JP2006235333A - Display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device with improved humidity-resistance reliability. <P>SOLUTION: The display device has a liquid crystal panel 100 having a TFT array substrate 101 where a terminal portion is formed and a driving IC 105 mounted on a terminal formed at the terminal portion, and is equipped with a moisture-proof layer 107 covering a connection portion between the terminal and driving IC 105. The moisture-proof layer 107 contains a desiccating material. The liquid crystal panel 100 is equipped with a counter substrate 102 which is arranged opposite to the TFT array substrate 101 and stuck on the TFT array substrate 101 with a sealing material 103, and a gap formed between the TFT array substrate 101 and counter substrate 102 and outside the sealing material 103 is filled with the moisture-proof layer 107. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a display device, and more particularly to a display device in which an electronic component is mounted on a substrate.

  Currently, display devices are widely used as an interface for connecting people and machines, and have made remarkable progress. Liquid crystal display devices (LCDs) are widely applied as display devices for PCs and portable terminal devices because they have advantages such as low power consumption, thinness, and light weight.

  In recent years, in such a liquid crystal display device, the drive IC is directly mounted on the substrate of the liquid crystal panel from the viewpoint of reducing the number of members and man-hours required for manufacturing the drive IC package, reducing the fine pitch, and reducing the weight and thickness. A so-called COG (Chip On Glass) system to be mounted is adopted.

  The liquid crystal panel 10 used in such a liquid crystal display device has a configuration as shown in FIGS. 4 and 5, for example. A plurality of gate lines and a plurality of source lines formed in a lattice shape, pixel electrodes arranged in a matrix, and TFTs (Thin Film Transistors) that are switching elements connected to the source lines and the pixel electrodes were formed. The TFT array substrate 11 and the counter substrate 12 on which the common electrode is formed are arranged to face each other. The periphery of both the substrates is bonded by a frame-shaped sealing material 13, and liquid crystal (not shown) is sealed in a space formed by the TFT array substrate 11, the counter substrate 12, and the sealing material 13.

  Of the two substrates, one TFT array substrate 11 is formed to have a larger planar dimension than the other counter substrate 12, and a plurality of the gate lines described above are formed on the terminal portion of the TFT array substrate 11 formed larger. In addition, a source line terminal (not shown) is formed.

  On the terminal portion, a driving IC 15 is thermocompression bonded via an anisotropic conductive film (hereinafter referred to as ACF) 14 in which conductive particles are mixed in an adhesive. In addition, a flexible printed circuit (hereinafter referred to as FPC) 16 is connected to the terminal portion, and an LCD controller (not shown) or the like is connected thereto. By applying a driving voltage to the above-described pixel electrode by the driving IC 15, it is possible to change the alignment of the liquid crystal and perform a predetermined display.

  Conventionally, in the connection portion between the drive IC 15 and the FPC 16 and the terminal portion, there has been a problem that the terminal is corroded due to adhesion of moisture entering from the outside to the terminal portion. There was concern that it would adversely affect the display quality.

Therefore, conventionally, in order to prevent such disconnection due to corrosion of the terminals, a resin layer 17 made of silicone resin or the like is provided after the completion of the liquid crystal panel 10 so as to cover the connection portion between the drive IC 15 and the FPC 16 and the terminals. ing. (For example, refer to Patent Document 1.)
JP 2005-043810 A

  In recent years, with the further finer pitch of the wiring pattern, the pitch of the terminal is also narrowed, and the problem of such corrosion / electric corrosion becomes more serious. However, even with the resin layer 17 described above, adhesion of moisture or the like to the connection portion with the terminal portion cannot be completely prevented, and the problem of corrosion / electric corrosion cannot be solved.

  The cause of such a problem is that moisture permeates through the resin layer and penetrates into the interface between the ACF 14 coated with the resin layer 17 and the terminal portion. In particular, the intrusion of moisture into such a connecting portion becomes conspicuous under high temperature and high humidity, and has been a problem that cannot be ignored from the viewpoint of improving the reliability of the display device in such an environment.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a display device with improved moisture resistance reliability.

  A display device according to a first aspect of the present invention includes a display element having a first substrate provided with a terminal portion, an electronic component connected to the terminal formed in the terminal portion, the terminal, and the electronic device. A first resin layer covering a connecting portion with the component, wherein the first resin layer contains a water catching material. By adopting such a configuration, moisture resistance reliability can be improved.

  A display device according to a second aspect of the present invention is the display device according to the second aspect, wherein the display element is disposed opposite to the first substrate and is attached to the first substrate with a sealing material. The gap formed between the first substrate and the second substrate and formed on the outside of the sealing material is filled with the first resin layer. By having such a configuration, it is possible to suppress the intrusion of moisture into the inside between the two substrates sealed by the sealing material, and it is possible to suppress display quality deterioration.

  In the display device according to a third aspect of the present invention, in the above display device, the first substrate includes a wiring formed on the terminal portion and connected to the terminal, and the wiring includes the first wiring. It is covered with a resin layer. Thereby, the deterioration of the wiring can be prevented.

  A display device according to a fourth aspect of the present invention is the above display device, wherein the terminal electronic component is ACF-connected. The present invention is particularly effective in such a case.

  In the display device according to a fifth aspect of the present invention, in the above display device, the first resin layer has a content of the water capturing material of 1 to 10 wt%. Thereby, it can be manufactured easily.

  A display device according to a sixth aspect of the present invention is the above display device, wherein a second resin layer is provided on the first resin layer. By adopting such a configuration, moisture resistance reliability can be further improved.

  The display device according to a seventh aspect of the present invention is the display device according to the sixth aspect, wherein the first resin layer has a content of the water catching material of 50 wt% or less. As a result, the moisture resistance reliability can be further improved.

  The display device according to an eighth aspect of the present invention is the display device as described above, wherein the first resin layer is a moisture curable resin. As a result, the manufacturing process can be simplified.

  The display device according to a ninth aspect of the present invention is the display device as described above, wherein the first resin layer is a solvent-volatile resin. Accordingly, moisture is not generated when the resin layer is cured, and the moisture resistance reliability can be improved.

  An object of the present invention is to provide a display device with improved moisture resistance reliability.

  Hereinafter, embodiments to which the present invention can be applied will be described. The following description explains the embodiment of the present invention, and the present invention is not limited to the following embodiment. For clarity of explanation, the following description and drawings are omitted and simplified as appropriate. Further, those skilled in the art can easily change, add, and convert each element of the following embodiments within the scope of the present invention. In addition, in each drawing, the same code | symbol is attached | subjected to the same element and the overlapping description is abbreviate | omitted as needed for clarification of description.

Embodiment 1 FIG.
The configuration of the liquid crystal panel used in the liquid crystal display device according to Embodiment 1 of the present invention will be described with reference to FIGS. FIG. 1 is a front view showing the configuration of the liquid crystal panel according to the present embodiment. FIG. 2 is a side view showing a configuration in the vicinity of the terminal portion of the liquid crystal panel 100 shown in FIG. In this embodiment, an example using a TN (Twisted Nematic) type active matrix liquid crystal panel will be described. For the sake of explanation, the illustration of the moisture-proof layer 107 is omitted in FIG.

  1 and 2, a liquid crystal panel 100 includes a TFT array substrate 101, a counter substrate 102, a sealing material 103, an anisotropic conductive film (hereinafter referred to as ACF) 104, a driving IC 105, a flexible substrate (Flexible). Printed Circuit: hereinafter referred to as FPC) 106 and a moisture-proof layer 107. In the present invention, a point to be noted is the moisture-proof layer 107, which will be described in detail later.

  First, the overall configuration of the liquid crystal panel 100 will be described. The following description shows the configuration of a general TN type active matrix liquid crystal panel 100, and the present invention is not limited to the liquid crystal panel having the following configuration. The liquid crystal panel 100 has a configuration in which a liquid crystal (not shown) is sandwiched between a counter substrate 102 disposed opposite to a TFT (Thin Film Transistor) array substrate 101. On the TFT array substrate 101, gate lines (scanning lines) are formed in the horizontal direction and source lines (signal lines) are formed in the vertical direction, and TFTs are provided near the intersections of the gate lines and the source lines. In addition, a plurality of pixel electrodes are formed in a matrix between the gate line and the source line. The gate of the TFT is connected to the gate line, the source is connected to the source line, and the drain is connected to the pixel electrode.

  On the other hand, a common electrode, R (red), G (green) and B (blue) color filters and a BM (Black Matrix) are formed on the counter substrate. The common electrode is actually a transparent electrode formed on the substantially entire surface of the counter substrate so as to face the pixel electrode. As the pair of substrates, a transparent rectangular insulating substrate made of glass or the like is used. Further, an alignment film (not shown) oriented in a predetermined direction is provided on the opposing surfaces of the TFT array substrate 101 and the counter substrate 102. The TFT array substrate 101 and the counter substrate 102 are maintained at a predetermined interval by bead spacers or columnar spacers.

  The TFT array substrate 101 is formed to have a larger planar dimension than the counter substrate 102. Accordingly, a part of the TFT array substrate 101 is disposed so as to protrude from the counter substrate 102. The periphery of both the substrates is bonded by a frame-shaped sealing material 103, and liquid crystal (not shown) is sealed in a space formed by the TFT array substrate 101, the counter substrate 102, and the sealing material 103. The liquid crystal sandwiched between these two substrates is aligned in a predetermined direction by alignment films provided on the TFT array substrate 101 and the counter substrate 102.

  A polarizing plate (not shown) is attached to each of the outer surface of the TFT array substrate 101 and the outer surface of the counter substrate 102. For example, in a TN liquid crystal panel 100 that is a typical example of the liquid crystal panel 100, the polarizing plates on the non-viewing side and the viewing side are arranged so that their transmission axes are vertical or parallel.

  In the terminal portion where the TFT array substrate 101 protrudes from the counter substrate 102, the above-described lead lines for the gate lines and source lines are formed, and a terminal portion (not shown) is formed in a part of the lead lines. A driving IC 105 is connected to the terminal portion of the TFT array substrate 101 via the ACF 104. Each of the driving ICs 105 is a gate driver or a source driver, but is collectively referred to as a driving IC 105 here. The drive IC 105 is directly connected to the TFT array substrate 101 in the COG (Chip On Glass) method, but may be connected to the TFT array substrate 101 by TAB (Tape Automated Bonding).

  The FPC 106 is connected to the other terminal portion of the TFT array substrate 101 via the ACF 104. The FPC 106 is provided with terminal portions at both ends, one terminal portion is connected to the TFT array substrate 101, and the other terminal portion is connected to an external LCD controller or the like. The driving IC 105 generates a gate signal and a source signal from various control signals and display signals input from an external LCD controller via the FPC 106.

  A moisture-proof layer 107 is provided at the connection portion of the terminal portion of the TFT array substrate 101 to the driving IC 105 and the FPC 106 by the ACF 104 so as to cover the whole. Further, the moisture-proof layer 107 is provided so as to cover all the lead wirings formed in the terminal portion of the TFT array substrate 101. That is, the terminal portion of the TFT array substrate 101 and the electronic components disposed thereon are all covered with the moisture-proof layer 107.

  As shown in FIG. 2, the FPC 106 protrudes outward from the TFT array substrate 101, and a moisture-proof layer 107 is provided on a connection portion between the FPC 106 and the terminal portion of the TFT array substrate 101 on the back side of the FPC 106. A gap formed between the TFT array substrate 101 and the counter substrate 102 and formed outside the sealing material 103 is also covered with a moisture-proof layer 107. Further, a moisture-proof layer 107 is formed from the end surface of the TFT array substrate 101 to the back surface of the FPC 106. The moisture-proof layer 107 will be described in detail later.

  A backlight unit (not shown), which is a planar light source device, is provided on the back side of the TFT array substrate 101. As the backlight unit, a general unit including a light source such as a fluorescent tube or an LED and a light guide plate that guides light from the light source in a planar shape, a diffusion sheet, a prism sheet, and the like can be used.

  A gate signal is supplied from the driving IC 105 to each gate line, and all TFTs connected to one gate line selected by each gate signal are turned on simultaneously. Then, a gradation voltage corresponding to the display signal is supplied to each source line via the TFT in the on state, and charges are accumulated in the pixel electrode.

  The arrangement of the liquid crystal between the pixel electrode and the common electrode changes according to the potential difference between the pixel electrode where the charge is accumulated and the common electrode. The direction of polarization of the linearly polarized light that has passed through the non-viewing-side polarizing plate is controlled by the liquid crystal, and the transmittance of light transmitted through the viewing-side polarizing plate is controlled. Each pixel of the liquid crystal panel 100 displays various shades according to the shade of color corresponding to the amount of light transmitted and any one of RGB color displays. In the case of monochrome display, a color filter may not be provided.

  As the liquid crystal panel 100, in addition to the above active matrix type, a simple matrix type that does not have a switching element is known. Other types of liquid crystal panels include TN (Twisted Nematic) type liquid crystal panels, STN (Super Twisted Nematic) type liquid crystal panels, and IPS (In Plane Switching) type in which pixel electrodes and common electrodes are formed on the same substrate. Liquid crystal panels are known. The present invention is applicable to various types of liquid crystal panels as described above.

  Here, the moisture-proof layer 107 will be described in detail. The moisture-proof layer 107 is made of a resin material mixed with a water capturing material at a predetermined ratio. As the resin material, conventionally known moisture curable resins, solvent volatile resins, ultraviolet curable resins, thermosetting resins, and the like can be used. Moreover, various materials such as a physical adsorption type and a chemical adsorption type, such as zeolite and calcium oxide, can be used as the water capturing material. Thus, since the moisture-proof layer 107 is formed using the resin material containing the water catching material, moisture entering from the outside can be effectively captured by the water catching material, and the moisture resistance reliability is improved. be able to.

  Among the resin materials described above, it is preferable to use a moisture curable resin or a solvent volatile resin. Since these do not require a curing treatment after the disposition, they can prevent an increase in manufacturing steps. Further, it is more preferable to use a solvent volatile resin. The solvent-volatile resin is one that cures when the solvent volatilizes. Therefore, there is no curing reaction, and no moisture is generated along with this, so that the moisture-proof effect is high.

  The ratio of the water catching material is preferably 1 to 10% by weight of the resin material. By setting it as such a range, it can be set as the viscosity which is easy to apply | coat. Further, the gap between the TFT array substrate 101 and the counter substrate 102 is easily filled. Conventionally, an epoxy-based thermosetting resin used as the sealing material 103 has water permeability to some extent. For this reason, the sealing material 103 absorbs moisture in a high-humidity environment, and the absorbed moisture may enter the liquid crystal inside the sealing material 103, resulting in a display defect. . However, since the moisture-proof layer 107 is easily provided in the gap between the TFT array substrate 101 and the counter substrate 102 as described above, the occurrence of display defects can be suppressed.

  Moreover, the fall of the adhesiveness of the moisture-proof layer 107 can be suppressed by setting it as the above ratios. Therefore, electrical connection reliability and mechanical connection reliability of the connection portion between the terminal portion of the TFT array substrate 101 and the FPC 106 can be ensured.

Embodiment 2. FIG.
The configuration of the liquid crystal panel used in the liquid crystal display device according to the second embodiment of the present invention will be described with reference to FIG. FIG. 3 is a side view showing the configuration of the liquid crystal panel according to the present embodiment. 3, the same components as those in FIGS. 1 and 2 are denoted by the same reference numerals, and the description thereof is omitted. The present embodiment is different from the first embodiment in that a protective layer 108 is provided on the moisture-proof layer 107.

  As described above, the liquid crystal panel 100 used in the liquid crystal display device according to the second embodiment includes the TFT array substrate 101, the counter substrate 102, the sealing material 103, the ACF 104, the driving IC 105, the FPC 106, and the moisture-proof layer 107. . A protective layer 108 is provided on the moisture-proof layer 107. That is, the ACF 104 connecting portion between the terminal portion of the TFT array substrate 101 and the driving IC 105 and the FPC 106, the routing wiring formed in the terminal portion, the gap between the TFT array substrate 101 and the counter substrate 102, and the like. It is covered with two layers. As described above, the moisture resistance reliability can be further improved by arranging the moisture-proof layer 107 and the protective layer 108 with enhanced moisture absorption in a double manner.

  As the protective layer 108, conventionally used resin materials such as a moisture curable resin, a solvent volatile resin, an ultraviolet curable resin, and a thermosetting resin can be used. For the protective layer 108, a resin material that does not contain a water capturing material is used. Further, as described above, it is preferable to use a moisture curable resin or a solvent volatile resin. Since these do not require a curing treatment after the disposition, they can prevent an increase in manufacturing steps. Further, it is more preferable to use a solvent volatile resin. The solvent-volatile resin is one that cures when the solvent volatilizes. Therefore, there is no curing reaction, and no moisture is generated along with this, so that the moisture-proof effect is high.

  In the present embodiment, the protective layer 108 can ensure electrical connection reliability and mechanical connection reliability of the connection portion between the terminal portion of the TFT array substrate 101 and the FPC 106. For this reason, the moisture-proof layer 107 is not required to have high adhesion. Therefore, it is possible to add a water catching material to the moisture-proof layer 107. The ratio of the water catching material can be 50 wt% or less of the resin material. In this way, since a large amount of water catching material can be added, the moisture resistance reliability can be further improved. In addition, since only the water that has permeated the protective layer 108 is captured by the water capturing material, it is possible to further improve the moisture resistance reliability.

  In the above description, the case where the present invention is applied to a liquid crystal display device has been described. However, the present invention is not limited to this. For example, the present invention can be applied not to the liquid crystal panel 100 but to other display panels such as an organic EL panel and an inorganic EL panel. Furthermore, the components attached to the display panel 100 are not limited to the drive IC 105 and the FPC 106, but may be other electronic components. For example, sensors such as a temperature sensor, an optical sensor, and a humidity sensor can be attached as the electronic component. Of course, the electronic component to be attached is not limited to sensors, and may be an electronic circuit or a light source.

It is a front view which shows the structure of the liquid crystal panel used for the liquid crystal display device concerning Embodiment 1 of this invention. It is a side view which shows the structure of the edge part vicinity of the liquid crystal panel used for the liquid crystal display device concerning Embodiment 1 of this invention. It is a side view which shows the structure of the liquid crystal panel used for the liquid crystal display device concerning Embodiment 2 of this invention. It is a front view which shows the structure of the liquid crystal panel used for the conventional liquid crystal display device. It is a side view which shows the structure of the edge part vicinity of the liquid crystal panel used for the conventional liquid crystal display device.

Explanation of symbols

100 Liquid crystal panel 101 TFT array substrate 102 Counter substrate 103 Sealing material 104 ACF
105 Driving IC
106 FPC
107 Moisture-proof layer 108 Protective layer

Claims (9)

A display element having a first substrate provided with a terminal portion;
An electronic component connected to a terminal formed in the terminal portion;
A first resin layer covering a connection portion between the terminal and the electronic component;
The display device in which the first resin layer contains a water capturing material. The display element includes a second substrate disposed opposite to the first substrate and attached to the first substrate by a sealing material,
The display device according to claim 1, wherein a gap formed between the first substrate and the second substrate and formed outside the sealing material is filled with the first resin layer. The first substrate includes a wiring formed on the terminal portion and connected to the terminal,
The display device according to claim 1, wherein the wiring is covered with the first resin layer.   The display device according to claim 1, wherein the terminal and the electronic component are ACF-connected.   The display device according to claim 1, wherein the first resin layer has a content of the water capturing material of 1 to 10 wt%.   The display device according to claim 1, wherein a second resin layer is provided on the first resin layer.   The display device according to claim 6, wherein the first resin layer has a content of the water capturing material of 50 wt% or less.   The display device according to claim 1, wherein the first resin layer is a moisture curable resin.   The display device according to claim 1, wherein the first resin layer is a solvent-volatile resin.

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