JP2010170126A - Method and apparatus for manufacturing liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for manufacturing a liquid crystal display device for shortening the tact time without causing any detection failure during panel examination. <P>SOLUTION: The method for manufacturing the liquid crystal display device includes: a stacking step of stacking polarizing sheets of the same or different configurations on the front and back surfaces of a liquid crystal cell in which a liquid crystal layer is interposed between a first substrate and a second substrate, thereby fabricating a liquid crystal display panel; and an examining step of optically examining the liquid crystal display panel. The stacking step includes: a first-polarizing sheet attaching step of attaching a first polarizing sheet to the first substrate where potential hardly lower after charged than the second substrate; and a second-polarizing sheet attaching step of attaching a second polarizing sheet to the second substrate where the potential lowers more easily after charged than the first substrate after the first-polarizing sheet attaching step. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a liquid crystal display device manufacturing method and a liquid crystal display device manufacturing device, and more specifically, a liquid crystal display device manufacturing method for manufacturing a liquid crystal display device by attaching a liquid crystal cell and an optical film, and a liquid crystal display device It relates to a manufacturing apparatus.

  The liquid crystal display device includes a liquid crystal display panel (liquid crystal display unit) configured by attaching polarizing plates (polarizing members) to both front and back surfaces of a liquid crystal cell in which a liquid crystal layer is sandwiched between a pair of glass substrates. It is. Conventionally, as a method of attaching a polarizing plate to a liquid crystal cell, for example, as described in Patent Literature 1 to Patent Literature 3 below, a liquid crystal cell and a polarizing plate are fed between a pair of attaching rollers, and polarized into the liquid crystal cell. A method of pasting a plate is known.

  By the way, after constructing a liquid crystal display panel by laminating polarizing plates on both sides of the liquid crystal cell as described above, an inspection for inspecting the presence or absence of defects in the bonded state or defects due to adhesion of dust or the like. A process (panel inspection process) may be performed. In this inspection, for example, reflected light when light is irradiated on the surface of the liquid crystal display panel and transmitted light when light is irradiated from the back surface of the liquid crystal display panel are captured as image data by a CCD camera or the like, and image analysis is performed. It is implemented by doing.

JP 2005-37416 A JP 2005-37418 A JP 2006-39238 A

  However, when the above-described panel inspection process is performed on a liquid crystal display panel manufactured by a conventional pasting process, the alignment state of the liquid crystal changes for some reason, which adversely affects reflected light and transmitted light. The panel inspection process cannot be performed accurately because it may lead to so-called false detections that may be judged as defective or defective even though such defects and defects do not actually exist. was there.

  In particular, when a liquid crystal display panel is manufactured at a high speed by continuously automatically attaching a polarizing plate to a liquid crystal cell as in Patent Document 1 and Patent Document 2, such a problem becomes more apparent. Become. If a false detection occurs in the panel inspection process, the liquid crystal display panel must be re-inspected or reworked (a process of attaching another polarizing plate after peeling off the polarizing plate), resulting in a decrease in yield or productivity. It can be a factor.

  As will be described later, the present inventors have found that if the interval between the polarizing plate attaching step and the panel inspection step is increased, the above-described problem of false detection can be solved, but the tact time is long. Thus, in the automatic sticking method of the polarizing plate as in Patent Document 1, the high-speed continuous manufacturability is greatly impaired.

  In addition, as described later, the present inventors have also found that the above-described erroneous detection problem can be solved by weakening the pressure applied by the application roller used for application of the polarizing plate. Decreasing the pressure applied by the roller may cause another problem that air bubbles are mixed between the liquid crystal cell and the polarizing plate.

  The present invention has been made in view of the above problems, and after a polarizing plate is attached to both the front and back surfaces of a liquid crystal cell to produce a liquid crystal display panel, the liquid crystal display panel is optically inspected. In such a case, it is possible to suppress the change in the alignment state of the liquid crystal at the time of attaching the polarizing plate, and to perform the subsequent inspection process without adversely affecting the change in the alignment state of the liquid crystal. An object of the present invention is to provide a method for manufacturing a liquid crystal display device and a manufacturing apparatus for a liquid crystal display device that can reduce the tact time without incurring any problems.

  As a result of intensive studies by the present inventors, it was found that the cause of the non-uniform orientation of the liquid crystal during the inspection was due to the charging of the liquid crystal cell in the polarizing plate attaching process (lamination process). did. Furthermore, as a result of further research, we can reduce the time interval between the stacking process and the inspection process because the charging of the liquid crystal cell can be suppressed by setting the bonding order of the polarizing plates to the substrate to a specific order. However, it is found that the subsequent inspection process can be carried out without adversely affecting the change in the alignment state of the liquid crystal, and as a result, the tact time can be shortened without causing erroneous detection in the panel inspection, and the present invention is completed. It came.

That is, the present invention provides a liquid crystal display panel by laminating polarizing plates having the same or different structures on both front and back surfaces of a liquid crystal cell provided with a liquid crystal layer between a first substrate and a second substrate; A method for manufacturing a liquid crystal display device comprising an inspection step for optically inspecting the liquid crystal display panel,
The first polarizing plate attaching step of attaching the first polarizing plate to the first substrate that is less likely to be attenuated after charging than the second substrate, and the first polarizing plate attaching step, There is provided a method of manufacturing a liquid crystal display device, comprising: a second polarizing plate pasting step of sticking a second polarizing plate to the second substrate that is more easily attenuated after charging than the substrate.

In the method for manufacturing a liquid crystal display device according to the present invention, preferably, in the first polarizing plate pasting step, a plurality of first polarizing plates cut at a predetermined interval are arranged along a longitudinal direction on the first strip carrier film. The first strip-shaped body continuously formed so as to be peelable is supplied, the first strip-shaped carrier film is folded back with a knife edge, and the first polarizing plate is sequentially peeled from the first strip-shaped carrier film, and the peeled first polarizing plate is A step of sticking to the first substrate of the liquid crystal cell to be sequentially supplied, or a first strip in which a first polarizing plate longer than the liquid crystal cell is formed to be peelable on the first strip carrier film, and a knife A liquid crystal cell in which the first strip-shaped carrier film is folded at the edge to partially peel the long first polarizing plate from the first strip-shaped carrier film, and the stripped long first polarizing plate is sequentially supplied. First of Was attached to the plate, a step of cutting the portion of the first long polarizing plate affixed in length corresponding to the liquid crystal cell,
The second polarizing plate pasting step supplies a second strip in which a plurality of second polarizing plates cut at predetermined intervals are continuously formed on the second strip carrier film so as to be peelable along the longitudinal direction. The second band-shaped carrier film is folded back at the edge, the second polarizing plate is sequentially peeled from the second band-shaped carrier film, and the peeled second polarizing plate is sequentially supplied to the liquid crystal cell to which the first polarizing plate is attached. A step of affixing to the second substrate, or a second polarizing plate having a longer length than the liquid crystal cell is supplied on the second band-shaped carrier film so as to be peelable, and the second band-shaped carrier film is formed with a knife edge. The long second polarizing plate was partially peeled off from the second belt-like carrier film, and the peeled long second polarizing plate portion was attached to the first polarizing plate that was sequentially supplied. On the second substrate of the liquid crystal cell After Attach a step of cutting the portion of the second long polarizing plate affixed in length corresponding to the liquid crystal cell,
The inspection step is a step of optically sequentially inspecting the liquid crystal display panel conveyed after the second polarizing plate attaching step.

  In the method for manufacturing a liquid crystal display device according to the present invention, preferably, in the first polarizing plate pasting step, the first polarizing plate and the liquid crystal cell are at least partially overlapped with each other. , Sandwiched between a first pressure member pressurized from the first polarizing plate side and a second pressure member pressurized from the liquid crystal cell side, and the first polarized light with respect to the first pressure member and the second pressure member It is performed by relatively moving the plate and the liquid crystal cell.

  In the method for manufacturing a liquid crystal display device according to the present invention, preferably, the second polarizing plate attaching step includes at least one of the liquid crystal cell to which the first polarizing plate is attached and the second polarizing plate. Between the third pressure member pressed from the second polarizing plate side and the fourth pressure member pressed from the first polarizing plate affixed to the liquid crystal cell, and The liquid crystal cell in which the first polarizing plate is laminated with respect to the three pressure members and the fourth pressure member and the second polarizing plate are moved relative to each other.

In the method for manufacturing a liquid crystal display device according to the present invention, preferably, the first substrate includes a plurality of gate wirings, and a plurality of sources provided orthogonally via the plurality of gate wirings and an insulating film. A circuit portion including a wiring, a plurality of switching elements provided at intersections of the plurality of gate wirings and the plurality of source wirings, and a plurality of pixel electrodes connected to the plurality of switching elements,
The second substrate has a common electrode provided to face the plurality of pixel electrodes,
The liquid crystal layer is driven by applying an electric field between the pixel electrode and the common electrode in a direction substantially perpendicular to the substrate surfaces of the first substrate and the second substrate. .

In the method of manufacturing a liquid crystal display device according to the present invention, preferably, the first substrate is a conductive member (preferably a conductive member having a surface resistance value of 1.0 × 10 ¹² Ω / □ or less). Without
The second substrate has a pixel electrode and a common electrode for driving the liquid crystal layer by applying an electric field in a direction substantially parallel to the substrate surface.

In the method for manufacturing a liquid crystal display device according to the present invention, preferably, the first polarizing plate is provided with a conductive layer having a surface resistance value of 1.0 × 10 ¹² Ω / □ or less. It is characterized by that.

Furthermore, the present invention provides a laminating means for laminating polarizing plates having the same or different configurations on both front and back surfaces of a liquid crystal cell provided with a liquid crystal layer between a first substrate and a second substrate, An apparatus for manufacturing a liquid crystal display device comprising an inspection means for optically inspecting the liquid crystal display panel,
The laminating means is disposed at a stage subsequent to the first polarizing plate attaching means, a first polarizing plate attaching means for attaching the first polarizing plate to the first substrate, which is less likely to attenuate the potential after charging than the second substrate, An apparatus for manufacturing a liquid crystal display device is provided, comprising: a second polarizing plate attaching means for attaching a second polarizing plate to the second substrate, which is more easily attenuated after charging than the first substrate.

Also, the present invention is preferably in the liquid crystal display manufacturing apparatus,
The first polarizing plate pasting means is configured to remove a first belt-shaped carrier film from a belt-like body in which a plurality of first polarizing plates cut at predetermined intervals are continuously formed on the first belt-like carrier film so as to be peelable along the longitudinal direction. A knife edge that is folded to sequentially peel the first polarizing plate from the first band-shaped carrier film, and a sticking means for sticking the peeled first polarizing plate to the first substrate of the liquid crystal cell that is sequentially supplied, Alternatively, the first band-shaped carrier film is folded from the first band-shaped body in which the first polarizing plate longer than the liquid crystal cell is formed to be peelable on the first band-shaped carrier film, and the first band-shaped carrier film has a long first length. A knife edge that partially peels one polarizing plate, a pasting means for sticking the peeled portion of the long first polarizing plate to the first substrate of the liquid crystal cell that is sequentially supplied, and a long first polarizing plate Part of The are those in which a cutting means for cutting a length corresponding to the liquid crystal cell,
The second polarizing plate affixing means includes a second belt-shaped carrier from a second belt-like body in which a plurality of second polarizing plates cut at predetermined intervals are continuously formed on the second belt-like carrier film so as to be peelable along the longitudinal direction. The second edge of the liquid crystal cell to which the first polarizing plate is attached, the knife edge for turning the film back and sequentially peeling the second polarizing plate from the second strip carrier film, and the peeled second polarizing plate are sequentially supplied. The second strip carrier film is folded from a strip provided with a pasting means for pasting on a substrate, or a strip in which a second polarizing plate longer than a liquid crystal cell is formed on the second strip carrier film. A liquid crystal cell to which the first polarizing plate is attached, wherein a knife edge for partially peeling the second polarizing plate from the second strip carrier film and a portion of the peeled long second polarizing plate are sequentially supplied. The first A sticking means to be pasted to the substrate, which part of the second long polarizing plate and a cutting means for cutting a length corresponding to the liquid crystal cell,
The inspection means is means for optically sequentially inspecting the liquid crystal display panel that has been transported after the second polarizing plate attaching means.

  In the liquid crystal display device manufacturing apparatus according to the present invention, preferably, the first polarizing plate pasting means includes the first polarizing plate and the liquid crystal cell at least partially overlapped with each other. A first pressure member on the first polarizing plate side to be sandwiched and a second pressure member on the liquid crystal cell side are provided, and the first polarizing plate and the liquid crystal cell are provided to the first pressure member and the second pressure member. The first polarizing plate can be attached to the first substrate by being relatively moved.

  In the manufacturing apparatus for a liquid crystal display device according to the present invention, preferably, the second polarizing plate attaching means includes at least one of the liquid crystal cell to which the first polarizing plate is attached and the second polarizing plate. A third pressure member on the second polarizing plate side and a fourth pressure member on the liquid crystal cell side to which the first polarizing plate is attached, sandwiched in a state where the parts are stacked on each other, and the third pressure member The second polarizing plate can be attached to the second substrate by relatively moving the liquid crystal cell in which the first polarizing plate is laminated with respect to the member and the fourth pressure member and the second polarizing plate. It is characterized by being.

  According to the method and apparatus for manufacturing a liquid crystal display device according to the present invention, in the case of manufacturing a liquid crystal display panel by attaching polarizing plates to both front and back surfaces of a liquid crystal cell, the liquid crystal in the polarizing plate attaching step (lamination step). Since the charging of the cell is suppressed, it is possible to carry out the subsequent inspection process without adversely affecting the charging of the liquid crystal cell even if the time interval between the lamination process and the inspection process is shortened. The tact time at the time of manufacturing the liquid crystal display device can be greatly shortened without causing erroneous detection in the inspection process. In particular, in a method in which a polarizing plate is continuously and automatically attached to a liquid crystal cell, a remarkable effect of assuring high-speed continuous manufacturability of the liquid crystal display panel is exhibited.

1 is a schematic cross-sectional view of a liquid crystal display panel manufactured in Embodiment 1. FIG. 3 is a flowchart showing an embodiment of a method for manufacturing a liquid crystal display device according to the first embodiment. 1 is a schematic configuration diagram illustrating a manufacturing apparatus for a liquid crystal display device according to Embodiment 1. FIG. The schematic block diagram which expanded and showed 1st polarizing plate original fabric preparation process S1 and 1st cutting process S2 in the said FIG. The schematic block diagram which expanded and showed 2nd polarizing plate original fabric preparation process S4 and 2nd cutting process S5 in the said FIG. The schematic block diagram which expanded and showed inspection process S7 in the said FIG. The cross-sectional schematic diagram which showed the structure of the film provided with the 1st polarizing plate between 1st polarizing plate original fabric preparation process S1 to 1st polarizing plate sticking process S3a. The cross-sectional schematic diagram which showed the structure of the film provided with the 1st polarizing plate between 2nd polarizing plate original fabric preparation process S4 to 2nd polarizing plate sticking process S3b. FIG. 4 is a schematic cross-sectional view of a liquid crystal display panel manufactured in Embodiment 2. The graph which showed the result of having measured the ease of electrification of a CF substrate and a TFT substrate.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

(Embodiment 1)
FIG. 1 is a schematic cross-sectional view of a liquid crystal display panel Y manufactured continuously at high speed in the first embodiment. As shown in FIG. 1, the liquid crystal display panel Y according to the present embodiment includes a liquid crystal cell 4 configured to sandwich a liquid crystal layer 43 located in the center between a pair of substrates 41 and 42, and a first liquid crystal cell 4. The first polarizing plate 10 is laminated on the substrate 41 side, and the second polarizing plate 20 is laminated on the second substrate 42 side of the liquid crystal cell 4. The liquid crystal cell 4 in this embodiment is of a vertical alignment type (vertical alignment, hereinafter referred to as “VA method”).

  A substrate 41 (hereinafter also referred to as a back side substrate) disposed on the back side of the liquid crystal cell 4, that is, on the backlight side, has a plurality of gate wirings and a plurality of gates on a transparent substrate 411 such as glass or plastic. A circuit portion having a plurality of source wirings provided orthogonally via wiring and an insulating film, and a thin film transistor as a plurality of switching elements provided at intersections of the plurality of gate wirings and the plurality of source wirings ( TFT) 412, an interlayer insulating film 413 provided on the switching element (thin film transistor), and the plurality of switching elements 412 provided on the interlayer insulating film 413 through contact holes formed in the interlayer insulating film 413. A plurality of transparent electrodes (pixel electrodes) 414 connected to each of them, and an arrangement provided on the transparent electrodes (pixel electrodes) 414 And it has a film 415.

  The thin film transistor 412 includes a gate electrode, a semiconductor layer facing the gate electrode with a gate insulating film interposed therebetween, and a source electrode and a drain electrode individually connected to the semiconductor layer. A gate wiring is connected to the gate electrode, a source wiring is connected to the source electrode, and a pixel electrode 414 is connected to the drain electrode.

  The gate wiring and the gate electrode, and the source wiring, the source electrode, and the drain electrode are formed by depositing a metal film such as titanium, chromium, aluminum, or molybdenum, an alloy film thereof, or a stacked film thereof using a sputtering method or the like. It is formed by a patterning method using an etching method or the like.

  The semiconductor layer is formed by a method of forming a semiconductor material such as amorphous silicon or polysilicon by a plasma CVD (Chemical Vapor Deposition) method or the like, and patterning by a photoetching method or the like.

  The pixel electrode 414 is formed by a method of forming a transparent conductive material such as indium tin oxide (ITO), indium zinc oxide, tin oxide, or zinc oxide by a sputtering method or the like and then patterning the film by a photoetching method or the like.

  The alignment film 415 is formed by a method of applying a rubbing process by applying a polyimide resin to form a film.

  On the other hand, a substrate 42 (hereinafter also referred to as a display surface side substrate) disposed on the image display surface side of the liquid crystal cell 4 of Embodiment 1 is provided with a color filter 422 and a color filter on a transparent substrate 421 such as glass or plastic. An overcoat layer (not shown) provided on the filter 422; a transparent electrode (common electrode) 424 provided on the overcoat layer and opposed to the plurality of pixel electrodes 414; and the transparent electrode (Common electrode) 424 provided on the alignment film 424.

  As the color filter 422, a filter comprising a black matrix that shields the gaps between the colored patterns and red, green, and blue colored layers corresponding to each pixel is preferably used.

The black matrix is usually made of metallic chromium and has a thickness of 100 to 150 nm.
Moreover, what colored the resin material with dye and a pigment is used for the said colored layer, and a film thickness shall be 1-3 micrometers normally. As the pixel pattern arrangement of the colored layer, a delta arrangement, a mosaic arrangement, a stripe arrangement, or the like is employed.
Moreover, the said overcoat layer consists of an acrylic resin, an epoxy resin, etc., and a film thickness is 0.5-2 micrometers normally.

  The manufacturing method of the color filter 422 is not particularly limited, and color filters manufactured by various conventionally known methods can be employed. Examples of the method for producing the color filter include a dyeing method, a pigment dispersion method, a printing method, and an electrodeposition method.

  The common electrode 424 is formed by a method in which a transparent conductive material such as indium tin oxide (ITO), indium zinc oxide, tin oxide, or zinc oxide is formed by sputtering or the like and then patterned by a photoetching method or the like.

  The liquid crystal layer 43 constituting the liquid crystal cell 4 is composed of, for example, nematic liquid crystal molecules 431 having negative dielectric anisotropy (Δε <0). The liquid crystal layer 43 is driven by applying a voltage in a direction substantially perpendicular to the substrate surface between the pixel electrode 414 on the back substrate 41 and the common electrode 424 on the display substrate 42. That is, when the voltage is less than the threshold voltage, as shown in FIG. 1, the major axis of the liquid crystal molecules is aligned substantially perpendicular to the substrate surface, and the incident linearly polarized light from the back side is the liquid crystal Since it does not receive the birefringence effect when passing through the layer 43, it cannot pass through the second polarizer 21 of the second polarizing plate 20 on the display surface side. On the other hand, when the voltage is equal to or higher than the threshold voltage, the long axis of the liquid crystal molecules 431 is inclined with respect to the substrate surface by a predetermined angle depending on the magnitude of the voltage, and therefore the incident linearly polarized light from the back side is liquid crystal When passing through the layer 43, it undergoes a birefringence effect and changes to elliptically polarized light, and part of the light passes through the second polarizer 21 of the second polarizing plate 20 on the display surface side.

  In the liquid crystal cell 4 according to the first embodiment, due to the substrate configuration as described above, the back-side substrate 41 is a substrate that is easily charged, that is, a substrate that is not easily attenuated after being charged. Yes. Therefore, when the VA mode liquid crystal cell as in the first embodiment is adopted, in the present invention, the back substrate 41 is the first substrate to which the polarizing plate is to be attached first, while the display surface substrate 42. Becomes the second substrate.

  The type of the liquid crystal cell 4 in the present invention is not particularly limited. In addition to the VA method described above, the back side substrate has a pixel electrode and the display surface side substrate has a common electrode, as in the VA method. A TN (Twisted Nematic) method, a Super-Tistated Nematic (STN) method, and an OCB (Optically Compensated Birefringence) for driving the liquid crystal layer by applying an electric field between the electrode and the common electrode in a direction substantially perpendicular to the substrate surface. ) Method is considered to show the same tendency, and therefore, similarly to the VA method, the back side substrate is considered to be the first substrate and the display surface side substrate is assumed to be the second substrate.

  The first polarizing plate 10 includes at least a first polarizer 11, and in this embodiment, a first inner protective film 13 and a first outer protective film laminated on both inner and outer surfaces of the first polarizer 11. 14, the first conductive layer 12 laminated inside the first inner protective film 13, the first adhesive layer 15 for attaching the first polarizing plate 10 to the first substrate 41 of the liquid crystal cell 4, A first surface protective film 17 laminated on the first outer protective film 14 via a first weak adhesive layer 16 is provided.

A conventionally well-known thing can be used for the 1st polarizer 11, For example, the polyvinyl alcohol film by which the iodine complex or the dichroic dye was adsorbed-oriented can be used conveniently.
The first inner protective film 13 and the first outer protective film 14 are not particularly limited. For example, a film made of triacetyl cellulose resin, polyester resin, polycarbonate resin, cyclic polyolefin resin, (meth) acrylic resin, or the like is preferably used. it can.

The first conductive layer 12 preferably has a surface resistance value of 1.0 × 10 ¹² Ω / □ or less, and more preferably 1.0 × 10 ¹¹ Ω / □ or less. By providing the first conductive layer having such a configuration, the liquid crystal display panel can be more effectively prevented from being charged in the stacking process, and the orientation state of the liquid crystal molecules 431 can be further hardly changed.
In addition, the measuring method of a surface resistance value is as showing in the following Example.

  The material of the first conductive layer 12 is not particularly limited, and metal oxides such as ITO (Indium Tin Oxide) containing indium oxide as a main component and tin oxide added, polyacetylene, polypyrrole, polythiophene, A conductive polymer such as polyphenylene vinylene, a product obtained by adding a halogen or a halide to the conductive polymer, an ionic surfactant, or the like can be used.

  Further, the film forming method of the first conductive layer 12 is not particularly limited. For example, for metal oxide, a vapor deposition method such as a sputtering method, a vacuum evaporation method, an ion plating method, or a plasma CVD method is preferable. For the conductive polymer, a conventionally known coating method such as a bar coater, a blade coater, a spin coater, a reverse coater, a die coater, or a spray can be used.

  Moreover, it is preferable that the film thickness of the 1st conductive layer 12 is 100-300 nm.

  On the other hand, the second polarizing plate 20 includes at least the second polarizer 21. In the present embodiment, the second inner protective film 23 and the second outer protective layer laminated on both the inner and outer surfaces of the second polarizer 21. The film 24, the second adhesive layer 25 for attaching the second polarizing plate 20 to the second substrate 42 of the liquid crystal cell 4, and the second outer protective film 24 are laminated via the second weak adhesive layer 26. The second surface protective film 27 is provided.

  The second polarizing plate 20 may not have a conductive layer, but has a conductive layer (second conductive layer) from the viewpoint of more reliably suppressing charging of the liquid crystal cell 4. It is preferable. As the configuration of the conductive layer, the same configuration as that of the first conductive layer can be adopted.

  FIG. 2 is a flowchart showing an embodiment of a method for manufacturing a liquid crystal display device of the present invention. As shown in FIG. 2, the manufacturing method of the liquid crystal display device according to the present embodiment is a first polarization obtained by laminating a long first release film (first band-shaped carrier film) on a long first polarizing plate. A first polarizing plate original fabric preparation step S1 for preparing and unwinding a plate original fabric, and a first cutting step S2 for cutting the long first polarizing plate at predetermined intervals without cutting the first release film. A first polarizing plate pasting step S3a for sequentially sticking the first polarizing plate cut while peeling the first release film to the liquid crystal cell, and a long second polarizing plate on the long second polarizing plate. A second polarizing plate original fabric preparation step S4 for laminating a mold film (second band-shaped carrier film) to prepare and unwind the second polarizing plate original fabric, and the long film without cutting the second release film The second cutting step S5 for cutting the second polarizing plate at a predetermined interval, and peeling the second release film A second polarizing plate attaching step S3b for sequentially attaching the cut second polarizing plate to a liquid crystal cell (liquid crystal cell laminate) to which the first polarizing plate is attached, and a liquid crystal display panel manufactured by these steps. And an inspection step S7 for sequentially inspecting optically. That is, in this embodiment, lamination process S3 is provided with 1st polarizing plate sticking process S3a and 2nd polarizing plate sticking process S3b.

  3 to 6 are diagrams illustrating a schematic configuration of a manufacturing apparatus that performs the method of manufacturing the liquid crystal display device according to the present embodiment shown in FIG. Hereinafter, the manufacturing method and manufacturing apparatus of the liquid crystal display device according to the present embodiment will be described in detail with reference to FIGS.

  As shown in FIG. 3, the manufacturing apparatus of the liquid crystal display device according to the present embodiment is formed by laminating a long first release film 51 (first band-shaped carrier film) on a long first polarizing plate. First polarizing plate raw preparation means (first polarizing plate original fabric preparation step S1) for unwinding one polarizing plate original fabric 61, and the long first polarizing plate without cutting the first release film 51 First cutting means (first cutting step S2) for cutting at predetermined intervals, and first polarizing plate sticking for sequentially sticking the first polarizing plate cut while peeling the first release film 51 to the liquid crystal cell 4 Step (first polarizing plate pasting step S3a), turning means (not shown) for turning the liquid crystal cell 4 to which the first polarizing plate is attached 90 ° horizontally, and a long second polarizing plate Second polarizing plate raw material obtained by laminating a second release film 52 (second belt-shaped carrier film) The second polarizing plate original fabric preparation means (second polarizing plate original fabric preparation step S4) that prepares and unwinds 2 and the long second polarizing plate without cutting the second release film 62 are predetermined. A second cutting means (second cutting step S5) for cutting at intervals, and the second polarizing plate cut while peeling the second release film 52 to the liquid crystal cell 4 (1) attached with the first polarizing plate Second polarizing plate sticking means (second polarizing plate sticking step S3b) for sequentially sticking to the liquid crystal cell laminate) and inspection means (inspecting step S7) for optically sequentially inspecting the liquid crystal display panel Y produced by these steps. ). That is, in this embodiment, the laminating means includes a first polarizing plate sticking means and a second polarizing plate sticking means.

  Specifically explaining each step and each means, first, the first polarizing plate original fabric preparation means (first polarizing plate original fabric preparation step S1) is, as shown in FIG. (The lower surface side in FIG. 4) and the first first release film 51 formed by laminating the long first release film 51 (the upper surface side in FIG. 4) is prepared as a rolled state. , Configured to sequentially unwind.

  Next, as shown in FIG. 4, the first cutting means (first cutting step S <b> 2) includes a cutting means 130, and the long first polarizing plate 10 is separated at a predetermined interval using the cutting means 130. It is configured to cut into single wafers. However, the first release film 51 is not cut (so-called half cut), and even after the first polarizing plate 10 is cut into a sheet, the long first release film 51 It is configured to be a first strip that can be connected and rolled (a first strip in which a plurality of first polarizing plates cut at predetermined intervals are continuously formed on the first strip carrier film so as to be peelable). The In addition, the space | interval of a cutting | disconnection is made into the dimension according to the size of the liquid crystal cell 4 (1st board | substrate 41) used as bonding object.

And as shown in FIG. 4, a 1st polarizing plate sticking means (1st polarizing plate sticking process S3a) is provided with the 1st pressurization member and the 2nd pressurization member which were provided so that it might oppose, These Between the pressure members, the first polarizing plate 10 is fed simultaneously with the liquid crystal cell 4 separately prepared (supplied), and is sequentially attached (automatically attached) to the surface of the liquid crystal cell 4 so that the liquid crystal cell laminate X It is comprised so that. Here, the first pressure member in the present embodiment is a sticking roller 150a urged upward in FIG. 4 so as to press the first polarizing plate 10, and the second pressure member is a liquid crystal cell. 4 is a support roller 150b that contacts the lower surface of the roller 4 and conveys the first polarizing plate 10 and the liquid crystal cell 4 together with the first pressure member (sticking roller 150a) to the downstream side. Further, the first polarizing plate attaching means (first polarizing plate attaching step S3a) includes a knife edge 140, and the first release film 51 is provided immediately before the attaching roller 150a and the supporting roller 150b. The first polarizing plate 10 is attached to the liquid crystal cell 4 through the first adhesive layer 15 which is peeled off from the first polarizing plate 10 using 140 and exposed thereby.
Further, the first polarizing plate 10 is pasted in the first polarizing plate pasting step S3a on the back side substrate (first substrate) 41 which is less likely to attenuate the potential after being charged.

  On the other hand, as shown in FIG. 5, the second polarizing plate original fabric preparation means (second polarizing plate original fabric preparation step S4) includes a long second polarizing plate 20 (on the upper surface side in FIG. 5) and a long polarizing plate. The second polarizing plate original fabric 62 formed by laminating the second release film 52 (on the lower surface side in FIG. 5) is prepared as being wound in a roll shape, and is sequentially unwound.

  Next, as shown in FIG. 5, the second cutting means (second cutting step S <b> 5) includes a cutting means 230, and uses the cutting means 230 to cut the long second polarizing plate 20 at a predetermined interval. However, it is configured to be a single wafer. However, the second release film 52 is not cut (so-called half-cut), and even after the second polarizing plate 20 is cut into a sheet, the long second release film 52 is used. It is constituted so that it can be made into a second strip that can be connected and rolled (a second strip in which a plurality of second polarizing plates cut at predetermined intervals are continuously formed on the second strip carrier film so as to be peelable). . Note that the interval between the cuts is determined according to the size of the liquid crystal cell 4 (second substrate 42) to be bonded.

  And as shown in FIG. 5, the 2nd polarizing plate sticking means (2nd polarizing plate sticking process S3b) is provided with the 3rd pressurization member and the 4th pressurization member which were provided so that it might oppose, These Between the pressure members, the second polarizing plate 20 and the liquid crystal cell laminate X produced through the first polarizing plate pasting step S3a are simultaneously fed, and the second polarizing plate 20 is attached to the liquid crystal cell laminate X. The liquid crystal display panel Y is configured by being sequentially attached (automatically attached) to the surface. Here, the third pressure member in the present embodiment is a sticking roller 250a urged downward in FIG. 5 to press the second polarizing plate 20, and the fourth pressure member is a liquid crystal cell. This is a support roller 250b that contacts the lower surface of the laminate X and conveys the second polarizing plate 10 and the liquid crystal cell laminate X to the downstream side while sandwiching the second polarizing plate 10 and the liquid crystal cell laminate X together with the third pressure member (sticking roller 250a). The second polarizing plate pasting means (second polarizing plate pasting step S3b) includes a knife edge 240, and the second release film 52 is positioned immediately before the pasting roller 250a and the support roller 250b. The second polarizing plate 20 is peeled off from the second polarizing plate 20 using 240, and the second polarizing plate 20 is attached to the liquid crystal cell stack X through the exposed second adhesive layer 25. Further, the second polarizing plate 20 is pasted in the second polarizing plate pasting step S3b on the display surface side substrate (second substrate) 42 that is likely to attenuate the potential after being charged.

  As shown in FIG. 6, the inspection means (inspection step S7) sequentially inspects (automatic inspection) the liquid crystal display panel Y conveyed to the subsequent stage of the second polarizing plate attaching means (after the second polarizing plate attaching step S3b). Specifically, light is vertically irradiated from the light source 310 to the lower surface of the liquid crystal display panel Y, the transmitted light is captured by the CCD camera 330, image data is acquired, and the acquired image data is It is configured to perform image analysis processing, determine the presence or absence of defects, and determine good or defective products.

  The inspection means is arranged immediately after the second polarizing plate attaching means in order to shorten the tact time, that is, the inspection step S7 is performed with a relatively short interval from the attaching step S3b. Specifically, after the liquid crystal display panel Y undergoes the second polarizing plate pasting step S3b, the inspection is preferably performed within 1 minute, more preferably within 40 seconds, further preferably within 20 seconds, and particularly preferably within 10 seconds. Arranged to be implemented.

  FIG. 7 is a schematic cross-sectional view showing the configuration of the film provided with the first polarizing plate during the period from the first polarizing plate original fabric preparation step S1 to the first polarizing plate pasting step S3a. It is the cross-sectional schematic diagram which showed the structure of the film provided with the 1st polarizing plate between 2nd polarizing plate original fabric preparation process S4 to 2nd polarizing plate sticking process S3b.

  As shown in FIG. 7, in the first polarizing plate original fabric preparation step S <b> 1, a first polarizing plate original fabric 61 in which a long first polarizing plate 10 and a long first release film 51 are laminated, It has become.

  In the first cutting step S2, cuts are formed in the first polarizing plate 10 at predetermined intervals by the cutting means 130, but the first release film 51 remains long without being cut ( A first strip is produced).

  And in 1st polarizing plate sticking process S3a, said 1st release film 51 is peeled from the 1st polarizing plate 10, and only the 1st polarizing plate 10 is the 1st of the liquid crystal cell 4 via the 1st adhesion layer 15. FIG. The liquid crystal cell stack X is continuously manufactured by being sequentially stacked on the substrate 41.

  On the other hand, as shown in FIG. 8, in the second polarizing plate original fabric preparation step S4, the second polarizing plate original fabric in which the long second polarizing plate 20 and the long second release film 52 are laminated. 62.

  Further, in the second cutting step S5, cuts are formed in the second polarizing plate 20 at predetermined intervals by the cutting means 230, but the second release film 52 remains long without being cut. (A second strip is produced).

  And in 2nd polarizing plate sticking process S3b, the said 2nd release film 52 is peeled from the 2nd polarizing plate 20, and only the 2nd polarizing plate 20 is the 2nd of the liquid crystal cell 4 via the 2nd adhesion layer 25. The liquid crystal display panel Y is continuously manufactured by sequentially stacking on the substrate 42.

  According to the manufacturing apparatus and the manufacturing method of the liquid crystal display device according to the present embodiment, the first procedure in which the conductive layer is provided on the first substrate (back side substrate) that is difficult to attenuate the potential after being charged, as described above. The polarizing plate is attached, and then the second polarizing plate is attached to the second substrate (display surface side substrate) that is likely to attenuate the potential after being charged, thereby suppressing the charging of the liquid crystal cell. Then, even when the optical inspection process as described above is performed immediately after the pasting process (lamination process), the inspection can be performed without being adversely affected by the charging of the liquid crystal cell. Tact time can be shortened without erroneous detection. As a result, a VA liquid crystal display panel can be continuously manufactured at high speed, and the production efficiency can be greatly increased.

  Although the reason why the charging of the liquid crystal cell is suppressed is not certain, in the VA liquid crystal cell according to the present embodiment, the back side substrate (first substrate) is between the circuit part such as the gate wiring and the pixel electrode. It is presumed that once the liquid crystal cell is charged by friction with the support roller, the charged state will be sustained because the potential is not easily attenuated once charged.

Specifically, the charge accumulated on the substrate surface due to electrostatic induction during charging gradually moves to the pixel electrode and the circuit part, and both of them are in a state where the charge is accumulated. Although the charge is discharged quickly, the pixel electrode is electrically blocked from the circuit part by the switching element (thin film transistor) in the non-driven state, so that the charge cannot flow to the circuit part side and remains accumulated. It is easy to think that, due to such factors, it is difficult to attenuate the potential after the back side substrate in the above embodiment is charged.
According to the apparatus and method of this embodiment, the polarizing plate is attached to the back side substrate (first substrate) prior to the display surface side substrate (second substrate), and thus the first substrate having such a configuration and It is presumed that friction with the sticking roller is prevented and charging of the liquid crystal cell is suppressed.

  In the present invention, it is obvious that conventionally known technical matters can be appropriately employed within a range where the effects of the invention are not significantly impaired.

  For example, in the present embodiment, the case where the first conductive layer is provided between the first pressure-sensitive adhesive layer and the first inner protective film has been described. It is not limited, It can provide in the arbitrary positions of a 1st polarizing plate, ie, the arbitrary positions from a 1st surface protection film to a 1st adhesion layer.

  In addition to the above-described layers, the first polarizing plate and the second polarizing plate may be any layer having other optical functions or physical functions, for example, a brightness enhancement layer, a retardation layer, an antireflection layer. Etc. may be provided as appropriate.

Furthermore, in the said embodiment, the polarizing plate which is a sheet body is this mold release by employ | adopting a half cut in a cutting process using a long 1st release film and a long 2nd release film. Although it was set as the state connected with the film and it was made to roll-roll as a elongate body just before sticking also after this cutting process, this invention is not limited to such an aspect.
For example, a strip having a longer polarizing plate than the liquid crystal cell is supplied to the strip carrier film so that the strip is peeled off, and the strip carrier film is folded at the knife edge so that the long polarizer is partially formed from the strip carrier film. After peeling off the part of the long polarizing plate attached to the substrate of the sequentially supplied liquid crystal cell, the part of the attached long polarizing plate is a length corresponding to the liquid crystal cell. You may make it cut | disconnect. Such an automatic sticking method is not particularly limited, and for example, a method disclosed in Japanese Patent Laid-Open No. 2005-37418 can be adopted. Also in this automatic sticking method, when the inspection process (inspection means) for inspecting the liquid crystal display panel is provided after the process (lamination process) for producing the liquid crystal display panel (after the lamination means), the technique of the present invention By applying the idea, the effect of the present invention that the tact time can be shortened without causing erroneous detection in panel inspection is effectively exhibited, and high-speed continuous manufacturability of the liquid crystal display panel is guaranteed. It becomes.

  Moreover, in the said embodiment, although the sticking roller and the support roller were employ | adopted as a pressurization member, this invention is not limited to this, For example, you may employ | adopt an elastic plate-shaped body etc. as a pressurization member.

Furthermore, in the manufacturing method according to the above-described embodiment, the case where a VA liquid crystal cell is used as the liquid crystal cell to which the polarizing plate is attached is described. As described above, the present invention is applied to such an embodiment. The present invention is not limited, and can be applied to other types of liquid crystal cells.
Hereinafter, Embodiment 2 of the present invention in which an in-plane switching (IPS) type liquid crystal cell is used as the liquid crystal cell will be specifically described.

(Embodiment 2)
FIG. 9 is a schematic cross-sectional view of a liquid crystal display panel using IPS liquid crystal cells manufactured continuously at high speed in the second embodiment. 9, the same members as those in FIG. 1 are denoted by the same reference numerals, and the description thereof may be omitted.
As shown in FIG. 9, the IPS liquid crystal cell 4 ′ used in the second embodiment has a liquid crystal layer 43 ′ sandwiched between a pair of substrates 41 ′ and 42 ′, like the other liquid crystal cells. It is configured. Of these pair of substrates, the display surface side substrate 42 ′ located on the display surface side of the liquid crystal cell 4 ′ does not have a conductive member such as a pixel electrode or a common electrode, while the back surface of the liquid crystal cell 4 ′. The rear side substrate 41 ′ located on the side has a configuration including a pixel electrode and a common electrode for driving the liquid crystal layer 43 ′, and is between the pixel electrode and the common electrode, that is, with respect to the substrate surface. Thus, the liquid crystal layer 43 ′ is driven by applying an electric field in a substantially parallel direction.

  Specifically, the back-side substrate 41 ′ includes a plurality of gate wirings, a plurality of common electrode wirings, a plurality of gate wirings, a plurality of common electrode wirings, and a gate insulating film on a transparent substrate 411 such as glass or plastic. A circuit unit including a plurality of source wirings provided orthogonally via the thin film transistor (TFT) 412 as a plurality of switching elements provided at intersections of the plurality of gate wirings and the plurality of source wirings, A protective film 413 provided on the plurality of switching elements (thin film transistors) 412, and a contact hole provided on the protective film 413 and formed so as to penetrate the protective film. A plurality of transparent electrodes (pixel electrodes) 414 respectively connected to the protective film 413 and penetrating through the gate insulating film and the protective film. Provided on the plurality of common electrodes 416 connected to each of the plurality of common electrode wirings, the plurality of transparent electrodes (pixel electrodes) 414, and the plurality of common electrodes 416 through contact holes formed to be The alignment film 415 is provided.

  The thin film transistor 412 includes a gate electrode, a semiconductor layer facing the gate electrode with a gate insulating film interposed therebetween, and a source electrode and a drain electrode individually connected to the semiconductor layer. A gate wiring is connected to the gate electrode, a source wiring is connected to the source electrode, and a pixel electrode 414 is connected to the drain electrode.

  On the other hand, the display surface side substrate 42 'is formed on a transparent substrate 421 such as glass or plastic, a color filter 422, an overcoat layer (not shown) provided on the color filter 422, and the overcoat layer. And an alignment film 425 provided on the substrate.

  The liquid crystal layer 43 ′ constituting the liquid crystal cell 4 ′ is generally composed of nematic liquid crystal molecules 431 ′ having a positive dielectric anisotropy (Δε> 0) or a negative dielectric anisotropy (Δε <0). The The liquid crystal layer 43 ′ is driven by applying an electric field between the pixel electrode 414 and the common electrode 416 in the back side substrate 41 ′ in a direction substantially parallel to the substrate surface. That is, when the voltage is less than the threshold voltage, the major axis of the liquid crystal molecules 431 ′ is parallel to the substrate surface and parallel or orthogonal to the absorption axis of the first polarizer 11 of the first polarizing plate 10. Therefore, the incident linearly polarized light from the backlight side does not receive the birefringence effect when passing through the liquid crystal layer 43 ′. On the other hand, when the voltage is equal to or higher than the threshold voltage, the major axis of most liquid crystal molecules 431 ′ excluding the vicinity of the substrate surface is in-plane direction parallel to the substrate surface by a predetermined angle according to the magnitude of the voltage. (Inclination with respect to the absorption axis of the first polarizer 11 of the first polarizing plate 10), the incident linearly polarized light undergoes a birefringence effect and changes to elliptically polarized light. As a result, a certain amount of light corresponding to the rotation angle of the liquid crystal molecules passes through the polarizer 11 of the first polarizing plate 10.

  As described above, in the second embodiment employing the IPS liquid crystal cell, the display surface side substrate 42 ′ does not have a conductive member such as a pixel electrode or a common electrode as compared with the rear surface side substrate 41 ′. In this configuration, potential decay after charging is difficult to occur. Therefore, in the second embodiment, the display surface side substrate 42 ′ is the first substrate to which the polarizing plate is to be attached first, while the back surface side substrate 41 ′ is the second substrate.

  As a result, in the method and the apparatus for manufacturing the liquid crystal display device of Embodiment 2, the display surface side substrate is the first substrate, the display surface side polarizing plate is the first polarizing plate, the back side substrate is the second substrate, and the back surface. The polarizing plate on the side is the second polarizing plate, but the other configurations are the same as those of the manufacturing method and manufacturing apparatus of the first embodiment, and thus the description thereof is omitted.

  According to the method of manufacturing the liquid crystal display device according to the second embodiment, the above-described procedure, that is, the display surface side substrate 42 ′ is the first substrate, and the first polarizing plate is attached to the first substrate. Then, the back side substrate 41 ′ is used as the second substrate, and the second polarizing plate is attached to the second substrate, so that the charging of the liquid crystal cell 4 ′ is suppressed. Even when the optical inspection process of the liquid crystal display panel is performed immediately after the pasting process, the inspection can be performed without being adversely affected by the charging of the liquid crystal cell. Can be shortened. Therefore, it becomes possible to manufacture an IPS liquid crystal display panel continuously at high speed, and the production efficiency can be greatly increased.

The reason why charging of the liquid crystal cell is suppressed is not clear, but in the second embodiment using the IPS liquid crystal cell, the display surface side substrate does not have a conductive member such as a pixel electrode or a common electrode. It is presumed that once charged, the potential is hardly attenuated, and when the liquid crystal cell is charged by friction with the sticking roller, the charged state is maintained.
According to the apparatus and method of the second embodiment, the polarizing plate is attached to the display surface side substrate (first substrate) before the back surface side substrate (second substrate), whereby the display surface having the above-described configuration. It is presumed that friction between the side substrate and the sticking roller is prevented, and charging of the liquid crystal cell is suppressed.

  In the IPS method, in addition to erroneous detection of the inspection process, electrostatic breakdown of the switching element (thin film transistor) may be a problem. The breakdown mechanism of the switching element in the IPS liquid crystal cell is that an excessive current flows to the switching element when the electric charge accumulated on the display surface side substrate (first substrate) is discharged toward the back side substrate (second substrate). This is considered to destroy the switching element. According to the apparatus and method of this embodiment, it is estimated that the electrostatic breakdown of such a switching element is also suppressed.

  In the present invention, as long as the effects of the present invention are not hindered, other processes are appropriately provided between the respective processes (for example, between the laminating means (laminating process) and the inspecting means (inspecting process)). Means (process) can be interposed.

  EXAMPLES Next, although an Example is given and this invention is demonstrated in more detail, this invention is not limited to these.

(Measurement of easy charging of liquid crystal cell substrate)
Ease of charging was measured for a CF substrate (a substrate provided with a color filter) and a TFT substrate (a substrate provided with a thin film transistor) constituting a VA liquid crystal cell. Specifically, after both ends of the substrate are fixed on a PTFE (polytetrafluoroethylene) support base, a PTFE disk and a SUS304 disk are stacked (thickness 0.8 mm, φ250 mm). The cloth was rubbed several times on the SUS304 disk side to charge it, and the SUS304 disk was attached to the fixed substrate, and then separated from the substrate. During this series of operations, the charge amount of the substrate was measured from the back side of the substrate attachment surface using a charge amount measuring device (manufactured by SMC, IZH10). The results are shown in Table 1 below and FIG.

  As shown in Table 1 and FIG. 10, it can be seen that the TFT substrate is in a charged state for a while even after the PTFE disks are separated. On the other hand, it can be seen that the CF substrate returns to the initial state immediately after the PTFE disks are separated. In other words, in the VA liquid crystal cell used in this test, the TFT substrate is easily charged, that is, the first substrate that is not easily attenuated after charging, and the CF substrate is not easily charged, that is, the second substrate that is easily attenuated after charging. It turns out that it corresponds to. Hereinafter, in this example and the comparative example, the test was performed using the TFT substrate as the first substrate and the CF substrate as the second substrate.

<Example 1>
Using the apparatus described as the first embodiment above, after performing the first polarizing plate pasting step (S3a) for pasting the first polarizing plate from the long side to the rectangular liquid crystal cell, After rotating (turning) 90 degrees in the horizontal direction and aligning (positioning), the second polarizing plate attaching step (S3b) for attaching the second polarizing plate to the liquid crystal cell from the short side is then performed. 2000 display panels were continuously manufactured. The sticking speed of each polarizing plate and the transport speed of the liquid crystal cell were 200 mm / s. The specifications of the materials and equipment used are as follows.
In addition, the measurement of the surface resistance value of the conductive layer included as a part of the polarizing plate original fabric was performed according to JIS K 6911 5.13. Specifically, a polarizing plate original fabric is cut into a size of 150 mm × 150 mm to obtain a test piece, and the test piece is made by Mitsubishi Chemical Analytech Co., Ltd., high resistance / low efficiency meter Hirester UP (model: MCP-HT450) And the surface resistance value was measured using a probe (model: MCP-SWB01).
Moreover, as a sticking speed, it was set as the measured value of the speed which a polarizing plate and a liquid crystal cell pass between the following sticking rollers and a support roller. That is, the sticking speed of the polarizing plate was the same as the transport speed of the liquid crystal cell.

(Use materials and equipment)
・ Liquid crystal cell: Vertical alignment type (screen size 32 inches)
・ First polarizing plate original and second polarizing plate original: manufactured by Nitto Denko Corporation, trade name “VEG1724DU-AC” (conducting layer: including surface resistance value 1.0 × 10 ¹¹ Ω / □, film thickness 150 μm)
・ Applying roller (applying side): manufactured by Kaki Roller Manufacturing Co., Ltd., model “LM4070E”, made of conductive silicon, hardness 70 °, surface resistance value 1.0 × 10 ⁶ Ω / □, roll diameter 100 mm
Support roller (support side): manufactured by Kaki Roller Manufacturing Co., Ltd., model “Black EC-N970”, made of conductive urethane, hardness 70 °, surface resistance value 1.0 × 10 ⁸ Ω / □, roll diameter 200 mm

<Examples 2 to 4>
2000 liquid crystal display panels were produced in the same manner as in Example 1 except that the polarizing plate sticking speed and the liquid crystal cell transport speed were 150 mm / s, 100 mm / s, and 50 mm / s, respectively.

<Comparative Example 1>
The pasting order is the same as in Example 1, that is, the second polarizing plate pasting step (S3b) is performed, and then the first polarizing plate pasting step (S3a) is performed. 2000 liquid crystal display panels were produced.

<Comparative Examples 2-4>
2000 liquid crystal display panels were produced in the same manner as in Comparative Example 1 except that the polarizing plate sticking speed and the liquid crystal cell transport speed were 150 mm / s, 100 mm / s, and 50 mm / s, respectively.

<Comparative Example 5>
Based on the measurement result of the charge amount of the liquid crystal cell substrate (Table 1, FIG. 10), the time interval between the second polarizing plate attaching step (S3b) and the first polarizing plate attaching step (S3a) is 600. Except that it was set to 2 seconds, 2000 liquid crystal display panels were produced similarly to the comparative example 1.

(Measurement of charge amount)
In Examples and Comparative Examples, a charge amount measuring device (manufactured by Keyence Corporation, model: SK-200) was installed immediately after each attaching step, the amount of charge after attaching was measured, and an average value for 2000 liquid crystal display panels Was calculated. The results are shown in Table 3 below.

(Evaluation in the inspection process)
Moreover, about the liquid crystal display panel produced by the Example and the comparative example, the test process was implemented with the optical test | inspection apparatus arrange | positioned in the downstream of the sticking process of a back | latter stage. In the inspection process, light is irradiated from the lower surface side of the liquid crystal display panel, the light transmission state that should be blocked by the CCD camera disposed on the upper surface side is detected, and image analysis processing is performed based on the detection result. It was.

  Here, Table 2 below shows the pasting steps, the inspection steps, and the time required between the steps in the above-described examples and comparative examples.

  In the above inspection process, the results are shown in Table 3 below, where x is a case where erroneous detection that appears to be caused by uneven alignment of liquid crystal molecules occurs, and ○ is a case where no erroneous detection occurs. .

From the results shown in Table 3, in Comparative Examples 1 to 4 in which the pasting step S3b was previously performed on the CF substrate (second substrate) that is likely to attenuate the potential after charging, erroneous detection occurred in the inspection step. In Examples 1 to 4 in which the pasting step S3a was previously performed on the TFT substrate (first substrate) which is less likely to be attenuated later, it is recognized that no erroneous detection occurred in the inspection step.
Further, in Comparative Example 5, even when the pasting step S3b for the CF substrate (second substrate) that is likely to be attenuated after charging is performed first, the inspection step is performed with a time interval of 600 seconds. It has been confirmed that false detection can be prevented, but in this case, the tact time is extremely longer than in Examples 1 to 4 and Comparative Examples 1 to 4, and the production efficiency is greatly reduced. Was.

(Comparative Examples 6 to 10)
Next, by changing the gap (gap) between the application roller (polarizing plate side) and the support roller (substrate side) in the previous and subsequent application steps, the contact area between the substrate and the support roller is changed, The same test as in Example 1 and Comparative Example 1 was performed. The test conditions and test results are shown in Table 4 below.

From the results shown in Table 4, even when the pasting step S3b is performed on the CF substrate (second substrate) that tends to attenuate the potential after charging, the contact area between the substrate and the roller is reduced to reduce the liquid crystal cell. It is possible to suppress the charging (Comparative Examples 9 and 10), but in such a case, it can be seen that the contact pressure between the substrate and the roller is lowered and the bubbles are in a state of being caught. Conversely, when the contact pressure between the substrate and the roller is increased by increasing the contact area between the substrate and the roller to suppress the entrapment of bubbles (Comparative Examples 1 and 6 to 8), the liquid crystal cell is charged. Thus, it can be seen that erroneous detection occurs in the inspection process.
On the other hand, in Example 1, the contact area between the substrate and the roller is increased to increase the contact pressure between the substrate and the roller, thereby suppressing the entrapment of bubbles and at the same time suppressing the charging of the liquid crystal cell. It can be seen that false detection in the inspection process can be prevented.

DESCRIPTION OF SYMBOLS 1 Manufacturing method 4 of a liquid crystal display device, 4 'Liquid crystal cell 10 1st polarizing plate 11 1st polarizer 12 Conductive layer 13 1st inner side protective film 14 1st outer side protective film 15 1st adhesion layer 16 1st weak adhesion layer 17 First surface protective film 20 Second polarizing plate 21 Second polarizer 23 Second inner protective film 24 Second outer protective film 25 Second adhesive layer 26 Second weak adhesive layer 27 Second surface protective films 41, 41 ′ Back side Substrate 42, 42 'Display surface side substrate 43, 43' Liquid crystal layer 51 First release film 52 Second release film 61 First polarizing plate original 62 Second polarizing plate original 150a, 250a Adhesive rollers 150b, 250b Roller 411, 421 Glass substrate 412 TFT
413 Interlayer insulating film 414, 424 Transparent electrode (pixel electrode)
415, 425 Alignment film 416 Common electrode 422 Color filter 431, 431 ′ Liquid crystal molecule S1 First polarizing plate original fabric preparation step S2 First cutting step S3 Lamination step S3a First polarizing plate pasting step S3b Second polarizing plate pasting step S4 Two polarizing plate original fabric preparation step S5 Second cutting step S7 Inspection step X Liquid crystal cell laminate Y Liquid crystal display panel

Claims (11)

A laminating step of laminating polarizing plates having the same or different structures on both front and back surfaces of a liquid crystal cell provided with a liquid crystal layer between a first substrate and a second substrate to form a liquid crystal display panel; A method for manufacturing a liquid crystal display device, comprising:
The first polarizing plate attaching step of attaching the first polarizing plate to the first substrate that is less likely to be attenuated after charging than the second substrate, and the first polarizing plate attaching step, A method of manufacturing a liquid crystal display device, comprising: a second polarizing plate attaching step of attaching a second polarizing plate to the second substrate that is more likely to attenuate the potential after charging than the substrate.
The first polarizing plate pasting step supplies a first strip in which a plurality of first polarizing plates cut at predetermined intervals are continuously formed on the first strip carrier film so as to be peelable along the longitudinal direction. A step of folding the first strip carrier film at the edge and sequentially peeling the first polarizing plate from the first strip carrier film, and attaching the peeled first polarizing plate to the first substrate of the liquid crystal cell that is sequentially supplied, or A first strip having a longer length than the liquid crystal cell is provided on the first strip carrier film so as to be peelable, and the first strip carrier film is folded back by a knife edge. The long first polarizing plate is partially peeled off, and the part of the peeled long first polarizing plate is attached to the first substrate of the liquid crystal cell that is sequentially supplied, and then the attached long length The first polarizing plate part A step of cutting a length corresponding to the crystal cell,
The second polarizing plate pasting step supplies a second strip in which a plurality of second polarizing plates cut at predetermined intervals are continuously formed on the second strip carrier film so as to be peelable along the longitudinal direction. The second band-shaped carrier film is folded back at the edge, the second polarizing plate is sequentially peeled from the second band-shaped carrier film, and the peeled second polarizing plate is sequentially supplied to the liquid crystal cell to which the first polarizing plate is attached. A step of attaching to the second substrate, or a second polarizing plate having a longer length than the liquid crystal cell is formed on the second strip carrier film so as to be peelable, and the second strip carrier film is formed with a knife edge. The long second polarizing plate was partially peeled off from the second belt-like carrier film, and the peeled long second polarizing plate portion was attached to the first polarizing plate that was sequentially supplied. On the second substrate of the liquid crystal cell After Attach a step of cutting the portion of the second long polarizing plate affixed in length corresponding to the liquid crystal cell,
2. The method of manufacturing a liquid crystal display device according to claim 1, wherein the inspection step is a step of optically sequentially inspecting the liquid crystal display panel conveyed after the second polarizing plate pasting step.
In the first polarizing plate pasting step, the first pressure member and the liquid crystal cell side pressurize the first polarizing plate and the liquid crystal cell from the first polarizing plate side, with at least a part of them being overlapped with each other. Between the first pressure member and the second pressure member, and the first polarizing plate and the liquid crystal cell are moved relative to each other. A method for manufacturing a liquid crystal display device according to claim 1 or 2.
In the second polarizing plate pasting step, the liquid crystal cell to which the first polarizing plate is pasted and the second polarizing plate are pressed from the second polarizing plate side with at least a part of them being overlapped with each other. The first polarizing plate is sandwiched between the third pressure member and the fourth pressure member that pressurizes from the first polarizing plate side attached to the liquid crystal cell, and the third pressure member and the fourth pressure member. The method for producing a liquid crystal display device according to claim 1, wherein the method is performed by relatively moving the laminated liquid crystal cell and the second polarizing plate.
The first substrate includes a plurality of gate wirings, and a plurality of gate wirings and a plurality of source wirings provided orthogonally via an insulating film, the plurality of gate wirings and the plurality of source wirings A plurality of switching elements provided at intersections with the plurality of pixel electrodes connected to the plurality of switching elements,
The second substrate has a common electrode provided to face the plurality of pixel electrodes,
The liquid crystal layer is driven by applying an electric field between the pixel electrode and the common electrode in a direction substantially perpendicular to the substrate surfaces of the first substrate and the second substrate. ,
The manufacturing method of the liquid crystal display device in any one of Claims 1-4.
The first substrate does not include a conductive member,
6. The second substrate includes a pixel electrode and a common electrode for driving a liquid crystal layer by applying an electric field in a direction substantially parallel to the substrate surface. A method for manufacturing a liquid crystal display device according to any one of the above.
The method for manufacturing a liquid crystal display device according to claim 1, wherein the first polarizing plate is provided with a conductive layer having a surface resistance value of 1.0 × 10 ¹² Ω / □ or less.
Laminating means for forming a liquid crystal display panel by laminating polarizing plates having the same or different structures on both front and back surfaces of a liquid crystal cell provided with a liquid crystal layer between a first substrate and a second substrate, and optically operating the liquid crystal display panel An apparatus for manufacturing a liquid crystal display device comprising an inspection means for automatically inspecting,
The laminating means is disposed at a stage subsequent to the first polarizing plate attaching means, a first polarizing plate attaching means for attaching the first polarizing plate to the first substrate, which is less likely to attenuate the potential after charging than the second substrate, An apparatus for manufacturing a liquid crystal display device, comprising: a second polarizing plate attaching means for attaching a second polarizing plate to the second substrate, which is more easily attenuated after charging than the first substrate.
The first polarizing plate pasting means is configured to remove a first belt-shaped carrier film from a belt-like body in which a plurality of first polarizing plates cut at predetermined intervals are continuously formed on the first belt-like carrier film so as to be peelable along the longitudinal direction. A knife edge that is folded to sequentially peel the first polarizing plate from the first band-shaped carrier film, and a sticking means for sticking the peeled first polarizing plate to the first substrate of the liquid crystal cell that is sequentially supplied, Alternatively, the first band-shaped carrier film is folded from the first band-shaped body in which the first polarizing plate longer than the liquid crystal cell is formed to be peelable on the first band-shaped carrier film, and the first band-shaped carrier film has a long first length. A knife edge that partially peels one polarizing plate, a pasting means for sticking the peeled portion of the long first polarizing plate to the first substrate of the liquid crystal cell that is sequentially supplied, and a long first polarizing plate Part of The are those in which a cutting means for cutting a length corresponding to the liquid crystal cell,
The second polarizing plate affixing means is configured to remove a second belt-shaped carrier film from a belt-like body in which a plurality of second polarizing plates cut at predetermined intervals are continuously formed on the second belt-shaped carrier film so as to be peelable along the longitudinal direction. To the second substrate of the liquid crystal cell to which the first polarizing plate is attached, the knife edge for sequentially peeling the second polarizing plate from the second strip carrier film and the peeled second polarizing plate are sequentially supplied. The second belt-like carrier film is folded from a second belt-like body having a sticking means for sticking or a second polarizing plate having a longer length than the liquid crystal cell formed on the second belt-like carrier film. A liquid crystal cell to which the first polarizing plate is attached, wherein a knife edge for partially peeling the second polarizing plate from the second strip carrier film and a portion of the peeled long second polarizing plate are sequentially supplied. The first A sticking means to be pasted to the substrate, which part of the second long polarizing plate and a cutting means for cutting a length corresponding to the liquid crystal cell,
9. The apparatus for manufacturing a liquid crystal display device according to claim 8, wherein the inspecting means is means for optically sequentially inspecting the liquid crystal display panel that has been conveyed after the second polarizing plate attaching means.
The first polarizing plate affixing means sandwiches the first polarizing plate and the liquid crystal cell in a state where at least a part of them is overlapped with each other. The first polarizing plate is attached to the first substrate by moving the first polarizing plate and the liquid crystal cell relative to the first pressing member and the second pressing member. 10. The apparatus for manufacturing a liquid crystal display device according to claim 8, wherein the apparatus is configured to be configured to be able to.
  The second polarizing plate pasting means sandwiches the liquid crystal cell on which the first polarizing plate is pasted and the second polarizing plate in a state where at least a part of them is overlapped with each other, and the third on the second polarizing plate side. A pressure member and a fourth pressure member on the first polarizing plate attached to the liquid crystal cell are provided, and the first polarizing plate is laminated on the third pressure member and the fourth pressure member. The liquid crystal according to any one of claims 8 to 10, wherein the liquid crystal cell and the second polarizing plate are relatively moved so that the second polarizing plate can be attached to the second substrate. Display device manufacturing equipment.

Images