JP2001296528A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a liquid crystal display device having a pretilt angle as high as >=3 deg. by a photoalignment method or ion beam alignment method and having the optical characteristics equal to or higher than a device produced by a rubbing method. SOLUTION: The method for manufacturing a liquid crystal display device includes a process of forming an alignment film 2 on a substrate (TFT substrate 3 or CR substrate 4) and subjecting the alignment film 2 to the photoaligment treatment or ion beam alignment treatment. As for the alignment film 2, an alignment film 2 consisting of a photocrosslinking polyimide or photocrosslinking polyvinylcinnamate material is formed. The irradiation angle θof light is controlled to within 15 deg. from the normal direction of the alignment film 2, and the film is subjected to two-step irradiation. Or, an alignment film consisting of a soluble polyimide or polyamic acid is formed as the alignment film 2, and the irradiation angle of the ion beam is controlled to within 40 deg. from the normal direction of the alignment film 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for forming an alignment film having a high pretilt angle by light irradiation or ion beam irradiation.

[0002]

2. Description of the Related Art In a process of manufacturing a liquid crystal display device, a rubbing method is widely used as an alignment treatment method applied to an alignment film.

The rubbing method is a method in which the surface of an alignment film made of polyimide or the like is rubbed with a buff (cloth) material to align the liquid crystal.
It is controlled by the rotation speed and the like. However, if the rubbing is insufficient, the alignment of the liquid crystal is weak and disclination occurs. On the other hand, if the rubbing is performed excessively, the alignment film is peeled off or rubbing is flawed.

Further, the buffing material is consumed when the number of rubbing shots exceeds a predetermined number, and the orientation of the liquid crystal becomes insufficient. Therefore, the buffing material needs to be periodically replaced and managed. It is also necessary to manage the garbage inside.

Further, the rubbing method has a problem that it is difficult to adapt to OCS (On Chip Spacer) which is a recent gap control technique. That is, in order to maintain the uniformity of the cell gap, for example, an OCS in which a photosensitive resin is formed in a columnar shape by lithography is provided on a substrate.
Insufficient portions around the buffing material are formed in the shaded portion of the OCS, and the portion becomes poorly oriented, causing problems such as light leakage. On the other hand, if the rubbing is performed excessively, the OCS collapses, causing a problem that a streak occurs.

[0006] Therefore, as a non-contact alignment treatment method instead of the rubbing method, a light alignment method of irradiating an alignment film with light or an ion beam alignment method of irradiating an ion beam has been studied.

As a TFT substrate of a liquid crystal display device, a technique using a low-temperature polysilicon TFT instead of a conventional high-temperature polysilicon TFT has been developed. A low-temperature polysilicon TFT is formed by forming a polysilicon film on a glass substrate by a low-temperature process of 600 ° C. or less.
It is expected to be applied to a large liquid crystal display device having a large screen and forming a T. However, in order to apply a low-temperature polysilicon TFT to a large-sized liquid crystal display device, it is necessary to increase a viewing angle.

In order to increase the viewing angle, generally, WV (w
ide view) film is used. Also, (1) IPS (In
Plane Switching): Comb-shaped electrodes are provided on the TFT substrate and TF
Driving horizontal alignment liquid crystal only with T substrate, (2) MV
A (Multi-domain Vertical Alignment): A method in which a projection is provided in a pixel and the orientation direction of the vertically aligned liquid crystal is divided into two with the projection as a boundary to increase the viewing angle. (3) AS by Sharp
V (Advanced Super View): There is a method in which a horizontal alignment panel is divided into two regions having different pretilt angles, and a viewing angle is improved by providing an optical compensation film.

However, according to the above-mentioned methods (1) to (3), the conventional TN type liquid crystal panel production line for performing the rubbing treatment cannot be used as it is, and the design, process, liquid crystal material and the like are changed. Is required. On the contrary,
According to the photo alignment method or the ion beam alignment method, the conventional TN type liquid crystal panel production line can be used as it is.
Therefore, the usefulness of the photo-alignment method or the ion beam alignment method is increasing in this respect as well.

Here, the advantages of the optical alignment method and the ion beam alignment method are summarized as follows.

No troubles such as abnormal alignment, dust, buffing, and electrostatic destruction. No complicated management process is required. Split alignment is easy and wide viewing angle is possible. Alignment of substrates with large steps is possible. is there

[0012]

However, the pretilt angle that can be achieved by the optical alignment method or the ion beam alignment method is as follows.
It is considerably smaller than the pretilt angle obtained by the rubbing method, and it is difficult to realize a high pretilt angle of 3 ° or more. For this reason, a horizontal electric field domain, that is, a reverse tilt domain is generated, the contrast is reduced, and it is difficult to obtain a high-quality display.

Accordingly, an object of the present invention is to provide a liquid crystal display device which realizes a high pretilt angle of 3 ° or more by an optical alignment method or an ion beam alignment method and has optical characteristics equal to or higher than that of a rubbing method.

[0014]

In order to realize a high pretilt angle by a photo-alignment method or an ion-beam alignment method, the present inventors use a specific alignment film material and perform light irradiation or ion beam irradiation. It has been found that it is important to perform at a specific irradiation angle.

That is, the present invention relates to a method for manufacturing a liquid crystal display device, which comprises a step of forming an alignment film on a substrate and irradiating the alignment film with light as an alignment treatment, wherein the alignment film is a photocrosslinkable polyimide or a polyimide. Provided is a method for manufacturing a liquid crystal display device, comprising forming an alignment film made of a photo-crosslinkable polyvinyl cinnamate-based material, setting the irradiation angle of light within 15 ° from the normal direction of the alignment film, and performing two-step irradiation. And a liquid crystal display device obtained by this method.

The present invention also relates to a method for manufacturing a liquid crystal display device, comprising a step of forming an alignment film on a substrate and irradiating the alignment film with an ion beam as an alignment treatment, wherein the alignment film is formed of a soluble polyimide or polyamic acid. A method for manufacturing a liquid crystal display device is provided, wherein an alignment film made of an acid-based material is formed, and an irradiation angle of an ion beam is set to be within 40 ° from a normal direction of the alignment film, and further obtained by this method. Provided is a liquid crystal display device.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings. In each of the drawings, the same reference numerals represent the same or equivalent components.

In the method of manufacturing a liquid crystal display device according to the present invention, when an alignment film on a substrate is formed by a photo-alignment method or an ion beam alignment method, when the alignment film is formed by a photo-alignment method, a photo-crosslinkable polyimide is used as the alignment film. An alignment film made of a photo-crosslinkable or photo-crosslinkable polyvinyl cinnamate-based material is formed, and FIG.
As shown in (a), the irradiation angle θ of the irradiation light L is within 15 ° from the normal direction of the alignment film 2 on the substrate 1, and irradiation is performed in two stages.

Here, as the photo-crosslinkable polyimide-based material, for example, those having a structure described in US Pat. No. 5,731,405 can be used, and as the photo-crosslinkable polyvinyl cinnamate-based material, JP-A-7-104302 can be used. What is described in a gazette etc. can be used.

As described above, by using an alignment film made of a specific alignment film material and setting the light irradiation angle to within 15 °, preferably 7 to 11 °, the pretilt obtained by the conventional photoalignment method is achieved. The pretilt angle is remarkably larger than the angle, and is equal to or greater than the pretilt angle obtained by the rubbing method, and more specifically, a pretilt angle of 4 ° or more, or even 8 ° or more can be achieved.

Light irradiation is performed in the first stage to control the alignment of liquid crystal molecules in the same manner as in the known photo alignment method (FIG. 1).
(A)) In the second step, the substrate 1 is rotated by 90 ° to irradiate light (FIG. 1 (b)) to form a pretilt angle. In the present invention, the two steps are performed. In both of the light irradiations, the irradiation angle θ is within 15 °.

The light to be irradiated preferably has a wavelength of 300 to 400 nm in both the first stage and the second stage, and preferably uses UV polarized light having a predetermined ratio of S polarized light and P polarized light.

On the other hand, in the present invention, when the alignment film on the substrate is formed by the ion beam alignment method, an alignment film made of a soluble polyimide or polyamic acid material is formed as the alignment film, and the ion beam is irradiated. The angle is set to be within 40 ° from the normal direction of the alignment film.

Here, commercially available soluble polyimide or polyamic acid materials can be used. For example, JALS445, JALS400 of Japan Synthetic Rubber Co., Ltd., etc. can be used as the soluble polyimide-based material.
ALS1033, SE7492 of Nissan Chemical Co., and the like can be used.

As described above, the alignment film made of the specific alignment film material is used, and the irradiation angle of the ion beam is within 40 °.
By setting the angle to preferably 20 to 30 °, the pretilt angle is significantly larger than the pretilt angle obtained by the conventional ion beam orientation method, and is equal to or larger than the pretilt angle obtained by the rubbing method, more specifically, 4 °. More than 6 °
A pretilt angle of more than ° can be achieved.

The method of the present invention can be applied to any liquid crystal display device substrate. In particular, the method includes a low-temperature polysilicon TFT substrate suitable for a large screen, an OCS, and an alignment film forming surface. It is suitable for a high-temperature polysilicon TFT substrate having a step of 150 nm or more.

Thus, the viewing angle can be sufficiently widened in the left-right direction without dividing the pixels, and the same viewing characteristics as that of a WV film can be achieved. Therefore, a WV film becomes unnecessary, and the product cost can be reduced.

In the present invention, an alignment film may be formed on both of the substrates facing each other of the liquid crystal panel by the above-described light irradiation or ion beam irradiation. An alignment film may be formed by irradiation, and the other may be an arbitrary alignment film including an alignment film formed by a rubbing method. Preferably, an alignment film is formed by light irradiation on both substrates facing each other, or an alignment film is formed on both substrates by ion beam irradiation.

In the present invention, as long as the alignment film is subjected to the alignment treatment by the optical alignment method or the ion beam alignment method as described above, it can be manufactured in the same manner as a known liquid crystal display device. If necessary, an optical compensation film may be used to enlarge the viewing angle, or a multi-domain panel in which pixels are divided or divided between pixels may be used. Accordingly, for example, a liquid crystal display device having a wide viewing angle of 160 ° or more in the vertical direction or 160 ° or more in the left and right direction can be realized.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below based on embodiments.

Example 1 A 3.5-type 200,000-dot low-temperature polysilicon TFT substrate having a diagonal of 8.8 cm and a CF substrate having a color filter were subjected to photo-alignment treatment.

In this case, first, as shown in FIG. 2A, the TFT substrate 3 and the CF substrate 4 are
Fifteen pieces were arranged on a panel substrate 5 of 50 mm.

Next, on each of the TFT substrate 3 and the CF substrate 4, OptoAlign M2007 manufactured by ELSICON, which is a photocrosslinkable polyimide-based material as an alignment film material.
Was applied and baked (at 180 ° C. for 1 hour) to form an alignment film having a thickness of 40 nm.

As a UV light irradiation device, ELSICON
E2-UV-600-SS-AA Exposur
e Unit was used to irradiate the alignment film with UV polarized light at an irradiation angle θ of 15 ° from the normal direction and in the alignment direction indicated by the arrow in FIG. 2A (light intensity of 300 mJ /
cm ² ). Further, the panel substrate 5 was rotated by 90 ° and similarly irradiated with light at an irradiation angle of 15 °.

As shown in FIG. 2B, the TFT substrate 3 and the CF substrate 4 thus irradiated with light are overlapped with each other, the panel substrate 5 is cut, and the TFT substrate 3 and the CF substrate 4 are bonded with a sealing material ( A liquid crystal panel was fabricated by injecting a TN liquid crystal (MJ94686, manufactured by Chisso) with a cell gap of 3.5 μm.

Comparative Example 1 A liquid crystal panel was manufactured in the same manner as in Example 1 except that a rubbing treatment was applied to the alignment film instead of the photo-alignment treatment. In this case, the rubbing treatment is performed using a buff material according to a conventional method,
The alignment was performed in the same orientation direction as in Example 1.

Evaluation of Example 1 and Comparative Example 1 The pretilt angle, contrast, transmittance (%), viewing angle, and VT characteristics of the liquid crystal panels of Example 1 and Comparative Example 1 were measured. Table 1 shows the results. FIG. 3 shows a viewing angle characteristic diagram.

[0038]

[Table 1] VT characteristics (V) Full tilt angle contrast transmittance (% ) Viewing angle V90 V50 V10 Example 1 15 ° 130.8 8.30 Vertical 109 ° 0.81 1.31 2.08 Horizontal 160 ° Comparative example 1 4 ° 125.1 8.30 Vertical 76 ° 1.52 1.85 2.34 Horizontal 124 °

From these results, it can be seen that the liquid crystal panel of Example 1 achieved a high pretilt angle of 15 °. No reverse tilt domain was observed in the liquid crystal panel of Example 1. In contrast, Comparative Example 1
A reverse tilt domain was observed in the liquid crystal panel of.

The liquid crystal panel of Example 1 is the same as that of Comparative Example 1
It can be seen that the liquid crystal panel has a contrast and transmittance equal to or higher than that of the liquid crystal panel of Comparative Example 1, and that the viewing angle characteristics are much better than the liquid crystal panel of Comparative Example 1.

Further, it was found that by attaching an optical compensation film (for example, NH film manufactured by Mitsubishi Nisseki Co., Ltd.) to the liquid crystal panel of Example 1, the vertical viewing angle could be improved. Further, according to the liquid crystal panel of the first embodiment,
When a split panel was separately manufactured, the vertical viewing angle was also improved in this case.

Example 2 As in Example 1, a 3.5-type 200,000-dot low-temperature polysilicon TFT substrate 3 and a CF substrate 4 having a diagonal length of 8.8 cm were disposed on a panel substrate 5, and then an alignment film was formed. Then, the alignment film was subjected to an ion beam alignment treatment as shown in FIG.

In this case, a polyamic acid-based material SE4792 manufactured by Nissan Chemical Co., Ltd. was applied and baked to form an alignment film having a thickness of 40 nm.

The ion beam irradiation was carried out using an ion beam irradiator manufactured by Nissin Ion Equipment Co., Ltd. under the following conditions so as to be in the orientation direction shown by the arrow in FIG.

Beam size: 200 mm × 60 mm Ion species: N ₂ ion energy: ５００1500 eV Transport speed: 20 mm / sec Incident angle: 40 degrees from the normal direction

In the first embodiment, the light irradiation is performed in two steps, in which the light irradiation is divided into two steps, whereas the ion beam irradiation is performed in one step.

As shown in FIG. 4B, the TFT substrate 3 and the CF substrate 4 that have been irradiated with the ion beam are overlapped as shown in FIG. 4B, and the panel substrate 5 is cut.
And a sealing material (cell gap 3.5μ)
m), TN liquid crystal (MJ94686 (YR00 manufactured by Chisso Corporation)
9) A liquid crystal panel (actual device) was fabricated by injecting a right spiral. The TFT substrate 3 and the CF substrate 4
Were bonded without washing after ion beam irradiation.

Further, instead of the TFT substrate 3 and the CF substrate 4, a liquid crystal panel (test cell) was similarly manufactured using a simple ITO glass substrate on which no TFT was mounted.

Comparative Example 2 A liquid crystal panel (test cell and actual device) was produced in the same manner as in Example 2 except that the alignment film was subjected to rubbing instead of ion beam alignment. In this case, the rubbing treatment was performed in the same orientation direction as in Example 2 by using a buff material according to a conventional method.

Evaluation of Example 2 and Comparative Example 2 For the liquid crystal panels of Example 2 and Comparative Example 2, the pretilt angles of the test cell and the actual device were measured. In this case, the test cell is an anti-parallel cell,
-Measurement was performed using TBA-105 manufactured by Melches GmbH, and the actual device was also measured in TN mode using TBA-105.

Further, with respect to the actual devices of the liquid crystal panels of Example 2 and Comparative Example 2, the twist angle, anchoring energy and voltage holding ratio of the molecular alignment film were measured. Here, the anchoring energy of the actual device was measured using an LCD analyzer LCA-LU3 manufactured by Meishi Technica. Table 2 shows the results.

[0052]

[Table 2] Twist angle Eneruki Bu over the flop Rechiruto angle molecular alignment anchor link Bu voltage holding ratio test cell Jitsudebaisu Example 2 5.3 ° 6.5 ° 89.5 ° 22 × 10 ^-4 m / N 97% (75 ° C.) Comparative Example 2 3.4 ° 4.3 ° 90.4 ° 4.3 × 10 ^-4 m / N 98% (75 ° C.)

From Table 2, it can be seen that the liquid crystal panel of Example 2 has a larger pretilt angle than the liquid crystal panel of Comparative Example 2. The liquid crystal panel of Example 2 did not show a reverse tilt domain, but the liquid crystal panel of Comparative Example 2 showed a reverse tilt domain.

The anchoring energy of the liquid crystal panel of Example 2 is larger than that of Comparative Example 2.
This indicates that the liquid crystal panel of Example 2 has a larger alignment regulating force than the liquid crystal panel of Comparative Example 2.

Generally, when ion beam orientation treatment is performed on a TFT substrate, surface contamination of the TFT due to the ion beam is concerned. In Table 2, the voltage holding ratios of Example 2 and Comparative Example 2 are almost the same. Therefore, it can be seen that the liquid crystal panel of Example 2 has less surface contamination of the TFT.

Example 3 (1) Test cell (substrate with ITO, size 29 mm)
× 35 mm), a soluble polyimide-based or polyamic acid-based material shown in Table 3 was applied as an alignment film material, and baked to form an alignment film having a thickness of 45 nm.

The ion beam irradiation was performed under the following conditions using an ion beam irradiation machine manufactured by Nissin Ion Equipment Co., Ltd.

Beam size: 200 mm × 60 mm Ion species: N ₂ , Ar or Ne (Table 3) Ion energy: １1500 eV Transfer speed: 20 mm / sec Incident angle: 40 ° to 60 ° from normal direction (Table 3)

The test cell having the alignment film thus formed is
An anti-parallel cell with a cell gap of 25 μm was assembled, and the pretilt angle was measured. Table 3 shows the results. Table 3
Therefore, the pretilt angle largely depends on the irradiation angle and the material of the alignment film.
It turns out that it is necessary to be within °.

[0060]

[Table 3] Table Note * 1: JALS1033 manufactured by Japan Synthetic Rubber Co., Ltd. * 2: JALS445 manufactured by Japan Synthetic Rubber Co., Ltd. * 3: JALS400 manufactured by Japan Synthetic Rubber Co., Ltd. * 4: SE7492 manufactured by Nissan Chemical Industries, Ltd.

(2) A liquid crystal panel of an actual device corresponding to the test cell No. 7 in Table 3 was manufactured as follows.

That is, a 3.3 cm 1.3 type 786,000 dots XGA high temperature polysilicon TFT substrate and CF
The substrate was subjected to an ion beam alignment treatment.

In this case, an 8-inch wafer was used as the panel substrate 5 for the TFT substrate. Further, the TFT substrate had OCS, the step was about 200 nm in the pixel requiring alignment, and the taper angle was 11 °.

In the ion beam alignment treatment, an alignment film material made of the same soluble polyimide as No. 7 in Table 3 was used.
Each of the TFT substrate 3 and the CF substrate 4 was irradiated with an ion beam in the orientation direction shown in FIG. The ion beam irradiation conditions were the same as in the above (1).

The ion beam irradiated TFT substrate 3 and CF
The substrate 4 is cut off from the panel substrate 5 and is superposed in the direction shown in FIG. 5B. The TFT substrate 3 and the CF substrate 4 are bonded together with a sealing material (cell gap 3.4 μm).
A liquid crystal (MJ99220 manufactured by Merck) was injected to prepare a liquid crystal panel 6.

Comparative Example 3 A liquid crystal panel was manufactured in the same manner as in Example 3 (2) except that the alignment film was subjected to a rubbing treatment instead of the ion beam alignment treatment. In this case, the rubbing treatment was performed using rayon as a buff material and under conditions optimized so that the OCS did not collapse and a sufficient orientation without disclination was obtained.

Evaluation of Example 3 and Comparative Example 3 (1) The pretilt angles of the liquid crystal panel (actual device) of Example 3 (2) and the liquid crystal panel of Comparative Example 3 were measured in the same manner as in Example 2. Further, the contrast, transmittance, and domain residual ratio were measured. Here, the domain residual ratio is the difference in transmittance between 0 seconds and 60 seconds after the change when white display (signal voltage 0.5 V) is changed to black display (signal voltage 4.5 V). If this value is 1% or less, the afterimage level is good. Table 4 shows the results.

[0068]

[Table 4] Flop Rechiruto angle contrast transmittance preparative Bu main residual rate in Example 3 (No.7) 5.6 ° Example 3 (Jitsudebaisu) 8.1 ° 313 19.2% -0.28 Comparative Example 3 7.8 ° 308 17.6% -0.24

From Table 4, it can be seen that the liquid crystal panel (actual device) of Example 3 subjected to the ion beam alignment treatment has optical characteristics equal to or higher than the liquid crystal panel of Comparative Example 3 subjected to the rubbing treatment. Further, since the liquid crystal panel of Example 3 had a sufficiently high pretilt angle of 8 ° or more, the domain residual ratio was low, and a clear image could be obtained.

(2) When three liquid crystal panels of Example 3 and Comparative Example 3 were used to perform three-panel projector display, the projector display using the liquid crystal panel of Example 3 was the same as that of Comparative Example 3. The contrast and the transmittance were equal to or higher than the projector display using the liquid crystal panel.

(3) A screen was displayed on the projector screen, and a defect mode inspection for inspecting spots, scratches, unevenness, defects, and the like was performed. As a result, in the liquid crystal panel of Comparative Example 3,
The following defects were caused by the rubbing treatment.

Rubbing flaw: 5.6% Minute luminescent spot due to peeling of alignment film or OCS collapse:
8.3% rubbing line: 3.1%

On the other hand, in the liquid crystal panel of the third embodiment,
There were no such defects, and the yield was high.

Example 4 A liquid crystal having an alignment film subjected to photo-alignment treatment in the same manner as in Example 1 except that a 3.3 cm 1.3-type 786,000 dots XGA-compatible high-temperature polysilicon TFT substrate and a CF substrate were used. A panel was prepared.

Comparative Example 4 A liquid crystal having an alignment film subjected to a photo-alignment treatment in the same manner as in Comparative Example 1 except that a 3.3 cm 1.3-type 786,000 dots XGA-compatible high-temperature polysilicon TFT substrate and a CF substrate were used. A panel was prepared.

Evaluation of Example 4 and Comparative Example 4 With respect to the liquid crystal panels of Example 4 and Comparative Example 4, the pretilt angle, the contrast, and the transmittance were measured, and a screen was displayed in the same manner as described above, and the defect mode was inspected. .

As a result, the liquid crystal panel of Example 4 had a pretilt angle of 12 °, a contrast of 316, and a transmittance of 19.0.
%, The liquid crystal panel of Comparative Example 4 had a pretilt angle of 8.3 °, a contrast of 313, and a transmittance of 18.2%, and both showed similar values.

In the inspection of the failure mode, the liquid crystal panel of Comparative Example 4 had rubbing flaws of 4.9% and rubbing stripes of 6.3%, but the liquid crystal panel of Example 4 found a failure mode due to the rubbing treatment. High yield.

[0079]

According to the present invention, it is possible to achieve a high pretilt angle of 4 ° or more by a photo-alignment method or an ion beam alignment method and obtain a liquid crystal display device having optical characteristics equivalent to or better than that of a rubbing method. Become. Therefore, the conventional TN
In a liquid crystal display device manufacturing line, a liquid crystal display device having a wide viewing angle can be manufactured at low cost only by changing the alignment treatment process of the alignment film from the rubbing method to the optical alignment method or the ion beam alignment method. .

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of an irradiation angle of light in a photo-alignment method.

FIG. 2 is an explanatory view of an orientation processing direction of a substrate.

FIG. 3 is a view angle characteristic diagram of a liquid crystal panel.

FIG. 4 is an explanatory diagram of an orientation processing direction of a substrate.

FIG. 5 is an explanatory diagram of an orientation processing direction of a substrate.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Substrate, 2 ... Orientation film, 3 ... TFT substrate, 4 ... C
F substrate, 5: panel substrate, 6: liquid crystal panel, L:
light

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Hideaki Kato 6-35 Kita Shinagawa, Shinagawa-ku, Tokyo Sony Corporation F-term (reference) 2H090 HB08Y HB13Y LA04 MA11 MB12 MB12 MB14

Claims (5)

[Claims] 1. A method for manufacturing a liquid crystal display device, comprising: forming an alignment film on a substrate, and irradiating the alignment film with light as an alignment treatment, wherein the alignment film is a photo-crosslinkable polyimide or a photocrosslinkable polyvinyl. A method for manufacturing a liquid crystal display device, comprising: forming an alignment film made of a cinnamate-based material; setting an irradiation angle of light within 15 degrees from a normal direction of the alignment film; 2. A method for manufacturing a liquid crystal display device, comprising: forming an alignment film on a substrate, and irradiating the alignment film with an ion beam as an alignment process, wherein the alignment film is made of a soluble polyimide or polyamic acid-based material. Is formed, and the irradiation angle of the ion beam is set to 40 from the normal direction of the alignment film.
The method for manufacturing a liquid crystal display device, wherein the angle is within ± °. 3. The method according to claim 1, wherein an alignment film is formed on the low-temperature polysilicon TFT substrate. 4. The method according to claim 1, wherein an alignment film is formed on a high-temperature polysilicon TFT substrate. 5. A liquid crystal display device obtained by the method according to claim 1.