JP4459682B2 - Manufacturing method of color filter - Google Patents

Description

  The present invention relates to a method for producing a color filter suitable for a color liquid crystal display in which a colored layer is formed by utilizing the difference in wettability of the surface due to the action of a photocatalyst.

  In recent years, with the development of personal computers, especially portable personal computers, the demand for liquid crystal displays, particularly color liquid crystal displays, has been increasing. However, since this color liquid crystal display is expensive, there is an increasing demand for cost reduction, and in particular, there is a high demand for cost reduction for a color filter having a high specific gravity.

  In such a color filter, it is usually provided with coloring patterns of three primary colors of red (R), green (G), and blue (B), and electrodes corresponding to the respective pixels of R, G, and B are turned on, By turning it off, the liquid crystal operates as a shutter, and light passes through each of the R, G, and B pixels, and color display is performed.

As a conventional method for producing a color filter, there is a pigment dispersion method. In this method, a photosensitive resin layer in which a pigment is dispersed is first formed on a substrate, and this is patterned to obtain a monochromatic pattern. Further, this process is repeated three times to form R, G, and B color filter layers.
Still other methods include an electrodeposition method, a method in which a pigment is dispersed in a thermosetting resin, R, G, and B are printed three times, and then the resin is thermoset. However, in any method, it is necessary to repeat the same process three times in order to color the three colors of R, G, and B, and there is a problem that the cost is high, and the yield decreases because the process is repeated There's a problem.

  Therefore, a photocatalyst-containing layer is formed on the base material using a coating solution for property change pattern formation containing a photocatalyst and a material whose properties change due to the action of the photocatalyst accompanying energy irradiation, and is exposed in a pattern. Thus, the inventors have studied a method for manufacturing a color filter that forms a pattern with changed characteristics and forms a colored layer (Patent Document 1). According to this method, it is possible to easily form a colored layer using the characteristics of the photocatalyst-containing layer.

  In such a color filter manufacturing method, the wettability of the surface is changed by the action of the photocatalyst by exposure, and the colored layer is formed by utilizing the difference in wettability. Therefore, the exposure process is an essential process. It becomes. In such an exposure process, if the time for causing the difference in wettability can be shortened, the manufacturing time can be shortened and the manufacturing efficiency can be improved.

Japanese Patent Laid-Open No. 2001-074928

  The present invention has been made in view of the above circumstances, and a main object of the present invention is to provide a method for manufacturing a color filter that can shorten the exposure step of irradiating energy and improve manufacturing efficiency. It is.

In order to achieve the above object, the present invention contains a light shielding part forming step for forming a light shielding part on a transparent substrate, and a photocatalyst and an organopolysiloxane so as to cover the transparent substrate and the light shielding part. A photocatalyst-containing layer forming step for forming a photocatalyst-containing layer; and a wettability changing pattern forming step for forming a wettability changing pattern in which the wettability of the photocatalyst-containing layer is changed by irradiating energy from the transparent substrate side; And a colored layer forming step of forming a colored layer by an inkjet method on the wettability change pattern,
In the wettability change pattern forming step, a color filter having a reflective substrate having a reflective layer capable of reflecting energy on the photocatalyst-containing layer side is arranged so that the reflective layer is on the photocatalyst-containing layer side A manufacturing method is provided.

  According to the present invention, in the wettability change pattern forming process in which exposure is performed, since the reflective substrate is disposed at a position opposite to the energy irradiation direction, the irradiated energy is transmitted through the photocatalyst containing layer. Since the photocatalyst is excited and the energy reflected by the reflective substrate excites the photocatalyst containing layer again, the wettability change of the wettability changing layer can be achieved in a short time. Thereby, the time of a wettability change pattern formation process can be shortened, and the manufacturing efficiency of a color filter can be improved.

Moreover, in this invention, it is preferable to have the photocatalyst processing layer containing a photocatalyst at least on the said reflective layer surface. By doing so, it is possible to further improve the rate of change of wettability of the wettability changing layer, thereby further reducing the time of the wettability changing pattern forming process and improving the production efficiency of the color filter. It is because it can improve significantly.
The present invention also provides a pattern-forming reflective substrate comprising a reflective layer capable of reflecting energy for exciting a photocatalyst, and a photocatalyst treatment layer formed on the surface of the reflective layer and containing at least a photocatalyst. provide. By using such a reflection substrate for pattern formation, the production efficiency of various pattern formation bodies using a photocatalyst can be improved.

  According to the present invention, the change in wettability of the wettability changing layer can be achieved in a short time. Thereby, the time of the wettability change pattern forming process can be shortened, and the production efficiency of the color filter can be improved.

Hereinafter, a color filter manufacturing method of the present invention and a pattern-forming reflective substrate that can also be used in the color filter manufacturing method will be described.
A. Method for Producing Color Filter The method for producing a color filter of the present invention comprises a light shielding part forming step for forming a light shielding part on a transparent substrate, a photocatalyst and an organopolysiloxane so as to cover the transparent substrate and the light shielding part. A photocatalyst-containing layer forming step for forming a photocatalyst-containing layer, and a wettability change pattern that forms a wettability change pattern in which the wettability of the photocatalyst-containing layer is changed by irradiating energy from the transparent substrate side A color filter manufacturing method comprising a forming step and a colored layer forming step of forming a colored layer on the wettability change pattern,
In the wettability change pattern forming step, the reflective substrate having a reflective layer capable of reflecting energy to the photocatalyst-containing layer side is arranged so that the reflective layer is on the photocatalyst-containing layer side. is there.

An example of the method for producing the color filter of the present invention will be specifically described with reference to the drawings. FIG. 1 shows a method for producing a color filter of the present invention. A light shielding part 2 made of resin is formed on a transparent substrate 1 (light shielding part forming step (FIG. 1A)), A photocatalyst-containing layer 3 is formed so as to cover the light shielding portion 2 and the transparent substrate 1 (photocatalyst-containing layer forming step (FIG. 2B)). Next, energy 4 is irradiated from the transparent substrate 1 side. (FIG. 2 (c)), a wettability change pattern composed of the lyophilic region 5 in which the wettability of the photocatalyst-containing layer 3 is changed and the liquid repellent region 6 in which the photocatalyst-containing layer 3 is not changed is formed (wetability change pattern). Forming step (FIG. 2 (d)) At this time, on the side where the photocatalyst-containing layer 3 is formed, the reflective substrate 9 on which the reflective layer 8 is formed on the base body 7, the reflective layer 8 is on the photocatalyst-containing layer 3 side. As a result, energy 4 is excited when passing through the photocatalyst-containing layer 3, Also would be excited by the energy reflected by the reflective layer 8 in al, it is possible to efficiently change in wettability.
Subsequently, the color filter 11 is obtained by forming the colored layer 10 on the lyophilic region 5 of the wettability change pattern by an ink jet apparatus.

According to the present invention, by using a reflective substrate having a reflective layer in the wettability change pattern forming step, the irradiated energy first excites the photocatalyst when passing through the photocatalyst-containing layer, and then the reflective layer. The photocatalyst-containing layer is irradiated again, and the photocatalyst in the photocatalyst-containing layer is excited again, and the photocatalyst can be excited twice by one energy irradiation. Thereby, it becomes possible to perform the said wettability change pattern formation process in a short time, and can aim at the fall of the manufacturing cost accompanying shortening of time. In addition, when changing the wettability of the photocatalyst-containing layer, since the light-shielding portion is formed, the colored layer can be formed without using a photomask or the like by irradiating the entire surface with energy from the transparent substrate side. The wettability of the photocatalyst containing layer only at the position to be formed can be changed.
Hereafter, the manufacturing method of the color filter of this invention is demonstrated in detail for every process.

1. Light-shielding part formation process In this invention, the light-shielding part formation process which forms a light-shielding part on a transparent base material first is performed (refer Fig.1 (a)). The light-shielding part formed in this step is formed on a transparent base material to be described later. When a color filter is used, the light-shielding portion shields the irradiated light and is irradiated in the wettability change pattern forming step. There is no particular limitation as long as it can shield energy. Such a method for forming the light shielding portion is appropriately selected and used depending on the shielding property against the required energy.

  For example, it may be formed by forming a metal thin film of chromium or the like having a thickness of about 1000 to 2000 mm by a sputtering method, a vacuum deposition method, or the like, and patterning the thin film. As this patterning method, a normal patterning method such as sputtering can be used.

  Alternatively, a method may be used in which a layer containing light-shielding particles such as carbon fine particles, metal oxides, inorganic pigments, and organic pigments in a resin binder is formed in a pattern. As the resin binder to be used, polyimide resin, acrylic resin, epoxy resin, polyacrylamide, polyvinyl alcohol, gelatin, casein, cellulose, or a mixture of one or more kinds, photosensitive resin, or O / A W emulsion type resin composition, for example, an emulsion of a reactive silicone can be used. The thickness of such a resin light-shielding portion can be set within a range of 0.5 to 10 μm. A generally used method such as a photolithography method or a printing method can be used as a method for forming such a resin light-shielding portion.

  Furthermore, in the present invention, the light shielding part can be formed by a thermal transfer method. This thermal transfer method usually involves placing a thermal transfer sheet having a light-to-heat conversion layer and a light-shielding part transfer layer on one side of a transparent film base material on the base material, and irradiating the area where the light-shielding part is formed with energy. The light-shielding part transfer layer is transferred onto the substrate to form a light-shielding part. The thickness of the light-shielding portion formed by such a thermal transfer method can usually be about 0.5 μm to 10.0 μm, particularly about 0.8 μm to 5.0 μm.

  The light shielding part transferred by the thermal transfer method is usually composed of a light shielding material and a binder, and inorganic particles such as carbon black and titanium black can be used as the light shielding material. The particle diameter of such a light-shielding material is preferably 0.01 μm to 1.0 μm, and more preferably 0.03 μm to 0.3 μm.

  Further, the binder is preferably a resin composition having thermoplasticity and thermosetting properties, has a thermosetting functional group, and has a softening point in the range of 50 ° C to 150 ° C, particularly 60 ° C. It is preferable to be comprised by the resin material which exists in the range of -120 degreeC, a hardening | curing agent, etc. Specific examples of such a material include a combination of an epoxy compound or epoxy resin having two or more epoxy groups in one molecule and a latent curing agent thereof. As a latent curing agent for epoxy resins, it does not have reactivity with epoxy groups up to a certain temperature, but when it reaches the activation temperature by heating, it changes to a molecular structure with reactivity with epoxy groups. A curing agent can be used. Specific examples include neutral salts and complexes of acidic or basic compounds having reactivity with epoxy resins, block compounds, high melting point bodies, and microcapsules. In addition to the above materials, the light-shielding part may contain a release agent, an adhesion assistant, an antioxidant, a dispersant, and the like.

  In the present invention, a primer layer may be formed between the photocatalyst containing layer and the light shielding part. Although the action and function of this primer layer are not necessarily clear, by forming the primer layer, it becomes a factor that inhibits the above-mentioned wettability change of the photocatalyst-containing layer from the light-shielding part and the opening existing between the light-shielding parts. This is considered to exhibit a function of preventing diffusion of impurities, particularly residues generated when the light shielding portion is patterned, and impurities. Therefore, by forming the primer layer, the wettability of the photocatalyst containing layer can be changed with high sensitivity, and as a result, a high resolution pattern can be obtained.

  In the present invention, the primer layer prevents the impurities present in the openings formed between the light shielding portions as well as the light shielding portions from affecting the action of the photocatalyst. Therefore, the primer layer includes the openings. It is preferable that it is formed over the entire light shielding portion.

  The primer layer in the present invention is not particularly limited as long as the primer layer is formed so that the light-shielding portion and the photocatalyst-containing layer are not in contact with each other.

The material constituting the primer layer is not particularly limited, but an inorganic material that is not easily decomposed by the action of the photocatalyst is preferable. Specific examples include amorphous silica. When such amorphous silica is used, the precursor of the amorphous silica is represented by the general formula SiX ₄ and X is a silicon compound such as halogen, methoxy group, ethoxy group, or acetyl group, Silanol which is a hydrolyzate thereof or polysiloxane having an average molecular weight of 3000 or less is preferable.

  The thickness of the primer layer is preferably in the range of 0.001 μm to 1 μm, particularly preferably in the range of 0.001 μm to 0.1 μm.

  As a transparent substrate on which such a light-shielding part is formed, a light transmittance of a backlight or the like is good, and a light transmittance that is irradiated in a wettability change pattern forming process described later is good If it is, it will not specifically limit. Specifically, transparent flexible materials such as quartz glass, Pyrex (registered trademark) glass, and synthetic quartz plates, or flexible flexible materials such as transparent resin films and optical resin plates, etc. Can be mentioned.

2. Photocatalyst-containing layer forming step Next, in the present invention, a photocatalyst-containing layer forming step of forming a photocatalyst-containing layer containing a photocatalyst and an organopolysiloxane is performed so as to cover the transparent base material and the light-shielding part (see FIG. 1 (b)).

  The photocatalyst-containing layer in the present invention is formed by dispersing a photocatalyst and an organopolysiloxane in a solvent together with other additives as necessary to prepare a coating solution, and coating the coating solution on a transparent substrate. can do. As the solvent to be used, alcohol-based organic solvents such as ethanol and isopropanol are preferable. The application can be performed by a known application method such as spin coating, spray coating, dip coating, roll coating, or bead coating. When an ultraviolet curable component is contained as the binder, the photocatalyst-containing layer can be formed by performing a curing treatment by irradiating ultraviolet rays. At this time, the thickness of the photocatalyst-containing layer is preferably in the range of 0.05 to 10 μm. If it is thinner than the above range, it is not preferable because the wettability change efficiency of the surface of the photocatalyst containing layer is low, and if it is thicker than the above range, the distance between the light shielding portion and the colored layer is increased, When a filter is used in a liquid crystal display device, problems such as light leakage from a backlight may occur, which is not preferable.

  Since the photocatalyst-containing layer thus formed contains a photocatalyst and an organopolysiloxane, the surface wettability can be changed by the action of the photocatalyst when irradiated with energy. The formed region can be a lyophilic region, and the region not irradiated with energy can be a liquid repellent region.

  In the present invention, the contact angle with a liquid having a surface tension of 30 mN / m is 10 ° or more in a contact angle with a liquid with a surface tension of 30 mN / m in a portion not irradiated with energy, that is, a liquid repellent region. In particular, the contact angle with a liquid having a surface tension of 20 mN / m is preferably 10 ° or more. This is because the part that is not irradiated with energy is a part that requires liquid repellency, so when the contact angle with the liquid is small, the liquid repellency is not sufficient. For example, a colored layer described later is formed. When the colored layer forming coating liquid is applied by an inkjet method and cured, the colored layer forming coating liquid may adhere to the liquid-repellent region. This is because it becomes difficult to form a colored layer.

  The photocatalyst-containing layer has a contact angle with a liquid of 40 mN / m of less than 9 °, preferably a liquid with a surface tension of 50 mN / m, in a portion irradiated with energy, that is, a lyophilic region. The layer is preferably such that the contact angle with a liquid having a surface tension of 10 ° or less, particularly 60 mN / m, is 10 ° or less. When the contact angle with the liquid in the energy irradiated part, that is, the lyophilic region is high, for example, the colored layer forming coating liquid for forming the colored layer may be repelled in the lyophilic region. This is because, for example, when the coating liquid for forming a colored layer is applied by an ink jet method, the coating liquid for forming a colored layer is not sufficiently spread and spread, and it may be difficult to form a colored layer.

  In addition, the contact angle with the liquid here is measured using a contact angle measuring instrument (Kyowa Interface Science Co., Ltd. CA-Z type) with a liquid having various surface tensions (from the microsyringe to the liquid. 30 seconds after dropping), and the result was obtained or the result was graphed. In this measurement, as a liquid having various surface tensions, a wetting index standard solution manufactured by Pure Chemical Co., Ltd. was used.

  The photocatalyst-containing layer used in the present invention contains fluorine in the photocatalyst-containing layer, and when the fluorine content on the surface of the photocatalyst-containing layer is irradiated with energy to the photocatalyst-containing layer, The photocatalyst-containing layer may be formed so as to be lower than that before energy irradiation, and is decomposed by the action of the photocatalyst by energy irradiation, thereby changing the wettability on the photocatalyst-containing layer. You may form so that a substance may be included.

  Hereinafter, the photocatalyst, organopolysiloxane, and other components constituting such a photocatalyst-containing layer will be described.

a. Photocatalyst First, the photocatalyst used in the present invention will be described. Examples of the photocatalyst used in the present invention include titanium dioxide (TiO ₂ ), zinc oxide (ZnO), tin oxide (SnO ₂ ), strontium titanate (SrTiO ₃ ), tungsten oxide (WO ₃ ), which are known as photo semiconductors. Bismuth oxide (Bi ₂ O ₃ ) and iron oxide (Fe ₂ O ₃ ) can be mentioned, and one or a mixture of two or more selected from these can be used.

  In the present invention, titanium dioxide is particularly preferably used because it has a high band gap energy, is chemically stable, has no toxicity, and is easily available. Titanium dioxide includes an anatase type and a rutile type, and both can be used in the present invention, but anatase type titanium dioxide is preferred. Anatase type titanium dioxide has an excitation wavelength of 380 nm or less.

  Examples of such anatase type titanium dioxide include hydrochloric acid peptizer type anatase type titania sol (STS-02 manufactured by Ishihara Sangyo Co., Ltd. (average particle size 7 nm), ST-K01 manufactured by Ishihara Sangyo Co., Ltd.), nitric acid solution An anatase type titania sol (TA-15 manufactured by Nissan Chemical Co., Ltd. (average particle size 12 nm)) and the like can be mentioned.

  The smaller the particle size of the photocatalyst, the more effective the photocatalytic reaction occurs. The average particle size is preferably 50 nm or less, and it is particularly preferable to use a photocatalyst of 20 nm or less.

  The content of the photocatalyst in the photocatalyst containing layer used in the present invention can be set in the range of 5 to 60% by weight, preferably 20 to 40% by weight. This is because the adhesiveness to the ITO layer described later can be improved.

b. Organopolysiloxane Next, the organopolysiloxane used in the present invention will be described. The organopolysiloxane used in the present invention is not particularly limited as long as it can change the wettability of the surface of the photocatalyst-containing layer by the action of the photocatalyst accompanying energy irradiation. Those having a high binding energy that is not decomposed by photoexcitation of the photocatalyst and having an organic substituent that is decomposed by the action of the photocatalyst are preferable. Specifically, (1) an organopolysiloxane that exhibits high strength by hydrolyzing and polycondensing chloro or alkoxysilane by sol-gel reaction or the like, and (2) a reactive silicone having excellent water repellency and oil repellency. Cross-linked organopolysiloxanes can be mentioned.

In the case of (1) above, the general formula:
Y _n SiX _(4-n)
(Where Y is an alkyl group, fluoroalkyl group, vinyl group, amino group, phenyl group, chloroalkyl group, isocyanate group, or epoxy group, or an organic group containing these, and X is an alkoxyl group, acetyl group, or Represents halogen, n is an integer from 0 to 3)
It is preferable that it is the organopolysiloxane which is a 1 type, or 2 or more types of hydrolysis condensate or cohydrolysis condensate of the silicon compound shown by these. Here, the alkoxy group represented by X is preferably a methoxy group, an ethoxy group, a propoxy group, or a butoxy group. Moreover, it is preferable that the carbon number of the whole organic group shown by Y exists in the range of 1-20, especially in the range of 5-10.

  Thus, when the photocatalyst-containing layer is formed, the surface can be made liquid-repellent by Y constituting the organopolysiloxane, and the Y is decomposed by the action of the photocatalyst accompanying energy irradiation. This is because it can be made lyophilic.

In particular, when an organopolysiloxane in which Y constituting the organopolysiloxane is a fluoroalkyl group is used, the photocatalyst-containing layer before energy irradiation can be made particularly high in liquid repellency. When high liquid repellency is required, it is preferable to use an organopolysiloxane having these fluoroalkyl groups. Specific examples of such organopolysiloxanes include one or more of the following hydroalkyl silanes, co-hydrolysis condensates, and are generally known as fluorine-based silane coupling agents. Can be used.
_{CF 3 (CF 2) 3 CH} 2 CH 2 Si (OCH 3) 3;
_{CF 3 (CF 2) 5 CH} 2 CH 2 Si (OCH 3) 3;
_{CF 3 (CF 2) 7 CH} 2 CH 2 Si (OCH 3) 3;
_{CF 3 (CF 2) 9 CH} 2 CH 2 Si (OCH 3) 3;
(CF ₃ ) ₂ CF (CF ₂ ) ₄ CH ₂ CH ₂ Si (OCH ₃ ) ₃ ;
_{(CF 3) 2 CF (CF} 2) 6 CH 2 CH 2 Si (OCH 3) 3;
_{(CF 3) 2 CF (CF} 2) 8 CH 2 CH 2 Si (OCH 3) 3;
_{CF 3 (C 6 H 4)} C 2 H 4 Si (OCH 3) 3;
_{CF 3 (CF 2) 3 (} C 6 H 4) C 2 H 4 Si (OCH 3) 3;
_{CF 3 (CF 2) 5 (} C 6 H 4) C 2 H 4 Si (OCH 3) 3;
_{CF 3 (CF 2) 7 (} C 6 H 4) C 2 H 4 Si (OCH 3) 3;
_{CF 3 (CF 2) 3 CH} 2 CH 2 SiCH 3 (OCH 3) 2;
_{CF 3 (CF 2) 5 CH} 2 CH 2 SiCH 3 (OCH 3) 2;
_{CF 3 (CF 2) 7 CH} 2 CH 2 SiCH 3 (OCH 3) 2;
_{CF 3 (CF 2) 9 CH} 2 CH 2 SiCH 3 (OCH 3) 2;
_{(CF 3) 2 CF (CF} 2) 4 CH 2 CH 2 SiCH 3 (OCH 3) 2;
_{(CF 3) 2 CF (CF} 2) 6 CH 2 CH 2 Si CH 3 (OCH 3) 2;
_{(CF 3) 2 CF (CF} 2) 8 CH 2 CH 2 Si CH 3 (OCH 3) 2;
_{CF 3 (C 6 H 4)} C 2 H 4 SiCH 3 (OCH 3) 2;
_{CF 3 (CF 2) 3 (} C 6 H 4) C 2 H 4 SiCH 3 (OCH 3) 2;
_{CF 3 (CF 2) 5 (} C 6 H 4) C 2 H 4 SiCH 3 (OCH 3) 2;
_{CF 3 (CF 2) 7 (} C 6 H 4) C 2 H 4 SiCH 3 (OCH 3) 2;
_{CF 3 (CF 2) 3 CH} 2 CH 2 Si (OCH 2 CH 3) 3;
_{CF 3 (CF 2) 5 CH} 2 CH 2 Si (OCH 2 CH 3) 3;
_{CF 3 (CF 2) 7 CH} 2 CH 2 Si (OCH 2 CH 3) 3;
_{CF 3 (CF 2) 9 CH} 2 CH 2 Si (OCH 2 CH 3) 3;
_{CF 3 (CF 2) 7 SO} 2 N (C 2 H 5) C 2 H 4 CH 2 Si (OCH 3) 3.

  Examples of the reactive silicone (2) include compounds having a skeleton represented by the following general formula.

However, n is an integer of 2 or more, R ^1, R ² are each a substituted or unsubstituted alkyl having 1 to 10 carbon atoms, alkenyl, aryl or cyanoalkyl group, the total molar ratio of 40% or less Vinyl, phenyl and phenyl halide. Further, those in which R ¹ and R ² are methyl groups are preferable because the surface energy becomes the smallest, and the methyl groups are preferably 60% or more by molar ratio. In addition, the chain end or side chain has at least one reactive group such as a hydroxyl group in the molecular chain.

  The organopolysiloxane is preferably contained in the photocatalyst-containing layer in an amount of 5 to 90% by weight, especially about 30 to 60% by weight.

c. Other Substances In the photocatalyst-containing layer used in the present invention, a stable organosilicon compound that does not undergo a crosslinking reaction, such as dimethylpolysiloxane, may be mixed with a binder together with the organopolysiloxane. Furthermore, examples of the binder include polysiloxanes having a high binding energy that does not cause the main skeleton to be decomposed by photoexcitation of the photocatalyst, or that do not have an organic substituent, or have an organic substituent. You may contain what hydrolyzed and polycondensed methoxysilane, tetraethoxysilane, etc.

  Furthermore, in order to assist the function of changing the wettability of the organopolysiloxane, a decomposition substance that is decomposed by energy irradiation may be included. Examples of such a decomposing substance include a surfactant having a function of decomposing by the action of a photocatalyst and changing the wettability of the photocatalyst-containing layer surface by decomposing. Specifically, hydrocarbons such as NIKKOL BL, BC, BO, BB series manufactured by Nikko Chemicals Co., Ltd., ZONYL FSN, FSO manufactured by DuPont, Surflon S-141, 145 manufactured by Asahi Glass Co., Ltd., Dainippon Megafac F-141, 144 manufactured by Ink Chemical Industry Co., Ltd., Footgent F-200, F251 manufactured by Neos Co., Ltd., Unidyne DS-401, 402 manufactured by Daikin Industries, Ltd., Fluorard FC-170 manufactured by 3M Co., Ltd. Fluorine-based or silicone-based nonionic surfactants such as 176, and cationic surfactants, anionic surfactants, and amphoteric surfactants can also be used.

  Besides surfactants, polyvinyl alcohol, unsaturated polyester, acrylic resin, polyethylene, diallyl phthalate, ethylene propylene diene monomer, epoxy resin, phenol resin, polyurethane, melamine resin, polycarbonate, polyvinyl chloride, polyamide, polyimide Styrene butadiene rubber, chloroprene rubber, polypropylene, polybutylene, polystyrene, polyvinyl acetate, nylon, polyester, polybutadiene, polybenzimidazole, polyacrylonitrile, epichlorohydrin, polysulfide, polyisoprene, oligomers, polymers, and the like.

d. In addition, in the present invention, when the photocatalyst containing layer contains fluorine, and the fluorine content on the surface of the photocatalyst containing layer is irradiated with energy to the photocatalyst containing layer, the photocatalyst containing layer is irradiated with energy by the action of the photocatalyst. It is preferable that the photocatalyst-containing layer is formed so as to be lower than before. Thereby, the pattern which consists of a part with little content of fluorine can be easily formed by irradiating energy with a pattern so that it may mention later. Here, fluorine has an extremely low surface energy. Therefore, the surface of a substance containing a large amount of fluorine has a smaller critical surface tension. Therefore, the critical surface tension of the portion having a small fluorine content is larger than the critical surface tension of the surface of the portion having a large fluorine content. This means that the portion with a low fluorine content is a lyophilic region compared to the portion with a high fluorine content. Therefore, forming a pattern composed of a portion having a lower fluorine content than the surrounding surface forms a pattern of a lyophilic region in the liquid repellent region.

  Therefore, when such a photocatalyst-containing layer is used, the pattern of the lyophilic region can be easily formed in the liquid-repellent region by irradiating the pattern with energy. This is because a high-definition colored layer can be formed when the colored layer forming coating solution is applied.

  As described above, the fluorine content contained in the photocatalyst containing layer containing fluorine is not irradiated with energy in the lyophilic region having a low fluorine content formed by energy irradiation. When the fluorine content of the part is 100, it is 10 or less, preferably 5 or less, particularly preferably 1 or less.

  By setting it within such a range, it is possible to make a large difference in lyophilicity between the energy-irradiated portion and the unirradiated portion. Therefore, for example, by attaching a coating liquid for forming a colored layer to such a photocatalyst-containing layer, it becomes possible to accurately form a colored layer only in a lyophilic region having a reduced fluorine content. This is because a good color filter can be obtained. This rate of decrease is based on weight.

  For the measurement of the fluorine content in the photocatalyst-containing layer, various commonly used methods can be used. For example, X-ray photoelectron spectroscopy (ES-ray photoelectron spectroscopy, ESCA) for Chemical Analysis)), and any method that can quantitatively measure the amount of fluorine on the surface, such as X-ray fluorescence analysis and mass spectrometry, is not particularly limited.

  In the present invention, as described above, titanium dioxide is preferably used as the photocatalyst. When titanium dioxide is used in this way, the fluorine content contained in the photocatalyst-containing layer is X-ray photoelectron. When analyzed and quantified by spectroscopy, when the titanium (Ti) element is defined as 100, the fluorine (F) element is in a ratio of 500 or more, preferably 800 or more, particularly preferably 1200 or more. It is preferable that the element is contained on the surface of the photocatalyst containing layer.

  Fluorine (F) is included in the photocatalyst-containing layer to such an extent that the critical surface tension on the photocatalyst-containing layer can be sufficiently lowered, so that the liquid repellency on the surface can be secured, thereby irradiating energy with the pattern This is because the difference in wettability with the lyophilic region on the surface of the pattern portion where the fluorine content is reduced can be increased, and the accuracy of the color filter finally obtained can be improved.

  Further, in such a color filter, the fluorine content in the lyophilic region formed by pattern irradiation with energy is 50 or less when the titanium (Ti) element is 100, preferably It is preferably contained in a ratio of 20 or less, particularly preferably 10 or less.

  If the fluorine content in the photocatalyst-containing layer can be reduced to this extent, sufficient lyophilicity can be obtained for forming a color filter, and the liquid repellency of the portion where the energy is not irradiated can be obtained. Due to the difference in wettability, the color filter can be formed with high accuracy, and a color filter with high utility value can be obtained.

3. Next, the wettability change pattern forming process in the present invention will be described. In the wettability change pattern forming step in the present invention, the reflective substrate having a reflective layer capable of reflecting energy on the photocatalyst containing layer side is disposed so that the reflective layer is on the photocatalyst containing layer side, and the transparent substrate This is a step of forming a wettability change pattern in which the wettability of the photocatalyst-containing layer is changed by irradiating energy from the side (see FIGS. 1C and 1D).
The feature of the present invention lies in the use of a reflective substrate in this wettability change pattern forming step, and by using this reflective substrate, the irradiated energy is reflected by the reflective layer and irradiated again to the photocatalyst-containing layer. Therefore, the efficiency of change in wettability of the photocatalyst-containing layer can be improved. Thereby, the said wettability change pattern formation process can be performed in a short time, and the manufacturing efficiency of a color filter can be improved.

(Irradiated energy)
The energy with which the photocatalyst-containing layer is irradiated is not particularly limited as long as the energy can change the wettability of the photocatalyst-containing layer. The energy irradiation (exposure) in the present invention is a concept including irradiation of any energy ray capable of changing the wettability of the photocatalyst-containing layer surface, and is limited to irradiation with ultraviolet light or visible light. is not.

  Usually, the wavelength of light used for such energy irradiation is set in a range of 400 nm or less, preferably in a range of 150 nm to 380 nm or less. This is because, as described above, the preferred photocatalyst used in the photocatalyst-containing layer is titanium dioxide, and light having the above-described wavelength is preferable as the energy for activating the photocatalytic action by the titanium dioxide.

  Examples of light sources that can be used for such energy irradiation include mercury lamps, metal halide lamps, xenon lamps, excimer lamps, and various other light sources. In addition to the method of performing pattern irradiation using a light mask using a light source as described above, it is also possible to use a method of drawing and irradiating in a pattern using a laser such as excimer or YAG.

  In addition, the irradiation amount of energy at the time of energy irradiation is set to an irradiation amount necessary for changing the wettability of the surface of the photocatalyst containing layer by the action of the photocatalyst in the photocatalyst containing layer.

(Reflective substrate)
Next, the reflective substrate used in the wettability change pattern forming process, which is also a feature of the present invention, will be described.
The reflective substrate used in the present invention is not particularly limited as long as it has a reflective layer that reflects energy capable of changing the wettability of the photocatalyst-containing layer, and the reflective substrate is formed of a reflective layer. The reflective layer may be formed on the substrate.

a. Reflective layer As described above, the reflective layer used in the present invention has a self-supporting property, and may itself be a reflective substrate or may be formed on a substrate. Good.
Although it does not specifically limit as a material used for a reflection layer, A metal material is used suitably, Specifically, it has aluminum, silver, iron, the reflective substrate which has a vapor deposition aluminum layer, and a vapor deposition silver layer. A reflective substrate or the like is used.
When the reflective layer is formed on the substrate, a method is generally used in which the above-described metal is deposited on the substrate surface by vacuum deposition or the like. Further, when the reflective layer has self-supporting properties, a metal plate or the like having one surface with a mirror finish can be used.

  The reflective layer surface is preferably a smooth surface. This is because if the surface is not smooth, irregular reflection occurs on the surface of the reflective layer, which may reduce patterning accuracy. Specifically, the surface roughness Ra is preferably in the range of 0.1 nm to 20 nm.

b. Substrate The substrate used in the present invention is not particularly limited as long as the surface is a plate having a certain level of smoothness, and any of organic and inorganic materials can be used.

c. Photocatalyst treatment layer In the present invention, a photocatalyst treatment layer containing at least a photocatalyst may be formed on the surface of the reflection layer. By forming such a photocatalyst-treated layer on the surface of the reflective layer, it becomes possible to further change the wettability of the surface of the photocatalyst-containing layer by the action of the photocatalyst in the photocatalyst-treated layer in addition to the efficiency by reflected light. This is because it is possible to further shorten the wettability change pattern forming step and to efficiently manufacture the color filter.
The photocatalyst treatment layer used in the present invention is not particularly limited as long as the photocatalyst in the photocatalyst treatment layer changes the wettability of the above-described photocatalyst-containing layer, and includes a photocatalyst and a binder. It may be a film formed with a photocatalyst alone. Further, the surface characteristics may be particularly lyophilic or lyophobic.

The photocatalyst used for the photocatalyst treatment layer is the same as that described for the photocatalyst-containing layer, and a description thereof is omitted here.
In the present invention, the photocatalyst treatment layer may be formed by the photocatalyst alone as described above, or may be formed by mixing with a binder.
In the case of a photocatalyst treatment layer consisting of only a photocatalyst, the efficiency with respect to the change in characteristics on the photocatalyst containing layer is improved, which is advantageous in terms of cost such as shortening of the treatment time. On the other hand, in the case of a photocatalyst treatment layer comprising a photocatalyst and a binder, there is an advantage that the formation of the photocatalyst treatment layer is easy.

  Examples of a method for forming a photocatalyst treatment layer composed of only a photocatalyst include a method using a vacuum film forming method such as a sputtering method, a CVD method, or a vacuum deposition method. By forming the photocatalyst treatment layer by vacuum film-forming method, it is possible to make a photocatalyst treatment layer that is a uniform film and contains only the photocatalyst, thereby uniformly changing the wettability on the photocatalyst containing layer Since it consists only of a photocatalyst, it is possible to efficiently change the wettability on the photocatalyst-containing layer as compared with the case where a binder is used.

  In addition, as another example of a method for forming a photocatalyst treatment layer composed of only a photocatalyst, for example, when the photocatalyst is titanium dioxide, amorphous titania is formed on a base material, and then the phase is changed to crystalline titania by firing. Etc. As the amorphous titania used here, for example, hydrolysis, dehydration condensation, tetraethoxytitanium, tetraisopropoxytitanium, tetra-n-propoxytitanium, tetrabutoxytitanium, titanium inorganic salts such as titanium tetrachloride and titanium sulfate, An organic titanium compound such as tetramethoxytitanium can be obtained by hydrolysis and dehydration condensation in the presence of an acid. Next, it can be modified to anatase titania by baking at 400 ° C. to 500 ° C. and modified to rutile type titania by baking at 600 ° C. to 700 ° C.

In the case of using a binder, those having a high binding energy such that the main skeleton of the binder is not decomposed by the photoexcitation of the photocatalyst are preferable, and examples thereof include organopolysiloxane. Since it is the same as that described in the layer, description thereof is omitted here.
An amorphous silica precursor can be used as the binder. This amorphous silica precursor is represented by the general formula SiX _4, X is a halogen, a methoxy group, an ethoxy group or a silicon compound an acetyl group or the like, and silanol or average molecular weight of 3,000 or less, their hydrolysates Polysiloxane is preferred.

Specific examples include tetraethoxysilane, tetraisopropoxysilane, tetra-n-propoxysilane, tetrabutoxysilane, and tetramethoxysilane. In this case, the amorphous silica precursor and the photocatalyst particles are uniformly dispersed in a non-aqueous solvent, and hydrolyzed with moisture in the air on the substrate to form silanol, and then at room temperature. A photocatalyst-treated layer can be formed by dehydration condensation polymerization with. If dehydration condensation polymerization of silanol is carried out at 100 ° C. or higher, the degree of polymerization of silanol increases and the strength of the film surface can be improved. Moreover, these binders can be used individually or in mixture of 2 or more types.
Such a photocatalyst treatment layer preferably has a high transmittance for the energy for exciting the photocatalyst. This is because, when the transmittance is low, the amount of energy reflected by the reflective layer is reduced, and the improvement in the wettability change efficiency due to the reflected energy is hindered.

From such a point, the film thickness of the photocatalyst treatment layer is preferably in the range of 0.05 μm to 1 μm, particularly in the range of 0.1 μm to 0.5 μm. When the film thickness is 0.05 μm or less, the sensitivity of the photocatalyst treatment layer may be reduced, and when the film thickness is 1 μm or more, the transmittance of the photocatalyst treatment layer with respect to energy is low. Because it becomes a thing.
The photocatalyst treatment layer may be formed directly on the surface of the reflective layer, or may be formed via an intermediate layer that is transparent to the energy applied.

(Distribution of reflective substrate)
As described above, the reflective substrate is disposed such that the reflective layer faces the photocatalyst-containing layer, and is irradiated with the energy. At this time, it is preferable that the gap between the reflective layer and the photocatalyst-containing layer is arranged to be as narrow as possible. This is because when this gap is wide, there is a risk of adversely affecting the formation of a highly accurate pattern due to the influence of irregular reflection on the surface of the reflective layer.
The specific gap is preferably in the range of 0.1 mm to 5 mm, particularly in the range of 0.5 mm to 3 mm. In addition, when the above-mentioned photocatalyst processing layer is formed on the reflective layer surface, the gap between the photocatalyst processing layer and the photocatalyst containing layer is affected by the photocatalyst in the photocatalyst processing layer on the wettability of the photocatalyst containing layer. It is preferable that the gap is such that the gap can be exerted, and specifically, it is preferable that the gap is arranged with a gap of 200 μm or less.

4). Colored layer forming step Next, the colored layer forming step in the present invention will be described. The colored layer forming step in the present invention is a step of forming a colored layer on the wettability changing pattern by an ink jet method (see FIG. 1 (e)).
The ink jet device used in this step is not particularly limited, but is a method in which charged ink is continuously ejected and controlled by a magnetic field, a method in which ink is ejected intermittently using a piezoelectric element, and ink is used. An ink jet apparatus using various methods such as a method of heating and intermittently utilizing the foaming can be used, and among them, a method of intermittently ejecting ink using a piezoelectric element is preferable. .

In this step, the colored layer is specifically formed on the lyophilic region along the wettability changing pattern in which the wettability of the photocatalyst containing layer is changed as described above.
Such a colored layer is usually formed of three colors of red (R), green (G), and blue (B). The colored pattern shape in the colored layer can be a known arrangement such as a stripe type, a mosaic type, a triangle type, or a four-pixel arrangement type, and the colored area can be arbitrarily set.
Since the coating liquid for forming a colored layer used in this step can be the same as that used for a colored layer of a general color filter, detailed description thereof is omitted here.

5). Others In the present invention, a step of forming other members usually formed in a color filter, such as a step of forming an ITO film as a transparent electrode layer or a step of forming an overcoat layer, may be performed. Since these are also the same as the manufacturing method of a normal color filter, description here is omitted.

B. Next, the reflective substrate for pattern formation of the present invention will be described. The reflective substrate for pattern formation of the present invention comprises a reflective layer capable of reflecting energy for exciting a photocatalyst, and a photocatalyst treatment layer formed on the surface of the reflective layer and containing at least a photocatalyst. It is. By using such a reflective substrate for pattern formation, for example, it is possible to efficiently produce a color filter as described in “A. Color filter production method” above.

  Since the reflective layer and the photocatalyst treatment layer, and the substrate, etc. constituting the reflective substrate for pattern formation of the present invention are the same as those described in the above “A. Color filter manufacturing method”, the description here Omitted.

The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.
For example, the reflection substrate for pattern formation described in the above-mentioned “B. reflection substrate for pattern formation” is not only for the pattern formation body containing a photocatalyst as described in “A. Color filter manufacturing method”, If it is a pattern formation body which has the characteristic change layer in which the characteristic of a surface changes by the effect | action of a photocatalyst on the surface, it can be used also for the thing which does not contain a photocatalyst.

  Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples.

<Example 1>
1. Formation of light shielding portion First, a light shielding material having the following composition was applied on a soda glass substrate having a thickness of 1.1 mm, and then prebaked at 100 ° C. for 15 minutes to dry the light shielding material to form a film. At this time, the light shielding material was applied by spin coating. The spin coating conditions were 1500 rpm / min.
・ Carbon black (black pigment) 28.5%
-Partially cyclized polyisoprene (negative photopolymer) 15.0%
・ Aromatic bisazide (photosensitive agent) 1.5%
・ Other additives 0.3%
・ Polyethylene glycol monomethyl ether acetate (solvent)
54.7%
Next, the thin film of the light shielding material formed as described above was irradiated with ultraviolet rays through a photomask, exposed at an exposure amount of 300 mJ / cm ² , developed and rinsed to form a light shielding portion. For development, a 0.1% NaCO ₃ aqueous solution was used as a developer. Thereafter, the light-shielding part obtained above was dried and then post-baked at 200 ° C. for 10 minutes to obtain a lattice-type light-shielding part having a film thickness of 1.2 μm, a line width of 30 μm, and an opening of 100 μm × 200 μm.

2. Formation of a photocatalyst containing layer 0.4 g of MF-160E (manufactured by Tochem Products Co., Ltd.) having 30 g of isopropyl alcohol and fluoroalkylsilane as main components and 3 g of trimethoxymethylsilane (TSL8113 manufactured by Toshiba Silicone Co., Ltd.) 20 g of ST-K01 (manufactured by Ishihara Sangyo Co., Ltd.), which is a titanium oxide aqueous dispersion that is a photocatalyst, was mixed and stirred at 100 ° C. for 20 minutes. This was diluted 3 times with isopropyl alcohol to obtain a composition for a photocatalyst-containing layer.
A transparent photocatalyst-containing layer (thickness 0.2 μm) is formed by applying the composition to a transparent substrate made of soda glass on which the light-shielding part is formed, using a spin coater and performing a drying treatment at 150 ° C. for 10 minutes. Formed.

3. Confirmation of formation of lyophilic region by exposure The exposed portion is formed by exposing the photocatalyst-containing layer through a mask with a mercury lamp (wavelength 365 nm) at an illuminance of 70 mW / cm ² for 50 seconds to form an exposed portion, and an unexposed portion and an exposed portion The contact angle with the liquid was measured. In the non-exposed area, a contact angle measuring device (CA-Z type manufactured by Kyowa Interface Science Co., Ltd.) is used for the contact angle with a liquid having a surface tension of 30 mN / m (manufactured by Pure Chemical Co., Ltd., ethylene glycol monoethyl ether) As a result of measurement (30 seconds after dropping a droplet from the microsyringe), it was 30 degrees. In the exposed area, the contact angle with a liquid having a surface tension of 50 mN / m (manufactured by Junsei Co., Ltd., wetting index standard solution No. 50) was measured in the same manner, and as a result, it was 7 degrees. As described above, it was confirmed that the exposed portion became a lyophilic region as compared with the non-exposed portion, and pattern formation was possible due to the difference in wettability between the exposed portion and the non-exposed portion.

4). Next, the light shielding portion is formed by making the photocatalyst containing layer face the aluminum surface of the glass plate on which 0.2 μm of aluminum is deposited so that the gap is 0.5 mm. Full exposure was performed from the backside. The exposure conditions were a mercury lamp (wavelength 365 nm) with an illuminance of 70 mW / cm ² for 20 seconds, and the colored layer exposure part was made lyophilic.
Next, thermal curing of each color of RGB including 5 parts by weight of a pigment, 20 parts by weight of a solvent, 70 parts by weight of an acrylic acid / benzyl acrylate copolymer, and 5 parts by weight of a bifunctional epoxy-containing monomer is performed using each RGB inkjet device. The polyepoxy acrylate ink was attached to the lyophilic colored layer exposure area and colored, and cured by heat treatment at 150 ° C. for 30 minutes. Here, for each of the red, green, and blue inks, the solvent is polyethylene glycol monomethyl ethyl acetate, the pigment is CI Pigment Red 177 for red ink, CI Pigment Green 36 for green ink, and CI Pigment Green 36 for blue ink Pigment Blue 15+ CI Pigment Violet 23 was used.
As a result, an RGB stripe color filter having a line width of 100 μm and a light shielding portion of 30 μm was obtained.

<Example 2>
In place of the counter aluminum substrate of Example 1, a photocatalyst treatment layer with a 0.2 μm photocatalyst treatment layer was formed on the aluminum deposition surface by the same method as “2. Formation of photocatalyst containing layer” of Example 1. The same procedure as in Example 1 was performed, except that a reflection plate was used, the gap between the photocatalyst-containing layer and the photocatalyst treatment layer was 0.2 mm, and the entire surface was exposed from the back surface where no light shielding portion was formed.
As a result, in Example 1, a stripe color filter was formed after 20 seconds of exposure, but in this experiment, even if the exposure time was further reduced to 10 seconds, the same stripe color filter was formed, and an improvement in sensitivity was observed. It was.

<Comparative Example 1>
As an exposure method, a counter aluminum substrate was not used, and back exposure was not performed, except that pattern exposure was performed for 20 seconds at a illuminance of 70 mW / cm ² with a mercury lamp (wavelength 365 nm) through a mask on the photocatalyst containing layer. When a color filter was prepared in the same manner as in Example 1, the colored ink did not spread in the colored layer, and white spots were generated.
By performing the exposure for 50 seconds, the difference in wettability is finally increased, and the color filter can be formed.

It is process drawing which shows an example of the manufacturing method of the color filter of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Transparent base material 2 ... Light-shielding part 3 ... Photocatalyst containing layer 4 ... Energy 8 ... Reflective layer 9 ... Reflective substrate 10 ... Colored layer 11 ... Color filter

Claims (1)

A light shielding part forming step of forming a light shielding part on the transparent substrate;
A photocatalyst-containing layer forming step of forming a photocatalyst-containing layer containing a photocatalyst and an organopolysiloxane so as to cover the transparent substrate and the light-shielding portion;
A wettability change pattern forming step of forming a wettability change pattern in which the wettability of the photocatalyst containing layer is changed by irradiating energy from the transparent substrate side;
A colored layer forming step of forming a colored layer by an inkjet method on the wettability change pattern,
In the wettability change pattern forming step , a reflective substrate having a reflective layer capable of reflecting energy to the photocatalyst-containing layer side is disposed such that the reflective layer is on the photocatalyst-containing layer side ,
A photocatalyst treatment layer containing at least a photocatalyst is formed on the reflective layer surface,
The method for producing a color filter, wherein the reflective substrate is arranged in the wettability change pattern forming step so that a gap between the photocatalyst processing layer and the photocatalyst containing layer is 200 μm or less .

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