JP2005215313A - Substrate for liquid crystal display panel and liquid crystal display panel using the same - Google Patents

Abstract

A liquid crystal display panel substrate capable of accurately aligning by providing an alignment mark for alignment and reliably preventing light leakage from a region near the alignment mark, and using the substrate Thus, there is provided a liquid crystal display panel that can be easily stored while being accurately aligned with the case and in which deterioration of display quality due to light leakage is remarkably suppressed.
A display region Dv surrounded by a black mask layer 15 on the opposite surface of the glass substrate 11 provided with a black mask layer 15 of a liquid crystal display panel Lp in which a pair of glass substrates 11 and 12 are opposed to each other. A first alignment mark 15a having a negative pattern is formed on a black mask pattern composed of an area to which the material of the black mask layer 15 is not applied at one corner around the first substrate, and the first alignment mark of the other glass substrate 12 is A light shielding film 22 is disposed in an area facing 15a.
[Selection] Figure 2

Description

The present invention relates to a liquid crystal display panel substrate and a liquid crystal display panel using the same.

  Usually, the liquid crystal display panel is used as a liquid crystal display module housed in a shield case. In this case, the effective display area of the liquid crystal display panel needs to be properly aligned and stored in the display window of the shield case. However, since the effective display area of the liquid crystal display panel is difficult to visually recognize, alignment marks for alignment are formed on the liquid crystal display panel, and alignment with respect to the shield case of the liquid crystal display panel is performed based on this.

  Conventional alignment masks for liquid crystal display panels form a black mask using the same material as the black mask provided to block the transmission of light from regions other than the pixel region, as disclosed in Patent Document 1. Often formed simultaneously. By doing so, it is not necessary to provide a new manufacturing process for forming the alignment mark, and an increase in manufacturing man-hours is avoided.

  However, when the alignment mark is formed of the same material as the black mask, the black mask 3 has an area for forming the alignment mark 2 at the corner of the substrate 1 and its area so that the alignment mark can be clearly recognized as shown in FIG. It is necessary to avoid the vicinity. For this reason, a light transmission area in which no black mask is provided around the alignment mark 2 is generated, and light leaks from this area, resulting in a decrease in display quality.

Further, a liquid crystal display panel is formed by joining the above-described substrate 1 and another substrate with a sealing material 4 and enclosing a liquid crystal inside the sealing material 4. The sealing material 4 is usually used for display. The black mask 3 is provided in the non-display area Dn provided with no obstruction. However, since the width of the black mask 2 is small at the corner portion where the alignment mark 2 is provided, the sealing material 4 may protrude from the non-display area Dn to the display area Dv. When the seal material 4 protrudes into the display area Dv, a display defect occurs in the protruded area and in the vicinity thereof.
JP 2003-156735 A

  An object of the present invention is to provide a liquid crystal display panel substrate capable of accurately and easily aligning by providing an alignment mark for alignment and reliably preventing light leakage from a region near the alignment mark, It is an object of the present invention to provide a high-quality liquid crystal display panel which can be easily stored by being accurately aligned with a case by using this substrate and in which deterioration of display quality due to light leakage is remarkably suppressed.

  In order to solve the above problems, the substrate for a liquid crystal display panel of the present invention is any one of a pair of substrates sandwiching a liquid crystal layer of the liquid crystal display panel, and at least displays one main surface. A black mask is formed by applying a light-shielding material on substantially the entire surface excluding the pixel area in the area and the predetermined area around the display area, and at least one of the predetermined areas serves as a reference alignment mark indicating the position of the substrate It is characterized by that.

  The liquid crystal display panel of the present invention is a liquid crystal display panel in which a liquid crystal layer is sandwiched between a pair of substrates at least one of which is transparent and has a rectangular planar shape, and the transparent first substrate includes: A light shielding material is applied to substantially the entire surface except at least a pixel area in a display area in which a plurality of pixels are arranged on one main surface and a predetermined area located at one substrate corner around the display area. Then, a black mask is formed, and the predetermined area is used as a first alignment mark serving as a reference indicating the position of the substrate, and the second substrate disposed opposite to the first substrate has its opposite main surface The second alignment mark is formed at one substrate corner portion located diagonally with respect to the first alignment mark.

  According to the substrate for a liquid crystal display panel of the present invention, since the alignment mark is a mark formed by not depositing a black mask material, that is, a negative type mark, light does not leak from the peripheral area of the alignment mark, By using this substrate, it is possible to easily obtain a high-quality liquid crystal display panel in which the deterioration of display quality due to light leakage is remarkably suppressed without increasing the number of manufacturing steps.

  In addition, according to the liquid crystal display panel of the present invention, since at least one alignment mark in the liquid crystal display panel obtained by bonding a pair of rectangular substrates is a negative type mark that does not deposit a black mask material, Light leakage from the alignment mark in the non-display area and the vicinity thereof (hereinafter referred to as the alignment mark arrangement area) can be remarkably suppressed, thereby expanding the range in which the alignment mark can be installed, and a pair of alignment marks can be connected to each other. As a result, the distance between the alignment marks can be ensured to be as long as possible, and the alignment of the liquid crystal display panel with respect to the case can be performed very accurately.

  In the liquid crystal display panel of the present invention, one edge of one substrate extends outside the corresponding end surface of the other substrate, and the extended portion is connected to an electrode for driving liquid crystal molecules of the liquid crystal layer. A wiring connection terminal is provided, and one of the pair of alignment marks is formed in a negative type at the corner of the black mask, and the other alignment mark is positioned diagonally with respect to the one alignment mark. It is preferable to dispose the alignment mark even in the liquid crystal display panel in which the connection terminal portion of the wiring is integrated into one edge extension portion of one substrate and the downsizing of the narrow frame is promoted. Light leakage from the installation area is remarkably suppressed to prevent deterioration in display quality, and the pair of alignment marks are separated as much as possible. It is possible to always accurately aligning the liquid crystal display panel because it location.

  Further, in the liquid crystal display panel of the present invention, the opposite surface is formed on the light reflecting surface in the opposite area of the opposite substrate with respect to the alignment mark formed in the black mask corner from which the black mask material is removed, that is, the negative type. It is preferable to dispose a light shielding film, which can reliably prevent light leakage from the alignment mark and ensure high display quality without light leakage, and more accurately because the alignment mark can be clearly seen. The liquid crystal display panel can be aligned.

Hereinafter, preferred embodiments of the present invention will be described.
FIG. 1 is a plan view showing an active matrix type liquid crystal display panel as one embodiment of the present invention, FIG. 2 is a schematic cross-sectional view showing the liquid crystal display panel taken along line II-II, and FIG. It is a partial enlarged plan view which expands and shows the Q section of the liquid crystal display panel.

  As shown in FIGS. 1 and 2, a pair of glass substrates 11 and 12 are joined together with a predetermined gap through a sealing material 13 arranged in a frame shape. A liquid crystal L is sealed in a region surrounded by the sealing material 13 between the pair of glass substrates 11 and 12. Then, one edge of one glass substrate 12 extends to the outer side opposite to the inner side where the liquid crystal L is sealed from the corresponding end face of the other glass substrate 11.

  A color filter layer 14 is provided on the surface (hereinafter referred to as the inner surface) of the small-size glass substrate 11 that is not extended and facing the large-size glass substrate 12. The color filter layer 14 includes red, green, and blue color filter elements 14r, 14g, and 14b arranged in a predetermined arrangement. A black mask layer 15 formed in a frame shape is provided outside the color filter layer 14 so as to surround the color filter layer 14. Therefore, the installation area of the color filter layer 14 becomes the display area Dv of the present liquid crystal display panel.

  The black mask layer 15 of this embodiment is formed by a seal printing method using resin black as a light shielding material. The outer end portion of the black mask layer 15 extends to about 0.05 mm before the end face of the glass substrate 11 as shown in FIG. 3 in order to prevent light leakage from the periphery outside the black mask.

  Thus, as shown in FIG. 1, the resin of the black mask material is formed in one corner portion of the four corners of the glass substrate 11 opposite to the side on which the extending portion 12a of the glass substrate 12 is formed. The first alignment mark 15a is formed by exposing the surface of the transparent glass substrate without depositing black. That is, the first alignment mark 15a is formed in a negative type. This negative type first alignment mark 15a is a mark that serves as a reference when positioning with the upper and lower cases Cu and Cd (see FIG. 2), and is formed in a perfect circle.

  Here, since the first alignment mark 15a is provided as a reference for alignment with the upper and lower cases Cu and Cd, the restrictions on the installation positions of the alignment holes hu1 and hd1 on the case side remain as they are. This is a positional constraint. In other words, the first alignment mark 15a is formed at a position where L = 1.0 to 1.5 mm enters from the end face of the substrate in accordance with manufacturing restrictions such as mold design related to the installation positions of the case side alignment holes hu1 and hd1. Needs to be performed, and the display area Dv becomes closer to that amount. Therefore, when this alignment mark for case alignment is formed in a positive type with a black mask material as in the prior art (see FIG. 6), the influence on the display quality of light leaking from the vicinity thereof becomes greater.

  However, since the first alignment mark 15a is formed in the negative type as described above, the degree of light leakage even if the first alignment mark 15a is formed at a position of about 1.0 to 1.5 mm from the end surface of the substrate. As compared with the conventional positive type, display quality deterioration due to light leakage from the alignment mark installation area is substantially eliminated.

  As shown in FIG. 1, in the non-display area Dn around the display area Dv, not only the first alignment mark 15 a described above, but also the position of the conductive member C that conductively connects between the glass substrates 11, 12 arranged facing each other. Various marks such as a member position mark 15b to be shown and a recognition number 15c for identifying the glass substrate 11 are formed in the same negative type as the first alignment mark 15a. By forming these various marks in a negative type, light leakage from these various mark arrangement areas is remarkably suppressed.

  As shown in FIG. 2, a planarization protective film 16 made of a transparent resin material covers the color filter layer 14 and the black mask layer 15 on the inner surface of the region surrounded by the sealing material 13 of the glass substrate 11. It is laminated uniformly. On the flat surface of the planarization protective film 16, a single sheet-like counter electrode 17 made of a transparent conductive film and an alignment film 18 for aligning liquid crystal molecules are sequentially stacked.

  On the other hand, a plurality of pixel electrodes 19 are arranged in a matrix on the inner surface of the region surrounded by the sealing material 13 in the large-size glass substrate 12 on the opposite side, and each pixel electrode 19 has a thin film transistor 20 as a switching element. Each is attached. The pixel electrode 19 and the thin film transistor 20 are uniformly covered, and an alignment film 21 is attached.

  A light shielding film 22 is disposed on the inner surface of the glass substrate 12 in an area facing the first alignment mark 15a on the glass substrate 11 side. The light shielding film 22 is made of a metal material such as chrome, and has a smooth finish so that the surface thereof is a light reflecting surface. As shown in FIG. 3, the light shielding film 22 also serving as the light reflecting film is formed in a perfect circle having a radius about 1.3 times larger than that of the first alignment mark 15a.

  By providing the light shielding film 22 described above, when a backlight is provided on the back side of the liquid crystal display panel (in this embodiment, the outer surface side of the large glass substrate 12) and transmissive display is performed, the irradiation light from the backlight is changed. It is possible to prevent the first alignment mark 15a from penetrating and leaking to the front side more remarkably than the case where the light shielding film 22 is not provided only by forming the first alignment mark 15a as a negative type.

  A driver chip 23 is mounted on the opposite surface of the extended portion 12a, which is the end of the glass substrate 12 opposite to the side where the light shielding film 22 is disposed, by COG (Chip On Glass). The driver chip 23 is a drive circuit element for driving liquid crystal molecules, outputs a signal voltage to each of the counter electrode 17 and the pixel electrode 19, and forms an electric field in the pixel portion where both the electrodes 17 and 19 face each other. The orientation of the liquid crystal molecules of the liquid crystal layer Lc sandwiched between the pixel portions is changed. The driver chip 23 and the thin film transistor 20 electrically connected to the counter electrode 17 and the pixel electrode 19 are electrically connected by various wirings 24 such as a source wiring and a gate wiring.

  Returning to FIG. 1, in the extended portion 12 a of the glass substrate 12, the opposite surface of the corner portion positioned diagonally with respect to the corner portion where the first alignment mark 15 a on the glass substrate 11 side is provided is Two alignment marks 25 are arranged. The second alignment mark 25 is used as a reference when aligning the liquid crystal display panel in a pair with the first alignment mark 15a. The second alignment mark 25 uses the same metal light-shielding material as the light-shielding film 22 and is used as a first alignment mark. It is formed in a perfect circle having the same size as the mark 15a.

  In this way, the first and second alignment marks 15a and 25 that are paired and serve as alignment reference marks for the liquid crystal display panel are positioned at the opposite corners of the liquid crystal display panel whose outer shape is rectangular, and are separated as much as possible. As a result, the alignment accuracy of the liquid crystal display panel is improved, and the liquid crystal display panel can be accurately installed at a predetermined position in the case in which the liquid crystal display panel is accommodated.

  That is, conventionally, in the one-edge extending type liquid crystal display panel as in the present embodiment, both of the pair of alignment marks as the alignment reference are provided on the substrate extending portion 12a. This is because, in order to arrange one of the pair of alignment marks at the corner of the substrate opposite to the substrate extension side, the corner portion of the black mask is scraped to form an alignment mark arrangement area in FIG. This is because the conventional glass substrate for a liquid crystal display panel shown in the figure is used, and light leaks from the exposed portion of the glass substrate in the arrangement area, resulting in deterioration of display quality. The distance between the pair of alignment marks installed in the substrate extension portion 12a is shorter than the case where the alignment marks are arranged at the diagonal positions of the liquid crystal display panel, and the alignment accuracy is reduced accordingly.

  However, in the present embodiment, since the glass substrate 11 of the liquid crystal display panel substrate according to the present invention is adopted, the alignment mark 15a can be arranged at a desired position around the display area while suppressing light leakage. The pair of alignment marks 15a, 25 are arranged at the maximum distance from the diagonal corners of the liquid crystal display panel, so that the liquid crystal display panel can be more accurately aligned.

  Further, since there is only one alignment mark of the second alignment mark 25 arranged on the substrate extension 12a, an area (mark) that must be secured in the substrate extension 12a in order to install the alignment mark. (Including neighboring areas) is reduced, and there is a margin in the routing area for various wirings, and wiring pattern design is facilitated and yield is improved.

Here, a procedure for housing the liquid crystal display panel configured as described above in a case will be described.
First, the liquid crystal display panel Lp is stored at a predetermined position in the lower case Cd. In this case, as shown by a two-dot chain line, the rear side glass substrate 12 is aligned through a pair of alignment holes hd1 and hd2 which are formed at positions diagonal to each other on the bottom plate forming the rectangle of the lower case Cd. The light shielding film 22 and the second alignment mark 25 provided on the inner surface are recognized by a camera or the like.

  FIG. 4A shows an appropriate arrangement in which the light shielding film 22 is completely included in the alignment hole hd1. On the other hand, as shown in FIG. 4B, the arrangement in which the light shielding film 22 protrudes from the alignment hole hd1 is an improper arrangement, and is adjusted to an appropriate arrangement by adjusting the position of the liquid crystal display panel. To do. The same applies to the alignment hole hd2 and the second alignment mark 25. In this camera recognition, an arrangement in which the whole of the perfect circular light shielding film 22 and the second alignment mark 25 corresponding to the perfect circular alignment holes hd1 and hd2 is completely included in the lower case Cd of the liquid crystal display panel Lp. Proper placement.

  In the proper arrangement state described above, the liquid crystal display panel Lp is fixed to the lower case Cd with a member such as a double-sided tape (not shown). In this case, the alignment holes hd1 and hd2 are formed to be larger than the corresponding light shielding film 22 and second alignment mark 25 by Δd in consideration of the respective manufacturing errors, and accordingly, the relative positions of the liquid crystal display panel Lp and the lower case Cd. Is allowed to deviate by a maximum based on the expected error Δd. The size of the allowable relative position deviation decreases as the distance between the light shielding film 22 and the second alignment mark 25 increases. In the present embodiment, since the light shielding film 22 and the second alignment mark 25 are provided at the corner located diagonally of the liquid crystal display panel Lp, the distance between them is maximized. Deviation within an allowable range in alignment with the case Cd is minimized, and the liquid crystal display panel Lp can be accurately installed at a predetermined position of the lower case Cd.

  Next, the upper case Cu is covered. In this case, the corresponding first and second alignment marks 15a and 25 are passed through the alignment holes hu1 and hu2 provided in the upper case Cu so as to correspond to the first and second alignment marks 15a and 25 of the liquid crystal display panel Lp. The upper case Cu is aligned while being visually recognized by a camera or the like. Similarly, the alignment holes hu1 and hu2 of the upper case Cu are formed larger than the first and second alignment marks 15a and 25 in consideration of manufacturing errors. Since it is installed at the corner portion located opposite to the liquid crystal display panel Lp and the distance between them is as large as possible, the displacement within the allowable range in the alignment of the upper case Cu with the liquid crystal display panel Lp is minimized. Thus, the upper case Cu can be more accurately placed at an appropriate position where the display window w (see FIG. 2) is aligned with the display area Dv of the liquid crystal display panel Lp.

  As described above, according to the liquid crystal display panel of the present embodiment, the alignment mark 15a provided at one corner around the display area of the substrate provided with the black mask is a negative pattern with respect to the black mask pattern on which the black mask material is not deposited. In addition, since a light-shielding film is provided in the area facing the alignment mark 15a of the opposite substrate, light leakage from the alignment mark 15a and its neighboring area is surely prevented, and deterioration of display quality due to this light leakage is eliminated. Is done.

  Also, a pair of case alignment alignment marks 15a and 25, one of which is the above-described alignment mark 15a, are respectively disposed at a pair of corner portions of the liquid crystal display panel Lp whose outer shape is a rectangle and positioned diagonally to each other. Thus, even in the liquid crystal display panel of the present embodiment in which the connection terminal portions of the wirings of both substrates are installed together on one edge extending portion of one substrate to promote the downsizing of the narrow frame, the pair of alignment marks 15a, The interval between 25 can be ensured as long as possible, and the alignment with respect to the case can be performed more accurately.

  Next, another embodiment of the present invention will be described with reference to FIG. In addition, the same code | symbol is attached | subjected about the component same as the said embodiment, and the description is abbreviate | omitted.

  The liquid crystal display panel of this embodiment is obtained by omitting the light shielding film 22 in the liquid crystal display panel described above. However, in the area facing the first alignment mark 15a on the inner surface of the rear glass substrate 12, that is, in the area where the light shielding film 22 is provided in the liquid crystal display panel described above, not only the light shielding film is provided, but also other wiring such as wiring It is necessary not to install patterns. This is because, if another pattern is formed in the facing area, it becomes difficult to visually recognize the first alignment mark 15a through the glass substrate 12 from the back side when aligning with the lower case Cd, which hinders alignment. Because it will come. Other configurations are the same as those of the liquid crystal display panel described above.

The procedure for housing the liquid crystal display panel of this embodiment in a case is as follows.
First, the liquid crystal display panel is installed at a predetermined position in the lower case Cd while being aligned. The alignment in this case is provided on the inner surface of the front glass substrate 11 through a pair of alignment holes hd1 and hd2 which are formed at positions diagonal to each other on the bottom plate of the lower case Cd, as indicated by a two-dot chain line. The first alignment mark 15a and the second alignment mark 25 provided on the opposite surface of the rear glass substrate 12 are recognized while being recognized by a camera or the like. In this camera recognition, when the entire first alignment mark 15a and the second alignment mark 25 corresponding to the perfect circle alignment holes hd1 and hd2 are completely included, the liquid crystal display panel Lp is placed in the lower case Cd. In contrast, the liquid crystal display panel Lp is fixed to the lower case Cd in the proper arrangement state.

  Next, when the upper case Cu is to be mounted, the corresponding first through the alignment holes hu1 and hu2 provided in the upper case Cu corresponding to the first and second alignment marks 15a and 25 of the liquid crystal display panel Lp2, respectively. The upper case Cu is aligned while recognizing the first and second alignment marks 15a and 25 by a camera or the like. The alignment holes hu1 and hu2 of the upper case Cu are formed to be larger than the first and second alignment marks 15a and 25 in consideration of manufacturing errors in the same manner as the alignment holes hu1 and hu2 of the lower case Cd. Since the first and second alignment marks 15a and 25 are installed at the corners located diagonally to the liquid crystal display panel Lp2 and the distance between them is maximized, the upper case Cu is aligned with the liquid crystal display panel Lp. The deviation within the allowable range is minimized, and the upper case Cu can be more accurately placed at an appropriate position where the display window w is aligned with the display area Dv of the liquid crystal display panel Lp2.

  As described above, also in the liquid crystal display panel of this embodiment, the alignment mark 15a provided at one corner around the display area of the substrate 11 provided with the black mask 14 is a negative pattern with respect to the black mask pattern on which the black mask material is not deposited. Therefore, even if a light shielding film is not provided on the counter substrate side, light leakage from the alignment mark 15a and the arrangement area in the vicinity of the alignment mark 15a can be suppressed to such an extent that the display is not adversely affected.

  In the present embodiment, the pair of alignment marks 15a and 25 are not only disposed diagonally to ensure the longest distance between them, but also the pair of alignment marks 15a and 25 are provided with the upper case Cu and the lower case. Since the common alignment mark for Cd is used, the alignment with respect to the case is more accurate than in the above-described embodiment in which the light-shielding film 22 is also an alignment mark.

In addition, this invention is not limited to embodiment mentioned above.
For example, the present invention is suitably applied not only to a one-edge-extending liquid crystal display panel but also to a two-edge-extending liquid crystal display panel in which each edge of a pair of substrates is extended in different directions. The

  In addition, the present invention is not limited to the active matrix type liquid crystal display panel as described above, but can be widely applied to various other liquid crystal display panels such as a simple matrix type using a black mask.

It is a top view which shows the liquid crystal display panel as one Embodiment of this invention. It is typical sectional drawing which cuts and shows the said liquid crystal display panel by the II-II line | wire. It is the elements on larger scale which expand and show the Q section of the liquid crystal display panel shown in FIG. It is explanatory drawing which shows the arrangement | positioning state of the light shielding film and alignment hole at the time of alignment with respect to the storage case of the said liquid crystal display panel, (a) has shown appropriate arrangement | positioning, (b) has shown improper arrangement | positioning, respectively. . It is typical sectional drawing corresponding to FIG. 2 which shows the liquid crystal display panel as other embodiment of this invention. It is a top view which shows the installation structure of the alignment mark in the conventional liquid crystal display panel.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate 2 Alignment mark 3 Black mask 4, 13 Sealing material 4 Photomask 11, 12 Glass substrate 14 Color filter layer 15 Black mask layer 15a First alignment mark 22 Light shielding film 25 Second alignment mark Dv Display area Dn Non-display area Cd Lower case Cu Upper case hd1, hd2 Alignment hole (lower case)
hu1, hu2 alignment holes (upper case)

Claims (4)

A transparent substrate of any one of a pair of substrates sandwiching a liquid crystal layer in a liquid crystal display panel,
A black mask is formed by depositing a light shielding material on substantially the entire surface excluding the pixel area in at least the display area of one main surface and the predetermined area around the display area,
A substrate for a liquid crystal display panel, wherein at least one of the predetermined areas is used as a reference alignment mark indicating the position of the substrate. A liquid crystal display panel in which a liquid crystal layer is sandwiched between a pair of substrates at least one of which is transparent and has a rectangular planar shape,
The transparent first substrate includes at least a pixel area in a display area in which a plurality of pixels are arranged on one main surface, and a predetermined area located at one substrate corner around the display area. A light shielding material is applied to substantially the entire surface to form a black mask, and the predetermined area is a first alignment mark serving as a reference indicating the position of the substrate,
A second alignment mark is formed at one corner of the substrate opposite to the first alignment mark on the second substrate disposed opposite to the first substrate at a corner of the substrate opposite to the first alignment mark. A liquid crystal display panel characterized by   One edge of the second substrate extends to the outer side opposite to the inner side where the liquid crystal layer is sandwiched with respect to the corresponding end surface of the first substrate, and the liquid crystal molecules of the liquid crystal layer extend to the extended portion. The liquid crystal display panel according to claim 2, wherein a connection terminal of a wiring connected to an electrode for driving is disposed, and the second alignment mark is disposed.   4. The light-shielding film having a light-reflecting surface formed on the light-reflecting surface is disposed in an area facing the first alignment mark on the surface facing the second substrate. 5. The liquid crystal display panel as described.

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