JP5326848B2 - Method for producing curable resin composition for colored layer, method for producing color filter, and curable resin composition for colored layer - Google Patents

Description

  The present invention relates to a method for producing a curable resin composition for a colored layer, a method for producing a color filter, and a curable resin composition for a colored layer capable of controlling retardation in the thickness direction of the colored layer.

  The liquid crystal display device has features such as power saving, light weight, thinness, and the like, and has rapidly spread in recent years in place of the conventional CRT display. As a general liquid crystal display device, as shown in FIG. 8, a liquid crystal cell 101, an incident-side polarizing plate 102A, and an outgoing-side polarizing plate 102B can be exemplified. The polarizing plates 102A and 102B are configured to selectively transmit only linearly polarized light having a vibration surface in a predetermined vibration direction, and crossed Nicols so that the vibration directions are perpendicular to each other. It is arranged to face each other. The liquid crystal cell 101 includes a large number of cells corresponding to the pixels, and is disposed between the polarizing plates 102A and 102B.

  Such liquid crystal display devices are known that use various driving methods depending on the arrangement of liquid crystal materials used in the liquid crystal cell. The main liquid crystal display devices that are widely used today are the twisted nematic method (TN), the super twisted nematic method (STN), the multi-alignment division type vertical alignment method (MVA), the horizontal electric field drive method (IPS), and the OCB. (Optically Compensated Bend) etc. In particular, today, those having MVA and IPS drive systems have come into widespread use.

  On the other hand, the liquid crystal display device has a problem of viewing angle dependency due to the refractive index anisotropy of the liquid crystal cell and the polarizing plate as a specific problem. This problem of viewing angle dependency is a problem that the color and contrast of an image that is visually recognized change when the liquid crystal display device is viewed from the front and when viewed from an oblique direction. Such a problem of viewing angle characteristics has become more serious as the liquid crystal display device has recently been enlarged.

  Various techniques have been developed so far to improve the viewing angle dependency problem. As a typical method, there is a method using a retardation film. In the method using this retardation film, for example, as shown in FIG. 9, a retardation film 103 having predetermined optical characteristics is arranged between the liquid crystal cell 101 and the polarizing plates 102A and 102B, thereby depending on the viewing angle. It is a way to improve sex problems. Since such a method can improve the problem of viewing angle dependency only by incorporating a retardation film in a liquid crystal display device, it is widely used as a method that can easily obtain a liquid crystal display device having excellent viewing angle characteristics. Has come to be.

  However, since the color filter used in the liquid crystal display device has a different phase difference depending on the colored layer of each color, when the above-described retardation film is used, the difference in the phase difference of the colored layer of each color cannot be compensated. There is a problem. Specifically, when the thickness direction of the colored layer of each color is different, there is a problem that coloring is observed during black display when viewed from an oblique direction. In particular, in a high-contrast liquid crystal display device, coloring in black display when viewed from an oblique direction appears significantly. Thus, it has been difficult to completely solve the problem of viewing angle dependency.

  Although the above description relates to a liquid crystal display device, problems similar to those of a liquid crystal display device also occur in a display device having a color filter or a retardation layer used in an organic EL display device, for example.

  As a method for solving the above problem, a method is disclosed in which a retardation layer having an optimum retardation is formed according to the colored layer of each color of a color filter (see, for example, Patent Document 1). However, in this method, there is a problem in that the steps are complicated and the cost increases because it is necessary to form a retardation layer on the colored layer of each color.

  Therefore, in order to suppress coloring at the time of black display when viewed from an oblique direction, there has been proposed a color filter in which the magnitude relationship of the phase difference in the thickness direction of the colored layer of each color is defined (for example, see Patent Document 2). ). There has also been proposed a method in which a colored layer of at least one color is formed using a composition containing a retardation adjusting agent, and the thickness direction of the colored layer of each color is controlled (see, for example, Patent Document 3). ).

JP 2007-279448 A JP 2008-152140 A JP 2008-185984 A

  The present invention has been made in view of the above circumstances, and a method for producing a curable resin composition for a colored layer capable of controlling retardation in the thickness direction of the colored layer, a method for producing a color filter, and a colored layer It is a main object to provide a curable resin composition for use.

  In order to achieve the above object, the present invention provides a method for producing a curable resin composition for a colored layer, which comprises producing a curable resin composition for a colored layer containing at least a colorant and a dispersant. When the colored layer is formed using the curable resin composition, the retardation in the thickness direction of the colored layer (hereinafter, “thickness direction retardation” may be referred to as “Rth”) may be controlled. Therefore, the manufacturing method of the curable resin composition for colored layers characterized by adjusting the glass transition temperature (Tg) of the said dispersing agent is provided.

  In the present invention, when the colored layer is formed using the curable resin composition for a colored layer obtained by the method for producing the curable resin composition for a colored layer of the present invention by adjusting the Tg of the dispersant. Can obtain a colored layer having a desired Rth.

  In the said invention, it is preferable that the glass transition temperature (Tg) of the said dispersing agent exists in the range of 40 to 250 degreeC. In this case, in order to increase the absolute value of the retardation in the thickness direction of the colored layer (hereinafter, the “absolute value of retardation in the thickness direction” may be referred to as “| Rth |”), the dispersant is used. The glass transition temperature (Tg) is preferably in the range of 100 ° C to 250 ° C. When the colored layer is formed using the curable resin composition for a colored layer obtained by the method for producing a curable resin composition for a colored layer of the present invention by increasing the Tg of the dispersant within the above range. In this case, a colored layer having a large | Rth | can be obtained.

  Moreover, in this invention, it is preferable that the said dispersing agent contains the monomer unit whose glass transition temperature (Tg) is 70 degrees C or less within the range of 20 mass%-40 mass%. A colored layer is formed using the curable resin composition for colored layers obtained by the manufacturing method of the curable resin composition for colored layers of this invention because a dispersing agent contains the monomer unit whose Tg is 70 degrees C or less. This is because the fluidity in the vicinity of the colorant increases and the colorant is easily oriented.

  Furthermore, in this invention, the said dispersing agent contains the monomer unit which has an ester structure which has a saturated hydrocarbon group in a side chain, and carbon number n of the said saturated hydrocarbon group is in the range of 1-9. preferable. When forming a colored layer using the curable resin composition for a colored layer obtained by the method for producing a curable resin composition for a colored layer of the present invention, the saturated hydrocarbon group of the dispersant is present in the vicinity of the colorant. This is because, since the orientation of the colorant is not hindered, | Rth | of the colored layer can be increased.

  The present invention is also a method for producing a color filter having a colored layer forming step of forming a colored layer on a transparent substrate using a curable resin composition for a colored layer containing at least a colorant and a dispersant, Provided is a method for producing a color filter, wherein Rth of the colored layer is controlled by adjusting a glass transition temperature (Tg) of the dispersant.

  In the present invention, since the Rth of the colored layer can be controlled, a high-quality color filter can be produced.

  In the said invention, it is preferable that the glass transition temperature (Tg) of the said dispersing agent exists in the range of 40 to 250 degreeC. In this case, in order to increase | Rth | of the colored layer, it is preferable that the glass transition temperature (Tg) of the dispersant is in the range of 100 ° C to 250 ° C. By relatively increasing the Tg of the dispersant within the above range, | Rth | which the colored layer has can be increased.

  Moreover, in this invention, it is preferable that the said dispersing agent contains the monomer unit whose glass transition temperature (Tg) is 70 degrees C or less within the range of 20 mass%-40 mass%. This is because when the dispersant contains a monomer unit having a Tg of 70 ° C. or less, the fluidity in the vicinity of the colorant is increased and the colorant is easily oriented.

  Furthermore, in this invention, the said dispersing agent contains the monomer unit which has an ester structure which has a saturated hydrocarbon group in a side chain, and carbon number n of the said saturated hydrocarbon group is in the range of 1-9. preferable. This is because if the saturated hydrocarbon group of the dispersant is present in the vicinity of the colorant, the orientation of the colorant is not inhibited, and | Rth | of the colored layer can be increased.

  Further, the present invention is a curable resin composition for a colored layer containing at least a colorant and a dispersant, wherein the dispersant has a glass transition temperature (Tg) in the range of 100 ° C. to 250 ° C., and the dispersion The agent contains a monomer unit having a glass transition temperature (Tg) of 70 ° C. or less within a range of 20% by mass to 40% by mass, and provides a curable resin composition for a colored layer.

  When a colored layer is formed using the curable resin composition for a colored layer of the present invention, a colored layer having a large | Rth | can be obtained.

  In the said invention, it is preferable that the said dispersing agent contains the monomer unit which has an ester structure which has a saturated hydrocarbon group in a side chain, and carbon number n of the said saturated hydrocarbon group exists in the range of 1-9. . When forming a colored layer using the curable resin composition for a colored layer of the present invention, the presence of the saturated hydrocarbon group of the dispersant in the vicinity of the colorant does not hinder the orientation of the colorant. This is because | Rth | can be increased.

  In the present invention, the Rth of the colored layer can be controlled by adjusting the Tg of the dispersant. Therefore, in the display device using the color filter manufactured according to the present invention, even when observed from an oblique direction, Coloring at the time of display can be suppressed and good display can be performed, and further, the contrast when viewed from an oblique direction can be improved.

It is a graph which shows an example of distribution of Rth which the colored layer of each color in the color filter of this invention has. It is a graph which shows the other example of distribution of Rth which the colored layer of each color in the color filter of this invention has. It is a graph which shows the other example of distribution of Rth which the colored layer of each color in the color filter of this invention has. It is a graph which shows the other example of distribution of Rth which the colored layer of each color in the color filter of this invention has. It is a graph which shows the other example of distribution of Rth which the colored layer of each color in the color filter of this invention has. It is a schematic sectional drawing which shows an example of the color filter of this invention. It is a schematic sectional drawing which shows the other example of the color filter of this invention. It is the schematic which shows an example of a common liquid crystal display device. It is the schematic which shows an example of the liquid crystal display device which has a phase difference film.

  Hereinafter, a method for producing a curable resin composition for a colored layer, a method for producing a color filter, a curable resin composition for a colored layer, and a color filter and a display device according to the present invention will be described in detail.

A. Manufacturing method of curable resin composition for colored layers First, the manufacturing method of the curable resin composition for colored layers of this invention is demonstrated.
The manufacturing method of the curable resin composition for colored layers of this invention is a manufacturing method of the curable resin composition for colored layers which manufactures the curable resin composition for colored layers containing a coloring agent and a dispersing agent at least, The glass transition temperature (Tg) of the dispersant is adjusted in order to control the Rth of the colored layer when the colored layer is formed using the curable resin composition for the colored layer. Is.

  For example, the colored layer uses a curable resin composition for a colored layer containing at least a colorant and a dispersant to form a film made of the curable resin composition for a colored layer on a transparent substrate, and is subjected to pattern exposure. It is formed by developing and baking, and in the process of forming such a colored layer, the film expands or contracts due to temperature changes. The internal stress of the film changes depending on the degree of expansion / contraction of the film due to a temperature change in the process of forming such a colored layer. And when the internal stress of a film | membrane changes, the anisotropy of a film | membrane changes and Rth which a colored layer has also changes.

  Therefore, the present inventors paid attention to the Tg of the dispersant. A colored layer was formed using a curable resin composition for a colored layer in which the Tg of the dispersant was changed, and the Rth of the colored layer was measured. As the Tg of the dispersant was increased, the | Rth | I found out that That is, it has been found that the Rth of the colored layer can be controlled by adjusting the Tg of the dispersant contained in the curable resin composition for the colored layer.

  The reason why the Rth of the colored layer changes depending on the Tg of the dispersant contained in the curable resin composition for the colored layer is not clear, but is considered as follows. That is, at high temperatures in the process of forming the colored layer, the higher the Tg of the dispersant, the higher the viscosity of the dispersant. As a result, the colorant tends to be oriented or aggregated by the stress during expansion / contraction of the film, so that the anisotropy of the film is increased, and it is assumed that | Rth | of the finally obtained colored layer is increased. In particular, when the binder polymer or monomer is oriented due to the stress during expansion or contraction of the film during the formation of the colored layer, the colorant is oriented or aggregated, and the orientation state or aggregated state of this colorant is anisotropic to the film. It is thought that it contributes to sex.

  Thus, in this invention, Rth of a colored layer can be controlled by adjusting Tg of the dispersing agent contained in the curable resin composition for colored layers. For example, when | Rth | of the colored layer is smaller than a desired value, | Rth | of the colored layer is increased by increasing the Tg of the dispersant contained in the curable resin composition for the colored layer. Can do. On the other hand, when | Rth | of the colored layer is larger than a desired value, | Rth | of the colored layer is decreased by lowering the Tg of the dispersant contained in the curable resin composition for the colored layer. Can do.

  Accordingly, the Rth of the colored layer can be controlled by adjusting the Tg of the dispersant contained in the curable resin composition for the colored layer. Therefore, according to the method for producing the curable resin composition for the colored layer of the present invention. By using the resulting curable resin composition for a colored layer, a color filter capable of suppressing the coloring at the time of black display and performing good display even when observed from an oblique direction when applied to a display device Can be obtained. Furthermore, it is possible to obtain a color filter that can improve contrast when observed from an oblique direction.

In the present invention, the Rth of the colored layer includes the refractive index Nx in the fast axis direction (the direction in which the refractive index is the smallest) and the slow axis direction (the direction in which the refractive index is the largest) in the plane of the colored layer. Of the refractive index Ny, the refractive index Nz in the thickness direction, and the thickness d (nm) of the colored layer,
Rth = {(Nx + Ny) / 2−Nz} × d
It is a value represented by the formula of
Rth of the colored layer is a value measured using a retardation layer measuring apparatus (Axoscan ^™ Mueller Matrix Polarimeter manufactured by AXOMETRICS). In the case of a colored layer of three colors of red, green, and blue, values measured for three wavelengths of 620 nm (assuming a red colored layer), 550 nm (assuming a green colored layer), and 450 nm (assuming a blue colored layer) are used. Shall.

  Hereinafter, the composition of the colored layer curable resin composition in the method for producing the colored layer curable resin composition of the present invention and the preparation method of the colored layer curable resin composition will be described.

1. Composition of curable resin composition for colored layer The curable resin composition for colored layer used in the present invention contains at least a colorant and a dispersant, and usually further contains a binder polymer, a monomer, and a solvent. Is.
Hereinafter, each component of the curable resin composition for colored layers will be described.

(1) Colorant As the colorant, pigments and dyes are used.
Examples of the colorant used in the curable resin composition for a red colored layer include perylene pigments, lake pigments, azo pigments, quinacridone pigments, anthraquinone pigments, anthracene pigments, isoindoline pigments, and the like. . These colorants may be used alone or in combination of two or more.
Examples of the colorant used in the curable resin composition for a green colored layer include phthalocyanine pigments such as halogen polysubstituted phthalocyanine pigments or halogen polysubstituted copper phthalocyanine pigments, isoindoline pigments, and triphenylmethane basic pigments. Examples thereof include dyes and isoindolinone pigments. These colorants may be used alone or in combination of two or more.
Examples of the colorant used in the curable resin composition for the blue colored layer include copper phthalocyanine pigments, anthraquinone pigments, indanthrene pigments, indophenol pigments, cyanine pigments, dioxazine pigments, and the like. . These colorants may be used alone or in combination of two or more.

(2) Dispersant The dispersant is blended in the curable resin composition for the colored layer in order to disperse the colorant satisfactorily, and is used when the colorant is dispersed.
As described later, the dispersant is not particularly limited as long as it has a desired Tg, and is appropriately selected according to the type of the colorant. The dispersing agent used for a resin composition can be used. As the dispersant, for example, cationic, anionic, nonionic, amphoteric, silicone-based, fluorine-based surfactants, and the like can be used. Among these surfactants, a polymer surfactant (polymer dispersant) is preferable.

  Specific examples of the polymer surfactant include amides such as nonanamide, decanamide, dodecanamide, N-dodecylhexadecanamide, N-octadecylpropioamide, N, N-dimethyldodecanamide and N, N-dihexylacetamide. Compounds, amine compounds such as diethylamine, diheptylamine, dibutylhexadecylamine, N, N, N ′, N′-tetramethylmethanamine, triethylamine, tributylamine and trioctylamine, monoethanolamine, diethanolamine, triethanolamine N, N, N ′, N ′-(tetrahydroxyethyl) -1,2-diaminoethane, N, N, N′-tri (hydroxyethyl) -1,2-diaminoethane, N, N, N ′ , N'-Tetra (hydroxyethylpolyoxyethylene) -1,2-diaminoethane, 1,4-bis (2-hydroxyethyl) piperazine, amines having a hydroxy group such as 1- (2-hydroxyethyl) piperazine, etc. can be exemplified, and in addition, nipecotamide, isonipecotamide And compounds such as nicotinic acid amide.

  Furthermore, as the polymer surfactant, (co) polymers of unsaturated carboxylic acid esters such as polyacrylic acid esters; (partial) phosphoric acids of (co) polymers of unsaturated carboxylic acid such as polyacrylic acid Salts, (partial) amine salts, (partial) ammonium salts and (partial) alkylamine salts; (co) polymers of hydroxyl group-containing unsaturated carboxylic acid esters such as hydroxyl group-containing polyacrylates and their modified products; polyurethanes Unsaturated amides; polysiloxanes; long-chain polyaminoamide phosphates; amides obtained by the reaction of poly (lower alkyleneimines) with free carboxyl group-containing polyesters and salts thereof.

  Among them, polymer surfactants include (co) polymers of unsaturated carboxylic acid esters such as polyacrylic acid esters; (partial) phosphates of (co) polymers of unsaturated carboxylic acid such as polyacrylic acid , (Partial) amine salts, (partial) ammonium salts and (partial) alkylamine salts; (co) polymers of hydroxyl group-containing unsaturated carboxylic acid esters such as hydroxyl group-containing polyacrylic acid esters and their modified products; polyurethanes; Unsaturated polyamides; polysiloxanes; long-chain polyaminoamide phosphates; amides obtained by the reaction of poly (lower alkyleneimines) with free carboxyl group-containing polyesters and salts thereof are preferred. This is because these polymer surfactants are dispersants that can utilize steric hindrance and acid-base adsorption effective for dispersion in a non-aqueous system (solvent system).

  In particular, the polymer surfactant is preferably a polymer containing a repeating unit derived from dimethylaminoethyl (meth) acrylate and / or a quaternary ammonium salt thereof. Examples of the polymer include n-butyl (meth) acrylate, methyl (meth) acrylate, benzyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and γ-butyrolactone modified product of (meth) acrylic acid. Copolymers with other (meth) acrylic acid esters are preferably used, and among them, block copolymers are preferably used.

  Further, as a commercially available dispersant, Disperbyk-101, -116, -130, -140, -160, -161, -162, -163, -164, -166, and- 167, same-168, same-170, same-171, same-174, same-182, same-2000, same-2001, same--2050 (above as the Big Chemie Japan Co., Ltd. product), EFKA-4046, same. -4047 (above, manufactured by EFAK CHEMICALS), Solsperse 12000, 13240, 13940, 17000, 20000, 24000GR, 24000SC, 27000, 28000, 32000, 33500, 33500, 35200, 37500 (above, manufactured by Nihon Lubrizol Co., Ltd.), Azisper PB711, 21, the same 822 (manufactured by Ajinomoto Fine-Techno Co., Ltd.), and the like.

  In the present invention, the Tg of the dispersant is not particularly limited, and is appropriately adjusted according to the Rth of the target colored layer. For example, when it is desired to increase | Rth | of the colored layer, the Tg of the dispersant may be increased. On the other hand, when it is desired to reduce the | Rth | of the colored layer, the Tg of the dispersant may be reduced.

  The Tg of the dispersant is preferably in the range of 40 ° C to 250 ° C. Specifically, when it is desired to increase | Rth | of the colored layer, the Tg of the dispersant is preferably in the range of 100 ° C. or higher and 250 ° C. or lower, more preferably in the range of 150 ° C. to 250 ° C., and still more preferably. Is in the range of 170 ° C to 250 ° C. On the other hand, when it is desired to reduce | Rth | of the colored layer, the Tg of the dispersant is preferably in the range of 40 ° C. or higher and lower than 100 ° C., more preferably in the range of 40 ° C. to 80 ° C., and still more preferably It is within the range of 40 ° C to 60 ° C.

  The Tg of the dispersant is measured, for example, by increasing the temperature of the dispersant from room temperature to 250 ° C. at a rate of temperature increase of 10 ° C./min using a suggested scanning calorimeter (DSC-60, manufactured by Shimadzu Corporation). can do.

  Moreover, it is preferable that a dispersing agent has a monomer unit whose Tg is 70 degrees C or less. A colored layer is formed using the curable resin composition for colored layers obtained by the manufacturing method of the curable resin composition for colored layers of this invention because a dispersing agent contains the monomer unit whose Tg is 70 degrees C or less. This is because the fluidity in the vicinity of the colorant increases and the colorant is easily oriented.

  Tg of the monomer unit is 70 ° C. or less, more preferably in the range of 10 ° C. to 50 ° C., and still more preferably in the range of 10 ° C. to 30 ° C. When the Tg of the dispersant is too high, when the colored layer is formed using the curable resin composition for a colored layer obtained by the method for producing a curable resin composition for a colored layer of the present invention, the flow in the vicinity of the colorant This is because the sex is lowered. Moreover, it is because dispersion stability will deteriorate when Tg of a dispersing agent is too low.

  As such a monomer unit, those having an ester structure having a saturated hydrocarbon group in the side chain are preferably used. It is preferable that carbon number n of the said saturated hydrocarbon group exists in the range of 1-9. When forming a colored layer using the curable resin composition for a colored layer obtained by the method for producing a curable resin composition for a colored layer of the present invention, the saturated hydrocarbon group of the dispersant is present in the vicinity of the colorant. This is because, since the orientation of the colorant is not hindered, | Rth | of the colored layer can be increased.

  The content of the monomer unit in the dispersant is preferably in the range of 20% by mass to 40% by mass.

  Moreover, it is preferable that a dispersing agent has ionic sites, such as a salt. By introducing an ionic site into the molecule, it is considered that the intermolecular interaction can be increased and Tg can be increased. In this case, an ionic site can be introduced by neutralizing a part of the basic site or acidic site contained in the dispersant to form a salt.

The molecular weight of the dispersant is not particularly limited, and the weight average molecular weight of the dispersant can be about 5,000 to 50,000 in terms of polystyrene.
The weight average molecular weight can be measured, for example, by gel permeation chromatography (GPC).

  Further, the Tg of the dispersant can be adjusted by appropriately adjusting the structure of the dispersant (main chain, side chain, constituent unit, constituent unit arrangement, terminal functional group, etc.).

  Content of the dispersing agent in the curable resin composition for colored layers is in the range of 5 to 80 parts by weight with respect to 100 parts by weight of the colorant contained in the curable resin composition for colored layers. Is preferable, more preferably in the range of 10 parts by weight to 70 parts by weight, and still more preferably in the range of 11 parts by weight to 65 parts by weight.

(3) Binder polymer As a binder polymer, what is used for the general curable resin composition for colored layers is applicable.
The binder polymer may be polymerizable or may not be polymerizable. Examples of the binder polymer include ethylene-vinyl acetate copolymer, ethylene-vinyl chloride copolymer, ethylene vinyl copolymer, polystyrene, acrylonitrile-styrene copolymer, ABS resin, polymethacrylic acid resin, ethylene methacrylic acid resin. , Polyvinyl chloride resin, chlorinated vinyl chloride, polyvinyl alcohol, polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polyvinyl acetal, polyether ether ketone, polyether sulfone, polyphenylene sulfide, polyarylate, polyvinyl butyral, epoxy resin, phenoxy resin , Polyimide resin, polyamideimide resin, polyamic acid resin, polyetherimide resin, phenol resin, urea resin and the like. As the binder polymer, polymerizable monomers such as methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, sec-butyl (meth) acrylate, isobutyl (meth) ) Acrylate, tert-butyl (meth) acrylate, n-pentyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, n-decyl (meth) acrylate , Styrene, α-methylstyrene, N-vinyl-2-pyrrolidone, glycidyl (meth) acrylate, cyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentanyloxyethyl (meth) acrylate , One or more of phenyl (meth) acrylate and benzyl (meth) acrylate and a dimer of acrylic acid, methacrylic acid and acrylic acid (for example, M-5600 manufactured by Toa Gosei Chemical Co., Ltd.), itaconic acid, crotonic acid , Polymers or copolymers composed of one or more of maleic acid, fumaric acid, vinyl acetic acid, and acid anhydrides thereof. Furthermore, the polymer etc. which added the ethylenically unsaturated compound which has a glycidyl group or a hydroxyl group to said copolymer are mentioned. Said binder polymer is an example and is not limited to these.

  Among the above binder polymers, from the viewpoint of compatibility with the monomer used in combination, polymethyl methacrylate resin, polyethyl methacrylate resin, polymethyl methacrylate resin and polyethyl methacrylate resin copolymer, Phenoxy resin, epoxy resin, polycarbonate resin, polystyrene resin, ethyl hydroxyethyl cellulose, cellulose triacetate and the like can be preferably used. Particularly preferably, polymethyl methacrylate resin, polyethyl methacrylate resin, polystyrene resin, methacrylic acid and styrene, glycidyl (meth) acrylate, cyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, benzyl (meth) acrylate These two or more types of copolymers, phenoxy resins, epoxy resins, and modified products thereof can be used.

(4) Monomer As the monomer, those used in general curable resin compositions for colored layers can be applied.
The monomer is not particularly limited as long as it can be polymerized, but a monomer that can be polymerized by a photopolymerization reaction is preferably used. Examples of such monomers include allyl (meth) acrylate, benzyl (meth) acrylate, butoxyethyl (meth) acrylate, butoxyethylene glycol (meth) acrylate, cyclohexyl (meth) acrylate, and dicyclopentanyl (meth) acrylate. , 2-ethylhexyl (meth) acrylate, glycerol (meth) acrylate, glycidyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, isobornyl (meth) acrylate, isodexyl (meth) acrylate , Isooctyl (meth) acrylate, lauryl (meth) acrylate, 2-methoxyethyl (meth) acrylate, methoxyethylene glycol (meth) acrylate, Noxyethyl (meth) acrylate, stearyl (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,5-pentanediol di (meth) acrylate 1,6-hexanediol di (meth) acrylate, 1,3-propanediol (meth) acrylate, 1,4-cyclohexanediol di (meth) acrylate, 2,2-dimethylolpropane di (meth) acrylate, glycerol Di (meth) acrylate, tripropylene glycol di (meth) acrylate, glycerol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, polyoxyethylated trimethylolpropane tri (meth) ) Acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, triethylene glycol di (meth) acrylate, polyoxypropyltrimethylolpropane tri (meth) acrylate, butylene glycol di (meth) acrylate, 1, 2,4-butanetriol tri (meth) acrylate, 2,2,4-trimethyl-1,3-pentanediol di (meth) acrylate, diallyl fumarate, 1,10-decanediol dimethyl (meth) acrylate, dipenta Erythritol hexa (meth) acrylate, γ-methacryloxypropyltrimethoxysilane, 1-vinyl-2-pyrrolidone, 2-hydroxyethylacryloyl phosphate, tetrahydrofurfuryl (meth) Chryrate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, 3-butanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, hydroxypivalic acid Ester neopentyl glycol di (meth) acrylate, phenol-ethylene oxide modified (meth) acrylate, phenol-propylene oxide modified (meth) acrylate, N-vinyl-2-pyrrolidone, bisphenol A-ethylene oxide modified di (meth) acrylate, Pentaerythritol di (meth) acrylate monostearate, tetraethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate Rate, trimethylolpropane propylene oxide modified tri (meth) acrylate, isocyanuric acid ethylene oxide modified tri (meth) acrylate, trimethylolpropane ethylene oxide modified tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipenta Erythritol hexa (meth) acrylate, pentaerythritol tetra (meth) acrylate, urethane (meth) acrylate oligomer in which (meth) acrylate group is bonded to oligomer having polyurethane structure, (meth) acrylate group is bonded to oligomer having polyester structure Polyester (meth) acrylate oligomer and epoxy (meth) acrylate in which (meth) acrylate group is bonded to epoxy group-containing oligomer Examples thereof include a acrylate oligomer, a polyurethane (meth) acrylate having a (meth) acrylate group, a polyester (meth) acrylate having a (meth) acrylate group, and an epoxy (meth) acrylate resin having a (meth) acrylate group.
In addition, (meth) acrylate means that it is either an acrylate group or a methacrylate group.

(5) Solvent The curable resin composition for the colored layer may contain a solvent. As a solvent, what is used for the general curable resin composition for colored layers is applicable.

(6) Other components The curable resin composition for the colored layer comprises a polymerization initiator, a sensitizer, an antioxidant, a coating property improver, a development improver, a crosslinking agent, a polymerization inhibitor, and a plastic as necessary. An agent, a flame retardant, etc. may be contained.

2. Preparation method of curable resin composition for colored layer In the present invention, in order to control the Rth of the colored layer when the colored layer is formed using the curable resin composition for the colored layer, the glass transition of the dispersant The temperature (Tg) is adjusted to prepare a curable resin composition for a colored layer.
For example, the Tg of the dispersant can be adjusted by appropriately selecting the molecular weight and structure of the dispersant (main chain, side chain, constituent unit, constituent unit sequence, terminal functional group, etc.). Specifically, the Tg of the dispersant tends to increase by introducing a monomer unit having a relatively large Tg into the dispersant or by introducing an ionic site such as a salt into the dispersant.

B. Next, a method for producing a color filter of the present invention will be described.
In the method for producing a color filter of the present invention, a color filter having a colored layer forming step of forming a colored layer on a transparent substrate using a curable resin composition for a colored layer containing at least a colorant and a dispersant. In the production method, Rth of the colored layer is controlled by adjusting the glass transition temperature (Tg) of the dispersant.

  In the present invention, as described above, the Rth of the colored layer can be controlled by adjusting the Tg of the dispersant contained in the curable resin composition for the colored layer. Therefore, in the display device using the color filter manufactured according to the present invention, even when observed from an oblique direction, coloring during black display is suppressed and good display can be performed. Furthermore, it is possible to improve the contrast when observed from an oblique direction.

When a color filter is used for a display device, the state where the display device does not have a color filter (hereinafter, “the state where the display device does not have a color filter” may be referred to as “a display device without a color filter”). Depending on the configuration, the display device without the color filter may exhibit wavelength dependency. As the wavelength dependency, for example, the reverse dispersion type wavelength dependency in which Rth on the short wavelength side is smaller than Rth on the long wavelength side, or the positive dispersion type in which Rth on the short wavelength side is larger than Rth on the long wavelength side The wavelength dependence is mentioned. In some cases, the Rth of the display device without a color filter is a flat type having no wavelength dependency. Further, when the display device without a color filter includes a member exhibiting a wavelength dependency of normal dispersion type and a member exhibiting a wavelength dependency of reverse dispersion type, the wavelength dependency of the display device without the color filter as a whole May be radial.
In addition, the sign of Rth of the display device without a color filter is not only positive or negative in the entire use wavelength region, but may also be positive and negative.

For example, when a display device without a color filter exhibits reverse dispersion wavelength dependence, the Rth on the short wavelength side is smaller than the Rth on the long wavelength side, so the Rth of the colored layer of the color on the short wavelength side is long. By controlling the Rth of the colored layer of each color so as to be larger than the Rth of the colored layer of the color on the wavelength side, the Rth of the display device without the color filter can be offset.
FIG. 1 is a graph showing an example of Rth distribution of colored layers of three colors of red, green, and blue, and a color filter unmounted display device showing Rth of colored layers of each color and wavelength dispersion of inverse dispersion type This shows a case where the Rth of the current is offset. In the example shown in FIG. 1, the display device without a color filter has Rth of +30 nm in the red light region, +25 nm in the green light region, and +20 nm in the blue light region. In this case, in the color filter, each color is colored so that Rth of the red colored layer (R) is −30 nm, Rth of the green colored layer (G) is −25 nm, and Rth of the blue colored layer (B) is −20 nm. By controlling the Rth of the layer, the Rth of the display device without the color filter can be offset. That is, in this case, for the colored layer, Rth of the red colored layer (R) is −30 nm, Rth of the green colored layer (G) is −25 nm, and Rth of the blue colored layer (B) is −20 nm. The Tg of the dispersant contained in the curable resin composition is adjusted.

Further, for example, when a display device without a color filter exhibits positive dispersion wavelength dependency, Rth on the short wavelength side is larger than Rth on the long wavelength side, so that the Rth of the colored layer of the short wavelength side is By controlling the Rth of the colored layer of each color so as to be smaller than the Rth of the colored layer of the color on the long wavelength side, the Rth of the display device without the color filter can be offset.
FIG. 2 is a graph showing an example of Rth distribution of the colored layers of three colors of red, green, and blue. The color filter non-mounted display device showing the Rth of the colored layers of each color and the wavelength dependence of the positive dispersion type This shows a case where the Rth of the current is offset. In the example shown in FIG. 2, the display device without a color filter has Rth of +20 nm in the red light region, +23 nm in the green light region, and +30 nm in the blue light region. In this case, in the color filter, each color is colored so that Rth of the red colored layer (R) is −20 nm, Rth of the green colored layer (G) is −23 nm, and Rth of the blue colored layer (B) is −30 nm. By controlling the Rth of the layer, the Rth of the display device without the color filter can be offset. That is, in this case, the red colored layer (R) has an Rth of −20 nm, the green colored layer (G) has an Rth of −23 nm, and the blue colored layer (B) has an Rth of −30 nm. The Tg of the dispersant contained in the curable resin composition is adjusted.

Further, for example, when the display device without a color filter is a flat type that does not have wavelength dependence, Rth is constant. Therefore, the color filter is controlled by controlling the Rth of the colored layers of each color to be uniform. The Rth of the unmounted display device can be offset.
FIG. 3 is a graph showing an example of the Rth distribution of the colored layers of three colors of red, green, and blue. The flat color filter unmounted display device that does not show the wavelength dependency of the Rth of the colored layers of each color This shows a case where the Rth of the current is offset. In the example shown in FIG. 3, the display device without a color filter does not exhibit wavelength dispersion, and has Rth of +30 nm in the red light region, the green light region, and the blue light region. In this case, in the color filter, Rth of the colored layer of each color is set so that Rth of the red colored layer (R), Rth of the green colored layer (G), and Rth of the blue colored layer (B) are -30 nm, respectively. By controlling, Rth of the display device without the color filter can be offset. That is, in this case, the curable resin composition for the colored layer is such that Rth of the red colored layer (R), Rth of the green colored layer (G), and Rth of the blue colored layer (B) are each -30 nm. The Tg of the dispersant contained in the product is adjusted.

  Thus, when the Rth of the color filter and the Rth of the display device without the color filter are offset, the contrast when observed from an oblique direction can be improved. By canceling Rth of the color filter and Rth of the display device without the color filter, | Rth | of the entire display device using the color filter can be made small, so that the intensity of leaked light is reduced. The contrast when observed from an oblique direction can be improved.

  Hereinafter, the Rth and the colored layer forming step of the colored layer in the method for producing a color filter of the present invention will be described.

1. Rth of colored layer
In the present invention, the Rth of the colored layer is controlled by adjusting the Tg of the dispersant contained in the curable resin composition for the colored layer.

  In the present invention, the Rth of the target colored layer is not particularly limited. For example, when a color filter is used for a display device, the Rth of the color filter and the Rth of the display device without the color filter are calculated. The Rth of the colored layer of each color may be controlled so as to be offset, and the Rth of the colored layer of each color may be controlled so that the Rth of the colored layer of each color is uniform.

  When the Rth of the color filter and the Rth of the display device without the color filter cancel each other, as described above, the contrast when observed from an oblique direction can be improved. By canceling Rth of the color filter and Rth of the display device without the color filter, | Rth | of the entire display device using the color filter can be made small, so that the intensity of leaked light is reduced. The contrast when observed from an oblique direction can be improved.

Note that “Rth of a display device without a color filter” refers to Rth of the display device itself in a state where no color filter is attached to the display device. Such Rth can be obtained by, for example, measuring Rth for a configuration other than the color filter used in the display device, and performing simulation.
Rth of the configuration other than the color filter used in the display device is 620 nm (assuming a red colored layer), 550 nm (assuming a green colored layer), and a retardation layer measuring device (Axoscan ^TM Mueller Matrix Polarimeter manufactured by AXOMETRICS), and The values measured for three wavelengths of 450 nm (assuming a blue colored layer) shall be used.

  “The Rth of the color filter and the Rth of the display device without the color filter cancel each other” means that when the color filter is used in the display device, it is observed from an oblique direction during black display. The color in the wavelength region corresponding to the Rth of each color layer and the color layer of each color to such an extent that the contrast is improved when observed from an oblique direction without being colored black. It means that the absolute value of the difference from Rth of the display device with no filter is close to zero. Specifically, the absolute value of the Rth difference is 5 nm or less, preferably 3 nm or less, particularly preferably 1 nm or less.

  On the other hand, when the Rth of the colored layer of each color is uniform, in a display device using a color filter, even when black display is observed from an oblique direction, light leakage at a specific wavelength does not occur. It is possible to perform a good black display without any problem.

Note that “the Rth of each color layer is uniform” means that, when a color filter is used for a display device, even when the black color is observed from an oblique direction, a blackish color is displayed. This means that the Rths of the colored layers of each color are aligned to the extent that no is observed. Specifically, the absolute value of the difference between the maximum value and the minimum value of Rth included in each color layer is 5 nm or less, preferably 3 nm or less, particularly preferably 1 nm or less.
As long as the Rths of the colored layers of the respective colors are uniform, the Rths of the colored layers may be all positive or negative, or may be mixed. For example, in FIG. 4, all the Rths of the colored layers of three colors (R, G, B) show negative values, and the Rths of the colored layers of each color are uniform. In FIG. Rth of the colored layer of (R) and green (G) shows a negative value, Rth of the colored layer of blue (B) shows a positive value, and Rth of the colored layer of each color becomes uniform Yes.

  In the present invention, in order to control Rth of the colored layer, the Tg of the dispersant contained in the curable resin composition for the colored layer is adjusted. For example, the Tg of the dispersant can be adjusted by appropriately selecting the molecular weight and structure of the dispersant (main chain, side chain, constituent unit, constituent unit sequence, terminal functional group, etc.). That is, when forming a colored layer of a plurality of colors, the Tg of the dispersant contained in the curable resin composition for colored layers of each color is adjusted, specifically, the curable resin composition for colored layers of each color. The Tg of the dispersant is adjusted by changing the molecular weight and structure (main chain, side chain, constituent unit, constituent unit arrangement, terminal functional group, etc.) of the dispersant contained in A colored layer can be obtained.

  In addition, since it described in the said "A. manufacturing method of curable resin composition for colored layers" about the curable resin composition for colored layers, description here is abbreviate | omitted.

2. Colored layer forming step The colored layer forming step in the present invention is a step of forming a colored layer on a transparent substrate using a colored layer curable resin composition containing at least a colorant and a dispersant.

As a method for forming a colored layer using the curable resin composition for a colored layer, a general method for forming a colored layer can be employed. For example, the curable resin composition for a colored layer is formed on a transparent substrate. A method of forming a film, pattern exposure, developing and baking, or a method of forming and curing a film made of a curable resin composition for a colored layer on a transparent substrate by an inkjet method is used.
About the method of forming the film | membrane consisting of the curable resin composition for colored layers, the pattern exposure method, the image development method, and the baking method, it can be made to be the same as that of formation of a general colored layer.

  As the curable resin composition for a colored layer, a curable resin composition for a colored layer of three colors of red, green and blue is usually used.

  The film thickness of the colored layer varies depending on the color of the colored layer, but can be specifically set within a range of 1 μm to 5 μm.

  The colored layers of each color are regularly arranged corresponding to the pixels. The arrangement of the colored layers is not particularly limited as long as the colored layers of the respective colors are arranged on an average when viewed macroscopically, and examples thereof include a stripe arrangement, a mosaic arrangement, and a delta arrangement.

The transparent substrate used in the present invention is not particularly limited as long as it can form a colored layer and, if necessary, a light shielding part, and is transparent to visible light.
In the present invention, it is more preferable that the transparent substrate does not have Rth. Such a transparent substrate can be the same as the transparent substrate used for a general color filter.

  Specifically, a transparent rigid material having no flexibility such as quartz glass, Pyrex (registered trademark) glass, synthetic quartz plate, or a transparent flexible flexible material such as a transparent resin film or an optical resin plate. Materials and the like.

3. Other Steps The method for producing a color filter of the present invention can include a step of forming other members in addition to the colored layer forming step. For example, an overcoat layer forming step for forming an overcoat layer on a colored layer of a plurality of colors, a light shielding portion forming step for forming a light shielding portion for defining pixels on a transparent substrate, and the like can be given.

4). Use of color filter The color filter obtained by the manufacturing method of the color filter of this invention is used for a liquid crystal display device, an organic EL display device, a plasma display etc., for example. Especially, it is used suitably for a liquid crystal display device.

When used in the display device a color filter obtained by the method for producing a color filter of the present invention, in the display device, the luminance at the time of a white display state T _on, the luminance at the time of a black display state and T _off Then, the contrast represented by the ratio of T _on / T _off is preferably 500 or more, more preferably 800 or more, and particularly preferably 1000 or more. This is because when the contrast is less than the above range, the contrast is low and the display quality may be impaired.

C. Next, the curable resin composition for a colored layer of the present invention will be described.
The curable resin composition for a colored layer of the present invention is a curable resin composition for a colored layer containing at least a colorant and a dispersant, and the glass transition temperature (Tg) of the dispersant is 100 ° C to 250 ° C. And the dispersant contains a monomer unit having a glass transition temperature (Tg) of 70 ° C. or less within a range of 20% by mass to 40% by mass.

  When a colored layer is formed using the curable resin composition for a colored layer of the present invention, a colored layer having a large | Rth | can be obtained.

  In addition, since the other point of the curable resin composition for colored layers was described in detail in the above-mentioned section “A. Method for producing curable resin composition for colored layer”, description thereof is omitted here.

D. Next, the color filter of the present invention will be described.
The color filter of the present invention is a color filter having a transparent substrate and a plurality of colored layers formed on the transparent substrate and containing at least a colorant and a dispersant, and the color filter is used for a display device. The glass transition temperature (Tg) of the dispersant contained in the colored layer of each color was adjusted so that the Rth of the color filter and the Rth of the display device without the color filter were offset. It is characterized by being.

The color filter of the present invention will be described with reference to the drawings.
FIG. 6 is a schematic sectional view showing an example of the color filter of the present invention. As illustrated in FIG. 6, the color filter 10 of the present invention includes a transparent substrate 1 and a plurality of colored layers 2 formed on the transparent substrate 1 (in FIG. 6, a red colored layer 2R and a green colored layer 2G). , Blue colored layer 2B) and light shielding portion 3 formed between colored layers 2 (red colored layer 2R, green colored layer 2G, blue colored layer 2B) of each color on transparent substrate 1.

  FIG. 1 is a graph showing an example of the Rth distribution of the color filter of the present invention, in which the Rth of the color filter of the present invention and the Rth of a display device without a color filter exhibiting an inverse dispersion type wavelength dependency cancel each other. This is the case of three colored layers of red, green and blue. In the example shown in FIG. 1, the display device without a color filter has Rth of +30 nm in the red light region, +25 nm in the green light region, and +20 nm in the blue light region. In this case, in the color filter of the present invention, Rth of the red colored layer (R) is −30 nm, Rth of the green colored layer (G) is −25 nm, and Rth of the blue colored layer (B) is −20 nm. The Tg of the dispersant contained in the colored layer of each color is adjusted.

  FIG. 2 is a graph showing another example of the Rth distribution of the color filter of the present invention. The Rth of the color filter of the present invention and the Rth of the display device without a color filter exhibiting wavelength dispersion of the positive dispersion type. Is shown in the case of three colored layers of red, green and blue. In the example shown in FIG. 2, the display device without a color filter has Rth of +20 nm in the red light region, +23 nm in the green light region, and +30 nm in the blue light region. In this case, in the color filter of the present invention, Rth of the red colored layer (R) is −20 nm, Rth of the green colored layer (G) is −23 nm, and Rth of the blue colored layer (B) is −30 nm. The Tg of the dispersant contained in the colored layer of each color is adjusted.

  FIG. 3 is a graph showing another example of the Rth distribution of the color filter of the present invention. The Rth of the color filter of the present invention and the Rth of the flat color filter non-mounted display device that does not show wavelength dependency. Is shown in the case of three colored layers of red, green and blue. In the example shown in FIG. 3, the display device without a color filter does not exhibit wavelength dispersion, and has Rth of +30 nm in the red light region, the green light region, and the blue light region. In this case, in the color filter of the present invention, each color is colored so that Rth of the red colored layer (R), Rth of the green colored layer (G), and Rth of the blue colored layer (B) are -30 nm, respectively. The Tg of the dispersant contained in the layer is adjusted.

  Thus, when the Rth of the color filter and the Rth of the display device without the color filter are offset, the contrast when observed from an oblique direction can be improved. Since the Rth of the color filter and the Rth of the display device without the color filter are canceled out, | Rth | of the entire display device using the color filter of the present invention can be reduced, so that the intensity of the leaked light Thus, the contrast when observed from an oblique direction can be improved.

  FIG. 4 is a graph showing another example of the Rth distribution of the color filter of the present invention, and shows a case of three colored layers of red, green, and blue. In the example shown in FIG. 4, the Tg of the dispersant contained in the colored layer of each color so that the Rth of the red colored layer (R), the green colored layer (G), and the blue colored layer (B) are uniform. Has been adjusted.

Usually, the Rth of the colored layer of each color is often different, and the retardation layer used in the display device does not compensate for the Rth of the colored layer of each color, so depending on the color filter, the black display is observed from an oblique direction. In this case, there is a problem that a blackish color is observed due to leakage light at a specific wavelength.
On the other hand, when the Rths of the colored layers of each color are uniform, leakage light at a specific wavelength occurs even when black display is observed from an oblique direction in the display device using the color filter of the present invention. Therefore, good black display without coloring can be performed.

  The transparent substrate and application are the same as those described in the above section “B. Color filter manufacturing method”, and thus the description thereof is omitted here. Hereinafter, another configuration of the color filter of the present invention will be described.

(1) Colored layer The colored layers of a plurality of colors used in the present invention are formed on a transparent substrate and contain at least a colorant and a dispersant. In addition, when the color filter is used for the display device, the Tg of the dispersant contained in the colored layer of each color is adjusted so that the Rth of the color filter and the Rth of the display device without the color filter are offset. It is a thing. As the multi-colored colored layer, usually three colored layers of red, green and blue are used.

  In the present invention, as described above, since the Rth of the colored layer can be controlled by adjusting the Tg of the dispersant contained in the colored layer, the Tg of the dispersant contained in the colored layer of each color is adjusted. Thus, the Rth of the color filter and the Rth of the display device without the color filter can be offset.

In general, when a plurality of colored layers are formed using the same dispersant, the Rth of each color layer varies depending on the type of the colorant, the dispersion state, and the like. Therefore, for example, when adjusting the Tg of the dispersant contained in the colored layer of each color so that Rth of the colored layer of each color has a desired value as shown in FIGS. Thus, the Tg of the dispersant contained in the colored layer of each color is varied so that the Rth of the colorant has a desired value. That is, when the Tg of the dispersant contained in the colored layer of each color is adjusted so that the Rth that the color filter has and the Rth of the display device without the color filter are offset, the Rth that the color filter has The Tg of the dispersant contained in the colored layer of each color is different so that the Rth of the display device without the color filter is offset.
In addition, in the case where the Tg of the dispersant contained in the colored layer of each color is different so that the Rth of the color filter and the Rth of the display device without the color filter are offset, among the colored layers of a plurality of colors, The Tg of the dispersant contained in one or more colored layers may be different from the Tg of the dispersant contained in other colored layers.

  The colorant, dispersant, binder polymer, monomer and the like contained in the colored layer are described in the above section “A. Method for producing curable resin composition for colored layer”. Since the formation method and the thickness of the colored layer are described in the above-mentioned section “B. Manufacturing method of color filter”, description thereof is omitted here.

(2) Other member The color filter of this invention may have another member as needed other than said colored layer and transparent substrate. For example, a shading part etc. are mentioned.

  The light-shielding portion used in the present invention is formed on the transparent substrate and defines pixels. Such a light-shielding portion can be the same as a general light-shielding portion, and therefore the description thereof is omitted here.

E. Display Device Next, the display device of the present invention will be described.
The display device of the present invention is a display device comprising a color filter having a transparent substrate and a plurality of colored layers formed on the transparent substrate and containing at least a colorant and a dispersant. The glass transition temperature (Tg) of the dispersant contained in the colored layer of each color is adjusted so that the Rth of the display device and the Rth of the display device without a color filter are offset. A display device is provided.

  According to the present invention, since the color filter is formed so that the Rth of the display device without the color filter is offset, the contrast when observed from an oblique direction can be increased.

In the display device of the present invention, the luminance at the time of a white display state _{T on,} when the luminance at the time of a black display state and a _{T off,} contrast represented by a ratio of _T on _/ T _off is 500 or more, Among them, 800 or more, particularly 1000 or more is preferable. This is because when the contrast is less than the above range, the contrast is low and the display quality may be impaired.

  The color filter used in the present invention has been described in detail in the section “B. Manufacturing method of color filter”, so description thereof is omitted here.

The display device of the present invention is not particularly limited as long as it has at least the color filter described above, and appropriately includes other constituent members depending on the type of the display device.
Examples of the display device include a liquid crystal display device, an organic EL display device, a plasma display, and the like. Among these, a liquid crystal display device is preferable.
Since the liquid crystal display device, the organic EL display device, the members constituting the plasma display, and the like can be the same as those of general display devices, description thereof is omitted here.
The display device of the present invention can be used for a large display, a portable information terminal, and the like.

  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.

Hereinafter, the present invention will be specifically described with reference to examples.
[Example 1]
<Preparation of pigment dispersion>
First, each color pigment dispersion was prepared with the following composition. Each color pigment dispersion was obtained by uniformly stirring and mixing a mixture having a composition (weight ratio) shown in Table 1 and then filtering with a 1 μm filter.

The red pigment in the table is C.I. I. PR254 (manufactured by Ciba Specialty Chemicals, chromophthal DPP Red BP) was used, and the yellow pigment was C.I. I. PY139 (manufactured by BASF, Paliotor Yellow D1819) was used, and the green pigment was C.I. I. PG58 (manufactured by Dainippon Ink and Chemicals, Inc.) was used, and the blue pigment I. PB15: 6 (manufactured by BASF, Heliogen Blue L6700F) is used, and the purple pigment is C.I. I. PV23 (manufactured by Clariant, Foster Palm RL-NF) was used.
Dispersant A is a copolymer of butyl methacrylate: benzyl methacrylate: dimethylaminoethyl methacrylate = 20: 40: 40 (molar ratio), glass transition temperature (Tg) is 60 ° C., and average molecular weight is 10,000. It is. Dispersant B is obtained by adding 10.0 mol% of benzyl chloride to 100 mol% of a copolymer of cyclohexyl methacrylate: methyl methacrylate: dimethylaminoethyl methacrylate = 20: 40: 40 (molar ratio), The glass transition temperature (Tg) is 100 ° C. and the weight average molecular weight is 11,000. Dispersant C is obtained by adding 20.0 mol% of benzyl chloride to 100 mol% of a copolymer of cyclohexyl methacrylate: methyl methacrylate: methylaminoethyl methacrylate = 20: 40: 40 (molar ratio). The glass transition temperature (Tg) is 160 ° C. and the weight average molecular weight is 10,000.
As the organic solvent, propylene glycol monomethyl ether acetate was used.

<Preparation of curable resin composition for colored layer>
Subsequently, a curable resin composition for each colored layer was prepared with the following composition. The curable resin composition for each colored layer was obtained by uniformly stirring and mixing a mixture (weight ratio) shown in Table 2 and then filtering with a 1 μm filter.

  In addition, the polymer in a table | surface is 2-methacryloyl with respect to 100 mol% of copolymers of methyl acrylate: acrylic acid: 2-hydroxyethyl methacrylate = 55.0: 30.0: 15.0 (molar ratio). Oxyethyl isocyanate is added at 15.0 mol%, and the weight average molecular weight is 22,000. In addition, the monomer in the table is composed of dipentaerythritol pentaacrylate dibasic acid anhydride and dipentaerythritol hexaacrylate at a mass ratio of 3: 7 (TO1382 manufactured by Toagosei Co., Ltd.) ) Was used. As a photopolymerization initiator, 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one (manufactured by Irgagua 907 Ciba Specialty Chemicals) was used.

<Measurement of Rth of colored layer>
The curable resin composition for each colored layer shown in Table 2 was applied to a glass substrate by spin coating, and then prebaked at 80 ° C. for 3 minutes on a hot plate. Next, the substrate was cooled to room temperature and then exposed to ultraviolet rays using an ultrahigh pressure mercury lamp. Thereafter, this substrate was alkali-developed and dried, followed by post-baking in an oven at 230 ° C. for 30 minutes to obtain colored layers of each color. The thickness of the dried film was 2.0 μm. About the obtained colored layer, Rth was measured by the measuring method of Rth described above. The results are shown in Table 3.

  From the results of the green colored layer curable resin compositions (GR-1 to GR-3), it was found that the Rth of the colored layer can be controlled by adjusting the Tg of the dispersant.

[Reference example]
A light shielding part (BM) photoresist is applied to the top surface of the glass substrate that has been cleaned by pretreatment using a spin coater (Mikasa, model 1H-DX2), prebaked at 90 ° C for 3 minutes, and formed into a predetermined pattern. The mask was used to irradiate ultraviolet rays with a proximity aligner at an intensity of 75 mJ / cm ² (2 kW ultra-high pressure mercury lamp USH-2004TO, 405 nm illuminance conversion). Subsequently, 0.05% KOH aqueous solution was sprayed for 60 seconds with a developing device for solvent-type light-sensitive material (manufactured by Shibaura Kogyo Co., Ltd., VFJ0004) for development. After development, the coating film was post-baked at 230 ° C. for 30 minutes using a clean oven (manufactured by Shinobi Institute, SCOV-250 Hy-So) to form a light shielding part (BM) having a line width of 6 μm.

Subsequently, the curable resin composition for red colored layer (RR-1) was applied by a spin coater (manufactured by MIKASA, model 1H-DX2) and dried to form a coating film. This coating film was prebaked on a hot plate at 100 ° C. for 3 minutes. A mask designed to form a predetermined pattern was used to irradiate ultraviolet rays with a proximity aligner at an intensity of 75 mJ / cm ² (2 kW ultra-high pressure mercury lamp USH-2004TO, 405 nm illuminance conversion). Next, a 0.05% KOH aqueous solution was sprayed on the substrate on which the coating film was formed with a solvent-type photosensitive material developing device (VFJ0004, manufactured by Shibaura Kogyo Co., Ltd.) for 60 seconds for development. After the development, the coating film was post-baked at 230 ° C. for 30 minutes using a clean oven (manufactured by Shinobi Institute, SCOV-250 Hy-So). In this way, a red colored layer was formed.
Next, the green colored layer was similarly formed using the curable resin composition for green colored layers (GR-1). Furthermore, the blue colored layer was formed using the curable resin composition for blue colored layers (BR-1). Thereby, a color filter was obtained. The thickness of each colored layer was 2.0 μm.

A transparent common electrode made of indium tin oxide (ITO) was formed on the upper surface of the color filter.
On the other hand, thin film transistors (TFTs) were formed on a plurality of predetermined locations on a glass substrate, and transparent pixel electrodes were formed of indium tin oxide (ITO) so as to be connected to the drain electrodes of the respective TFTs, thereby producing counter electrode substrates. .
Next, a solution obtained by diluting a vertical alignment film solution (JALS-20210-R2) with γ-butyrolactone to 50% so as to cover each of the transparent common electrode surface and the transparent pixel electrode surface is applied and dried. (Thickness 0.07 μm) was formed. Next, both substrates are made to face each other so that these alignment films face each other, the space between both substrates is sealed with a sealing member, and liquid crystal (MLC-6608 manufactured by Merck Japan) is injected into the sealed space. Was sealed to prepare a liquid crystal display device.

[Example 2]
A color filter and a liquid crystal display device were produced in the same manner as in the reference example except that the curable resin composition for the green colored layer was changed from (GR-1) to (GR-2).

[Example 3]
A color filter and a liquid crystal display device were produced in the same manner as in the reference example except that the curable resin composition for the green colored layer was changed from (GR-1) to (GR-3).

[Evaluation]
First, Rth of the colored layers obtained in Reference Example and Examples 2 and 3 was measured by the above-described Rth measurement method. The results are shown in Table 4.

  Next, the liquid crystal display devices of the reference example and examples 2 and 3 were displayed in black, and the contrast and coloring in the oblique direction were evaluated. The results are shown in Table 5.

First, with respect to the contrast in the diagonal direction, the intensity of leakage light at the time of black display in an azimuth (oblique) tilted by 45 ° from the normal direction of the liquid crystal panel was measured using a luminance meter (Spectroradiometer SR-3 manufactured by Topcon). Measurements were made and each was comparatively evaluated with the leakage light intensity of the comparative example as 100. As a result, Examples 2 and 3 were 95 and 90 with respect to the leaked light (100) of the reference example, respectively, and it was confirmed that the contrast was improved.
Subsequently, the coloration in the oblique direction was evaluated by visually observing light leaking from an azimuth (oblique) inclined 45 ° from the normal direction of the liquid crystal panel during black display. As a result, in the reference example, the coloration was clearly confirmed visually when observed from an oblique direction. On the other hand, in Example 2, when it observed from the diagonal direction, the improvement was seen to such an extent that coloring could not be confirmed visually. In Example 3, even when observed from an oblique direction, the coloration could not be visually confirmed, and a good black display could be confirmed.

  From the above, as shown in Example 3, the Rth of the colored layer can be controlled by adjusting the Tg of the dispersant in the curable resin composition for the colored layer of each color, and the oblique visibility is obtained. A good liquid crystal display device could be obtained. In the color filter of the reference example, since the Tg of the dispersant was too high or too low, the Rth balance of the red colored layer, the green colored layer, and the blue colored layer was poor, and the oblique visibility was poor.

DESCRIPTION OF SYMBOLS 1 ... Transparent substrate 2 ... Colored layer 2R ... Red colored layer 2G ... Green colored layer 2B ... Blue colored layer 3 ... Light-shielding part 4 ... Overcoat layer 10 ... Color filter

Claims (10)

A method for producing a curable resin composition for a colored layer, comprising producing a curable resin composition for a colored layer containing at least a colorant and a dispersant,
Adjusting the glass transition temperature (Tg) of the dispersant in order to control the retardation in the thickness direction of the colored layer when the colored layer is formed using the curable resin composition for the colored layer. The manufacturing method of the curable resin composition for colored layers characterized by the above-mentioned.   2. The method for producing a curable resin composition for a colored layer according to claim 1, wherein the dispersant has a glass transition temperature (Tg) in the range of 40 ° C. to 250 ° C. 3.   The glass transition temperature (Tg) of the dispersant is set in the range of 100 ° C to 250 ° C in order to increase the absolute value of the retardation in the thickness direction of the colored layer. Of producing a curable resin composition for a colored layer.   The said dispersing agent contains the monomer unit whose glass transition temperature (Tg) is 70 degrees C or less in the range of 20 mass%-40 mass%, In any one of Claim 1 to 3 characterized by the above-mentioned. The manufacturing method of curable resin composition for colored layers of description.   The said dispersing agent contains the monomer unit which has an ester structure which has a saturated hydrocarbon group in a side chain, and carbon number n of the said saturated hydrocarbon group exists in the range of 1-9, The manufacturing method of the curable resin composition for colored layers in any one of Claims 1-4. A method for producing a color filter having a colored layer forming step of forming a colored layer on a transparent substrate using a curable resin composition for a colored layer containing at least a colorant and a dispersant,
A method for producing a color filter, wherein the retardation in the thickness direction of the colored layer is controlled by adjusting the glass transition temperature (Tg) of the dispersant.   The method for producing a color filter according to claim 6, wherein a glass transition temperature (Tg) of the dispersant is in a range of 40 ° C. to 250 ° C.   The glass transition temperature (Tg) of the dispersant is set in the range of 100 ° C to 250 ° C in order to increase the absolute value of the retardation in the thickness direction of the colored layer. Manufacturing method of color filter.   The said dispersing agent contains the monomer unit whose glass transition temperature (Tg) is 70 degrees C or less in the range of 20 mass%-40 mass%, In any one of Claim 6-8 characterized by the above-mentioned. The manufacturing method of the color filter of description.   The said dispersing agent contains the monomer unit which has an ester structure which has a saturated hydrocarbon group in a side chain, and carbon number n of the said saturated hydrocarbon group exists in the range of 1-9, It is characterized by the above-mentioned. A method for producing a color filter according to claim 9.

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