JP2009157328A - Color filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a color filter by which display defects, such as, an alignment defect and a flicker are hardly generated and which has high contrast of a white display part and a black display part, when it is used for a liquid crystal display. <P>SOLUTION: The color filter is provided with a transparent substrate, a colored layer formed on the transparent substrate; a transparent electrode layer formed on the colored layer and protrusions for liquid crystal alignment layer control formed in a region, corresponding to the colored layer on the transparent electrode layer; the protrusions for liquid crystal alignment layer control contains at least one organic pigment selected from among a group consisting of a red organic pigment, a blue organic pigment and a purple organic pigment. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a color filter used in a vertical alignment liquid crystal display device.

  In a liquid crystal display device, a transparent substrate on the color filter side and a liquid crystal driving side substrate are opposed to each other, and a liquid crystal compound is sealed between the two to form a thin liquid crystal layer, and the liquid crystal driving side substrate forms a liquid crystal array in the liquid crystal layer. Display is performed by selectively changing the amount of transmitted or reflected light of the color filter under electrical control.

  In recent years, there has been proposed a vertical alignment liquid crystal display device in which liquid crystal molecules are arranged perpendicular to a substrate surface in a state where no voltage is applied, and the liquid crystal molecules are tilted in various directions when a voltage is applied. This vertical alignment liquid crystal display device is superior in terms of contrast ratio, response speed, and the like as compared with a twisted nematic liquid crystal display device conventionally used. In addition, when the direction in which the liquid crystal molecules are tilted is set to a large number of directions, there is an advantage that a high viewing angle can be effectively realized.

  As a vertical alignment liquid crystal display device in which the liquid crystal is tilted in many directions, for example, as shown in FIG. 2, the surface of the transparent electrode layer 3 and the electrode layer formed on the opposite liquid crystal driving side substrate 12 are used. 11 has been proposed in which a liquid crystal alignment control protrusion 4 is formed on the surface 11 and the alignment direction of the liquid crystal 13 when a voltage is applied (hereinafter also referred to as MVA method) (for example, Patent Document 1). ).

  In the vertically aligned liquid crystal display device, black display is performed in a state where the liquid crystal is vertically aligned, that is, in a state where no voltage is applied. However, since the liquid crystal alignment control protrusion is formed in the MVA method, the liquid crystal around the liquid crystal alignment control protrusion is not perfectly vertically aligned when no voltage is applied. For this reason, there is a problem that the backlight light leaks during black display, and the contrast between the black display portion and the white display portion is small.

  Therefore, a method of improving the contrast between the black display portion and the white display portion by adding a light shielding material or the like to the liquid crystal alignment control protrusion has been proposed. When a pigment dispersion using a dispersant is added, there is a problem in that the reliability of the liquid crystal alignment control protrusions is lowered and liquid crystal alignment failure occurs. Also, depending on the type of resin used for forming the liquid crystal alignment control protrusion, there is a problem that display failure occurs due to flickering. This is because current flows due to the influence of ionic impurities present in the liquid crystal alignment control protrusions, so that the voltage holding ratio is lowered, so that the liquid crystal alignment is not accurately controlled, and the light transmittance varies. It is because it ends up.

JP 2003-75839 A

  Therefore, it is desired to provide a color filter that is less likely to cause display defects such as alignment failure and flicker when used in a liquid crystal display device and has high contrast between the white display portion and the black display portion.

  The present invention is formed in a region corresponding to the transparent substrate, the colored layer formed on the transparent substrate, the transparent electrode layer formed on the colored layer, and the colored layer on the transparent electrode layer. A color filter having a liquid crystal alignment control protrusion, wherein the liquid crystal alignment control protrusion contains at least one organic pigment selected from the group consisting of a red organic pigment, a blue organic pigment, and a purple organic pigment. A color filter is provided.

According to the present invention, the one or more organic pigments selected from the group consisting of a red organic pigment, a blue organic pigment, and a purple organic pigment are contained, so that the formed liquid crystal alignment control protrusions are human. Due to the visual characteristics, the green color that is bright can be prevented from being transmitted. Therefore, when such a liquid crystal alignment control projection is used in a liquid crystal display device, even if backlight leakage occurs during black display, the apparent luminance can be lowered and display characteristics are good. Can be.
Further, according to the present invention, at least one organic pigment selected from the group consisting of a red organic pigment, a blue organic pigment, and a purple organic pigment is contained, so that the exposure light is less absorbed and the exposure light is transmitted. The liquid crystal alignment control protrusion forming composition can be easily formed, and the liquid crystal alignment control protrusion can be formed with good plate-making property.
In addition, according to the present invention, since the organic pigment is contained, the organic pigment usually has low conductivity. Therefore, when the protrusion for controlling the alignment of liquid crystal is used, there is no possibility that the alignment failure of the liquid crystal occurs. Can do.

  Moreover, in this invention, it is preferable that the dispersing agent used in order to disperse | distribute the said organic pigment has a structure represented by following General formula (1). This is because it is possible to form a pigment dispersion with good plate making properties and high reliability.

(式（１）中、Ｒ^１は、（ＣＨ_２）_４または（ＣＨ_２）_５を示し、Ｒ^２は炭素数５〜１５のアルキル基を示し、Ｒ^１は、一化合物中、それぞれ一種であってもよく二種以上であっても良い。ｎ、ｍはそれぞれ独立し、ｎは０〜１０、ｍは０〜２０の整数である。)

(In Formula (1), R ¹ represents (CH ₂ ) ₄ or (CH ₂ ) ₅ , R ² represents an alkyl group having 5 to 15 carbon atoms, and R ¹ represents one type in each compound. There may be two or more types, n and m are each independent, n is 0 to 10, and m is an integer of 0 to 20.)

  In the above invention, it is preferable that the liquid crystal alignment control protrusion is formed using a liquid crystal alignment control protrusion forming composition containing at least a negative resin composition. This is because the liquid crystal alignment control protrusions can be efficiently formed at a uniform height.

  ADVANTAGE OF THE INVENTION According to this invention, when it uses for a liquid crystal display device, display defects, such as alignment failure and flickering, do not occur easily, and it can be set as a high quality color filter with a large contrast of a white display part and a black display part.

Hereinafter, the color filter of the present invention will be described.
The color filter of the present invention includes a transparent substrate, a colored layer formed on the transparent substrate, a transparent electrode layer formed on the colored layer, and a region corresponding to the colored layer on the transparent electrode layer. A liquid crystal alignment control protrusion formed, wherein the liquid crystal alignment control protrusion is at least one organic pigment selected from the group consisting of a red organic pigment, a blue organic pigment, and a purple organic pigment. It is characterized by containing.

  The color filter of the present invention includes, for example, as shown in FIG. 1, a transparent substrate 1, a colored layer 2 formed on the transparent substrate 1, a transparent electrode layer 3 formed on the colored layer 2, and the above It has a liquid crystal alignment control protrusion 4 formed in a region corresponding to each colored layer 2 on the transparent electrode layer 3. A black matrix layer 5 may be formed between the adjacent colored layers 2. Note that the liquid crystal alignment control protrusions 4 are formed in the regions corresponding to the colored layers 2 on the transparent electrode layer 3, indicating that the colored layers 2 and the liquid crystal alignment controls are sandwiched between the transparent electrode layers 3. It means that the projection 4 is formed so as to correspond.

  According to the present invention, by containing at least one organic pigment selected from the group consisting of a red organic pigment, a blue organic pigment, and a purple organic pigment, a liquid crystal alignment that does not transmit green that feels bright on human visual characteristics Control protrusions can be formed. This is because the red organic pigment, the blue organic pigment, and the purple organic pigment absorb the green wavelength. Therefore, when the liquid crystal alignment control protrusion is used in a liquid crystal display device, even if backlight light leaks during black display, the apparent luminance can be lowered and good display characteristics can be obtained. .

1. First, the liquid crystal alignment control protrusion used in the present invention will be described.
The liquid crystal alignment control protrusion used in the present invention is formed on a transparent electrode layer to be described later, and controls the alignment of the liquid crystal. In addition, the liquid crystal alignment control protrusion used in the present invention is characterized by containing one or more organic pigments selected from the group consisting of a red organic pigment, a blue organic pigment, and a purple organic pigment.

  In the present invention, the above-described pigment is used for the liquid crystal alignment control protrusion, and a specific dispersant is preferably used. Each will be described below.

(1) Organic Pigment The organic pigment used in the composition for liquid crystal alignment protrusions used in the present invention is one or more organic compounds selected from the group consisting of red organic pigments, blue organic pigments, and purple organic pigments. Pigment. Hereinafter, each pigment will be described.

Specific examples of the red organic pigment include PR (Pigment Red) 109, 122, 123, 166, 177, 190, 206, 209, 215, 242 and 254. Among them, PR177 or PR254 is used. It is preferable.
Specific examples of the blue organic pigment include PB (Pigment Blue) 15: 1, 15: 2, 15: 3, 15: 4, 15: 5, and 15: 6. Among them, PB15: 6 Is preferably used.
Specific examples of the purple organic pigment include PV (Pigment Violet) 19 and 23. Among them, PV23 is preferably used.

  About the organic pigment mentioned above, at least 1 type should just contain, only 1 type may be used and 2 or more types may be mixed and used.

  The protrusion for controlling liquid crystal alignment of the present invention preferably contains the red organic pigment and the blue organic pigment. The liquid crystal alignment control protrusion of the present invention preferably contains the purple organic pigment. Thus, when the liquid crystal alignment control protrusion is used in a liquid crystal display device, it is possible to make green transmission less transmitted, and thus it is possible to further reduce the apparent luminance. Further, it is possible to form the liquid crystal alignment control protrusions with good platemaking properties.

(2) Dispersant The dispersant used in the present invention is used for dispersing the organic pigment.
The dispersant used in the present invention is not particularly limited as long as the organic pigment can be uniformly dispersed.
In the present invention, the dispersant used preferably has a structure represented by the following general formula (1). This is because it is possible to form a pigment dispersion with good plate making properties and high reliability.

(式（１）中、Ｒ^１は、（ＣＨ_２）_４または（ＣＨ_２）_５を示し、Ｒ^２は炭素数５〜１５のアルキル基を示し、Ｒ^１は、一化合物中、それぞれ一種であってもよく二種以上であっても良い。ｎ、ｍはそれぞれ独立し、ｎは０〜１０、ｍは０〜２０の整数である。)

(In Formula (1), R ¹ represents (CH ₂ ) ₄ or (CH ₂ ) ₅ , R ² represents an alkyl group having 5 to 15 carbon atoms, and R ¹ represents one type in each compound. There may be two or more types, n and m are each independent, n is 0 to 10, and m is an integer of 0 to 20.)

(3) Liquid crystal alignment control protrusion forming composition The liquid crystal alignment control protrusion used in the present invention is formed using the liquid crystal alignment control protrusion forming composition containing the organic pigment and the dispersant described above.
The liquid crystal alignment control protrusion forming composition contains at least the organic pigment, the dispersant and the resin composition described above. Hereinafter, the resin composition will be described.

(A) Resin Composition The resin composition used in the present invention is not particularly limited as long as the desired liquid crystal alignment control protrusion can be formed, and the negative resin composition. It may also be a positive resin composition. In the present invention, it is particularly preferable to use a negative resin composition. Since other members such as a colored layer and a columnar spacer of a general color filter are formed using a negative resin composition, the negative resin composition should be used as a projection forming composition for controlling liquid crystal alignment. This eliminates the need for a step of changing the developing solution when forming the liquid crystal alignment control protrusions, and allows the color filter to be efficiently manufactured.

  Further, by using a negative resin composition, there is an advantage that the plate-making property can be improved even when the amount of the light shielding material described later is large. Furthermore, when forming projections for controlling the alignment of liquid crystals, a composition for forming projections for controlling the alignment of liquid crystals in the region where the projections for controlling the alignment of liquid crystals are formed even when exposure light wraps around (diffraction) occurs Since it does not dissolve in the developer, the height of the liquid crystal alignment control protrusions formed does not vary, and the liquid crystal alignment control protrusions can be formed at a uniform height on the entire color filter. Become. Furthermore, it is advantageous in that the liquid crystal alignment control protrusions can be miniaturized and the liquid crystal alignment control protrusions can be formed at a uniform height on a large-area color filter.

(I) Negative type resin composition As a negative type resin composition, it can be set as the composition containing a polyfunctional acrylate monomer, a polymer, and a photoinitiator, for example.

(Multifunctional acrylate monomer)
As the polyfunctional acrylate monomer used in the negative resin composition, a compound having two or more ethylenically unsaturated bond-containing groups such as an acryl group or a methacryl group is used. ) Acrylate, diethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, hexane di (meth) acrylate, neo Pentyl glycol di (meth) acrylate, glycerin di (meth) acrylate, glycerin tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, 1,4-butanediol diacrylate DOO, pentaerythritol (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate can be exemplified dipentaerythritol penta (meth) acrylate.

  You may use a polyfunctional acrylate monomer in combination of 2 or more types. In the present invention, (meth) acryl means either acryl or methacryl, and (meth) acrylate means either an acrylate group or methacrylate.

(polymer)
Examples of the polymer used in the negative curable resin composition 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, cellulose acetate propionate, cellulose acetate butyrate, nylon 6, nylon 66, nylon 12, polyethylene terephthalate, poly Butylene 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, polyether imide resin, phenol resin, may be mentioned urea resin and the like.

  Furthermore, as the 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 and a dimer of (meth) acrylic acid and acrylic acid (for example, Toagosei Chemical Co., Ltd.) M-5600), itaconic acid, ku Tonsan, maleic acid, fumaric acid, vinyl acetate, polymers or copolymers comprising one or more selected from among these anhydrides can also be exemplified. Moreover, although the polymer etc. which added the ethylenically unsaturated compound which has a glycidyl group or a hydroxyl group to said copolymer can be illustrated, it is not limited to these.

(Photopolymerization initiator)
As the photopolymerization initiator used in the present invention, general ones can be used. For example, radical photopolymerization initiators such as Michler's ketone, and cationic photopolymerizations such as triarylsulfonium salts and diaryliodonium salts. An initiator etc. can be mentioned. These may be used alone or in combination of two or more.

  Moreover, such a photoinitiator can be used in combination with a photosensitizer. As the photosensitizer, a general one can be used, and examples thereof include N, N-dimethylaminobenzoic acid ethyl ester, N, N-dimethylaminobenzoic acid isoamyl ester, triethanolamine, and triethylamine. . These photosensitizers may be used alone or in combination of two or more.

  The photopolymerization initiator is preferably contained in the solid content of the liquid crystal alignment control protrusion-forming composition in the range of 1% by weight to 30% by weight, especially in the range of 5% by weight to 20% by weight. . This is because the curability of the liquid crystal alignment control protrusion forming composition can be made sufficient.

(Ii) Positive Resin Composition In the present invention, a positive resin composition can also be used.
Specifically, the positive resin composition may be a mixture of a positive resin used for forming a general color filter and various additives. Examples of the positive type resin include quinonediazides such as naphthoquinonediazide and benzoquinonediazide, diazo compounds such as diazomethyldrum acid, diazodimedone and 3-diazo-2,4-dione, o-nitrobenzyl ester, and onium salt. , Photodecomposer (dissolution inhibitor) such as a mixture of onium salt, polyphthalaldehyde and t-butyl choline, hydroquinone, phloroglucin, 2,3,4-trihydroxybenzophenone having OH group and soluble in alkali Such as monomers, novolak resins such as phenol novolac resin and cresol novolak resin, copolymers of styrene and maleic acid and maleimide, and mixtures and condensates of polymers such as phenolic and methacrylic acid, styrene and acrylonitrile copolymers, Or polymethyl Tacrylate, polymethyl methacrylate, polyhexafluorobutyl methacrylate, polydimethyltetrafluoropropyl methacrylate, trichloroethyl methacrylate, methyl methacrylate-acrylonitrile copolymer, polymethyl isopropenyl ketone, poly α-cyanoacrylate, And polytrifluoroethyl-α-chloroacrylate. Among these, from the viewpoint of versatility, a mixed / condensed product containing a novolak resin as a main component is preferably used.

(B) Other components In the liquid crystal alignment control projection composition, a surfactant, an adhesion assistant, a solvent, and the like are usually used in accordance with the material. Each will be described below.

(I) Surfactant In the present invention, a surfactant may be contained as necessary. The surfactant is used for improving the coating property of the composition for forming a protrusion for controlling liquid crystal alignment in the present invention or for improving the developability of the coating film.

  Examples of the surfactant used in the present invention include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether; polyoxyethylene octylphenyl ether, polyoxyethylene nonylphenyl Polyoxyethylene aryl ethers such as ethers; nonionic surfactants such as polyoxyethylene dialkyl esters (for example, polyoxyethylene dilaurate and polyoxyethylene distearate); Ftop EF301, Ftop 303, Ftop 352 (Manufactured by Shin-Akita Kasei Co., Ltd.); Megafuck F171, Megafuck F172, Megafuck F173 (manufactured by Dainippon Ink & Chemicals, Inc.); Florard FC-430, Lollard FC-431 (manufactured by Sumitomo 3M); Asahi Guard AG710, Surflon S-382, Surflon SC-101, Surflon SC-102, Surflon SC-103, Surflon SC-104, Surflon SC-105, Surflon SC- 106 (manufactured by Asahi Glass Co., Ltd.) and other commercially available fluorine-based surfactants; organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.); (meth) acrylic acid copolymer polyflow no. 57, 95 (manufactured by Kyoeisha Yushi Chemical Co., Ltd.); These may be used alone or in combination of two or more.

  The content of the surfactant is preferably 1% by weight or less, and more preferably 0.5% by weight or less, based on the solid content in the liquid crystal alignment control protrusion-forming composition.

(Ii) Adhesion aid In the present invention, an adhesion aid may be contained as necessary. The adhesion assistant is used to improve the adhesion between the coating film and the transparent electrode layer, etc., when the liquid crystal alignment control protrusion forming composition of the present invention is applied on the transparent electrode layer. Examples of such adhesion assistants include silane coupling agents.

  The content of the adhesion assistant is preferably 10% by weight or less, more preferably 5% by weight or less, based on the solid content in the liquid crystal alignment control protrusion-forming composition.

(Iii) Solvent In the present invention, a solvent may be contained as necessary. The solvent is used to uniformly dissolve each component in the liquid crystal alignment control protrusion-forming composition and facilitate application on the transparent electrode layer.

  The solvent used in the present invention is not particularly limited as long as it is an organic solvent that does not react with each component in the liquid crystal alignment control protrusion-forming composition and can dissolve or disperse them. Specifically, alcohols such as methanol and ethanol; ethers such as tetrahydrofuran; glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol dimethyl ether, ethylene glycol methyl ethyl ether, and ethylene glycol monoethyl ether; methyl cellosolve acetate, ethyl Ethylene glycol alkyl ether acetates such as cellosolve acetate; diethylene glycols such as diethylene glycol monomethyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether; propylene glycol methyl ether Propylene glycol alkyl ether acetates such as cetate and propylene glycol ethyl ether acetate; aromatic hydrocarbons such as toluene and xylene; ketones such as methyl ethyl ketone, methyl amyl ketone, cyclohexanone and 4-hydroxy-4-methyl-2-pentanone And ethyl 2-hydroxypropionate, methyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-2-methylbutanoate, Estes such as methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, ethyl acetate, butyl acetate, methyl lactate, ethyl lactate Kind; and the like. These solvents may be used alone or in combination of two or more.

  Of these, glycol ethers, alkylene glycol alkyl ether acetates, diethylene glycol dialkyl ethers, and diethylene glycols are preferable as the solvent. Particularly preferred are ethyl 3-ethoxypropionate, ethyl lactate, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, methyl amyl ketone, and diethylene glycol ethyl methyl ether.

  In the composition for forming protrusions for controlling liquid crystal alignment in the present invention, the component excluding the solvent is preferably 5% by weight to 40% by weight, more preferably 10% by weight to 30% by weight. Add solvent. Thereby, it can be set as the viscosity suitable for application | coating.

(Iv) Additive In the present invention, an additive may be contained as necessary. Examples of the additive include an antistatic agent, a storage stabilizer, an antifoaming agent, a polymerization inhibitor, a plasticizer, and a leveling agent.

  Examples of the plasticizer include dibutyl phthalate, dioctyl phthalate, and tricresyl. Examples of the antifoaming agent and leveling agent include silicon-based, fluorine-based, and acrylic compounds.

(4) Method for forming liquid crystal alignment control protrusions The liquid crystal alignment control protrusions used in the present invention can be formed in the same manner as that used when forming a general color filter. The description in is omitted.

2. Next, the colored layer used in the present invention will be described. The colored layer used in the present invention usually includes three colors of red, green, and blue, but in the present invention, for example, four or more colors may be included.

  Further, the shape and arrangement of the colored layer used in the present invention are not particularly limited, and may be a known arrangement such as a stripe type, a mosaic type, a triangle type, a four-pixel arrangement type, and the colored area is It can be set arbitrarily.

  Moreover, the formation method of the colored layer used for this invention is not specifically limited, The pigment dispersion method etc. which are used in the case of manufacture of the colored layer of a general color filter can be used. In addition, the material of the colored layer used in the present invention can be the same as that of the colored layer used in a general color filter, and thus detailed description thereof is omitted here.

3. Transparent electrode layer Next, the transparent electrode layer used for the color filter of this invention is demonstrated. The transparent electrode layer used in the color filter of the present invention can be the same as the transparent electrode layer used in a general color filter. For example, indium tin oxide (ITO), zinc oxide (ZnO), tin oxide ( It can be formed by a general film forming method such as a sputtering method, a vacuum vapor deposition method, a CVD method, etc. using SnO) and the like and alloys thereof. The thickness of such a transparent electrode layer can usually be about 0.01 μm to 1 μm.

4). Transparent substrate Next, the transparent substrate used in the present invention will be described. The transparent substrate used in the present invention is not particularly limited as long as the colored layer can be formed. Examples of such transparent substrates include non-flexible transparent rigid materials such as alkali-free glass, quartz glass, Pyrex (registered trademark) glass, and synthetic quartz plates, or transparent resin films and optical resin plates. A transparent flexible material having flexibility can be used.

5. Color filter The color filter of the present invention corresponds to a transparent substrate, a colored layer formed on the transparent substrate, a transparent electrode layer formed on the colored layer, and the colored layer on the transparent electrode layer. And a liquid crystal alignment control protrusion formed in the region.

  The color filter of the present invention is not particularly limited as long as it has the transparent substrate, the colored layer, the transparent electrode layer, and the liquid crystal alignment control protrusion, and is appropriately selected according to the type of the liquid crystal display device used. Its configuration is selected. For example, a material in which a black matrix layer is formed between the colored layer and the colored layer may be used. Further, when the color filter of the present invention is used for a transflective liquid crystal display device, it is between the colored layer and the transparent substrate in the region to be the reflected light region, or between the colored layer and the transparent electrode layer, etc. A transparent resin layer or the like for adjusting the cell gap or the like may be provided. Such a black matrix layer, a transparent resin layer, and the like can be the same as those used for a general color filter or a color filter for a transflective liquid crystal display device.

  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.

  As examples and comparative examples, organic pigments are used as materials contained in the liquid crystal alignment control protrusions, and liquid crystal alignment control protrusions containing these in various contents are formed, and C / R measurement is performed. It was.

[Example 1]
(Formation of black matrix layer)
First, the following components were mixed and sufficiently dispersed in a sand mill to prepare a black pigment dispersion.
<Black pigment dispersion>
・ Black pigment 23 parts by weight ・ Polymer dispersant (Big Chemie Japan Co., Ltd. Disperbyk 111) 2 parts by weight ・ Solvent (diethylene glycol dimethyl ether) 75 parts by weight

Next, the following components were sufficiently mixed to obtain a light shielding layer composition.
<Composition for light shielding layer>
-61 parts by weight of the above black pigment dispersion-20 parts by weight of curable resin composition-30 parts by weight of diethylene glycol dimethyl ether

  And the said composition for light shielding layers was apply | coated with the spin coater on the glass substrate (Asahi Glass Co., Ltd. AN material) of thickness 1.1mm, and it dried for 3 minutes at 100 degreeC, and formed the light shielding layer with a film thickness of about 1 micrometer. . The light-shielding layer is exposed to a light-shielding pattern with an ultrahigh pressure mercury lamp, developed with a 0.05 wt% aqueous potassium hydroxide solution, and then subjected to heat treatment by leaving the substrate in an atmosphere of 180 ° C. for 30 minutes. A black matrix layer was formed in a region where the black matrix layer was to be formed.

(Formation of colored layer)
A red curable resin composition having the following composition is applied to the substrate on which the black matrix layer is formed as described above by a spin coating method (application thickness: 1.5 μm), and then dried in an oven at 70 ° C. for 3 minutes. did. Next, a photomask is disposed at a distance of 100 μm from the coating film of the red curable resin composition, and ultraviolet rays are applied only to the region corresponding to the colored layer forming region using a 2.0 kW ultrahigh pressure mercury lamp by a proximity aligner. Irradiated for 10 seconds. Subsequently, it was immersed in 0.05 wt% potassium hydroxide aqueous solution (liquid temperature 23 degreeC) for 1 minute, and alkali development was carried out, and only the uncured part of the coating film of a red curable resin composition was removed. Thereafter, the substrate was left in an atmosphere of 180 ° C. for 30 minutes to perform heat treatment, thereby forming a red relief pattern in a region where a red pixel was to be formed.
Next, using the green curable resin composition having the following composition, a green relief pattern was formed in a region where a green pixel was to be formed, in the same process as the red relief pattern formation.
Further, using a blue curable resin composition having the following composition, a blue relief pattern is formed in a region where a blue pixel is to be formed in the same process as that for forming a red relief pattern, and red (R), green (G ) And blue (B) were formed.

<Composition of red curable resin composition>
CI pigment red 177 10 parts by weight Polysulfonic acid type polymer dispersant 3 parts by weight Curable resin composition 5 parts by weight 3-methoxybutyl acetate 82 parts by weight <Composition of green curable resin composition >
CI Pigment Green 36 10 parts by weight Polysulfonic acid type polymer dispersant 3 parts by weight Curable resin composition 5 parts by weight 3-methoxybutyl acetate 82 parts by weight <Composition of blue curable resin composition >
CI Pigment Blue 15: 6 10 parts by weight Polysulfonic acid type polymer dispersant 3 parts by weight Curable resin composition 5 parts by weight 3-methoxybutyl acetate 82 parts by weight

(Formation of transparent electrode layer)
A transparent electrode layer was formed on the substrate on which the colored layer was formed, using a discharge temperature of argon and oxygen at a substrate temperature of 200 ° C., and using ITO as a target by a DC magnetron sputtering method.

(Formation of liquid crystal alignment control protrusions)
On the substrate on which the transparent electrode was formed, a dispersion prepared by the following method was added to a positive photosensitive resist containing a novolak resin so that the pigment concentration was 10%. The obtained positive photosensitive resist was patterned by the same method as the formation of the colored relief pattern to form liquid crystal alignment control protrusions.
<Preparation of dispersion>
Add PB15: 6 to PGMEA at a ratio of 40%, PR177 at 40%, PV23 at a ratio of 20%, and after dilution with a solvent so that the solid content concentration of the entire pigment is 15%, use a paint shaker. Dispersion treatment was performed to obtain a colored dispersion.

(Spacer formation)
On the board | substrate which formed the colored layer and the protective layer as mentioned above, the curable resin composition was apply | coated and dried by the spin coating method, and the coating film was formed. A photomask was placed at a distance of 100 μm from the coating film of the curable resin composition, and only a spacer formation region was irradiated with ultraviolet rays for 10 seconds using a 2.0 kW ultrahigh pressure mercury lamp by a proximity aligner. Subsequently, it was immersed in 0.05 wt% potassium hydroxide aqueous solution (liquid temperature 23 degreeC) for 1 minute, and alkali development was carried out, and only the uncured part of the coating film of the curable resin composition was removed. Thereafter, the substrate was left to stand in an atmosphere of 200 ° C. for 30 minutes to perform heat treatment to form a photo spacer having a height of 3.5 μm, thereby obtaining a color filter.

(Creation of liquid crystal display device)
An alignment film made of polyimide was formed on the film forming surface of the color filter obtained as described above. Next, a required amount of liquid crystal is dropped on the glass substrate on which the alignment film is formed, the color filters are overlaid, and a UV curable resin is used as a sealing material, and a pressure of 0.3 kgf / cm ² is applied at room temperature to 400 mJ / cm 2. The liquid crystal cell of the present invention was obtained by bonding by exposing at an exposure dose of ² and assembling the cells.

(Contrast evaluation)
When using Toshiba Mellow 5D FL10EX-DH as the light source, the liquid crystal cell produced between the two polarizing plates is placed horizontally on the two polarizing plates, and the polarizing plates are arranged so that they are crossed Nicols. The luminance when arranged in parallel was measured using a luminance meter (Minolta luminance meter LS-100). Contrast was obtained from the obtained luminance according to the following formula.
C / R = Paranicol luminance / Cross Nicol luminance

[Example 2]
A liquid crystal cell was produced in the same manner as in Example 1, except that the ratio of the pigment added to the dispersion used for forming the liquid crystal alignment control protrusions was changed as follows. Contrast evaluation was performed according to the method of Example 1 using the obtained liquid crystal cell.
<Pigment ratio>
・ PB15: 6 30%
・ PR254 70%

[Example 3]
A liquid crystal cell was produced in the same manner as in Example 1 except that the ratio of the pigment added to the dispersion used for forming the liquid crystal alignment control protrusions was changed as follows. Contrast evaluation was performed according to the method of Example 1 using the obtained liquid crystal cell.
<Pigment ratio>
・ PR254 20%
・ PV23 80%

[Example 4]
A liquid crystal cell was produced in the same manner as in Example 1 except that the ratio of the pigment added to the dispersion used for forming the liquid crystal alignment control protrusions was changed as follows. Contrast evaluation was performed according to the method of Example 1 using the obtained liquid crystal cell.
<Pigment ratio>
・ PB15: 6 40%
・ PV23 60%

[Example 5]
A liquid crystal cell was produced in the same manner as in Example 1 except that the ratio of the pigment added to the dispersion used for forming the liquid crystal alignment control protrusions was changed as follows. Contrast evaluation was performed according to the method of Example 1 using the obtained liquid crystal cell.
<Pigment ratio>
・ PB15: 6 35%
・ PR254 35%
・ PG36 30%

[Example 6]
A liquid crystal cell was produced in the same manner as in Example 1, except that the ratio of the pigment added to the dispersion used for forming the liquid crystal alignment control protrusions was changed as follows. Contrast evaluation was performed according to the method of Example 1 using the obtained liquid crystal cell.
<Pigment ratio>
・ PG36 10%
・ PR254 90%

[Comparative Example 1]
A liquid crystal cell obtained in the same manner as in Example 1 was used except that the spacer height was 3.75 μm and the ratio of the pigment added to the dispersion used for forming the liquid crystal alignment control was changed as follows. Contrast evaluation was performed.
<Pigment ratio>
・ PG36 40%
・ PY150 60%

[Comparative Example 2]
A liquid crystal cell was produced in the same manner as in Example 1 except that the pigment was not added to the dispersion used for forming the protrusions for controlling liquid crystal alignment. Contrast evaluation was performed according to the method of Example 1 using the obtained liquid crystal cell.

  Table 1 shows the results of contrast evaluation for each of Examples 1 to 6 and Comparative Examples 1 to 2.

[Evaluation]
In the example using the liquid crystal alignment control protrusions containing an organic pigment of any one of a red pigment, a blue pigment, and a violet pigment, high contrast was obtained.

It is a schematic sectional drawing for demonstrating the color filter of this invention. It is a schematic sectional drawing for demonstrating a general liquid crystal display device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Transparent substrate 2 ... Colored layer 3 ... Transparent electrode layer 4 ... Liquid crystal alignment control protrusion 5 ... Black matrix layer

Claims (3)

Liquid crystal alignment control formed in a transparent substrate, a colored layer formed on the transparent substrate, a transparent electrode layer formed on the colored layer, and a region corresponding to the colored layer on the transparent electrode layer A color filter having protrusions,
The color filter, wherein the liquid crystal alignment control protrusion contains at least one organic pigment selected from the group consisting of a red organic pigment, a blue organic pigment, and a purple organic pigment. The color filter according to claim 1, wherein the dispersant used for dispersing the organic pigment has a structure represented by the following general formula (1).

(In Formula (1), R ¹ represents (CH ₂ ) ₄ or (CH ₂ ) ₅ , R ² represents an alkyl group having 5 to 15 carbon atoms, and R ¹ represents one type of each compound. There may be two or more types, n and m are each independent, n is 0 to 10, and m is an integer of 0 to 20.)   The color filter according to claim 1, wherein the liquid crystal alignment control protrusion is formed using a liquid crystal alignment control protrusion forming composition containing a negative resin composition.

Images