JP2010175727A - Liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display device that can narrow the frame and has high display quality. <P>SOLUTION: This liquid crystal display device includes an active area 120 constituted by a plurality of pixels. The liquid crystal display device includes an array substrate 200 having a pixel electrode 230 for each pixel, a counter substrate 300 arranged so as to face the pixel electrodes of the array substrate, a seal material 110 that is arranged around the active area while securing an inlet 111 for injecting liquid crystal material between the array substrate and counter substrate, and sticks the array substrate to the counter substrate, a liquid crystal layer 400 made of liquid crystal material held between the array substrate and counter substrate, a continuously formed first sidewall 510 that is arranged between the active area and seal material while securing the inlet, and a second sidewall 520 arranged so as to grip the seal material between it and the first sidewall. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a liquid crystal display device, and more particularly to a liquid crystal display device having a structure that suppresses the spread of a sealing material for bonding a pair of substrates.

  A typical liquid crystal display device as a flat display device includes a liquid crystal display panel configured by holding a liquid crystal layer between an array substrate and a counter substrate bonded together with a sealant. This liquid crystal display panel includes an active area composed of matrix pixels.

  A sealing material for bonding the pair of substrates is disposed so as to surround the active area. Such a sealing material is applied to one substrate and then cured while being pressed in a state where the other substrate is overlapped. At this time, the sealing material spreads in the width direction. A part of the spread sealing material may flow into the active area. The seal material that has flowed into the active area causes display defects. For this reason, it is required to prevent the sealing material from flowing into the active area.

In response to such a problem, for example, according to Patent Document 1, a technique of disposing a protrusion pattern between an active area and a seal portion where a seal material is disposed is disclosed.
JP 2008-15370 A

  In recent years, there has been a demand for a narrow frame panel that has a short distance from the active area to the panel edge. On the other hand, it is necessary to secure the width outside the active area in consideration of the positional accuracy and the width accuracy when applying the sealing material arranged outside the active area, and further narrowing of the frame is required.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a liquid crystal display device capable of narrowing the frame and having good display quality.

According to one aspect of the invention,
A liquid crystal display device having an active area composed of a plurality of pixels,
A first substrate having a pixel electrode in each of the pixels;
A second substrate disposed to face the pixel electrode of the first substrate;
A sealing material that is disposed around the active area while securing an injection port for injecting a liquid crystal material between the first substrate and the second substrate, and bonds the first substrate and the second substrate together. When,
A liquid crystal layer made of a liquid crystal material held between the first substrate and the second substrate;
A first side wall disposed continuously between the active area and the sealing material while securing the injection port;
A second side wall disposed so as to sandwich the sealing material with the first side wall;
A liquid crystal display device is provided.

According to one aspect of the present invention,
A liquid crystal display device having an active area composed of a plurality of pixels,
A first substrate having a pixel electrode in each of the pixels;
A second substrate disposed to face the pixel electrode of the first substrate;
A sealing material that is arranged in a loop so as to surround the active area, and bonds the first substrate and the second substrate;
A liquid crystal layer made of a liquid crystal material held between the first substrate and the second substrate;
A first sidewall disposed between the active area and the sealing material and formed in a loop shape;
A second side wall disposed so as to sandwich the sealing material with the first side wall;
A liquid crystal display device is provided.

  According to the present invention, it is possible to provide a liquid crystal display device capable of narrowing the frame and having good display quality.

  A liquid crystal display device according to an embodiment of the present invention will be described below with reference to the drawings.

  As shown in FIG. 1, the liquid crystal display device includes a liquid crystal display panel 100 having a substantially rectangular flat plate shape. The liquid crystal display panel 100 includes a pair of substrates, that is, an array substrate (first substrate) 200 and a counter substrate (second substrate) 300, and a liquid crystal layer made of a liquid crystal material held between the array substrate 200 and the counter substrate 300. 400. The array substrate 200 and the counter substrate 300 are bonded together with a sealant 110.

  The liquid crystal display panel 100 includes a substantially rectangular active area 120 that displays an image on the inner side surrounded by the sealing material 110. The active area 120 includes a plurality of pixels PX arranged in a matrix.

  The array substrate 200 includes a plurality of scanning lines Y (1, 2, 3,..., M) arranged in the active area 120 so as to extend along the row direction H of the pixels PX, and the column direction of the pixels PX. A plurality of signal lines X (1, 2, 3,..., N) arranged to extend along V, and switching arranged at intersections of the signal lines X and the scanning lines Y in each pixel PX. An element 220 and a pixel electrode 230 connected to the switching element 220 of each pixel PX are provided (where m and n are positive integers).

  For example, the switching element 220 includes a thin film transistor (TFT) including a semiconductor layer formed of amorphous silicon, polysilicon, or the like. Here, the semiconductor layer is formed of polysilicon.

  The gate electrode 222 of the switching element 220 is electrically connected to the scanning line Y (or formed integrally with the scanning line Y). The source electrode 225 of the switching element 220 is electrically connected to the signal line X (or formed integrally with the signal line X). The drain electrode 227 of the switching element 220 is electrically connected to the pixel electrode 230.

  The counter substrate 300 is arranged to face the pixel electrode 230 in the active area 120.

  In addition, the liquid crystal display panel 100 includes a signal supply unit 131 disposed on the outer peripheral portion 130 located outside the active area 120. The signal supply unit 131 has terminals that can be connected to a driving IC chip, a flexible wiring board, or the like that functions as a signal supply source including a gate driver and a source driver. Alternatively, the signal supply unit 131 may be configured as a driver including a thin film transistor (TFT) including a polysilicon semiconductor layer, and may be directly formed on the array substrate 200.

  In the example illustrated in FIG. 1, the signal supply unit 131 is disposed in the extending portion 200 </ b> E of the array substrate 200 that extends outward from the end portion 300 </ b> A of the counter substrate 300. For example, the array substrate 200 is formed in a quadrangular shape like the counter substrate 300, and is substantially aligned with the end portion of the counter substrate 300 on three sides (that is, the end portion of the array substrate 200 and the end portion of the counter substrate face each other). Only one side extends outward from the counter substrate 300.

  That is, the end portion 300 </ b> A of the counter substrate 300 does not face the end portion 200 </ b> A of the array substrate 200, and faces the wiring extending toward the signal supply unit 131 in the array substrate 200. As described above, in the example illustrated in FIG. 1, the extending portion 200 </ b> E is formed only along one side of the liquid crystal display panel 100.

  In particular, in this embodiment, the extending part 200E is located on an extension line in the column direction V of the liquid crystal display panel 100. That is, the signal supply unit 131 has one side of the outer peripheral portion 130 located on the extended line in the column direction V (that is, one side of the liquid crystal display panel 100 parallel to the end portion 200A of the array substrate 200 and the end portion 300A of the counter substrate 300). Are arranged along.

  As shown in FIG. 1, when the liquid crystal display panel 100 is viewed in a plan view, the extended portion 200 </ b> E corresponds to a region between the end portion 200 </ b> A of the array substrate 200 and the end portion 300 </ b> A of the counter substrate 300. The part 131 is disposed between the end part 200 </ b> A of the array substrate 200 and the end part 300 </ b> A of the counter substrate 300.

  Each of the scanning lines Y (1, 2, 3,..., M) arranged in the active area 120 is connected to the signal supply unit 131 via the outer peripheral portion 130. Similarly, each of the signal lines X (1, 2, 3,..., N) is connected to the signal supply unit 131 via the outer peripheral portion 130. A predetermined signal (that is, a scanning signal or a video signal) is supplied to the scanning line Y and the signal line X from a signal supply source via the signal supply unit 131.

  Next, the structures of the array substrate 200 and the counter substrate 300 will be described in more detail.

  As shown in FIG. 2, the array substrate 200 is formed by using a rectangular insulating substrate 210 having a light transmission property such as a glass substrate. The switching element 220 is disposed on one main surface of the insulating substrate 210 and is covered with an insulating film 240 formed using an inorganic material or an organic material.

  The pixel electrode 230 is disposed on the insulating film 240 and connected to the switching element 220 via a contact hole that penetrates the insulating film 240. In the transmissive liquid crystal display panel 100 that selectively transmits backlight light and displays an image, the pixel electrode 230 is made of, for example, indium tin oxide (ITO) or indium zinc oxide (IZO). It is formed of a conductive material having optical transparency. In the reflective liquid crystal display panel 100 that selectively reflects external light and displays an image, the pixel electrode 230 is a conductive material having light reflectivity such as aluminum (Al) or molybdenum (Mo). Is formed by.

  The array substrate 200 includes columnar spacers SP on the surface facing the counter substrate 300. The columnar spacers SP are integrally formed on the array substrate 200 using a resin material such as a photosensitive resin. Here, the columnar spacer SP is disposed on the insulating film 240. Note that the columnar spacer SP may be formed integrally with the counter substrate 300.

  The counter substrate 300 is formed using a rectangular insulating substrate 310 having optical transparency such as a glass substrate.

  In the color display type liquid crystal display device, the liquid crystal display panel 100 includes a plurality of types of pixels in the active area 120, for example, a red pixel that displays red (R), a green pixel that displays green (G), and a blue (B). Has a blue pixel.

  In the embodiment shown in FIG. 2, the counter substrate 300 includes a color filter layer 320 disposed on one main surface of the insulating substrate 310 in correspondence with each pixel PX in the active area 120. The color filter layer 320 is formed of a plurality of resin materials colored in red (R), green (G), and blue (B).

  That is, the counter substrate 300 includes, on the insulating substrate 310, a red color filter layer made of a resin colored so as to transmit light having a red main wavelength corresponding to the red pixel, and green corresponding to the green pixel. A green color filter layer made of a resin colored so as to transmit light of the principal wavelength of blue, and a blue color made of resin colored so as to transmit light of the blue dominant wavelength corresponding to the blue pixel A filter layer is provided.

  Such a color filter layer 320 may be provided on the array substrate 200.

  Further, the counter substrate 300 includes a frame-shaped light shielding layer 325 arranged so as to surround the active area 120 in the outer peripheral portion 130. The light shielding layer 325 is formed of, for example, a resin material colored in black.

  In the embodiment shown in FIG. 2, the counter substrate 300 includes a counter electrode 330 facing each of the pixel electrodes 230. The counter electrode 330 is disposed on the color filter layer 320 so as to face the plurality of pixels PX in the active area 120. The counter electrode 330 is formed of a light-transmitting conductive material such as ITO or IZO.

  The example shown in FIG. 2 corresponds to a vertical electric field mode that mainly uses a vertical electric field (an electric field substantially perpendicular to the main surface of the substrate), and the counter electrode 330 is opposed to the plurality of pixel electrodes 230 via the liquid crystal layer 400. As described above, the counter substrate 300 is provided, but the counter electrode 330 may be provided on the array substrate 200. That is, in the horizontal electric field mode mainly using the horizontal electric field (electric field substantially parallel to the main surface of the substrate), the counter electrode 330 is electrically insulated from the pixel electrode 230 and is opposed to the pixel electrode 230. 200.

  The surfaces of the array substrate 200 and the counter substrate 300 are respectively covered with alignment films (not shown) for controlling the alignment of liquid crystal molecules contained in the liquid crystal layer 400. An optical element (not shown) is disposed on the outer surface of the liquid crystal display panel 100. This optical element has a polarizing plate whose polarization direction is set in accordance with the characteristics of the liquid crystal layer 400, and is provided with a retardation plate as necessary.

  By the way, as shown in FIG. 1, the sealing material 110 is disposed between the array substrate 200 and the counter substrate 300 in a state where an injection port 111 for injecting a liquid crystal material is secured.

  That is, the sealing material 110 is formed of a resin material such as a thermosetting resin. This sealing material 110 uses a dispenser or the like so as to surround the active area 120 and form the injection port 111 on one surface of the liquid crystal display panel 100, for example, the surface of the array substrate 200 including the pixel electrodes 230. Applied. In the example shown in FIG. 1, the injection port 111 is formed on the side facing the signal supply unit 131 with the active area 120 interposed therebetween.

  Thereafter, in a state where the other substrate, for example, the surface of the counter substrate 300 provided with the counter electrode 330 or the like is disposed opposite to the array substrate 200, heating is performed while pressing the pair of substrates in a bonding direction. Thereby, the sealing material 110 is cured, and the array substrate 200 and the counter substrate 300 are bonded together. At this time, a predetermined cell gap for holding the liquid crystal layer 400 by the columnar spacer SP is formed between the array substrate 200 and the counter substrate 300.

  Thereafter, a liquid crystal material is injected from the injection port 111. Thereafter, as the sealing material 112, for example, a resin material such as an ultraviolet curable resin is applied to the injection port 111 and irradiated with ultraviolet rays, whereby the liquid crystal material is sealed in the cell gap. Thereby, the liquid crystal layer 400 held between the array substrate 200 and the counter substrate 300 is formed.

  In such an embodiment, the sealing material 110 is sandwiched between the pair of side walls in the outer peripheral portion 130. As shown in FIG. 1, in the liquid crystal display panel 100, the first side wall 510 is disposed between the active area 120 and the sealing material 110 while ensuring the injection port 111. The first side wall 510 is continuously formed in a square shape so as to surround the active area 120 except for the inlet 111. That is, the first side wall 510 is formed in a series, and both ends thereof are opposed to each other with an interval corresponding to the width of the inlet 111. Thereby, it is possible to ensure a predetermined liquid crystal injection efficiency without hindering the injection of the liquid crystal material from the injection port 111.

  The second side wall 520 is disposed so as to sandwich the sealing material 110 with the first side wall 510. That is, the second side wall 520 is disposed closer to the substrate end than the first side wall 510. The second side wall 520 is disposed substantially in parallel with the first side wall 510 so as to form a substantially constant interval with the first side wall 510. In the example illustrated in FIG. 1, the second side wall 520 is disposed along two opposing sides parallel to the long side of the active area 120 formed in a rectangular shape.

  According to such a configuration, the dispenser can be guided by the pair of side walls when the sealing material 110 is applied, and the application position accuracy can be improved. In addition, the sealant 110 can be applied between the pair of side walls, and the spread of the sealant 110 when the pair of substrates is bonded can be suppressed. Therefore, the width of the outer peripheral portion 130 can be reduced.

  Specifically, the width from the active area 120 to both sides 100B and 100C of the liquid crystal display panel 100 located on the extension line in the row direction H can be reduced. Therefore, the frame of the liquid crystal display device can be reduced.

  Note that the second side wall 520 may be arranged along four sides, like the first side wall 510. In this case, the width from the active area 120 to the four sides of the liquid crystal display panel may be reduced. it can.

  Moreover, since the 1st side wall 510 arrange | positioned inside the sealing material 110 is formed continuously, the inflow to the active area 120 of the sealing material 110 can be suppressed, and a display quality is maintained favorable. be able to. Further, even when the sealing material 110 is arranged close to the active area 120, since the flow of the sealing material 110 into the active area 120 can be suppressed, a large margin is not required, and further Narrow frame is possible.

  The second side wall 520 disposed outside the sealing material 110 is desirably formed intermittently. For example, as shown in FIG. 3, the second straight side wall 520 on the same straight line is constituted by a plurality of segments, and a gap is formed between the segments.

  Accordingly, it is possible to secure an escape path for excess sealing material among the sealing material 110 applied between the pair of side walls. For this reason, the applied sealing material 110 does not accumulate locally, the height of the sealing material 110 can be made uniform, and gap defects around the sealing material can be prevented.

  The first side wall 510 and the second side wall 520 are preferably sandwiched between the array substrate 200 and the counter substrate 300. That is, as shown in FIG. 2, the first sidewall 510 and the second sidewall 520 are in contact with both the insulating film 240 in the array substrate 200 and the light shielding layer 325 in the counter substrate 300.

  For this reason, it becomes possible to reliably prevent the sealant 110 from spreading toward the active area 120 side. In addition, contact between the liquid crystal material and the sealing material 110 can be avoided, and contamination of the liquid crystal material from the sealing material 110 (contamination of the liquid crystal material) can be suppressed.

  It is desirable that both the first side wall 510 and the second side wall 520 are integrally formed on the same substrate (that is, the array substrate 200 or the counter substrate 300). Even when the first side wall 510 and the second side wall 520 are formed on different substrates, the effect of suppressing the spread of the sealing material 110 during pressurization after bonding can be expected, but depending on the accuracy of bonding, the first side wall 510 and the second side wall 520 can be expected. It may be difficult to ensure a uniform spacing (line width of the sealing material) between the side wall 510 and the second side wall 520. For this reason, when the 1st side wall 510 and the 2nd side wall 520 are formed in the same board | substrate, the improvement of the line | wire width precision of the sealing material 110 can be anticipated.

  As described above, when the first sidewall 510 and the second sidewall 520 are formed on the same substrate, the first sidewall 510 and the second sidewall 520 can be collectively formed in the same process using the same material. . Such a side wall can be formed by a photolithography process using a photosensitive resin material.

  In this case, the first side wall 510 and the second side wall 520 are preferably formed of the same material on the same substrate as the columnar spacer SP. In the example shown in FIG. 2, the columnar spacer SP is formed integrally with the array substrate 200. In this case, the first sidewall 510 and the second sidewall 520 can be collectively formed in the same process using the same material as the columnar spacer SP. When formed in this way, the first side wall 510 and the second side wall 520 are disposed in the same layer (on the insulating film 240) as the columnar spacer SP.

  This eliminates the need for separate steps for forming the first side wall 510 and the second side wall 520, thereby preventing an increase in the number of manufacturing steps and costs.

  In the above-described example, the liquid crystal display panel 100 configured to inject the liquid crystal material through the injection port 111 has been described. However, the configuration in which the sealing material 110 is sandwiched between the pair of side walls in the present embodiment is a configuration in which the liquid crystal material is dropped. The present invention can also be applied to the liquid crystal display panel 100.

  That is, in the liquid crystal display panel 100 shown in FIG. 4, the array substrate 200 and the counter substrate 300 are bonded together by the sealing material 110 arranged in a loop so as to surround the active area 120. In FIG. 4, only the main parts necessary for the description are shown.

  The first side wall 510 disposed inside the sealing material 110 is formed in a loop shape, like the sealing material 110. The second side wall 520 outside the sealing material 110 is disposed so as to sandwich the sealing material 110 with the first side wall 510. In the example shown in FIG. 4, the second side wall 520 is disposed along two opposing sides parallel to the long side of the active area 120 formed in a rectangular shape, and is intermittently formed on the same straight line. .

  The liquid crystal display panel 100 having the above-described configuration is manufactured as follows.

  That is, on the surface of the array substrate 200 provided with the pixel electrodes 230 and the like, the columnar spacers SP are formed by, for example, a photolithography process using a photosensitive resin material, and at the same time, the loop-shaped first side wall 510 surrounding the active area 120. And a second side wall 520 spaced from the first side wall 510 on the substrate end side from the first side wall 510.

  Subsequently, the sealing material 110 is applied between the first side wall 510 and the second side wall 520 using a dispenser or the like. At this time, the sealing material 110 is formed in a loop shape so as to surround the active area 120.

  Then, before the sealing material 110 is cured, a liquid crystal material is dropped on the inner side surrounded by the first side wall 510 of the array substrate 200. Thereafter, in a state where the surface of the counter substrate 300 including the counter electrode 330 and the like is disposed so as to face the array substrate 200, heating is performed while pressing the pair of substrates in a bonding direction.

  Thereby, the sealing material 110 is cured, and the array substrate 200 and the counter substrate 300 are bonded together in a state where a predetermined cell gap is formed. Thereby, the liquid crystal display panel 100 in which the liquid crystal layer 400 is held in the cell gap between the array substrate 200 and the counter substrate 300 is formed.

  According to such a configuration, the dispenser can be guided by the pair of side walls when the sealing material 110 is applied, and the application position accuracy can be improved. In addition, the sealant 110 can be applied between the pair of side walls, and the spread of the sealant 110 when the pair of substrates is bonded can be suppressed. Therefore, the width of the outer peripheral portion 130 can be reduced.

  Moreover, since the 1st side wall 510 arrange | positioned inside the sealing material 110 is formed continuously, the inflow to the active area 120 of the sealing material 110 can be suppressed, and a display quality is maintained favorable. be able to. Further, the first side wall 510 is interposed between the uncured sealing material 110 and the dropped liquid crystal material, and can prevent the two from coming into direct contact with each other, so that contamination of the liquid crystal material can be suppressed.

  Also in such a liquid crystal display panel 100, the second side wall 520 disposed outside the sealing material 110 may be formed continuously as in the example shown in FIG. 1, or may be formed intermittently. However, it is desirable to form intermittently in order to secure an escape path for excess sealing material.

  In the example shown in FIG. 4, the second side wall 520 is arranged along two opposing sides parallel to the long side of the rectangular active area 120, but is arranged along the four sides. May be.

  In addition, the first side wall 510 and the second side wall 520 are preferably sandwiched between the array substrate 200 and the counter substrate 300.

  In addition, the first side wall 510 and the second side wall 520 are preferably formed integrally with the substrate to which the sealing material 110 is applied.

  As described above, according to this embodiment, it is possible to provide a liquid crystal display device that can be narrowed and has a good display quality.

  Note that the present invention is not limited to the embodiments as they are, and can be embodied by modifying the components without departing from the scope of the invention in the stage of implementation. Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiments. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine the component covering different embodiment suitably.

FIG. 1 schematically shows a configuration of a liquid crystal display panel of a liquid crystal display device according to an embodiment of the present invention. FIG. 2 is a cross-sectional view schematically showing the configuration of the liquid crystal display panel shown in FIG. FIG. 3 is a plan view schematically showing another structure of the second side wall that sandwiches the sealing material with the first side wall in the liquid crystal display panel shown in FIG. FIG. 4 is a diagram schematically showing a configuration of a liquid crystal display panel of a liquid crystal display device according to another embodiment of the present invention.

PX ... pixel Y ... scanning line X ... signal line 100 ... liquid crystal display panel 110 ... sealing material 111 ... injection port 120 ... active area 130 ... outer peripheral part 200 ... array substrate 220 ... switching element 230 ... pixel electrode 300 ... counter substrate 320 ... Color filter layer 325 ... Light-shielding layer 330 ... Counter electrode 400 ... Liquid crystal layer 510 ... First side wall 520 ... Second side wall

Claims (5)

A liquid crystal display device having an active area composed of a plurality of pixels,
A first substrate having a pixel electrode in each of the pixels;
A second substrate disposed to face the pixel electrode of the first substrate;
A sealing material that is disposed around the active area while securing an injection port for injecting a liquid crystal material between the first substrate and the second substrate, and bonds the first substrate and the second substrate together. When,
A liquid crystal layer made of a liquid crystal material held between the first substrate and the second substrate;
A first side wall disposed continuously between the active area and the sealing material while securing the injection port;
A second side wall disposed so as to sandwich the sealing material with the first side wall;
A liquid crystal display device comprising: A liquid crystal display device having an active area composed of a plurality of pixels,
A first substrate having a pixel electrode in each of the pixels;
A second substrate disposed to face the pixel electrode of the first substrate;
A sealing material that is arranged in a loop so as to surround the active area, and bonds the first substrate and the second substrate;
A liquid crystal layer made of a liquid crystal material held between the first substrate and the second substrate;
A first sidewall disposed between the active area and the sealing material and formed in a loop shape;
A second side wall disposed so as to sandwich the sealing material with the first side wall;
A liquid crystal display device comprising:   The liquid crystal display device according to claim 1, wherein the second side wall is formed intermittently.   The liquid crystal display device according to claim 1, wherein the first side wall and the second side wall are sandwiched between the first substrate and the second substrate.   The liquid crystal display device according to claim 1, wherein the first side wall and the second side wall are integrally formed on the first substrate or the second substrate.

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