JP4059826B2 - Color filter substrate and liquid crystal panel using the same - Google Patents

Description

  The present invention relates to a color filter substrate and a liquid crystal panel using the same, and more particularly to a color filter substrate suitable for an electrostatic chuck that is not affected by static electricity and a liquid crystal panel using the same.

  In the manufacturing process of a liquid crystal panel, a vacuum method has generally been adopted as a method for enclosing a liquid crystal material in a gap between a color filter substrate and an array substrate. This vacuum method is as follows. First, the color filter substrate and the array substrate are bonded together. Since a plurality of liquid crystal panels are simultaneously formed on the bonded substrate, the individual liquid crystal panels are cut and separated from the bonded substrate. Next, the liquid crystal panel and the container containing the liquid crystal material are placed in an airtight device, and the inside of the airtight device is evacuated. When the gap between the liquid crystal panels reaches a vacuum, the liquid crystal panel inlet is immersed in a liquid crystal material, and the inside of the apparatus is returned to atmospheric pressure with nitrogen gas or the like. As a result, the liquid crystal material is filled in the gaps of the liquid crystal panel by the capillary phenomenon and the pressure difference.

  However, with the increase in size of liquid crystal panels, the above-mentioned vacuum system cannot smoothly fill liquid crystal material into the gaps of the liquid crystal panels, and sufficient alignment accuracy cannot be obtained. It has become difficult to produce. For this reason, a dripping method has been newly adopted as a liquid crystal material sealing method. In this dropping method, a liquid crystal material is dropped onto one substrate before the color filter substrate and the array substrate are bonded together, and then the two substrates are bonded together (for example, Patent Document 1).

  FIG. 7 shows a schematic diagram of an apparatus used for bonding substrates in the dropping method. In this apparatus, a mounting table 5 and a suction plate 41 equipped with an electrostatic chuck 42, which is mounted so as to be movable up and down, facing the mounting table 5, are disposed in the vacuum chamber 6. Then, the array substrate 2 onto which a liquid crystal material (not shown) is dropped is placed on the mounting table 5, and the color filter substrate 1 on which the seal member 3 is drawn is sucked by the electrostatic chuck 42 and supported by the suction plate 41. , Located on the array substrate 2. After the vacuum chamber 6 is evacuated, the suction plate 41 is moved downward and pressed to bond the color filter substrate 1 and the array substrate 2 together. Next, the sealing member 3 is cured by irradiating the sealing member 3 with ultraviolet rays to firmly bond the two substrates.

  Here, the electrostatic chuck 42 is used to attract and hold the color filter substrate 1 for the following reason. In the conventional vacuum method, since two substrates can be bonded under atmospheric pressure, a vacuum chuck is generally used to hold the color filter substrate by suction. However, in the dripping method, the color filter substrate must be sucked and held in a vacuum chamber, and a vacuum chuck cannot be used.

However, since the glass substrate normally used as the insulating substrate of the color filter substrate is a dielectric, the color filter substrate is charged when the color filter substrate is attracted and held by an electrostatic chuck. FIG. 8 is a partial sectional view of FIG. When positive and negative charges are alternately generated on the surface of the electrostatic chuck 42, polarization occurs in the glass substrate (insulating substrate) 11 facing the electrostatic charge 42, and the charge opposite in polarity to the surface charge of the electrostatic chuck 42 is electrostatic chuck. Move to the side. Thereby, the glass substrate 11 is attracted and held by the electrostatic chuck 42. On the other hand, the charge having the same polarity as the surface charge of the electrostatic chuck 42 moves to the opposite side of the glass substrate 11 from the electrostatic chuck 42. In the portion where the counter electrode film 14 is formed on the surface of the glass substrate, the charge due to electrostatic polarization is removed by the counter electrode film 14, but the peripheral portion of the glass substrate 11 where the counter electrode film 14 is not formed. Then, the electric charge remains as it is. For this reason, when the color filter substrate 1 approaches the array substrate 2, the charge on the surface of the color filter substrate 1 moves to the wiring 22 on the surface of the array substrate 2 and destroys the transistors 23 and the like formed on the array substrate 2. There was a problem. Therefore, in order to remove static electricity from the color filter substrate 1, it has been proposed to form a transparent conductive film or a conductive black matrix in a non-display area such as a peripheral portion of the color filter substrate 11 (for example, Patent Document 2). ).
Japanese Unexamined Patent Publication No. 2000-66163 (page 9, FIG. 3, FIG. 4) JP 2001-147314 A (Claims, page 3, right column, FIGS. 1 and 2)

  However, when a conductive black matrix is formed in the non-display area of the color filter substrate, there is a problem that the light-shielding area increases and a photocurable sealing member cannot be used. In addition, when a transparent conductive film is formed in the non-display area of the color filter substrate, the adhesion with the seal member is lowered and the seal member may be peeled off from the color filter substrate.

  The present invention has been made in view of such conventional problems, and an object of the present invention is to provide a color filter substrate and a liquid crystal panel that are less likely to be charged by static electricity and that have good adhesion to a seal member. There is to do.

  Another object of the present invention is to provide a color filter substrate and a liquid crystal panel in which corrosion caused by a potential difference between the substrates does not occur even in a high humidity environment.

  In order to achieve the above object, according to the present invention, an array substrate in which a plurality of thin film transistors are arranged on an insulating substrate is opposed to each other with a predetermined gap, and an outer periphery thereof is sealed with a sealing member, and a liquid crystal material is placed in the gap. Is a color filter substrate constituting a liquid crystal panel, and a counter electrode film is formed on the entire surface of one side of the insulating substrate so as to cover the color filter layer formed on the insulating substrate. A color filter substrate is provided in which an opening is provided in a portion in contact with the seal member and in a portion not facing a wiring formed on the array substrate.

  According to the invention, a color filter substrate having a color filter layer formed on an insulating substrate and a counter electrode film formed so as to cover the color filter layer, and a plurality of thin film transistors arranged on the insulating substrate, An array substrate disposed opposite to the filter substrate with a predetermined gap; a color filter substrate disposed opposite to the filter substrate; a seal member that seals an outer peripheral portion of the array substrate; and a liquid crystal material sealed in the gap. In the liquid crystal panel, the counter electrode film is formed on the entire surface of one side of the insulating substrate, and is a portion in contact with the seal member in the counter electrode film, and does not face the wiring formed on the array substrate. A liquid crystal panel characterized in that an opening is provided in the portion is provided.

  Here, from the viewpoint of protecting the counter electrode film, further improving the adhesion with the seal member, and preventing corrosion, on the portion of the counter electrode film that is in contact with the seal member and on the outer region from there An insulating resin film may be further formed.

  In addition, from the viewpoint of preventing corrosion due to moisture in a high-humidity environment, a conductive layer is provided on at least a part of the surface of the array substrate that is in contact with the seal member and an area outside the insulating layer via an insulating layer. It may be formed.

  In the color filter substrate and the liquid crystal panel of the present invention, since the counter electrode film of the color filter substrate is formed on the entire surface of one side of the insulating substrate, charging due to static electricity hardly occurs, and even if it is attracted and held by the electrostatic chuck, it is caused by static electricity. There is no problem. In addition, an opening is provided in a portion of the counter electrode film that contacts the seal member and does not face the wiring formed on the array substrate, and the insulating substrate surface exposed from the opening is directly bonded to the seal member. Since it did in this way, the adhesiveness of a sealing member improves markedly.

  If an insulating resin film is further formed on a portion of the counter electrode film that is in contact with the seal member and an area outside thereof, peeling of the counter electrode film from the insulating substrate can be prevented and corrosion due to moisture can be prevented.

  In addition, even if a conductive layer is formed on at least a part of the surface of the array substrate that is in contact with the sealing member and an outer region from the surface, the corrosion due to moisture in a high humidity environment, etc. Can be prevented.

  Hereinafter, the color filter substrate and the liquid crystal panel of the present invention will be described with reference to the drawings. The present invention is not limited to these embodiments.

  FIG. 1 is a schematic plan view of the color filter substrate and the array substrate. FIG. 2A is a schematic plan view of the array substrate 2. In the array substrate 2, a display unit 24 in which a plurality of thin film transistors (not shown) are arranged in a matrix is formed on the surface of a rectangular glass substrate (insulating substrate) 21, and a sealing member is provided so as to surround the display unit 24. 3 is the bank. A wiring 22 such as a gate wiring and a data wiring for operating each thin film transistor is extended to the edge of the glass substrate 21 across the seal member 3 so as to be connected to a driver (not shown).

  On the other hand, FIG. 2B is a schematic plan view of the color filter substrate 1. A color filter layer (not shown) is formed on a portion of the color filter substrate 1 facing the display portion 24 of the array substrate 2. The entire surface of one side of the glass substrate 11 including the color filter layer is covered with the counter electrode film 14. An opening 15 is formed in a portion of the counter electrode film 14 in contact with the seal member 3 of the array substrate 2.

  FIG. 2 shows a partial state diagram when the color filter substrate 1 and the array substrate 2 are bonded together. A counter electrode film 14 is formed on the entire lower surface of the color filter substrate. In addition, an opening 15 is formed in the counter electrode film 14 at a portion that is in contact with the seal member 3 indicated by a broken line and that is not opposed to the wiring 22 of the array substrate 1. In other words, the seal member 3 makes a large amount of contact with the glass substrate 11 of the color filter substrate 1 exposed by the opening 15 and always forms the counter electrode film 14 on the surface of the color filter substrate facing the wiring 22 of the array substrate 2. Has been. As a result, as shown in FIG. 3, when the color filter substrate 1 is attracted and held by the electrostatic chuck 42, the charges generated by electrostatic polarization and moving to the side surface of the array substrate of the glass substrate 11 14 is removed. In addition, since the counter electrode film 14 is always formed on the formation region of the thin film transistor 23 and the portion of the color filter substrate facing the wiring 22, even if the color filter substrate 1 is brought close to the array substrate 2, Problems such as destruction of the thin film transistor 23 on the substrate 2 can be reliably prevented.

  FIG. 4 is a cross-sectional view taken along line AA in FIG. Since the counter electrode film 14 of the color filter substrate 1 is removed except for a portion facing the wiring 22 of the array substrate 2 to form an opening 15, most of the seal member 3 is the glass substrate 11 of the color filter substrate 1. It is directly adhered to. Since the counter electrode film 14 is usually a metal particle film such as an ITO film, the adhesion with the glass substrate 11 is inferior to that of the seal member 3. Therefore, by directly bonding the glass substrate 11 and the seal member 3 as shown in FIG. 4, the adhesive force is much stronger than when the glass substrate 11 is contacted via the counter electrode film 14.

  The width of the opening 15 formed in the counter electrode film 14 is preferably substantially equal to the width of the seal member 3 when the color filter substrate 1 and the array substrate 2 are bonded together. In addition, since the sealing member 3 is crushed and becomes larger than the original width by bonding the two substrates, the opening 15 is made wider than the original width of the sealing member 3 in anticipation of this widening. It is good to leave.

  The method for forming the opening 15 in the counter electrode film 14 is not particularly limited, but for example, it may be manufactured as follows. After the color filter layer 12 is formed on the glass substrate 11, the counter electrode film 14 is deposited on the entire surface of one side of the glass substrate 11 by sputtering so as to cover the color filter layer 12. Next, a negative photosensitive resin is applied to the glass substrate 11 and prebaked, and then a portion corresponding to a portion where the opening 15 is formed is shielded from light with a photomask. Then, the color filter substrate 1 may be manufactured by performing development, post-baking, etching, peeling of the photosensitive resin, and drying. In the case where a positive photosensitive resin is used, a photomask having a hole in a portion corresponding to a portion where the opening 15 is formed is used.

  Regarding the adhesion between the counter electrode film and the glass substrate, since the liquid crystal material is enclosed in the region surrounded by the seal member, the adhesion is less likely to be a problem, but the counter electrode film is in contact with the seal member. There is a possibility that the above-mentioned adhesion may be a problem in the outer area from the portion where the area is present. Therefore, it is recommended to further form an insulating resin film in such a region. An example is shown in FIG. FIG. 5 is a partial cross-sectional view of the color filter substrate 1 on which the insulating resin film 16 is formed. The insulating resin film 16 is formed from a part of the formation region of the seal member 3 to the outer region. Thereby, peeling of the counter electrode film 14 from the glass substrate 11 is prevented, and at the same time, corrosion due to moisture described below is also prevented.

  Examples of the resin material for forming such an insulating resin film include acrylic resin, epoxy resin, polyimide resin, and silicon resin. The insulating resin film may be formed, for example, by forming a counter electrode film on a glass substrate and then applying and curing the predetermined electrode region. The thickness of the insulating resin film is preferably about several μm.

  Further, when the liquid crystal display device is used in a high humidity environment, moisture is adsorbed between the color filter substrate and the array substrate, and the metal part formed on the substrate may be corroded. This is a phenomenon that occurs when there is a potential difference between the substrates, and it is presumed that the impurities move in the adsorbed moisture due to the potential difference, and the metal portion formed on the substrate erodes the impurities. . Therefore, in the present invention, it is recommended to form a conductive layer via an insulating layer on at least a portion of the surface of the array substrate that is in contact with the seal member and an area outside thereof.

  FIG. 6 is a partial cross-sectional view showing an example of a liquid crystal panel on which a conductive layer is formed. In the array substrate 2 in this figure, an insulating layer 24 and a conductive layer 25 are laminated in this order on a portion in contact with the seal member 3, an outer region from the portion, and a slightly inner region. The outer peripheral ends of the insulating layer 24 and the conductive layer 25 are positioned outside the outer peripheral end of the color filter substrate 1. As a result, all the surfaces of the opposing substrates are covered with the conductive member, no potential difference occurs between the substrates, and no corrosion occurs even if moisture is adsorbed between the substrates.

  A black matrix and red, green and blue color resists were applied on a glass substrate, and a color filter layer was formed by patterning. Then, an ITO film as a counter electrode film was deposited on the entire surface of one side of the glass substrate by sputtering so as to cover the color filter layer. Next, after photosensitive resin (negative type) is applied to the glass substrate and prebaked, the portion that comes into contact with the seal member and that does not face the wiring formed on the array substrate is shielded with a photomask and exposed. It was. Thereafter, development, post-baking, etching, peeling of the photosensitive resin, and drying were performed to produce a color filter substrate shown in FIG. Then, a photo spacer material was formed on the black matrix to obtain a final color filter substrate. The produced color filter substrate was sucked and held by an electrostatic chuck, and the surface potential of the outer portion from the seal member on the lower surface of the color filter substrate was measured. Note that the wiring potential condition of the electrostatic chuck was ± 2 KV. Moreover, the liquid crystal panel destruction load when the terminal part of a liquid crystal panel was pushed was measured as peeling strength of a sealing member. The measurement results are shown in Table 1.

  After producing the color filter substrate shown in FIG. 1 in the same manner as in Example 1, an insulating resin film is applied to the entire surface of one side of the color filter substrate before forming the photo spacer, and a photosensitive resin (negative type) is further formed thereon. Was applied and prebaked. Then, the color filter layer region and part of the seal member region were shielded with a photomask and exposed. Thereafter, development, post-baking, etching, peeling of the photosensitive resin, and drying were performed to produce a color filter substrate shown in FIG. In the same manner as in Example 1, the produced color filter substrate was sucked and held by an electrostatic chuck, and the surface potential of the outer portion from the seal member on the lower surface of the color filter substrate was measured. The liquid crystal panel breaking load was also measured. The measurement results are shown in Table 1.

Comparative Example 1

  A black matrix and red, green and blue color resists were applied on a glass substrate, and a color filter layer was formed by patterning. Then, an ITO film as a counter electrode film was deposited on the entire surface of one side of the glass substrate by sputtering so as to cover the color filter layer. Next, a photosensitive resin (negative type) was applied to a glass substrate and prebaked, and then light exposure was performed by shielding light except for the color filter layer portion with a photomask. Thereafter, development, post-baking, etching, peeling of the photosensitive resin, and drying were performed to produce a color filter substrate shown in FIG. Then, a photo spacer material was formed on the black matrix to obtain a final color filter substrate. In the same manner as in Example 1, the produced color filter substrate was sucked and held by an electrostatic chuck, and the surface potential of the outer portion from the seal member on the lower surface of the color filter substrate was measured. The liquid crystal panel breaking load was also measured. The measurement results are shown in Table 1.

表１から明らかなように、シール部材のカラーフィルタ基板への接着強度は実施例１及び実施例２のカラーフィルタ基板では、２．０〜５．０（６．０）ｋｇ／ｃｍ２と従来と同程度であった。また、これらのカラーフィルタ基板の表面電位は６０〜８０ｅＶと非常に低い値であった。これに対し比較例１のカラーフィルタ基板では、表面電位が−２００〜９００ｅＶと高い値であった。

As is clear from Table 1, the adhesive strength of the seal member to the color filter substrate is 2.0 to 5.0 (6.0) kg / cm 2 in the color filter substrates of Example 1 and Example 2, and It was about the same. Further, the surface potential of these color filter substrates was a very low value of 60 to 80 eV. In contrast, in the color filter substrate of Comparative Example 1, the surface potential was as high as -200 to 900 eV.

It is each top view of the color filter substrate and array substrate of this invention. It is a state figure when a color filter substrate and an array substrate are bonded together. FIG. 3 is a state diagram when the color filter substrate and the array substrate of the present invention are bonded together. It is the sectional view on the AA line of FIG. It is a fragmentary sectional view showing other embodiments of a color filter substrate of the present invention. It is a fragmentary sectional view which shows other embodiment of the liquid crystal panel of this invention. It is sectional drawing of an apparatus which performs dripping type liquid crystal material enclosure. It is sectional drawing which shows the conventional board | substrate bonding.

Explanation of symbols

1 Color filter substrate 2 Array substrate 3 Sealing member 11 Glass substrate (insulating substrate)
12 Color filter layer 13 Black matrix layer 14 Counter electrode film 15 Opening 16 Insulating resin layer 21 Glass substrate (insulating substrate)
22 wiring 23 thin film transistor 24 insulating layer 25 conductive layer 42 electrostatic chuck

Claims (5)

A color filter substrate in which a plurality of thin film transistors are arranged on an insulating substrate so as to be opposed to each other with a predetermined gap, and an outer periphery thereof is sealed with a sealing member, and a liquid crystal material is sealed in the gap to constitute a liquid crystal panel Because
A counter electrode film is formed on the entire surface of one side of the insulating substrate so as to cover the color filter layer formed on the insulating substrate, and the counter electrode film is formed on the array substrate at a portion in contact with the seal member. A color filter substrate, wherein an opening is provided in a portion not facing the formed wiring.   The color filter substrate according to claim 1, further comprising an insulating resin film formed on a portion of the counter electrode film that is in contact with the seal member and on a region outside thereof. A color filter substrate having a color filter layer formed on an insulating substrate and a counter electrode film formed to cover the color filter layer, and a plurality of thin film transistors are arranged on the insulating substrate, with a predetermined gap from the color filter substrate. A liquid crystal panel comprising: an array substrate disposed opposite; a color filter substrate disposed opposite; a seal member that seals an outer periphery of the array substrate; and a liquid crystal material sealed in the gap,
The counter electrode film is formed on the entire surface of one side of the insulating substrate, and an opening is provided in a portion of the counter electrode film that is in contact with the seal member and not in opposition to the wiring formed on the array substrate. A liquid crystal panel characterized by that.   The liquid crystal panel according to claim 3, wherein an insulating resin film is further formed on a portion of the counter electrode film that is in contact with the seal member and a region outside the portion.   5. The liquid crystal panel according to claim 3, wherein a conductive layer is formed on at least a part of a portion of the surface of the array substrate that is in contact with the seal member and an area outside the portion through an insulating layer.

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