JP2010014873A - Method for producing color filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a color filter which can produce a color filter of high quality at a low cost without damaging colored layers and an ITO layer during carrying in a production process. <P>SOLUTION: At first, a black matrix layer 12, a red layer 15, a blue layer 16 and a green layer 17 are formed on one surface 11a of a color filter substrate 11. Next, an overcoat layer 18 is formed on the black matrix layer 12, the red layer 15, the blue layer 16 and the green layer 17. Thereafter, an ITO layer 19 is formed on the other surface 11b of the color filter substrate 11 by application, thus the color filter 10 can be produced without damaging the colored layers 15, 16, 17 and the ITO layer 19. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a color filter used in a lateral electric field (IPS) type liquid crystal display device, and in particular, a colored layer and an ITO layer are not damaged during transportation in the manufacturing process, and the color is high quality and low cost. The present invention relates to a color filter manufacturing method capable of manufacturing a filter.

  Conventionally, a color liquid crystal display device has been used as a flat display. In such a liquid crystal display device, a color filter and a thin film transistor (TFT) substrate face each other with a predetermined gap, and a liquid crystal material is injected into the gap to form a liquid crystal layer.

  Such a color filter has a color filter substrate, a black matrix layer formed on the surface of the color filter substrate, and a colored layer composed of each color of red, blue, and green formed on the surface of the color filter substrate. .

  In particular, for a color filter used in a lateral electric field (IPS) liquid crystal display device, a conductive layer made of, for example, ITO or the like is formed on the back surface of the color filter substrate. Such a conductive layer is provided in order to prevent the above-described alignment of the liquid crystal layer from being disturbed by charging the back surface of the color filter substrate, thereby degrading the image quality of the liquid crystal display device. This conductive layer is generally formed by forming a conductive material on the back surface of the color filter substrate by sputtering.

In addition to this, various studies have been made on a method for printing an antistatic layer for preventing charging of the back surface of the color filter substrate and various conductive films for preventing static electricity.
Japanese Patent No. 4003842

  However, a sputtering apparatus used for forming a film by sputtering is expensive because it forms a film on a color filter substrate in a vacuum. Therefore, when a conductive material is formed on the back surface of the color filter substrate by sputtering, the manufacturing cost of the color filter becomes relatively high.

  Further, the black matrix layer and the colored layer are likely to be damaged while the color filter substrate is transported during sputtering. For this reason, it is difficult to form the conductive layer by sputtering on the back surface of the color filter substrate after the black matrix layer and the colored layer are formed on the surface of the color filter substrate. Under such circumstances, it is generally performed that a conductive layer is first formed on the back surface of the color filter substrate by sputtering, and then a black matrix layer and a colored layer are formed on the surface of the color filter substrate.

  However, in this case, a part of the conductive layer may be chipped, thereby generating particles, which may deteriorate the quality of the color filter. Further, when the black matrix layer and the colored layer are formed, the development process and the baking process are repeatedly performed, so that the conductive layer may be deteriorated depending on the type of the conductive material.

  The present invention has been made in consideration of such points, and the color layer and the ITO layer are not damaged during transportation in the production process, and it is possible to produce a color filter with high quality and low cost. An object is to provide a method for manufacturing a color filter.

  The present invention relates to a method of manufacturing a color filter used in an IPS liquid crystal display device, a step of preparing a color filter substrate, and a black matrix layer, a red layer, a blue layer, and a green layer on one surface of the color filter substrate. Forming an overcoat layer on the black matrix layer, red layer, blue layer, and green layer, and forming the black matrix layer, red layer, blue layer, green on one side of the color filter substrate And a step of forming an ITO layer on the other surface of the color filter substrate by forming the layer and the overcoat layer.

  In the present invention, when the ITO layer is formed, the color filter substrate is placed in a state in which the other surface of the color filter substrate faces downward and the end of the color filter substrate is gripped while the color filter substrate is floated from below. An ITO layer coating solution is applied from below by a surface tension type coating apparatus.

  In the present invention, when the ITO layer is formed, the color filter substrate is formed in a state in which the other surface of the color filter substrate faces upward and the end of the color filter substrate is gripped while the color filter substrate is floated from below. An ITO layer coating solution is applied from above by a coating apparatus.

  In the present invention, when forming the ITO layer, the color filter substrate is oriented in the vertical direction, and the upper end portion of the color filter substrate is suspended, and the ITO layer coating liquid is applied from the side of the color filter substrate by the coating apparatus. A method for producing a color filter characterized by the above.

  The present invention further comprises a step of baking the color filter substrate after applying the ITO layer coating solution and baking the ITO layer coating solution to form an ITO layer. Is the method.

  This invention is a manufacturing method of the color filter characterized by the ITO layer coating liquid containing ITO microparticles | fine-particles, a dispersion liquid, and a solvent.

  As described above, according to the present invention, after the black matrix layer, the red layer, the blue layer, the green layer, and the overcoat layer are formed on one surface of the color filter substrate, the ITO layer is formed on the other surface of the color filter substrate. Is formed by coating, so that a part of the ITO layer is missing and particles are generated during the transport in the process of forming the black matrix layer, the red layer, the blue layer, the green layer, and the overcoat layer, or the process before and after the process. There is nothing. Therefore, it is possible to reliably prevent the quality of the color filter from being deteriorated due to the lack of a part of the ITO layer.

  According to the present invention, when forming the ITO layer, the ITO layer coating solution is applied to the color filter substrate in a state where the color filter substrate is air levitated from below while gripping the end of the color filter substrate. . Alternatively, when forming the ITO layer, the color filter substrate is oriented in the vertical direction, and the ITO layer coating solution is applied to the color filter substrate while suspending the upper end portion of the color filter substrate. As a result, there is no possibility that the black matrix layer, the red layer, the blue layer, the green layer, and the overcoat layer that have already been formed on one surface of the color filter substrate are damaged or stained. Moreover, since the sputtering apparatus is not used when forming the ITO layer, the manufacturing cost of the color filter can be kept low.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic sectional view showing a color filter, and FIG. 2 is a schematic sectional view showing another configuration of the color filter. FIGS. 3A to 3F are process diagrams showing a method for manufacturing the color filter shown in FIG. 1, and FIGS. 4A to 4E are processes showing a method for manufacturing the color filter shown in FIG. FIG. FIG. 5 is a diagram showing a coating process of the ITO layer coating solution when the ITO layer coating solution is applied from below the color filter substrate, and FIG. 6 shows the ITO layer coating solution from above the color filter substrate. It is a figure which shows the application | coating process of the ITO layer coating liquid in the case of apply | coating. FIG. 7 is a diagram illustrating an ITO layer coating solution application process in the case where the ITO layer coating solution is applied from the side of the color filter substrate.

Configuration of Color Filter First, an outline of a color filter will be described with reference to FIGS.

  A color filter 10 shown in FIG. 1 is used in a lateral electric field (IPS) liquid crystal display device. The color filter 10 includes a color filter substrate 11, a black matrix layer 12 formed on one surface 11a of the color filter substrate 11, a red layer 15 formed on one surface 11a of the color filter substrate 11, A blue layer 16 and a green layer 17 are provided.

  In addition, a transparent overcoat layer 18 is formed on the black matrix layer 12, the red layer 15, the blue layer 16, and the green layer 17 so as to cover the black matrix layer 12, the red layer 15, the blue layer 16, and the green layer 17. Has been. Further, a plurality of spacers 20 are provided on the overcoat layer 18 at predetermined positions corresponding to the black matrix layer 12.

  On the other hand, an ITO (indium tin oxide) layer 19 is uniformly formed on the other surface 11 b of the color filter substrate 11.

  As the color filter substrate 11, quartz glass, borosilicate glass, aluminosilicate glass, inorganic glass such as soda lime glass whose surface is coated with silica, organic plastic film or sheet, and the like can be used.

  The black matrix layer 12 may be either a metal thin film such as Cr or CrOx or a thin film in which a light shielding agent is dispersed in a resin. However, for the stable display of the IPS system, the light shielding agent is dispersed. A resin black matrix is preferred. As the light-shielding agent, those containing metal oxide powder such as carbon black, titanium oxide, iron tetroxide, metal sulfide powder, metal powder and the like can be used. Among these, carbon black is particularly preferable because it has excellent light-shielding properties and can form a high-resistivity black matrix by using coated carbon.

  The resin used for the black matrix layer 12 is not particularly limited, but photosensitive or non-photosensitive materials such as epoxy resins, acrylic resins, urethane resins, polyester resins, polyimide resins, polyolefin resins, and the like. Preferably used. The black matrix resin is preferably a resin having high heat resistance, and a polyimide resin is particularly preferably used since a resin resistant to an organic solvent used in the step after the black matrix layer 12 is formed is preferable.

  The film thickness of the black matrix layer 12 is preferably 0.5 μm to 1.5 μm, more preferably 0.8 μm to 1.3 μm. When this film thickness is thinner than 0.5 μm, the light shielding property is insufficient, which is not preferable.

  On the other hand, the red layer 15, the blue layer 16, and the green layer 17 are colored layers colored in red, blue, and green, respectively, and a resin colored with a colorant is used.

  As the colorant used in the colored layer, organic pigments, inorganic pigments, dyes, and the like can be suitably used, and various additives such as ultraviolet absorbers, dispersants, and leveling agents may be added. . As the organic pigment, phthalocyanine, azirake, condensed azo, quinacridone, anthraquinone, perylene, and perinone are preferably used.

  As the resin used for the colorant, a photosensitive or non-photosensitive material such as an epoxy resin, an acrylic resin, a urethane resin, a polyester resin, a polyimide resin, or a polyolefin resin is preferably used. It is preferable to disperse or dissolve in the resin to color. Photosensitive resins include photodegradable resins, photocrosslinkable resins, and photopolymerizable resins. Particularly, monomers, oligomers, or polymers having an ethylenically unsaturated bond and initiators that generate radicals by ultraviolet rays are used. A photosensitive composition, a photosensitive polyamic acid composition, and the like are preferably used. As the non-photosensitive resin, those that can be developed with the above-mentioned various polymers are preferably used, but the heat resistance is such that it can withstand the heat applied in the transparent conductive film forming process and the liquid crystal display manufacturing process. Since a resin having a resistance to organic solvents used in the manufacturing process of a liquid crystal display device is preferable, a polyimide resin is particularly preferably used. Here, as a preferable polyimide resin, the polyimide resin preferably used as a material of the above-mentioned resin black matrix can be mentioned.

  The thickness of the red layer 15, the blue layer 16, and the green layer 17 is preferably 0.9 to 3 μm, more preferably 1.6 to 2.4 μm per layer. When the thickness of the colored layer is 0.9 μm or less, the inclination angle of the color filter surface on the pattern edge of the black matrix layer 12 becomes large, and alignment failure tends to occur. On the other hand, when the film thickness exceeds 3 μm, it becomes difficult to uniformly apply the red layer 15, the blue layer 16, and the green layer 17.

  The resin used for the overcoat layer 18 is preferably an epoxy resin, an acrylic resin, a urethane resin, a polyester resin, a polyimide resin, a polyolefin resin, gelatin, or the like. A resin having heat resistance that can withstand heat applied in the film process and the manufacturing process of the liquid crystal display device is preferable, and a resin having resistance to an organic solvent used in the manufacturing apparatus of the liquid crystal display device is preferable. Polyimide resins and acrylic resins are preferably used.

  The overcoat layer 18 is provided to flatten the surface of the color filter 10 and to prevent the components contained in the red layer 15, the blue layer 16, and the green layer 17 from eluting into the liquid crystal layer. is there. The thickness of the overcoat layer 18 can be set in consideration of the light transmittance of the material used, the surface state of the color filter 10, etc., and can be set in the range of 0.1 to 3.0 μm, for example. . Such an overcoat layer 18 is formed so as to cover at least a portion of the red layer 15, the blue layer 16, and the green layer 17 that comes into contact with the liquid crystal layer when the color filter 10 is bonded to the TFT substrate.

  Further, the spacer 20 is provided to form a gap between the color filter 10 and the TFT substrate when the color filter 10 is bonded to the TFT substrate. The spacer 20 has a certain height so as to protrude from the overcoat layer 18 in a range of about 2 μm to 10 μm. The amount of protrusion can be set as appropriate from the thickness required for the liquid crystal layer of the liquid crystal display device. In addition, the formation density of the spacers 20 can be appropriately set in consideration of the thickness unevenness of the liquid crystal layer, the aperture ratio, the shape, material, and the like of the spacers 20.

  The spacer 20 is made of a cured product containing a photosensitive resin as a main component, and this photosensitive resin may be either a positive photosensitive resin or a negative photosensitive resin. Examples of the positive photosensitive resin include a positive photosensitive resin having a styrene skeleton that generates a phenolic hydroxyl group by an acid. Moreover, as a negative photosensitive resin which can be used, for example, a negative photosensitive resin in which an epoxy is added to a copolymer of styrene and hydroxystyrene, a negative photosensitive resin in which an epoxy is added to a copolymer of styrene and carboxystyrene Etc.

  The ITO layer 19 is a layer made of indium tin oxide, and has high transparency and excellent conductivity. The thickness of the ITO layer 19 is 100 nm to 1000 nm, preferably 200 nm to 500 nm. If it is thicker than this, the transmittance will be too low, and if it is thinner than this, the conductivity will be insufficient.

  Next, another configuration of the color filter 10 will be described with reference to FIG. The color filter 10 shown in FIG. 2 is different from that shown in FIG. 1 in that the spacer 20A is formed by superimposing the colored layers (red layer 15, blue layer 16, and green layer 17). It is substantially the same as the color filter 10 shown. In FIG. 2, the same parts as those of the color filter 10 shown in FIG.

  That is, in the color filter 10 shown in FIG. 2, a plurality of spacers 20 </ b> A are provided at predetermined positions on the black matrix layer 12. Each spacer 20A has a spacer red layer 15a, a spacer blue layer 16a, a spacer green layer 17a, and a spacer overcoat layer 18a, which are the uppermost layers, sequentially formed on the black matrix layer 12. . The spacer red layer 15a, the spacer blue layer 16a, the spacer green layer 17a, and the spacer overcoat layer 18a constituting the spacer 20 are respectively the red layer 15, the blue layer 16, the green layer 17, and the overcoat layer 18a. It corresponds to the coat layer 18 and is formed simultaneously with these corresponding layers. Also, the spacer red layer 15 a, the spacer blue layer 16 a, the spacer green layer 17 a, and the spacer overcoat layer 18 a are the same as the corresponding red layer 15, blue layer 16, green layer 17, and overcoat layer 18. Consists of materials.

  In FIG. 2, the colored layer constituting the spacer 20A is laminated in order of the spacer red layer 15a, the spacer blue layer 16a, and the spacer green layer 17a from the lowermost layer side. However, the order in which the colored layers are stacked is not limited.

Manufacturing Method of Color Filter Next, a manufacturing method of the color filter 10 shown in FIG. 1 will be described with reference to FIGS.

  First, as shown in FIG. 3A, a color filter substrate 11 is prepared.

  Next, a black photosensitive material is formed on one surface 11a of the color filter substrate 11 to have a predetermined film thickness by a dipping method, a roll coater method, a spinner method, a die coating method, a method using a wire bar, or the like. Then, each process of exposure and development is performed. In this way, the black matrix layer 12 having a predetermined pattern is formed on the one surface 11a of the color filter substrate 11. (FIG. 3B).

  Next, a red layer 15, a blue layer 16, and a green layer 17 are sequentially formed on one surface 11a of the color filter substrate 11 (FIG. 3C).

  In the meantime, first, on one surface 11a of the color filter substrate 11 on which the black matrix layer 12 is formed, the coloring photosensitivity of the corresponding color is achieved by a dipping method, a roll coater method, a spinner method, a die coating method, a method using a wire bar, or the like. The material is formed so as to have a predetermined film thickness, and then exposure and development processes are performed. The red layer 15, the blue layer 16, and the green layer 17 are formed on the one surface 11 a of the color filter substrate 11 by repeating the same process for the red layer 15, the blue layer 16, and the green layer 17.

  Subsequently, an overcoat layer 18 is formed on the black matrix layer 12, the red layer 15, the blue layer 16, and the green layer 17 (FIG. 3D). At this time, first, an overcoat layer material is applied on the black matrix layer 12, the red layer 15, the blue layer 16, and the green layer 17. As a method for applying the overcoat layer material, a dipping method, a roll coater method, a spinner method, a die coating method, a method using a wire bar, and the like are preferably used as in the case of black photosensitive materials and colored photosensitive materials. Then, heat drying is performed using an oven or a hot plate. At this time, for the purpose of improving the leveling property, vacuum drying or preheating drying (semi-cure) may be performed as necessary.

  Next, a spacer 20 is formed on the overcoat layer 18 (FIG. 3E). In this case, first, a photosensitive spacer material is applied on the overcoat layer 18 by a dipping method, a roll coater method, a spinner method, a die coating method, a method using a wire bar, or the like. Next, the spacer 20 is formed on the overcoat layer 18 by exposing and developing the photosensitive spacer material using a photomask in which a pattern corresponding to the position of the spacer 20 is formed.

  Thereafter, an ITO layer 19 is formed on the other surface 11b of the color filter substrate 11 (FIG. 3E). At this time, first, the ITO layer coating liquid 19a is applied to the other surface 11b of the color filter substrate 11. The ITO layer coating liquid 19a includes ITO fine particles having a particle diameter of 1 nm to 100 nm, a dispersion for uniformly dispersing the ITO fine particles, and an organic solvent. Among these, the solvent is made of, for example, decalin, ether alcohol, or ketone solvent. Moreover, the ITO layer coating liquid 19a may contain a surfactant as necessary. The method for applying the ITO layer coating liquid 19a in this way will be described in detail below (see FIGS. 5 to 7).

  Thereafter, the color filter substrate 11 is baked (heated) at a temperature of 200 ° C. to 300 ° C., whereby the ITO layer coating liquid 19a is baked to form the ITO layer 19.

  Next, a method for manufacturing the color filter 10 shown in FIG. 2 will be described with reference to FIGS.

  First, the black matrix layer 12 having a predetermined pattern is formed on the one surface 11a of the color filter substrate 11 in the same manner as described above (FIGS. 3A to 3B). (FIGS. 4A to 4B).

  Next, a red layer 15, a blue layer 16, and a green layer 17 are sequentially formed on the color filter substrate 11 in the same manner as in the above-described step (FIG. 3C) (FIG. 4C). However, at this time, the spacer red layer 15a, the spacer blue layer 16a, and the spacer green layer 17a are formed on the black matrix layer 12 together with the corresponding red layer 15, blue layer 16, and green layer 17, respectively.

  Next, the overcoat layer 18 is formed on the black matrix layer 12, the red layer 15, the blue layer 16, the green layer 17, the spacer red layer 15a, the spacer blue layer 16a, and the spacer green layer 17a (see FIG. 3 (d)) (FIG. 4 (d)).

  Thus, the spacer 20A composed of the spacer red layer 15a, the spacer blue layer 16a, the spacer green layer 17a, and the spacer overcoat layer 18a is formed on the black matrix layer 12.

  Thereafter, an ITO layer 19 is formed on the other surface 11b of the color filter substrate 11 (FIG. 4E). At this time, in the same manner as described above, first, the ITO layer coating solution 19a is applied to the other surface 11b of the color filter substrate 11. Thereafter, the color filter substrate 11 is baked to fire the ITO layer coating liquid 19a to form the ITO layer 19. The method for applying the ITO layer coating liquid 19a will be described in detail below (see FIGS. 5 to 7).

Method of Applying ITO Layer Coating Liquid After forming the black matrix layer 12, the red layer 15, the blue layer 16, the green layer 17, and the overcoat layer 18 on one surface 11a of the color filter substrate 11, the color filter substrate A method for applying the ITO layer coating liquid 19a to the other surface 11b of the electrode 11 will be described below.

  First, referring to FIG. 5, the case where the other surface 11b of the color filter substrate 11 is directed downward and the ITO layer coating liquid 19a is applied from below the color filter substrate 11 will be described.

  A surface tension type coating apparatus 40 shown in FIG. 5 includes a coater 41 that discharges the ITO layer coating liquid 19a from below to above, an upstream surface plate 42a disposed on both sides of the coater 41, and a downstream side. A surface plate 42b and a pair of chucks 43a and 43b that horizontally hold the color filter substrate 11 and transport the color filter substrate 11 along the upper surfaces of the upstream surface plate 42a and the downstream surface plate 42b. .

  Among these, the upstream side platen 42a and the downstream side platen 42b have a large number of air blowing holes 44 on their upper surfaces. The color filter substrate 11 is levitated by the air blown out from the air blowing holes 44, and therefore the color filter substrate 11 is not bent when being conveyed by the pair of chucks 43a and 43b.

  In FIG. 5, when forming the ITO layer 19 on the other surface 11b of the color filter substrate 11, first, one surface 11a of the color filter substrate 11 is directed upward, and the other surface 11b of the color filter substrate 11 is directed downward. State. In this state, the end of the color filter substrate 11 is gripped by the pair of chucks 43a and 43b, and the color filter substrate 11 is conveyed from the upstream side platen 42a side to the downstream side platen 42b side. At this time, the color filter substrate 11 is air-lifted upward from below by the air blown from the air blowing holes 44, and a predetermined gap is provided between the color filter substrate 11 and the upstream side platen 42a and the downstream side platen 42b. It is transported in a state where a gap is left.

  During this time, the color filter substrate 11 is coated with the ITO layer coating liquid 19a from the coater 41 provided between the upstream side platen 42a and the downstream side platen 42b. That is, the coater 41 discharges and applies the ITO layer coating liquid 19a from the lower side of the color filter substrate 11 toward the other surface 11b of the color filter substrate 11. The ITO layer coating liquid 19a adheres to the other surface 11b of the color filter substrate 11 due to its surface tension.

  Next, a case where the ITO layer coating liquid 19a is applied from above the color filter substrate 11 with the other surface 11b of the color filter substrate 11 facing upward will be described with reference to FIG.

  A die coat or screen coat type coating apparatus 50 shown in FIG. 6 includes a coater 51 that discharges the ITO layer coating liquid 19a from the upper side to the lower side, and an upstream surface platen 52a disposed on both sides of the coater 51, and A downstream surface plate 52b, and a pair of chucks 53a and 53b that horizontally hold the color filter substrate 11 and convey the color filter substrate 11 along the upper surfaces of the upstream surface plate 52a and the downstream surface plate 52b. ing.

  Among these, the upstream side platen 52a and the downstream side platen 52b have a large number of air blowing holes 54 on the upper surface thereof. The color filter substrate 11 is levitated by the air blown out from the air blowing holes 54, and therefore the color filter substrate 11 does not bend when being conveyed by the pair of chucks 53a and 53b.

  In FIG. 6, when the ITO layer 19 is formed on the other surface 11b of the color filter substrate 11, first, one surface 11a of the color filter substrate 11 is directed downward, and the other surface 11b of the color filter substrate 11 is directed upward. State. In this state, the end of the color filter substrate 11 is gripped by the pair of chucks 53a and 53b, and the color filter substrate 11 is transported from the upstream surface plate 52a side to the downstream surface plate 52b side. At this time, the color filter substrate 11 is floated upward from below by the air blown from the air blowing holes 54, and a predetermined distance is provided between the color filter substrate 11 and the upstream side platen 52a and the downstream side platen 52b. It is transported in a state where a gap is left.

  In the meantime, the color filter substrate 11 is coated with the ITO layer coating liquid 19a from the coater 51 provided between the upstream side platen 52a and the downstream side platen 52b. That is, the coater 51 discharges and applies the ITO layer coating liquid 19a from above the color filter substrate 11 toward the other surface 11b of the color filter substrate 11.

  Next, the case where the color filter substrate 11 is oriented in the vertical direction and the ITO layer coating liquid 19a is applied from the side of the color filter substrate 11 will be described with reference to FIG.

  The hanging conveyance type coating apparatus 60 shown in FIG. 7 hangs the spray device 61 for applying the ITO layer coating solution 19a to the side and the upper end portion 11c of the color filter substrate 11 to hang the color filter substrate 11. And a chuck 63 that conveys the substrate while holding it vertically. Among these, the spray apparatus 61 is arrange | positioned along with the orthogonal | vertical direction, respectively, and has the some nozzle 61a which discharges the ITO layer coating liquid 19a toward each side from each front-end | tip part. The chuck 63 conveys the color filter substrate 11 in the horizontal direction and in a direction perpendicular to the coating direction of the ITO layer coating liquid 19a.

  In FIG. 7, when forming the ITO layer 19 on the other surface 11 b of the color filter substrate 11, first, the upper end portion 11 c of the color filter substrate 11 is grasped and suspended by the chuck 63, and the color filter substrate 11 is oriented vertically. The other surface 11b of the color filter substrate 11 is directed to the spray device 61 side. In this state, the chuck 63 conveys the color filter substrate 11 in a direction perpendicular to the coating direction of the ITO layer coating liquid 19a.

  During this time, the color filter substrate 11 is coated with the ITO layer coating liquid 19a from the spray device 61. That is, the spray device 61 applies the ITO layer coating liquid 19 a by discharging from the side of the color filter substrate 11 toward the other surface 11 b of the color filter substrate 11.

  As described above, according to the present embodiment, after the black matrix layer 12, the red layer 15, the blue layer 16, the green layer 17, and the overcoat layer 18 are formed on the one surface 11a of the color filter substrate 11, the color filter An ITO layer 19 is formed on the other surface 11b of the substrate 11 by coating. Therefore, a part of the ITO layer 19 is missing during the transport in the process of forming the black matrix layer 12, the red layer 15, the blue layer 16, the green layer 17, and the overcoat layer 18. It does not occur. Thereby, it is possible to reliably prevent the quality of the color filter 10 from being deteriorated due to the lack of a part of the ITO layer 19.

  Further, according to the present embodiment, when the ITO layer 19 is formed, the end portions of the color filter substrate 11 are held by the chucks 43 a and 43 b (53 a and 53 b), and the color filter substrate 11 is aired by the air from the air blowing holes 44. In a state where air is floated from below, the ITO layer coating liquid 19a is applied to the color filter substrate 11 by the coater 41 (51) (FIGS. 5 and 6). Alternatively, when forming the ITO layer 19, the color filter substrate 11 is oriented in the vertical direction, and the upper end portion 11 c of the color filter substrate 11 is suspended by the chuck 63, and the ITO layer coating liquid is applied to the color filter substrate 11 by the spray device 61. Apply (FIG. 7). Thereby, there is no possibility that the black matrix layer 12, the red layer 15, the blue layer 16, the green layer 17 and the overcoat layer 18 already formed on the one surface 11a of the color filter substrate 11 are damaged or stained. Further, since no sputtering apparatus is used when forming the ITO layer 19, the manufacturing cost of the color filter 10 can be kept low.

(Example)
Next, specific examples of the present invention will be described. First, a color filter substrate 11 made of a glass substrate is prepared, and then each layer is formed on the one surface 11a of the color filter substrate 11 in the order of a black matrix layer 12, a red layer 15, a blue layer 16, and a green layer 17 by plate making. did. Thereafter, an overcoat layer 18 was formed on the black matrix layer 12, the red layer 15, the blue layer 16, and the green layer 17. Next, an ITO layer 19 was formed on the other surface 11b of the color filter substrate 11 by coating, and thus the color filter 10 (this example) was manufactured.

  In this case, ITO dust is not generated during the plate making of the black matrix layer 12, the red layer 15, the blue layer 16, and the green layer 17, and the ITO layer 19 is not deteriorated (change in resistivity). A favorable film surface of the ITO layer 19 could be formed.

(Comparative Example 1)
Next, Comparative Example 1 of the present invention will be described. First, a color filter substrate made of a glass substrate was prepared, and an ITO layer was formed on one surface of the color filter substrate by sputtering. Next, the black matrix layer, the red layer, the blue layer, and the green layer were formed in this order on the other surface of the color filter substrate by plate making. Thereafter, an overcoat layer was formed on the black matrix layer, the red layer, the blue layer, and the green layer, and thus a color filter as Comparative Example 1 was produced.

  In this case, when forming the black matrix layer, the red layer, the blue layer, the green layer, and the overcoat layer, a part of the ITO layer formed by sputtering was lost, and ITO dust was generated.

(Comparative Example 2)
Next, Comparative Example 2 of the present invention will be described. First, a color filter substrate made of a glass substrate was prepared, and an ITO layer was formed on one surface of the color filter substrate by printing. Next, the black matrix layer, the red layer, the blue layer, and the green layer were formed in this order on the other surface of the color filter substrate by plate making. Thereafter, an overcoat layer was formed on the black matrix layer, red layer, blue layer, and green layer, and thus a color filter as Comparative Example 2 was produced.

  In this case, when the black matrix layer, the red layer, the blue layer, the green layer, and the overcoat layer were formed by plate-making, a part of the ITO layer was missing and ITO dust was generated.

FIG. 3 is a schematic cross-sectional view showing a color filter. FIG. 6 is a schematic cross-sectional view showing another configuration of a color filter. Process drawing which shows the manufacturing method of the color filter shown in FIG. Process drawing which shows the manufacturing method of the color filter shown in FIG. The figure which shows the coating process of the ITO layer coating liquid in the case of apply | coating an ITO layer coating liquid from the downward direction of a color filter board | substrate. The figure which shows the application | coating process of the ITO layer coating liquid in the case of apply | coating an ITO layer coating liquid from the upper direction of a color filter board | substrate. The figure which shows the application | coating process of the ITO layer coating liquid in the case of apply | coating an ITO layer coating liquid from the side of a color filter board | substrate.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Color filter 11 Color filter substrate 12 Black matrix layer 15 Red layer 15a Spacer red layer 16 Blue layer 16a Spacer blue layer 17 Green layer 17a Spacer green layer 18 Overcoat layer 18a Spacer overcoat layer 19 ITO layer 19a ITO Layer coating solution 20, 20A Spacer 40, 50, 60 Coating device

Claims (6)

In a method for manufacturing a color filter used in an IPS liquid crystal display device,
Preparing a color filter substrate;
Forming a black matrix layer, a red layer, a blue layer, and a green layer on one surface of the color filter substrate;
Forming an overcoat layer on the black matrix layer, the red layer, the blue layer, and the green layer;
Forming a black matrix layer, a red layer, a blue layer, a green layer, and an overcoat layer on one surface of the color filter substrate, and then forming an ITO layer on the other surface of the color filter substrate by coating. A method for producing a color filter characterized by the above.   When forming the ITO layer, with the other side of the color filter substrate facing downward and holding the edge of the color filter substrate, the color filter substrate is air-levitated from below, and the ITO layer from below the color filter substrate 2. The method for producing a color filter according to claim 1, wherein the coating liquid is applied by a surface tension type coating apparatus.   When forming the ITO layer, with the other side of the color filter substrate facing upward and holding the edge of the color filter substrate, the color filter substrate is air-levitated from below and the ITO layer from above the color filter substrate. The method for producing a color filter according to claim 1, wherein the coating liquid is applied by a coating apparatus.   When forming the ITO layer, the color filter substrate is oriented vertically, and the upper end portion of the color filter substrate is suspended, and the ITO layer coating liquid is applied from the side of the color filter substrate by a coating apparatus. The manufacturing method of the color filter of Claim 1.   5. The method according to claim 2, further comprising a step of baking the color filter substrate after applying the ITO layer coating liquid and baking the ITO layer coating liquid to form an ITO layer. A method for producing a color filter according to one item.   The method for producing a color filter according to any one of claims 2 to 5, wherein the ITO layer coating liquid contains ITO fine particles, a dispersion liquid, and a solvent.

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