atom. In this case, the position of the two substituents is adjacent to the benzene ring for the same reason as in the chiral compound represented by the above formula (3), for example, when X ¹⁷ and X ¹⁸ are fluorine atoms. It is preferable that each carbon atom is substituted with a fluorine atom.

Moreover, in the case of the chiral compound represented by the above formula (4), it is preferable to have 1 to 3 substituents in total.
When the total number of substituents is 3, crystallization of the nematic liquid crystal composition is suppressed, and in the horizontal electric field mode liquid crystal display element, the transmittance tends to increase and the response speed tends to increase. In this case, the position of the substituent is preferably such that each substituent is bonded to a nearby carbon atom in two or more benzene rings. Among them, it is preferable that one benzene ring has two or more substituents, and one benzene ring has two substituents, and another benzene ring adjacent to the benzene ring has one substituent. It is more preferable to have a group. This is because the regularity of the molecular arrangement can be relaxed and the crystallization can be suppressed by positioning the substituents close to each other.

As the position of the benzene ring having a substituent, since crystallization can be suppressed similarly to the chiral compound represented by the above formula (3), the benzene ring located in the middle of the four directly bonded aromatic rings. The ring preferably has a substituent. Specifically, in the above formulas (4-1) and (4-2), at least one of the benzene rings to which X ^{13 to} X ¹⁶ or X ^{17 to} X ²⁰ are bonded may have a substituent. preferable. In the above formula (4-3), the benzene ring located in the middle has a substituent.

  Specific examples of the chiral compound represented by the above formula (4) include chiral compounds represented by the following general formulas (4-4) to (4-6).

(In the above formulas (4-4) to (4-6), R ²⁴ represents —O—C ^* H (CH ₃ ) COOR ²⁵ or —O— (CH ₂ ) _m —C ^* H (CH ₃ ) R ^25. R ²⁵ is a saturated or unsaturated alkyl group having 1 to 10 carbon atoms, m is 0 or 1. w is 4 to 18. X ^{51 to} X ⁵⁶ are independently —CH ₃ , — CF ₃ represents a halogen atom or a hydrogen atom, provided that any one or two of X ^{51 to} X ⁵⁶ are —CH ₃ , —CF ₃ or a halogen atom, and the remainder is a hydrogen atom, or X ⁵¹ And X ⁵² , or two of X ⁵³ and X ⁵⁴ are fluorine atoms and the rest are hydrogen atoms, or X ⁵² is —CH ₃ , two of X ⁵³ and X ⁵⁴ are fluorine atoms, and the rest are hydrogen An atom.)

w is the same as the carbon number of R ¹³ in the above formula (4).
R ²⁵ can be the same as R ¹⁵ in the above formula (5). Among these, R ²⁵ is preferably a linear or branched saturated alkyl group or a phenylalkyl group.
X ^{51 to} X ⁵⁶ can be the same as X ^{13 to} X ²⁴ in the above formula (4).

  Specific examples of the chiral compounds represented by the above formulas (4-4) to (4-6) include the chiral compounds shown in Table 2 and the chiral compounds shown in Table 4 below. In the table, dextrorotatory is indicated by + and levorotatory is indicated by-.

  As a chiral compound represented by the said Formula (4), 1 type may be used independently and 2 or more types may be mixed and used.

  The chiral compound represented by the above formula (4) can be synthesized, for example, by the method described in International Publication No. 2010/031431.

(Iii) Content of chiral compound The nematic liquid crystal composition used in the present invention may contain a chiral compound. Among these, when two or more kinds of chiral compounds are contained, it is preferable that a chiral compound having an optical rotation reverse direction is contained. If the content of chiral compound with the same direction of optical rotation is large, the nematic liquid crystal composition may form a helical structure when there is no electric field in a lateral electric field type liquid crystal display device. This is because the nematic liquid crystal composition hardly forms a helical structure in a horizontal electric field mode liquid crystal display element in the absence of an electric field even if the content is large.

  The content of the chiral compound in the nematic liquid crystal composition is such that the desired transmittance can be obtained and multi-domain driving is possible, and the nematic liquid crystal composition has a helical structure when there is no electric field in a horizontal electric field mode liquid crystal display device. If it is a grade which does not form, it will not specifically limit. Specifically, the total content of the chiral compounds is preferably in the range of 1% by mass to 10% by mass in the nematic liquid crystal composition. When the content of the chiral compound is less than the above range, the effect of improving the transmittance may not be sufficiently obtained. On the other hand, when the content of the chiral compound is more than the above range, in the horizontal electric field mode liquid crystal display element When no electric field is applied, the nematic liquid crystal composition may form a helical structure, which may make multi-domain driving difficult, deteriorate the black display, or increase the viscosity of the nematic liquid crystal composition and reduce the response speed. is there.

(B) Other components The nematic liquid crystal composition used in the present invention contains a component exhibiting a nematic phase in addition to the chiral compound. As a component which shows a nematic phase, what is generally used for a nematic liquid crystal composition can be used, and it is not specifically limited.

(C) Nematic liquid crystal composition The nematic liquid crystal composition used in the present invention is not particularly limited as long as it exhibits a nematic phase.

(2) Liquid Crystal Layer The thickness of the liquid crystal layer is not particularly limited as long as it can be driven by a lateral electric field method, but is preferably relatively thin for improving the response speed and low driving voltage. Specifically, the thickness of the liquid crystal layer is preferably in the range of 1.5 μm to 5.0 μm.

  As a method for forming the liquid crystal layer, a method generally used as a method for manufacturing a liquid crystal cell can be used. For example, a vacuum injection method, a liquid crystal dropping method, or the like can be used.

4). Counter substrate The counter substrate used in the present invention has a second base material and a second alignment film formed on the second base material, and faces the liquid crystal driving side substrate.
Note that the second base material and the second alignment film are the same as the first base material and the first alignment film of the liquid crystal driving side substrate, respectively, and thus description thereof is omitted here.
In the lateral electric field type liquid crystal display element of the present invention, the first alignment film of the liquid crystal driving side substrate and the second alignment film of the counter substrate are arranged so that the alignment treatment direction such as the rubbing direction is substantially parallel.
The configuration of the counter substrate is appropriately selected according to the IPS mode and the FFS mode, and those generally used for a horizontal electric field mode liquid crystal display element can be applied. For example, a color filter for a horizontal electric field mode liquid crystal display element described later can be used for the counter substrate.

B. Color filter for horizontal electric field type liquid crystal display element The color filter for horizontal electric field type liquid crystal display element of the present invention comprises a transparent substrate, a light shielding part formed on the transparent substrate and having an opening having a bent shape, and the transparent A color filter for a horizontal electric field mode liquid crystal display element used for a horizontal electric field mode liquid crystal display element having a colored layer formed in the opening on the substrate and driven in a multi-domain manner by the shape of a linear electrode, Each of the openings corresponding to each pixel of the horizontal electric field mode liquid crystal display element has a first direction in which liquid crystal molecules rotate in a first direction when an electric field is applied to the horizontal electric field type liquid crystal display element with the bent portion of the opening as a boundary. A first opening region corresponding to one region and a second opening region corresponding to a second region in which liquid crystal molecules rotate in a second direction different from the first direction, and the area of the first opening region is Second opening area It is characterized by being larger than the area.
Hereinafter, the color filter for the horizontal electric field type liquid crystal display element may be simply referred to as a color filter.

The color filter for a horizontal electric field type liquid crystal display element of the present invention will be described with reference to the drawings.
FIG. 8 is a schematic plan view showing an example of a color filter for a horizontal electric field mode liquid crystal display element of the present invention, and FIG. 9 is a cross-sectional view taken along line AA of FIG. As illustrated in FIGS. 8 and 9, the color filter 50 for a horizontal electric field mode liquid crystal display element includes a light shielding portion 52 having a bent opening 55 on a transparent substrate 51, a red colored layer 53R, and a green color. A colored layer 53 having a colored layer 53G and a blue colored layer 53B is formed. The color filter 50 for a horizontal electric field mode liquid crystal display element is a color filter used for a horizontal electric field mode liquid crystal display element that is multi-domain driven by the shape of a linear electrode as illustrated in FIG. As illustrated in FIG. 8, in the color filter 50 for a horizontal electric field mode liquid crystal display element, the opening 55 included in the light shielding portion 52 corresponds to a pixel of the horizontal electric field mode liquid crystal display element as illustrated in FIG. The first opening region 56 and the liquid crystal molecules corresponding to the first region in which the liquid crystal molecules rotate in the first direction when an electric field is applied to the lateral electric field mode liquid crystal display element with the bent portion s of the opening 55 as a boundary. It has the 2nd opening area | region 57 corresponding to the 2nd area | region rotated in the 2nd direction different from a 1st direction. Further, the area of the first opening region 56 is larger than the area of the second opening region 57.
In FIG. 8, the light shielding portion 52 is indicated by a one-dot chain line.

  According to the color filter of the present invention, the area of the first opening region is larger than the area of the second opening region, so that the transmittance of the first region and the second region can be made uniform. It can use suitably for an element.

  Hereinafter, each configuration of the color filter of the present invention will be described.

1. Light-shielding part The light-shielding part in this invention is formed on a transparent substrate, and is provided with the opening part which has the bent shape. Each opening corresponds to each pixel of a horizontal electric field mode liquid crystal display element that performs multi-domain driving according to the shape of the linear electrode, that is, the opening defines a pixel. Each opening has a first opening region corresponding to a first region in which the liquid crystal molecules rotate in the first direction when the electric field is applied to the lateral electric field type liquid crystal display element with the bent portion of the opening as a boundary, and the liquid crystal molecules are the first. A second opening region corresponding to the second region rotating in a second direction different from the direction, and the area of the first opening region is larger than the area of the second opening region.

  Here, the “bent portion of the opening portion” refers to a portion where the opening portion is bent in a “<” shape, for example, as illustrated in FIG. 10.

  The shape of the opening is a bent shape, and differs depending on the shape of the linear electrode in the horizontal electric field mode liquid crystal display element, and is appropriately selected. For example, the shape of “ku” as shown in FIG.

Each opening has a first opening region and a second region corresponding to a first region and a second region, respectively, having different rotation directions of liquid crystal molecules when an electric field is applied in a lateral electric field mode liquid crystal display element, with a bent portion of the opening as a boundary. It has 2 open areas.
As the area ratio of the first opening region and the second opening region, it is sufficient that the area of the first opening region is larger than the area of the second opening region. In the horizontal electric field mode liquid crystal display element, the first region and the second region are transmitted. It is appropriately selected so that the rate is uniform. Specifically, the ratio of the area of the second opening region to the area of the first opening region can be the same as the ratio of the area of the second region to the area of the first region in the above-described horizontal electric field mode liquid crystal display element. .
As illustrated in FIG. 10, the opening 55 usually has one first opening region 56 and one second opening region 57.

  As a method for making the area of the first opening region larger than the area of the second opening region, for example, the length y3 of the first opening region 56 is made longer than the length y4 of the second opening region 57 as shown in FIG. For example, a method of increasing the width x3 of the first opening region 56 and a width x4 of the second opening region 57 as shown in FIG. Among these, the method of making the length of the first opening region longer than the length of the second opening region is preferable. This is because the areas of the first opening region and the second opening region can be easily adjusted while maintaining the opening ratio.

  As the material, the forming method, and the film thickness of the light shielding portion, known materials, forming methods, and film thicknesses can be applied.

2. Colored layer The colored layer in the present invention is formed in the opening on the transparent substrate.
The colored layer is usually one in which colored layers of a plurality of colors are arranged, and known materials, array patterns, and forming methods can be used as the materials, array patterns, and forming methods.
Further, the area and film thickness of the colored layer are appropriately selected according to the use of the horizontal electric field type liquid crystal display element in which the color filter of the present invention is used.

3. Transparent substrate As the transparent substrate in the present invention, a transparent substrate generally used for a color filter can be used.

4). Other Configurations The color filter of the present invention is not particularly limited as long as it has the above-described colored layer, light-shielding portion, and transparent substrate, and necessary members can be appropriately selected and added. Examples of such a member include a spacer, an overcoat layer, and an alignment film. As the spacer and the overcoat layer, those generally used for color filters can be applied. As the alignment film, the second alignment film in the counter substrate of the horizontal electric field mode liquid crystal display element described above can be used.

5. Applications The color filter of the present invention is used for a horizontal electric field mode liquid crystal display element that is multi-domain driven by the shape of a linear electrode. In a horizontal electric field type liquid crystal display element, the color filter of the present invention is usually used as a counter substrate.
Since the horizontal electric field type liquid crystal display element to which the color filter of the present invention is applied has been described in detail in the above-mentioned “A. Horizontal electric field type liquid crystal display element”, description thereof is omitted here.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

  The following examples illustrate the present invention in more detail.

(Nematic liquid crystal composition)
Nematic liquid crystal compositions were prepared as shown in Table 5 below using chiral compounds I and II shown below.

[Example 1]
(Production of IPS mode liquid crystal display element)
First, a glass substrate on which ITO electrodes were patterned in a comb shape was prepared. As illustrated in FIG. 12, the ITO electrode is formed in a “<” shape so that the extending direction of the linear electrode 3 forms an angle of ± 5 ° with respect to the alignment processing direction d in the alignment film forming process described later. It was formed. Further, the lengths y _A and y _B of the region A and the region B were adjusted to adjust the areas of the region A and the region B in the pixel P.
On this substrate, resin spacers having a circular shape of Φ5.0 μm and a height of 3.0 μm were formed at a pitch of 0.1 mm. Subsequently, a rubbing alignment film material (SE610: Nissan Chemical Industries, Ltd.) was spin-coated at a rotation speed of 1500 rpm for 30 seconds. Thereafter, after drying in an oven at 180 ° C. for 30 minutes, as illustrated in FIG. 12, a rubbing treatment was performed so that the angle of the linear electrode 3 in the extension direction with respect to the alignment treatment direction d was ± 5 °.
Further, a rubbing alignment film material (SE610: Nissan Chemical Industries, Ltd.) was spin-coated at a rotation speed of 1500 rpm for 30 seconds on another glass substrate. Thereafter, the substrate was dried in an oven at 180 ° C. for 30 minutes, and then rubbed.
Next, a sealing material was applied in a square frame shape on the substrate. The nematic liquid crystal composition containing the above-described chiral compound I was applied onto the substrate, and the two substrates were assembled and pressure-bonded so that the directions of the rubbing treatments were parallel to each other.

[Example 2]
(Production of IPS mode liquid crystal display element)
A nematic liquid crystal composition containing the chiral compound II described above was used, and the liquid crystal was the same as in Example 1 except that the angle of the extension direction of the linear electrode 3 with respect to the alignment treatment direction d in FIG. A display element was produced.

[Evaluation]
The amount of light transmitted through the liquid crystal display element was measured by setting a photomultiplier tube (Photomaru) on a polarizing microscope BX51 manufactured by Olympus, converting the light intensity into a voltage value, and measuring the value as the transmitted light amount value (au). Two polarizing plates in a polarizing microscope were set in a crossed Nicol state, and the liquid crystal cell filled with the nematic liquid crystal composition was rotated to a position where the amount of transmitted light was minimized. In this state, a rectangular wave voltage (± 5 V) was applied, and the amount of transmitted light at that time was measured. The results are shown in Table 6 and Table 7. Further, the voltage-transmitted light amount characteristics of the liquid crystal display element in which the area ratio of the region A and the region B is 1: 1 using the chiral compound I in FIG. 13, and the chiral compound II in FIG. The voltage-transmitted light amount characteristics of a liquid crystal display element having an area ratio of 1: 1 are shown.

When the chiral compound was added, the transmittance was improved as compared with the case where the chiral compound was not added.
Further, it was confirmed that by changing the area ratio of the region A and the region B, the transmittance of the region A and the region B becomes uniform and the viewing angle characteristics are improved. Since chiral compounds I and II have opposite optical rotation, liquid crystal display devices using chiral compound I have a large area A, and liquid crystal display devices using chiral compound II have a region B region. It adjusted so that an area might become large.

DESCRIPTION OF SYMBOLS 1 ... Horizontal electric field type liquid crystal display element 2 ... 1st base material 3, 3b ... Linear electrode 3a ... Whole surface electrode 4 ... 1st orientation film 10 ... Liquid crystal drive side substrate 11 ... 2nd base material 12 ... 2nd orientation film 20 ... counter substrate 30 ... liquid crystal layer 31 ... liquid crystal molecule 32 ... first region 33 ... second region 50 ... color filter for lateral electric field type liquid crystal display element 51 ... transparent substrate 52 ... light-shielding part 53 ... colored layer 55 ... opening 56 ... First opening region 57 ... Second opening region d ... Orientation processing direction P ... Pixel

Claims (2)

A liquid crystal driving side having a first base material, a linear electrode formed by bending on the first base material, and a first alignment film formed on the first base material so as to cover the linear electrode A substrate,
A counter substrate having a second base material and a second alignment film formed on the second base material;
A liquid crystal layer formed between the liquid crystal drive side substrate and the counter substrate and including a nematic liquid crystal composition containing a chiral compound, and a lateral electric field mode liquid crystal display element that is multi-domain driven by the shape of the linear electrode Because
Each pixel has a first region in which liquid crystal molecules rotate in a first direction when an electric field is applied, and a second region in which liquid crystal molecules rotate in a second direction different from the first direction, with the bent portion of the linear electrode as a boundary. And
The horizontal electric field mode liquid crystal display element, wherein an area of the first region is larger than an area of the second region. A transparent substrate; a light-shielding portion that is formed on the transparent substrate and includes a bent opening; and a colored layer that is formed in the opening on the transparent substrate. A color filter for a horizontal electric field type liquid crystal display element used in a horizontal electric field type liquid crystal display element driven in a multi-domain,
The openings corresponding to the pixels of the horizontal electric field type liquid crystal display element rotate in the first direction when an electric field is applied to the horizontal electric field type liquid crystal display element with the bent portion of the opening as a boundary. A first opening region corresponding to the first region and a second opening region corresponding to the second region in which the liquid crystal molecules rotate in a second direction different from the first direction;
A color filter for a horizontal electric field mode liquid crystal display element, wherein an area of the first opening region is larger than an area of the second opening region.

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