WO2019116745A1

WO2019116745A1 - Liquid crystal display device and method of manufacture therefor

Info

Publication number: WO2019116745A1
Application number: PCT/JP2018/039627
Authority: WO
Inventors: 幸一井桁; 英博園田; 武徳廣田
Original assignee: 株式会社ジャパンディスプレイ
Priority date: 2017-12-14
Filing date: 2018-10-25
Publication date: 2019-06-20
Also published as: JP2019105784A; JP7038537B2

Abstract

The purpose of the present invention is to prevent an alignment film from peeling off from the curved portion of a flexible liquid crystal display device. Provided is a liquid crystal display device that has a first alignment film 113 formed on a first substrate 100, a second alignment film formed on a second substrate, and a liquid crystal interposed between the first substrate 100 and the second substrate, and can be curved or bent in a second direction with a first direction as a curving axis or bending axis, the liquid crystal display device being characterized in that the first alignment film 113 and the second alignment film are optically aligned using polarized ultraviolet rays, and the direction of the alignment axis AL of the first alignment film 113 and the second alignment film matches the second direction within the range of 0° ± 10°.

Description

Liquid crystal display device and method of manufacturing the same

The present invention relates to a display device, and more particularly to a liquid crystal display device which can be bent, bent and the like.

In a liquid crystal display device, a TFT substrate on which pixels having pixel electrodes, thin film transistors (TFTs), and the like are formed in a matrix, and an opposing substrate are disposed facing the TFT substrate, and liquid crystal is sandwiched between the TFT substrate and the opposing substrate. ing. An image is formed by controlling the light transmittance of liquid crystal molecules for each pixel.

There is an increasing demand for such a liquid crystal display device as a flexible display device which can be bent or bent. A flexible liquid crystal display device uses a thin glass substrate as a substrate or is formed of a resin such as polyimide. If bending or bending is repeated for such a flexible display area, display quality is degraded.

In Patent Document 1, in order to prevent the deterioration of display quality in such a flexible display device, an electrode layer and an alignment film are formed on a TFT substrate, and then a curable liquid crystal composition is applied and cured, and then A liquid crystal display device having a configuration in which liquid crystal is held between an opposing substrate and a TFT substrate is described. In addition, using the photo-alignment film formed by irradiating an ultraviolet-ray as said alignment film is described.

JP, 2015-203720, A

On the TFT substrate, various films such as alignment films, electrodes, wirings, insulating films and the like are formed. Therefore, when the liquid crystal display device is bent or bent, stress occurs in these films. The alignment film is for initially aligning liquid crystal molecules, and there are rubbing processing and photo-alignment processing using polarized ultraviolet light as the alignment processing. The photo-alignment process has advantages such as no influence of foreign substances generated by the rubbing process, or less generation of static electricity.

Although polyimide is used for the alignment film subjected to photo-alignment, when the polyimide is subjected to alignment treatment, the film is broken in the predetermined direction because the polyimide is torn. When the liquid crystal display device having such an alignment film is bent or bent, a phenomenon in which the alignment film is broken and peeled off occurs in a portion subjected to the bending or bending stress. When the alignment film is broken, light leakage occurs in that portion and the display quality is degraded.

An object of the present invention is to provide a liquid crystal display device having a photo-aligned alignment film, which can prevent deterioration of display quality without breaking the alignment film even if stress of bending or bending is applied. It is to realize.

The present invention overcomes the above problems, and the main specific means are as follows.

(1) A first photoalignment film is formed on a first substrate, a second photoalignment film is formed on a second substrate, and a liquid crystal is held between the first substrate and the second substrate A liquid crystal display capable of being bent or bent with the first direction as a bending axis or bending axis, wherein the direction of the alignment axis of the first light alignment film and the second light alignment film is What is claimed is: 1. A liquid crystal display device wherein the first direction coincides with a range of 90 degrees ± 10 degrees.

(2) A method of manufacturing a liquid crystal display device in which liquid crystal is held between a first substrate and a second substrate, and can be curved or bent in a second direction with the first direction as a bending axis or a bending axis A first alignment film is formed on the first substrate, and the first alignment film is photoaligned using polarized ultraviolet light so as to have an alignment axis in the second direction, A second alignment film is formed on the second substrate, and the second alignment film is photoaligned using polarized ultraviolet light so as to have an alignment axis in the second direction. Production method.

(3) A liquid crystal display device in which liquid crystal is held between a first substrate and a second substrate and which can be bent with a first direction as a first bending axis, the first substrate and the first substrate The second substrate has an alignment film, and in the first substrate and the second substrate, the alignment ability of the first region having a first width including the first bending axis to the liquid crystal is A liquid crystal display device characterized in that the alignment film is subjected to alignment treatment with polarized ultraviolet light in portions other than the first region, which is smaller than the alignment ability to the liquid crystal other than the first region.

1 is a plan view of a liquid crystal display to which the present invention is applied. It is a top view which shows the pixel structure of a display area. It is sectional drawing of a display area. It is another example of a pixel electrode. It is a schematic diagram which shows optical orientation. It is a schematic diagram which shows the influence on alignment film intensity | strength by optical alignment. FIG. 1 is a schematic view showing a configuration of Example 1; It is a table | surface which shows the example of the usage aspect of a flexible liquid crystal display device. It is a table | surface which shows the specification relevant to the peeling countermeasure of alignment film. It is a top view which shows the relationship between the curve direction of a liquid crystal display device in case dielectric anisotropy is positive, and a pixel electrode. It is a top view which shows the relationship of the curve direction of a liquid crystal display device, and a pixel electrode in case dielectric anisotropy is negative. It is a top view which shows the relationship between the bending direction of a liquid crystal display device when a dielectric anisotropy is positive, and a pixel electrode. It is a top view which shows the relationship between the bending direction of a liquid crystal display device in case dielectric anisotropy is negative, and a pixel electrode. It is a top view which shows the example of the orientation direction of alignment film in case alignment processing is not performed to alignment film of a bending part. It is a top view which shows the other example of the orientation direction of alignment film in case alignment processing is not carried out to alignment film of a bending part. It is a top view which shows the example of the orientation direction of alignment film in case an alignment film is not formed in a bending part. It is a top view which shows the other example of the orientation direction of alignment film in case an alignment film is not formed in a bending part. FIG. 21 is a plan view showing a first example of the fifth embodiment. FIG. 21 is a plan view showing a second example of the fifth embodiment. FIG. 21 is a plan view showing a third example of the fifth embodiment. FIG. 21 is a plan view showing a fourth example of the fifth embodiment. In the case of a liquid crystal having positive dielectric anisotropy, it is a plan view showing a configuration in the case where the alignment axis of the alignment film is 45 degrees with respect to the bending direction. In the case of a liquid crystal with negative dielectric anisotropy, it is a plan view showing a configuration in the case where the alignment axis of the alignment film is 45 degrees with respect to the bending direction.

The following examples illustrate the invention in detail.

FIG. 1 is a plan view showing an example of a liquid crystal display panel 20 to which the present invention is applied. FIG. 1 shows an example of a liquid crystal display panel 20 used for a mobile phone or a tablet. In FIG. 1, a TFT substrate 100 in which pixels including TFTs and pixel electrodes are arranged in a matrix and a counter substrate 200 on which a black matrix and the like are formed are bonded by a sealing material 50, and between the TFT substrate 100 and the counter substrate 200. The liquid crystal is held.

A display area 30 is formed in a portion where the TFT substrate 100 and the counter substrate 200 overlap. In the display area 30, scanning lines 11 extend in the horizontal direction (x direction) on the TFT substrate 100 and are arranged in the vertical direction (y direction). The video signal lines 12 extend in the vertical direction and are arranged in the horizontal direction. Pixels 13 are formed in a region surrounded by the scanning lines 11 and the video signal lines 12.

In FIG. 1, the TFT substrate 100 is formed to be larger than the counter substrate 200, and the terminal region 40 is formed in a portion where the TFT substrate 100 and the counter substrate 200 do not overlap. A flexible wiring substrate 500 is connected to the terminal region 40 in order to supply signals and power to the liquid crystal display panel 20. The liquid crystal display panel 20 shown in FIG. 1 is configured such that the TFT substrate 100 and the counter substrate 200 are formed of a resin such as polyimide or very thin glass, etc., and can be bent flexibly. Although a display device using the liquid crystal display panel 20 is referred to as a liquid crystal display device in this specification, the liquid crystal display panel 20 and the liquid crystal display device may be used without distinction.

FIG. 2 is a plan view showing the pixel arrangement in the display area 30 of FIG. In FIG. 2, the scanning lines 11 extend in the lateral direction (x direction) and are arranged in the longitudinal direction (y direction). The video signal lines 12 extend in the vertical direction and are arranged in the horizontal direction. A pixel electrode 112 is formed in a region surrounded by the scanning line 11 and the video signal line 12.

The major axis direction of the pixel electrode 112 is inclined at an angle θ with the y direction. The video signal line 12 is inclined by an angle θ with the y direction in accordance with the inclination θ of the pixel electrode 112. The angle θ is, for example, 5 degrees to 15 degrees. An arrow AL in FIG. 2 indicates the alignment direction of the alignment film when the dielectric anisotropy of the liquid crystal is positive. The alignment direction AL of the alignment film is the y direction. The reason for inclining the pixel electrode 112 and the alignment direction AL by the angle θ is to match the rotational direction of the liquid crystal when a voltage is applied to the pixel electrode 112 and to prevent the generation of a domain.

There are positive and negative dielectric anisotropy in liquid crystals. FIG. 2 shows the case where the dielectric anisotropy of the liquid crystal is positive. When the dielectric anisotropy of the liquid crystal of the liquid crystal display device is negative, the alignment direction AL is rotated 90 degrees from the case of FIG. That is, it becomes the x direction of FIG.

In FIG. 2, the semiconductor layer 103 is connected to the video signal line 12 in the through hole 140, passes under the video signal line 12, passes under the scanning line 11, and then bends and passes under the scanning line 11 again. Do. When the semiconductor layer 103 passes under the scanning line 11, a TFT is formed. That is, in FIG. 2, two TFTs are formed in series. At this time, the scanning line 11 has a role of the gate electrode of the TFT.

The semiconductor layer 103 is connected to the contact electrode 107 in the through hole 120. The contact electrode 107 is connected to the pixel electrode 112 in the through hole 130. In FIG. 2, the common electrode 110 is formed in a planar shape except for the through hole 130. A capacitive insulating film 111, which will be described later, is present on the common electrode 110, and a pixel electrode 112 is formed thereon.

The pixel electrode 112 has a slit 1121 and a comb electrode 1122. The pixel electrode 112 may have various shapes depending on the size of the pixel. For example, when the pixel becomes small, the slit 1121 disappears, and the pixel electrode 112 becomes one comb-tooth electrode 1122, that is, a stripe-shaped electrode. On the other hand, when the pixel size is increased, the number of slits 1121 is two or more, and the number of the comb-tooth electrodes 1122 is also three or more. In this specification, even when the number of the comb-tooth electrode 1122 of the pixel electrode 112 is one, it is called a comb-tooth electrode.

FIG. 3 is a cross-sectional view of the liquid crystal display panel corresponding to the cross section AA of FIG. That is, only one TFT is described in FIG. The TFT in FIG. 3 is a so-called top gate type TFT, and as the semiconductor 103 used, LTPS (Low Temperature Poly-Si) is used. On the other hand, when an a-Si (amorphous Si) semiconductor is used, so-called bottom gate TFTs are often used. In the following description, although the case where a top gate TFT is used is described as an example, the present invention can be applied to a case where a bottom gate TFT is used.

In FIG. 3, the TFT substrate 100 and the counter substrate 200 are formed of a resin such as polyimide or a very thin glass plate having a thickness of 0.15 mm or less. The glass plate can be bent flexibly as the plate thickness decreases. When the substrate 100 is formed of a resin such as polyimide, the thickness can be further reduced to 10 μm to 20 μm.

In FIG. 3, a first base film 101 made of SiN and a second base film 102 made of SiO are formed on the TFT substrate 100 by CVD (Chemical Vapor Deposition). The role of the first base film 101 and the second base film 102 is to prevent impurities from the TFT substrate 100 from contaminating the semiconductor layer 103.

The semiconductor layer 103 is formed on the second base film 102. In this semiconductor layer 103, an a-Si film is formed on the second base film 102 by CVD and converted into a poly-Si film by laser annealing. This poly-Si film is patterned by photolithography.

A gate insulating film 104 is formed on the semiconductor film 103. The gate insulating film 104 is an SiO film made of TEOS (tetraethoxysilane) as a raw material. This film is also formed by CVD. A gate electrode 105 is formed thereon. The gate electrode 105 doubles as the scanning line 11 shown in FIG. The gate electrode 105 is formed of, for example, a MoW film. When it is necessary to reduce the resistance of the gate electrode 105 or the scanning line 10, an Al alloy is used.

The gate electrode 105 is patterned by photolithography. During this patterning, an impurity such as phosphorus or boron is doped into the poly-Si layer by ion implantation to form a source S or drain D in the poly-Si layer. Do. In addition, a lightly doped drain (LDD) layer is formed between the channel layer of the poly-Si layer and the source S or the drain D by using a photoresist when patterning the gate electrode 105.

Thereafter, an interlayer insulating film 106 is formed of SiO, covering the gate electrode 105. The interlayer insulating film 106 is to insulate the gate wiring 105 and the contact electrode 107. Through holes 120 for connecting the source portion S of the semiconductor layer 103 to the contact electrode 107 are formed in the interlayer insulating film 106 and the gate insulating film 104. Photolithography for forming the through holes 120 in the interlayer insulating film 106 and the gate insulating film 104 is simultaneously performed.

Contact electrode 107 is formed on interlayer insulating film 106. The contact electrode 107 is connected to the pixel electrode 112 through the through hole 130. The drain D of the TFT is connected to the video signal line 12 through the through hole 140 as shown in FIG.

The contact electrode 107 and the video signal line 12 are simultaneously formed in the same layer. For the contact electrodes 107 and the video signal lines (hereinafter represented by the contact electrodes 107), for example, an AlSi alloy is used to reduce the resistance. Since AlSi alloy generates hillocks and Al diffuses into other layers, for example, a barrier layer of MoW not shown and a cap layer sandwich AlSi.

The inorganic passivation film (insulating film) 108 is covered to cover the contact electrode 107 to protect the entire TFT. The inorganic passivation film 108 is formed by CVD in the same manner as the first base film 101. An organic passivation film 109 is formed to cover the inorganic passivation film 108. The organic passivation film 109 is formed of a photosensitive acrylic resin. The organic passivation film 109 can be formed of a silicone resin, an epoxy resin, a polyimide resin or the like in addition to the acrylic resin. The organic passivation film 109 has a role as a planarizing film and is therefore formed thick. The film thickness of the organic passivation film 109 is 1 to 4 μm, but in most cases it is about 2 μm.

In order to electrically connect the pixel electrode 112 and the contact electrode 107, through holes 130 are formed in the inorganic passivation film 108 and the organic passivation film 109. The organic passivation film 109 uses a photosensitive resin. After application of the photosensitive resin, when the resin is exposed, only the light-exposed part is dissolved in the specific developer. That is, formation of a photoresist can be omitted by using a photosensitive resin. After forming the through holes 130 in the organic passivation film 109, the organic passivation film 109 is completed by baking the organic passivation film at about 230.degree.

Thereafter, ITO (Indium Tin Oxide) to be a common electrode 110 is formed by sputtering, and is patterned so as to remove the ITO from the through holes 130 and the periphery thereof. The common electrode 110 can be formed flat in common to each pixel. Thereafter, SiN to be a capacitive insulating film 111 is formed on the entire surface by CVD. Thereafter, in the through hole 130, a through hole for electrically connecting the contact electrode 107 and the pixel electrode 112 is formed in the capacitive insulating film 111 and the inorganic passivation film 108. Note that the capacitive insulating film 111 is called a capacitive insulating film 111 because a storage capacitance is formed between the common electrode 110 and the pixel electrode 112.

Thereafter, ITO is formed by sputtering and patterned to form a pixel electrode 112. The planar shape of the pixel electrode 112 is described in FIG. An alignment film material is applied on the pixel electrode 112 by flexo printing, inkjet, or the like, and baked to form an alignment film 113. For alignment processing of the alignment film 113, photo alignment by polarized ultraviolet light is used.

When a voltage is applied between the pixel electrode 112 and the common electrode 110, an electric line of force as shown in FIG. 3 is generated. The liquid crystal molecules 301 are rotated by this electric field, and the amount of light passing through the liquid crystal layer 300 is controlled for each pixel to form an image.

In FIG. 3, the counter substrate 200 is disposed with the liquid crystal layer 300 interposed therebetween. A color filter 201 is formed on the inside of the counter substrate 200. In the color filter 201, red, green and blue color filters are formed for each pixel, whereby a color image is formed. A black matrix 202 is formed between the color filter 201 and the color filter 201 to improve the contrast of the image. The black matrix 202 also has a role as a light shielding film of the TFT, and prevents a photocurrent from flowing to the TFT.

An overcoat film 203 is formed to cover the color filters 201 and the black matrix 202. Since the surfaces of the color filter 201 and the black matrix 202 are uneven, the surface is made flat by the overcoat film 203. The overcoat film 203 also has a role of preventing the pigment of the color filter 201 from contaminating the liquid crystal layer 300. An alignment film 113 for determining the initial alignment of the liquid crystal molecules 301 is formed on the overcoat film 203. Similar to the alignment film 113 on the TFT substrate 100 side, the alignment process of the alignment film 113 uses a photoalignment method by polarized ultraviolet light.

The above configuration is an example. For example, the inorganic passivation film 108 in the TFT substrate 100 may not be formed depending on the type. Also, the process of forming the through holes 130 may differ depending on the type.

The shape of the pixel electrode 112 is not limited to that shown in FIG. 2, but may have a structure as shown in FIG. In this case, the slit 1121 is inclined in the lateral direction (x direction) by θ degrees, for example 5 to 15 degrees, and the comb electrode 1122 is also in the lateral direction (x direction) with θ degrees, for example 5 degrees It is inclined by 15 degrees. When a liquid crystal with positive dielectric anisotropy is used, the alignment direction AL of the alignment film is the x direction. That is, it is the same as FIG. 2 in that the comb electrode 1122 forms an angle of θ degrees with the alignment direction AL of the alignment film 113. Therefore, hereinafter, the direction of the pixel electrode 112 is defined as the direction of the comb electrode 1122 in the present specification. Also in the case of FIG. 4, when the dielectric anisotropy is negative, the alignment direction of the alignment film 113 is rotated by 90 degrees and is in the y direction.

As the alignment film 113, a film in which a polyamic acid or a polyamic acid ester is imidized is used. FIG. 5 is a schematic view showing photoalignment. The photoalignment is performed by irradiating the alignment film 113 formed on the substrate 100 with polarized ultraviolet light having a wavelength of about 250 nm. The figure in the center of FIG. 5 shows a state in which ultraviolet light having a polarization axis UVP in the longitudinal direction (y direction) is irradiated so that the alignment film 113 formed on the substrate 100 has the alignment axis in the lateral direction (x direction). It is a top view shown. Hereinafter, the substrate is represented by the TFT substrate 100, but the same applies to the opposite substrate 200. Also, the TFT substrate 100 may be replaced with the liquid crystal display panel 20. The alignment film has a configuration in which polyimides are randomly arranged in all directions as shown in FIG. The figure on the right side of FIG. 5 is a schematic view showing a state in which the polyimide PI having the main chain in the longitudinal direction is irradiated with the ultraviolet light having the polarization axis UVP in the longitudinal direction. In this case, the cyclobutane ring is cleaved by polarized ultraviolet light, and the polyimide PI is cleaved.

On the other hand, the upper drawing of FIG. 5 is a schematic view showing a state in which the polyimide PI having the main chain in the horizontal direction is irradiated with the ultraviolet light having the polarization axis UVP in the vertical direction. In this case, the polyimide is not divided. Then, the alignment film 113 has the alignment axis AL in the lateral direction (x direction) which is a direction in which the polyimide is not divided.

When the substrate on which the alignment film 113 in this state is formed is curved along the y-axis, the polyimide molecules are separated in this direction, so that they are mechanically weak and peeling of the alignment film 113 or the like occurs. On the other hand, when the substrate on which the alignment film 113 in this state is formed is curved along the x-axis, since the polyimide PI is not divided, the mechanical strength is not lowered. It is hard to occur.

FIG. 6 is a plan view showing a state in which ultraviolet light having a polarization axis UVP is applied in the lateral direction (x direction) so that the alignment film 113 formed on the substrate 100 has the alignment axis AL in the longitudinal direction (y direction). It is. The central view of FIG. 6 shows a state in which the end of the substrate is curved in a roll in the x direction with the y direction as the bending axis. When irradiated with such polarized ultraviolet light, the polyimide having a main chain in the lateral direction (x direction) is cleaved by cleavage of the cyclobutane ring.

The structural formula in the upper drawing of FIG. 6 shows a state in which a cyclobutane ring constituting a polyimide having a main chain in the lateral direction (x direction) is cleaved by polarized ultraviolet light. Further, the wavy curve PI shows a state in which the polyimide chain is divided by ultraviolet light. In this case, the polyimide having a main chain in the lateral direction (x direction) is weak in strength both in the lateral direction (x direction) and in the longitudinal direction (y direction).

On the other hand, the figure on the right side of FIG. 6 is a schematic view showing a state in which the ultraviolet light having the polarization axis UVP in the lateral direction is irradiated to the polyimide PI having the main chain in the longitudinal direction. In this case, the polyimide PI is not divided. Then, the alignment film 113 has the alignment axis AL in the longitudinal direction (y direction) in which the polyimide is not divided.

On the other hand, polyimide PI has low strength in the direction perpendicular to the direction of the main chain. The wavy line PI on the right side of FIG. 6 shows a polyimide chain, but the strength is large in the extending direction of the wavy line but weak in the direction perpendicular to the wavy line PI. Therefore, in FIG. 6, the strength of the polyimide is weak in the direction of bending in a roll shape or an S shape, and the alignment film 113 is easily peeled off from the substrate.

FIG. 7 is a schematic view showing the bending direction of the substrate 100 and the direction of the alignment axis AL of the alignment film 113, which show the feature of the present invention. The central view of FIG. 7 shows a state in which the end of the substrate 100 is curved in a roll in the x direction with the y direction as the bending axis. In the central drawing of FIG. 7, in the substrate 100 in which the end is curved in a roll shape, the direction of the polarization axis UVP of polarized ultraviolet light for photo-orienting the alignment film 113 formed on the substrate 100 and the alignment of the alignment film 113 It is a top view which shows the direction of axis AL. The alignment axis UVP of the polarized ultraviolet light is in the longitudinal direction (y direction), and the alignment axis AL of the alignment film 113 subjected to the alignment process by the polarized ultraviolet light is in the lateral direction (x direction).

The upper drawing of FIG. 7 shows a structural formula of a polyimide having a main chain in the lateral direction (x direction), but the polyimide PI having a main chain in this direction does not cleave a cyclobutane ring by polarized ultraviolet light. Therefore, the alignment axis AL of the alignment film 113 is in the x direction. In addition, since the polyimide having a main chain in this direction is strong, the polyimide PI is difficult to peel even if it is curved along the x direction.

The figure on the right side of FIG. 7 shows a structural formula of a polyimide having a main chain in the longitudinal direction (y direction), but in the polyimide having a main chain in this direction, the cyclobutane ring is cleaved by polarized ultraviolet light. Therefore, the polyimide PI has low strength in the longitudinal direction.

A wavy line PI in the central diagram of FIG. 7 indicates that the polyimide PI having a main chain in the lateral direction is not divided. Therefore, even if the alignment film 113 is curved in a roll shape or an S-shape along the lateral direction (x direction), the alignment film 113 is resistant to stress and therefore does not peel off. On the other hand, although the polyimide PI having the main chain in the longitudinal direction is torn, it is weak to stress, but since the substrate 100 is not curved in this direction, peeling of the alignment film 113 does not occur. Therefore, with the configuration as shown in FIG. 7, peeling of the alignment film 113 hardly occurs even when the liquid crystal display device is curved.

Here, that the direction of the alignment axis AL of the alignment film 113 and the bending direction of the liquid crystal display panel are the same direction means that they coincide with each other within 0 ° ± 10 °. This range is more preferably within 0 ° ± 1 °. The same applies to the case where the liquid crystal display panel 20 is bent as described in the second and subsequent embodiments. In other words, it can be said that the direction of the alignment axis AL of the alignment film 113 and the bending axis or bending axis of the liquid crystal display panel coincide within 90 degrees ± 10 degrees. More preferably, this range is within 90 ° ± 1 °.

By the way, various modes exist about the usage aspect of a flexible liquid crystal display device, and the specification of a flexible liquid crystal display device. FIG. 8 is a table showing the usage of the flexible liquid crystal display device. There are cases where the flexible liquid crystal display device is bent and used, or folded and stored. In the case of using in a curved state, in the case of using the end portion in a roll shape, in the case of using an S-shape, or in using a cylinder in some cases. In any of the embodiments, bending stress is generated in the first direction on the substrate and the alignment film, but no bending stress is applied in the direction perpendicular to the first direction.

When it is folded and accommodated, it may be folded in two or in four or more. In the case of three-fold, it can be represented by two-fold. In the case of four-fold or more, it can be represented by four-fold. In the case of four-fold, there are two bending axes, and the first axis and the second axis intersect. If the first axis and the second axis do not intersect, it may be considered in accordance with the two fold.

FIG. 9 shows specifications associated with the alignment film 113 corresponding to the usage mode as shown in FIG. In FIG. 9, in the alignment direction row of the alignment film, when the alignment direction of the alignment film is either vertical or horizontal in the TFT substrate, the alignment direction is single but the alignment direction is oblique. In this case, a plurality of alignment film regions may exist in the TFT substrate. When there are a plurality of alignment film regions, light alignment is performed using a mask.

The direction of the major axis direction of the comb electrode in the pixel electrode becomes a problem in relation to the alignment direction of the alignment film. That is, the direction of the major axis direction of the comb-tooth electrode in the pixel electrode needs to be selected so as not to generate a domain in the liquid crystal layer in relation to the alignment direction of the liquid crystal. The case where the major axis direction of the pixel electrode is oblique corresponds to the case where the alignment direction of the alignment film is oblique.

In addition, the alignment direction of the alignment film and the direction of the long axis direction of the pixel electrode need to be determined depending on the liquid crystal material used. When the dielectric anisotropy of the liquid crystal is positive, the long axis direction of the comb electrode in the pixel electrode is disposed in the orientation direction and the θ degree, for example, 5 ° to 15 °, and the dielectric anisotropy of the liquid crystal Is negative, the major axis direction of the comb-tooth electrode in the pixel electrode is disposed in a direction perpendicular to the alignment direction and in a direction forming θ degrees, for example, 5 degrees to 15 degrees.

FIG. 10 describes the configuration according to the present invention in the case of using liquid crystal with positive dielectric anisotropy. In FIG. 10, the substrate 100 is curved at its end so as to be rolled in the x direction as indicated by the arrow RD. The alignment direction AL of the alignment film 113 is the x direction so as not to cause peeling of the alignment film 113.

The right side of FIG. 10 shows the direction of the pixel electrode 112 in this case. That is, the direction of the comb electrode 1122 of the pixel electrode 112 forms an angle θ with the direction of the alignment axis AL of the alignment film 113. Thus, generation of domains in the liquid crystal layer can be prevented, and peeling of the alignment film 113 when it is curved can be prevented.

FIG. 11 describes the configuration according to the present invention in the case of using liquid crystal with negative dielectric anisotropy. The bending direction of the substrate 100, the alignment axis AL of the alignment film 113, and the like are the same as in FIG. That is, peeling of the alignment film 113 is prevented by setting the direction in which the substrate 100 is curved to a direction in which the strength of the alignment film 113 is strong.

11 is different from FIG. 10 in that the extending direction of the comb electrode 1122 in the pixel electrode 112 is inclined by θ with respect to the direction of 90 degrees with respect to the alignment axis AL of the alignment film 113. This prevents the generation of domains when the dielectric anisotropy is negative. That is, according to the configuration of FIG. 11, in the case where the dielectric anisotropy is negative, the peeling of the alignment film 113 is prevented and the generation of the domain is prevented even if the liquid crystal display device is used by bending. I can do it.

This embodiment is an example where the present invention is applied to a foldable liquid crystal display device. FIG. 12 is a schematic view of a liquid crystal display device which can be folded along the folding line FL. FIG. 12 shows that the right side of the substrate 100 is bent along the bending line FL, and the x-axis direction is changed from X1 to X2. The same is true for the figures shown below. Bending is equivalent to bending a liquid crystal display with a very small radius of curvature. That is, in the vicinity of the bending line, a large stress is generated in the alignment film 113 in the direction perpendicular to the bending line. Therefore, after the light alignment, the alignment axis AL of the alignment film 113 may be perpendicular to the bending line FL so that the strength of the alignment film 113 does not deteriorate in the x direction.

That is, in the configuration of FIG. 12, the polarization axis UVP direction of the polarized ultraviolet light and the orientation axis AL direction of the alignment film 113 are the same as in the case of FIG. In FIG. 12, since the liquid crystal in the case where the dielectric anisotropy is positive is used, the extending direction of the comb teeth of the pixel electrode 112 is a direction inclined by the angle θ with the alignment axis AL.

FIG. 13 is a schematic view in the case of using liquid crystal with negative dielectric anisotropy in a liquid crystal display which can be folded along a folding line FL. 13, the bending axis FL of the substrate 100, the bending direction, the polarization axis UVP of polarized ultraviolet light used for optical alignment, and the alignment direction AL of the alignment film 113 are the same as in FIG.

13 is different from FIG. 12 in that the direction of the comb electrode 1121 of the pixel electrode 112 is inclined by an angle θ with respect to the direction forming 90 degrees with the orientation axis. The reason for this is to prevent the generation of domains in the liquid crystal layer, as described in FIG.

As described above, even in the liquid crystal display device which can be folded, generation of domains can be prevented and peeling of the alignment film 113 can be prevented.

Example 3 shows another configuration in the case of folding the liquid crystal display device in two. FIG. 14 is a schematic view showing one aspect in the third embodiment. The figure on the left side of FIG. 14 is a schematic view of a liquid crystal display device which can be folded along a folding line FL, as in FIG. 12 and the like. The direction of the alignment axis AL of the alignment film 113, the direction of the bending line FL, etc. are the same as in FIG.

14 is different from FIG. 12 in that strong stress is applied to the alignment film 113 and no photo-alignment is performed near the bending line FL. That is, if the alignment film 113 is not subjected to the light alignment process, the strength of the alignment film 113 in that portion does not deteriorate. Therefore, the risk of peeling off the alignment film 113 is further reduced. In FIG. 14, a region in which the alignment film 113 is not subjected to the light alignment has a width w1 including the folding line FL. The width w1 is, for example, the same as the thickness of the liquid crystal display panel.

That is, bending can be considered synonymous with bending with the same radius of curvature as the thickness of the liquid crystal display panel. Therefore, the light alignment process may not be performed on the portion of the width w1 where the stress is concentrated. However, since light from the backlight leaks in a portion where the light alignment processing is not performed, it is necessary to form a black matrix as a light shielding film on the corresponding portion of the counter substrate 200. The extending direction of the comb electrode 1122 of the pixel electrode 112 in FIG. 14 is the same as FIG. 12 when the liquid crystal has a positive dielectric constant, and the same as FIG. 13 when the liquid crystal has a negative dielectric constant. is there.

Another mode in FIG. 14 is to apply weaker light orientation to the area of width w1 including the folding line FL in FIG. 14 than the other areas. If the light alignment is weak, the liquid crystal is not sufficiently aligned and the black level rises. That is, the contrast is reduced. However, since the liquid crystal has viscosity, if the liquid crystal on both sides of the area of width w1 is sufficiently oriented in the right side of FIG. 14, the influence of the liquid crystals on both sides of the area of width w1 of FIG. And may be oriented in the same manner as other regions. Therefore, in some cases, the reduction in contrast can be suppressed without forming a black matrix on the counter substrate 200 or the like.

The feature of the first embodiment of FIG. 14 is that the alignment film 113 is formed on the entire surface of the substrate 100, and the optical alignment processing by the ultraviolet light is not performed on the bent region w1. For this purpose, a mask may be used for the width w1 when performing the light alignment process, and ultraviolet light may not be emitted. On the other hand, the feature of the second embodiment of FIG. 14 is that the alignment film 113 is formed on the entire surface of the substrate 100, and the bent region w1 needs to be subjected to photoalignment treatment with ultraviolet light weaker than other portions. In such a case, it is possible to use a mask that is semitransparent to the polarized ultraviolet light used. Such a mask is used when performing so-called halftone exposure.

FIG. 15 is a schematic view showing another aspect in the third embodiment. The left side of FIG. 15 is a schematic view of the liquid crystal display device which can be folded along the folding line FL. The point in which FIG. 15 differs from FIG. 14 is that the alignment direction of the alignment film 113 is parallel to the bending line, and as described in FIG. 6 etc., the alignment film 113 becomes weak because the polyimide is torn. Direction. That is, when the substrate 100 is bent along the bending line FL, the alignment film is easily peeled off.

In order to cope with this, in FIG. 15, as shown in the right-hand drawing, the folding line FL is included, and for example, the region of the width w1 is not subjected to the light alignment processing. In this portion, the mechanical strength of the alignment film 113 is not reduced unless the light alignment is performed, so the alignment film 113 is not easily peeled off. Since light from the backlight leaks in a portion where the alignment film 113 is not subjected to the alignment process, it is necessary to form a black matrix or the like as a light shielding film on the counter substrate 200 etc. corresponding to this portion.

In the case of bending, as shown by the width w1 of the right side of FIG. 15, the area where the stress is large is limited to about the thickness of the liquid crystal display panel, so the light shielding area may be small. Therefore, the display area is not greatly reduced. From the requirements of the product, it may be necessary to set the alignment direction of the alignment film 113 as shown in FIG. 15. In that case, peeling of the alignment film 113 can be prevented by adopting the configuration of the present invention. It can.

Also in the case of FIG. 15, as in FIG. 14, the alignment film 113 may be formed on the entire surface of the substrate 100, and the photoalignment process may be performed using a mask that does not irradiate the ultraviolet light to the region w1 including the bending line FL. .

The fourth embodiment shows still another configuration in which the liquid crystal display device is folded in half. FIG. 16 is a schematic view showing one aspect in the third embodiment. The drawing on the left side of FIG. 16 is a schematic view of a liquid crystal display device which can be folded along a folding line FL, as in FIG. 14 and the like. The direction of the alignment axis AL of the alignment film 113, the direction of the bending line FL, etc. are the same as in FIG.

The right side of FIG. 16 is a plan view showing the features of this embodiment. In the drawing on the right side of FIG. 16, the alignment film 113 is formed on the entire surface of the substrate 100 except the area of the width w1 including the bending line FL. That is, in the substrate 100, in the region of the width w1, not the alignment film 113 but the capacitance insulating film 111 is exposed. Since the alignment film 113 does not exist in the stressed bending region, the alignment film 113 is not peeled off even when the liquid crystal display device is bent.

The alignment film 113 is often formed by flexographic printing, inkjet, or the like. In the case of flexographic printing, the printing plate may be shaped as shown in FIG. In addition, the application range of the inkjet may be programmed as shown in FIG. On the other hand, in the photo-alignment process using ultraviolet light, since the alignment film 113 does not exist in the bent portion, the alignment film 113 is not deteriorated even when irradiated with ultraviolet light, so the entire surface of the substrate is not used. It is also possible to However, since the ultraviolet light to be photo-aligned is a large energy ultraviolet light having a wavelength of about 250 nm, there is a risk that the overcoat film 203 may be deteriorated if it is on the exposed capacitive insulating film 111 or the counter substrate 200 side. In order to prevent this, the region of width w 1 where the alignment film 113 is not formed may be masked to avoid ultraviolet irradiation.

FIG. 17 is a schematic view showing another aspect in the fourth embodiment. The left side of FIG. 17 is a schematic view of a liquid crystal display device which can be folded along a folding line FL. 17 differs from FIG. 16 in that the alignment direction AL of the alignment film 113 is parallel to the bending line, and as described with FIG. 6 etc., the alignment film 113 is weak because the polyimide is torn. It is the direction in which That is, when the substrate 100 is bent along the bending line FL, the alignment film 113 is easily peeled off.

On the other hand, in FIG. 17, as shown in the right side of the drawing, the folding line FL is included, and for example, the alignment film 113 is not formed in the area of the width w1. If the alignment film 113 does not exist, there is no peeling of the alignment film due to the deterioration of the alignment film 113. The method of forming the alignment film 113 as shown on the right side of FIG. 17 is the same as that described in FIG. The right side of FIG. 16 differs from the right side of FIG. 17 only in the alignment direction of the alignment film 113. Depending on the requirements of the product, the alignment direction of the alignment film 113 may need to be as shown in FIG. 17. In this case, peeling of the alignment film can be prevented by adopting the configuration of the present invention. .

The present embodiment is a case where the liquid crystal display device is folded in four, and the first bending line FL1 and the second bending line FL2 cross each other. If the first folding line FL1 and the second folding line FL2 are parallel even in the case of four-fold, the same configuration as the two-fold in the second to fourth embodiments may be employed.

FIG. 18 is a schematic view showing a first aspect in the fifth embodiment. The left side of FIG. 18 is a perspective view showing a form of four fold. In the left side of FIG. 18, the liquid crystal display device is bent by the first bending line FL1 and the second bending line FL2 as shown by the curved arrows in the drawing. The first bending line FL1 and the second bending line FL2 intersect with each other.

FIG. 18 shows that the right side of the substrate 100 is bent at a bending line FL1, and the x-axis direction changes from X1 to X2. The same is true for the figures shown below. FIG. 18 shows that the lower side of the substrate 100 is bent at a bending line FL2, and the y-axis direction is changed from Y1 to Y2. The same is true for the figures shown below.

In FIG. 18, the alignment films in the four regions divided by the folding lines FL1 and FL2 are all photo-aligned in the x direction, which is the same direction. In this alignment direction, as described with reference to FIG. 7 and the like, peeling of the alignment film 113 is unlikely to occur with respect to the bending line FL1. On the other hand, in this alignment direction, peeling of the alignment film 113 is likely to occur with respect to the bending line FL2.

The figure on the right side of FIG. 18 is a plan view showing the alignment process of the alignment film 113 to cope with this. In the right side of FIG. 18, the alignment film 113 is formed on the entire surface of the substrate 100. In the photo-alignment process, the alignment process is performed such that the alignment axis AL of the alignment film 113 is in the x direction. The feature of FIG. 18 does not perform the light alignment process on the region w1 including the folding line FL2. Therefore, since the strength of the alignment film 113 in this region is not deteriorated, the alignment film 113 is not easily peeled off even if it is bent.

The manufacturing method for realizing such a configuration of FIG. 18, the effects and the like are similar to those described in the third embodiment. Therefore, according to the configuration of FIG. 18, peeling of the alignment film 113 can be suppressed even in the case of four folds. A light shielding film of black matrix or the like is formed on the alignment film 113 in the area of the width w1 which is not subjected to the alignment process as described in the third embodiment.

FIG. 19 is a schematic view showing a second aspect in the fifth embodiment. The left side of FIG. 19 is a perspective view showing the manner of bending of the liquid crystal display device, but is the same as the left side of FIG. That is, in the configuration on the left side of FIG. 19, the alignment film 113 is easily peeled off in the vicinity of the second bending line FL2.

The figure on the right side of FIG. 19 is a plan view showing the features of this embodiment. In the drawing on the right side of FIG. 19, the alignment film 113 is not formed in the region of the width w1 including the second bending line FL2. That is, since the alignment film 113 does not exist in this region, the alignment film 113 is not peeled off. This embodiment is an application of the configuration of the fourth embodiment when the liquid crystal display device is folded in four. The method of forming the alignment film 113, the alignment treatment, and the like are the same as those described in the fourth embodiment. In addition, a light shielding film made of a black matrix or the like is formed in the region of width w1 where the alignment film 113 is not formed, as in the fourth embodiment.

FIG. 20 is a schematic view showing a third aspect in the fifth embodiment. The drawing on the left side of FIG. 20 is a perspective view showing the manner of bending of the liquid crystal display device, and is the same as the drawing on the left side of FIG. The figure on the right side of FIG. 20 is a plan view showing the features of this embodiment. That is, although the alignment film 113 is formed on the entire surface, the optical alignment process is not performed on the region of the width w1 including the bending lines FL1 and FL2. If the optical alignment processing is not performed, the strength of the alignment film does not deteriorate, so peeling of the alignment film 113 does not occur.

The configuration of FIG. 20 can be formed by applying the configuration described in the third embodiment. In addition, a light shielding film made of a black matrix or the like is formed on the alignment film 113 in the region of the width w1 which is not subjected to the alignment processing, as described in the third embodiment.

In the case of FIG. 20, the area to which bending stress is applied is only the area of width w1 including the bending lines FL1 and FL2. Therefore, the alignment direction AL of the alignment film can be applied not only to the x direction shown in FIG. 20 but also to the y direction. That is, the configuration of FIG. 20 can be applied even when the alignment direction of the alignment film is set to the y direction according to the product specification.

FIG. 21 is a schematic view showing a fourth aspect in the fifth embodiment. The left side of FIG. 21 is a perspective view showing the manner of bending of the liquid crystal display device, but is the same as the left side of FIG. The drawing on the right side of FIG. 21 is a plan view showing the features of this aspect. That is, the alignment film 113 is not formed in the region of the width w1 including the folding lines FL1 and FL2. If the alignment film 113 does not exist, the strength of the alignment film does not deteriorate, so peeling of the alignment film 113 does not occur.

The configuration of FIG. 21 can be formed by applying the configuration described in the fourth embodiment. In addition, a light shielding film made of a black matrix or the like is formed in a region of width w1 where the alignment film 113 does not exist, as in the fourth embodiment.

Also in the case of FIG. 21, the area to which bending stress is applied is only the area of width w1 including the bending lines FL1 and FL2. Therefore, the alignment direction of the alignment film 113 can be applied not only to the x direction shown in FIG. 21 but also to the y direction. That is, the configuration of FIG. 21 can be applied even when the alignment direction of the alignment film is set to the y direction according to product specifications.

The present embodiment is another configuration in the case where the liquid crystal display device is folded in four, and in which the first bending line and the second bending line intersect. In the sixth embodiment, even in the case of such four-fold, the alignment process can be performed on the area along the first bending line FL1 and the second bending line FL2 as in the other areas. It is.

The left drawing of FIG. 22 is a perspective view showing a bending mode of the liquid crystal display device, but the bending state is the same as the left drawing of FIG. 18 etc. in the third embodiment. The left side of FIG. 22 is different from the left side of FIG. 18 of the third embodiment in that the mechanical direction of the alignment film 113 is strong, and the alignment direction of the alignment film 113 is the side of the substrate. It is a point that is 45 degrees against. By this, a portion where the strength of the alignment film 113 is weak in the vicinity of the folding lines FL1 and FL2 is eliminated, the alignment film 113 is uniformly formed on the entire surface of the substrate, and four-fold can be made.

The drawing on the upper right side of FIG. 22 is a plan view showing the alignment direction AL of the alignment film 113 in this embodiment. In FIG. 22, the alignment direction AL is inclined by η with respect to a bending line FL2 indicated by a dotted line. The central value of η is 45 degrees. The range of η is preferably 45 ° ± 1 ° but acceptable up to 45 ° ± 10 °.

The lower right part of FIG. 22 shows the shape of the pixel electrode 112 when liquid crystal is used when the dielectric anisotropy is positive. In FIG. 22, the extending direction of the comb electrode 1121 of the pixel electrode 112 is shifted by θ with respect to the alignment direction AL of the alignment film 113. The value of θ is 5 degrees to 15 degrees. This is to prevent the generation of domains in the liquid crystal layer as described in the first embodiment and the like.

FIG. 23 is a diagram showing a configuration in the case where a liquid crystal display device is folded in four when liquid crystal having a negative dielectric anisotropy is used. The left side of FIG. 23 is the same as the left side of FIG. Also, the upper right drawing of FIG. 23 is the same as the upper right drawing of FIG. That is, the alignment direction AL of the alignment film 113 when the liquid crystal display device is folded along the folding lines FL1 and FL2 is at an angle of η with respect to the folding line FL2.

The lower right part of FIG. 23 shows the shape of the pixel electrode 112 corresponding to the liquid crystal with negative dielectric anisotropy. The extending direction of the comb-tooth electrode 1121 of the pixel electrode 112 is shifted by θ from the direction of 90 degrees with respect to the alignment direction AL. The value of θ is 5 degrees to 15 degrees. This is to prevent the generation of domains in the liquid crystal layer as described in the first embodiment and the like.

As described above, in the configuration of the sixth embodiment, even when the liquid crystal display device is folded in four, the alignment film 113 is not subjected to the light alignment treatment for a predetermined width along the folding line, for example w1. There is no need to adopt a configuration in which the alignment film 113 is not formed. Therefore, the alignment film 113 can be uniformly applied to the substrate 100 and the light alignment process can be uniformly performed. The formation of a light shielding film by a black matrix or the like corresponding to this is also unnecessary. However, the strength of the alignment film along the first bending line FL1 and the second bending line Fl2 is an intermediate value between the direction in which the strength of the alignment film is weak and the direction in which the strength of the alignment film is strong.

The above description is mainly made on the alignment film 113 formed on the TFT substrate 100 side, but the same applies to the alignment film 113 formed on the counter substrate 200 side. However, the base film of the alignment film 113 formed on the opposite substrate 200 side is an overcoat film 203 as shown in FIG. Further, the alignment directions AL of the alignment film 113 on the TFT substrate 100 side and the alignment film 113 on the counter substrate side are the same.

In the above description, the IPS type liquid crystal display device is described as having the pixel electrode 112 formed on the upper side of the common electrode 110, but in the present invention, the common electrode 110 having a slit is formed on the pixel electrode 112. The invention can also be applied to a liquid crystal display device of the IPS type in the case of In this case, the direction in which the comb electrode 1121 of the pixel electrode 112 extends may be replaced with the slit in the common electrode 110 as the extending direction.

11 scanning line 12 video signal line 13 pixel 20 liquid crystal display panel 30 display area 40 terminal area 100 TFT substrate 101 first undercoating film 102 second undercoating film 103: semiconductor layer, 104: gate insulating film, 105: gate electrode, 106: interlayer insulating film, 107: contact electrode, 108: inorganic passivation film, 109: organic passivation film, 110: common electrode, 111: capacitance insulating film, 112: pixel electrode, 113: alignment film, 120: first through hole, 130: second through hole, 140: third through hole, 200: opposing substrate, 201: color filter, 202: black matrix, 203: overcoat Film, 300: liquid crystal layer, 301: liquid crystal molecule, 500: flexible wiring substrate, 1121 Slit,
1122 ... comb electrodes, AL ... orientation, D ... drain unit, S ... source unit, FL ... folding lines, LDD ... Light Doped Drain, PI ... polyimide,
UVP: Polarization axis of polarized UV, RD: Roll direction

Claims

A first photoalignment film is formed on a first substrate, a second photoalignment film is formed on a second substrate, a liquid crystal is sandwiched between the first substrate and the second substrate, 1. A liquid crystal display device which can be bent or bent with the direction 1 as a bending axis or bending axis,
The direction of the alignment axis of the first photo alignment film and the second photo alignment film coincides with the first direction within a range of 90 ° ± 10 °.
The liquid crystal according to claim 1, wherein the direction of the alignment axis of the first photo alignment film and the direction of the alignment axis of the second photo alignment film coincide with the first direction within a range of 90 ° ± 1 °. Display device.
The liquid crystal display device is a liquid crystal display device having a common electrode opposed to a pixel electrode having a comb electrode and an insulating film, and the liquid crystal has positive dielectric anisotropy.
2. The liquid crystal display device according to claim 1, wherein the extending direction of the comb electrode of the pixel electrode and the alignment direction of the first light alignment film are deviated by 5 degrees to 10 degrees.
The liquid crystal display device is a liquid crystal display device having a common electrode opposed to a pixel electrode having a comb electrode and an insulating film, and the liquid crystal has negative dielectric anisotropy.
2. The liquid crystal display device according to claim 1, wherein the direction perpendicular to the extending direction of the comb electrode of the pixel electrode and the alignment direction of the first light alignment film are deviated by 5 degrees to 10 degrees. .
The liquid crystal display device according to claim 1, wherein the first photo alignment film and the second photo alignment film are polyimides having a cyclobutane ring.
The first photo alignment film is formed on the entire display area and has an alignment axis in the same direction, and the second photo alignment film is formed on the entire display area and has an alignment axis in the same direction. The liquid crystal display device according to claim 1, characterized in that:
7. The liquid crystal display device according to claim 6, wherein the direction of the alignment axis of the first photo alignment film coincides with the direction of the alignment axis of the second photo alignment film.
A method of manufacturing a liquid crystal display device, in which liquid crystal is held between a first substrate and a second substrate, and can be bent or bent in a second direction with the first direction as a bending axis or a bending axis. ,
A first alignment film is formed on the first substrate, and the first alignment film is photoaligned using polarized ultraviolet light so as to have an alignment axis in the second direction,
A liquid crystal display characterized in that a second alignment film is formed on the second substrate, and the second alignment film is photo-aligned using polarized ultraviolet light so as to have an alignment axis in the second direction. Device manufacturing method.
Photoalignment is performed using polarized ultraviolet light so that the alignment axis of the first alignment film coincides with the second direction within the range of 0 ° ± 10 °.
9. The liquid crystal display according to claim 8, wherein the photoalignment is performed using polarized ultraviolet light so that the alignment axis of the second alignment film coincides with the second direction in the range of 0 ° ± 10 °. Device manufacturing method.
Photoalignment is performed using polarized ultraviolet light so that the alignment axis of the first alignment film coincides with the second direction within the range of 0 ° ± 1 °.
9. The liquid crystal display according to claim 8, wherein the photoalignment is performed using polarized ultraviolet light so that the alignment axis of the second alignment film coincides with the second direction in the range of 0 ° ± 1 °. Device manufacturing method.
9. The method of manufacturing a liquid crystal display device according to claim 8, wherein the photoalignment is performed using polarized ultraviolet light so that the alignment axis of the first alignment film and the alignment axis of the second alignment film coincide with each other.
9. The method for manufacturing a liquid crystal display device according to claim 8, wherein an alignment film is formed over the entire display area, and the alignment axis is in the same direction over the entire display area.
A liquid crystal display device in which liquid crystal is held between a first substrate and a second substrate and which can be bent with a first direction as a first bending axis,
The first substrate and the second substrate have an alignment film, and in the first substrate and the second substrate, a first region having a first width including the first bending axis. The alignment ability for the liquid crystal is smaller than the alignment ability for the liquid crystal other than the first region,
A liquid crystal display device characterized in that the alignment film is subjected to alignment treatment with polarized ultraviolet light in portions other than the first region.
14. The liquid crystal display device according to claim 13, wherein the alignment film does not exist in the first region.
The liquid crystal display device according to claim 13, wherein the alignment film is present in the first region, and the alignment film in the first region is not subjected to alignment treatment with polarized ultraviolet light.
The alignment film is present in the first region, and the alignment film in the first region is subjected to alignment treatment with polarized ultraviolet light,
14. The liquid crystal display device according to claim 13, wherein the alignment ability of the alignment film in the first region is smaller than that in the alignment film other than the first region.
The liquid crystal display may be further bent with a second direction as a second bending axis, and the first bending axis and the second bending axis intersect with each other.
The alignment ability for liquid crystal molecules in a second region having a second width including the second bending axis is smaller than the alignment ability for liquid crystal molecules in a region excluding the first region and the second region,
14. The liquid crystal display device according to claim 13, wherein the alignment film is subjected to alignment treatment with polarized ultraviolet light in portions other than the first region and the second region.
The liquid crystal display device according to claim 17, wherein the alignment film is not present in the first region and the second region.
The alignment film is present in the first region and the second region, and the alignment film in the first region and the second region is not subjected to an alignment treatment with polarized ultraviolet light. The liquid crystal display device according to claim 17.
The alignment film is present in the first region and the second region, and the alignment film in the first region and the second region is subjected to an alignment treatment with polarized ultraviolet light,
The alignment capability of the alignment film of the first region and the second region is smaller than that of the alignment film of the region excluding the first region and the second region. Item 18. A liquid crystal display device according to item 17.