JP2002287155A - Liquid crystal display device and manufacturing method thereof - Google Patents

Abstract

(57) [Summary] [PROBLEMS] A liquid crystal display panel can be manufactured with improved yield, excellent productivity, and high reliability. SOLUTION: A step of rubbing the surfaces of the counter substrate and the array substrate in respective predetermined directions to control the alignment at predetermined angles, bonding the counter substrate and the array substrate so as to face each other, and forming a liquid crystal layer in the gap between the substrates. When forming the spacer 5 for regulating the substrate gap on the opposing substrate, the arrangement direction of the adjacent spacers 5r and 5s in the effective screen and the predetermined direction 7 for rubbing are not substantially parallel. The spacer 5 is formed as described above. Thus, the rubbing of the rubbing cloth and the spacer buffer the rubbing cloth during rubbing, and the bristle tip is less likely to be pushed away, so that the bristle tip can sufficiently reach the substrate surface. Therefore, light leakage due to poor non-alignment can be reduced, and the alignment (alignment regulating force) of the substrate surface is stable for a long time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a liquid crystal display device, and more particularly to a method for forming a spacer on a counter substrate and a method for manufacturing the same.

[0002]

2. Description of the Related Art A conventional technique will be described. In a liquid crystal display panel production process, a substrate on which one or more array chips are formed is opposed to a substrate on which a color layer pattern having red, green, and blue optical characteristics and a columnar film spacer are formed so as to face the array chips. An alignment film made of polyimide or the like is applied to the surface of the substrate and heated and cured on two types of substrates, and an alignment process is generally performed on the surface of the alignment film by a rubbing method. The rubbing method here is
A cloth with hair tips of submicron order length is wound around a cylindrical drum, and the entire substrate is moved while rotating the drum at a high speed while maintaining an interval at which the hair tips contact the surface of the alignment film. At this time, the orientation of the drum and the substrate is maintained so as to maintain a specific angle, and the orientation direction is aligned to a specific angle corresponding to the target main viewing angle direction.

After that, a sealing material containing a spacer is applied to one of the two types of substrates,
The two types of substrates are bonded so that the array chip pattern and the pigment film pattern face each other. Then, a single panel is formed by cutting the vicinity of the seal along the seal position, a liquid crystal material is injected into the gap facing the panel, and the injection port is sealed with a sealing material to complete the liquid crystal display panel.

The array chip referred to here is XY
A so-called TFT array chip, in which a signal line group arranged in a matrix and a thin film transistor group electrically connected to the chip are formed. A chip in which a data electrode line group is formed in a matrix arrangement of X and Y with respect to the electrode line group, and signals are sequentially scanned from scanning lines to operate a liquid crystal.
Type array chip. The counter electrode pattern forms a pair with the array chip, and its display screen has a shape similar to that of the array chip.

A general example of the columnar film spacer in the above-mentioned conventional liquid crystal display panel will be described with reference to FIGS. 2, 3, 4 and 5. FIG. 2 and 3 are plan views of a counter substrate which has been put into practical use in recent years. Reference numeral 3 denotes an opening of a black matrix (hereinafter referred to as BM) layer for shading,
A, green 4B and blue 4C are color layer patterns formed in stripes, and 5A and 5B are columnar film spacers, each of which is formed by photolithography. Numeral 6 denotes a pattern forming direction of the columnar film spacer in an oblique direction (a direction substantially close to the rubbing direction), numeral 7 denotes a rubbing direction of the opposing substrate, and directions 6 and 7 substantially coincide with each other. As described above, the hair tips of the cloth come into contact with each other in the direction of 7 and are rubbed. In FIG. 2, the columnar film spacers are evenly arranged on all the colors on the red, green, and blue hue patterns, but in FIG. 3, they are evenly arranged only on the blue hue patterns. When the viewing angle direction is set to the upper or lower viewing direction, the rubbing direction is directed obliquely at 45 degrees as indicated by 7 with respect to the striped color layer pattern as shown in FIGS.

In determining the number of columnar film spacers to be formed, if the number is too large, it is difficult to inject the liquid crystal. On the other hand, if the number is too small, the rigidity of the panel and the uniformity of the gap are lost, so that the optimum density (about 8 pieces / mm ² ) is obtained. Is the main design rule. On the opposite array chip side, it is formed so as to be arranged on the X-direction signal line (not formed at the opening 3 in FIGS. 2 and 3). This is because the vicinity of the columnar film spacer is a non-aligned region that is not sufficiently rubbed, and thus it is necessary to shield light with a BM. As described above, the columnar film spacers are set to have an optimum density according to the panel size (effective screen size) and to have an X within the effective screen according to the number of pixels (resolution such as VGA or XGA).
The direction signal lines are evenly arranged on the upper part. In recent years, due to poor visibility of blue, a method has been proposed in which columnar film spacers are formed only on a blue hue pattern so as to make the non-oriented region inconspicuous even if viewed in the opening. Added as an example.

FIGS. 4 and 5 are cross-sectional views of the above-described counter substrate, wherein 1 is a glass substrate, 2 is a BM layer, 4A,
4B and 4C show red, green and blue color layer patterns, respectively. 5C and 5D denote columnar film spacers, the columnar film spacer 5C in FIG. 4 shows a case where an insulating transparent resin different from the color layer is formed, and 5D in FIG. 5 shows a portion of the color layer pattern overlapping. This shows a case where the layers are formed by lamination.

In general, according to the design rules for the arrangement of the columnar film spacers as shown in FIGS. 2 and 3 described above, it is natural that the columnar film spacers are formed above the X-direction signal lines, and the panel size is increased. And an optimal density according to the number of pixels, and are evenly arranged according to the number of pixels. In the conventional design rules, there is no arrangement rule for the rubbing direction. Therefore, as shown in FIGS. 2 and 3, when the directions of 6 and 7 are almost the same or the distance between the columnar film spacers in the 6 directions is short. was there.

[0009]

When the alignment treatment of the surface of the counter substrate is performed, the surface of the alignment film must be rubbed with the hair tips by the rubbing method and the front surface of the substrate must be rubbed uniformly in the same direction as described above. No. However, the tip of the rubbing cloth has a length of about several hundreds of micrometers, and if the columnar film spacers are arranged at small intervals (about 700 micrometers or less) in the direction of the tip of the rubbing cloth, the tips of the rubbing cloth become columnar. The tip of the bristle cannot reach the surface of the substrate sufficiently because it is buffered and pushed away by the film spacer. Therefore, the portion of the pixel portion (the portion 8 in FIG. 6) between the columnar film spacers, which is arranged in the direction of the rubbing bristle tip, does not sufficiently reach the bristle tip of the rubbing cloth and does not sufficiently rub the substrate surface. . As a result,
A part of the corresponding pixel portion became a non-alignment region due to poor orientation (or alignment regulating force), and light leakage due to non-alignment failure occurred in the initial image inspection. Further, this light leakage also occurs due to deterioration due to a reliability test or the like (particularly, a high-temperature operation test), and there is a problem in yield and reliability.

Therefore, an object of the present invention is to reduce the buffer between the columnar film spacers and the tips of the rubbing cloth when the alignment treatment is performed on the opposing substrate on which the columnar film spacers are formed by the rubbing method. It is an object of the present invention to provide a liquid crystal display device capable of manufacturing a liquid crystal display panel with high yield, high productivity, and high reliability by significantly reducing light leakage due to non-alignment failure, and a method for manufacturing the same.

[0011]

According to a first aspect of the present invention, there is provided a liquid crystal display device comprising: an array substrate having one or a plurality of array chips formed on a surface thereof; An opposing substrate, comprising a liquid crystal layer sandwiched in a substrate gap, the alignment control at a predetermined angle by rubbing the surface of the opposing substrate and the surface of the array substrate in a predetermined direction respectively, on the opposing substrate A liquid crystal display device having a spacer for regulating a gap between substrates, wherein a spacer is formed such that a direction in which adjacent spacers are arranged in an effective screen and a predetermined rubbing direction are not substantially parallel to each other. A liquid crystal display device characterized by the above-mentioned.

As described above, in the configuration in which the spacer for regulating the gap between the substrates is formed on the opposing substrate, the arrangement direction of the adjacent spacers in the effective screen and the predetermined rubbing direction are not substantially parallel to each other. Are formed, the tip of the rubbing cloth and the spacer are buffered at the time of rubbing, and the tip of the hair is less likely to be pushed away, and the tip of the rubbing can sufficiently reach the substrate surface. Accordingly, light leakage due to non-alignment failure due to the above-described causes can be reduced, and the alignment (alignment regulating force) of the substrate surface is stabilized for a long time. As a result, a liquid crystal display panel with high yield and high reliability can be manufactured.

According to a second aspect of the present invention, there is provided a method of manufacturing a liquid crystal display device, comprising the steps of: forming a black matrix layer and red, green, and blue color layers on a surface of a counter substrate; Forming an array chip, rubbing the surface of the counter substrate and the surface of the array substrate in respective predetermined directions to control the orientation at predetermined angles, and bonding the counter substrate and the array substrate so as to face each other. Aligning, including the step of sandwiching a liquid crystal layer in the substrate gap, when forming a spacer for regulating the substrate gap on the counter substrate, the arrangement direction of the adjacent spacers in the effective screen and a predetermined rubbing direction. However, a spacer is formed so as not to be substantially parallel.

Normally, according to the design rules for the arrangement of the columnar film spacers, as described above, the arrangement is designed so that the columnar film spacers are arranged at an optimum density according to the panel size and are evenly arranged according to the number of pixels. In the conventional design rules, there is no arrangement rule for the rubbing direction. Therefore, the rubbing direction substantially matches the oblique direction in which the spacers are uniformly arranged, or the matching oblique direction distance between the columnar film spacers is It was particularly short (about 700 microns or less). Therefore, the spacer formation is designed in consideration of the arrangement position at which the adjacent spacers are formed as described above so that they are not arranged substantially in the same direction as the rubbing direction of the opposing substrate. It is necessary to observe the design rule of equal arrangement at the same time).

In the opposing substrate designed in such a manner that the spacer is formed, the tip of the rubbing cloth and the spacer are buffered at the time of rubbing, and the tip of the tip is less likely to be displaced. Can reach enough. Therefore, since the substrate surface is evenly rubbed by rubbing, when a liquid crystal display panel is subsequently manufactured using this counter substrate,
Light leakage due to non-orientation defects due to the above-mentioned causes can be reduced,
In addition, the orientation (alignment regulating force) of the substrate surface is stable for a long time. As a result, a liquid crystal display panel with high yield and high reliability can be manufactured.

According to a third aspect of the present invention, there is provided a method of manufacturing a liquid crystal display device according to the second aspect.
Spacers are used to form the black matrix layer and the red,
A part of the green and blue color layers is overlapped and laminated. in this way,
Spacers are used to form a black matrix layer and red, green,
Since a part of the blue color layer is overlapped and laminated, it can be easily manufactured without increasing the number of manufacturing steps.

According to a fourth aspect of the present invention, there is provided a method of manufacturing a liquid crystal display device according to the second or third aspect, wherein the spacer disposed in a direction substantially the same as the predetermined direction for rubbing in the effective screen is used. The spacer is formed such that the distance between the arrangements is equal to or more than the diagonal distance of one dot. As described above, since the spacers are formed so that the distance between the spacers disposed in the same direction as the predetermined direction of rubbing in the effective screen is equal to or more than the diagonal distance of one dot, the direction is substantially the same as the rubbing direction. The distance between the arrangements of the spacers arranged on the rubbing cloth can be sufficiently increased, and the rubbing cloth's bristle tip and the spacer are buffered during rubbing, and the bristle tip is reduced. As a result, the substrate surface is evenly and sufficiently rubbed, so that the orientation is stabilized.

According to a fifth aspect of the present invention, there is provided a method of manufacturing a liquid crystal display device according to the second or third aspect, wherein the spacer disposed in the same direction as the predetermined direction of rubbing in the effective screen is used. The spacer is formed such that the distance between the arrangements is equal to or greater than the diagonal distance of one pixel. As described above, since the spacer is formed so that the distance between the spacers disposed in the same direction as the predetermined direction of rubbing in the effective screen is equal to or more than the diagonal distance of one pixel,
The distance between the spacers arranged in substantially the same direction as the rubbing direction can be sufficiently set, and during rubbing, the bristle tips of the rubbing cloth and the spacers are buffered and the bristle tips are reduced. As a result, the substrate surface is evenly and sufficiently rubbed, so that the orientation is stabilized.

According to a sixth aspect of the present invention, in the liquid crystal display device manufacturing method according to the second or third aspect, the distance between the spacers disposed in substantially the same direction as the predetermined direction for rubbing in the effective screen is 700 μm or more. The spacer is formed such that As described above, since the spacers are formed so that the distance between the spacers arranged in the same direction as the predetermined direction of rubbing in the effective screen is 700 μm or more, the spacers are arranged in the same direction as the rubbing direction. The distance between the arranged spacers can be sufficiently set, and the rubbing cloth's bristle tip and the spacer are buffered during rubbing, and the bristle tip is reduced. For this reason,
Since the substrate surface is evenly and sufficiently rubbed, the orientation is stable.

According to a seventh aspect of the present invention, in the method of manufacturing a liquid crystal display device according to the second aspect, the spacer is formed by a photolithography method. Thus, claim 2, 3, 4, 5
Alternatively, in the method of manufacturing a liquid crystal display device according to item 6, since the spacer is formed by a photolithography method, the spacer can be formed in the same process as in the related art.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIG. FIG. 1 is a plan view in an effective screen showing an example of a counter substrate according to an embodiment of the present invention.

In this method of manufacturing a liquid crystal display device, a black matrix layer made of a metal or a pigment resin and red, green, and blue color layers 4 are formed on a surface of an opposing substrate by photolithography. A single or a plurality of array chips are formed on the surface of the substrate, and rubbing the surfaces of the counter substrate and the array substrate in the directions a and b respectively so that the angles A and B (0 ° ≦ angle A ≦ 360 °,
0 ° ≦ angle B ≦ 360 °, angle A３angle B or angle A = angle B), and a sealing material as an adhesive is formed on either the surface of the counter substrate or the surface of the array substrate. In a configuration in which a liquid crystal layer is sandwiched between opposing gaps of the single panel and a liquid crystal display panel is formed, the black matrix layer on the opposing substrate is After the formation of the color layer 4,
When a resin having polyimide or acrylic is overlapped and laminated to form a spacer 5 for regulating rigid bodies in a substrate gap, a spacer 5 adjacent to an effective screen is formed.
The spacer 5 is formed so that the direction in which r and 5s are arranged and the direction at the angle A are not substantially parallel.

As shown in the figure, the rubbing direction at an angle A of the opposing substrate is 7, and the BM opening 3 and the red layer 4A, green layer 4B and blue layer 4C which are color filters are formed on the substrate. Are formed. Further, on the color layer 4, a spacer 5 in which a transparent resin layer or a black matrix layer and a part of the red, green and blue color layers 4 are overlapped and laminated is formed by photolithography. Is
In the direction substantially equal to the rubbing direction 7, the rubbing direction is designed and formed in the direction indicated by 6.

In the above arrangement design, the distance between the spacer arrangements (spacers 5r and 5t) arranged in the six directions is as follows.
It is formed with a sufficient distance (for example, FIG.
In the case of the 5-inch XGA, the distance between the spacer arrangements in the arrangement direction 6 is about 1331 μm. The spacer density at this time is about 8.50 pieces / mm 2. ). For this reason, at the time of rubbing, the bristle tips of the rubbing cloth and the spacers are buffered and the bristle tips are less likely to be pushed away, so that the substrate surface is evenly and sufficiently rubbed with rubbing. Therefore, light leakage due to non-alignment failure can be reduced, and the orientation (alignment regulating force) of the substrate surface can be stabilized for a long time.

Also, depending on the panel size and the number of pixels,
In some cases, the spacer arrangement is designed so that the spacer arrangement direction 6 and the rubbing direction 7 in FIG.

In this embodiment, the spacers are formed on a single layer of red, green, and blue color layers or on a plurality of color layers of three colors. Either case is fine.

Further, as described in the above (prior art), there is a restriction on the design rule that the spacer arrangement position is formed above the X-direction signal line, that is, arranged in units of dots and pixels. Therefore, the distance between the spacer arrangements formed in the rubbing direction is at least 700 μm or more, but the distance between the arrangements may be one dot or one pixel (pixel) or more. For example, 22 type wide VG
In A, the long side of one dot is about 600 microns,
This is because the distance of one pixel in the diagonal direction at 45 ° (diagonal distance) is about 800 μm, which is equivalent to the restriction of about 700 μm or more. That is, depending on the size and the number of pixels, one dot or one pixel is equivalent to a distance of about 700 μm or more.

The rubbing direction of the counter substrate may be any angle from 0 to 360 degrees depending on the main viewing angle direction of the target liquid crystal display panel and the liquid crystal mode (TN mode or IPS mode). With respect to the above angle, the distance between the spacers on the counter substrate may be designed and formed in advance as in the above-described embodiment.

In the method of forming a spacer on the opposing substrate, the spacer is formed such that the rubbing direction and the spacer forming direction are substantially the same in the same manner as described above, not only within the effective screen but also outside the effective screen. It is preferred that

The method for forming a counter substrate according to the present invention is not limited to the above embodiment.

[0031]

According to the liquid crystal display device of the first aspect of the present invention, in the structure in which the spacer for regulating the gap between the substrates is formed on the opposing substrate, the arrangement direction of the adjacent spacers in the effective screen and the rubbing are performed. Since the spacer is formed so that the predetermined direction does not become substantially parallel, the tip of the rubbing cloth and the spacer are buffered during rubbing, and the tip of the bristle is less likely to be displaced, and the tip of the rubbing is reduced on the substrate surface. Can be reached enough. Therefore, light leakage due to poor non-alignment can be reduced, and the alignment (alignment regulating force) of the substrate surface is stable for a long time. As a result, a liquid crystal display panel with high yield and high reliability can be manufactured.

According to the method of manufacturing a liquid crystal display device according to the second aspect of the present invention, when forming a spacer for regulating the gap between the substrates on the opposing substrate, rubbing is performed with the arrangement direction of the adjacent spacers in the effective screen. Since the spacer is formed so that the predetermined direction does not become substantially parallel, the opposing substrate designed and arranged to form the spacer in this manner, at the time of rubbing, the bristle tips of the rubbing cloth and the spacer are buffered, and the bristle tips are formed. Since it is less likely to be pushed away, the bristle tip can sufficiently reach the substrate surface. Therefore, since the substrate surface is evenly rubbed by rubbing, even when a liquid crystal display panel is manufactured using the counter substrate thereafter, light leakage due to non-alignment failure can be reduced, and the alignment of the substrate surface (alignment regulating force). Is stable for a long time. As a result, the yield and reliability can be improved, which is extremely effective practically.

According to the third aspect of the present invention, the spacer is formed by laminating the black matrix layer and a part of the red, green and blue color layers when the black matrix layer and the color layer on the counter substrate are formed. It can be easily manufactured without increasing the number of steps.

According to the fourth aspect of the present invention, the spacer is formed such that the distance between the spacers disposed in substantially the same direction as the predetermined direction of rubbing in the effective screen is equal to or more than the diagonal distance of one dot. The distance between the spacers arranged in substantially the same direction as that of the rubbing cloth can be sufficiently secured, and the rubbing cloth's bristle tip and the spacer are buffered and the bristle tip is reduced. As a result, the substrate surface is evenly and sufficiently rubbed, so that the orientation is stabilized.

According to the fifth aspect of the present invention, the spacer is formed such that the distance between the spacers disposed in substantially the same direction as the predetermined direction of rubbing in the effective screen is equal to or greater than the diagonal distance of one pixel. The distance between the spacers arranged in substantially the same direction as that of the rubbing cloth can be sufficiently secured, and the rubbing cloth's bristle tip and the spacer are buffered and the bristle tip is reduced. As a result, the substrate surface is evenly and sufficiently rubbed, so that the orientation is stabilized.

According to the sixth aspect, the spacer is formed so that the distance between the spacers disposed in the same direction as the predetermined direction of rubbing in the effective screen is 700 μm or more. The distance between the spacers arranged in the directions can be sufficiently set, and the rubbing cloth's bristle tip and the spacer are buffered during rubbing, and the bristle tips are reduced. As a result, the substrate surface is evenly and sufficiently rubbed, so that the orientation is stabilized.

According to a seventh aspect of the present invention, in the method of manufacturing a liquid crystal display device according to the second, third, fourth, fifth, or sixth aspect, the spacer is formed by a photolithography method. .

[Brief description of the drawings]

FIG. 1 is a plan view in an effective screen showing an example of a counter substrate in a method of manufacturing a liquid crystal display device according to an embodiment of the present invention.

FIG. 2 is a plan view in an effective screen showing an example of a counter substrate in a conventional method of manufacturing a liquid crystal display device

FIG. 3 is a plan view in an effective screen showing another example of a counter substrate in a conventional method of manufacturing a liquid crystal display device.

FIG. 4 is a cross-sectional view in an effective screen showing an example of a counter substrate in a conventional method of manufacturing a liquid crystal display device.

FIG. 5 is a cross-sectional view in an effective screen showing another example of a counter substrate in a conventional liquid crystal display device manufacturing method.

FIG. 6 is a plan view in an effective screen showing an example of a non-alignment defective portion of a counter substrate in a conventional method of manufacturing a liquid crystal display device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Glass substrate 2 Black matrix layer 3 Opening 4A Red color layer pattern part 4B Green color layer pattern part 4C Blue color layer pattern part 5 Example spacer 5A Conventional example spacer 5B Conventional example spacer 5C Conventional example Spacer made of a transparent resin layer 5D Spacer made of a stack of color layers in the conventional example 6 Spacer arrangement forming direction almost in the same direction as the rubbing direction 7 Rubbing direction 8 Light leakage part due to non-alignment defect generated in the conventional example

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Hiroshi Ouchida 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. F term (reference) 2H089 KA11 LA09 LA16 LA20 NA14 QA12 QA15 QA16 TA12 TA13 2H090 LA02 MA06 MB01 2H091 FA04Y FA35Y FD06 GA06 GA08 LA12 LA30

Claims (7)

[Claims] An array substrate having one or more array chips formed on a surface thereof, a counter substrate facing the array substrate, and a liquid crystal layer sandwiched between substrate gaps.
A liquid crystal display device in which alignment is controlled at a predetermined angle by rubbing the surfaces of the counter substrate and the array substrate in predetermined directions, and spacers for regulating the substrate gap are formed on the counter substrate. A liquid crystal display device, wherein the spacers are formed such that the arrangement direction of the adjacent spacers in the effective screen and the predetermined rubbing direction are not substantially parallel. 2. A step of laminating and forming a black matrix layer and red, green and blue color layers on a surface of a counter substrate, a step of forming one or a plurality of array chips on a surface of an array substrate, and Rubbing the surfaces of the substrate and the array substrate in predetermined directions, respectively, to control the orientation at predetermined angles, bonding the opposing substrate and the array substrate so as to face each other, and sandwiching a liquid crystal layer in a substrate gap. In forming the spacer for regulating the substrate gap on the counter substrate, the spacer is formed so that the direction in which the adjacent spacers are arranged in the effective screen and the predetermined direction for rubbing are not substantially parallel to each other. A method of manufacturing a liquid crystal display device. 3. The spacer according to claim 2, wherein the spacer is overlapped with the black matrix layer and a part of the red, green and blue color layers when the black matrix layer and the color layer are formed on the counter substrate. A method for manufacturing a liquid crystal display device. 4. The spacer according to claim 2, wherein a distance between the spacers disposed in substantially the same direction as a predetermined direction of rubbing in the effective screen is equal to or more than a diagonal distance of one dot. Of manufacturing a liquid crystal display device. 5. The spacer according to claim 2, wherein the spacer arranged in the same direction as the predetermined direction of rubbing in the effective screen has a distance between the spacers of not less than one pixel diagonal. Of manufacturing a liquid crystal display device. 6. A distance between arrangements of spacers arranged in substantially the same direction as a predetermined direction for rubbing in an effective screen is 700.
4. The method for manufacturing a liquid crystal display device according to claim 2, wherein the spacer is formed so as to have a thickness of at least one micrometer. 7. The method according to claim 2, wherein the spacer is formed by a photolithography method.