JP2008176191A - Liquid crystal display and method for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display which can be made light, flat and low-cost, and by which customized products according to various purposes can be manufactured, and to provide a method for manufacturing the device. <P>SOLUTION: A touch panel 3 composrises a touch panel lower part electrode characteristic film 9 and a touch panel upper part electrode characteristic film 10. In a state with a CF substrate side polarizing plate 8 stuck to the CF substrate 7 of the liquid crystal 2, the touch panel lower part electrode characteristic film 9 as the substrate of the touch panel is stuck on the polarizing plate 8, and then the touch panel upper part electrode characteristic film 10 is stuck on the film 9. Thus, one sheet of a glass plate used for the conventional touch panel becomes unnecessary which contributes to a flat and lightweight liquid crystal display device. The touch panel can be manufactured as a step in the process of manufacturing the liquid crystal panel, which reduces the cost and can respond to customized products and avoids problems, such as deposition of dust, mixing of air bubbles and cracks in electrodes. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a liquid crystal display device and a manufacturing method thereof, and more particularly to a liquid crystal display device having a touch panel mounted on a liquid crystal panel and a manufacturing method thereof.

  Conventionally, liquid crystal display devices have been widely used as display devices due to advantages such as thinness, light weight, and low power consumption. This liquid crystal display device includes one substrate (hereinafter referred to as a TFT substrate) on which switching elements such as TFT (Thin Film Transistor) are formed in a matrix, a color filter (CF), a black matrix (BM), and the like. A liquid crystal panel in which liquid crystal is sandwiched between the other formed substrate (hereinafter referred to as a CF substrate) is provided, and the alignment direction of liquid crystal molecules is controlled by an electric field generated between electrodes provided on one or both substrates. By doing so, the light transmittance is changed.

  As an input device, there is a touch panel that detects a position touched by a finger or a touch pen touch, sends a signal, and performs an input operation based on the signal. This touch panel is configured by disposing an electric characteristic film on a glass substrate on which an electric characteristic pattern is formed, and is usually mounted and used on a liquid crystal panel.

  For example, as shown in FIG. 3, in a liquid crystal display device 11 in which a touch panel is mounted on a liquid crystal panel, a liquid crystal 16 is sandwiched between a TFT substrate 15 and a CF substrate 17, and outside the TFT substrate 15 and the CF substrate 17. A touch panel 13 including a liquid crystal panel 12 configured by disposing a TFT substrate side polarizing plate 14 and a CF substrate side polarizing plate 18, a touch panel glass 19 formed with an electrical characteristic pattern, and a touch panel electrical characteristic film 20. The touch panel 13 is arranged on the viewing surface side of the liquid crystal panel 12 (outside the CF substrate side polarizing plate 18) (see, for example, Patent Document 1 below).

  The manufacturing method of the liquid crystal display device is as shown in FIG. 4, and the liquid crystal panel 12 is manufactured through steps S201 to S204. In steps S205 to S206, an FPC (Flexible Printed Circuit for driver IC or liquid crystal panel) is manufactured. In step S207, a backlight is assembled on the back side of the liquid crystal panel 12, and in step S208, the touch panel 13 manufactured in advance by the touch panel manufacturer is assembled on the display surface side of the liquid crystal panel 12. Through steps S209 and S210, the liquid crystal display device 11 is completed.

JP 2004-348686 A

  Here, liquid crystal display devices equipped with a touch panel on a liquid crystal panel have a large demand for portable types, so that weight reduction, thinning and price reduction are required. Production is required.

  However, since the conventional touch panel is manufactured using a glass substrate, there is a problem that it is difficult to reduce the weight and thickness. Conventionally, after the backlight is assembled to the liquid crystal panel, a pre-manufactured touch panel is assembled, and the liquid crystal panel and the touch panel are manufactured in separate locations. In addition, there is a problem that it is difficult to reduce the price because work such as delivery time management is required.

  In addition, the LCD panel manufacturer and the touch panel manufacturer are different, so liquid crystal panels of various shapes and structures cannot be combined with touch panels, and custom products that meet various applications cannot be manufactured. There was also a problem.

  Against this background, there is a need for a process for manufacturing custom products that are lightweight and meet customer needs. Furthermore, a new structure and manufacturing method are required to cope with the current situation where it is difficult to procure materials in a short delivery time because a combination of various types of liquid crystal panels and various types of touch panels is required. .

  The present invention has been made in view of the above-mentioned problems, and its main purpose is to realize a liquid crystal display capable of realizing weight reduction, thickness reduction and price reduction, and manufacturing custom products corresponding to various uses. It is to provide an apparatus and a manufacturing method thereof.

  In order to achieve the above object, the present invention provides a liquid crystal display device in which a touch panel is mounted on a liquid crystal panel, and the touch panel is disposed on the liquid crystal panel side, and is in the form of a film or sheet in which a lower electrode is formed. The first member and a second member on which an upper electrode facing the lower electrode is formed, and the first member is directly attached to the liquid crystal panel.

  The method of the present invention is a method for manufacturing a liquid crystal display device in which a touch panel is mounted on a liquid crystal panel, wherein the liquid crystal is sandwiched between a pair of substrates, and polarizing plates are attached to both outer sides of the pair of substrates. A first step of manufacturing a liquid crystal panel; a second step of attaching a film-like or sheet-like first member having a lower electrode formed on the polarizing plate on the display surface side of the liquid crystal panel; A second member on which an upper electrode facing the lower electrode is attached on the first member, and the touch panel is formed by the first member and the second member. It has at least a process and a fourth process for assembling a backlight on the back side of the liquid crystal panel in this order.

  In this invention, it can be set as the structure which has the process of affixing FPC for touchscreens for driving the said touch panel to the said 1st member after the said 2nd process and before the said 3rd process. .

  Moreover, in this invention, it can be set as the structure which uses the said 1st member in which FPC for touch panels for driving the said touch panel was previously affixed in the said 2nd process.

  Moreover, in this invention, it can also be set as the structure which uses the said 2nd member in which FPC for touch panels for driving the said touch panel was previously affixed in the said 3rd process.

  In this way, the touch panel is composed of a film- or sheet-shaped first member on which the lower electrode is formed and a second member on which the upper electrode is formed. The first member and the second member are pasted on the plate in order, and a liquid crystal display device with a touch panel mounted on the liquid crystal panel is manufactured in a consistent process, realizing weight reduction, thickness reduction, and price reduction. In addition, it is possible to manufacture custom products according to various applications.

  According to the liquid crystal display device and the method of manufacturing the same of the present invention, the following effects can be obtained.

  The first effect of the present invention is that a liquid crystal display device having a touch panel mounted on a liquid crystal panel can be reduced in thickness and weight. The reason is that the glass plate used for the conventional touch panel can be reduced by one by configuring the touch panel with the touch panel lower electrode characteristic film and the touch panel upper electrode characteristic film.

  The second effect of the present invention is that it is possible to reduce the price of a liquid crystal display device in which a touch panel is mounted on a liquid crystal panel. The reason is that the touch panel lower electrode characteristic film is pasted immediately after the polarizing plate is pasted, and then the touch panel upper electrode characteristic film is pasted. .

  The third effect of the present invention is that custom products can be manufactured according to various uses. This is because the touch panel in the component state is assembled on the liquid crystal panel, so that various types of liquid crystal panels and various types of touch panels can be combined.

  As shown in the prior art, a liquid crystal display device in which a touch panel is mounted on a liquid crystal panel is used for a portable terminal such as a mobile phone, but the conventional liquid crystal display device has a backlight assembled on the liquid crystal panel. Later, it is a structure to assemble a finished touch panel, and it is difficult to reduce the weight and thickness because a glass substrate is used for the touch panel, and it is also necessary to store parts and manage delivery date, so it is low in price. In addition, there is a problem in that liquid crystal panels having various shapes and structures cannot be combined with touch panels, and custom products corresponding to various applications cannot be manufactured.

  Since such problems are caused by the fact that the liquid crystal panel and the touch panel are manufactured separately, in the present invention, the touch panel in the component state is assembled on the liquid crystal panel, and the liquid crystal panel and the touch panel are assembled on the liquid crystal panel in a consistent process. Manufactures liquid crystal display devices with touch panels. Specifically, with the polarizing plate attached to the CF substrate of the liquid crystal panel, the touch panel lower electrode characteristic film is applied as the touch panel substrate, and then the touch panel upper electrode characteristic film is applied. use.

  This eliminates the need for a single glass plate that has been used in conventional touch panels, and allows the liquid crystal display device to be made thinner and lighter. At the same time, the touch panel can be replaced with a liquid crystal display device without purchasing a finished touch panel. Therefore, it is possible to achieve a reduction in price.

  Moreover, in this invention, since the combination of the kind of liquid crystal panel, the kind of polarizing plate, the kind of touch-panel lower electrode characteristic film, and the kind of touch-panel upper electrode characteristic film is easy, it can respond to a custom product.

  In addition, since the touch panel lower electrode characteristic film is pasted directly on the CF substrate-side polarizing plate, the touch panel upper electrode characteristic film is overlapped to reduce the dust that has adhered to the liquid crystal panel and the touch panel. can do.

  Furthermore, in the conventional method of attaching the CF substrate side polarizing plate of the liquid crystal panel to the finished touch panel, there is a problem that it is difficult to apply a strong pressure evenly across the entire surface. Since the touch panel lower electrode characteristic film is laminated on top of each other, it is possible to apply a strong pressure evenly across the entire surface, which may cause bubbles between the liquid crystal panel and the touch panel, It is also possible to avoid problems such as the occurrence of cracks in ITO (Indium Tin Oxide) that constitutes.

  In order to describe the above-described embodiment of the present invention in more detail, a liquid crystal display device according to an embodiment of the present invention and a manufacturing method thereof will be described with reference to FIGS. FIG. 1 is a cross-sectional view schematically showing the configuration of the liquid crystal display device according to this embodiment, and FIG. 2 is a flowchart showing the method for manufacturing the liquid crystal display device of this embodiment.

  As shown in FIG. 1, in the liquid crystal display device 1 of this embodiment, the liquid crystal 6 is sandwiched between one substrate (for example, the TFT substrate 5) and the other substrate (for example, the CF substrate 7). 5 and a liquid crystal panel 2 each including at least a TFT substrate-side polarizing plate 4 and a CF substrate-side polarizing plate 8 on the outside of the CF substrate 7 and a back surface disposed on the back surface or side surface of the liquid crystal panel 2 to illuminate the liquid crystal panel Light (not shown), sheet-like or film-like touch panel lower electrode characteristic film 9 in which the lower electrode is patterned in the X or Y direction, and the upper electrode facing the lower electrode are patterned in the X or Y direction The touch panel 3 composed of the touch panel upper electrode characteristic film 10 is provided.

  That is, the lower electrode of the touch panel is not formed on the glass substrate as in the prior art, but is formed on the touch panel lower electrode characteristic film 9, and the touch panel lower electrode characteristic film 9 is polarized on the CF substrate side polarization. It is characterized by being placed in close contact with the plate 8.

  The present invention is characterized by the structure of the touch panel 3 and the method of forming the touch panel 3 on the liquid crystal panel 2, and the structure of the liquid crystal panel 2 (for example, the type of switching element, the inverted stagger type (bottom gate type) ) And positive stagger type (top-cate type) TFT structures and driving methods (IPS (In Plane Switching) method, TN (Twisted Nematic) method, etc.) are arbitrary, and the touch panel 3 method (for example, resistance) The electrode pattern shape of the touch panel lower electrode characteristic film 9 and the touch panel upper electrode characteristic film 10, the material of the electrode and the base material, etc. are not particularly limited.

  Hereinafter, the manufacturing procedure of the liquid crystal display device 1 having the above configuration will be described with reference to the flowchart of FIG.

  First, in step S101, the liquid crystal panel 2 is manufactured using a known method. For example, a TFT substrate 5 is manufactured by forming wiring elements (gate wiring and drain wiring) and switching elements such as TFTs that are substantially orthogonal to each other on a glass substrate, and a color filter or a black matrix is formed on the glass substrate. Thus, the CF substrate 7 is manufactured. Next, a polyimide solution as a material for the alignment film is applied to the surfaces of the TFT substrate 5 and the CF substrate 7 using a printing apparatus and baked, and then a buff cloth in which the alignment film surface is wound around a rotating metal roller. Then, rubbing treatment is performed by rubbing in a certain direction, and washing and drying are performed to remove rubbing treatment residues such as fiber waste of buff cloth and shavings of alignment film. Next, using a dispenser drawing method or the like, a sealing material for sealing the liquid crystal is drawn on one substrate and Ag is applied, and spacers such as polymer beads and silica beads are dispersed on the other substrate and fixed. Then, the liquid crystal is dropped onto the substrate on which the sealing material is drawn, the two substrates are bonded together, the sealing material is cured while being pressed to manufacture the liquid crystal panel 2, and then the liquid crystal panel 2 is washed.

  Next, in step S102, the TFT substrate side polarizing plate 4 is attached to the TFT substrate 5 side of the liquid crystal panel 2, and the CF substrate side polarizing plate 8 is attached to the CF substrate 7 side.

  Next, in step S <b> 103, the touch panel lower electrode characteristic film 9 is disposed on the CF substrate-side polarizing film 8, and a predetermined pressure is applied from above the touch panel lower electrode characteristic film 9 to be attached to the CF substrate-side polarizing film 8. . The material and structure of the film constituting the touch panel lower electrode characteristic film 9, the material of the electrode, the structure, and the pattern are not particularly limited, but the film and the electrode are members having high transmittance so as not to impair the visibility of the liquid crystal panel 2. For example, a polyester resin such as PET (polyethylene terephthalate), a polycarbonate resin, an epoxy resin, an acrylic resin, or the like can be used as the film, and ITO or the like can be used as the lower electrode.

  Here, conventionally, the touch panel glass 19 in which the lower electrode is formed on the glass substrate is used. However, in this embodiment, since the sheet-shaped or film-shaped touch panel lower electrode characteristic film 9 is used, the glass is used. A substrate is not required, and the liquid crystal display device can be reduced in thickness and weight.

  Conventionally, since the finished touch panel 13 is used, there is a problem that dust or the like is easily mixed between the CF substrate side polarizing plate 18 and the touch panel 13. In this embodiment, the CF substrate 7 is used. After the CF substrate side polarizing plate 8 is attached to the touch panel, the touch panel lower electrode characteristic film 9 is immediately attached, so that contamination of the dust can be prevented.

  In addition, since the finished touch panel 13 has been conventionally used, a uniform force cannot be applied from above the touch panel 13, and air bubbles may enter between the liquid crystal panel 12 and the touch panel 13, Although there was a problem that cracks occur in the ITO that is configured, in this embodiment, since a single touch panel lower electrode characteristic film 9 is applied, a uniform force is applied from above the touch panel lower electrode characteristic film 9. And the above problem can be avoided.

  Next, in step S104, a touch panel FPC for driving the touch panel 3 is attached to the touch panel lower electrode characteristic film 9 so that a signal detected by the touch panel 3 can be taken out. The structure and shape of the FPC for touch panel, the electrical connection method with the touch panel lower electrode characteristic film 9, the pasting method, and the like are not particularly limited. Further, the FPC for touch panel may use an integrated product that is attached to the touch panel upper electrode characteristic film 10 from the beginning, or may be an integrated product that is attached to the touch panel lower electrode characteristic film 9 from the beginning. In this case, the step of attaching the touch panel FPC can be omitted.

  Next, in step S105, a touch panel upper electrode characteristic film 10 in which an upper electrode pattern facing the lower electrode of the touch panel lower electrode characteristic film 9 is formed on the touch panel lower electrode characteristic film 9 with a predetermined gap therebetween. wear. The material and structure of the film constituting the touch panel upper electrode characteristic film 10, the material of the electrode, the structure, the pattern, the distance between the two films, etc. are not particularly limited. It is preferable to use a member having a high transmittance so as not to impair the visibility of the panel 2. For example, a polyester resin, a polycarbonate resin, an epoxy resin, an acrylic resin, or the like can be used as the film, and ITO or the like is used as the lower electrode. be able to.

  Next, after pressurizing and heating with an autoclave in step S106, an appearance inspection of the liquid crystal panel 2 is performed in step S107. Here, since the touch panel 13 has been assembled after the appearance inspection of the liquid crystal panel 12 heretofore, there was a risk of appearance defects due to the assembly of the touch panel 13 after the appearance inspection. There is no such worry.

  Next, in step S108, an IC chip such as a driver IC is mounted on the substrate of the liquid crystal panel 2 (usually the TFT substrate 5) by COG (Chip On Grass), and then in step S109, the liquid crystal panel 2 is driven. The FPC (Film On Grass) is mounted on the liquid crystal panel FPC, and a backlight is assembled on the back surface of the liquid crystal panel 2 in step S110.

  Here, conventionally, since the finished touch panel 13 has been assembled after assembling the backlight, it has been difficult to change the size and function. In this embodiment, however, the touch panel 3 is changed by the manufacturing process of the liquid crystal display device 1. Because it is assembled, it can easily accommodate custom products suitable for various applications.

  In addition, since the finished touch panel 13 is conventionally used, operations such as storage of members and delivery date management are necessary. However, in this embodiment, the touch panel 3 is assembled in the manufacturing process of the liquid crystal display device 1. It is possible to reduce assembly man-hours, shorten tact time, and reduce material storage.

  Thereafter, soldering is performed in step S111, module inspection is performed in step S112, and the liquid crystal display device 1 of this embodiment is completed in step S113.

  Thus, in this example, since the sheet-like or film-like touch panel lower electrode characteristic film 9 is used in place of the touch panel glass 19 on which the lower electrode pattern is formed, it is possible to realize a reduction in thickness and size. Further, in this embodiment, as a part of the manufacturing process of the liquid crystal display device, the touch panel lower electrode characteristic film 9 is directly pasted on the CF substrate-side polarizing plate 8 and then the touch panel upper electrode characteristic film 10 is pasted. The cost can be reduced by reducing man-hours, tact shortening, and the amount of material storage, and it is possible to easily cope with custom products suitable for various applications. Further, in this embodiment, the touch panel lower electrode characteristic film 9 is attached on the CF substrate side polarizing plate 8, and therefore, a uniform force is applied to the touch panel lower electrode characteristic film 9 to the CF substrate side polarizing film 8. They can be brought into close contact with each other, so that bubbles and cracks can be prevented, and dust can be prevented from being mixed.

  In addition, this invention is not limited to the said Example, Unless it deviates from the meaning of this invention, it can change suitably.

  INDUSTRIAL APPLICABILITY The present invention is not limited to a liquid crystal display device and a manufacturing method thereof, and is used for any display device in which a touch panel is mounted on a display panel, such as an organic EL display device in which a touch panel is mounted on an organic EL (electroluminescence) display panel. Is possible.

It is sectional drawing which shows typically the structure of the liquid crystal display device by which the touch panel was mounted on the liquid crystal panel which concerns on one Example of this invention. It is a flowchart figure which shows the manufacture procedure of the liquid crystal display device based on one Example of this invention. It is sectional drawing which shows typically the structure of the liquid crystal display device by which the touch panel was mounted on the conventional liquid crystal panel. It is a flowchart figure which shows the manufacture procedure of the conventional liquid crystal display device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Liquid crystal display device 2 Liquid crystal panel 3 Touch panel 4 TFT substrate side polarizing plate 5 TFT substrate 6 Liquid crystal 7 CF substrate 8 CF substrate side polarizing plate 9 Touch panel lower electrode characteristic film 10 Touch panel upper electrode characteristic film 11 Liquid crystal display device 12 Liquid crystal panel 13 Touch panel 14 TFT substrate side polarizing plate 15 TFT substrate 16 Liquid crystal 17 CF substrate 18 CF substrate side polarizing plate 19 Touch panel glass 20 Touch panel electrical property film

Claims (5)

In a liquid crystal display device in which a touch panel is mounted on a liquid crystal panel,
The touch panel includes a film- or sheet-shaped first member formed with a lower electrode and a second member formed with an upper electrode facing the lower electrode, which are disposed on the liquid crystal panel side. ,
The liquid crystal display device, wherein the first member is directly attached to the liquid crystal panel. A method of manufacturing a liquid crystal display device having a touch panel mounted on a liquid crystal panel,
A first step of manufacturing the liquid crystal panel by sandwiching a liquid crystal between a pair of substrates and attaching polarizing plates to both outer sides of the pair of substrates;
A second step of attaching a film-like or sheet-like first member having a lower electrode formed on the polarizing plate on the display surface side of the liquid crystal panel;
A second member on which an upper electrode facing the lower electrode is attached on the first member, and the touch panel is formed by the first member and the second member. Process,
A method of manufacturing a liquid crystal display device, comprising at least a fourth step of assembling a backlight on the back side of the liquid crystal panel in this order.   3. The liquid crystal according to claim 2, further comprising a step of attaching an FPC for a touch panel for driving the touch panel to the first member after the second step and before the third step. Manufacturing method of display device.   3. The liquid crystal display device according to claim 2, wherein in the second step, the first member to which an FPC for a touch panel for driving the touch panel is attached in advance is used.   3. The liquid crystal display device according to claim 2, wherein in the third step, the second member to which an FPC for a touch panel for driving the touch panel is attached in advance is used.

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