JP2001083529A - Liquid crystal display device and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal display device of high picture quality with a high throughput, to suppress disturbance in the alignment due to flowing of a liquid crystal during injected when a method of aligning by light is used, and to prevent the contamination of a liquid crystal layer by a sealing material. SOLUTION: In the liquid crystal display device having a liquid crystal layer LC held between a pair of substrates SUB1, SUB2, a columnar spacer PSP to control the gap between the first and second substrates is formed on the first substrate SUB1. A bank-like projection WB is formed on the second substrate SUB2 in the periphery of the effective display region of the substrate. A sealing part SL1 to laminate the first and second substrates SUB1, SUB2 are formed in such a manner that the cross-sectional structure near the sealing part includes the liquid crystal LC, bank-like projection WB formed on the substrate, and the sealing part SL1 arranged in this order. The liquid crystal layer LC is disposed on the substrate by printing, coating or dropping.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device and a method of manufacturing the same, and more particularly, to a high contrast liquid crystal display device and a method of manufacturing the same with high throughput.

[0002]

2. Description of the Related Art Display of a liquid crystal display device is performed by changing the alignment direction of liquid crystal molecules by applying an electric field to a liquid crystal layer sandwiched between a pair of substrates, and thereby causing a change in optical characteristics of the liquid crystal layer. Will be

In a conventional liquid crystal display device, a twisted nematic (T.sub.T) which performs display using the optical rotation of liquid crystal is used.
N) As typified by a display method or a super twisted nematic (STN) display method in which display is performed using birefringence of liquid crystal, electrodes are provided on a pair of substrates, and the direction of an electric field applied to the liquid crystal is changed. The direction was set substantially perpendicular to the substrate surface. In these liquid crystal display devices, a pair of substrates provided with stripe-shaped electrodes, which is called a simple matrix system, is arranged so that the electrodes are substantially orthogonal to each other.
A method of driving a liquid crystal by applying an electric field vertically to a substrate, and a method called an active matrix method, in which a thin film transistor (TFT) element is formed in each pixel and an electric field is applied to the liquid crystal for each pixel, has been used. On the other hand, a method of performing a display using a birefringent property of a liquid crystal by using a comb-shaped electrode to make the direction of an electric field applied to the liquid crystal substantially parallel to the substrate (lateral electric field method) is, for example, a special method. It is proposed in JP-B-63-21907 and JP-A-5-505247. The horizontal electric field method has an advantage of a wider viewing angle than the conventional TN method, and is a promising technology as an active matrix liquid crystal display device.

In the method of manufacturing a liquid crystal display device, first, an electrode or an alignment film is formed on a substrate, and the alignment film is provided with a liquid crystal alignment ability. Then, spherical beads called spacers are scattered on the substrate. A pair of substrates are attached to each other with a sealant. The material of the spherical spacer is a resin or an inorganic material, for example, silicon oxide. A method of arranging spacers in a non-pixel region for high contrast is disclosed in, for example, Japanese Patent Application Laid-Open Nos. 10-170728, 9-61828, 6-250194, and 5-53121. , JP 5
JP-173147, JP-A-8-160433, JP-A-8-2
No. 92426 and Japanese Patent Application Laid-Open No. 7-325298. Further, instead of spherical beads, a columnar spacer is formed on a substrate in advance, and the distance between the substrates is controlled by the spacer. For example, Japanese Patent Application Laid-Open Nos. 6-194615 and 9-1200 disclose a method.
No. 72, JP-A-9-120075, JP-A-9-127525, JP-A-10-153797, JP-A-10-186340, and JP-A-10-268317. As a sealing material, there is a material using a thermosetting resin or a photocurable resin.

As the alignment film, a polymer film is mainly used, and among them, a polyimide resin having excellent heat resistance is widely used. As a method for imparting liquid crystal alignment ability to the alignment film, a method called a rubbing method, in which the alignment film is rubbed in one direction with a cloth or the like, is widely used. Further, a method of imparting liquid crystal alignment ability by light irradiation (photo alignment method) is described in, for example, JP-A-2-277025, JP-A-4-220402,
It is proposed in JP-A-6-287453 and JP-A-7-138308. In addition, a method called a shearing method for aligning a liquid crystal while rubbing the substrate has also been proposed (The 23rd Liquid Crystal Symposium Proceedings, p. 238 (1997).
Proceedings of 1998 Liquid Crystal Society of Japan Discussion Meeting, 60
P. (1998)).

[0006] As a method of injecting liquid crystal between the substrates, a pair of substrates bonded with a sealing resin is used.
In general, the pressure is reduced from the opening provided in the seal portion, the liquid crystal is brought into close contact with the opening, the external pressure is increased, and the injection is performed by utilizing the pressure difference between the inside and outside of the pair of bonded substrates. As another method, a method has been proposed in which a liquid crystal is dropped on a substrate in advance and then the substrate is bonded together in order to shorten the liquid crystal injection time and improve the production throughput (Japanese Patent Application Laid-Open No. 9-311340). Furthermore, a method of providing a plurality of openings in the seal portion, sucking and depressurizing the inside of the substrate from one opening, and injecting liquid crystal from the other (Japanese Patent Laid-Open No. 8-262461), attaching an injection / exhaust nozzle to the opening, A method of injecting liquid crystal from the nozzle after reducing the pressure in the cell (Japanese Patent Laid-Open No. 10-253975) has been proposed.

[0007]

When the above-mentioned spherical spacers were scattered on a substrate to fabricate a liquid crystal display device, unevenness in display and contrast were observed due to the denseness of the spherical spacers and light leakage from around the spacers during black display. Decreased. In particular, the transmittance of the liquid crystal panel increases as the voltage applied to the liquid crystal layer is changed from a low voltage to a high voltage. The so-called normally black (closed) type liquid crystal display device, for example, the above-described STN type or horizontal electric field type liquid crystal In the display device,
The contrast was significantly reduced due to light leakage from around the spacer.

The liquid crystal alignment control method based on the photo alignment method described above is an effective method for suppressing the generation of dust and static electricity, which are problems in the rubbing method, and for improving the production yield. However, when a liquid crystal display device was actually manufactured using this photo-alignment method, flow-like unevenness occurred along the direction in which the liquid crystal flows when the liquid crystal was injected. Upon detailed examination, it was observed that the liquid crystal was oriented in a direction different from the desired liquid crystal orientation direction.

Further, a method of dropping liquid crystal on a substrate in advance and then bonding the substrate is a method that is effective for high throughput because the time required for the liquid crystal injection step is greatly reduced. However, this method has a problem that the liquid crystal is contaminated because the liquid crystal contacts the uncured sealing material. In particular, in the active matrix type liquid crystal display device, there is a problem that the voltage holding ratio is reduced due to the contamination and the display quality is reduced. Further, in this method, it was difficult to control the amount of liquid crystal dropped between the substrates. further,
Depending on the type of sealing material used to attach the substrates,
Even after curing, there is a problem that the liquid crystal is contaminated and the display quality is deteriorated. Accordingly, an object of the present invention is to solve the above problems and to provide a high-contrast, high-quality liquid crystal display device by a high-throughput manufacturing method.

[0010]

In order to achieve the above object, the present invention uses the following means.

In a liquid crystal display device according to a first embodiment of the present invention, at least one of the first and second substrates is transparent, a liquid crystal layer disposed between the first and second substrates, and the first and second substrates. In a liquid crystal display device including a seal portion for bonding a second substrate and an electrode group for applying a voltage to liquid crystals formed on the first and second substrates, a liquid crystal display device includes a seal portion on the first substrate. A columnar spacer for controlling the distance between the first and second substrates, a projection on the second substrate at the periphery of the effective display area of the substrate, and a sealing portion formed in a cross-sectional structure around the sealing portion; The arrangement is a liquid crystal, a vertical protrusion formed on the substrate,
It is arranged in the order of the seal portion.

According to another embodiment of the present invention, at least one of the first and second substrates is transparent, the liquid crystal layer disposed between the first and second substrates, and the first and second substrates. A seal portion for bonding the two substrates, an electrode group formed on one of the first and second substrates to apply an electric field substantially parallel to the substrate surface to the liquid crystal layer,
A liquid crystal display device comprising a pair of polarizing plates disposed with a liquid crystal layer interposed therebetween, comprising: a first substrate; a columnar spacer for controlling a distance between the first and second substrates; It is stated that the projection is provided on the periphery of the effective display area of the substrate, and the seal portion is arranged in the peripheral sectional structure in the order of the liquid crystal, the projection formed on the substrate, and the seal portion. Things.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the drawings. As shown in FIGS. 1 and 2, in the present invention, first, first
In a liquid crystal display device in which a liquid crystal layer is sandwiched between a pair of substrates, an electrode PE, first and second electrodes are provided on a first substrate SUB1.
Columnar spacers PPSP for controlling the distance between the substrates,
An alignment film AL is provided, and an electrode PE is formed on the second substrate SUB2.
Provided on the periphery of the effective display area DA of the substrate are protrusions WB and an alignment film AL, and a seal portion SL1 for bonding the first and second substrates is formed in a peripheral cross-sectional structure (FIG. 3). The liquid crystal layer LC, the projection WB formed on the substrate, and the seal portion SL1 are arranged in this order.
The effective display area DA is a general term for a portion used for display in which pixels are configured. In the seal part SL1,
A spherical spacer or a glass fiber having a size corresponding to the distance between the substrates may be contained. As long as the protrusion WB has an adhesive property to the substrate, the protrusion WB and the seal portion SL1 may be used. In the present invention, the second projection WB is provided on the periphery of the effective display area DA on the substrate.
Even if the liquid crystal layer LC is arranged on the substrate SUB2 by printing, coating, and dropping, the liquid crystal layer LC is blocked by the projections WB,
There is no leakage around the substrate. Moreover, there is no contact between the liquid crystal and the uncured sealing material, and there is no contamination of the liquid crystal. Therefore, the time required for disposing the liquid crystal between the substrates can be significantly reduced as compared with the conventional liquid crystal injection method. Answer In addition to the conventional method,
Even in a method in which liquid crystal is injected between the substrates after the substrates are bonded to each other and the sealing material is cured, the liquid crystal does not come into contact with the cured sealing material, so that there is no liquid crystal contamination from the sealing material. In the conventional method of dispersing spherical spacers on a substrate,
In some cases, spherical beads are arranged on the convex protrusions WB, and there is a problem in that the substrate interval around the convex protrusions WB and the substrate interval in the central portion of the display area are different, resulting in display unevenness. However, since the columnar spacers PSP are used in the method of the present invention, there is no problem of unevenness in substrate spacing.
In the present invention, after the liquid crystal layer LC is disposed on the second substrate SUB2, the first substrate SUB1 and the second substrate SUB2 are attached to each other, so that the liquid crystal layer is sandwiched between the substrates and the sealing material is cured. Thus, a liquid crystal panel can be completed. In this case, after sandwiching the liquid crystal between the substrates, the sealing material, which is the material of the sealing portion SL1, is cured. Therefore, in the case of a thermosetting sealing material, when the liquid crystal is maintained at a high temperature, the deterioration of the liquid crystal proceeds. Therefore, at a relatively low temperature, a temperature at least 20 to 30 degrees higher than the liquid crystal phase-isotropic phase transition temperature of the liquid crystal layer. A material that cures is desirable.

In the method of the present invention, when the substrates are bonded together, the liquid crystal is displaced by the volume of the columnar spacer, and bubbles can be prevented from entering between the substrates. In the present invention, the opening AP through which the surplus liquid crystal that has been displaced is discharged is provided in the round protrusion. The liquid crystal discharge portion AP is sealed with a sealant SL2 after bonding the substrates. Further, it is desirable that the liquid crystal discharge portion is located in a portion where there is no peripheral driving circuit (FIGS. 4 to 8). 4 and 6 show the configuration of an STN display type liquid crystal display device, in which an opening A is provided at a long side portion or a short side portion where terminals for connecting peripheral circuits are not exposed.
P is provided. FIG. 5, FIG. 6, and FIG. 7 show a configuration of a TFT type liquid crystal display device using a TN mode or a lateral electric field mode.
5 and 7, an opening AP is provided at a short side or a long side where no terminal is exposed. In FIG. 8, terminals for connecting peripheral circuits are exposed on all four sides, and the openings AP are formed at corners of the substrate so as to avoid the terminals. According to the present invention, the time for injecting liquid crystal can be greatly reduced, and a liquid crystal display device can be manufactured with high yield and high throughput. In the case of using a conventional method of injecting liquid crystal between the substrates after bonding the substrates and curing the sealing material, the opening AP may be used as a liquid crystal injection port.

Further, in the present invention, the sealing material is a photocurable resin. By using a photo-curable resin for the sealant, it is possible to manufacture with higher throughput and higher yield. Further, as described above, in the conventional method, there is a problem that the liquid crystal is contaminated due to the contact between the uncured or cured sealing material and the liquid crystal material, but in the present invention, the back projection WB is uncured or cured. There is no problem because the contact between the sealing material and the liquid crystal is prevented. In this case, since the sealing material is cured by light transmitted through the glass substrate, it is preferable that the light-curing resin be cured by light in the non-light-absorbing wavelength region of the substrate, and more preferably a visible-light curable resin. In the step of curing the sealant by light irradiation, it is desirable to shield the display unit from light.

According to the present invention, the black matrix B for shielding the boundary between the color filters CF and the color filters is provided on the first substrate SUB1 on which the columnar spacers PSP are formed.
M is formed, and the columnar spacer PSP is formed on the black matrix BM (FIG. 9). FIG.
Is a schematic view of the liquid crystal panel of the present invention, in which a columnar spacer P is provided on a black matrix BM arranged around the pixel area PX.
This indicates that the SP is located. In the periphery of the spacer, the alignment of the liquid crystal is not uniform, and the alignment direction of the liquid crystal molecules is different from the alignment control direction by the alignment film. Accordingly, light leakage occurs around the spacer as described above, and the contrast is reduced. In the present invention, the spacer is a columnar spacer, and the black matrix B
Since it is formed on M, it is possible to suppress a decrease in contrast due to light leakage around the spacer. Of course, the columnar spacer may be formed on the substrate opposite to the substrate on which the color filter CF is formed (FIG. 11). However, if the columnar spacer is formed on the color filter substrate in advance, the alignment accuracy of the substrate is less strict. Higher yield. Further, in the present invention, the flattening film OC is formed on the color filter CF and the black matrix BM, and the material of the columnar spacer PSP is the same as the material of the flattening film OC. By using the same material for the planarizing film OC and the columnar spacer PSP and forming them at the same time (FIG. 12), the manufacturing process can be significantly reduced. Examples of the flattening film include cardo polymer, epoxy resin, methacrylate resin, and novolak resin.

Further, in the present invention, the alignment film AL is a polymer film capable of imparting liquid crystal alignment ability by light irradiation. As described above, the method of imparting liquid crystal alignment ability by light irradiation, the so-called light alignment method, is compared with the conventional rubbing method,
Since the generation of dust and static electricity is small, and uniform alignment ability can be imparted even in a portion having a step structure, a high-quality liquid crystal display device can be manufactured with high throughput and high yield. . Moreover, since the columnar spacers and the ridge-shaped projections at the periphery of the substrate are formed on the substrate used in the liquid crystal display device of the present invention, there are many steps, and it is difficult to rub the shadows of the steps by the ordinary rubbing method. Yes,
The photo-alignment method is particularly effective. However, as described above, in the photo-alignment method, in the conventional liquid crystal injection method in which the liquid crystal is injected between the substrates from the opening provided in the seal portion, a flow-like unevenness accompanying the liquid crystal injection occurs, and the display quality is significantly reduced.
In the present invention, since the projections are provided on the periphery of the effective display area DA of the substrate, the liquid crystal can be arranged on the substrate by printing. A liquid crystal display device is obtained. Examples of the polymer film used for the photo-alignment method include a photodegradable polymer film and a site that undergoes cis-trans isomerization by light such as azobenzene or stilbene on the main chain or side chain in the molecular skeleton. A polymer film having a site that undergoes a dimerization reaction, such as cinnamic acid or chalcone, is desirable.
Further, from the viewpoint of heat resistance, a polymer film having polyimide as a basic skeleton is more preferable.

Further, in the present invention, the alignment direction LCDR of the long axis of the liquid crystal molecules on the substrate SUB2 on which the convex protrusions WB are provided.
Are parallel to any one side of the substrate. In this case, when the liquid crystal is printed on the substrate, the roll rotation directions RDR1 and RDR1 are set.
The traveling direction RDR2 of the substrate or roll and the alignment direction LCDR of the liquid crystal molecules are substantially parallel (FIG. 13), and the flow-like unevenness due to the alignment disturbance in the optical alignment film can be further reduced.

Second, in the present invention, a liquid crystal layer is sandwiched between a pair of substrates, and a pair of polarizing plates PL are arranged so as to sandwich the liquid crystal layer. An electric field substantially parallel to the substrate surface is applied to the liquid crystal layer. Electric field type liquid crystal display device in which an electrode group for forming the first substrate S is formed on one of the substrates.
A columnar spacer PSP and an alignment film AL for controlling the distance between the first and second substrates are provided on UB1, and a protrusion WB is formed on the second substrate SUB2 at the periphery of the effective display area DA of the substrate. An alignment film AL is provided, and a seal portion SL1 for bonding the first and second substrates is disposed in a peripheral cross-sectional structure such that a liquid crystal is formed on the substrate, and the protrusion WB is formed on the substrate. The parts SL1 are arranged in this order (FIG. 1
4). As described above, the in-plane switching mode liquid crystal display device has a feature that the viewing angle is wider than that of the conventional TN mode liquid crystal display device.

The operation principle of the horizontal electric field method will be described with reference to an example shown in FIG. FIGS. 15A and 15B are views showing the operation of the liquid crystal in the liquid crystal panel of the horizontal electric field type, wherein FIGS. 15A and 15B are side sectional views, and FIGS. 15C and 15D are plan views. Note that in the whole display element, a plurality of pixels are formed by forming striped electrodes in a matrix, but FIG. 15 shows a portion of one pixel. FIG. 16 shows the angle Φ _p formed by the polarizing plate transmission axis direction PLT and the angle Φ formed by the alignment direction LCDR of the long axis (optical axis) of the liquid crystal molecules near the substrate interface with respect to the direction of the electric field EF.
_Shows the definition of _LC .

FIG. 15A shows liquid crystal molecules L when no voltage is applied.
FIG. 15C is a plan view showing the state of the CM at that time.
Striped electrodes CEL, PEL and SEL are formed inside a pair of transparent substrates SUB and SUB ', and an alignment control film AL is formed thereon. The liquid crystal layer LC is sandwiched between the two substrates. This liquid crystal layer is an aggregate of liquid crystal molecules LCM. Liquid crystal molecules LCM is 45 degrees ≦ is when no electric field is applied | [Phi _LC | As will be <90 °, are oriented in the alignment direction LCDR indicated by an arrow with the alignment layer AL. Note that the dielectric anisotropy of the liquid crystal is assumed to be positive. The reason that Φ _LC is not 90 degrees is to define the direction in which the liquid crystal molecules LCM move relative to the electric field in one direction. That is, in FIG. 15, the liquid crystal molecules LCM are set so as to always move in the direction from the common electrode CEL to the pixel electrode PEL with respect to the electric field direction EF. If Φ _LC = 90 degrees, the liquid crystal molecules LCM move in both the left and right (clockwise) directions in the figure, resulting in the occurrence of domains and display failure.

Next, as shown in FIGS. 15B and 15D,
When an electric field EF is applied to the electrodes CEL and PEL, the liquid crystal molecules LCM change their directions clockwise. At this time, the liquid crystal layer L
The optical properties of the present liquid crystal element change due to the refractive index anisotropy of C and the action of the polarizing plate PL, and display is performed by this change.

Although the case where the liquid crystal layer LC in FIG. 15 has a positive dielectric anisotropy has been described, the liquid crystal layer LC may have a negative dielectric anisotropy. In that case, the initial alignment state is set at 0 degree ≦ | Φ _LC | <4 from the vertical direction of the stripe-shaped electrode.
It is good to be oriented at 5 degrees.

Further, in the present invention, the sealing material SL1 is a photocurable resin. Thus, it is possible to manufacture with higher throughput and higher yield.

In the present invention, a black matrix BM for shielding the boundary between the color filters CF and the color filters is formed on the substrate on which the columnar spacers PSP are formed.
M. In the case of this liquid crystal display device, on the first substrate SUB1, an electrode group PE and a projection WB are formed.
The color filter CF, the black matrix BM, and the columnar spacer PSP may be formed on the second substrate SUB2 (FIG. 17), or the electrode group PE and the columnar spacer PSP may be formed on the first substrate SUB1 by using the second substrate SUB2. The color filter CF, the black matrix BM, and the projection WB on SUB2
(FIG. 18). Also, color filter C
F may be formed on the substrate on which the electrode group PE is formed,
In this case, a columnar spacer PSP may be provided on the color filter CF + electrode substrate SUB1 side, and a projection WB may be provided on the periphery of the counter substrate SUB2 (FIG. 19), or may be provided on the periphery of the color filter CF + electrode substrate SUB2. T-shaped protrusion W
B, and a columnar spacer PSP may be provided on the counter substrate SUB1 side (FIG. 20).

Further, in the liquid crystal display device of the present invention, the parameter d · Δn when the refractive index anisotropy Δn and the thickness of the liquid crystal layer LC is d is set to 0.2 μm <d · Δn <0.4 μm. Have been. In a birefringence mode display method such as a horizontal electric field method, the transmitted light intensity observed with a liquid crystal interposed between polarizing plates whose polarization axes are orthogonal to each other is proportional to sin (πd (Δn / λ). Here, λ is the wavelength of light. In order to maximize the transmitted light intensity, d · Δn should be λ / 2, 3λ / 2, 5λ /
However, in order to obtain white transmitted light while suppressing the wavelength dependence of the transmitted light, λ / 2 is desirably set. That is, considering light of 550 nm having high visibility, d ·
Δn = 0.275 μm. This d · Δn may be practically at least in the range of 0.2 μm to 0.4 μm.

Further, in the liquid crystal display device of the present invention, the polarization axes SPDR of the pair of polarizing plates SP are substantially orthogonal to each other, and the alignment control of the liquid crystal molecules LCM at two interfaces between the liquid crystal layer and the pair of substrates. Direction LCMDR1, LC
MDR2 is substantially parallel, and the polarization axis PL of one polarizing plate
It is characterized in that the DR and the alignment control direction LCCMDR of the liquid crystal molecules substantially match. FIG. 21 shows the arrangement. With this arrangement, a so-called normally black display device is provided in which black display is performed at low voltage and white display is performed at high voltage, that is, luminance increases with an increase in voltage.
With this arrangement, the brightness of black display is lower,
Therefore, a high-contrast liquid crystal display device can be obtained. However, on the other hand, when the spacer exists in the pixel region, the black luminance increases and the contrast decreases due to light leakage from around the spacer. Columnar spacer PS
By arranging P on the black matrix BM, it is possible to suppress a decrease in contrast due to this light leakage, and it is possible to realize a higher contrast. Further, in the present invention, the flattening film OC is formed on the color filter CF and the black matrix BM, and the material of the columnar spacer PSP is the same as the material of the flattening film OC (FIG. 22).

Further, in the present invention, the alignment film AL is a polymer film capable of imparting liquid crystal alignment ability by light irradiation. This caused problems with the conventional rubbing method,
The problem of dust generation and static electricity can be avoided.

Further, according to the present invention, in the in-plane switching mode liquid crystal display device, the alignment direction LCCMDR of the long axis of the liquid crystal molecules on the substrate SUB2 provided with the ridges WB is substantially parallel to any one side of the substrate. There is a feature. This is because the orientation of the liquid crystal molecules can be made parallel to the side of the substrate by making the interdigital electrode for applying an electric field to the liquid crystal layer non-parallel to the side of the substrate. For example, by making the interdigital electrode for applying an electric field to the liquid crystal a “C” shape, the initial alignment direction LCCMDR of the liquid crystal molecules is parallel to either side of the substrate (FIG. 23).

The present invention is effective for STN mode, TN-TFT mode, and horizontal electric field mode liquid crystal display devices. In addition, a low-temperature polysilicon TFT with peripheral circuits formed on a substrate
In the liquid crystal display device, the peripheral circuit part may be particularly thicker than the display area, which is particularly effective.

Hereinafter, embodiments of the present invention will be described specifically.

[Embodiment 1] First, an example in which the liquid crystal display device of the present invention is applied to an STN type liquid crystal display device will be described.

First, an ITO (Indium Tin Oxide) electrode patterned in a stripe pattern was formed on the first substrate SUB1. An acrylate-based photosensitive resin is further applied on the substrate, and ITO is applied by photolithography.
A columnar spacer PSP having a height of about 5.4 μm was formed between the electrodes. Further, a polyimide precursor varnish was applied thereon and baked to form a polyimide alignment film AL on the substrate. Next, red, green, and blue color filters CF were formed on the second glass substrate SUB2, and a black matrix BM was formed so as to surround each pixel region PX. Next, a flattening film OC was formed on the substrate on which the CF and BM were formed. Furthermore, an ITO electrode patterned in a stripe shape was formed thereon. Thereafter, a photosensitive resin was applied on the substrate, and a throat-like projection WB having a height of about 5 μm and a width of about 0.5 mm was formed on the periphery of the effective display area DA of the substrate by photolithography. Further, a polyimide precursor varnish was applied thereon and baked to form a polyimide alignment film AL on the substrate. Next, a rubbing process was performed on the alignment film AL for both the first and second substrates. After rubbing, the second substrate SUB
An appropriate amount of liquid crystal LC was dropped on 2 and a photo-curable sealing material SL1 was applied to the outside of the ridge WB as viewed from the display area DA. At this time, the liquid crystal LC was interrupted due to the projections WB, and the liquid crystal LC was not in contact with the sealing material SL1. Next, the substrates were bonded so that the ITO of the upper and lower substrates was perpendicular to each other and the angle between the rubbing directions RDR of the upper and lower substrates was 60 degrees (the twist angle of the liquid crystal was 240 degrees). At this time, the columnar spacers PSP of the first substrate SUB1 were arranged on the BM on the second substrate SUB2. At this time, the columnar spacer PSP is connected to the IT of the substrates SUB1 and SUB2.
It is arranged in the O electrode gap. Next, light was applied only to the seal portion to cure the seal material. A polarizing plate PL and a retardation plate RF were attached to this liquid crystal element (FIGS. 24 and 25).
At this time, P is set so that the transmittance of the liquid crystal panel increases with an increase in voltage, that is, a so-called normally black mode.
L and RF were arranged. Further, a driving circuit DC for giving an electric signal to the liquid crystal is attached to the periphery, a light source is installed, and the STN
Completed as a liquid crystal display device.

In the manufactured STN type liquid crystal display device, the time for injecting liquid crystal in the manufacturing process could be greatly reduced.
By arranging the columnar spacers PSP on the BM, light leakage around the spacers could be suppressed, and high contrast of about 80: 1 was obtained, without deterioration in image quality due to non-uniform cell gap.

Embodiment 2 Next, an example in which the liquid crystal display device of the present invention is applied to a TN-TFT type liquid crystal display device will be described.

First, an ITO electrode and a TFT element as an active element are formed on a first substrate SUB1, and a photolithography method using a photosensitive resin is applied to a periphery of an effective display area DA of the substrate at a height of about 5 μm. About 0.5mm in width
Throat-like projections WB were formed. Further, a polyimide precursor varnish is applied thereon and baked to obtain a polyimide alignment film AL.
Was formed on the substrate. Next, red, green, and blue color filters CF are formed on the second glass substrate SUB2, and the black matrix BM surrounds each one pixel region PX.
Was formed. Next, an ITO electrode was formed on the substrate on which the CF and BM were formed. Thereafter, a photosensitive resin was applied on the ITO electrode, and a columnar spacer PSP having a height of about 5 μm was formed on the BM on the ITO electrode by photolithography. Further, a polyimide precursor varnish was applied thereon and baked to form a polyimide alignment film AL on the substrate. Next, a rubbing process was performed on the alignment film AL for both the first and second substrates. After the rubbing, the display area DA on the second substrate
The liquid crystal applied on the roll was printed on the inside of the projection WB as viewed from above, and a photocurable sealing material was applied on the outside of the projection WB as viewed from the display area DA. At this time, the liquid crystal was interrupted, and the liquid crystal and the sealing material were not in contact. Next, the substrates were bonded together so that the angle between the rubbing directions RDR of the upper and lower substrates was 90 degrees (the twist angle of the liquid crystal was 90 degrees). Thereafter, light was applied only to the seal portion to cure the seal material. At the time of light curing of the sealing material, the light was shielded by a light shielding plate so as not to irradiate the display area DA. This liquid crystal element has a polarizing plate PL
Was attached so that the transmittance of the liquid crystal panel decreases with an increase in voltage, that is, a so-called normally white mode (FIGS. 26 and 27). Further, a driving circuit DC for giving an electric signal to the liquid crystal was attached to the periphery, and a light source was installed. Thus, a TN-TFT type liquid crystal display device was completed.

In the manufactured TN-TFT type liquid crystal display device, the time for injecting liquid crystal was significantly reduced in the manufacturing process. Further, there was no display unevenness due to non-uniform cell gap.

Example 3 Except as described below,
An STN liquid crystal display device was manufactured in the same manner as in Example 1. The difference from the liquid crystal display device described in the first embodiment is that the projection WB is formed on the first substrate SUB1 provided with the electrodes.
The point is that the columnar spacer PSP is formed on the second substrate SUB2 on which the color filter CF, the black matrix BM, the planarizing film OC, and the ITO electrode are formed. Further, photosensitive resin of the same material was used for the planarizing film OC and the columnar spacer PSP (FIG. 28). In the same manner as in Example 1, in the manufactured STN-type liquid crystal display device, the liquid crystal injection time in the manufacturing process could be significantly reduced. In addition, the image quality was not deteriorated due to the non-uniform cell gap, and the contrast was high. Further, since the material of the planarizing film OC and the material of the columnar spacer PSP are the same, the adhesion of the columnar spacer to the substrate is improved.

Example 4 Except as described below,
A TN-TFT type liquid crystal display device was manufactured in the same manner as in Example 2. The difference from the liquid crystal display device described in Example 2 is that a so-called photo-alignment film capable of providing liquid crystal alignment capability by irradiating light to the alignment film is used, and the liquid crystal alignment direction is made parallel to one side of the substrate. (FIG. 29). The photo-alignment film used was 4,4'-oxydianiline as a diamine and 3,3,4,4-benzenetetracarboxylic dianhydride as an acid anhydride. This polyimide is photodegradable and exhibits liquid crystal alignment upon light irradiation. Other polyimide materials that exhibit liquid crystal alignment upon irradiation with light include cis-trans isomerization photoreactions in the molecular skeleton, such as carbon-carbon double bonds, nitrogen-nitrogen double bonds, and carbon-nitrogen. A material having a double bond is given. Other examples include a cinnamic acid skeleton and a chalcone skeleton that cause a photodimerization reaction in the molecular skeleton.

In the manufacturing process of the liquid crystal display device of the present embodiment, there was no deterioration of the TFT element due to static electricity generated during rubbing. In addition, a TN-TFT type liquid crystal display device with good display quality was obtained without the flow alignment at the time of liquid crystal injection, which is peculiar to the optical alignment film.

Embodiment 5 Next, an example in which the liquid crystal display of the present invention is applied to an IPS-TFT type liquid crystal display will be described.

First, electrodes and TFT elements as active elements were formed on the first substrate SUB1. FIG. 30 is a diagram showing a planar structure and a cross section of various electrodes in a unit pixel of the liquid crystal display device of the present invention. Glass substrate SUB1
The common electrode CEL and the scanning signal electrode SSEL are formed thereon. Further, an insulating film PAS is formed on these electrodes, and a video signal electrode SEL and a pixel electrode PEL are further formed on the TFTs made of amorphous silicon ASI.
It is formed via the element TFT. Further, an insulating layer PAS is further formed thereon. Further, the pixel is a common electrode CEL and a pixel electrode P parallel to the video signal electrode SEL.
It is divided into four by EL. A photosensitive resin was applied on the substrate having the electrode group, and a photolithography method was used to form a throat-like projection WB having a height of about 5 μm and a width of about 0.5 mm on the periphery of the effective display area of the substrate. A polyimide precursor varnish was applied and fired to form a polyimide alignment film AL on the substrate. Red on the second glass substrate SUB2,
Green and blue color filters CF were formed, and a black matrix BM was formed so as to surround each one pixel region. Next, a photosensitive resin is applied on the substrate on which the CF and BM are formed to form a flattening film 7 and at the same time, about 4 μm.
m columnar spacers were formed. The columnar spacer was arranged on the intersection of the BMs. The formation of the planarizing film and the columnar spacers may be performed in separate steps, but the planarizing film OC and the columnar spacers P
From the viewpoint of adhesion to SP, it is preferable that the same material is used. On the flattening film OC, the same polyimide precursor as that used for the first substrate SUB1 was applied and baked to form a polyimide alignment film AL on the substrate. When the alignment film surfaces of the first and second substrates SUB1 and SUB2 are combined with the alignment film surfaces facing each other, the surfaces of the alignment films AL of both substrates are aligned so that the liquid crystal alignment directions of both substrates are the same. It was rubbed. As in the first embodiment, an appropriate amount of liquid crystal is dropped on the substrate inside the projection WB as viewed from the display area DA on the first substrate SUB1, and further outside the projection as viewed from the display area. , A photocurable sealing material was applied. At this time, the liquid crystal was interrupted by the projections WB, and the liquid crystal and the sealing material were not in contact with each other. Next, the first and second substrates SUB1,
Both substrates were bonded so that the liquid crystal orientation directions of SUB2 were the same. Thereafter, light was applied only to the seal portion to cure the seal material. A polarizing plate PL was attached to this liquid crystal element to produce a liquid crystal element shown in FIG. The relationship between the polarizing plate PL and the liquid crystal alignment direction LCDR was arranged as shown in FIG.
As a result, a so-called normally-closed characteristic in which the transmittance increases with an increase in the voltage applied to the liquid crystal layer could be obtained.

Next, as shown in FIG. 32, a vertical scanning circuit SSDC, a video signal driving circuit SDC, and a common electrode driving circuit CDC are connected on a TFT substrate, and a scanning signal voltage, a video signal voltage, A timing signal was supplied to manufacture an IPS-TFT type liquid crystal display device.

FIG. 33 shows a liquid crystal display module L of the present invention.
FIG. 2 is an exploded perspective view showing each component of the CDM. MSC is a frame-shaped shield case (metal frame) made of a metal plate, DW is its display window, LCDP is a liquid crystal display panel,
BCB is a power supply circuit board, PDF is a light diffusion plate, LG is a light guide, RFF is a reflection plate, BL is a backlight fluorescent tube, BLC
Reference numeral denotes a backlight case, and the respective members are stacked in a vertical arrangement as shown in the figure to assemble a module LCDM. An inverter circuit board IVC is connected to the backlight fluorescent tube BL, and serves as a power supply for the backlight fluorescent tube BL.

In the manufactured IPS-TFT type liquid crystal display device, the time for injecting liquid crystal in the manufacturing process was significantly reduced. In addition, the image quality is not deteriorated due to the non-uniform cell gap, and the columnar spacers are arranged on the BM, so that light leakage around the spacers can be suppressed, and the contrast ratio is about 3%.
A high contrast of 00: 1 was obtained.

Embodiment 6 The liquid crystal display device of this embodiment is
IPS-TFT similar to the liquid crystal display device described in Embodiment 5
This is a liquid crystal display device. The difference from the fifth embodiment is that the color filter CF is formed on the same substrate as the substrate on which the electrode group is formed.

In the same manner as in Example 5, an electrode and a TFT element as an active element were formed on the first substrate SUB1.
Next, a photosensitive resist in which a pigment is dispersed and colored is applied to the substrate, and is exposed and developed using a photomask. By repeating this process three times for red, blue, and green pigments,
Three color filters CF of red, blue and green were formed on the first substrate SUB1. Further, a photosensitive planarizing film OC was further applied, exposed, and developed to form a planarizing film OC and a columnar spacer PSP. FIG. 34 shows a cross-sectional view of this substrate. Next, using a photosensitive resin on the second substrate SUB2,
When overlapped with the first substrate SUB1, the effective display area D
A rounded protrusion WB is provided at a position arranged on the periphery of A. Thereafter, an IPS-TFT type liquid crystal display device was manufactured in the same manner as in Example 5. In the manufactured IPS-TFT type liquid crystal display device, the time for injecting liquid crystal was significantly reduced in the manufacturing process. Further, since the color filters are formed on the TFT substrate, the first substrate and the second substrate can be easily aligned, and the yield is improved. By arranging the columnar spacers on the BM, light leakage around the spacers could be suppressed, and a high contrast of about 350: 1 was obtained, by arranging the columnar spacers on the BM without any cell gap nonuniformity. .

[Embodiment 7] The liquid crystal display device of this embodiment is
IPS-TFT similar to the liquid crystal display device described in Embodiment 5
This is a liquid crystal display device. The difference between the present embodiment and the fifth embodiment is that the electrode structure is a structure bent in a “C” as shown in FIG. 23, and therefore, the initial alignment direction of the liquid crystal is parallel to the short side of the substrate. It is. Further, in this embodiment,
The same photo-alignment film as in Example 4 was used. Further, the liquid crystal was roll-printed, and the rotation direction and the traveling direction of the roll were parallel to the initial alignment direction of the liquid crystal and the short side of the substrate.

In the manufactured IPS-TFT type liquid crystal display device, the time for injecting liquid crystal was significantly reduced in the manufacturing process. By arranging the columnar spacers on the BM, light leakage around the spacers could be suppressed without deterioration in image quality due to non-uniform cell gap. Further, there is no problem of alignment disorder due to the flow alignment at the time of liquid crystal injection, which is a problem in a liquid crystal display device using a conventional photo-alignment film, and a highly uniform alignment is obtained, and a high contrast of about 350: 1 is obtained. Was.

Comparative Example 1 Except for the following manufacturing steps,
In the same manner as in Example 5, an IPS-TFT type liquid crystal display device was manufactured. The difference from the fifth embodiment is that the first substrate SU
The point is that the spacer for controlling the distance between B1 and the second substrate SUB2 is not a columnar spacer but spherical spacer beads are dispersed. In the liquid crystal display device manufactured by this method, since the spacers are dispersed in the display area, light leaks around the spacers during black display, the black luminance increases, and a contrast of only about 150: 1 can be obtained. . Further, unevenness occurred on the periphery of the display surface, which was considered to be due to the difference in the gap between the substrates. If you take a closer look,
Dispersed spacer beads are sandwiched between the upper protrusion provided on the periphery of the effective display area on the first substrate and the second substrate, and the gap between the substrates becomes thicker around this portion by the diameter of the spacer beads. Turned out to be.

Comparative Example 2 Except for the following manufacturing steps,
In the same manner as in Example 7, an IPS-TFT type liquid crystal display device was manufactured. In this comparative example, no upper protrusion WB is provided on the first substrate SUB1 having the electrode group. Spacer beads having a diameter corresponding to the cell gap interval were mixed in the sealing material. An opening for liquid crystal injection was provided in the seal portion. After the substrates are bonded and the sealing material is cured, an empty cell into which no liquid crystal has been injected is placed in a vacuum chamber, and the pressure inside the cell is reduced. Then, after the liquid crystal was brought into contact with the opening provided in the seal portion, the inside of the chamber was gradually returned to the atmospheric pressure, and the liquid crystal was injected using a pressure difference between the inside and outside of the cell. After injecting the liquid crystal, the opening provided in the seal portion was sealed with an ultraviolet curable resin. Observing the manufactured liquid crystal display device,
Fluid alignment unevenness was observed along the end face from the liquid crystal injection port as if the liquid crystal had flowed. Upon detailed observation, it was found that the fluid alignment unevenness was caused by the liquid crystal molecules being aligned along the flow of the liquid crystal because the liquid crystal alignment regulating force of the optical alignment film was weak.

Providing the protrusions on the periphery of the effective display area on one of the substrates of the liquid crystal display device makes it possible to arrange the liquid crystal layer on the substrate by printing or the like, thereby greatly shortening the liquid crystal injection time. Shortening becomes possible. In addition, since the liquid crystal does not contact the uncured sealing material, the liquid crystal material is less contaminated. Further, by arranging the liquid crystal layer on the substrate by printing or the like, even when using an alignment film having a weak liquid crystal alignment regulating force, such as a photo alignment method,
There is no alignment disturbance due to the flow during liquid crystal injection. By using a columnar spacer, a spacer can be arranged in a non-display region, so that a high-contrast liquid crystal display device can be obtained. Furthermore, since the spacers are not arranged in a protruding shape, the uniformity of the cell gap is high. Further, since the back projections and the columnar spacers are separate substrates, there is no excess or shortage of liquid crystal.

[0053]

According to the present invention, a high-contrast liquid crystal display device can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a cross-sectional structure of a liquid crystal display device of the present invention.

FIG. 2 is a schematic plan view of the liquid crystal display device of the present invention.

FIG. 3 is a schematic cross-sectional view of the vicinity of a seal portion of the liquid crystal display device of the present invention.

FIG. 4 is a schematic plan view of the liquid crystal display device of the present invention.

FIG. 5 is a schematic plan view of the liquid crystal display device of the present invention.

FIG. 6 is a schematic plan view of the liquid crystal display device of the present invention.

FIG. 7 is a schematic plan view of the liquid crystal display device of the present invention.

FIG. 8 is a schematic plan view of the liquid crystal display device of the present invention.

FIG. 9 is a schematic diagram illustrating a cross-sectional structure of a liquid crystal display device of the present invention.

FIG. 10 is a schematic plan view of a liquid crystal display device of the present invention.

FIG. 11 is a schematic diagram illustrating a cross-sectional structure of a liquid crystal display device of the present invention.

FIG. 12 is a schematic diagram showing a cross-sectional structure of a liquid crystal display device of the present invention.

FIG. 13 is a diagram illustrating an example of a circuit system configuration in a liquid crystal display device according to a third embodiment.

FIG. 14 is a schematic view showing a cross-sectional structure of a liquid crystal display device of the present invention.

FIG. 15 is a view showing the principle of a liquid crystal display by a horizontal electric field method.

FIG. 16 is a diagram showing definitions of an initial orientation direction of a liquid crystal, a polarization axis, and an angle formed by an electric field direction in a lateral electric field mode.

FIG. 17 is a schematic diagram showing a cross-sectional structure of a liquid crystal display device of the present invention.

FIG. 18 is a schematic view showing a cross-sectional structure of a liquid crystal display device of the present invention.

FIG. 19 is a schematic view showing a cross-sectional structure of a liquid crystal display device of the present invention.

FIG. 20 is a schematic view showing a cross-sectional structure of a liquid crystal display device of the present invention.

FIG. 21 is a diagram showing a relationship between an initial alignment direction of liquid crystal and a polarization axis of a polarizing plate of the in-plane switching mode liquid crystal display device of the present invention.

FIG. 22 is a schematic view illustrating a cross-sectional structure of a liquid crystal display device of the present invention.

FIG. 23 shows a horizontal electric field type liquid crystal display device of the present invention.
FIG. 4 is a schematic diagram showing an example of an element structure in which electrodes are formed in a “C” shape.

FIG. 24 is a schematic view showing a cross-sectional structure of a liquid crystal display device of the present invention.

FIG. 25 is a schematic plan view of a liquid crystal display device of the present invention.

FIG. 26 is a schematic view showing a cross-sectional structure of a liquid crystal display device of the present invention.

FIG. 27 is a schematic plan view of a liquid crystal display device of the present invention.

FIG. 28 is a schematic view showing a cross-sectional structure of a liquid crystal display device of the present invention.

FIG. 29 is a schematic plan view of a liquid crystal display device of the present invention.

30A and 30B are a schematic plan view and a schematic cross-sectional view of a unit pixel of the in-plane switching mode liquid crystal display device of the present invention.

FIG. 31 is a schematic view showing a cross-sectional structure of a liquid crystal display device of the present invention.

FIG. 32 is a schematic diagram showing a circuit configuration according to a fifth embodiment.

FIG. 33 is an exploded perspective view showing various components of the liquid crystal display device according to the fifth embodiment.

FIG. 34 is a schematic diagram illustrating a cross-sectional structure of a substrate of the liquid crystal display device described in Embodiment 6.

[Explanation of symbols]

SUB1, SUB2, SUB, SUB '... substrate, PSP
... columnar spacers, WB ... trough-like projections, SL1 ... seal portion, SL2 ... sealant, LC ... liquid crystal layer, PE ... electrodes, PA
S: insulating film, AL: alignment film, CF: color filter, O
C: flattening film, PX: pixel area, BM: black matrix, EF: electric field direction, LCDR: initial alignment direction of liquid crystal, LCM: liquid crystal molecules, CEL: common electrode, SSEL ...
Scanning signal electrode, SEL: video signal electrode, PEL: pixel electrode, ASI: amorphous silicon, TFT: TFT element, PL: polarizing plate, PLT: polarizing transmission axis of polarizing plate, SS
DC: vertical scanning circuit, SDC: video signal driving circuit, CD
C: common electrode drive circuit, VCL: power supply circuit and controller, LCDM: liquid crystal display module, MSC: shield case, DW: display window, LCDP: liquid crystal display panel, P
DF: light diffusion plate, LG: light guide, RFF: reflection plate, BL
… Backlight fluorescent tube, BLC… backlight case,
IVC: Inverter circuit board, BCB: Power supply circuit board.

Continued on the front page (72) Inventor Kenji Okishiro 7-1-1, Omika-cho, Hitachi City, Ibaraki Prefecture Inside Hitachi Research Laboratory, Hitachi, Ltd. (72) Inventor Hidetoshi Abe 7-1-1, Omika-cho, Hitachi City, Ibaraki Prefecture Katsumi Kondo Inventor Katsumi Kondo 7-1-1, Omika-cho, Hitachi City, Ibaraki Prefecture F-term (reference) 2H089 LA09 LA16 MA07Y NA14 NA15 NA17 NA22 NA24 NA25 NA32. EA04 EA05 EB02 EC02 EC03 ED03 ED15 ED20 FA01 FA02 FB01 FB15 GB01 JA08 JA13

Claims (17)

[Claims] 1. A first and second substrate, at least one of which is transparent, a liquid crystal layer disposed between the first and second substrates, and a seal unit for bonding the first and second substrates. An electrode group for applying a voltage to a liquid crystal disposed between the first and second substrates, wherein the first substrate and the second substrate are disposed on the first substrate. A columnar spacer for controlling a substrate interval between the substrates; a projection on an edge of an effective display area of the substrate provided on the second substrate; and an arrangement of the seal portion in a peripheral cross-sectional structure. Is a liquid crystal display device in which a liquid crystal, a truncated protrusion, and a seal portion are arranged in this order. 2. The liquid crystal display device according to claim 1, wherein a sealing material used for the sealing portion is a photocurable resin. 3. The liquid crystal display according to claim 1, wherein a black matrix for shielding a boundary between the color filters is formed on the first substrate, and the columnar spacer is formed on the black matrix. apparatus. 4. The liquid crystal display device according to claim 3, wherein the liquid crystal display device is in a normally black mode in which the transmittance increases from a low voltage to a high voltage as the applied voltage increases. 5. The liquid crystal display device according to claim 3, wherein a flattening film is formed on the color filter and the black matrix, and a material of the columnar spacer is the same as the flattening film. 6. The liquid crystal display device according to claim 1, wherein an alignment control film is formed between the liquid crystal layer and the substrate, and the alignment control film is a polymer film capable of imparting liquid crystal alignment ability by light irradiation. 7. The liquid crystal display device according to claim 6, wherein the alignment direction of the long axis of the liquid crystal molecules on the alignment control film is substantially parallel to any one side of the substrate. 8. The liquid crystal display device according to claim 1, wherein the trapezoidal projection has an opening. 9. A first and second substrate, at least one of which is transparent, a liquid crystal layer disposed between said first and second substrates, and a sealing portion for bonding said first and second substrates. An electrode group formed on one of the first and second substrates to apply an electric field substantially parallel to the substrate surface with respect to the liquid crystal layer; and an electrode group interposed therebetween. In a liquid crystal display device provided with a pair of polarizing plates, a columnar spacer for controlling a distance between the first substrate and the second substrate is provided on the first substrate; The seal is provided on the periphery of the effective display area of the second substrate, and in the cross-sectional structure of the periphery of the seal, the arrangement is such that the liquid crystal, the projection formed on the substrate, and the seal are arranged in this order. Liquid crystal display device arranged. 10. The liquid crystal display device according to claim 9, wherein a sealing material used for the sealing portion is a photocurable resin. 11. The black matrix according to claim 9, wherein a black matrix that shields a boundary between the color filters is formed on the first substrate,
The liquid crystal display device, wherein the columnar spacer is formed on the black matrix. 12. The liquid crystal layer according to claim 11, wherein said liquid crystal layer has a refractive index anisotropy Δn and a thickness d of 0.2 μm.
m <d · Δn <0.4 μm, the polarization axes of the pair of polarizing plates are substantially orthogonal to each other, and the alignment control direction of liquid crystal molecules at two interfaces between the liquid crystal layer and the pair of substrates is substantially A liquid crystal display device which is parallel, and in which the polarization axis of one of the polarizing plates and the alignment control direction of the liquid crystal molecules at the interface substantially match. 13. The liquid crystal display device according to claim 11, wherein a flattening film is formed on the color filters and the black matrix, and the material of the columnar spacer is the same as the flattening film. 14. The liquid crystal display according to claim 9, wherein an alignment control film is formed between the liquid crystal layer and the substrate, and the alignment control film is a polymer film capable of imparting liquid crystal alignment ability by light irradiation. 15. The liquid crystal display device according to claim 14, wherein the alignment direction of the long axis of the liquid crystal molecules on the alignment control film is substantially parallel to any one side of the substrate. 16. The liquid crystal display device according to claim 9, wherein the truncated projection has an opening. 17. The method of manufacturing a liquid crystal display device according to claim 1, wherein the liquid crystal layer is formed by printing, coating or dropping in an effective display area inside the cross-shaped projection on the second substrate. A method for manufacturing a liquid crystal display device, comprising a step of disposing.