JP3880317B2 - Substrate, liquid crystal display device and electronic apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a substrate, a liquid crystal display device and an electronic apparatus, and more particularly to a technique suitable for use in a substrate having a conductive film such as a reflective film or an electromagnetic shielding film and an electrode.
[0002]
[Prior art]
FIG. 12 shows an example of a simple matrix drive type liquid crystal display device. The liquid crystal display device 200 shown in FIG. 12 has a pair of transparent rectangular substrates 220 and 221 with a sealing material 222 between them. It is constructed by interposing them.
In the configuration shown in FIG. 12, the substrate 220 is normally called the upper substrate, and the substrate 221 is usually called the lower substrate. As shown in FIG. 12, the substrate 221 stands on the front side and the substrate 220 on the back side, and both stand horizontally. In this state, the substrate 220 is formed taller than the substrate 221, the substrate 221 is formed to have a longer width than the substrate 220, and the substrate 220 and the substrate 221 are aligned with the bottom portion and the right side portion thereof. In addition to being integrated, a portion protruding above the substrate 221 is an extended end 223 of the substrate 220, and a portion protruding to the left side of the substrate 220 is an extended end 224 of the substrate 221. Yes.
[0003]
Between the substrates 220 and 221, a resin sealing material 222 is interposed between the substrates 220 and 221 along the corners of the overlapping portions of the substrates 220 and 221. The sealing material 222 includes an annular portion 222a arranged in a substantially rectangular annular shape along the peripheral edge portion of the overlapping portion of the substrates 220 and 221, and a right side surface of the substrates 220 and 221 at the right side central portion of the substrates 220 and 221. Extension portions 222b and 222b that are formed so as to be separated from each other in a substantially parallel manner and are formed with liquid crystal injection portions 226 on the right side of the substrates 220 and 221; and the injection portions 226 are closed. And a sealing portion 222c. In addition, a linear bank member 227 formed of a resin having a length approximately the same as the width of the injection portion 226 is slightly inside the injection portion 226 and is sandwiched between the substrates 220 and 221 and the right side surface of the substrate 220. They are provided almost in parallel.
[0004]
A large number of strip-shaped display electrodes are formed in parallel on the opposing surfaces of the substrates 220 and 221 inside the sealing material 222, respectively, and are formed on the large number of display electrodes 223 b and the substrate 221 formed on the substrate 220. A large number of display electrodes 224b are arranged to face each other at an angle of 90 degrees so as to form a matrix, and a rectangular electrode slightly narrower than the annular sealing material 222 is formed inside the sealing material 222. Region 230 is formed.
The display electrodes 223b and 224b are made of a transparent conductive material such as indium tin oxide (hereinafter referred to as ITO).
In the extended end portion 223 of the substrate 220, on the surface on the substrate 221 side, the above-described extraction electrodes 223a... Drawn from the many display electrodes 223b are aligned and formed, and the extended end portion 224 of the substrate 221 is formed. In FIG. 2, the lead electrodes 224a drawn from the display electrodes 224b are aligned on the surface on the substrate 220 side. These lead electrodes 223a and 224a are used for mounting a driving IC of a liquid crystal display device.
Further, an overcoat layer and an alignment film are stacked on the opposite surface side of the substrates 220 and 221 in addition to the electrode layer, and in the case of a structure for performing color display, a color filter is further provided. Description of these parts is omitted.
[0005]
A metal reflective film 231 made of vapor-deposited Al or the like is formed on almost the entire outer surface side of the substrate 221 (lower substrate), and the metal reflective film 231 is formed only in a portion corresponding to the electrode formation region 230. In addition, an unformed portion 231b of the metal reflection film is formed in a portion corresponding to the lead electrode forming region of the substrate 221 in the surrounding area.
[0006]
When manufacturing such a substrate 220, after forming the metal reflective film 231, the extraction electrode 223a, and the display electrode 223b, in the step of forming the alignment film, between the printing roll and the printing metal stage. Therefore, the substrate 220 is strongly pressed against the printing metal stage.
Furthermore, it is necessary to peel off the substrate 220 from the metal stage in order to transport the substrate 220 in a subsequent process. For this reason, the board | substrate 220 was peeled from the metal stage with the lifter pin etc. which are located in the four corners.
[0007]
[Problems to be solved by the invention]
However, in the process of peeling the substrate 220 from the metal stage, the display electrode 223b is damaged by the discharge caused by the charged electric charge, and a display defect occurs in the display region, resulting in a defective product. There was a problem.
[0008]
The inventors of the present application have searched for the cause of this discharge, and in the alignment film printing process, the substrate 220 and the metal stage are pressed and adhered to each other by the printing roll, and the contact ratio between the substrate 220 and the metal stage is increased. Thus, it has been found that when the substrate 220 is peeled off for transport to the subsequent process, the amount of electric charge charged on the substrate 220 is increased.
Further, it has been found that the charging potential on the substrate 220 varies from lot to lot as shown in FIG. 9, and that this discharge is likely to occur when the value of the charge amount is high.
[0009]
The inventor of the present application installs an EMI (electromagnetic induced) locator in order to detect the above-mentioned discharge, and measures the electromagnetic wave generated by the discharge to identify the discharge generation process and consider the charging model. And tried to identify the cause. Then, since the substrate 220 is charged, when the metal stage is peeled off, only the substrate 220 in contact with the lifter pin is separated from the metal stage and the substrate 220 itself is bent, and the central portion of the substrate 220 is It has been found that a discharge occurs due to a potential difference between the display electrodes 223b and 223b in order to be in contact with the metal stage.
In other words, the cause of electrostatic breakdown could be determined.
[0010]
Furthermore, as a result of earnest pursuit, the inventors of the present application have determined that the potential difference between the adjacent electrodes located at the site damaged by electrostatic discharge generated due to static electricity generated on the back surface of the substrate is the area of the reflective film. It has been found that the ratio varies depending on the ratio of the area of the electrode that does not overlap the reflective film.
[0011]
The present invention has been made in view of the above circumstances, and intends to achieve the following object.
(1) Prevent the occurrence of electrostatic discharge.
(2) To prevent the occurrence of defects in the electrode due to electrostatic discharge.
(3) Prevent display defects caused by electrostatic discharge.
(4) To provide a substrate that prevents the above-mentioned defect from occurring.
(5) To provide a liquid crystal display device free from the above display defect.
(6) To provide electronic equipment that prevents the above-mentioned defects.
[0012]
[Means for Solving the Problems]
The substrate of the present invention includes a conductive coating film made of a conductive material on a substrate made of an insulating material, and a plurality of wirings formed in a film shape with respect to the coating film via the insulating film. ,
In the area S1 of the conductive coating film and the area S2 of the portion of the wiring that does not overlap the conductive coating film, the ratio S2 / S1 of these areas is set to 0.001 or less. Solved the problem.
In the liquid crystal display device of the present invention, the first substrate of the pair of substrates that are disposed to face each other with the liquid crystal layer interposed therebetween and that has at least a predetermined pattern of electrodes on the surface on the liquid crystal layer side includes at least a display region. A conductive reflective film covering the
In the first substrate, the ratio S2 / S1 of these areas is set to 0.001 or less in the area S1 of the reflective film and the area S2 of the portion of the front electrode that does not overlap the reflective film. The above problem was solved.
In the electronic device of the present invention, an electromagnetic shielding film (conductive coating film) made of a conductive material on a substrate made of an insulating material, and a plurality of films formed on the electromagnetic shielding film through the insulating film. Wiring of,
In the area S1 of the electromagnetic shielding film and the area S2 of the portion of the wiring that does not overlap with the electromagnetic shielding film, the ratio S2 / S1 of these areas is set to 0.001 or less. Settled.
In the present invention, the ratio S2 / S1 is preferably set to 0.0001 or less.
In the present invention, it is more preferable that all the wirings (electrodes) overlap with the conductive coating film (electromagnetic shielding film or reflection film).
[0013]
In the substrate of the present invention, the area S2 of the portion that does not overlap the conductive coating film in any one of the wirings on the substrate, the ratio S2 / S1 to the area S1 of the conductive coating film is 0.001. By setting it to be as follows, it becomes possible to suppress the potential difference between the wirings caused by static electricity generated at the time of manufacturing, etc., thus preventing the occurrence of electrostatic discharge between the wirings. The yield rate can be improved by lowering the defect rate, which is the ratio of the number of products in which wiring defects due to discharge occur to the total number of products.
Specifically, when the ratio S2 / S1 is set to 0.001 or less, the defect rate represented by (number of cells in which even one wiring defect due to discharge has occurred) / (total number of manufactured cells) is 3%. It is possible to:
Here, the wiring defect is not limited to a defective wiring, but means a state in which the structure around the wiring is affected by electrostatic discharge and the desired performance is not exhibited.
[0014]
Furthermore, since the ratio S2 / S1 is set to 0.0001 or less, the defect rate can be 0.5%, which is even more preferable.
[0015]
In addition, when all the wirings (electrodes) overlap with the conductive coating film (electromagnetic shielding film or reflective film), that is, by setting S2 = 0, the defect rate due to display defects caused by electrostatic discharge is set to 0%. It is more preferable because it is possible.
[0016]
In the liquid crystal display device of the present invention, the area S2 of the portion that does not overlap the reflective film in any one of the electrodes on the substrate is set to a ratio S2 / S1 with respect to the area S1 of the reflective film of 0.001 or less. Since it is possible to suppress the potential difference between the electrodes caused by static electricity generated during manufacturing, etc., it is possible to prevent the occurrence of electrostatic discharge between the electrodes and discharge It is possible to prevent an increase in the defective rate, which is a ratio of the number of products in which display defects are caused to the total number of products, and improve the yield.
Specifically, when the ratio S2 / S1 is set to 0.001 or less, the defect rate indicated by (number of cells in which even one display defect due to discharge has occurred) / (total number of manufactured cells) is 30%. It is possible to:
[0017]
In the electronic apparatus according to the present invention, the area S2 of the portion that does not overlap the electromagnetic shielding film in any one of the wirings on the substrate has a ratio S2 / S1 to the area S1 of the electromagnetic shielding film of 0.001 or less. Since it becomes possible to suppress the potential difference between the wirings caused by static electricity generated during manufacturing, etc., it is possible to prevent electrostatic discharge from occurring between the wirings. It is possible to reduce the defect rate, which is a ratio of the number of products in which wiring defects due to discharge occur to the total number of products, and to improve the yield.
[0018]
According to the above-mentioned substrate, liquid crystal display device, and electronic device, the area S1 of the conductive coating film (reflection film, electromagnetic shielding film) and the wiring (electrode) without changing the manufacturing process itself and each condition at that time Among these, by setting the area S2 of the portion that does not overlap with the conductive coating film, it is possible to prevent discharge between wires (electrodes) without using means such as remodeling of manufacturing equipment, and to cause defects caused by discharge The rate can be reduced and the yield can be improved. Here, a portion of the wiring (electrode) that does not overlap with the conductive coating film means a portion that does not overlap with the conductive coating film in a plan view and does not overlap with the conductive coating film. It means that.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
[Embodiment 1]
Hereinafter, a substrate and a liquid crystal display device according to a first embodiment of the present invention will be described with reference to the drawings.
1 is a cross-sectional view showing a liquid crystal display device according to the present embodiment, FIG. 2 is a cross-sectional view showing a common substrate in the liquid crystal display device of FIG. 1, FIG. 3 is a plan view showing the common substrate, and FIG. FIG.
[0020]
The liquid crystal display device of this embodiment is a reflection type simple matrix type liquid crystal display device. In the figure, reference numeral 1 denotes a first substrate, 2 denotes a reflective film, and 3 denotes a display region.
In this liquid crystal display device, basically, a liquid crystal layer 45 made of STN (Super Twisted Nematic) liquid crystal or the like is sandwiched between a pair of substrates 1 and 31 made of a glass substrate or the like.
[0021]
As shown in FIG. 1, on the surface of the lower substrate (first substrate) 1 facing the upper substrate 31, a reflective film (conductive coating film) 2, red (R), A color filter layer 21 composed of color pixels such as green (G) and blue (B) and a light shielding layer (black matrix) is sequentially stacked, and a plurality of electrodes (wirings) 7 are formed thereon via an overcoat layer 11. Is formed, and an alignment film 43 is further formed thereon to form a common substrate (base body) 47. The common substrate 46 is a component corresponding to the lower substrate 221 shown in FIG.
Similarly, a plurality of electrodes 37 extending in a direction orthogonal to the display electrodes 4 of the lower substrate 1 are formed on the surface facing the lower substrate 1 of the upper substrate 31 via the overcoat film 41, The segment substrate 46 is formed by sequentially laminating the alignment layers 42. The segment substrate 46 is a component corresponding to the upper substrate 220 shown in FIG.
[0022]
A portion of the pair of glass substrates that are spaced apart from each other, that is, the common substrate 47 and the segment substrate 46 are bonded via a sealing material 44 and sandwiched between the pair of substrates 46 and 47 to form the display region 3. The liquid crystal 45 is filled in a cell surrounded by a sealing material 44 formed around the periphery of the liquid crystal.
Further, in order to make the cell gap of the liquid crystal cell uniform in the liquid crystal layer 45, a large number of spherical spacers made of silicon dioxide, polystyrene or the like are arranged. Optical elements such as plates are provided, but these are omitted in the drawing.
[0023]
The reflection film 2 is made of silver or aluminum that reflects light, and external light such as sunlight incident from the upper substrate 31 side (observer side) is transmitted through the liquid crystal layer 45 and reflected by the reflection film 2. The liquid crystal layer 45 and the upper substrate 31 are transmitted through the liquid crystal layer 45 and the upper substrate 31, and can be displayed.
The reflective film 2 is provided not only on the display area 3 but also on the outer side of the reflective film 2 so as to overlap with later-described lead wires 6 and terminal portions 5, and the range in which the reflective film 2 is provided is set as described later.
[0024]
As shown in FIG. 1, the color filter 21 includes a red (R), green (G), and blue (B) colored layer and a light shielding layer (black matrix) that shields adjacent colored layers. In the liquid crystal display device according to the present embodiment, a portion where the display electrode 4 and the display electrode 34 intersect is a pixel, and one of the red, green, and blue colored layers corresponding to each pixel. Is arranged, and one display is possible with three pixels displaying red, green, and blue. The overcoat film (planarization film) 11 is made of an organic film or the like, and is provided to planarize the surface of the lower substrate 1 on which the color filter 21 is formed.
[0025]
The alignment films 42 and 43 are made of an alignment polymer such as polyimide, and the surfaces thereof are rubbed in a predetermined direction using a cloth or the like according to the alignment state of the liquid crystal layer 45 when no electric field is applied.
[0026]
A plurality of electrodes (wirings) 7 and 37 made of ITO (indium tin oxide) or the like are formed on the surface of the lower substrate 1 and the upper substrate 31 on the liquid crystal layer 45 side. By applying a predetermined voltage to the liquid crystal, the alignment state of the liquid crystal is changed, and the structure can be displayed by optically identifying this. These electrodes 7 and 37 are formed in stripes orthogonal to each other as the display electrodes 4 and 34 in the display region 3, and a portion where these display electrodes 4 and 34 intersect is a pixel, and a liquid crystal is used for each pixel. The system driven from the outside is adopted.
[0027]
The display electrode 4 is formed in a stripe shape inside the display area 3, and each terminal located outside the display area 3 via an extraction wiring (electrode) 6 whose end is located outside the display area 3. It is formed so as to be connected to the part (electrode) 5. These display electrodes 4, lead wires 6, and terminal portions 5 constitute electrodes 7.
The lead wirings 6, 6... Are set to have a width dimension W1 of 70 μm and a spacing dimension P1 of 20 μm, respectively.
[0028]
As shown in FIG. 3, the plurality of display electrodes 4, 4... In the display area 3 are divided into four blocks, and each is connected to terminal portions 5, 5 collected in different parts.
That is, the display electrodes 4, 4... Located in the display area 3 A located at the right end in FIG. 3 are respectively terminal portions located in the lower right corner of the lower substrate 1 by the extraction wirings 6, 6. Connected to 5, 5... Similarly, the display electrodes 4, 4... Located in the display region 3 B located second from the right in FIG. 3 are respectively connected to the upper right corner of the lower substrate 1 by the lead wires 6, 6. It is connected to the terminal portions 5, 5.
Similarly, the display electrodes 4, 4... Located in the display area 3 C located second from the left in FIG. 3 are respectively connected to the lower left corner of the lower substrate 1 by the lead wires 6, 6. It is connected to the terminal portions 5, 5. Similarly, the display electrodes 4, 4... Located in the display region 3 D located on the left bridge in FIG. 3 are located at the upper left corner of the lower substrate 1 by the lead wires 6, 6. Connected to the terminal portions 5, 5.
[0029]
The electrode 7 on the lower substrate 1 is connected to the electrode 35 on the upper substrate 31 by a sealing material 44 made of an anisotropic conductive material in the terminal portion 5 located outside the display region 3. A driving circuit for supplying a signal to the display electrodes 4 and 34 of each substrate is mounted on the electrode 35 positioned outside the display area on the upper substrate 31 and the electrode 37 of the upper substrate 31, respectively. The driving circuit and each transparent electrode are electrically connected.
[0030]
In this way, the terminal portions 5 and 5 provided at the four corners of the lower substrate 1 are connected to the driving circuit via the sealing material 44 made of an anisotropic conductive material and the electrode 35 of the upper substrate 31. This eliminates the need for the extended end 224 provided on the lower substrate 221 shown in FIG. 12, making it possible to connect (mount) the drive circuit only to the upper substrate, etc. And the mounting of the driving circuit on the substrate can be facilitated.
[0031]
Next, the range in which the reflective film 2 is provided will be described.
[0032]
As shown in FIGS. 3 and 4, the reflective film 2 is provided up to a position outside the display region 3, but the range is set according to the relationship with the arrangement of the electrodes 7.
That is, the area S1 of the reflective film 2 is smaller than the area S2 of the portion of the electrodes 7, 7,... On the lower substrate 1 that does not overlap with the reflective film 2 in plan view. The area ratio S2 / S1 is set to be 0.001 or less.
[0033]
In FIG. 4, as an example of the area S <b> 2 of the electrode 7 that does not overlap the reflective film 2, a region that becomes S <b> 2 is shown for the electrode 7 that has the lead-out wiring 6 positioned on the outermost side of the substrate 1. . That is, in this example, the length of the portion of the electrode 7 passing through the display region 3A in FIG. 3 that does not overlap the reflective film 2 is the maximum, that is, the product of the width W1 of the electrode 7 and the total extension. The area S2 having the largest area, that is, the ratio S2 / S1 to the area of the reflective film 2 is the largest.
Therefore, if S2 shown in the drawing meets the above condition, the other electrodes 7, 7... Of the display area 3A all satisfy the above condition.
Similarly, in the display regions 3B, 3C, 3D, the range in which the reflective film 2 is provided is set so that the value of the area S2 satisfies the above-described condition in all the electrodes 7, 7,.
[0034]
Here, outside the display area 3 of the lower substrate 1, as shown in FIG. 3, an area D in which a dummy electrode that is not connected to the electrode 7 passing through the display area 3 exists is provided. Since the dummy electrode existing in the region D is considered not to be involved in the electrostatic discharge between the display electrodes 4 and 4 extending in the display region 3, in the present embodiment, the condition of S2 / S1 is satisfied. It does not need to be satisfied and is excluded from the above conditions.
[0035]
In the liquid crystal display device of the present embodiment, the area S2 of the portion that does not overlap the reflective film 2 in any one of the electrodes 7, 7,... On the lower substrate 1 is set to the area S1 of the reflective film 2. By setting the ratio S2 / S1 to be 0.001 or less, in the manufacturing process of the common substrate 47, the lower substrate on which the shape transfer film 12, the reflective film 2, the overcoat film 11, and the electrode 7 are formed. In contrast, when the alignment film 43 is printed as the next step, the lower substrate 1 to be the common substrate 47 is placed on a metal stage, and the lower substrate 1 is pressed by the metal stage and the printing roller. When the substrate 1 is peeled from the metal stage, it is possible to suppress the potential difference between the electrodes 7, 7.
[0036]
This makes it possible to prevent electrostatic discharge from occurring between the electrodes 7 when the lower substrate 1 is peeled off from the metal stage for the next step of printing the alignment film 43. . Therefore, the defect rate at which display defects occur due to damage (wiring defects) of the electrodes 7 and 7 due to discharge or insulation failure of the overcoat film 11 can be reduced to 3% or less.
Here, the defect rate is represented by the ratio of the number of cells in which display defects due to electrostatic discharge occur to the total number of manufactured cells.
[0037]
In addition, according to the liquid crystal display device of the present embodiment, the reflective film 2 is merely extended outside the display region without changing the manufacturing process itself and the conditions at that time, that is, below the reflective film 2. Only by setting the formation position with respect to the side substrate 1, the discharge between the electrodes 7, 7... Can be prevented without using means such as remodeling of manufacturing equipment, and the yield rate can be reduced by reducing the defect rate due to electrostatic discharge. Can be improved.
[0038]
In the present embodiment, the outline of the reflective film 2 is rectangular, but the shape is not limited to this shape, and various shapes are possible within the scope of the present invention. For example, as shown in FIG. 14, in each of the display areas 3A, 3B, 3C, 3D, the length of the portion where each electrode 7 does not overlap with the reflective film 2 is made equal, or each electrode 7 , 7, it is also possible to reduce the variation in the ratio of S2 / S1.
[0039]
[Embodiment 2]
Hereinafter, a second embodiment of a substrate and a liquid crystal display device according to the present invention will be described with reference to the drawings.
[0040]
In the present embodiment, the difference from the first embodiment shown in FIGS. 1 to 4 is the arrangement of the electrode 7 with respect to the reflective film 2, and the other corresponding components are denoted by the same reference numerals. Description is omitted.
FIG. 5 is a plan view showing a common substrate in the liquid crystal display device of the present embodiment.
[0041]
In the common substrate 47 of the present embodiment, the arrangement of the reflective film 2 with respect to the lower substrate 1 is substantially the same as that of the first embodiment shown in FIGS. 3 and 4, and as shown in FIG. In the electrodes 7 and 7, the lead-out wirings 6 ′, 6 ′,.
In other words, the portions of the electrodes 7, 7... That do not overlap the reflective film 2 are only the terminal portions 5, 5. This is realized, for example, by setting the width dimension W1 to 50 μm in each of the lead wires 6 ′, 6 ′.
[0042]
The area S1 of the reflection film 2 is smaller than the area S2 of the portion of the electrodes 7, 7,... On the lower substrate 1 that does not overlap with the reflection film 2 in an arbitrary manner. The area ratio S2 / S1 is set to be 0.0001 or less.
[0043]
Compared to the first embodiment shown in FIG. 4, only the portion of the terminal portion 5 is defined as S <b> 2 in the present embodiment in the area S <b> 2 of the electrode 7 that does not overlap the reflective film 2. Is shown. That is, in this example, in the electrodes 7 and 7 that pass through the display regions 3A, 3B, 3C, and 3D in FIG. 5, all areas S2 that do not overlap the reflective film 2 are set to be equal. That is, the ratio S2 / S1 with respect to the area of the reflective film 2 is set to the same value of 0.0001.
[0044]
In the liquid crystal display device of this embodiment, the same effects as those of the first embodiment described above can be obtained, and any one of the electrodes 7 and 7 on the lower substrate 1 can be combined with the reflective film 2. By setting the area S2 of the non-overlapping portion so that the ratio S2 / S1 to the area S1 of the reflective film 2 is 0.0001 or less, in the manufacturing process of the common substrate 47, the shape transfer film 12, the reflective film 2. When printing the alignment film 43 as the next process on the lower substrate on which the overcoat film 11 and the electrode 7 are formed, the lower substrate 1 to be the common substrate 47 is placed on a metal stage. After pressing the lower substrate 1 with the printing roller and then peeling the lower substrate 1 from the metal stage, the potential difference between the electrodes 7, 7. Theft is possible.
[0045]
Thereby, when the lower substrate 1 is peeled off from the metal stage for the next process of printing the alignment film 43, it is possible to further prevent the occurrence of electrostatic discharge between the electrodes 7, 7. Become. Therefore, the defect rate at which display defects occur due to damage to the electrodes 7 and 7 due to discharge or insulation failure of the overcoat film 11 can be reduced to 0.5% or less.
[0046]
In the present embodiment, the value of the area ratio S2 / S1 is set to 0.0001 by making the width dimension of the lead wires 6 ′, 6 ′... Smaller than the value of the first embodiment. In addition, the value of the area ratio S2 / S1 can be changed by changing the shape of the reflective film 2.
[0047]
[Embodiment 3]
Hereinafter, a third embodiment of a substrate and a liquid crystal display device according to the present invention will be described with reference to the drawings.
[0048]
In the present embodiment, the difference from the first embodiment shown in FIGS. 1 to 4 is the arrangement of the reflective film 2 ′ with respect to the lower substrate 1, and other corresponding components are denoted by the same reference numerals. Therefore, the description is omitted.
FIG. 6 is a plan view showing a common substrate in the liquid crystal display device of the present embodiment.
[0049]
In the common substrate 47 of the present embodiment, the reflective film 2 ′ is set so as to have substantially the same area as the lower substrate 1, and as shown in FIG. And all are set to overlap.
That is, the electrodes 7, 7... Are set so that there is no portion that does not overlap the reflective film 2 ′, that is, the electrodes 7, 7 do not have a portion that does not face the reflective film 2.
[0050]
The area S1 of the reflective film 2 ′ is such that, in any one of the electrodes 7, 7,... On the lower substrate 1, the area S2 of the portion that does not overlap with the reflective film 2 in plan view. The area ratio S2 / S1 is set to 0.
[0051]
In the liquid crystal display device of this embodiment, the same effects as those of the first embodiment described above can be obtained, and any one of the electrodes 7 on the lower substrate 1 can overlap with the reflective film 2 ′. In the manufacturing process of the common substrate 47, the shape transfer film 12 and the reflective film 2 are formed by setting the area S2 of the unexposed portion to 0 and setting the ratio S2 / S1 to the area S1 of the reflective film 2 ′ to be 0. 'When the alignment film 43 is printed as the next process on the lower substrate on which the overcoat film 11 and the electrode 7 are formed, the lower substrate 1 to be the common substrate 47 is placed on a metal stage. When the lower substrate 1 is pressed with the printing roller and then peeled off from the metal stage, it is possible to eliminate a potential difference between the electrodes 7, 7. Become.
[0052]
Thereby, when the lower substrate 1 is peeled off from the metal stage for the next process of printing the alignment film 43, it is possible to completely prevent the occurrence of electrostatic discharge between the electrodes 7, 7. It becomes. Therefore, the defect rate at which display defects occur due to breakage of the electrodes 7 and 7 due to discharge or insulation failure of the overcoat film 11 can be reduced to 0%.
[0053]
In each of the above embodiments, the color liquid crystal display device and the substrate thereof have been described. However, as shown in FIG. 7, a configuration without the color filter layer 21 is also possible.
[0054]
[Embodiment 4]
Hereinafter, a fourth embodiment of a substrate and an electronic apparatus according to the present invention will be described with reference to the drawings.
FIG. 10 is a diagram illustrating an example of an electronic device according to the present invention, and FIG. 11 is a perspective view illustrating a main part of the stacked structure of the electronic device illustrated in FIG.
[0055]
The electronic device in the present embodiment is a pad type data input device 100 used for a computer or the like. As shown in FIG. 10 and FIG. 11, an electrode pattern is formed and a sensor substrate 102 having a through hole is provided. A printed wiring board (hereinafter referred to as PCB) 120 as a first board having a wiring pattern on one side and an electromagnetic shielding film 20 for shielding electromagnetic waves on the opposite side to the sensor board 102 is insulated. A laminated substrate bonded through layers is used.
[0056]
The sensor substrate 102 is made of a resin sheet such as polyethylene terephthalate (PET), and a plurality of X electrodes 112 are formed in parallel on the surface of the sensor substrate 102 as shown in FIG. A plurality of Y electrodes 113 are formed in parallel. As shown in FIG. 11, the X electrode 112 and the Y electrode 113 are arranged in a matrix and intersect with each other, and an input point is formed at the intersection.
[0057]
In the data input device 100, coordinate information is input by changing the electrostatic capacitance between the X electrode 112 and the Y electrode 113 at the input point.
[0058]
As shown in FIG. 11, an end portion 117 of the Y electrode 113 and a dummy electrode 114 facing the end portion 117 are formed on the edge portion of the sensor substrate 102 parallel to the X electrode 112. On the other hand, an end portion 116 of the X electrode 112 and a dummy electrode 113 a facing the end portion 116 are formed at an edge portion of the sensor substrate 102 parallel to the Y electrode 113.
[0059]
A through hole 135 penetrating the sensor substrate 102 is formed in a region where the end portion 117 of the Y electrode 113 and the dummy electrode 114 are opposed to each other. Similarly, the end portion 116 of the X electrode 112 and the dummy electrode 113a A through hole 136 penetrating the sensor substrate 102 is formed in a region facing each other.
[0060]
Further, as shown in FIG. 11, an air hole 102a constituting a vertical passage of the air vent passage is formed outside the through hole 135 at the edge parallel to the X electrode 112 of the sensor substrate 102.
[0061]
Furthermore, as shown in FIG. 11, a ground pattern 118 is integrally formed at the edge of the surface of the sensor substrate 102. The end portion of the ground pattern 118 is exposed to the outside of the multilayer substrate as shown in FIG. The frame ground 115 is for releasing static electricity to the grounding portion.
[0062]
In order to increase the resolution, it is preferable that the line width of the Y electrode 113 is larger than the line width of the X electrode 112. The thickness of the sensor substrate (resin sheet) 102 is preferably about 250 to 800 μm.
[0063]
As shown in FIG. 11, a resist film 106 made of, for example, an epoxy resin is laminated on the upper surface of the sensor substrate 102, and a similar resist film is laminated on the lower side.
[0064]
As shown in FIG. 11, the edge portion parallel to the X electrode 112 of the resist film 106 provided on the surface side (the upper side in the drawing) of the sensor substrate 102 and serving as an insulating layer on the surface side of the sensor substrate 102 An air hole 124a that constitutes a part of the vertical passage of the air vent passage, and a protruding portion 124 that protrudes outward so as to surround the vertical passage are formed. Further, the resist film 106 exposes the end portion 116 of the X electrode 112, exposes the position facing the through hole 136 and the dummy electrode 114 facing the end portion 117 of the Y electrode 113, and A notch hole 125 is provided at a position facing the through hole 135.
[0065]
On the other hand, the dummy electrode 113a of the sensor substrate 102 is exposed on the resist film that is an insulating layer provided on the back side (the lower side in the drawing) of the sensor substrate 102, and is formed at a position facing the through hole 136. The cutout hole, the end 117 of the Y electrode 113 are exposed, a circular hole formed at a position facing the through hole 135, and a lower side of the air hole 102a provided in the sensor substrate 102 from the circular hole. And a lateral passage of an air passage formed continuously to the position.
[0066]
A ground layer is formed on the lower surface of the resist film. This ground layer is formed by bonding or printing a Cu foil or an Ag-based paste on an insulating sheet such as PET. The ground layer is provided with an air hole that constitutes a part of the vertical passage, and a notch hole formed at a position facing the circular hole and the notch hole provided in the resist film. The notch hole is formed continuously with a circular hole or the notch hole. Further, an adhesive layer is formed on the lower surface of the ground layer. The material of the adhesive layer is preferably a hot melt adhesive. The adhesive layer is formed on the surface of the PCB 120 or the surface of the ground layer on the sensor substrate 102 side by a printing method or the like.
[0067]
As shown in FIG. 11, the PCB 120 serving as the first substrate is a single-sided substrate in which a wiring pattern is formed only on the back surface (the lower side in the drawing). As shown in FIG. 11, lands 182 are formed on portions of the back surface of the PCB 120 facing the dummy electrode 113 a and the end portion 117 of the Y electrode 113 of the sensor substrate 102. A through hole 123 is formed at the position of the land 182. That is, as shown in FIG. 11, the patterns (i), (ii), (iii)... Of the sensor substrate 102 and the lands (i), (ii), (iii). The patterns (1), (2)... Of the sensor substrate 102 and the lands (1), (2)... On the PCB 20 side are through holes 136 and 123. Via each other.
[0068]
Further, a wiring pattern extending from the land 182 is formed on the back surface of the PCB 120, and an electromagnetic shielding film 20 is provided on the entire surface. An electronic component such as an IC is mounted on the wiring pattern so as to be electrically connected.
[0069]
The electromagnetic shielding film 20 is made of, for example, a metal such as Al, and shields electromagnetic waves radiated from electronic parts and the like located on the back side of the data input device 100 to maintain the operational stability of the data input device 100. And formed on the entire surface of the PCB 120. In the figure, the sensor substrate 102 and the printed wiring board 120 are separated from each other for the sake of explanation.
[0070]
As shown in FIG. 11, the sensor substrate 12 and the PCB 120 are laminated, and a conductive material is filled from the through holes 135 and 136 of the sensor substrate 102 into the laminated body bonded via the adhesive layer.
As the conductive material, a conductive resin, for example, a material in which a conductive filler such as Ag is mixed in a thermosetting resin such as epoxy and phenol or polyester can be used. The conductive material is filled with a squeegee at positions where the through holes 135 and 136 shown in FIG. 11 are formed on the surface of the sensor substrate 102.
Then, by the conductive material, the end portions 117 of the X electrode 112 and the Y electrode 113 of the sensor substrate 102 and the land 182 on the back surface of the PCB 120 are electrically connected to form a laminated substrate.
[0071]
In the data input device 100 of this embodiment, a face sheet that directly contacts a finger when inputting data is laminated on the upper surface of the resist film 106 of the laminated substrate.
In the data input device 100 configured as described above, the X electrode 112 and the Y electrode 113 formed on the sensor substrate 102 are slid by lightly rubbing the finger on the face sheet by the operator. A portion of the lines of electric force going from to the Y electrode 113 is absorbed by the operator's finger. As a result, a phenomenon occurs in which the lines of electric force absorbed by the Y electrode 113 decrease and the capacitance changes. Then, based on the current output value of the sensor substrate 102 that changes in accordance with the change in the capacitance, the position of the coordinate where the finger is pressed is detected.
[0072]
In such a data input device 100, since there is no portion where the Y electrode 113 does not overlap the electromagnetic shielding film 20, the value of S1 / S2 is 0 as in the third embodiment shown in FIG. Here, the electromagnetic shielding film 20 corresponds to the reflective film 2 ′, and the Y electrode 113 corresponds to the electrode 7.
[0073]
In the data input device 100 as the electronic apparatus of the present embodiment, the same effects as those of the third embodiment described above can be achieved. That is, by setting the area S2 of a portion of the Y electrode 113 that does not overlap the electromagnetic shielding film 20 to a ratio S2 / S1 with respect to the area S1 of the electromagnetic shielding film 20, the manufacturing process, etc. The defect rate at which wiring defects due to breakage of the Y electrodes 113 and 113 caused by electrostatic discharge, etc. are prevented by suppressing the potential difference between the Y electrodes 113 and 113 caused by static electricity generated in Can be reduced to 0 percent.
[0074]
[Example]
Hereinafter, as examples of the present invention, the ratio of area S2 / S1 was changed as follows, and the defect rate at that time was measured.
[0075]
Example 1
First, as Example 1, a structure equivalent to that of the first embodiment shown in FIG. In the first embodiment, the area ratio S2 / S1 is set to 0.001 or less.
Specific dimensions of each part are as follows.
[0076]
Dimensions of the reflective film 2 corresponding to S1: 4.3 cm × 3.6 cm
Among the lead wires 6 that are part of S2, the longest one, that is, the lead wire 6 located on the outermost side in the display area 3C, the width dimension of the lead wire 6a inclined as shown in FIG. Length 0.36cm
In FIG. 3, the lead wire 6b extending in the left-right direction has a width dimension of 70 μx and a length of 1.1 cm.
Terminal part 5 width 50 μm × 0.3 cm
[0077]
(Example 2)
Next, as Example 2, a structure equivalent to that of the second embodiment shown in FIG. In the second embodiment, the area ratio S2 / S1 is set to 0.0001.
Specific dimensions of each part are as follows.
[0078]
Dimensions of the reflective film 2 corresponding to S1: 4.3 cm × 3.6 cm
Of the electrode 7 that is a part of S2, the terminal 5 has a width of 50 μm × 0.3 cm.
[0079]
(Example 3)
Next, as Example 3, a structure equivalent to that of the third embodiment shown in FIG. In Example 3, the reflective film 2 is provided so as to cover all parts of the substrate 1.
[0080]
(Comparative example)
And as a comparative example, the structure in which the structure of the reflective film 2 was different in Example 1 shown in FIG. 3 was manufactured. In this comparative example, the reflective film 2 is provided only in the display region 3 with the structure shown in FIG. 3, the width dimension of the lead-out wiring 6 is set large, and the area ratio S2 / S1 is 0.0013. Is set.
Specific dimensions of each part are as follows.
[0081]
Dimensions of the reflective film 2 ″ corresponding to S1: 3.8 cm × 3.0 cm
The longest of the lead wires 6 that are a part of S2, that is, the width dimension of the lead wire 6a that is slanted like the one shown in FIG. 3 among the lead wires 6 located on the outermost side in the display region 3C. 155 μm x length 0.36 cm
Similar to the one shown in FIG. 3, the width dimension 70 μ × length 1.1 cm in the lead-out wiring 6 b extending in the left-right direction
Terminal part 5 width 50 μm × 0.3 cm
[0082]
Four thousand cells having the structures of Examples 1 to 3 and Comparative Example as described above were manufactured, and the defect rate at this time was measured.
The defect rate was expressed as a percentage of (number of cells in which even one display defect due to electrostatic discharge occurred) / (total number of manufactured cells).
The result is shown in FIG.
[0083]
According to this graph, in the comparative example in which the value of S1 / S2 is about 0.0013, the defect rate is about 30%, but in Example 1 in which the value of S1 / S2 is set to 0.001. In the second embodiment, the defect rate is reduced to 3% and the value of S1 / S2 is set to 0.0001. In Example 2, the defect rate is reduced to 0.5% and the value of S1 / S2 is set to 0. It can be seen that the defect rate is 0% in the set example 3.
[0084]
Thereby, in this invention, it turns out that it becomes possible to suppress the electric potential difference between each electrode resulting from the static electricity generate | occur | produced at the time of manufacture etc., and generation | occurrence | production of discharge between electrodes can be prevented.
[0085]
【The invention's effect】
According to the substrate, the liquid crystal display device, and the electronic apparatus of the present invention, the area S2 of the portion that does not overlap the reflective film (conductive coating film) in any one of the electrodes (wirings) on the substrate is reduced. By setting the ratio S2 / S1 with respect to the area S1 to be 0.001 or less, 0.0001, or 0, it is possible to suppress a potential difference between the electrodes caused by static electricity generated during manufacturing or the like. Therefore, it is possible to prevent the occurrence of discharge between the electrodes, to prevent an increase in the defect rate, which is the ratio of the number of products having display defects due to electrostatic discharge to the total number of products, and to improve the yield. The effect that can be produced.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a first embodiment of a liquid crystal display device according to the present invention.
2 is a cross-sectional view showing a common substrate in the liquid crystal display device of FIG.
FIG. 3 is a plan view showing a common substrate of FIG. 2;
4 is an enlarged plan view of FIG. 3. FIG.
FIG. 5 is a plan view showing a common substrate in a second embodiment of the liquid crystal display device of the present invention.
FIG. 6 is a plan view showing a common substrate in a third embodiment of the liquid crystal display device according to the present invention.
FIG. 7 is a cross-sectional view showing a common substrate in another embodiment of the liquid crystal display device according to the present invention.
FIG. 8 is a graph showing a variation in power failure potential of each lot in an alignment film printing process.
FIG. 9 is a graph showing an area ratio (S1 / S2) and a defect rate (%) in an example of the present invention.
FIG. 10 is a plan view showing a fourth embodiment of the electronic apparatus according to the invention.
11 is an exploded perspective view showing the electronic device of FIG.
FIG. 12 is a plan view showing a conventional liquid crystal display device.
FIG. 13 is a cross-sectional view showing another embodiment of the liquid crystal display device according to the present invention.
[Explanation of symbols]
1 ... Lower substrate (substrate)
2, 2 '... Reflective film (conductive coating film)
3, 3A, 3B, 3C, 3D ... display area
4, 34 ... Display electrodes
5 ... Terminal part
6, 6 '... Lead-out wiring
7, 37 ... Electrode (wiring)
11 ... Overcoat film
12. Shape transfer film
21 ... Color filter layer
31 ... Upper substrate
35 ... Electrode
41. Overcoat film
42, 43 ... Alignment film
44 ... Sealing material
45 ... Liquid crystal layer
46 ... Segment substrate
47 ... Common substrate (base)
20 ... Electromagnetic shielding film (conductive coating layer)

Claims (9)

A conductive coating film made of a conductive material on a substrate made of an insulating material, and a plurality of wirings formed in a film shape with respect to the coating film via the insulating film, the conductive coating film The substrate according to claim 1, wherein a ratio S2 / S1 of these areas is set to 0.001 or less in the area S1 and the area S2 of the portion of the wiring that does not overlap the conductive coating film. 2. The substrate according to claim 1, wherein the ratio S2 / S1 is set to 0.0001 or less. 2. The substrate according to claim 1, wherein all the wirings overlap with the conductive coating film. Among the pair of substrates that are disposed to face each other with the liquid crystal layer interposed therebetween and that have at least a predetermined pattern of electrodes on the surface on the liquid crystal layer side, the first substrate is provided with a conductive reflective film that covers at least the display region. And
In the first substrate, the ratio S2 / S1 of these areas is set to 0.001 or less in the area S1 of the reflective film and the area S2 of the portion of the front electrode that does not overlap the reflective film. A liquid crystal display device. 5. The liquid crystal display device according to claim 4, wherein the ratio S2 / S1 is set to 0.0001 or less. The liquid crystal display device according to claim 4, wherein all of the electrodes overlap the reflective film. On a substrate made of an insulating material, an electromagnetic shielding film made of a conductive material, and a plurality of wirings formed in a film shape with respect to the electromagnetic shielding film via an insulating film,
In the area S1 of the electromagnetic shielding film and the area S2 of the portion of the wiring that does not overlap the electromagnetic shielding film, a ratio S2 / S1 of these areas is set to 0.001 or less. Electronics. 8. The electronic apparatus according to claim 7, wherein the ratio S2 / S1 is set to 0.0001 or less. The electronic device according to claim 7, wherein all of the wirings overlap with the electromagnetic shielding film.

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