JP2009204780A - Liquid crystal panel and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal panel can add a charge preventive function to the liquid crystal panel, and can enhance a flexural strength, and provide a method of manufacturing the same. <P>SOLUTION: The liquid crystal panel is formed by bonding two sheets of glass substrates 1, 21, and has a flexibility. The liquid crystal panel 54 includes a transparent conductive film 65 on an outer main face in at least one of the glass substrates 1, 21, and on end parts and side faces 64 of the glass substrates 1, 21. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a liquid crystal panel and a manufacturing method thereof, and more particularly to a liquid crystal panel using a flexible substrate and a manufacturing method thereof.

  In recent years, thinning of liquid crystal panels for the purpose of versatility such as weight reduction and flexibility has been studied. Recently, in order to realize weight reduction and flexibility, a method of thinning a glass substrate used for a liquid crystal panel to about 0.1 mm to 0.2 mm has been widely used. However, as the glass substrate is made thinner, the strength of the glass end face and side surface has become an important factor that determines the allowable strength of the entire liquid crystal panel. It is necessary to suppress the decrease factor of the bending strength at the end.

  In ordinary liquid crystal panels, a large glass substrate is used. An alignment film is formed on each of the array substrate on which active elements are formed and the counter substrate on which color filters are formed, and liquid crystal is filled between the alignment films on both substrates. Is produced. Thinning of a general liquid crystal panel is performed before a liquid crystal is injected after being cut out from a large glass substrate into a single panel, and is performed by thinning the bonded glass substrate by polishing or etching. In order to cut out from a large glass substrate into a single panel, a scribing wheel is provided at a predetermined position using a scribe wheel, and then a single panel is divided by a break process. At the edge of the glass substrate of the divided single panel, there are a large number of scribe wheel traces and cracks of about several micrometers (μm) called microcracks.

  Conventionally, as a countermeasure against such a problem, a method of removing microcracks by polishing the surface of a glass substrate with a grindstone or the like (for example, refer to Patent Document 1), or a reinforcing agent or powdery form containing 60% or more of titanium oxide. The strength of the glass plate is improved by spraying a reinforcing agent on the edge of the glass substrate, simultaneously heating and melting at 650 to 900 ° C. with laser light or halogen light, and diffusing into the glass, thereby suppressing the development of microcracks. (For example, refer to Patent Document 2). In addition, a silica sol obtained by hydrolyzing or polycondensing a silica precursor is formed on the entire surface of the substrate, and the glass substrate is improved in bending strength by contacting with water after sintering at about 150 ° C. (for example, patents) Reference 3). In addition, high strength glass can be obtained by irradiating a glass substrate with an ultrashort pulse laser to form a heterogeneous phase (see, for example, Patent Document 4), or glass having a depth of 5 μm or more from the glass substrate surface. Glass is strengthened by preventing the development of microcracks by implanting hydrogen ions or helium ions over the entire surface to provide a modified region (see, for example, Patent Document 5).

JP 2001-6161 A JP 2006-282492 A JP-A-2005-247487 JP 2003-286048 A Special table 2007-523027 gazette

  However, in Patent Document 1, since the glass substrate is damaged by polishing when the glass substrate is thinned, it is difficult to use this method for a thin liquid crystal panel. Moreover, in patent document 2, although the reinforcement | strengthening agent which contains 60% or more of titanium oxide is used in order to strengthen the end surface of a glass substrate, since the processing temperature for diffusing these is very high with 650-900 degreeC, The influence of heat resistance on the members constituting the liquid crystal panel becomes a problem. Furthermore, in Patent Documents 3, 4, and 5, it is not possible to eliminate the influence on the bending strength of the liquid crystal panel with respect to the ruled lines and microcracks by the scribe wheel used when the liquid crystal panel is cut into a single piece. Thus, conventionally, in the standard manufacturing process of a liquid crystal panel, the bending strength due to the influence of the glass substrate end face of the liquid crystal panel has not been considered.

  The present invention has been made to solve these problems, and an object of the present invention is to provide a liquid crystal panel capable of adding an antistatic function to the liquid crystal panel and improving the bending strength, and a method for manufacturing the same.

  In order to solve the above-described problems, a liquid crystal panel according to the present invention is a flexible liquid crystal panel formed by bonding two glass substrates, and an outer main surface of at least one glass substrate and a glass substrate. It comprises a paint having transparent conductivity applied to at least two glass ends and side surfaces facing each other in plan view.

  According to the present invention, in a flexible liquid crystal panel formed by laminating two glass substrates, at least two glass edges opposed to the outer main surface of at least one glass substrate in plan view of the glass substrate. Since the coating having transparent conductivity applied to the part and the side surface is provided, an antistatic function can be added to the liquid crystal panel and the bending strength can be improved.

  Embodiments of the present invention will be described below with reference to the drawings.

<Embodiment 1>
1A and 1B are views for explaining the structure of a liquid crystal panel according to Embodiment 1 of the present invention, in which FIG. 1A is a perspective view, FIG. 1B is a sectional view taken along a dotted line TT ′ in FIG. The front view seen from the surface side, (d) is the perspective view which showed the case where the panel of (a) is curved and used. In this liquid crystal panel, a glass substrate 1 and a glass substrate 21 are bonded together, a liquid crystal 51 is sealed between the bonded substrates by a sealing material 12, and the liquid crystal 51 has an optical characteristic by an electrode formed on any substrate. The image is displayed by being controlled. In the first embodiment, a transmission-type IPS (In Plane Switching) liquid crystal panel will be described in particular.

  The glass substrate 1 is an array substrate in which elements and electrodes for controlling liquid crystal are formed on the inner main surface facing the glass substrate 21, and the glass substrate 21 is a color filter substrate in which a color filter is formed on the inner surface. . These substrates are thin and have flexibility such as 0.1 to 0.7 mm. Pixels having electrodes and filters are arranged on a matrix to form a display area. A part of the surface of the glass substrate 1 on which the elements are formed is exposed without being covered with the glass substrate 21, and a terminal 13 is provided on the exposed portion. An electrical signal for image display is supplied to an external pixel through this terminal 13.

  In the glass substrate 21 of the liquid crystal panel of the first embodiment, an antistatic functional film 65 made of a transparent conductive coating film is formed on the outer surface opposite to the inner surface where the liquid crystal is sealed, that is, on the display surface side. . The antistatic function film 65 is for preventing the quality of the liquid crystal display from being deteriorated due to the glass substrate 21 being charged. In particular, the effect of preventing deterioration is remarkable with respect to the IPS liquid crystal panel having no electrode on the glass substrate 21 on the color filter substrate side. Further, the glass substrate 21 of the liquid crystal panel of the first embodiment is also provided with the antistatic functional film 65 on the side surface and the end portion thereof. The end portion is an edge portion where the side surface and the main surface intersect. As shown in the T-T ′ cross-sectional view of FIG. 1B, the antistatic function film 65 may wrap around the periphery of the glass substrate 1 on the side opposite to the display surface. Thereby, the antistatic function film 65 is reliably formed also at the end of the glass substrate 1. The antistatic function film 65 may be applied to the entire surface of the display surface side and the back surface side. However, particularly in the case of a transmissive liquid crystal display panel, the wraparound region is kept between the display region and the periphery of the panel. It is good not to form in the display area of the back substrate. As a result, the antistatic function film 65 is reliably attached to the edge of the back substrate, while the antistatic function film 65 attached to the display area is only on one surface, and even if the antistatic function film 65 absorbs a large amount of light. A bright display can be obtained.

  The liquid crystal panel is generally formed by bonding two rectangular glass substrates as shown in the figure. The front view of FIG. 1C shows that the antistatic function film 65 is formed not only on the front surface that is the display surface but also on the side surfaces that are located on the opposite sides of the rectangle X1 and X2. . As described above, on the glass substrate of the first embodiment, when the panel is viewed from the front, the antistatic functional film 65 is formed on at least two opposing side surfaces located at the top and bottom or the left and right ends and the ends thereof. The Further, the perspective view of FIG. 1D shows a panel that is curved so that X1 and X2 that are opposite sides of the rectangle are bent. Although the figure shows a case where the display surface side is curved in a concave shape, it may be convex. Thus, it is desirable that the antistatic function film 65 is formed on the side surface and the end portion located on the side to be bent. On the other hand, the antistatic functional film 65 does not necessarily have to be formed on the side surfaces and the end portions at the positions of Y1 and Y2, which are sides that are not bent during the bending.

  FIG. 2 is a cross-sectional view of the array substrate of the liquid crystal panel according to the first embodiment of the present invention, and is particularly a diagram for explaining the configuration of the pixel portion. As shown in FIG. 2, the array substrate 10 is formed by forming an amorphous silicon thin film transistor (hereinafter referred to as a-Si TFT) as a TFT (Thin Film Transistor :) element portion 9 on a glass substrate 1. . The TFT element portion 9 includes a gate electrode 2, a gate insulating film 3, a non-doped amorphous silicon layer 4, an N-type amorphous silicon layer 5, a source / drain electrode 6, an interlayer insulating film 7, ITO (Indium Tin Oxide). The electrode 8 is configured. The thickness of the glass substrate 1 is 0.7 mm, for example.

Note that silicon nitride (SiN film) or silicon oxide is interposed between the glass substrate 1 and the gate electrode 2 so that impurities do not diffuse from the glass substrate 1 to the non-doped amorphous silicon layer 4 and the N-type amorphous silicon layer 5. A film (SiO ₂ film) or a composite film thereof may be provided. The glass substrate 1 may be transparent and insulating, and a low alkali glass substrate or a quartz substrate is used.

  The TFT element portion 9 is manufactured by a known method, and a polysilicon TFT or a microcrystalline silicon TFT may be used instead of the a-Si TFT. The liquid crystal mode may be, for example, STN (Super Twisted Nematic), TN (Twisted Nematic), ECB (Electrically Controlled Birefringence), OCB (Optical Compensated Birefringence, etc.). Further, the display method of the liquid crystal display device is not particularly limited, such as a transmissive type, a reflective type, and a transflective type.

  FIG. 3 is a perspective view of the array substrate 10 and the counter substrate 20 according to the first embodiment of the present invention. In FIG. 3, for example, a case where four liquid crystal panels are manufactured from a pair of array substrate 10 and counter substrate 20 is illustrated. As shown in FIG. 3, a sealing material 12 is formed on the array substrate 10, and the sealing material 12 is formed in a frame shape so as to surround a region where liquid crystal is injected and a liquid crystal is injected. A peripheral sealing 31 is applied and formed along the periphery of the array substrate 10. The two substrates are aligned and bonded so that the pixel display portion 23 of the counter substrate 20 enters the frame of the sealing material 12 of the array substrate 10 and overlaps the pixel display portion (not shown) of the array substrate 10.

  4 and 5 show a method for manufacturing a liquid crystal panel, and are cross-sectional views taken along line AA of FIG. As shown in FIG. 4, an alignment film 11 is formed by transfer printing so as to cover at least the pixel display portion (not shown) on the upper surface of the TFT element portion 9. In Embodiment 1, it is formed using soluble polyimide, but it may be formed using various alignment film materials such as known polyamic acid. The alignment film 11 is subjected to a known rubbing treatment to give a force for aligning the liquid crystal and then washed. After the cleaning, as shown in FIG. 5, for example, a sealing material 12 mixed with a glass fiber having a diameter of 3.9 μm is formed in a frame shape by opening the liquid crystal injection port. In the first embodiment, the sealing material 12 is bonded by a dispenser using an epoxy adhesive, but various adhesives such as a thermosetting type and a light (UV) type can be used.

  6 and 7 show a method for manufacturing a liquid crystal panel, and are cross-sectional views taken along the line BB of FIG. As shown in FIG. 6, the counter substrate 20 has a color filter 22 and a black matrix (not shown) formed on the upper surface of a glass substrate 21 so as to cover a pixel display portion (not shown). The color filter 22 is made of acrylic resin, for example, and the thickness of the glass substrate 21 is 0.7 mm, for example. In order to smooth the unevenness of the color filter 22 and the black matrix, an organic film or an inorganic film called an overcoat film (not shown) may be formed on the upper surfaces of the color filter 22 and the black matrix.

  After the color filter 22 is formed, an alignment film (not shown) is formed on the counter substrate 20 by a transfer printing method. Next, the alignment film is subjected to a known rubbing process to impart a force for aligning the liquid crystal, and then washed, so that the density of the spacers 25 defining the interval for filling the liquid crystal becomes uniform as shown in FIG. Spread like so. The spacer 25 is a black sphere having a diameter of 5 μm made of, for example, a silicon oxide film (SiO 2). In the first embodiment, the filling interval of the liquid crystal is defined by the spacer 25. However, the filling interval of the liquid crystal is defined by providing a columnar, bowl-like, or lattice-like structure on the black matrix of the counter substrate 20 with an organic film or the like. There is no limitation on the method for defining the filling interval and the manufacturing method.

  8 to 11 are cross-sectional views of the bonded substrate board 30, which are a method for manufacturing a liquid crystal panel according to Embodiment 1 of the present invention. As shown in FIG. 8, the pixel display unit 23 (FIG. 3) of the counter substrate 20 and the pixel display unit (not shown) in the frame of the sealing material 12 of the array substrate 10 are aligned and bonded together. Then, the bonded substrate 30 is formed. For the bonding, the array substrate 10 and the counter substrate 20 are bonded to each other by pressurizing them with a predetermined pressure in a direction approaching each other and heat-curing the sealing material 12.

  After the formation of the bonded substrate 30, the peripheral sealing 31 is formed along the periphery of the bonded substrate 30, as shown in FIG. The peripheral sealing 31 is formed by immersing a UV curable resin into the bonded substrate 30 and then curing it by irradiating with UV light. By forming the peripheral sealing 31, it is possible to prevent the etching liquid from entering the bonded substrate 30 when the glass substrates 1 and 21 are thinned by etching. In the first embodiment, the UV curable resin is used as the material of the peripheral sealing 31, but it is only necessary to prevent the etching liquid from entering the bonded substrate 30 with a material that does not dissolve in the etching liquid. The material and forming method of the stopper 31 are not particularly limited. Moreover, the formation position and width | variety of the periphery sealing 31 should just be located in the outer peripheral side rather than the sealing material 12 on the array board | substrate 10, and it formed with the width | variety of 5-10 mm in this Embodiment 1. FIG.

  After the formation of the peripheral sealing 31, as shown in FIG. 10, the glass substrates 1 and 21 of the bonded substrate 30 are etched with a solution containing hydrofluoric acid (HF) after the peripheral sealing 31 is formed. The bonded substrate 40 is formed by adjusting the etching time and the solution so that the thicknesses 21 and 21 are each 0.2 mm. In Embodiment 1 of the present invention, the glass substrates 1 and 21 are thinned by an etching method using a solution containing HF. However, for example, a polishing method using cerium oxide or the like may be used. A polishing method may be combined, and the method is not particularly limited. Moreover, you may change arbitrarily the thickness of the glass substrates 1 and 21 according to a use.

After reducing the thickness of the glass substrates 1 and 21, the bonded substrate 40 is cut into panels 50 by cutting as shown in FIG. 12 is a front view of the bonded substrate 40 at the time of cutting according to Embodiment 1 of the present invention, and FIG. 13 is a cross-sectional view of the bonded substrate 40 at the time of cutting according to Embodiment 1 of the present invention. As shown in FIGS. 12 and 12, on the glass substrate 21 of the bonded substrate 40, a ruled line 60 and a vertical crack 61 are formed at predetermined positions using a general scribe wheel for cutting. Yes. Thereafter, the panel 50 is divided along the ruled lines 60 by a manual operation or a break device. At this time, the four sides of the glass substrates 1 and 21 are cut to the same size, and are divided so that the terminals 13 connected to the ACF (Anisotropic Conductive Film) provided on the glass substrate 1 are not exposed. did.

  FIG. 14 is a cross-sectional view of the panel 50 after the liquid crystal 51 is injected into the divided panel 50. In order to inject the liquid crystal 51, first, the cut panel 50 and the liquid crystal 51 are placed in a vacuum chamber, and the inside of the chamber is evacuated to remove air inside the panel 50. At this time, so-called slow exhaust is performed to slow down the vacuuming speed, thereby preventing the glass substrates 1 and 21 from being deformed due to the pressure inside the panel 50 being relatively higher than the pressure inside the chamber. . After removing the air inside the panel 50, the liquid crystal 51 is injected from the liquid crystal inlet by bringing the liquid crystal inlet (not shown) of the panel 50 into contact with the liquid crystal 51 and then returning to the atmospheric pressure in the vacuum chamber. . After the liquid crystal 51 is injected, the liquid crystal injection port is closed using an injection port sealing material (not shown) which is an ultraviolet curable adhesive. Note that the liquid crystal injection port only needs to be disposed on the side of the panel 50 where the terminal 13 is not provided, and the numerical aperture, size, and arrangement position are not particularly limited.

  FIG. 15 is a cross-sectional view of a scribe line 60 and a vertical crack 61 formed by a scribe wheel when the bonded substrate 40 is divided into panels 50. As shown in FIG. 15, in addition to the ruled lines 60 and the vertical cracks 61, microcracks 62 are generated. The microcracks 62 are often generated starting from the scribe lines 60 and the vertical cracks 61. The microcracks 62 have a size of about several μm and the direction in which they occur is not uniform. Such ruled lines 60, vertical cracks 61, and microcracks 62 are factors that determine the bending strength of the panel 50, and measures for the microcracks 62 are particularly necessary. This is because the shape of the scribe line 60 and the depth of penetration of the vertical crack 61 in the depth direction can be made uniform by adjusting the process conditions and selecting the type of scribe wheel. Although it is a technique, it is difficult to control the microcrack 62.

  Therefore, with respect to the ruled lines 60 and the vertical cracks 61, it is possible to suppress the influence on the bending strength of the liquid crystal panel by a constant control. However, the microcracks 62 are formed in all directions without control, and are changed over time. Since it is extended or newly generated by the load, it is one of the major factors that lower the bending strength of the panel 50.

  On the other hand, since the IPS liquid crystal panel does not have an electrode on the counter substrate, it is necessary to add an antistatic function to compensate for electrostatic resistance. As a method of adding an antistatic function, a method of applying and forming on the glass substrate 21 of the counter substrate 20 of the panel 50 by a wet process using a paint containing silica and containing transparent and conductive fine particles is conceivable. The coating material may be one in which highly conductive particles such as very fine metal particles or carbon nanofibers are dispersed instead of transparent conductive fine particles.

  From the above, in the first embodiment, the improvement of the bending strength of the liquid crystal panel and the antistatic function are simultaneously added with the minimum number of steps. That is, in the first embodiment, in a flexible liquid crystal panel formed by bonding two glass substrates, at least one of the outer main surface of the glass substrate and the end and side surfaces of the glass substrate. It is characterized by applying a paint having transparent conductivity. In addition, you may apply | coat a coating material to the glass edge part and side surface of 4 sides of a glass substrate. In particular, in the case of a curved panel in which two opposite sides of the liquid crystal panel, for example, the upper and lower sides or the left and right sides are bent, the paint is applied to the end and side surfaces of the substrate for the two bent sides. Like that. In addition, in the case of such a cylindrical curve, the other two sides that are not bent may not necessarily be coated with paint. Moreover, since the transparent conductive film which is an antistatic functional film to be formed has silica as a main component, its characteristics are similar to those of a glass substrate having silica as a main component and it has excellent adhesion. Therefore, even when the glass substrate is bent, it is hardly peeled off. If there is a chip or the like at the edge of the glass substrate, if it is bent, the substrate tends to crack, but the crack is prevented by the transparent conductive film made of such a material. it can. That is, the bending strength of the substrate can be improved.

  FIG. 16 is a front view (a) and a sectional view (b) of the liquid crystal panel according to Embodiment 1 of the present invention. As shown in FIG. 16, a coating material containing silica and ITO fine particles is applied to the outer main surface of the glass substrate 21 of the counter substrate 20 by a spin coating method, and then baked at 150 ° C. The antistatic functional film 65 thus formed has a surface resistance value of 3.5E + 06, a wavelength of 400 to 800 nm and a transmittance of 85% or more, and satisfies the film characteristics necessary for antistatic of the IPS liquid crystal panel. ing. The surface resistance value was measured using Hiresta (registered trademark) manufactured by Mitsubishi Chemical, and the spectral transmittance was measured using a spectral transmittance measuring device manufactured by Shimadzu Corporation. Other measurement devices may be used as long as the measurement can be performed.

  By the coating treatment by spin coating, the coating material wraps around the glass end portions and the side surfaces 64 of the glass substrates 1 and 21 of the liquid crystal panel, and the ruled line traces formed at the glass end portions and the side surfaces 64 of the glass substrates 1 and 21. Penetration so as to embed 63 and microcracks 62. In addition, water and a solvent are mix | blended with the coating material, for example, a viscosity is 1-10 mPa.s. It mix | blends so that it may become the range of s. The silica contained in the paint that has wrapped around the glass edges and side surfaces 64 of the glass substrates 1 and 21 is cured by heat treatment such as laser light irradiation after the hydrolysis or polycondensation proceeds to form a silica sol. Vitrify. In the first embodiment, the laser light irradiation intensity and irradiation time are adjusted, and the laser light is locally irradiated only on the glass end portions and the side surfaces 64 of the glass substrates 1 and 21 on which the paint is vitrified. The portion irradiated with the laser light may be about 300 ° C. which is a temperature at which silica is vitrified. However, it is important to irradiate locally the members constituting the panel 50 so as not to be damaged by high temperature overheating. Become. Thereafter, the glass substrate 21 is cut along a cutting line 66 shown in FIG.

  FIG. 17 is a cross-sectional view of a liquid crystal panel on which an antistatic functional film 65 is formed. By coating the entire outer main surface of the glass substrate 21, the glass end portions and the side surfaces 64 of the glass substrates 1 and 21, and locally irradiating the glass end portions and the side surfaces 64 of the glass substrates 1 and 21 with laser light. Further, the antistatic functional film 65 is formed on the entire outer main surface of the glass substrate 21 of the counter substrate 20, and the glass end portions and the side surfaces 64 of the glass substrates 1 and 21 are strengthened to improve the bending strength. Was made. In the first embodiment, the laser light irradiation area has a width of 1 mm from the end of the liquid crystal panel. However, the laser light irradiation area is not particularly limited as long as it does not affect the display area and the constituent members of the liquid crystal panel.

  In the first embodiment, the antistatic functional film 65 is formed using a paint containing ITO fine particles, but any material that is transparent and conductive and functionally satisfactory in the use of a liquid crystal panel may be used. For example, a solution containing known zinc oxide, tin oxide, tin oxide doped with antimony, or the like may be used. Further, in the first embodiment of the present invention, the baking temperature of the paint is 150 ° C., and the glass end portions and the side surfaces 64 of the glass substrates 1 and 21 are cured and vitrified at 300 ° C., but this affects the liquid crystal panel. It is sufficient that the temperature is within a range, and a temperature as high as possible that does not affect the liquid crystal panel is preferable from the viewpoint of glass strengthening because polycondensation of the paint progresses and a stronger film can be obtained.

  In the first embodiment, the heat treatment with laser light is performed to cure the paint applied to the glass substrates 1 and 21, but there is no particular limitation on the type of laser light, the irradiation method, and the irradiation conditions. As long as the heating temperature for curing the silica can be obtained, irradiation with halogen light, infrared light, or the like, or a heating method may be used other than laser light. Silica is more preferable as long as it has a viscosity that allows it to easily penetrate into the microcracks 62, but the thickness to be formed is not particularly specified, and the unevenness and gaps of the microcracks 62, the ruled line traces 63, or both may be filled. Any thickness is possible. In the first embodiment, the coating method is applied by spin coating. However, a known coating material or solution such as a dispensing method, a spray coating method, a dip method, a printing method, a slit coating method, or an ink jet printing method is used. The coating forming method may be applied, and the coating method is not limited.

  FIG. 18 is a cross-sectional view of the liquid crystal panel 54 when the polarizing plate 52 according to Embodiment 1 of the present invention is formed. As shown in FIG. 18, a liquid crystal panel 54 is manufactured by attaching polarizing plates 52 to both surfaces of the reinforced liquid crystal panel 53 of FIG. 17. As the polarizing plate 52, for example, a film in which iodine is adsorbed on a polymer film is used.

  FIG. 19 is an external explanatory view of the liquid crystal panel 54 according to Embodiment 1 of the present invention. As shown in FIG. 19, the liquid crystal panel 54 is curved at two curvatures facing each other where the terminal 13 does not exist with a predetermined curvature, and although not shown, a backlight, an ACF, a PCB (Printed Circuit Board), and a TAB (Tape). The display device is completed by mounting Automated Bonding) or the like.

  In the first embodiment, PCB and TAB are mounted after being bent, but may be manufactured by any known use and any process. Also, the process of applying and curing the coating material may be performed after being divided into a single panel 50, and may be before or after the liquid crystal panel 54 is bent or before or after the PCB or TAB is mounted. Further, the curvature and the bending method for bending the liquid crystal panel 54 are not particularly limited, and the liquid crystal panel 54 may be bent in any direction including a convex surface or a concave surface, or a combination of the concave surface and the convex surface. At this time, two opposing sides of the liquid crystal panel 54 to be curved are two opposing sides other than the side where the terminals 13 formed on the array substrate 10 are provided. That is, since the microcrack 62 and the ruled line trace 63 generated when the glass substrate 21 of the counter substrate 20 is cut to expose the terminal 13 are not strengthened, stress is applied to the side where the terminal 13 is provided. Do not bend so as not to add.

  Next, it is confirmed that the bending strength of the glass substrate, which is a feature of the present invention, is improved by measuring the breaking strength of the manufactured liquid crystal panel. For the measurement of bending strength, a four-point bending test based on JIS-R1601 is generally used. However, when a four-point bending test is performed on a liquid crystal panel, the sealing material 12 formed on the substrate, the polarizing plate 52, and the like are affected. Because of the combined fracture strength including these, it is difficult to accurately grasp the effects of the present invention. Therefore, in the four-point bending test according to the first embodiment, after using the test substrate 70 having a thickness of 0.2 mm divided by the scribe wheel similarly to the liquid crystal panel and applying the paint along the ruled lines 60 by the above-described method. What was hardened was made into the fracture strength evaluation sample.

  FIG. 20 is a cross-sectional view of a sample when performing a four-point bending test according to Embodiment 1 of the present invention. As shown in FIG. 20, the breaking strength applied to the sample by performing the four-point bending test is such that the portion to be broken does not contact the supporting point, and a bending stress is uniformly applied between the two supporting points. Therefore, it is possible to accurately evaluate the bending fracture strength of the liquid crystal panel including the influence of the bending strength of the liquid crystal panel due to the ruled lines 60 and the microcracks 62.

  Hereinafter, the evaluation of the strength and defect rate of the test substrate 70 using the four-point bending test method will be described. FIG. 21 is a front view and a cross-sectional view of a test sample according to Embodiment 1 of the present invention. As shown in FIG. 21A, a test 1-1 is performed with a glass substrate a in a state where no paint is applied to the test substrate 70, and the result of the test 1-1 is used as a reference for evaluation. On the other hand, as shown in FIG. 21 (b), only the one main surface of the test substrate 70 to be curved in the four-point bending test and the glass end portions and the side surfaces of the two sides facing each other in order to obtain the same state as the actual liquid crystal panel. Test 1-2 with a glass substrate b having an antistatic function film 65 formed by applying a coating material to is performed. Regarding the formation of the antistatic functional film 65 on the glass substrate b, masking was performed with a tape so that the coating was not applied to two opposing sides that were not curved, and the coating was applied by spin coating. By comparing the evaluation results of Test 1-1 and Test 1-2, the influence on the breaking strength by applying the paint is examined.

  In addition, each test increased the parameter by repeating this test twice using 30 test boards 70, and raised the reliability of data. Further, the glass substrate 70 is coated with the above-described paint in a flat state without being bent, and the silica sol is vitrified by irradiation with laser light.

  In the four-point bending test shown in FIG. 20, L1 is the distance between the lower fulcrums, L2 is the distance between the upper fulcrums, W is the width of the liquid crystal panel, T is the thickness of the liquid crystal panel, and F is the test force. Thus, the stress σ was obtained. In the first embodiment, a static material tester EZGraph (registered trademark) manufactured by Shimadzu Corporation is used for measuring the test force, and fixed at L1 = 40 mm, L2 = 15 mm, and W = 50 mm, respectively. The value measured with a micrometer was used.

  Table 1 shows the measurement results of Test 1-1 and Test 1-2. As shown in Table 1, the bending fracture stress in Test 1-1 was 151 for the first average stress and about 32 for the standard deviation, and about 32 for the second average stress of 173 MPa and about 28 for the standard deviation. On the other hand, regarding the bending fracture stress in Test 1-2, the first average stress was 180 MPa and the standard deviation was about 12, and the second average stress was 168 MPa and the standard deviation was about 14.

  From the above results, the bending fracture stress was slightly higher in the test 1-2, but the standard deviation was greatly different, and the test 1-2 was more varied than the test 1-1. The ratio of becoming small and poor became low. Therefore, it was confirmed that the defective rate can be reduced by applying the coating material to form the antistatic functional film 65. Note that the failure mode of the liquid crystal panel according to the four-point bending test of the first embodiment is different from the support point, and is all failure from the liquid crystal panel end and the side surface 64, and the failure due to a specific problem at the support point. I am sure it is not.

  From the above, the paint is applied to the upper surface of the glass substrate 21 of the counter substrate 20 and the end portions and the side surfaces 64 of the glass substrates 1 and 21, and the laser beam is locally applied to the end portions and the side surfaces 64 of the glass substrates 1, 21. Is cured and vitrified to add an antistatic function to the liquid crystal panel and improve the bending strength.

<Embodiment 2>
In the second embodiment, a resistance heating pattern (thin film pattern) 71 for performing resistance heating is formed in advance along the ends of the glass substrates 1 and 21 and the side surface 64, and the resistance heating pattern 71 is subjected to heat treatment. It is characterized by curing the paint. In the second embodiment, as in the first embodiment, the bending fracture stress was measured using the four-point bending test method. FIG. 22 is a front view of a test sample according to Embodiment 2 of the present invention. As shown in FIG. 22, for example, when a resistance heating pattern 71 made of an ITO film for performing resistance heating in advance when forming the ITO electrode 8 is provided on only two sides to be bent in a four-point bending test, A heat treatment with the resistance heating pattern 71 is performed. Other coating application methods and test methods are the same as those in the first embodiment.

In the four-point bending test, the two opposite sides that curve the test substrate 70 correspond to the two opposite sides that are curved in the actual liquid crystal panel. In an actual liquid crystal panel, the resistance heating pattern 71 may be formed only on the array substrate 10, or may be formed only on the counter substrate 20, or may be formed on both the array substrate 10 and the counter substrate 20. Good. Further, the resistance heating pattern 71 may be formed on the four sides of the array substrate 10 and / or the counter substrate 20, and the thin film material to be formed, the shape of the pattern, and the size are not particularly limited as long as the resistance heating can be performed.

  The measurement results of Test 2 are shown in Table 1. As shown in Table 1, the bending fracture stress of Test 2 was 162 MPa with a first average stress of about 15 and a standard deviation of about 15 for a second average stress of 170 MPa with a standard deviation of about 7.

  From the above results, when the result of Test 2 is compared with Test 1-1, which is the standard of this test, the bending fracture stress is almost the same, but the standard deviation is greatly different. The variation was smaller than −1 and the rate of failure was low. Therefore, even in the method of heating and curing the silica gel applied by the resistance heating pattern 71 formed in advance, it is possible to reduce the defect rate as in the first embodiment using laser light for the heat treatment. confirmed. Note that the failure mode of the liquid crystal panel according to the four-point bending test of the second embodiment is different from the support point, and is all the failure from the liquid crystal panel end and the side surface 64, and the failure due to a specific problem at the support point. I am sure it is not.

  As described above, in the second embodiment, since a complicated apparatus is not used for laser light or halogen light irradiation as in the first embodiment, the liquid crystal panel is prevented from being charged without greatly increasing the number of processes. A function can be added and bending strength can be improved.

It is a figure explaining the structure of the liquid crystal panel by Embodiment 1 of this invention. It is sectional drawing of the array board | substrate of the liquid crystal panel by Embodiment 1 of this invention. It is a perspective view of the array substrate and counter substrate by Embodiment 1 of this invention. It is sectional drawing which shows the manufacturing method of the liquid crystal panel by Embodiment 1 of this invention. It is sectional drawing which shows the manufacturing method of the liquid crystal panel by Embodiment 1 of this invention. It is sectional drawing which shows the manufacturing method of the liquid crystal panel by Embodiment 1 of this invention. It is sectional drawing which shows the manufacturing method of the liquid crystal panel by Embodiment 1 of this invention. It is sectional drawing which shows the manufacturing method of the liquid crystal panel by Embodiment 1 of this invention. It is sectional drawing which shows the manufacturing method of the liquid crystal panel by Embodiment 1 of this invention. It is sectional drawing which shows the manufacturing method of the liquid crystal panel by Embodiment 1 of this invention. It is sectional drawing which shows the manufacturing method of the liquid crystal panel by Embodiment 1 of this invention. It is a front view of the bonded substrate board at the time of cutting by Embodiment 1 of the present invention. It is sectional drawing of the bonding board | substrate at the time of the cutting | disconnection by Embodiment 1 of this invention. It is sectional drawing of the liquid crystal panel by Embodiment 1 of this invention. It is a ruled line fragmentary sectional view in the bonded substrate by Embodiment 1 of the present invention. It is the front view and sectional drawing of a liquid crystal panel by Embodiment 1 of this invention. It is sectional drawing of the liquid crystal panel by Embodiment 1 of this invention. It is sectional drawing of the liquid crystal panel by Embodiment 1 of this invention. It is an external appearance explanatory drawing of the liquid crystal panel by Embodiment 1 of this invention. It is sectional drawing of a liquid crystal panel when performing the 4-point bending test by Embodiment 1 of this invention. It is the front view and sectional drawing of a test sample by Embodiment 1 of this invention. It is a front view of the test sample by Embodiment 2 of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Glass substrate, 2 Gate electrode, 3 Gate insulating film, 4 Non-dope amorphous silicon layer, 5 N type amorphous silicon layer, 6 Source drain electrode, 7 Interlayer insulating film, 8 ITO electrode, 9 TFT element part, 10 Array substrate, 11 Orientation plate, 12 Sealing material, 13 Terminal, 20 Counter substrate, 21 Glass substrate, 22 Color filter, 23 Pixel display part, 25 Spacer, 30 Bonded substrate, 31 Peripheral sealing, 40 Bonded substrate, 50 Panel, 51 liquid crystal, 52 polarizing plate, 53 reinforced panel, 54 liquid crystal panel, 60 crease line, 61 vertical crack, 62 micro crack, 63 crease line trace, 64 liquid crystal panel end and side, 65 antistatic function film, 66 cutting line, 70 test substrate, 71 resistance heating pattern.

Claims (6)

In a liquid crystal panel having flexibility formed by bonding two glass substrates,
A liquid crystal panel comprising a transparent conductive film on at least one of the outer main surface of the glass substrate and the end and side surfaces of the glass substrate. In a liquid crystal panel in which two bonded glass substrates are curved,
A liquid crystal panel comprising: a transparent conductive film that covers an outer main surface of at least one glass substrate, a bent side surface of the glass substrate, and an end portion of the side surface.   3. The liquid crystal panel according to claim 1, further comprising a thin film pattern formed along the glass end portion and the side surface for performing resistance heating. 4.   The liquid crystal panel according to any one of claims 1 to 3, wherein the transparent conductive film contains silica and conductive particles as main components. In the manufacturing method of a liquid crystal panel having flexibility formed by bonding two glass substrates,
(A) applying a transparent conductive coating to at least one of the outer principal surface of the glass substrate and the end and side surfaces of the glass substrate;
(B) firing the paint applied in the step (a);
(C) After the step (b), a step of curing the paint by irradiating light to the glass edge and side surfaces and heat-treating;
A method for producing a liquid crystal panel, comprising:   The step (c) is characterized in that a thin film pattern for resistance heating is formed in advance along the glass edge and side surfaces, and the paint is cured by heat treatment of the thin film pattern. 6. A method for producing a liquid crystal panel according to 5.

Images