JP2013205482A - Color filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a color filter formed on a film substrate made from plastic or the like and having excellent transparency and gas barrier properties.SOLUTION: A color filter 100 includes at least a pigmented layer 104, a gas barrier layer 102, and a transparent inorganic layer 101 on a film substrate 105. The multiple layers are arranged in the order of the pigmented layer 104, the gas barrier layer 102, and the transparent inorganic layer 101 from the film substrate 105. The transparent inorganic layer 101 has compression stress higher than that of the gas barrier layer 102.

Description

  The present invention relates to a so-called color filter in which a colored layer pattern or the like is formed on a film substrate such as plastic.

  Currently, liquid crystal display devices, organic EL display devices, electrophoretic display devices filled with a dispersion medium solution and charged electrophoretic particles, such as televisions, mobile phones, multifunctional mobile terminals, electronic book readers, electronic signage, etc. The use is expected to expand further in the future.

  In the full color display of the various display devices (devices) described above, a glass substrate having a thickness of about several hundred μm is used for one or both of the driving electrode and the color filter. In recent years, research for replacing a glass substrate with a film and commercializing it as a flexible display has been actively conducted. Specifically, by replacing the support of the display device from glass to film, compared to the case of using glass, the weight and toughness, thickness reduction, and roll-to-roll processing are unprecedented. (For example, Patent Document 1).

On the other hand, in general, many films are significantly inferior to glass in heat resistance, stretchability, and gas barrier properties as compared with glass, and thus may adversely affect color filter production. For example, when the gas barrier property is inferior to glass, water vapor permeates a so-called display layer such as a liquid crystal layer, a light emitting layer, or an electrophoretic particle layer, or a drive electrode, and the performance of the display device (device) is significantly deteriorated. is there. This problem has been solved by providing a gas barrier layer on the film. When a film is used as the substrate of the above-described display device, it is said that a water vapor transmission rate of about 10 ⁻² to 10 ⁻⁶ g / m ² / day is generally required, although it varies depending on the display device.

By the way, when using a film on the side where a display device (device) is visually recognized, such as when used as a substrate for a color filter, the film is required to be transparent so as not to significantly impair its optical properties. In the alkali-free glass substrate that has been used in the past, this is not a problem, but when the glass substrate is replaced with a film and a gas barrier layer is provided as described above, transparency is impaired due to these coloring. There is a possibility. Specifically, the smaller the water vapor transmission rate required to be 10 ⁻² to 10 ⁻⁶ g / m ² / day, in general, the greater the thickness of the gas barrier layer or the lamination of multiple layers. Therefore, it becomes difficult to suppress the coloring, which leads to a loss of color tone of the color filter and each display device (optical loss).

  In addition, it is possible to provide a water vapor barrier function by attaching a gas barrier film in which a gas barrier layer is formed on a transparent film to the color filter substrate via an adhesive. However, a display image of a display device (device) is formed. Since the number of members through which the transmitted light is further increased, the optical loss is increased even by this method.

JP 2010-282213 A

  The present invention has been made in view of the above problems, and a main object of the present invention is to provide a color filter formed on a film substrate such as plastic and having excellent transparency and gas barrier properties.

  In order to achieve the above object, the present invention employs the following configuration.

  The color filter of the first aspect includes a plurality of layers of at least a colored layer, a gas barrier layer, and a transparent inorganic layer on a film substrate. The plurality of layers are provided in the order of a colored layer, a gas barrier layer, and a transparent inorganic layer from the film substrate side, and the transparent inorganic layer has a larger compressive stress than the gas barrier layer.

  A second aspect is characterized in that, in the first aspect, a planarization layer is further provided on the colored layer, and the gas barrier layer is provided on the planarization layer.

  A third aspect is characterized in that, in the first aspect or the second aspect, the gas barrier layer is transparent.

  A fourth aspect is characterized in that, in any one of the first to third aspects, the transparent inorganic layer is provided immediately above the gas barrier layer.

  According to a fifth aspect, in any one of the first to fourth aspects, the transparent inorganic layer has conductivity.

  According to the first aspect, the colored layer, the gas barrier layer, and the transparent inorganic layer are provided in the order of the colored layer, the gas barrier layer, and the transparent inorganic layer from the substrate side, so that the gas barrier is closer to the display layer and the drive electrode. It becomes a structure in which a layer exists. Accordingly, it is possible to efficiently prevent water vapor from entering the display layer and the drive electrode, and it is possible to more stably protect the display device (for example, a liquid crystal display). Furthermore, since the transparent inorganic layer has a compressive stress, it is possible to reduce fine cracks existing in the gas barrier layer when the gas barrier layer is formed, and to obtain high gas barrier properties.

  According to the second aspect, the planarity is improved by providing the planarization layer on the colored layer, and the gas barrier layer is provided on the planarization layer, so that excellent gas barrier properties can be obtained. It becomes.

  According to the third aspect, since the gas barrier layer is transparent, it becomes possible to impart gas barrier properties without impairing the color of the color filter.

  According to the fourth aspect, since the transparent inorganic layer is provided immediately above the gas barrier layer, the compressive stress of the transparent inorganic layer directly acts on the gas barrier layer. This makes it possible to reduce the fine cracks existing in the gas barrier layer when forming the gas barrier layer, and to obtain higher gas barrier properties.

  According to the fifth aspect, since the transparent inorganic layer has conductivity, it is possible to add a function as a common electrode in addition to the effects described above.

  As described above, according to the present invention, a color filter formed on a film substrate such as plastic and having excellent transparency and gas barrier properties can be provided.

Cross-sectional schematic diagram showing an example of the color filter 100 Schematic diagram showing an example of the printing apparatus 200

  Hereinafter, a color filter 100 according to an embodiment of the present invention will be described with reference to the drawings. Note that “transparent” described in the following description indicates that the transmittance is 70% or more within a wavelength region of 400 nm to 800 nm which is visible light.

  FIG. 1 is a schematic cross-sectional view of the color filter 100. As shown in FIG. 1, the color filter 100 is provided with a film substrate 105, a colored layer 104, a planarization layer 103, a gas barrier layer 102, and a transparent inorganic layer 101.

A known substrate can be used as the film substrate 105. Specifically, plastic films such as polyethylene terephthalate, polyethylene naphthalate, polyether sulfone, cycloolefin polymer, polyimide, polyamide, polycarbonate, methacrylic resin, polymethyl methacrylate, polyvinyl chloride, triacetyl cellulose, epoxy resin, It is possible to use a composite material of a glass or other inorganic material and a plastic material typified by the above plastics, etc., but flexibility, weather resistance, heat resistance and solvent resistance in the manufacturing process -It may be appropriately selected and used in consideration of manufacturing costs and the like.

  A colored layer 104 is provided on the upper layer of the film substrate 105. The colored layer 104 is made of red (R), green (G), blue (B), black (Bk), white (W), cyan (C), magenta (M), yellow (Y), or the like. Although it can be used, it is not limited to these. As the colored layer 104, a layer in which each color is appropriately patterned in a stripe (stripe) matrix shape having a predetermined width or a rectangular matrix shape having a predetermined size can be used.

  As a method for forming the colored layer 104, a known method can be used. For example, a photolithography method, an inkjet method, a printing method, or the like can be used.

  A planarization layer 103 is provided on the coloring layer 104. The planarization layer 103 is provided to protect the colored pattern and planarize the colored layer 104 after the colored pattern of the colored layer 104 is formed. Note that by providing the planarization layer 103, the surface roughness of the colored layer 104 is reduced and the planarity is improved, so that the gas barrier property is improved and the resistance of the conductive transparent inorganic layer 101 is reduced. Is possible.

  A known layer can be used as the planarization layer 103. For example, an acrylic resin, an epoxy resin, a urethane resin, or a copolymer thereof can be used. For these curing, light curing, heat curing or the like may be appropriately selected and used.

  A gas barrier layer 102 is provided on the planarization layer 103. The gas barrier layer 102 can be appropriately selected from silicon oxide, silicon nitride, silicon oxynitride, aluminum oxide, diamond-like carbon (DLC), an organic gas barrier film, and the like. It can be formed by phase growth method (CVD method), atomic layer deposition method (ALD method), sol-gel method, various coating methods, etc., but desired gas barrier performance, dimensional stability, refractive index, transparency In consideration of internal stress and the like, it may be appropriately selected and used.

  The gas barrier layer 102 is provided on the planarization layer 103, but each may be a single layer or two or more layers may be stacked as long as transparency is not impaired. In the case where the gas barrier layer 102 is formed by stacking, it is effective to alternately stack the inorganic and organic polymer gas barrier layers. In addition, the material, formation method, film thickness, number of layers, and the like of the gas barrier layer 102 may be the same or different on each surface. Further, as the material of the gas barrier layer 102, a hard coat agent for improving the gas barrier performance and protecting the surface may be used, or an anchor coat agent may be used for improving the adhesion of the gas barrier layer 102 to the film substrate 105. Good. The organic polymer layer can be formed by a known method, and specifically, various coating methods such as gravure coating and die coating, and flash vapor deposition can be used. When using an organic polymer layer for the gas barrier layer 102, considering the gas barrier performance and hygroscopic linear expansion coefficient of the film substrate 105 itself used, transparency, surface roughness of the front and back, transparency, refractive index, adhesion, etc. A material, a forming method, a film thickness, and the like may be appropriately selected and used.

A transparent inorganic layer 101 is provided on the gas barrier layer 102. A known material can be used for the transparent inorganic layer 101. In the case where the transparent inorganic layer 101 has the same material or conductivity as the gas barrier layer 102, ITO, IZO, IWO, ICO, ZnO, SnO ₂ or the like is deposited by vapor deposition, ion plating, sputtering, laser ablation, It is formed by appropriately selecting from plasma CVD (Chemical Vapor Deposition) method, hot wire CVD method, sol-gel method, coating method or PLD method.

  The transparent inorganic layer 101 thus formed preferably has a compressive stress. By having a compressive stress, it is possible to apply stress to the gas barrier layer 102 to block or reduce cracks generated during the formation of the gas barrier layer 102, and as a result, the gas barrier properties of the entire color filter 100 are improved. To do. In addition, since this effect is greatly exhibited when the gas barrier layer 102 and the transparent inorganic layer 101 are in contact with each other, the transparent inorganic layer 101 is preferably provided immediately above the gas barrier layer 102.

  Note that the color filter 100 is preferably provided with the planarization layer 103 because the planarity of the colored layer 104 is improved and the gas barrier property is improved. However, the color filter 100 may not include the planarization layer 103. . In this case, the gas barrier layer 102 is provided on the colored layer 104.

  The technical scope of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

  Next, the Example which manufactures the color filter 100 based on embodiment mentioned above is demonstrated. In this example, the color filter 100 was manufactured using the printing apparatus 200 shown in FIG. In addition, this invention is not restrict | limited by the following Example.

  As illustrated in FIG. 2, the printing apparatus 200 includes an ink coating unit 202, a hot plate 203, a pattern removal unit 205, and a pattern transfer unit 206. As shown in FIG. 2, an ink peelable film base material 201, a glass plate 204, and a film substrate 105 are disposed in the printing apparatus 200.

  As the ink peelable film substrate 201, a silicone release polyester film having a substrate thickness of about 100 μm: K1504 (500 mm × 200 m × 100 μmt; manufactured by Toyobo Co., Ltd.) was used.

  As the glass plate 204, a 300 mm square glass having a thickness of 0.7 mm was wet etched, and a black matrix pattern in a color filter (8 inches, 200 ppi) and a corresponding R, G, B stripe pattern were used. Each glass plate 204 is provided with alignment marks and used for alignment.

  As the film substrate 105, a 100 μm thick polyethylene naphthalate film (manufactured by Teijin DuPont Co., Ltd., Q65FA, 300 mm × 300 mm) was used.

  In providing the colored layer 104 on the film substrate 105, each color was sequentially formed using a known method described in a patent document (Japanese Patent Laid-Open No. 2008-105400).

  As the Bk ink for the colored layer 104, 20 parts of methacrylic acid, 10 parts of methyl methacrylate, 55 parts of butyl methacrylate and 15 parts of hydroxyethyl methacrylate are dissolved in 300 parts of butyl lactate, and azobisisobutylnitrile is 0.75 in a nitrogen atmosphere. The acrylic copolymer resin was obtained by adding 5 parts and reacting at 70 degreeC for 5 hours. The acrylic copolymer resin was diluted with propylene glycol monomethyl ether acetate so that the resin concentration was 10% to obtain an acrylic copolymer resin liquid. 35.0 g of carbon black and 0.9 g of a dispersant were added to 80.1 g of this acrylic copolymer resin liquid, and kneaded with three rolls to obtain a Bk colored paste. Furthermore, the Bk colored paste was adjusted with propylene glycol monomethyl ether acetate so that the pigment concentration would be 23 to 35%, and 0.5 parts by weight of Megafac F-483SF (manufactured by DIC) was added as a leveling agent to produce Bk ink. did.

  The colored ink was prepared as follows. 19.0 g of pigment and 0.9 g of dispersant were added to 80.1 g of the above acrylic copolymer resin liquid, and kneaded with three rolls to obtain red, green and blue colored pastes. Each colored paste was adjusted so that the pigment concentration was 8 to 15% at a ratio of propylene glycol monomethyl ether acetate: propylene glycol monomethyl ether = 4: 1, and MegaFuck F-484SF (manufactured by DIC) as a leveling agent. Was added to obtain R, G and B colored inks.

  Using the above material, a color filter 100 was obtained as follows.

  First, Bk ink was applied onto the ink peelable film substrate 201 by an ink coating unit 202 (die coater) so that the dry film thickness was 1.0 μm, and then an installed 40 ° C. hot plate After drying for 30 seconds on 203 and carrying until the ink peelable film base material 201 coated with Bk ink was placed on the stage of the pattern removing unit 205, it was further waited for 120 seconds.

  Next, the Bk ink coated on the ink peelable film substrate 201 is pressed against the glass plate 204 previously set in the pattern removing unit 205 with a rubber roller, and the non-image portion is removed. The transfer part 206 was conveyed so that the image pattern of Bk ink coated on the ink peelable film substrate 201 came. Furthermore, after bonding the ink peelable film base material 201 and the film substrate 105 with a rubber roller, the ink peelable film base material 201 and the film substrate 105 are peeled off, whereby the glass plate 204 is transferred to the film substrate 105. The black matrix pattern was transferred.

  Next, drying at 80 ° C. for 3 minutes was performed on the hot plate 203 to obtain a black matrix pattern in the colored layer 104.

  An R, G, B pattern was sequentially formed on the film substrate 105 on which the black matrix pattern was formed using the alignment mark in the same manner to obtain a colored layer 104.

  After obtaining the colored layer 104 on the film substrate 105 as described above, DAROCUR 1173 (Ciba Specialty Chemicals (EM-90, manufactured by Arakawa Chemical Industries, Ltd.)) adjusted to a solid content of 10 wt% is used. Co., Ltd.) was added to the colored layer 104 with a die coater and dried at 80 ° C. for 3 minutes. Then, the planarizing layer 103 was obtained on the colored layer 104 by curing with ultraviolet irradiation.

Subsequently, a silicon oxide film is formed on the planarizing layer 103 so as to have a film thickness of 50 nm by sputtering using Si as a target, using Ar as a process gas and O ₂ as a reactive gas, to form a gas barrier layer 102. Got.

Further, an ITO film is formed on the silicon oxide by using a sputtering method using ITO as a target, Ar as a process gas, and O ₂ as a reactive gas. Layer 101 was obtained.

The color filter 100 in this embodiment was obtained by the above method. The non-patterned portion of the color filter 100 had a water vapor transmission rate of 0.01 g / m ² / day and a light transmittance of 85% at 400 to 800 nm.

DESCRIPTION OF SYMBOLS 100 Color filter 101 Transparent inorganic layer 102 Gas barrier layer 103 Flattening layer 104 Colored layer 105 Film substrate 200 Printing apparatus 201 Ink peelable film base material 202 Ink coating part 203 Hotplate 204 Glass plate 205 Pattern removal part 206 Pattern transfer part

Claims (5)

A color filter having a plurality of layers of at least a colored layer, a gas barrier layer, and a transparent inorganic layer on a film substrate,
The plurality of layers are provided in the order of the colored layer, the gas barrier layer, and the transparent inorganic layer from the film substrate side,
The color filter, wherein the transparent inorganic layer has a compressive stress larger than that of the gas barrier layer. Further comprising a planarizing layer on the colored layer;
The color filter according to claim 1, wherein the gas barrier layer is provided on the planarizing layer.   The color filter according to claim 1, wherein the gas barrier layer is transparent.   The color filter according to claim 1, wherein the transparent inorganic layer is provided directly on the gas barrier layer.   The color filter according to claim 1, wherein the transparent inorganic layer has conductivity.

Images