JP2009282552A - Method for manufacturing liquid crystal display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display with an alignment film, can stably and easily provide a proper pretilt angle of liquid crystal molecules, and to easily and accurately perform division and alignment, without increasing the number of processes by use of the alignment film. <P>SOLUTION: The alignment films 16a and 16b are formed from a material containing a mixture or polymerized product of a polymer x1 and a polymer x2. The polymer x1 changes the alignment of liquid crystal molecules from the vertical alignment as the initial state to a random horizontal alignment. The polymer x2 maintains the alignment of the liquid crystal molecules in the initial state. Such an alignment film is exposed to UV rays via an optical mask having a slit so that the film is divided into two parts by a single radiation. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a liquid crystal display device including an alignment film that sandwiches a liquid crystal layer, a method for manufacturing the liquid crystal display device, an alignment processing apparatus that gives a predetermined alignment to the alignment film, and an alignment processing method.

  Recently, liquid crystal display devices, particularly TFT (Thin Film Transistor) type liquid crystal display devices having a TN (Twisted Nematic) type display mode, are widely used. For example, they are widely used as display devices for personal computers. Yes.

  In general, a liquid crystal display device includes a pair of substrates that are held at a predetermined interval and face each other, electrodes and alignment films formed on opposite surfaces of each substrate, and a liquid crystal layer inserted between the alignment films. It is configured. An electrode on one substrate is formed as a common electrode, and an electrode on the other substrate is formed as a pixel electrode. The pixel electrode is often provided together with an active matrix. Moreover, an electrode may be provided only on one board | substrate (for example, IPS mode). Any substrate is provided with a black matrix or a color filter.

  In the conventional liquid crystal display device, the alignment film is rubbed, and the liquid crystal molecules of the liquid crystal layer are aligned in a predetermined direction. Since this rubbing is an operation of rubbing the alignment film with a cloth such as rayon, dust generation occurs when the cloth is brought into a clean room. In addition, static electricity is generated by rubbing, and the active matrix TFT may be destroyed. Therefore, the inventors of the present invention proposed a technique for performing an alignment treatment by irradiating an alignment film with ultraviolet rays in Japanese Patent Application No. 9-354940, and further improved the alignment in Japanese Patent Application No. 11-72085. We proposed a technology that achieves tilted vertical alignment by irradiating the film with ultraviolet rays obliquely. Specifically, as shown in FIG. 37, the surface of the polyimide alignment film 501 is irradiated with ultraviolet rays, for example, from an angle of 45 °, and as a result, the liquid crystal molecules 502 are aligned.

FIG. 38 shows a typical relationship between the pretilt angle and the amount of ultraviolet irradiation realized by the method of Japanese Patent Application No. 11-72085. From the relationship shown in the drawing, when the amount of ultraviolet radiation is small and the pretilt angle is large, a black spot is generated at a site centered on a spacer arranged to maintain the inter-substrate distance (cell gap) of the liquid crystal display device. On the other hand, if the amount of ultraviolet radiation is too large, flow alignment occurs due to liquid crystal injection, both of which are the main causes of display defects. In this case, the appropriate range of the pretilt angle at which a good image display can be obtained is a narrow range of 1.0 ° or less centered around 89 °.

  In the method of Japanese Patent Application No. 11-72085, the alignment film is irradiated with ultraviolet rays obliquely from a predetermined angle. Therefore, the angle dependency of the ultraviolet intensity is strong and a variation of about ± 10% occurs in the alignment film surface. Referring to the characteristic curve of FIG. 38, the variation of the pretilt angle is about ± 0.2% with the variation of the ultraviolet intensity, and the error occurring in the pretilt angle is not negligible. Become. For this reason, the probability that a display defect will occur in the image increases, and the reliability may be impaired.

  Thus, according to the technique of Japanese Patent Application No. 11-72085, a simple alignment process can be performed on the alignment film without rubbing, but the amount of change in the pretilt angle with respect to the change in the amount of ultraviolet irradiation is large. There is a problem that proper ultraviolet irradiation is difficult.

  Furthermore, in consideration of improving the contrast on the display screen and preventing the reversal of display brightness and darkness, an alignment technique has been proposed in which the alignment film is irradiated with ultraviolet rays from different directions and divided alignment is performed within the pixel. In this case, specifically, as shown in FIGS. 39A and 39B, when the alignment film 611 is divided into two parts, an optical mask 601 in which a slit 602 is formed is disposed on the alignment film 611. Then, ultraviolet parallel light is irradiated from the upper side of the optical mask 601 from the oblique direction, and then parallel light is irradiated again from the oblique direction having different angles (Japanese Patent Laid-Open No. 11-133429).

  As described above, when the divisional alignment is performed, it is necessary to irradiate the alignment film with the number of ultraviolet rays corresponding to the number of divisions, which inevitably increases the number of processes.

  Furthermore, in this case, there is a problem of bending of the optical mask. That is, as shown in FIG. 40, when the optical mask 601 is bent, this directly causes a shift in the irradiation position of the ultraviolet rays in the alignment film 611. For example, even when ultraviolet rays are irradiated in two directions with the center of the pixel as a boundary, the alignment is shifted in the center position. Currently, the size of glass substrates is increasing year by year, and use of substrates up to 1 m square size is under consideration. Even if the thickness of the optical mask is 1 cm, the calculation reveals that the central portion of the optical mask bends by several tens of μm, which leads to a design shift that cannot be ignored.

  As described above, when it is attempted to perform divisional alignment for further improvement of the liquid crystal image, in addition to the difficulty of oblique irradiation of ultraviolet rays, the process is inevitably complicated, and the required accuracy is extremely strict. The current situation has serious problems.

  The present invention has been made in view of the above-mentioned problems, and has a simple structure and enables simple alignment processing without rubbing, and can obtain an appropriate pretilt angle of liquid crystal molecules extremely stably and easily. It is an object of the present invention to provide a liquid crystal display device including an alignment film and a method for manufacturing the same.

Furthermore, the present invention makes it possible to perform divisional alignment easily and accurately without increasing the number of processes, improving the contrast on the display screen, preventing reversal of the display brightness, and reducing disclination lines. An object of the present invention is to provide an alignment processing apparatus, an alignment processing method, a liquid crystal display device, and a manufacturing method thereof that realize an extremely bright liquid crystal screen.

  As a result of intensive studies, the inventors have arrived at the following aspects of the invention.

  In a liquid crystal display device according to a first aspect of the present invention, there is provided a liquid crystal display device including a pair of substrates each having an alignment film facing each other and maintained at a predetermined interval, and a liquid crystal layer inserted between the alignment films. The alignment film is made of a material having a predetermined initial alignment property with respect to liquid crystal molecules of the liquid crystal layer and including at least two kinds of polymers having different pretilt angle change rates in response to ultraviolet irradiation, and the alignment film has ultraviolet rays. The liquid crystal molecules are adjusted to a desired pretilt angle by irradiation.

  In this case, it is preferable that one of the two types of polymers changes the orientation of the liquid crystal molecules from the initial state, and the other maintains the orientation of the liquid crystal molecules in the initial state. Specifically, the initial state is vertical alignment, the alignment before the change by the one polymer is vertical alignment, and the alignment after the change is horizontal alignment or random horizontal alignment.

  In the liquid crystal display device according to the first aspect, the alignment film is made of a material including at least two kinds of polymers having a predetermined orientation with respect to liquid crystal molecules and having different pretilt angle change rates in response to ultraviolet irradiation. By appropriately selecting each polymer, it is possible to appropriately adjust a desired pretilt angle and realize a stable pretilt angle that does not vary with the amount of ultraviolet irradiation. Specifically, the orientation of liquid crystal molecules in one polymer is changed from the initial state (for example, vertical orientation), for example, random horizontal orientation or horizontal orientation, and the other polymer is maintained in the initial state for liquid crystal molecules. It shall be. In the manufacturing process, the ratio of each of these polymers is adjusted as appropriate, and ultraviolet irradiation is started, and one polymer reaches a state where liquid crystal molecules are randomly horizontally aligned by a certain time, while the other polymer The alignment state of the liquid crystal molecules is maintained in the original state. That is, after the elapse of the certain time, the pretilt angle corresponding to the ratio of the other polymer is stably maintained without depending on the UV irradiation amount.

  A second aspect is a method for manufacturing the liquid crystal display device. That is, when an alignment film is formed on each of a pair of substrates, a liquid crystal layer is inserted between the alignment films so that the alignment films are opposed to each other, and a liquid crystal display device is manufactured by keeping the distance between the substrates constant. The alignment film is made of a material including at least two kinds of polymers having initial alignment with respect to liquid crystal molecules of the liquid crystal layer and having different pretilt angles according to ultraviolet irradiation, and is applied to the pair of substrates. The surface of the alignment film is irradiated with ultraviolet rays from an oblique direction to achieve a desired alignment with respect to the liquid crystal molecules of the liquid crystal layer.

  As a result, the liquid crystal display device of the first aspect described above, that is, by appropriately selecting each polymer used as the material of the alignment film, the desired pretilt angle can be appropriately adjusted and stable without fluctuation depending on the amount of ultraviolet irradiation. It becomes possible to manufacture a high-performance liquid crystal display device that realizes a pretilt angle.

  The third aspect is directed to a liquid crystal display device that includes a pair of substrates that face each other with an alignment film facing each other and that is maintained at a predetermined interval, and in which a liquid crystal layer is inserted between the alignment films. In the liquid crystal display device, the liquid crystal is subjected to a plurality of divisional alignments at a predetermined boundary, and the surface energy of the alignment film becomes a maximum value or a minimum value at the boundary of the alignment division, and decreases as the distance from the boundary decreases. It is characterized by becoming larger.

  The fourth aspect is directed to an alignment processing apparatus as a specific example for realizing the liquid crystal display device of the third aspect described above. This alignment processing apparatus irradiates the alignment film with ultraviolet rays and aligns the liquid crystal provided on the alignment film. The alignment processing apparatus is provided with a light source that irradiates ultraviolet scattered light and a light source provided under the light source to form a slit. The optical mask is disposed above the alignment film, and the diffused light spreading around the slit is generated by irradiating the optical mask with scattered light from the light source, and the diffusion The alignment film is irradiated with light to cause the liquid crystal to have a split alignment depending on a diffusion direction of diffused light.

  In the alignment processing apparatus of the fourth aspect, ultraviolet diffused light is irradiated from an oblique direction to the alignment film surface symmetrically with the portion immediately below the slit of the optical mask as the center of symmetry. As a result, the alignment film is automatically divided into two with the symmetry center as a boundary. In this case, the diffusion angle of the diffused light changes as the distance from the center of symmetry changes, and a liquid crystal layer with excellent visual characteristics having a large number of pretilt angles corresponding to this is realized.

  At this time, the alignment film is composed of the alignment film of the first mode (second mode), that is, two kinds of polymers, and the pretilt angle starts to change from the vertical alignment by irradiation of ultraviolet rays, and a certain ultraviolet ray irradiation amount is set. If it exceeds, it is preferable to use a pretilt angle having a constant value in the vicinity of 90 °. By using the alignment film having such properties, the vertical alignment is maintained immediately below the slit, and the pretilt angle of the liquid crystal layer is stably between 90 ° and the predetermined value according to the irradiation angle and the irradiation amount of the scattered light. Distributed.

  Further, as the alignment film, it is also preferable to use a film having a characteristic that the pretilt angle starts to change from the vertical alignment by irradiation with ultraviolet rays and returns to the vertical alignment again by irradiation with ultraviolet rays. By using an alignment film having such properties, it is possible to control the alignment directly under the slit with high irradiation intensity to be a vertical alignment. As a result, poor orientation is suppressed.

  The fifth aspect is an alignment processing method corresponding to the fourth aspect. In this case, the divisional orientation is preferably the direction of a line segment connecting the pixel centers of the substrate facing the gate electrode and / or the data electrode in relation to the gate electrode and / or the data electrode. Specifically, it is possible to divide into two parts from top to bottom, two parts from the center to right and left, four parts from center to top, bottom, left and right, and so on.

  Further, when performing the above-described divided orientation, a bank-like member is formed on the other substrate facing the one substrate provided with the gate electrode and the data electrode along the boundary of the divided orientation, It is also preferable to subject the pixel electrode of this substrate to slits that have slits formed along the boundary of divisional alignment, and to be irradiated with ultraviolet rays. Thereby, the divisional orientation by ultraviolet irradiation is promoted, the division position is clarified, and more reliable divisional orientation can be performed.

  Further, when the above-described divided orientation is performed, a bank-like member is formed on the other substrate in the vicinity of the gate electrode or the data electrode, or the gate electrode or the data is formed on the pixel electrode of the one substrate. What formed the slit-shaped drop | off so that it might correspond to the position of an electrode is also preferable as an irradiation object of an ultraviolet-ray. This corrects the inclination of the liquid crystal molecules due to the electric field generated in the vicinity of the electrodes together with the divided alignment, thereby suppressing the occurrence of disclination.

  The sixth aspect is directed to the alignment processing apparatus as in the fourth aspect. The alignment processing apparatus includes a light source for irradiating ultraviolet light and an optical mask provided under the light source, having a slit and having an ultraviolet light scattering mechanism, and the optical mask is disposed above the alignment film. By irradiating the optical mask with ultraviolet light from the light source, diffused light that spreads around the slit is generated, and the diffused light is irradiated on the alignment film, depending on the diffusion direction of the diffused light on the liquid crystal It is characterized by causing a divided orientation.

  In this case, as the scattering mechanism, the surface of the optical mask on the light source side is sandblasted, the scattering means provided in the opening of the slit (for example, the opening is sandblasted), the A predetermined prism or the like provided at the opening is suitable.

  In the alignment processing apparatus of the sixth aspect, similarly to the fourth aspect, the diffused light of ultraviolet rays is irradiated from the oblique direction to the alignment film surface symmetrically with the portion immediately below the slit of the optical mask as the center of symmetry, and the symmetry A two-part alignment is automatically generated in the alignment film with the center as a boundary. Furthermore, since the optical mask is provided with an ultraviolet light scattering mechanism, the light source is not limited to the light source that irradiates the scattered light, and a light source that irradiates parallel light can be sufficiently applied. It is possible to expand the applicable range of lamps that can be used.

  Furthermore, the slit of the optical mask is not only a part that substantially coincides with the center position of the left and right (up and down) of the pixel substantially in parallel with the data electrode (gate electrode), but also with the part or independently of the part. It is also preferable that the gate electrode is formed so as to be positioned in the vicinity of the (gate electrode) and substantially parallel thereto. In this case, it is possible to correct the tilt of the liquid crystal molecules caused by the generation of an electric field in the vicinity of the electrode in addition to the divided alignment or independently of the divided alignment.

  The seventh aspect is an alignment processing method corresponding to the sixth aspect. In this case, similarly to the fifth embodiment, various divided alignment patterns are selected according to various requests for the liquid crystal layer.

  The eighth aspect is directed to a liquid crystal display device that includes a pair of substrates that face each other with an alignment film facing each other and that is maintained at a predetermined interval, and in which a liquid crystal layer is inserted between the alignment films. In this liquid crystal display device, a pixel electrode is formed under the alignment film on one of the substrates, and the alignment due to the electric field generated at the end portion is canceled in the liquid crystal molecules corresponding to the end portion of the pixel electrode. It is characterized in that an orientation regulating force directed in the direction is given.

  In the liquid crystal display device according to the eighth aspect, the alignment due to the alignment regulating force cancels out the alignment due to the electric field, and the alignment of the liquid crystal molecules at the end becomes vertical alignment, thereby preventing the occurrence of disclination.

  The ninth aspect is a method of manufacturing a liquid crystal display device corresponding to the eighth aspect. In this case, specifically, by using the above-described various optical masks or the like, the orientation regulating force can be expressed.

  The tenth aspect is similar to the eighth aspect, and is intended for a liquid crystal display device. Under the alignment film of one of the substrates, a bus line (gate electrode, data electrode) formed between the pixel electrode and the pixel electrode. And a slit substantially parallel to the bus line is formed in the vicinity of the bus line of the pixel electrode.

  In the liquid crystal display device according to the tenth aspect, the slit formed in the pixel electrode generates a force that causes the liquid crystal molecules to tilt due to the generation of an electric field in the vicinity of the bus line. In the end, it loses its destination and inclines in the direction parallel to the slit, so that the alignment failure caused by the electric field is eliminated and the occurrence of disclination is suppressed.

  According to the present invention, a stable desired pretilt angle can be obtained even if the irradiation dose fluctuates due to oblique irradiation of ultraviolet rays onto the alignment film, so that a simple alignment process can be performed without rubbing with a simple structure. Therefore, it is possible to realize a liquid crystal display device including an alignment film that can obtain an appropriate pretilt angle of liquid crystal molecules extremely stably and easily.

  In addition, it is possible to easily and accurately perform divisional alignment without increasing the number of processes, improving the contrast on the display screen, preventing reversal of the display light and darkness, and reducing the disclination lines, and performing extremely bright liquid crystals. A screen can be realized.

It is sectional drawing which shows schematic structure of the liquid crystal display device by the 1st Embodiment of this invention. It is a characteristic view which shows a mode that the change of the pretilt angle with respect to ultraviolet irradiation amount differs greatly about the alignment film which consists of two types of polymers. It is a characteristic view which shows the change of the surface free energy with respect to the amount of ultraviolet irradiation about the orientation film which consists of 1 type of polymer. It is a characteristic view which shows the guideline for implement | achieving a suitable orientation film. It is a schematic diagram which shows the apparatus for performing an alignment process to alignment film. FIG. 6 is a characteristic diagram showing an ideal change in pretilt angle with respect to the amount of ultraviolet irradiation in the alignment film of the liquid crystal display device according to the first embodiment of the present invention. It is a schematic sectional drawing which shows the main structures of the orientation processing apparatus of 2nd Embodiment. It is a schematic sectional drawing which shows the mode of ultraviolet irradiation when the optical mask 102 bends. FIG. 6 is a characteristic diagram showing a change in tilt angle accompanying ultraviolet irradiation of an alignment film. It is a schematic sectional drawing which shows a mode that the bank-like member was provided in the board | substrate in the case of 2 division orientation. It is a schematic diagram which shows the structure of the light source (lamp) used for the orientation process of 2nd Embodiment. It is a schematic perspective view which shows a mode that a light source (lamp) is scanned with respect to an optical mask. It is a schematic diagram which shows an example which was vertically divided into two on the TFT-LCD. It is a schematic diagram which shows an example which carried out 2 division | segmentation orientation right and left on TFT-LCD. It is a schematic diagram which shows an example which carried out 4 division | segmentation orientation on the TFT-LCD vertically and horizontally. It is a schematic diagram which shows an example which carried out 4 division | segmentation orientation on the TFT-LCD vertically and horizontally. It is a schematic diagram which shows an example which carried out the vertical and 2-part dividing orientation on TFT-LCD. It is a schematic sectional drawing which shows the positional relationship of a bank-like member and a pixel electrode. It is a characteristic view showing the relationship between the width of the overlapping portion of the bank-like member and the pixel electrode and the width of the alignment failure at the end of the pixel electrode. It is a schematic diagram which shows the other example of 2nd Embodiment. It is a characteristic view which shows the examination result about the optimal value of the width | variety of the slit of the optical mask which the orientation state became favorable, and the distance of an optical mask and a board | substrate. It is a schematic sectional drawing which shows the main structures of the orientation processing apparatus of 3rd Embodiment. It is a schematic sectional drawing which shows the other example of 3rd Embodiment. It is a schematic sectional drawing which shows the other example of 3rd Embodiment. It is a schematic sectional drawing which shows the main structures of the orientation processing apparatus of 4th Embodiment. It is a schematic perspective view which shows the optical mask of an orientation processing apparatus. It is a schematic perspective view which shows the arrangement | positioning state of an optical mask. It is a schematic plan view which shows the image state of the liquid crystal display device manufactured by 4th Embodiment. It is a schematic plan view which shows the image state of the liquid crystal display device which gives only the orientation regulation of 2 divisions. It is a schematic plan view which shows the optical mask in the other example of 4th Embodiment. It is a schematic plan view which shows the optical mask in the further another example of 4th Embodiment. It is a schematic diagram which shows an example of the light source used in the further another example of 4th Embodiment. It is a schematic plan view which shows the relationship between the scattering property of a light source, and the slit of an optical mask. It is a schematic plan view which shows the pixel electrode vicinity of the liquid crystal display device of 5th Embodiment. It is a schematic sectional drawing which shows the mode of the orientation of the liquid crystal molecule in the pixel electrode in which the slit was formed. It is a schematic diagram which shows the other example of 5th Embodiment. It is a characteristic view which shows the change of the pretilt angle with respect to the amount of ultraviolet irradiation about the orientation film which consists of 1 type of polymer. It is a schematic diagram which shows a mode that the alignment of the predetermined pretilt angle produced in the liquid crystal molecule by the oblique ultraviolet irradiation with respect to the alignment film. It is a schematic sectional drawing which shows the process in the case of giving 2 division alignment to an alignment film with the conventional method. It is a schematic sectional drawing for demonstrating the inconvenience when bending arises in an optical mask.

  Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings.

(First embodiment)
In the present embodiment, a liquid crystal display device characterized by a liquid crystal alignment film and a manufacturing method thereof will be exemplified. FIG. 1 is a schematic cross-sectional view showing the main configuration of the liquid crystal display device of the present embodiment. The liquid crystal display device includes a pair of transparent glass substrates 11 and 12 facing each other with a predetermined interval, and a liquid crystal layer 13 sandwiched between the transparent glass substrates 11 and 12.

  A plurality of pixel electrodes 15 are formed on one transparent glass substrate 11 via an insulating layer 14, and a transparent alignment film 16 a is formed so as to cover the pixel electrodes 15. The color filter 17, the common electrode 18, and the alignment film 16b are sequentially stacked. The alignment films 16 a and 16 b are abutted so as to sandwich the liquid crystal layer 13 to fix the glass substrates 11 and 12, and polarizers 19 and 20 are provided outside the substrates 11 and 12. The pixel electrode 15 is formed together with an active matrix, and in the illustrated example, a data bus line 21 of the active matrix is shown. Note that the electrode may be provided only on one of the substrates (for example, in the IPS mode).

  The alignment film 16a (16b) has a predetermined alignment property with respect to the liquid crystal molecules of the liquid crystal layer 13, and the alignment with the pretilt angle of the liquid crystal molecules is performed by irradiating the liquid crystal layer 13 with ultraviolet rays from an oblique direction without rubbing. It has been realized.

  Specifically, the alignment film 16a (16b) is a material containing two types of polymers x1 and x2 having different rates of change in pretilt angle in response to ultraviolet irradiation. Here, one polymer x1 is in an initial state of alignment of liquid crystal molecules. For example, a random horizontal alignment is used, and the other polymer x2 maintains the alignment of liquid crystal molecules in the initial state, and is composed of a material including a mixture or copolymer of them. Is done. That is, the polymer x1 has extremely fast reactivity with respect to ultraviolet rays, and the pretilt angle rapidly decreases with a small amount of ultraviolet irradiation. On the other hand, the polymer x2 has extremely low reactivity to ultraviolet rays, and the pretilt angle hardly changes even when irradiated with ultraviolet rays. It is also conceivable to use a mixture or copolymer of three or more polymers having different pretilt angle change rates.

Here, when the alignment film is formed by using one kind of polymer exhibiting a predetermined change rate of the pretilt angle with respect to ultraviolet irradiation, the relationship between the ultraviolet irradiation amount (J / cm ² ) and the pretilt angle (°) is, for example, As shown in FIG. In this case, since the amount of change in the pretilt angle with respect to the change in the amount of ultraviolet irradiation is large, proper ultraviolet irradiation becomes difficult.

Therefore, the ideal relationship between the UV irradiation amount and the pretilt angle is that the pretilt angle quickly decays to the desired value when the UV irradiation amount is small, and then the pretilt angle is almost the same even if the UV irradiation amount increases. What is necessary is just to come to hold | maintain with a desired value. In the present embodiment, in order to realize the above-mentioned ideal pretilt angle, as shown in FIG. 2, the polymer x1 whose pretilt angle rapidly decreases with respect to the ultraviolet irradiation amount (J / cm ² ), and the pretilt angle is ultraviolet irradiation. The alignment film 16a (16b) is formed using a polymer x2 that hardly changes depending on the amount and shows no change.

  As the polymer of the alignment film 16a (16b), vertical alignment type polyimide or polyamic acid is used. An example is shown below.

  The polymer has an alkyl side chain (alkyl group) R as shown in Chemical Formula 1, which is considered to protrude randomly from the surface of the alignment film 16a (16b). When the surface is irradiated with ultraviolet light, photostraightening occurs in the straight chain supporting the alkyl side chain R and is cut, substantially reducing the alkyl side chain R. As a result, the pretilt angle of the liquid crystal molecules is reduced. Appears as decay. The polymer x1 has a structure in which the straight chain supporting the alkyl side chain R is much easier to cut than the polymer x2. Specifically, a site where photocleavage easily occurs, for example, a double bond site, is provided as a straight chain that supports the alkyl side chain R of the polymer x1. When this double bond site is irradiated with ultraviolet rays, photoexpansion occurs even when the irradiation amount is extremely small, and the pretilt angle is greatly attenuated in a short time.

  Here, the ratio of the polymers x1 and x2 is, for example, 20% and 80%, respectively. By the start of UV irradiation, the polymer x1 changes its state by a predetermined time, and the substantial amount of the alkyl side chain R that develops the pretilt angle is decreased to almost zero. On the other hand, since the polymer x2 does not have a double bond site or the like in the straight chain of the alkyl side chain R like the polymer x1, it maintains the initial vertical alignment state. For this reason, when the alignment film 16a (16b) is viewed as a whole after the lapse of the predetermined time, it means that the ratio of the alkyl side chain R is kept at a substantially constant value with the ratio reduced to 80. This applies to the case where only the polymer x2 is irradiated with ultraviolet rays, and the proportion of the alkyl side chain R is reduced from 100% to 80% and then becomes constant. That is, by forming the alignment film 16a (16b) by mixing or copolymerizing the ratios of the polymers x1 and x2 to 20% and 80%, respectively, ultraviolet rays are applied to the alignment film made of a material containing only the polymer x2. Irradiated, the state where the ratio of the alkyl side chain R reaches 80% is maintained, and a stable pretilt angle corresponding to the state is realized.

  Next, specific criteria for selecting the polymers x1 and x2 for realizing a suitable alignment film having the above characteristics will be described. FIG. 3 shows the relationship between the ultraviolet irradiation time (min) on the alignment film surface and the surface free energy (γs: Helmholtz free energy per unit area). The two are in a substantially proportional relationship until reaching a certain state. When the amount of ultraviolet irradiation is small, the surface energy is small, the surface free energy increases with the irradiation of ultraviolet rays, and finally becomes a substantially constant value. Here, as shown in FIG. 4A, when the surface free energy increases as the irradiation time of ultraviolet rays increases, so-called injection streaks are generated from the injection port during liquid crystal injection. When the irradiation time is further increased, the initial vertical alignment is not exhibited, and the horizontal random alignment is shifted. In other words, the inventors of the present invention have found that the surface free energy increases as the ultraviolet irradiation time (irradiation amount) increases. Region (1): State indicating vertical alignment, Region (2): Flow alignment and defects near the spacer do not occur. It was found that a state in which good image display is realized, region (3): a state in which injection streaks are generated by flow orientation, and region (4): a state in which horizontal random orientation is exhibited are sequentially shifted.

  Furthermore, as shown in FIG. 4B, if the alignment film is classified based on the surface free energy, it shifts to the region (4) by a small amount (short time) of ultraviolet irradiation depending on the properties of the polymer constituting the alignment film. Then, the film becomes horizontal random alignment (alignment film A), shifts to the region (3) with the passage of the ultraviolet irradiation time, stops almost in this state (alignment film B), still remains in the region (1), There are three types that maintain vertical alignment (alignment film C). Therefore, it is suggested that the ideal region (2) can be realized by appropriately combining the alignment films A to C.

  FIG. 4C shows the relationship between the ultraviolet irradiation amount and the pretilt angle by each combination of the alignment films A and B and the alignment films A and C. In the case where the alignment films A and B are combined, the pretilt angle continues to gradually decrease with an increase in the amount of ultraviolet irradiation, does not contribute to the improvement of the margin, and good alignment is not realized. On the other hand, when the alignment films A and C are combined, a region in which the pretilt angle hardly changes even when the ultraviolet irradiation amount changes is realized, and an alignment with a wide margin is realized.

  As described above, the polymers x1 and x2 exhibit extreme extreme properties regarding the expression of the pretilt angle, that is, the polymer x1 becomes horizontal random orientation by a small amount (short time) of ultraviolet irradiation, whereas the polymer x2 Those that still maintain the initial vertical alignment are preferred. Therefore, it is preferable to select the polymer x1 as the alignment film A (polymer) and the polymer x2 as the alignment film C on the basis of the surface free energy.

  Subsequently, in the method for manufacturing a liquid crystal display device, an alignment treatment process which is a main process of the present embodiment will be described. First, for the transparent glass substrate 11, the insulating film 14 is formed on the surface, and then the color filter 17 and the pixel electrode 15 are sequentially formed. On the other hand, the color filter 17 and the common electrode 18 are sequentially formed on the surface of the transparent glass substrate 12.

  Next, as the polymers x1 and x2 having the above properties on the surfaces of the transparent glass substrates 11 and 12, for example, a vertically oriented polyimide or polyamic acid (see Chemical Formula 1) manufactured by Nippon Synthetic Rubber Co., Ltd. is used. x1 and x2 are mixed or copolymerized at a ratio of 2: 8 to form alignment films 16a and 16b on the surfaces of the transparent glass substrates 11 and 12, respectively. And the orientation processing shown below is given to the said film using the orientation processing apparatus shown in FIG.

The alignment processing apparatus includes a light source 31 that emits unpolarized ultraviolet light, a mirror 32, and a holder 33 that supports the transparent glass substrate 11 (12) on which the alignment film 16a (16b) is formed. . The holder 33 supports the transparent glass substrate 11 (12) obliquely with respect to the optical axis of the ultraviolet rays. That is, parallel ultraviolet rays from the light source 31 are incident on the surface of the alignment film 16a (16b) at an angle of θ = 45 ° (or a predetermined angle of 45 ° or less).

  The light source 31 is a short arc type xenon mercury lamp, which includes a parabolic reflector 3104a and irradiates non-polarized ultraviolet rays substantially in parallel. The spectral distribution of the ultraviolet wavelength has a peak near 250 nm. It is. In this spectral distribution, it has been found that wavelength components of 300 nm or more do not contribute to the expression of the pretilt angle, and it is preferable to use ultraviolet rays having a wavelength of 280 nm or less in consideration of effectively expressing the pretilt angle. In addition, as an ultraviolet-ray to irradiate, about the P wave and S wave which have polarization | polarized-light, the thing of a state with more P waves than an S wave or a state of only a P wave may be used.

Using the alignment treatment apparatus having the above-described configuration, the surface of the alignment film 16a (16b) is irradiated with ultraviolet rays from an oblique angle of 45 °. At this time, the pre-tilt angle of the polymer x1 decreases when the ultraviolet irradiation amount is several tens (mJ / cm ² ), and the pretilt angle of the polymer x2 hardly changes even when the ultraviolet irradiation amount is several (J / cm ² ). Therefore, the irradiation amount of ultraviolet rays is 1 (J / cm ² ).

In consideration of the fact that each of the polymers x1 and x2 surely exhibits the above properties, regarding the relationship between the ultraviolet irradiation amount and the pretilt angle, the pre-tilt is performed when the ultraviolet irradiation amount is 0.5 (J / cm ² ) or less for the polymer x1. It is preferable that the angle change is 2 ° or more, and the polymer x2 has an ultraviolet irradiation amount of 1 (J / cm ² ) or less and a pretilt angle change of 0.5 ° or less.

When UV irradiation is actually performed under these conditions, as shown in FIG. 6, a stable pretilt angle of about 89 ° can be realized, and the UV irradiation amount is in the range of 1 ± 0.3 (J / cm ² ). The fluctuation of the pretilt angle was 0.1 ° or less. Therefore, it can be seen that a stable desired pretilt angle can be obtained even if the irradiation amount varies with oblique irradiation of ultraviolet rays.

  Subsequently, after injecting liquid crystal between the pair of transparent glass substrates 11 and 12 to form the liquid crystal layer 13, the injection port is sealed. Thereafter, the liquid crystal display device is completed through various post-processes.

  As described above, according to the present embodiment, a simple alignment process can be performed without rubbing, and an appropriate pretilt angle of the liquid crystal molecules of the liquid crystal layer 13 can be set extremely stably and easily. A liquid crystal display device including the alignment film 16a (16b) that can be obtained can be realized.

(Second Embodiment)
In the present embodiment, an alignment processing apparatus and method used when performing division alignment on an alignment film that is a constituent element of a liquid crystal display device will be exemplified. First, the outline of the present embodiment will be described. FIG. 7 is a schematic diagram showing the main configuration of the alignment processing apparatus of the present embodiment. The alignment processing apparatus includes a light source 101 that emits ultraviolet scattered light and an optical mask 102 that is provided under the light source 101 and in which a slit 111 is formed.

  As the light source 101, an ultraviolet lamp having scattering properties is used. For example, a tube-type low-pressure mercury lamp corresponds to this. The shape is the same as that of a normal long fluorescent lamp, but the gas component or the glass material of the heavy light tube is different, and ultraviolet light, particularly scattered light having a wavelength of around 250 nm is irradiated.

  The optical mask 102 is placed at a certain distance, for example, 50 μm away from the substrate 104 on which the alignment film 103 is applied or printed. A slit 111 is formed in the optical mask 102 so that the scattered ultraviolet light can be transmitted. When a mercury lamp is scanned as the light source 101 on the optical mask 102 in the direction of the arrow in FIG. 7, diffused light spreading around the slit 111 is generated, and the diffused light is irradiated to the alignment film 103, and the slit 111 A two-divided orientation is formed depending on the oblique diffusion direction of the diffused light with the boundary immediately below. As described above, the technology for realizing the oblique two-divided orientation by one ultraviolet irradiation is the first outline of the present embodiment.

  In the first skeleton, ultraviolet diffused light is radiated from an oblique direction to the surface of the alignment film 103 symmetrically with the portion immediately below the slit 111 of the optical mask 102 as the center of symmetry. As a result, the alignment film 103 is automatically divided into two parts with the symmetry center as a boundary. In this case, the diffusion angle of the diffused light changes as the distance from the center of symmetry changes, and a liquid crystal layer with excellent visual characteristics having a large number of pretilt angles corresponding to this is realized. In such an alignment film, (1) the directions in which the liquid crystal molecules are tilted are opposite to each other, (2) the alignment at the center portion to be tilted is a vertical alignment, and (3) the surface energy of the alignment film is large. Since the liquid crystal display device provided with the alignment film has a plurality of divided alignments at a predetermined boundary, the surface energy of the alignment film is: It becomes the maximum value or the minimum value at the boundary of the alignment division, and becomes smaller or larger as the distance from the boundary increases.

  Furthermore, according to the structure of the first skeleton, even if the optical mask 102 is bent, the desired divided orientation can be obtained without being affected by much. For example, as shown in FIG. 8, since the original scattered light is incident from a direction perpendicular to the optical mask 102 even when the optical mask 102 is bent, the symmetry center irradiated with the light changes. Because it does not. However, since the range of light that wraps around changes, it is necessary to design the gap between the optical mask 2 and the substrate and the width of the slit 111 in consideration of this margin.

  Further, in the present embodiment, the alignment film, which is the main component of the liquid crystal display device of the first embodiment, that is, composed of two types of polymers, the pretilt angle starts to change from the vertical alignment by the irradiation of ultraviolet rays, and a certain ultraviolet ray irradiation amount is set. If it exceeds, it is preferable to use a pretilt angle having a constant value in the vicinity of 90 °. By using the alignment film having such properties, the vertical alignment is maintained immediately below the slit 111, and the pretilt angle of the liquid crystal layer is between 90 ° and the predetermined value according to the irradiation angle and the irradiation amount of the scattered light. Stable distribution.

  As the alignment film, a film having a characteristic that the pretilt angle starts to change from the vertical alignment by irradiation with ultraviolet rays and returns to the vertical alignment again by irradiation with ultraviolet rays may be used. FIG. 9 shows the change in tilt angle associated with the ultraviolet irradiation of the alignment film in this case. As the amount of ultraviolet irradiation increases, the vertical alignment shifts from the vertical alignment, and when the ultraviolet rays are further irradiated, the pretilt angle decreases again to become the vertical alignment.

  In this case, even if it is directly under the slit 111 irradiated with a large amount of ultraviolet rays, the alignment is not horizontal alignment but vertical alignment, so that alignment disorder does not occur. Directly below the slit 111, a lot of ultraviolet rays are radiated, and in a normal alignment film, the alignment is horizontal, and the alignment orientation is not defined. Therefore, the alignment failure shines white even when no voltage is applied. It becomes an area. On the other hand, when the alignment film as in the present embodiment is used, the alignment is continuous and alignment failure does not occur, and the entire screen is surely displayed even in the black display state only by the vertical alignment. It becomes black. That is, by using an alignment film having such properties, the alignment immediately below the slit with high irradiation intensity can be controlled to a vertical alignment, and continuous alignment is performed within a predetermined pretilt angle range at a portion other than just below the slit. This prevents misalignment. Thus, the second main point in the present embodiment is to use an alignment film that is excellent in being subjected to suitable divided alignment using the alignment processing apparatus.

  Furthermore, in the present embodiment, as shown in FIG. 10A, a specific alignment state in the case of performing two-part alignment and a liquid crystal panel structure when using a bank-like member are disclosed. This is a basic configuration, and this idea is also used in the case of quadrant orientation. The liquid crystal molecules of the liquid crystal layer 114 are set so as to be inclined from the upper and lower gate electrodes 113 of the pixel electrode 118 toward the center of the pixel, or (and) the liquid crystal from the left and right data electrodes 115 of the pixel electrode 118 toward the center of the pixel. It is set so that molecules are tilted and oriented. Further, the slit 111 of the optical mask 102 is set in the center of the pixel on the TFT substrate 104a side and irradiated with ultraviolet rays, and the opposite CF side substrate 104b is similarly irradiated with ultraviolet rays obliquely. Furthermore, a bank-like member 116 made of resin or the like can be provided on the TFT substrate 104a or (and) the CF substrate 104b to help regulate the alignment direction. These are the third outline in the present embodiment.

  In the third outline, for example, as shown in FIG. 10A, the alignment regulation of the liquid crystal layer 112 is performed in the same direction as the alignment regulation due to the leakage electric field from the gate electrode 113. Thereby, the orientation is continuously changed from the vicinity of the gate electrode 115 and disclination does not occur. For example, when the orientation of the liquid crystal in FIG. 10A is reversed, disclination occurs in the vicinity of the portion indicated by the dashed circle in FIG. 10B. On the other hand, in this embodiment, since photo-alignment is used, the alignment restriction is generated on the entire display electrode surface, the response is fast, and disclination does not occur.

  Here, the action of the bank-like member will be mentioned. At present, a method of controlling the orientation by providing a bank-like member has been put into practical use. In this display, the orientation of the liquid crystal is regulated by utilizing the inclination of the side surface of the bank-like member. In this embodiment, the action of the bank-like member is utilized. For blending using only a bank-like member, it is necessary to narrow the gap between adjacent bank-like members. For example, it is desirable to take a gap of about 30 μm. However, in this case, many bank-like members exist in the display pixel. In the present embodiment, since photo-alignment is used, the gap between the bank-like members can be widened. By the way, when performing photo-alignment, it is not always necessary that the bank-like member positively has an alignment regulating force. When alignment is performed by optical alignment, there is a possibility that the position of the central portion shown in FIG. For example, when the slit width of the optical mask is about 20 μm, it is difficult to reliably bring the center of the alignment division at the center. Ensuring the division point of this orientation division by forming a bank is a major role of the bank-like member in this embodiment.

  Based on the contents of the first to third points described above, a specific configuration of the present embodiment will be described. As the alignment film for performing photo-alignment, vertical alignment or horizontal alignment polyimide, polyamic acid, and a cross-linked resin film (for example, polyvinyl cinnamate) were used. Needless to say, the materials are not limited to these, and the materials are not limited to vertical alignment and horizontal alignment. In the present embodiment, a configuration using vertically oriented polyimide will be described. The orientation is preferably a vertical orientation in the initial state. As the liquid crystal, a liquid crystal having a negative dielectric anisotropy, particularly a fluorine-based liquid crystal was used. Further, a positive photoresist was used as a material for the bank-like member.

  FIG. 11 is a schematic diagram showing a configuration of a light source (lamp) used in the alignment process of the present embodiment, where (a) is a cross-sectional view along the longitudinal direction of the lamp, and (b) is along the short side direction of the lamp. FIG. As the lamp 121, a low-pressure mercury lamp manufactured by USHIO INC. Was used. As shown in FIG. 11B, a shielding plate is provided so that direct light does not reach the irradiated object between the tube-shaped ultraviolet light emitting tube as the lamp 121 and the surface of the alignment film 103 as the irradiated object. 122 is provided, and a so-called cold mirror 123 that does not reflect infrared rays is provided on the back surface. In this lamp configuration, as shown in FIG. 11A, ultraviolet rays are randomly irradiated in the longitudinal direction of the lamp 121, whereas in the short direction of the lamp 121, the lamp 121 is almost perpendicular to the optical mask 102. Ultraviolet rays are irradiated.

  In this case, as shown in FIG. 11A, the slit 111 of the optical mask 2 and the lamp 121 were set to be orthogonal to each other. As a result, the alignment film 103 is obliquely irradiated with light from the slit 111 so as to leak in the lateral direction of the slit 111. Then, as shown in FIG. 12, scanning was performed while keeping the lamp 121 perpendicular to the slit 111 so that the entire alignment film 3 was uniformly irradiated with scattered light. Of course, it is not necessary to be limited to this configuration, and the installation direction of the lamp 121 can be changed by 90 degrees, and the shielding plate 122 provided immediately below the lamp 121 is removed, and scattered light is directly emitted from the lamp 121. It is also possible to positively use ultraviolet rays directed toward the surface of the alignment film 103 while irradiating. However, the combination of the shielding plate 122 and the cold mirror 123 according to this embodiment may cause light to be irradiated in a direction different from the direction in which the liquid crystal molecules are originally intended to be tilted, that is, the direction perpendicular to the direction in which the slit 111 extends. The orientation becomes smaller and more stable and reliable.

  The light that wraps around from the slit 111 may be either non-polarized light or polarized light, but it is possible to use non-polarized light when a vertically aligned alignment film is used. As a method of irradiating light, proximity exposure is performed because light is circulated and irradiated. Here, the distance between the optical mask 102 and the alignment film 103 is preferably about several μm to 100 μm. If it is out of this range, there is a possibility that adverse effects such as insufficient light wrapping and inability to obtain the alignment or difficulty in defining the boundary of the divided alignment.

  In addition, the width of the slit 111 of the optical mask 102 is preferably about several μm to 100 μm. If it is out of this range, similarly, the light wraps around insufficiently, and there is a possibility that bad effects such as alignment failure and difficulty in defining the boundary of divided alignment may occur.

  Hereinafter, various examples in which the divided alignment of the present embodiment is applied to a TFT-LCD will be described.

  13A and 13B are schematic views showing an example in which the TFT-LCD is vertically divided into two parts, where FIG. 13A is an enlarged plan view in the vicinity of the pixel electrode, and FIG. 13B is a cross-sectional view during the alignment process on the CF substrate side. c) is a cross-sectional view at the time of alignment processing on the TFT substrate side. In FIG. 13B, the slit 111 is arranged in parallel with the gate electrode 113 and along the vicinity of the gate electrode 113 so that the CF substrate 104b is irradiated with ultraviolet rays. Irradiating. In FIG. 13C, the slit is arranged in parallel with the storage capacitor (Cs) electrode 117 (gate electrode 113) and at a position coincident with the Cs electrode 117, and the TFT substrate 104a is irradiated with ultraviolet rays. 13A and 13B, the scattered light is irradiated so that the liquid crystal molecules are inclined in the direction from the gate electrode 113 of the TFT substrate 104a toward the vertical center of the pixel electrode 118 of the CF substrate 104b.

  In addition to this light irradiation, it is possible to provide a bank-like member 116, and it is effective to provide the CF substrate 104b near the center of the pixel electrode 118 in parallel with the gate electrode 113 (CS electrode 117). . In addition to the light irradiation, it is effective to provide the bank-like member 116 in parallel with the gate electrode 113 (Cs electrode 117) at a position substantially coincident with the gate electrode 113 on the TFT substrate 104a side.

  14A and 14B are schematic views showing an example in which the TFT-LCD is divided into two parts on the right and left sides. FIG. 14A is an enlarged plan view in the vicinity of the pixel electrode, and FIG. 14B is a cross-sectional view during the alignment process on the CF substrate side. c) is a cross-sectional view at the time of alignment processing on the TFT substrate side. On the CF substrate 104a side, the ultraviolet irradiation slit 111 is arranged substantially in line with the position of the data electrode 115 to irradiate the ultraviolet light. On the TFT substrate 104b side, the slit 111 is set in the center of the left and right of the pixel electrode 118 in parallel with the data electrode 115 to irradiate scattered light. Thereby, the liquid crystal molecules are aligned so as to be inclined from the data electrode 115 on the TFT substrate 104b side toward the left and right center portion of the pixel electrode 118 of the CF substrate 104b. This coincides with the alignment direction due to the oblique leakage electric field from the data electrode 115. Here, it is effective to form the bank-like member 116 in consideration of stabilizing the orientation, in particular, fixing the position of occurrence of disclination at the boundary portion of the orientation.

  In this case, it is effective to form the bank-like member 116 so as to run up and down the center of the pixel electrode 118 on the CF substrate 104a side, and on the TFT substrate 104b side, the data is located at a position almost coincident with the data electrode 115. It is effective to form the bank-like member 116 in parallel with the electrode 115.

  FIGS. 15 and 16 are schematic views showing an example in which the TFT-LCD is vertically divided into four parts vertically and horizontally, (a) is an enlarged plan view in the vicinity of the pixel electrode, and (b) is an alignment process along the data electrode. (C) is sectional drawing at the time of the alignment process along a gate electrode.

  In both FIGS. 15 and 16, the liquid crystal molecules are inclined so that the liquid crystal molecules are tilted from the four corners of the pixel electrode 118 of the TFT substrate 104b toward the center of the pixel electrode 118 when the CF substrate 104a is placed in front of the paper surface. The orientation direction is realized. On the pixel electrode 118, the alignment is divided into four parts vertically and horizontally. In the upper right region, the liquid crystal molecules are averaged so as to fall from northeast to southwest. Similarly, the inclination of the liquid crystal molecules is southeast in the lower right. From northwest to northwest, it is oriented so that it falls from northwest to southeast.

  In tilting the liquid crystal molecules at 45 degrees, the orientation on the CF substrate 104a side and the orientation on the TFT substrate 104b side are set to the true direction of the 90 degree direction, and the liquid crystal molecules are directed toward the intermediate direction between these two orientations. Try to fall down. The principle of this orientation direction is disclosed in Digest of AM-LCD 98, for example. Here, when the liquid crystal molecules are inclined from northeast to southwest, (1) a method of performing an alignment process so that the TFT substrate 104b side is tilted southward, and a process of tilting the CF substrate 104a side westward; 2) Two methods are conceivable: an alignment process so that the TFT substrate 104b side is tilted westward, and an alignment process is performed so that the CF substrate 104a side is tilted southward.

  FIG. 15 shows an alignment process by the method shown in (1). On the TFT substrate 104b side, a slit of an optical mask for ultraviolet irradiation is provided in the vicinity of the CS electrode 117 in parallel with the Cs electrode 117 to irradiate scattered light (FIG. 15B). On the CF substrate 104a side, a slit of an optical mask for ultraviolet irradiation is provided in the vicinity of the data electrode 115 in parallel with the data electrode 115 to irradiate scattered light (FIG. 15C). Furthermore, it is effective to provide the bank-like member 116 on both the TFT substrate 104b and the CF substrate 104a. On the TFT substrate 104b side, the bank-like member 16 is formed in the vicinity of the data electrode 115 and the gate electrode 113 so as to be parallel to the data electrode 115 and the gate electrode 113, respectively. This has the function of helping the liquid crystal to be divided into four parts. On the CF substrate 104a side, the bank-like member 116 is formed so as to extend vertically and horizontally from the center of the pixel electrode 118. As described above, the bank-like member functions to help determine the boundary of the orientation division.

  FIG. 16 shows an alignment process by the method shown in (2). On the CF substrate 104a side, a slit of an optical mask for ultraviolet irradiation is provided in the vicinity of the gate electrode 113 in parallel with the gate electrode 113 to irradiate scattered light (FIG. 16B). On the TFT substrate 104b side, a slit of an optical mask for ultraviolet irradiation is provided in the vicinity of the center of the pixel electrode 18 in parallel with the data electrode 115 to irradiate scattered light (FIG. 16C). Further, it is effective to provide the bank-like member 116 on both the TFT substrate 104b and the CF substrate 104a. On the TFT substrate 104 b side, a bank-like member 116 is formed in the vicinity of the data electrode 115 and the gate electrode 113 in parallel with each of the data electrode 115 and the gate electrode 113. This has the function of helping the liquid crystal to be divided into four parts. Further, on the CF substrate 104a side, the bank-like member 116 is formed so as to extend from the center of the pixel electrode 118 in the vertical and horizontal directions.

  Here, as the surface energy of the alignment film in the pixels of the alignment-divided liquid crystal display device, the surface energy at the division boundary becomes the maximum and becomes the lowest at the part away from the boundary. This is because the amount of UV irradiation itself varies within a pixel. The area directly below the slit is the boundary of the division, but the surface energy is maximized because this part is irradiated with the most ultraviolet rays, and since the leaked light is only irradiated to the part far from the boundary, the absolute amount irradiated with ultraviolet rays is Small surface energy does not increase.

  FIG. 17 is a schematic diagram of a configuration in which, when the TFT-LCD is vertically divided into two, the disorder of alignment due to the horizontal electric field from the data electrode is suppressed by a bank-like member provided on the CF substrate side. An enlarged plan view of the vicinity of the electrode, (b) is a cross-sectional view during alignment processing along the data electrode (along line segment CD), and (c) is along the gate electrode (along line segment AB). I) A cross-sectional view of the alignment treatment.

  As shown in FIG. 17A, on the CF substrate 104a side, a bank-like member 116 is formed in parallel to the data electrode 15 at the center left and right direction of the pixel electrode 18 and the portion facing the data electrode 15. The effect of the bank-like member 116 provided in parallel with the data electrode 115 will be described with reference to FIG. The liquid crystal molecules in the vicinity of the data electrode 115 try to align so as to fall toward the center of the pixel due to the electric field from the data electrode 115. On the other hand, the bank-like member 116 provided on the opposing CF substrate 104a functions to incline liquid crystal molecules in a direction away from the pixel electrode 118 due to the effect of the slope. These effects cancel each other, so that the liquid crystal molecules are uniformly directed vertically without falling toward the center of the pixel.

  Further, in this case, as shown in FIG. 18, the end of the bank-like member 116 facing the data electrode 115 is formed so as to partially overlap the end of the pixel electrode 118 of the TFT substrate 104b. FIG. 19 shows the relationship between the width of the overlapping portion 116a and the width of alignment failure at the end of the pixel electrode 118. Thus, by making the width of the overlapping portion 116a 1 μm or more, preferably 2 μm or more, it is possible to suppress the occurrence of alignment failure. Therefore, when the overlap portion 116a is actually formed, it is considered that a misalignment of about 3 μm is ensured and the width of the overlap portion 116a is surely obtained to be 1 μm or more, so that the function of the pixel electrode or the like is not impaired. Is set to 1 μm (lower limit of necessary width) +3 μm (misalignment) to 5 μm (upper limit of necessary width) +3 μm (misalignment) = 4 μm to 8 μm, 5 μm to 8 μm. Thereby, it is possible to sufficiently prevent the occurrence of alignment failure.

  Up to this point, the configuration in which the bank-like member 16 is formed on the CF substrate 104a or the TFT substrate 104b has been described. However, instead of these bank-like members 116, the pixel electrode 118 has a slit-like omission having no electrode portion. Even if it forms, the same effect can be acquired. A specific example is shown in FIG. Here, FIG. 13A corresponds to FIG. 13A, and a slit-like omission 131 is formed at a position parallel to the Cs electrode 117 (gate electrode 113) of the pixel electrode 118 and coincident with the Cs electrode 117. (B) corresponds to FIG. 14 (a), and when a slit-like omission 131 is formed in the pixel electrode 118 at a position parallel to the data electrode 115 and corresponding to the central portion of the pixel electrode 118, (c) Corresponds to FIG. 15A, and shows a case where a slit-like drop 131 is formed in a cross shape on the pixel electrode 118, respectively.

  FIG. 21 is a characteristic diagram showing the examination results of the optimum value of the slit width of the optical mask and the distance (distance A) between the optical mask and the substrate in which the alignment state is good. Good alignment can be realized when the slit width is 3 μm to 100 μm and the distance between the mask and the substrate is 3 μm to 100 μm. Furthermore, the distance between the optical mask and the substrate is preferably about 50 μm to 100 μm, and the slit width and the distance A are almost equal, or the slit width is set to a range from about the same as the distance A to about 1/20. Good orientation can be achieved.

  As described above, according to the present embodiment, a vertical alignment type liquid crystal display device with a small number of disclination lines of two-part or four-part orientation by accurately performing an alignment process using ultraviolet rays with a minimum number of steps. As a result, it is possible to realize a bright screen that is comparable to the case where the TN mode is used. In addition, as a response speed, it is possible to realize a high-speed response similar to or higher than that of a so-called MVA type liquid crystal display device provided with many bank-like members.

(Third embodiment)
In the present embodiment, an alignment processing apparatus and method used when performing division alignment on an alignment film that is a constituent element of a liquid crystal display device will be exemplified. Also in this embodiment, the alignment film is the same as that of the second embodiment, that is, composed of two kinds of polymers, and the pretilt angle starts to change from the vertical alignment by the irradiation of ultraviolet rays, and the pretilt angle exceeds a certain ultraviolet irradiation amount. It is preferable to use one having a constant value near 90 °, or one having a characteristic that the pretilt angle starts to change from vertical alignment by irradiation with ultraviolet rays and returns to vertical alignment again by irradiation with ultraviolet rays.

  FIG. 22 is a schematic cross-sectional view showing the main configuration of the alignment processing apparatus of the present embodiment. Quartz glass having a property of transmitting a short wavelength region (for example, 254 nm) of the outer line is used as the material of the optical mask 201. A mask pattern made of metallic chrome is formed on one surface of the optical mask 201. The master pattern is formed by providing striped slits 211 in metallic chrome. The stripe-shaped slits 211 are arranged at the same pitch as the pitch of the pixels for alignment division. For example, when the pixel pitch is 200 μm, the width of the slit 211 is 10 μm, and the width of the metal chrome pattern from the slit 211 to the adjacent slit 211 is 190 μm.

  On the light source side surface of the optical mask 201, a scattering mechanism 221 that uses parallel light as scattered light is formed. Specifically, the surface on the light source side is sandblasted to form a ground glass.

  Next, the alignment film 203 on the glass substrate 202 is irradiated with ultraviolet rays. When irradiating the TFT substrate 204b with ultraviolet rays, the optical mask 201 is arranged so that the positions of the stripe-shaped slits 211 substantially coincide with the left and right center positions of the pixels in parallel with the data electrodes.

  On the other hand, the optical mask 201 is arranged in the case where the counter substrate (CF substrate) 204a is irradiated with ultraviolet light, the stripe-shaped slit 211 is positioned at the data electrode position of the TFT substrate 204b in the counter substrate 204a. Arranged in a direction parallel to the electrodes.

  After the optical mask 201 is arranged as described above, ultraviolet rays of parallel light are irradiated perpendicularly to the light source side surface of the optical mask 201. The irradiated ultraviolet rays are scattered in the ground glass portion, and are distributed and irradiated in two directions from the slit 211 to the center as shown in the figure.

  When the TFT substrate 204b and the counter substrate 204a are bonded together, the positions of the mutual slit portions come to the center of the pitch where the slits are arranged. As a result, a region that is inclined and oriented in a direction perpendicular to the slit is formed between the slit on the TFT substrate 204b side and the slit on the counter substrate 204a side, that is, with a width of 90 μm. By using the slit position at the center of the pixel as a boundary and tilting in opposite directions to each other, it is possible to realize alignment division in two directions within one pixel.

  FIG. 23 is a schematic cross-sectional view showing another example of the present embodiment. Here, as a method for realizing the scattering function 221, the portion to be subjected to the sandblasting described above is formed only in the portion where the slit 211 on the side where the master pattern of the optical mask 201 is open, thereby forming a ground glass shape.

  The arrangement of the optical mask 201 is the same as described above, and parallel light ultraviolet rays are irradiated perpendicularly to the surface of the optical mask 201 on the light source side. The irradiated ultraviolet rays are scattered in the ground glass-like portion, and when scattered light is emitted from the slit 211 portion as shown in the drawing, it is dispersed in two directions with the central portion as a boundary, and is irradiated onto the alignment film 203. The

  When the TFT substrate 204b and the counter substrate 204a are bonded to each other, the positions of the mutual slit portions correspond to the central portion of the pitch where the slits are arranged. As a result, a region that is inclined and oriented in a direction perpendicular to the slit is formed between the slit on the TFT substrate 204b side and the slit on the counter substrate 204a side, that is, with a width of 90 μm. By performing tilt alignment in opposite directions with the slit position at the center of the pixel as a boundary, it is possible to realize alignment division in two directions within one pixel.

  FIG. 24 is a schematic cross-sectional view showing still another example of the present embodiment. A prism 212 having an isosceles triangular cross-sectional shape with the opening width of the slit as a base is provided at the opening of the slit 211 of the optical mask 201 described above. The arrangement of the optical mask 201 is the same as described above, and parallel light ultraviolet rays are irradiated perpendicularly to the surface of the optical mask 201 on the light source side. The irradiated ultraviolet rays are reflected and refracted by the prism 212 portion, and when scattered light is emitted from the prism 212 portion as shown, it is divided as parallel light in two directions and irradiated onto the alignment film 203. Is done.

  When the TFT substrate 204b and the counter substrate 204a are bonded to each other, the positions of the mutual slit portions correspond to the central portion of the pitch where the slits are arranged. As a result, a region that is inclined and oriented in a direction perpendicular to the slit is formed between the slit on the TFT substrate 204b side and the slit on the counter substrate 204a side, that is, with a width of 90 μm. With the slit position at the center of the pixel as a boundary, it is possible to realize alignment division in two directions within one pixel by tilting in opposite directions.

  In the present embodiment, even when the ultraviolet light applied to the light source side surface of the optical mask 201 is the scattered light, the ultraviolet light applied to the alignment film 203 is the same as when the parallel light is applied. Dispersed in two directions, a desired alignment division can be realized. By this method, the ultraviolet rays irradiated on the alignment film 203 immediately below the slit are dispersed, and the ultraviolet ray exposure amount in this portion will not be excessive, and one substrate is exposed once. Thus, alignment division can be realized.

  As described above, according to the present embodiment, even when the ultraviolet rays with respect to the optical mask 201 are parallel light, the ultraviolet rays are dispersed or reflected / refracted in the ground glass portion or the prism 212 portion of the optical mask 201. By doing so, the same effect as that obtained when the optical mask 201 is irradiated with ultraviolet rays of scattered light can be obtained. This indicates that an ultraviolet exposure device that emits parallel light can be used as a light source.

  Moreover, since the ultraviolet rays in the portion of the alignment film 203 corresponding to the opening portion of the slit 211 can be dispersed, excessive exposure of this portion can be prevented, and white spots due to tilt reduction of this portion and flow alignment can be prevented. Is possible.

(Fourth embodiment)
In the present embodiment, an alignment processing apparatus and method used when performing division alignment on an alignment film that is a constituent element of a liquid crystal display device will be exemplified. Also in this embodiment, the alignment film is the same as that of the second embodiment, that is, composed of two kinds of polymers, and the pretilt angle starts to change from the vertical alignment by the irradiation of ultraviolet rays, and the pretilt angle exceeds a certain ultraviolet irradiation amount. It is preferable to use one having a constant value near 90 °, or one having a characteristic that the pretilt angle starts to change from vertical alignment by irradiation with ultraviolet rays and returns to vertical alignment again by irradiation with ultraviolet rays.

  FIG. 25 is a schematic diagram for explaining the principle of the present embodiment, in which (a) is a schematic cross-sectional view showing the main configuration of the alignment processing apparatus of the present embodiment, and (b) is a liquid crystal display subjected to the alignment processing. It is a schematic sectional drawing which shows the main structures of an apparatus. Quartz glass having the property of transmitting a short wavelength region (for example, 254 nm) of ultraviolet rays is used as the material of the optical mask 301. As shown in FIG. 26, a mask pattern made of metallic chromium is formed on one surface of the optical mask 301. The mask pattern is provided with stripe-shaped alignment regulating slits 211 in metal chrome. The alignment regulating slit 211 is the same as the slit 211 described in the third embodiment, and is used for aligning liquid crystal molecules in a desired direction, and has the same pitch as the pitch of pixels that perform alignment division. It shall be arranged. For example, when the pixel pitch is 200 μm, the width of the slit 211 is 10 μm, and the width of the metal chromium pattern from the slit to the adjacent slit 211 is 190 μm.

  Furthermore, an alignment correction slit 311 is provided on the same optical mask 311. The slits must be narrower than the slits that orient the liquid crystal molecules in the desired direction, and must be arranged in directions perpendicular to each other. The pixel pitch is about one third, 70 μm, and the width of the slit 311 is about 1 μm.

  Next, the alignment film 303 on the glass substrate 304 is irradiated with ultraviolet rays. As shown in FIG. 27, the arrangement of the optical mask 301 when irradiating the TFT substrate 304b with ultraviolet rays is such that the position of the alignment regulating slit 211 substantially coincides with the left and right center positions of the pixels perpendicular to the data electrode 315. To place. The position of the alignment correction slit 311 is arranged in parallel with the data electrode 315 so as to correspond to the center between adjacent pixel electrodes 318, that is, the center of the data electrode 315.

  On the other hand, the optical mask 301 in the case of irradiating the counter substrate 304 a with ultraviolet rays requires only the alignment regulating slit 211. The position of the slit 211 is arranged in the direction perpendicular to the data electrode 315 at the position of the gate electrode 313 of the TFT substrate 304b in the counter substrate 304a.

  After the optical mask 301 is arranged as described above, ultraviolet rays of scattered light are irradiated perpendicularly to the light source side surface of the optical mask 301. The irradiated ultraviolet rays are distributed and irradiated in two directions from the slit portion as shown in FIG.

  That is, in the vicinity of the portion irradiated with the ultraviolet rays by the slit 311, since the scattered light is irradiated in a fan shape with the slit 311 as the center as shown in FIG. 25, the liquid crystal molecules have the slit 311 with respect to the alignment film 303. An orientation regulating force that is inclined in the direction is given. As a result, the direction in which the liquid crystal molecules are oriented by the electric field at the end of the pixel electrode 318 and the orientation regulating force of the orientation film 303 are opposite to each other, thereby canceling out the forces to orient the respective liquid crystals. Thus, it is possible to prevent the tilt of the liquid crystal molecules in the direction perpendicular to the tilt alignment direction of the desired liquid crystal molecules.

  Actually, the image display apparatus (apparatus B) in which only the two-divided orientation restriction is applied to the luminance change in the image display apparatus (apparatus A) that is subjected to the orientation correction in addition to the two-part orientation restriction by the method of the present embodiment. ). As a result, in the device B, the liquid crystal molecules are inclined due to the electric field at the end of the pixel electrode 318 as shown in FIG. 28A, thereby causing the luminance at the end of the black matrix 321 as shown in FIG. Decrease occurs. On the other hand, in the device A, since the inclination of the liquid crystal molecules at the end of the pixel electrode 318 is eliminated as shown in FIG. 29A, at the end of the black matrix 321 as shown in FIG. An extremely good image can be obtained without causing a decrease in luminance.

  When the TFT substrate 304b and the counter substrate 304a are bonded together, the positions of the mutual slit portions come to the center of the pitch where the slits are arranged. As a result, a region that is inclined and oriented in a direction perpendicular to the slit is formed between the slit on the TFT substrate 304b side and the slit 304a on the counter substrate side, that is, with a width of 90 μm. With the slit position at the center of the pixel electrode 318 as a boundary, the two layers can be divided in two directions within one pixel by tilting in opposite directions.

  FIG. 30 is a schematic plan view showing an optical mask in another example of the present embodiment. The process up to the formation of the slit of the optical mask is the same as described above, but a scattering mechanism for incident ultraviolet rays is provided on the surface of the slit 211 that aligns liquid crystal molecules in a desired direction on the side facing the alignment film 303. Specific examples of the scattering mechanism include sandblasting only the opening of the slit 211 to form a ground glass-like portion 211a, or irradiating a laser pulse to provide a groove having a hollow cross section. Conceivable.

  The irradiated ultraviolet rays are scattered in the ground glass-like portion 211a, and the width of irradiation in the alignment correction slit 211 is thereby narrowed, so that the original alignment direction of the liquid crystal molecules is not adversely affected.

  FIG. 31 is a schematic plan view showing an optical mask in still another example of the present embodiment. Here, only the portion of the alignment correction slit 311 in the optical mask 301 is formed to have a predetermined height, for example, about 50 μm. As a result, the distance between the optical mask 301 and the alignment film 304 facing each other is reduced by about 50 μm only at the portion of the alignment correction slit 311, and the width of scattering of the incident ultraviolet rays only at this portion can be reduced. This does not adversely affect the original alignment direction of the liquid crystal molecules.

  FIG. 32 is a schematic diagram showing an example of a light source used in still another example of the present embodiment ((a) is a short direction and (b) is a long direction), and FIG. It is a schematic plan view which shows the relationship with the slit of a mask. Here, a method of changing the direction of the light source 302 is adopted. For example, a tube-shaped light source 302 that irradiates ultraviolet rays is as shown in the figure, and has a property that the long side direction has a higher scattering property than the short side direction of the light source 302. In this embodiment, this property is used. Specifically, the method is as follows.

  Arrangement is made so that the long side direction of the ultraviolet light source 302 is positioned parallel to the direction of the alignment correction slit 311 of the optical mask 301. As a result, the ultraviolet light passing through the alignment correction slit 311 has a narrower scattering width, and conversely has a positional relationship perpendicular to the long side direction of the light source 302. Ultraviolet light that has passed through the slit 211 for aligning liquid crystal molecules in a desired direction has a wide scattering width. This does not adversely affect the original alignment direction of the liquid crystal molecules.

  As described above, according to the present embodiment, since the alignment regulating force at the end of the pixel electrode 318 and the direction of the force to be aligned by the electric field cancel each other, the tilt alignment direction of the desired liquid crystal molecules Thus, it is possible to prevent the tilt of the liquid crystal molecules in the vertical direction, thereby preventing the occurrence of disclination and suppressing the decrease in luminance at the pixel end.

  On the other hand, since it is not necessary to newly form a bank-like member, it is possible to simplify the process of providing the alignment regulation by forming the alignment regulation slit 311 together with the orientation correction slit 211 in the optical mask 301. .

  (Fifth Embodiment) In this embodiment, a liquid crystal display device characterized by pixel electrodes is exemplified. Also in this embodiment, the alignment film is the same as that of the second embodiment, that is, composed of two kinds of polymers, and the pretilt angle starts to change from the vertical alignment by the irradiation of ultraviolet rays, and the pretilt angle exceeds a certain ultraviolet irradiation amount. It is preferable to use one having a constant value near 90 °, or one having a characteristic that the pretilt angle starts to change from vertical alignment by irradiation with ultraviolet rays and returns to vertical alignment again by irradiation with ultraviolet rays.

  FIG. 34 is a schematic plan view showing the vicinity of the pixel electrode of the liquid crystal display device of the present embodiment. A slit 411 is provided in the vicinity of the data electrode 415 of the pixel electrode 418 in order to prevent alignment failure caused by a lateral electric field from the data electrode 415. The slit 411 extends in a direction parallel to the data electrode 415 (a direction orthogonal to the gate electrode 413). The width of the slit 411 is effectively in the range of 2 μm to 5 μm. In particular, it was confirmed that the effect of suppressing the alignment failure was greatest when the slit having a width of 3 μm was used.

  Thus, by providing the thin slit 411 in the pixel electrode 418, the liquid crystal molecules have a characteristic that the liquid crystal molecules tend to fall in a direction parallel to the slit 411. In this embodiment, this action is used in combination with the photo-alignment. Originally, when the gap portion exists in the pixel electrode, the electric field is inclined, so that the liquid crystal is inclined in the direction away from the gap (FIG. 35A). reference). However, when a thin slit, for example, a slit 411 having a width of 3 μm, is provided, the liquid crystal molecules try to tilt on both sides of the slit 411, and the orientation is lost so that it eventually tilts in the slit direction (FIG. 35 ( b)). Here, when the slit 411 is provided as shown in FIG. 34, the tilt of the liquid crystal molecules is lost due to the slit portion (similar to FIG. 35B) and eventually tilted in the direction parallel to the slit 411. Thus, poor alignment due to the data electrode is suppressed.

  FIG. 36 is a schematic view showing another example of the present embodiment, in which (a) is a plan view in the vicinity of a pixel electrode, and (b) is a cross-sectional view. Here, a plurality of slits 411 are provided throughout the pixel electrode 418. Thereby, the stability of orientation becomes more reliable. In addition, it is important that these slits 411 are connected by a central connection portion 421 of the pixel electrode 418. That is, considering the relationship between the connection portion 421 and the slit 411, the electric field in the connection portion 421 is as shown in FIG. 34B, and the electric field spreads out from the connection portion 421 in a fan shape. This effect causes the liquid crystal molecules to tilt in a more preferred direction.

  As described above, according to the present embodiment, it is possible to realize a liquid crystal display device with no alignment failure and a wide viewing angle.

  Hereinafter, various aspects of the present invention will be collectively described as supplementary notes.

  (Supplementary note 1) A liquid crystal display device comprising a pair of substrates that face each other with an alignment film facing each other and maintained at a predetermined interval, and in which a liquid crystal layer is inserted between the alignment films, wherein the alignment film includes the liquid crystal layer A liquid crystal display device comprising a material including at least two kinds of polymers having a predetermined initial alignment property with respect to liquid crystal molecules and having different pretilt angle change rates according to ultraviolet irradiation.

  (Supplementary note 2) The liquid crystal display device according to supplementary note 1, wherein the alignment film is made of a material containing a mixture of the respective polymers.

  (Supplementary note 3) The liquid crystal display device according to supplementary note 1, wherein the alignment film is made of a material containing a copolymer of each polymer.

  (Appendix 4) One of the two types of polymers described above is one that changes the orientation of the liquid crystal molecules from the initial state, and the other maintains the orientation of the liquid crystal molecules in the initial state. The liquid crystal display device described.

  (Supplementary note 5) The liquid crystal display device according to supplementary note 4, wherein the initial state is vertical alignment, and the alignment by the one polymer is horizontal alignment.

  (Appendix 6) An alignment film is formed on each of a pair of substrates, a liquid crystal layer is inserted between the alignment films so that the alignment films face each other, and a liquid crystal display device is manufactured by keeping the distance between the substrates constant. The alignment film is made of a material including at least two types of polymers having initial alignment with respect to liquid crystal molecules of the liquid crystal layer and having different pretilt angles depending on ultraviolet irradiation. A method of manufacturing a liquid crystal display device, comprising: applying to a surface of the alignment film, irradiating ultraviolet rays from an oblique direction to a surface of the alignment film, and realizing a desired alignment with respect to liquid crystal molecules of the liquid crystal layer.

  (Supplementary note 7) A liquid crystal display device comprising a pair of substrates each having an alignment film facing each other and maintained at a predetermined interval, wherein a liquid crystal layer is inserted between the alignment films, wherein the alignment film includes the liquid crystal layer Made of a material containing at least two kinds of polymers having a predetermined initial orientation with respect to liquid crystal molecules and having different rates of change in surface energy in response to ultraviolet irradiation, and adjusted to a predetermined surface energy by ultraviolet irradiation on the alignment film. A liquid crystal display device.

(Supplementary note 8) The liquid crystal display device according to supplementary note 7, wherein the alignment film is made of a material including a mixture of the polymers or a copolymer of the polymers.

  (Supplementary note 9) The method for manufacturing a liquid crystal display device according to supplementary note 8, wherein an initial alignment state of the alignment film is a vertical alignment.

  (Appendix 10) Of the at least two types of polymers, at least one of the polymers is easily changed in alignment from the initial state by irradiation with ultraviolet rays, and at least one of the other polymers is difficult to change in alignment from the initial state by irradiation with ultraviolet rays. The manufacturing method of a liquid crystal display device according to appendix 8, wherein:

  (Appendix 11) An alignment treatment apparatus for irradiating an alignment film with ultraviolet rays and aligning liquid crystals provided on the alignment film, wherein a light source for irradiating ultraviolet scattered light, and a slit formed in the light source. The optical mask is disposed above the alignment film, and the diffused light spreading around the slit is generated by irradiating the optical mask with scattered light from the light source, and the diffusion An alignment processing apparatus characterized by irradiating the alignment film with light and causing the liquid crystal to have a divided alignment depending on a diffusion direction of diffused light.

  (Additional remark 12) The said optical mask is an alignment processing apparatus of Additional remark 11 characterized by the said slit being formed in stripe form.

  (Additional remark 13) The said optical mask is arrange | positioned so that the said slit may be located in the site | part substantially parallel to this in the vicinity of the data electrode formed in the lower part of the said alignment film, The additional remark 11 characterized by the above-mentioned. Orientation processing equipment.

  (Additional remark 14) The said optical mask is arrange | positioned so that the said slit may be located in the site | part which substantially corresponds to the data center formed in the lower part of the said alignment film, and the horizontal center position of a pixel. The alignment processing apparatus according to appendix 11.

  (Additional remark 15) The said optical mask is arrange | positioned so that the said slit may be located in the site | part substantially parallel to this in the vicinity of the gate electrode formed in the lower part of the said alignment film, The additional remark 11 characterized by the above-mentioned. Orientation processing equipment.

  (Supplementary Note 16) The optical mask is characterized in that the slit is disposed so as to be substantially parallel to a gate electrode formed in a lower part of the alignment film and at a position substantially coincident with a vertical center position of a pixel. The alignment processing apparatus according to appendix 11.

  (Supplementary note 17) The alignment processing apparatus according to supplementary note 11, wherein the light source is a tube-shaped lamp.

  (Supplementary note 18) The alignment process according to supplementary note 17, wherein the optical mask and the light source are arranged so that a longitudinal direction of the slit of the optical mask and a longitudinal direction of the light source are parallel or orthogonal to each other. apparatus.

  (Supplementary Note 19) A cold mirror that absorbs infrared rays is provided so as to cover the back of the light source, and the reflected light from the cold mirror is scattered as light within the plane along the longitudinal direction of the light source. The alignment processing apparatus according to appendix 17, wherein the alignment film is irradiated as parallel light in a plane orthogonal to the longitudinal direction of the light source.

  (Supplementary note 20) A liquid crystal display device comprising a pair of substrates each having an alignment film opposed to each other and maintained at a predetermined interval, wherein a liquid crystal layer is inserted between the alignment films, and a plurality of liquid crystals are provided at predetermined boundaries on the liquid crystal. The liquid crystal display device is characterized in that a surface energy of the alignment film has a maximum value or a minimum value at a boundary of the alignment division and decreases or increases as the distance from the boundary increases.

  (Appendix 21) The alignment film is made of a material having a predetermined initial alignment property with respect to liquid crystal molecules of the liquid crystal and containing at least two kinds of polymers having different pretilt angle change rates in response to ultraviolet irradiation. Item 20. The liquid crystal display device according to appendix 20, wherein

  (Additional remark 22) The alignment film has a pretilt angle that starts to change from vertical alignment due to ultraviolet irradiation, and the pretilt angle becomes a constant value near 90 ° when a certain ultraviolet irradiation amount is exceeded. 22. A liquid crystal display device according to item 21.

  (Supplementary note 23) The supplementary note 20 is characterized in that the alignment film has a characteristic that the pretilt angle starts to change from the vertical alignment by irradiation of ultraviolet rays and returns to the vertical alignment again by irradiation of ultraviolet rays. Liquid crystal display device.

  (Supplementary Note 24) An alignment treatment method for irradiating an alignment film with ultraviolet rays and aligning a liquid crystal provided on the alignment film, wherein an optical mask provided with a slit is disposed above the alignment film, and ultraviolet light is scattered. By irradiating the optical mask with scattered light from a light source that irradiates light, diffused light that spreads around the slit is generated, and the diffused light is applied to the alignment film to diffuse the diffused light to the liquid crystal. An alignment treatment method characterized by causing a divided alignment depending on the orientation.

  (Supplementary Note 25) The alignment film is divided and aligned so as to have different alignments in a plurality of regions of the pixel, and is provided on each of a pair of substrates to form a component of a liquid crystal display device. Additional alignment 24, wherein the number of divisions of the divided alignment in one of the substrates is 2, and the alignment is regulated so that liquid crystal molecules are inclined in opposite directions in the pixel. The orientation treatment method according to 1.

  (Supplementary Note 26) The direction of the alignment division on each substrate is a line segment connecting the pixel center of the substrate facing the gate electrode and / or the data electrode in relation to the gate electrode and / or the data electrode. The orientation treatment method according to appendix 24, wherein the orientation treatment method is a direction.

  (Supplementary note 27) An alignment processing apparatus for irradiating an alignment film with ultraviolet light and aligning liquid crystal provided on the alignment film, the light source for irradiating with ultraviolet light, the light source provided under the light source, and a slit being formed An optical mask having an ultraviolet light scattering mechanism, and the optical mask is disposed above the alignment film, and the optical mask is irradiated with ultraviolet light from the light source to generate diffused light spreading around the slit. The alignment processing apparatus is characterized by irradiating the alignment film with the diffused light and causing the liquid crystal to have a split alignment depending on a diffusion direction of the diffused light.

  (Additional remark 28) The said scattering mechanism is a scattering means formed in the surface by the side of the said light source of the said optical mask, The orientation processing apparatus of Additional remark 27 characterized by the above-mentioned.

  (Additional remark 29) The said scattering mechanism is a scattering means formed in the opening part of the said slit of the said optical mask, The orientation processing apparatus of Additional remark 27 characterized by the above-mentioned.

  (Supplementary note 30) The alignment processing apparatus according to supplementary note 27, wherein the optical mask has the slit formed in a stripe shape.

  (Supplementary Note 31) When the optical mask is disposed above the alignment film, the slit is substantially parallel to the data electrode formed below the alignment film and substantially coincides with the left and right center positions of the pixels. 28. The alignment processing apparatus according to appendix 27, wherein the alignment processing apparatus is positioned so as to be positioned at the position.

  (Supplementary Note 32) When the optical mask is disposed above the alignment film, the slit is substantially parallel to the gate electrode formed below the alignment film and substantially coincides with the vertical center position of the pixel. 28. The alignment processing apparatus according to appendix 27, wherein the alignment processing apparatus is positioned so as to be positioned at the position.

  (Supplementary note 33) An alignment treatment method for irradiating an alignment film with ultraviolet rays and aligning liquid crystals provided on the alignment film, wherein an optical mask having a UV light scattering mechanism is formed above the alignment film. And irradiating the optical mask with ultraviolet rays from a light source to generate diffused light spreading around the slit, irradiating the diffused light onto the alignment film, and diffusing the diffused light onto the liquid crystal in the diffusion direction An alignment treatment method characterized by causing dependent divided alignment.

  (Supplementary Note 34) A liquid crystal display device comprising a pair of substrates each having an alignment film facing each other and maintained at a predetermined interval, and a liquid crystal layer inserted between the alignment films, wherein a pixel electrode is provided on one of the substrates A liquid crystal display device, characterized in that the liquid crystal molecules formed in a portion corresponding to the end portion of the pixel electrode are given an alignment regulating force in a direction to cancel the alignment due to the electric field generated at the end portion. .

  (Supplementary Note 35) The liquid crystal display device according to claim 34, wherein the liquid crystal layer is subjected to a predetermined division alignment on the pixel electrode according to an alignment regulation of the alignment film.

  (Supplementary Note 36) When manufacturing a liquid crystal display device including a pair of substrates each having an alignment film facing each other and kept at a predetermined interval, and having a liquid crystal layer inserted between the alignment films, the liquid crystal display device is formed on one of the substrates. A method of manufacturing a liquid crystal display device, wherein an alignment regulating force is applied to liquid crystal molecules in a portion corresponding to an end portion of the pixel electrode in a direction to cancel alignment due to an electric field generated at the end portion.

  (Supplementary Note 37) An optical mask in which a slit is formed is arranged on the alignment film so that the slit is parallel to the gate electrode or the data electrode, and the optical mask is irradiated with ultraviolet rays from above. Thus, diffused light spreading around the slit is generated, and the alignment light is applied to the alignment film, and the alignment regulating force is directed toward canceling the alignment due to the electric field generated at the end of the pixel electrode. 37. A method of manufacturing a liquid crystal display device according to appendix 36, wherein:

  (Supplementary note 38) A liquid crystal display device comprising a pair of substrates each having an alignment film facing each other and kept at a predetermined interval, and having a liquid crystal layer inserted between the alignment films, wherein one of the substrates has a pixel electrode And a bus line formed between the pixel electrodes, and a slit substantially parallel to the bus line is formed near the bus line of the pixel electrode.

  (Supplementary note 39) The slit of the pixel electrode gives the liquid crystal molecules in a portion corresponding to the end of the pixel electrode an alignment regulating force in a direction to cancel the alignment due to the electric field generated at the end. 39. A liquid crystal display device according to appendix 38.

  (Supplementary note 40) The liquid crystal display device according to supplementary note 38, wherein at least two slits are formed in the pixel electrode.

  (Supplementary note 41) The liquid crystal display device according to supplementary note 38, wherein a plurality of the slits are formed on the entire surface of the pixel electrode.

  (Supplementary note 42) The liquid crystal display device according to supplementary note 41, wherein each slit is interrupted at a central portion of the pixel electrode to form a region connected as an electrode.

DESCRIPTION OF SYMBOLS 11, 12 Transparent glass substrate 13, 112 Liquid crystal layer 14 Insulating layer 15 Pixel electrode 16a, 16b Alignment film 17 Color filter 18 Common electrode 19, 20 Polarizer 31, 101, 302 Light source 32 Mirror 33 Holder 102, 201, 301 Optical mask 103, 203, 303 Alignment film 104 Substrate 104a, 204a, 304a CF substrate 104b, 204b, 304b TFT substrate 111, 211, 311, 411 Slit 113, 313 Gate electrode 115, 315 Data electrode 116 Bank-like member 117 Cs electrode 118, 318, 418 Pixel electrode 121 Lamp 122 Shield plate 123 Cold mirror 131 Slit opening 211a Frosted glass-like portion 212 Prism 312 Black matrix 421 Connection portion

Claims (1)

In manufacturing a liquid crystal display device comprising a pair of substrates each facing an alignment film and kept at a predetermined interval, and having a liquid crystal layer inserted between the alignment films,
A liquid crystal display device characterized in that an alignment regulating force is applied to a liquid crystal molecule at a portion corresponding to an end portion of a pixel electrode formed on one of the substrates in a direction to cancel alignment due to an electric field generated at the end portion. Production method.

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