JP2007148072A - Near ir absorption filter, front filter for plasma display, and their manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a near IR absorption filter which reduces the deterioration in heat and light and is excellent in productivity and environmental aptitude, a near IR absorption filter manufactured by the method, and a front filter for plasma display. <P>SOLUTION: The method for manufacturing the near IR absorption filter formed by coating the surface of a transparent support with a near IR absorption layer is characterized in that the near IR absorption layer is formed by coating the surface of the support with a coating liquid containing near IR absorption dye dispersed in a high boiling point solvent and drying the coating by heating. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for producing a near-infrared absorption filter having high productivity, excellent storage stability and weather resistance, and a near-infrared absorption filter produced by the method and a front filter for a plasma display.

  In a plasma display panel (PDP), a rare gas is put into a plasma state to emit ultraviolet rays, and this light beam causes phosphors to emit light. At this time, near infrared rays of 800 to 1000 nm are also emitted. This near-infrared radiation is harmful to peripheral devices, and there are differences between peripheral devices, but near-infrared rays emitted from plasma displays and remote controls for televisions and coolers for home appliances, other special remote controls for business use, etc. Are wavelengths in the same region. Therefore, near infrared rays in the above wavelength region emitted by the plasma display cause malfunction of peripheral devices where the plasma display is installed. Therefore, it is necessary to prevent malfunctions of operation elements such as a remote controller. There is an increasing demand for emission shielding.

  In response to this requirement, the method of attaching a near-infrared absorption filter to the front glass of the PDP is simple and advantageous in terms of cost, and this method has become mainstream.

  However, due to the heat generation and ultraviolet rays of PDP, degradation of near-infrared absorbing filters is an issue, and the development of heat-resistant infrared absorbing dyes and the combined use of ultraviolet absorbers with good absorption efficiency are satisfactory, but satisfactory performance Therefore, improvement is desired.

  In addition, the deterioration of the near-infrared absorbing dye is greatly affected by moisture, so that there is a method of applying it in a non-aqueous system so that it is not affected by water (for example, see Patent Document 1), but it is affected by the residual organic solvent. There is a method (for example, refer to Patent Document 2) in which a dye is present during polymerization of a solventless hydrophobic resin and a monomer and a polymerization initiator are molded and used. Therefore, productivity is inferior.

  In addition, a method (for example, see Patent Document 3) in which a dye is solid-dispersed in an aqueous solvent has been proposed. However, this method is not only slightly affected by moisture but has poor storage stability.

  In addition, gelatin-dispersed water-based coating (for example, see Patent Document 4), which is advantageous for high productivity by high-speed thin film coating, has a deterioration in high-temperature and high-humidity storage of near-infrared absorbing dyes because of the water retention property of gelatin. The current situation is inevitable.

Under such circumstances, there has been a demand for a near-infrared absorbing filter that is less deteriorated by light and heat and that is excellent in environmental suitability.
JP 10-186127 A (paragraph number 0059) JP 11-109126 A (paragraph numbers 0042-0043) JP-A-11-109560 (paragraph number 0105) JP-A-10-333295 (paragraph numbers 0071 to 0131)

  Therefore, the present invention has been made in view of the above-mentioned problems, and its purpose is to produce a near-infrared absorption filter that has little deterioration against heat and light, and that is excellent in productivity and environmental suitability, and the method thereof. It is to provide a near-infrared absorption filter and a front filter for a plasma display to be manufactured.

  The above object of the present invention can be achieved by the following configuration.

  1. In a method for producing a near-infrared absorbing filter comprising a near-infrared absorbing layer coated on a transparent support, a coating solution containing a near-infrared absorbing dye in which the near-infrared absorbing layer is dispersed in a high-boiling solvent is applied on the support. A method for producing a near-infrared absorbing filter, which is formed by applying to a substrate and drying by heating.

  2. 30. The method for producing a near-infrared absorbing filter according to 1, wherein 30% by mass or more and 99% by mass or less of the solvent of the coating solution for the near-infrared absorbing layer is water.

  3. 3. The method for producing a near-infrared absorbing filter according to 1 or 2, wherein the content of the high boiling point solvent is 1 to 30% by mass of the total amount of the binder in the near-infrared absorbing layer.

  4). The above-mentioned 1-3, wherein the near-infrared absorbing layer contains at least one compound selected from a diimonium compound, a nickel dithiol compound, a phthalocyanine compound, a squarylium compound, and a croconium compound as the near-infrared absorbing dye. The manufacturing method of the near-infrared absorption filter as described in any one of Claims.

  5. The near-infrared absorption filter manufactured by the manufacturing method as described in any one of said 1-4.

  6). 6. A front filter for plasma display, comprising the near-infrared absorption filter as described in 5 above.

  According to the configuration of the present invention, there is provided a near-infrared absorption filter manufacturing method that is less susceptible to heat and light, has excellent productivity and environmental suitability, a near-infrared absorption filter manufactured by the method, and a front filter for plasma display can do.

  Hereinafter, the present invention and components will be described in detail.

(Dispersion in high boiling point solvent)
In the present invention, at least one layer on the support contains a high-boiling-point solvent dispersion having an average dispersed particle size of dispersion (near infrared absorbing dye) particles of 0.12 μm or less. Here, the high boiling point solvent dispersion is a high boiling point solvent dispersion containing an organic compound that is water-insoluble (at 25 ° C., the solubility is 3 g or less, preferably 1 g or less with respect to 100 g of distilled water). Examples of the water-insoluble organic compound include an ultraviolet absorber, a color turbidity inhibitor, and an antifading agent.

  The high boiling point solvent dispersion of the dispersion according to the present invention is contained in the near infrared absorption layer. The average particle size of the dispersion (near infrared absorbing dye) particles in the high-boiling solvent dispersion is 0.12 μm or less, preferably 0.02 to 0.11 μm, more preferably 0.04 to 0.10 μm. The average dispersed particle size is adjusted by optimizing the type and amount of surfactant, adjusting the viscosity of the high boiling point solvent dispersion, increasing the emulsification time of the dispersion emulsifier, and adjusting the pressure and shear force. Is done. The average dispersed particle size can be measured with a nanosizer manufactured by Coulter, England.

  The high-boiling solvent dispersion of the near-infrared absorbing dye according to the present invention is prepared by dissolving the dye in a water-insoluble high-boiling organic solvent (for example, tricresyl phosphate, dibutyl phthalate, dinonylphenol, etc.) What can be obtained as a fine high-boiling organic solvent (oil) dispersion by the above method is preferred. The boiling point of the water-insoluble high-boiling organic solvent is preferably 100 ° C. or higher, particularly preferably a solvent having a temperature of 140 ° C. or higher and 300 ° C. or lower. The dispersion medium during dispersion is not particularly limited, and examples thereof include polyacrylic acid and acrylic acid. Copolymers, maleic acid copolymers, maleic acid monoester copolymers, acryloylmethylpropanesulfone copolymers, and other synthetic anionic polymers, carboxymethyl starch, semi-synthetic polymers such as carboxymethylcellulose, alginic acid, pectic acid, etc. Anionic polymers, anionic surfactants described in JP-A-52-92716, WO88 / 04794, etc., compounds described in Japanese Patent Application No. 7-350753, or known anionic, nonionic, cationic Surfactants, other polyvinyl alcohol, polyvinylpipes Pyrrolidone, carboxymethyl cellulose, hydroxypropyl cellulose, known polymers such as hydroxypropyl methylcellulose, or a polymer compound existing in nature, such as gelatin can be suitably selected and used.

  The content of the high boiling point solvent is preferably 1 to 30% by mass, more preferably 3 to 25% by mass, and most preferably 5 to 20% by mass, based on the total amount of the binder in the near infrared absorption layer. When the content is less than the above range, the near-infrared absorbing dye is not sufficiently dispersed in the high boiling point solvent, so that the desired absorbance cannot be obtained, and when the content is more than the above range. Because the dispersed high-boiling solvent aggregates in the coating film over time, and the absorbance decreases, or the sweating phenomenon that the high-boiling solvent appears as oil droplets on the coating surface occurs. It is not preferable.

(Near-infrared absorbing dye)
Specific examples of near infrared absorbing dyes that can be used in the present invention include polymethine, phthalocyanine, naphthalocyanine, metal complex, aminium, imonium, diimonium, anthraquinone, dithiol metal complex, naphthoquinone, Examples include indolephenol-based, azo-based, and triallylmethane-based compounds. The PDP optical filter is required to have near-infrared absorptivity mainly for absorption of heat rays and noise prevention of electronic devices. For this purpose, a dye having a near-infrared absorbing ability having a maximum absorption wavelength of 750 to 1100 nm is preferable, and a metal complex, aminium, phthalocyanine, naphthalocyanine, diimonium, and squalium compound are preferable.

  In particular, in the present invention, the near infrared absorbing dye preferably contains at least one compound selected from diimonium compounds, nickel dithiol compounds, phthalocyanine compounds, squarylium compounds, and croconium compounds.

  The absorption maximum of conventionally known nickel dithiol complex-based compounds or fluorinated phthalocyanine-based compounds is 700 to 900 nm, and in practical use, usually an aminium-based compound having an absorption maximum in a longer wavelength region than the above compounds. In particular, when used in combination with a diimmonium compound, an effective near infrared absorption effect can be obtained.

  Diimonium compounds The following can be represented by the general formula (1).

In the general formula (1), R _{1 to} R ₈ each independently represent a hydrogen atom, an alkyl group, a substituted alkyl group, a cyclic alkyl group, an alkenyl group, an aralkyl group, or a substituted aralkyl group, Either a chain or a branched chain may be used. Also, they may be the same or different. X represents an anion.

In R _{1 to} R ₈ , examples of the alkyl group, substituted alkyl group, cyclic alkyl group, alkenyl group, aralkyl group or substituted aralkyl group include the following.

  Examples of the alkyl group include a methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, sec-butyl group, t-butyl group, n-pentyl group, iso- As a substituted alkyl group, a pentyl group, a t-pentyl group, an n-hexyl group, an n-octyl group (preferably having 1 to 10 carbon atoms), for example, a 2-hydroxyethyl group, a 3-hydroxypropyl group 4-hydroxybutyl group, 2-acetoxyethyl group, carboxymethyl group, 2-carboxyethyl group, 3-carboxypropyl group, 2-sulfoethyl group, 3-sulfopropyl group, 4-sulfobutyl group, 3-sulfatepropyl Group, 4-sulfate butyl group, N- (methylsulfonyl) -carbamylmethyl group, 3- (acetylsulfamyl) propyl 4- (acetylsulfamyl) butyl group, cyanomethyl group, 2-cyanoethyl group, 3-cyanopropyl group, 2-cyanopropyl group, 4-cyanobutyl group, 3-cyanobutyl group, 2-cyanobutyl group, 5-cyano Pentyl group, 4-cyanopentyl group, 3-cyanopentyl group, 2-cyanopentyl group, 6-cyanohexyl group, 5-cyanohexyl group, 4-cyanohexyl group, 3-cyanohexyl group, 2-cyanohexyl group Etc., as a cyclic alkyl group, for example, cyclohexyl group, etc., as alkenyl group, for example, vinyl group, allyl group, propenyl group, etc., as aralkyl group, for example, benzyl group, phenethyl group, α-naphthyl, etc. Examples of the methyl group, β-naphthylmethyl group, and substituted aralkyl group include carboxybenzyl group, sulfobe Jill group, hydroxybenzyl group, and the like, respectively. In R, an alkyl group having 3 to 6 carbon atoms or an alkyl group substituted with a cyano group is more preferably used.

  X is a monovalent anion or a divalent anion.

  Examples of monovalent anions include organic acid monovalent anions and inorganic monovalent anions. Examples of organic acid monovalent anions include acetate ions, lactate ions, trifluoroacetate ions, propionate ions, benzoate ions, oxalate ions, succinate ions, stearic acid ions, and other organic carboxylate ions, methanesulfonate ions, Organic sulfonate ions such as toluene sulfonate ion, naphthalene monosulfonate ion, chlorobenzene sulfonate ion, nitrobenzene sulfonate ion, dodecylbenzene sulfonate ion, benzene sulfonate ion, ethane sulfonate ion, trifluoromethane sulfonate ion, tetra And organic borate ions such as phenylborate ion and butyltriphenylborate ion, and preferably halogenoalkyl sulfate such as trifluoromethanesulfonate ion and toluenesulfonate ion. Phosphate ion or alkyl arylsulfonate ion.

  Examples of the inorganic monovalent anion include halogen ions such as fluorine ion, chlorine ion, bromine ion and iodine ion, thiocyanate ion, hexafluoroantimonate ion, perchlorate ion, periodate ion, nitrate ion and tetrafluoroboron. Acid ions, hexafluorophosphate ions, molybdate ions, tungstate ions, titanate ions, vanadate ions, phosphate ions, borate ions, and the like. Preferred are perchlorate ions, iodine ions, Tetrafluoroborate ion, hexafluorophosphate ion, hexafluoroantimonate ion and the like can be mentioned.

  Among divalent anions of X, naphthalene-1,5-disulfonic acid, R acid, G acid, H acid, benzoyl H acid, p-chlorobenzoyl H acid, p-toluenesulfonyl H acid, chloro H acid , Chloroacetyl H acid, methanyl γ acid, 6-sulfonaphthyl-γ acid, C acid, ε acid, p-toluenesulfonyl R acid, naphthalene-1,6-disulfonic acid, 1-naphthol-4,8-disulfonic acid Naphthalenedisulfonic acid derivatives, carbonyl J acid, 4,4′-diaminostilbene-2,2′-disulfonic acid, diJ acid, naphthalic acid, naphthalene-2,3-dicarboxylic acid, diphenic acid, stilbene-4 , 4'-dicarboxylic acid, 6-sulfo-2-oxy-3-naphthoic acid, anthraquinone-1,8-disulfonic acid, 1,6-diaminoanthraquinone-2,7-disulfuric acid Acid, 2- (4-sulfophenyl) -6-aminobenzotriazole-5-sulfonic acid, 6- (3-methyl-5-pyrazolonyl) -naphthalene-1,3-disulfonic acid, 1-naphthol-6 And divalent organic acid ions such as (4-amino-3-sulfo) anilino-3-sulfonic acid. Among these anions, preferred are, for example, perchlorate ion, iodine ion, tetrafluoroborate ion, hexafluorophosphate ion, hexafluoroantimonate ion, trifluoromethanesulfonate ion, toluenesulfonate ion, etc. Is mentioned.

Specific examples of the imonium compound are shown below.
(I-1) N, N, N ′, N′-tetrakis (4-di-n-butylaminophenyl) -1,4-benzoquinone-bis (imonium hexafluoroantimonic acid)
(I-2) N, N, N ′, N′-tetrakis (4-di-n-butylaminophenyl) -1,4-benzoquinone-bis (imonium / perchloric acid)
(I-3) N, N, N ′, N′-tetrakis (4-di-amylaminophenyl) -1,4-benzoquinone-bis (imonium hexafluoroantimonic acid)
(I-4) N, N, N ′, N′-tetrakis (4-di-n-propylaminophenyl) -1,4-benzoquinone-bis (imonium hexafluoroantimonic acid)
(I-5) N, N, N ′, N′-tetrakis (4-di-n-hexylaminophenyl) -1,4-benzoquinone-bis (imonium hexafluoroantimonic acid)
(I-6) N, N, N ′, N′-tetrakis (4-di-iso-propylaminophenyl) -1,4-benzoquinone-bis (imonium hexafluoroantimonic acid)
(I-7) 7N, N, N ′, N′-Tetrakis (4-di-n-pentylaminophenyl) -1,4-benzoquinone-bis (imonium hexafluoroantimonic acid)
(I-8) N, N, N ′, N′-tetrakis (4-di-methylaminophenyl) -1,4-benzoquinone-bis (imonium hexafluoroantimonic acid)
The nickel dithiol complex compound can be represented by the following general formula (2).

In the formula, R ₉ , R ₁₀ , R ₁₁ and R ₁₂ are each independently a hydrogen atom, halogen atom, alkyl group, cycloalkyl group, aryl group, hydroxy group, trifluoromethyl group, alkylthio group, arylthio group, A nitro group, a cyano group, an alkoxy group, an aryloxy group, or an alkylamino group is represented. One aromatic ring may have a plurality of substituents, and they may be different from each other.

In R ₉ , R ₁₀ , R ₁₁ and R ₁₂ , the halogen atom, alkyl group, cycloalkyl group, aryl group, alkylthio group, arylthio group, aryloxy group, and alkylamino group include the following. As the halogen atom, for example, fluorine atom, chlorine atom, bromine atom, iodine atom, etc., alkyl, for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, etc., as cycloalkyl group, for example As an aryl group, for example, a phenyl group, a p-nitrophenyl group, an alkylthio group, for example, a methylthio group, an ethylthio group, a butylthio group, etc., an arylthio group, for example, a phenylthio group, Examples of alkoxy groups such as tolylthio group include methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, iso-butoxy group, sec-butoxy group, n-pentyloxy group, iso-pentyloxy As an aryloxy group, for example, Examples of alkylamino groups such as a nonoxy group, 2-methylphenoxy group, 3-methylphenoxy group, 4-methylphenoxy group, naphthoxy group, and the like include, for example, methylamino group, ethylamino group, n-propylamino group, iso-propylamino Group, butylamino group, pentylamino group, hexylamino group, heptylamino group, octylamino group, nonylamino group, benzylamino group, dimethylamino group, diethylamino group, di-n-propylamino group, di-iso-propylamino Group, di-n-butylamino group, di-iso-butylamino group, di-n-pentylamino group, di-iso-pentylamino group, di-n-hexylamino group, di-n-heptylamino group, Di-n-octylamino group, di- (2-ethylhexyl) amino group, dibenzylamino group Arylamino group, diphenylamino group, a ditolylamino group. In the formula, r represents an integer of 1 to 5.

  Preferred specific examples are shown below.

  A preferred phthalocyanine compound for the present invention can be represented by the following general formula (3).

In the formula, each of R ₁₃ to R ₁₆ independently represents a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aryloxy Represents a group, a substituted or unsubstituted alkylthio group, or a substituted or unsubstituted arylthio group. One aromatic ring may have a plurality of substituents, and they may be different from each other. M represents a divalent metal atom, a trivalent or tetravalent substituted metal atom, or an oxy metal.

Examples of R ₁₃ to R ₁₆ include halogen atoms, substituted or unsubstituted alkyl groups, substituted or unsubstituted alkoxy groups, substituted or unsubstituted aryl groups, substituted or unsubstituted aryloxy groups, substituted or unsubstituted Examples of the alkylthio group or the substituted or unsubstituted arylthio group include the following. As a halogen atom, for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. As a substituted or unsubstituted alkyl group, for example, a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group , Iso-butyl group, sec-butyl group, t-butyl group, n-pentyl group, iso-pentyl group, neo-pentyl group, 1,2-dimethyl-propyl group, n-hexyl group, cyclo-hexyl group, 1,3-dimethyl-butyl group, 1-iso-propylpropyl group, 1,2-dimethylbutyl group, n-heptyl group, 1,4-dimethylpentyl group, 2-methyl 1-iso-propylpropyl group, 1 -Ethyl-3-methylbutyl group, n-octyl group, 2-ethylhexyl group, 3-methyl-1-iso-propylbutyl group, 2-methyl-1-iso C1-C20 linear or branched alkyl group such as propyl group, 1-t-butyl-2-methylpropyl group, n-nonyl group, methoxymethyl group, methoxyethyl group, ethoxyethyl group, propoxyethyl group , Alkoxyalkyl groups such as butoxyethyl group, γ-methoxypropyl group, γ-ethoxypropyl group, methoxyethoxyethyl group, ethoxyethoxyethyl group, dimethoxymethyl group, diethoxymethyl group, dimethoxyethyl group, diethoxyethyl group, Alkoxyalkoxyalkyl group, alkoxyalkoxyalkoxyalkyl group, chloromethyl group, 2,2,2-trichloroethyl group, trifluoromethyl group, 2,2,2-trichloroethyl group, 1,1,1,3,3, Halogenated alkyl groups such as 3, -hexafluoro-2-propyl group, Examples of substituted or unsubstituted alkoxy groups such as a ruaminoalkyl group, a dialkylaminoalkyl group, an alkoxycarbonylalkyl group, an alkylaminocarbonylalkyl group, an alkoxysulfonylalkyl group, and the like include, for example, a methoxy group, an ethoxy group, and n-propyloxy Group, iso-propyloxy group, n-butyloxy group, iso-butyloxy group, sec-butyloxy group, t-butyloxy group, n-pentyloxy group, iso-pentyloxy group, neo-pentyloxy group, 1,2- Dimethyl-propyloxy group, n-hexyloxy group, cyclo-hexyloxy group, 1,3-dimethyl-butyloxy group, 1-iso-propylpropyloxy group, 1,2-dimethylbutyloxy group, n-heptyloxy group 1,4-dimethyl Nyloxy group, 2-methyl-1-iso-propylpropyloxy group, 1-ethyl-3-methylbutyloxy group, n-octyloxy group, 2-ethylhexyloxy group, 3-methyl-1-iso-propylbutyloxy Group, 2-methyl-1-iso-propyloxy group, 1-t-butyl-2-methylpropyloxy group, n-nonyloxy group, etc., linear or branched alkoxy group having 1 to 20 carbon atoms, methoxymethoxy group , Methoxyethoxy group, ethoxyethoxy group, propoxyethoxy group, butoxyethoxy group, γ-methoxypropyloxy group, γ-ethoxypropyloxy group, methoxyethoxyethoxy group, ethoxyethoxyethoxy group, dimethoxymethoxy group, diethoxymethoxy group, Dimethoxyethoxy group, diethoxyethoxy group, etc. Alkoxyalkoxyalkoxy groups such as xyalkoxy groups, methoxyethoxyethoxy groups, ethoxyethoxyethoxy groups, butyloxyethoxyethoxy groups, alkoxyalkoxyalkoxyalkoxy groups, chloromethoxy groups, 2,2,2-trichloroethoxy groups, trifluoromethoxy groups , 2,2,2-trichloroethoxy groups, 1,1,1,3,3,3-hexafluoro-2-propyloxy groups and other halogenated alkoxy groups, dimethylaminoethoxy groups, diethylaminoethoxy groups and other alkyl groups Examples of substituted or unsubstituted aryl groups such as aminoalkoxy groups and dialkylaminoalkoxy groups include halogenated fluorine groups such as phenyl, chlorophenyl, dichlorophenyl, bromophenyl, fluorinated phenyl, and iodinated phenyl groups. Examples include an phenyl group, a tolyl group, a xylyl group, a mesityl group, an ethylphenyl group, a methoxyphenyl group, an ethoxyphenyl group, and a pyridyl group. Examples of the substituted or unsubstituted aryloxy group include a phenoxy group, a naphthoxy group, an alkylphenoxy group, etc., and a substituted or unsubstituted alkylthio group such as a methylthio group, an ethylthio group, an n-propylthio group, and an iso-propylthio group. N-butylthio group, iso-butylthio group, sec-butylthio group, t-butylthio group, n-pentylthio group, iso-pentylthio group, neo-pentylthio group, 1,2-dimethyl-propylthio group, n-hexylthio group, Cyclo-hexylthio group, 1,3-dimethyl-butylthio group, 1-iso-propylpropylthio group, 1,2-dimethylbutylthio group, n-heptylthio group, 1,4-dimethylpentylthio group, 2-methyl 1 -Iso-propylpropylthio group, 1-ethyl-3-methylbut Tylthio group, n-octylthio group, 2-ethylhexylthio group, 3-methyl-1-iso-propylbutylthio group, 2-methyl-1-iso-propylthio group, 1-t-butyl-2-methylpropylthio group A linear or branched alkylthio group having 1 to 20 carbon atoms such as n-nonylthio group, methoxymethylthio group, methoxyethylthio group, ethoxyethylthio group, propoxyethylthio group, butoxyethylthio group, γ-methoxypropylthio group Group, γ-ethoxypropylthio group, methoxyethoxyethylthio group, ethoxyethoxyethylthio group, dimethoxymethylthio group, diethoxymethylthio group, dimethoxyethylthio group, diethoxyethylthio group, alkoxyalkylthio group, alkoxyalkoxyalkylthio group , Alkoxyalkoxyalkoxy Sialkylthio group, chloromethylthio group, 2,2,2-trichloroethylthio group, trifluoromethylthio group, 2,2,2-trichloroethylthio group, 1,1,1,3,3,3, -hexafluoro As a substituted or unsubstituted alkylthio group such as a halogenated alkylthio group such as a 2-propylthio group, an alkylaminoalkylthio group such as a dimethylaminoethylsithio group, a diethylaminoethylthio group, a dialkylaminoalkylthio group, and the like, for example, Ethylthio group, n-propylthio group, iso-propylthio group, n-butylthio group, iso-butylthio group, sec-butylthio group, t-butylthio group, n-pentylthio group, iso-pentylthio group, neo-pentylthio group, 1, 2-dimethyl-propylthio group, n-hexylthio , Cyclo-hexylthio group, 1,3-dimethyl-butylthio group, 1-iso-propylpropylthio group, 1,2-dimethylbutylthio group, n-heptylthio group, 1,4-dimethylpentylthio group, 2-methyl 1-iso-propylpropylthio group, 1-ethyl-3-methylbutylthio group, n-octylthio group, 2-ethylhexylthio group, 3-methyl-1-iso-propylbutylthio group, 2-methyl-1- C1-C20 linear or branched alkylthio group such as iso-propylthio group, 1-t-butyl-2-methylpropylthio group, n-nonylthio group, methoxymethylthio group, methoxyethylthio group, ethoxyethylthio Group, propoxyethylthio group, butoxyethylthio group, γ-methoxypropylthio group, γ-ethoxypropylthio group , Alkoxymethoxythio groups such as methoxyethoxyethylthio group, ethoxyethoxyethylthio group, dimethoxymethylthio group, diethoxymethylthio group, dimethoxyethylthio group, diethoxyethylthio group, alkoxyalkoxyalkylthio group, alkoxyalkoxyalkoxyalkylthio group, chloro Methylthio group, 2,2,2-trichloroethylthio group, trifluoromethylthio group, 2,2,2-trichloroethylthio group, 1,1,1,3,3,3-hexafluoro-2-propylthio group Examples of substituted or unsubstituted arylthio groups such as alkylaminoalkylthio groups such as halogenated alkylthio groups, dimethylaminoethylthiothio groups, and diethylaminoethylthio groups, and dialkylaminoalkylthio groups include phenylthio groups and naphthyl groups. Thio, and the like alkylphenylthio group.

Examples of M include the following. Examples of the divalent metal include Cu (II), Zn (II), Co (II), Ni (II), Ru (II), Rh (II), Pd (II), Pt (II), Mn (II ), Mg (II), Ti (II), Be (II), Ca (II), Ba (II), Hg (II), Pb (II), Sn (II), etc. Examples include Al-Cl, Al-Br, Al-F, Al-I, Ga-Cl, Ga-F, Ga-I, Ga-Br, In-Cl, In-Br, In-I, In-F. , Tl-Cl, Tl-Br , Tl-I, Tl-F, Al-C 6 H 5, Al-C 6 H 4 (CH 3), In-C 6 H 5, In-C 6 H 4 (CH ₃ ), In—C ₆ H ₅ , Mn (OH), Mn (OC ₆ H ₅ ), Mn [OSi (CH ₃ ) ₃ ], Fe—Cl, Ru—Cl, etc. CrCl _2, SiCl _2, SiB _{2, SiF 2, SiI 2,} ZrCl 2, GeCl 2, GeBr 2, GeI 2, GeF 2, SnCl 2, SnBr 2, SnF 2, TiCl 2, TiBr 2, TiF 2, Si (OH) 2, Ge (OH ) ₂ , Zr (OH) ₂ , Mn (OH) ₂ , Sn (OH) ₂ , TiR ₂ , CrR ₂ , SiR ₂ , SnR ₂ , GeR ₂ [R is an alkyl group, phenyl group, naphthyl group or derived therefrom Si (OR ′) ₂ , Sn (OR ′) ₂ , Ge (OR ′) ₂ , Ti (OR ′) ₂ , Cr (OR ′) ₂ [R ′ represents an alkyl group, a phenyl group , A naphthyl group, a trialkylsilyl group, a dialkylalkoxysilyl group or a group derived therefrom], Sn (SR ″) ₂ , Ge (SR ″) ₂ (R ″ represents an alkyl group, a phenyl group, a naphthyl group or Derived from them Examples of the oxymetal include VO, MnO, TiO, etc. p represents an integer of 1 to 4. When the substituent is adjacent, 5 or 6 members JP, 2005-145896, A can be referred to for the synthesis method of the compound.

  JP, 2005-145896, A can be referred to for the synthesis method of a phthalocyanine compound. Preferred phthalocyanine compounds are shown below.

  The squalium compound can be represented by the following general formula (4).

In the formula, each of R _{17 to} R ₂₇ independently represents an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, or a heterocyclic group, and these may have a substituent, and m and n are 0 or The integer of 1-6 is represented.

The alkyl group represented by R ₁₇ to R ₂₇ is an alkyl group having 1 to 20 carbon atoms, more preferably 1 to 12 carbons (for example, methyl, ethyl, propyl, butyl, hexyl, undecyl). In addition, a halogen atom (F, Cl, Br), an alkoxycarbonyl group (for example, methoxycarbonyl, ethoxycarbonyl), a hydroxy group, an alkoxy group (for example, methoxy, ethoxy, phenoxy, isobutoxy) or an acyloxy group (for example, acetyloxy, (Butyryloxy, hexyloxy, benzoyloxy), a sulfo group (may be a salt), a carboxyl group (may be a salt) and the like.

Examples of the cycloalkyl group represented by R ₁₇ to R ₂₇ include cyclopentyl and cyclohexyl.

The aryl group represented by R ₁₇ to R ₂₇ preferably has 6 to 12 carbon atoms, and examples thereof include a phenyl group and a naphthyl group. The aryl group may be substituted. Examples of the substituent include alkyl groups having 1 to 8 carbon atoms (for example, methyl, ethyl, butyl), alkoxy groups having 1 to 6 carbon atoms (for example, methoxy, ethoxy), aryloxy groups (for example, phenoxy, p- Chlorophenoxy), halogen atom (F, Cl, Br), alkoxycarbonyl group (eg, methoxycarbonyl, ethoxycarbonyl), amino group (eg, methylamino, acetylamino, methanesulfonamide), cyano group, nitro group, carboxyl Groups (which may be salts) and sulfo groups (which may be salts) are included.

The aralkyl group represented by R ₁₇ to R ₂₇ is preferably an aralkyl group having 7 to 12 carbon atoms (eg, benzyl, phenylethyl) and has a substituent (eg, methyl, methoxy, chloro atom). May be.

Examples of the heterocyclic group represented by R ₁₇ to R ₂₇ include thienyl, furyl, pyrrolyl, pyrazolyl, pyridyl, indolyl and the like. Adjacent substituents may be bonded to each other to form a cyclopentane or cyclohexane ring.

  The compound represented by the general formula (4) may be a mixture. In addition, for this compound, D.C. J. et al. Gravesteijnetal: Optical Storage Media SPIE-420, p327, 1983 can be referred to. Specific examples of preferable squarylium compounds are shown below. Examples of preferred squarylium compounds that are not included in the general formula (4) are also shown.

  Commercially available products as near-infrared absorbing dyes according to the present invention are diimonium compounds such as IRG-022, IRG-040 (these are trade names manufactured by Nippon Kayaku Co., Ltd.), nickel dithiol complex compounds are SIR-128, SIR-130, SIR-132, SIR-159, SIR-152, SIR-162 (these are trade names manufactured by Mitsui Chemicals, Inc.), phthalocyanine compounds are IR-10, IR-12 (above, Nippon Shokubai). (Trade name).

(Binder)
The layer containing the infrared absorbing dye can be formed by using a binder. Examples of the binder used here include polyester resins, polycarbonate resins, nitrocellulose, acrylic resins, polyurethane resins, polyethylene resins, polypropylene resins, polystyrene resins, phenoxy resins, norbornene resins, and epoxy resins. Resins and ultraviolet curable resins are preferable, and polyester resins and acrylic resins are more preferable. The acrylic resin used in the binder of the present invention is preferably a polymer or copolymer containing 10% by mass or more of a (meth) acrylic acid ester unit represented by the following general formula (3).

[Wherein R ₃₁ represents a hydrogen atom or a methyl group, and R ₃₂ represents —C _n H _{2n + 1} (n is an integer of 1 to 10). ]
Examples of these binders include, for example, polymethyl methacrylate, polyethyl methacrylate, polybutyl methacrylate, polymethacrylic acid, polymethyl acrylate, polyethyl acrylate, polybutyl methacrylate, and monomers constituting these polymers. Examples include copolymers with other monomers. Examples of the acrylic resin include Acrypet MD, VH, MF, V (manufactured by Mitsubishi Rayon Co., Ltd.), Hyperl M4003, M-4005, M-4006, M-4202, M-5000, M-5001. , M-4501 (manufactured by Negami Kogyo Co., Ltd.), Dialnal BR-50, BR-52, BR-53, BR-60, BR-64, BR-73, BR-75, BR-77, BR-79, BR-80, BR-82, BR-83, BR-85, BR-87, BR-88, BR-90, BR-93, BR-95, BR-100, BR-101, BR-102, BR- 105, BR-106, BR-107, BR-108, BR-112, BR-113, BR-115, BR-116, BR-117, BR-118 (manufactured by Mitsubishi Rayon Co., Ltd.) Various homopolymers and copolymers were prepared methacrylic monomer as a raw material are commercially available and can also be suitably selecting a preferred resin from the. The above binder may be mixed with other binders. Examples of such binders include water-soluble polymers such as gelatin, polyvinyl alcohol, polyalginic acid (salt), cellulose esters (for example, triacetylcellulose, diacetylcellulose, propionylcellulose, butyrylcellulose, acetylpropionylcellulose, nitro Cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose), polystyrene and polyether ketone and copolymers thereof, polyvinyl alcohol, casein, agar, gum arabic, hydroxyethyl cellulose, cellulose acetate, cellulose acetate butyrate, polyvinyl chloride, polymethacrylic acid And polymers such as polyvinylidene chloride and polyvinyl acetate.

  The polyester resin used in the binder of the present invention is preferably a solvent-soluble polyester. For example, Toyobo Co., Ltd. Byron 103, Byron 200, Byron 300, Byron 630, Unitika Ltd. Elitel UE- 3210, UE-3300, ester resin 100 of Toray Industries, Inc., Sumika Super S200, S300 of Sumitomo Chemical Co., Ltd., and the like. The component of the layer containing the infrared absorbing dye is preferably one that dissolves or swells in the coating solvent of the layer coated thereon. The thickness of the layer containing the infrared absorbing dye is preferably 0.1 μm or more and 15 μm or less, and particularly preferably 0.2 μm or more and 10 μm or less. The layer containing the infrared absorbing dye can be provided by coating with a coating solution containing components constituting the layer containing the infrared absorbing dye. The solvent used when preparing the coating liquid containing the component constituting the layer containing the infrared absorbing dye may be any solvent as long as it can dissolve or disperse each component. Examples include hydrocarbons, alcohols, ketones, esters, and glycol ethers. Two or more of these solvents may be used in combination. For application of the coating solution containing the component constituting the layer containing the infrared absorbing dye, for example, a gravure coater, spinner coater, wire bar coater, roll coater, roll coater, reverse coater, extrusion coater, air doctor coater and the like are known methods. Can be used.

(Near-infrared absorbing layer)
The near-infrared absorbing layer according to the present invention is formed by applying an aqueous coating solution and then drying it. However, the term “aqueous” as used herein means that 30% by mass or more of the solvent (dispersion medium) of the coating solution is water.

  In this invention, it is preferable that 30 to 99 mass% of the solvent of the coating liquid of a near-infrared absorption layer is water.

  As components other than water in the coating solution, water-miscible organic solvents such as methyl alcohol, ethyl alcohol, isopropyl alcohol, methyl cellosolve, ethyl cellosolve, dimethylformamide, and ethyl acetate can be used.

  Specific examples of the solvent composition include the following. Water / methanol = 90/10, water / methanol = 70/30, water / ethanol = 90/10, water / isopropanol = 90/10, water / dimethylformamide = 95/5, water / methanol / dimethylformamide = 80 / 15/5, water / methanol / dimethylformamide = 90/5/5 (however, the number represents mass).

Total binder content of each layer of the near infrared absorbing layer according to the present invention is 0.2 to 30 g / m ² indicates the coating amount per 1 m ^2, more preferably in the range of 1 to 15 g / m ^2. The film thickness per layer of the near-infrared absorbing layer is preferably 0.3 to 50 μm, more preferably 1.5 to 30 μm.

  In the present invention, it is preferable to use a hydrophilic polymer for the binder of the layer containing the near infrared absorbing dye.

(Hydrophilic polymer)
In the present invention, gelatin is most preferable as the hydrophilic polymer. Any gelatin such as lime-processed gelatin or acid-processed gelatin may be used. Further, a gelatin derivative may be used. Further, as a binder, in addition to a hydrophilic polymer, a homo or copolymer latex such as styrene, methyl methacrylate, acrylic acid, butyl acrylate, ethyl acrylate, or the like may be added. These latexes include nonionic groups (polyethylene glycol and acrylic acid esters), anionic groups (for example, monomers having carboxylic acid groups such as itaconic acid and acrylic acid), and sulfonic acid groups (for example, for improving moisture properties). When a monomer having styrenesulfonic acid or N-dimethylsulfopropaneacrylamide is copolymerized in the range of 1 mol% to 20 mol%, water dispersibility can be improved.

(Application method)
For the coating according to the present invention, for example, a known method such as a gravure coater, spinner coater, wire bar coater, roll coater, reverse coater, extrusion coater, air doctor, slide coater can be used. The coating amount is suitably 1 to 100 μm, preferably 10 to 80 μm in terms of wet film thickness. The coating speed is preferably 10 to 100 m / min.

(Layer with a color tone adjustment function that absorbs visible light in a specific wavelength range)
A layer having a color tone adjustment function that absorbs visible light in a specific wavelength range is displayed in blue because the PDP has a characteristic that the phosphor that emits blue light emits red light in addition to blue. There is a problem that a portion to be displayed is displayed in a purplish color, and as a countermeasure against this, it is a layer that corrects colored light and contains a dye that absorbs light at around 595 nm. Specific examples of the dye that absorbs such a specific wavelength include, for example, azo, condensed azo, phthalocyanine, anthraquinone, indigo, perinone, perylene, dioxazine, quinacridone, methine, Well-known organic pigments and organic dyes such as isoindolinone-based, quinophthalone-based, pyrrole-based, thioindigo-based, and metal complex-based materials, and inorganic pigments can be used. Among these, phthalocyanine dyes and anthraquinone dyes are particularly preferable because of good weather resistance.

(Support)
In the present invention, a plastic film, a plastic plate, glass or the like can be used as the support. Examples of raw materials for plastic films and plastic plates include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), vinyl resins such as polyethylene (PE), polypropylene (PP), and polystyrene, and polycarbonate (PC). Triacetyl cellulose (TAC) or the like can be used.

  From the viewpoint of transparency, heat resistance, ease of handling, and price, the plastic film is preferably PET, PEN, or TAC.

  Since the near-infrared absorbing material for display requires transparency, it is desirable that the support has high transparency. In this case, the total visible light transmittance of the plastic film or plastic plate is preferably 70 to 100%, more preferably 80 to 100%, and still more preferably 90 to 100%. Moreover, in this invention, what colored the said plastic film and the plastic board to the extent which does not interfere with the objective of this invention can also be used as a color tone regulator.

(Adhesive)
As the pressure-sensitive adhesive for sticking the near-infrared absorbing material according to the present invention to the PDP, a highly transparent material is preferable. For example, vinyl acetate, epoxy, urethane, ethylene-vinyl acetate, urethane-acrylate, epoxy-acrylate, and the like are preferable. Among these, transparency and colorless epoxy-acrylate and ethylene-vinyl acetate are more preferable. In order to give an antireflection effect to the transparent film in the present invention, silica fine powder, tin oxide, fine powder of titanium oxide are acrylic resin, styrene resin, polyester resin are aromatic hydrocarbons such as toluene, glycol ether, A solution added to a transparent printing ink dissolved in a propylene glycol-based ester organic solvent may be applied to the transparent film. The average particle size of these fine powders is preferably 0.01 to 10 μm, and more preferably, a plurality of types having different particle sizes are mixed. This is to reduce the reflectance of the visual sensation by irregularly reflecting the reflected light by giving the transparent film surface an uneven shape. Next, there is a method of providing a thin layer on a transparent film and utilizing the effects of light reflection and refraction at the interface of the thin layer. That is, when the thickness of the thin layer is λ / 4 (λ: the wavelength of light), the phase of the light of the upper surface reflected light and the lower surface reflected light of the thin layer shifts so as to cancel each other due to interference, and the reflected light. When the refractive index of the thin film is reduced to nf and the refractive index of the transparent film for forming the thin layer is set to nb, nf and nb are raised to the power of 1/2. Apply the principle that the reflection of light is lowest when the values are equal. Therefore, the target of the thickness of the thin layer is ¼ of the wavelength of light that is desired to prevent reflection. That is, the thickness of the thin layer is preferably 0.05 to 0.25 μm. Moreover, when the thin layer 2 is further provided between the transparent film and the thin layer 1, the refractive index of the thin layer 2 is related, and the refractive index of the thin layer 2 is used as nb to prevent reflection by the above calculation method. I can do it. In general, a combination that completely satisfies this condition cannot be obtained, but the refractive index of the thin layer material is required to be as low as possible as that of the transparent film, and the refractive index is 1.28 to 1. It is preferable to use a .45 fluororesin. When the transparent film is polyethylene terephthalate, the refractive index is 1.64, which can be raised as a suitable example. In the case of a cellulose triacetate transparent film, since the refractive index is 1.50, when a fluorine resin is used as a thin layer, a diallyl phthalate resin having a refractive index of 1.59 between the transparent film and the thin layer. It is also possible to provide a layer, a layer of tin oxide having a refractive index of 2.00, or a layer having a refractive index adjusted to 1.59 by mixing tin oxide and an acrylic resin having a refractive index of 1.49. preferable.

(Antistatic performance)
In order to give the transparent film antistatic performance, it is preferable to apply or coat a surfactant. A transparent conductive material such as tin oxide, titanium oxide, or ITO may be added to the printing ink and applied to the transparent film, or may be provided as a thin layer by sputtering or the like. If necessary, after providing a layer of transparent conductive agent on the transparent film mentioned above or applying a printing ink of tin oxide, providing a fluororesin, antistatic performance and antireflection performance Both performances can be provided and are more preferred. The surface conductivity is important for imparting antistatic performance, and the surface resistance is preferably 10 ⁶ Ω to 10 ¹² Ω / □.

(UV absorber)
In addition, when making the color tone correction | amendment layer contain the dye which has a near-infrared absorptivity, any 1 type may be contained among said dye, and 2 or more types may be contained. In order to avoid deterioration of the near-infrared absorbing dye due to ultraviolet rays, it is preferable to use an ultraviolet absorber.

  As the ultraviolet absorber, known ultraviolet absorbers such as salicylic acid compounds, benzophenone compounds, benzotriazole compounds, S-triazine compounds, and cyclic imino ester compounds can be preferably used. Of these, benzophenone compounds, benzotriazole compounds, and cyclic imino ester compounds are preferred. As what is blended with the polyester, a cyclic imino ester compound is particularly preferable.

As a preferable specific example,
(U-1) 2- (2-hydroxy-3,5-di-α-cumyl) -2H-benzotriazole,
(U-2) 5-chloro-2- (2-hydroxy-3-tert-butyl-5-methylphenyl) -2H-benzotriazole,
(U-3) 5-chloro-2- (2-hydroxy-3,5-di-tert-butylphenyl) -2H-benzotriazole,
(U-4) 5-chloro-2- (2-hydroxy-3,5-di-α-cumylphenyl) -2H-benzotriazole,
(U-5) 5-chloro-2- (2-hydroxy-3-α-cumyl-5-tert-octylphenyl) -2H-benzotriazole,
(U-6) 2- (3-tert-butyl-2-hydroxy-5- (2-isooctyloxycarbonylethyl) phenyl) -5-chloro-2H-benzotriazole,
(U-7) 5-trifluoromethyl-2- (2-hydroxy-3-α-cumyl-5-tert-octylphenyl) -2H-benzotriazole,
(U-8) 5-trifluoromethyl-2- (2-hydroxy-5-tert-octylphenyl) -2H-benzotriazole,
(U-9) 5-trifluoromethyl-2- (2-hydroxy-3,5-di-tert-octylphenyl) -2H-benzotriazole,
(U-10) 5-trifluoromethyl-2- (2-hydroxy-3-α-cumyl-5-tert-butylphenyl) -2H-benzotriazole,
(U-11) 2,4-bis (4-biphenylyl) -6- (2-hydroxy-4-octyloxycarbonylethylideneoxyphenyl) -s-triazine,
(U-12) 2,4-Bis (2,4-dimethylphenyl) -6- [2-hydroxy-4- (3-nonyloxy * -2-hydroxypropyloxy) -5-α-cumylphenyl] -s- Triazine (* indicates a mixture of octyloxy group, nonyloxy group and decyloxy group),
(U-13) 2,4,6-tris (2-hydroxy-4-isooctyloxycarbonylisopropylideneoxyphenyl) -s-triazine,
(U-14) hydroxyphenyl-2H-benzotriazole,
(U-15) 2- (2-hydroxy-5-methylphenyl) -2H-benzotriazole,
(U-16) 2- (3,5-di-tert-butyl-2-hydroxyphenyl) -2H-benzotriazole.

(Slip agent)
Examples of slip agents that can be used in the present invention include silicon compounds (for example, dimethylsiloxane polymers), higher fatty acid amides (for example, stearic acid amide, behenic acid amide, arachidic acid amide, etc.), higher fatty acid phthalates (for example, Compounds known in the art such as dilauryl phthalate), esters of higher fatty acids and higher alcohols, and paraffin may be used. Preferred examples of known slip agents include higher aliphatic amides described in US Pat. No. 4,275,146, higher fatty acids or metal salts thereof described in US Pat. No. 3,933,516, and other higher slip agents. Examples thereof include alcohol and derivatives thereof, polyethylene wax, paraffin wax, microcrystalline wax, polyoxyethylene alkylphenyl ether compound and the like. Further, natural oils and fats, waxes, oils such as beeswax can be used in combination. Furthermore, examples of preferable known slip agents that can be used in combination include silicone compounds that are commercially available or can be obtained by synthesis. Even in the case of silicone compounds, polyorganosiloxanes are preferred. For use in these aqueous solutions, it is preferable to add them in the form of a dispersion.

  The slip agent used in the present invention is added to the uppermost layer in the form of a dispersion in an aqueous solution. In this case, other organic solvents can be appropriately selected and contained in the aqueous dispersion. Examples of organic solvents that can be used include ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.), alcohols (lower alcohols having 1 to 8 carbon atoms, such as methyl alcohol, ethyl alcohol, isopropyl alcohol, butyl). Alcohol, hexyl alcohol, octyl alcohol, etc.), glycol derivatives (cellosolve, ethylene glycol diethyl ether, propylene glycol monomethyl ether, etc.), lower fatty acid esters having 1 to 5 carbon atoms (ethyl acetate, butyl acetate, ethyl propionate, etc.) , Haloalkanes (methylene dichloride, ethylene dichloride, trichlene, trichloromethane, trichloroethane, carbon tetrachloride, etc.), hydrocarbons (octane, solventona) Turpentine oil, petroleum ether, thinner, petroleum benzine, benzene, toluene, xylene, etc., phenols (phenol, resorcinol, etc.), ethers (tetrahydrofuran, dioxane, etc.), phosphate esters (trimethyl phosphate, triethyl phosphate, Tributyl phosphate, etc.), amide-based DMF and DMSO. Preferred are alcohols, ketones, glycol derivatives, lower fatty acid esters, haloalkanes, and hydrocarbons. In particular, in a solvent system in which water is mixed and used, it is a solvent selected from alcohols, ketones and glycol derivatives that are water and a uniform solvent. When water is not used, hydrocarbons, ketones , Lower fatty acid esters and haloalkanes are preferred.

In this case, the ratio of water to the organic solvent is 100 to 50: 0 to 50 (volume%), more preferably 100 to 75: 0 to 25 (volume%). As a result, the stability of the dispersion of the slip agent in the aqueous coating solution, the coating property, the smoothness of the resulting coating film, the prevention of adhesion of dust and the like, and the scratch resistance are excellent. In addition, you may use said organic solvent in mixture of 2 or more types with the same or different kind of solvent. The fine dispersion can be obtained by a known dispersion technique, for example, dispersion by mechanical shearing force, ultrasonic dispersion, or precipitation by two-liquid mixing. The amount of slip agent represents the coating amount per 1m ^2, 0.2~500mg / m ^2, more preferably 1 to 300 mg / m ^2. Only 1 type of slipping agent may be used, or 2 or more types may be used together. Since the slipping agent can suppress the generation of scratches when the film is conveyed on the stainless steel roller, the dynamic friction coefficient is preferably 0.3 or less and 0.1 or more. If it is less than 0.1, slipperiness increases. This is not preferable because accurate conveyance becomes difficult. Before the coating solution is applied, it is necessary to remove coarse particles present in the coating solution by filtration. “Filtration” described here is filtration by a filtration filter, and the details of the type and structure of the filtration filter are not particularly limited as long as it is a filtration filter that can remove foreign substances that do not pass through the 2 to 10 μm pore diameter of the present invention. It can be anything. The system for removing coarse particles using these filtration filters is not particularly limited, and is not particularly limited as long as no major problem occurs in filtration.

(Other functional layers)
In the present invention, a functional layer having functionality may be separately provided as necessary. This functional layer can have various specifications for each application. For example, as an electromagnetic shielding material for display, an antireflection layer provided with an antireflection function with an adjusted refractive index or film thickness, a non-glare layer or an antiglare layer (both having a glare prevention function) in a specific wavelength range Layers that have a color tone adjustment function that absorbs visible light, antifouling layers that have the ability to easily remove dirt such as fingerprints, hard-coat layers that are difficult to scratch, layers that have an impact absorption function, and glass scattering when glass is broken A layer having a prevention function or the like can be provided.

  These functional films may be directly bonded to the PDP, or may be bonded to a transparent substrate such as a glass plate or an acrylic resin plate separately from the plasma display panel main body. These functional films can be called optical filters (or simply filters).

  In order to suppress reflection of external light and suppress a decrease in contrast, an antireflection layer provided with an antireflection function contains inorganic substances such as metal oxides, fluorides, silicides, borides, carbides, nitrides and sulfides. , Vacuum deposition method, sputtering method, ion plating method, ion beam assist method, etc., a method of laminating a single layer or a multilayer, such as a method of laminating a resin having different refractive index such as acrylic resin, fluorine resin, etc. There is. Moreover, the film which gave the antireflection process can also be affixed on this filter. In addition, a film that has been subjected to non-glare treatment or anti-glare treatment can be pasted on the filter. Further, if necessary, a hard coat layer can be provided.

[Example 1]
Hereinafter, the present invention will be described more specifically with reference to examples of the present invention.

《Comparative example》
(Preparation of Sample-100)
[Preparation of Support 1]
One side of a transparent polyethylene terephthalate film base (thickness: 100 μm) is subjected to a corona discharge treatment of 0.5 kV · A · min / m ² , and then subtracted using the following undercoat coating solution A Layer A was applied to a dry film thickness of 0.2 μm. Furthermore, after the other surface was similarly subjected to a corona discharge treatment of 0.5 kV · A · min / m ² , the following undercoating liquids B and A were used to form the undercoating layers B and A. These were coated so that the dry film thicknesses were 0.1 μm and 0.2 μm, respectively. After that, heat treatment was performed at 130 ° C. for 15 minutes in a heat treatment oven having a film transport device composed of a plurality of roll groups, and Support-1 was produced.

<Undercoat coating liquid A>
270 g of copolymer latex liquid (solid content 30%) of 40% by mass of butyacrylate, 10% by mass of t-butyl acrylate, 25% by mass of styrene, and 25% by mass of 2-hydroxyethyl acrylate and compound (UL-1) 0 .6 g and 1 g of polyvinyl alcohol having a saponification degree of 80% were mixed. Furthermore, 1.3 g of silica particles (Syloid 350, manufactured by Fuji Silysia) was previously ultrasonically dispersed in 100 g of water (manufactured by Alex Corporation, trade name: Ultrasonic Generator, frequency 25 kHz, 600 W). The liquid which had been dispersed for 30 minutes was added, and finally it was made up to 1000 ml with water to obtain an undercoat coating liquid A-1.

<Synthesis of colloidal tin oxide dispersion>
65 g of stannic chloride hydrate was dissolved in 2000 ml of a water / ethanol mixed solution to obtain a uniform solution. This was then boiled to obtain a coprecipitate. The produced precipitate is taken out by decantation and washed with distilled water many times. After confirming that there is no reaction of chlorine ions by dropping silver nitrate into the distilled water from which the precipitate has been washed, distilled water is added to the washed precipitate to make a total volume of 2000 ml. Further, 40 ml of 30% aqueous ammonia was added and heated in an aqueous solution, and then further heated and concentrated to 470 ml to obtain a colloidal tin oxide dispersion.

<Undercoat coating solution B>
37.5 g of SnO ₂ sol synthesized by the synthesis of the colloidal tin oxide dispersion, 10% by mass of n-butyl acrylate, 35% by mass of t-butyl acrylate, 27% by mass of styrene and 28% by mass of 2-hydroxyethyl acrylate Copolymer latex liquid (solid content 30%) 3.7 g, n-butyl acrylate 40 mass%, styrene 20 mass%, glycidyl methacrylate 40 mass% copolymer latex liquid (solid content 30%) 14.8 g and coating Surfactant UL-1 0.1g was mixed as an auxiliary agent, and it was finished to 1000 ml with water, and was used as undercoat coating liquid B-1.

  (Preparation of coating solution (C-0) for near-infrared absorbing dye layer)

  After dissolving 20 g of polyvinyl butyral powder (BL-5Z, manufactured by Sekisui Chemical Co., Ltd.) in 80 g of methyl ethyl ketone at room temperature, infrared absorbing dye F-10.04 g was added with stirring, and a near infrared absorbing dye layer coating solution C-0. Was prepared.

(Preparation of near-infrared absorption filter (sample-100))
The near-infrared absorbing dye layer coating solution C-0 is applied to the side on which the undercoat layers B and A of the support-1 are applied with a blade coater having a wet film thickness of 100 μm, and dried at 55 ° C. for 30 minutes. Sample-100 was prepared.

<< Examples according to the present invention >>
(Preparation of support-2)
After both sides of a transparent biaxially stretched polyethylene terephthalate film having a thickness of 100 μm as a support are subjected to 100 W / m ² · min corona treatment, the refractive index is 1.55, the elastic modulus is 100 MPa at 25 ° C., and the glass transition temperature is 37 ° C. on one side. A latex (made by Nippon Zeon Co., Ltd., X407C5) made of styrene-butadiene copolymer was applied to a thickness of 300 nm to form an undercoat layer. On this undercoat layer, an acrylic latex (HA16, manufactured by Nippon Acrylic Co., Ltd.) having a refractive index of 1.50, an elastic modulus of 120 MPa at 25 ° C., and a glass transition temperature of 50 ° C. is dried to a thickness of 80 nm. This was applied to form a second undercoat layer. Further, after the other surface is similarly subjected to a corona discharge treatment of 0.5 kV · A · min / m ² , the above-described undercoat coating solutions B and A are used to form the undercoat layers B and A. These were coated so that the dry film thicknesses were 0.1 μm and 0.2 μm, respectively. Thereafter, heat treatment was performed at 130 ° C. for 15 minutes in a heat treatment oven having a film transport device composed of a plurality of roll groups, and Support-2 was produced.

(Preparation of Infrared Absorbing Dye Dispersion (B-1))
After 0.6 g of tricresyl phosphate was dissolved in 1.4 g of ethyl acetate, infrared absorbing dye F-1 0.3 was further added and dissolved by stirring. In a separate container, 13 g of pure water, 1.5 g of gelatin, and 2.6 g of a 10% isopropyl naphthalenesulfonic acid solution were added and dissolved.

  The solution of the infrared dye was added to the gelatin solution with stirring over 1 minute, and then ultrasonic dispersion was performed for 10 minutes while cooling with water to prepare a polymer dispersion B-1.

(Preparation of coating solution (C-1) for near-infrared absorbing dye layer)
After 7.85 g of gelatin was dissolved in 91.2 g of pure water at 40 ° C., 1.8 g of the oil dispersion B-2 was added, 1% dichloro-hydroxytriazine solution (1.3 g) was added, A coating liquid C-1 was prepared.

(Preparation of near-infrared absorption filter (sample-101))
The near-infrared absorbing dye layer coating solution C-1 was applied to the side of the support-2 coated with the styrene-butadiene copolymer with a blade coater having a wet film thickness of 100 μm, and dried at 50 ° C. for 30 minutes. 101 was produced. O / G (ratio of high boiling point solvent and binder) of this sample is 0.007 (Preparation of dispersion of infrared absorbing dye (B-2))
After 0.2 g of tricresyl phosphate was dissolved in 0.5 g of ethyl acetate, infrared absorbing dye F-1 0.03 was further added and dissolved by stirring.

  In a separate container, 4.5 g of pure water, 0.5 g of gelatin, and 0.95 g of a 10% isopropyl naphthalene sulfonic acid solution were added and dissolved.

  The infrared dye solution was added to the gelatin solution with stirring over 1 minute, and then ultrasonic dispersion was performed for 10 minutes while cooling with water to prepare a polymer dispersion B-2.

(Preparation of coating solution (C-2) for near-infrared absorbing dye layer)
After 7.5 g of gelatin was dissolved in 87 g of pure water at 40 ° C., 6.3 g of the above oil dispersion B-2 was added, 1% dichloro-hydroxytriazine solution (1.3 g) was added, and the coating solution C-2 was prepared.

(Preparation of near-infrared absorption filter (sample-102))
The near-infrared absorbing dye layer coating solution C-2 was applied to the side of the support-2 coated with the styrene-butadiene copolymer with a blade coater having a wet film thickness of 100 μm, and dried at 50 ° C. for 30 minutes. 102 was produced. The O / G (the ratio of the high boiling point solvent to the binder) of this sample is 0.025.

(Preparation of Infrared Absorbing Dye Dispersion (B-3))
After dissolving 0.56 g of tricresyl phosphate in 1.4 g of ethyl acetate, infrared absorbing dye F-10.03 was further added and dissolved by stirring. In another container, 12.7 g of pure water, 1.5 g of gelatin, and 2.65 g of a 10% solution of isopropylnaphthalenesulfonic acid were added and dissolved.

  The solution of the infrared dye was added to the gelatin solution with stirring over 1 minute, and then ultrasonic dispersion was performed for 10 minutes while cooling with water to prepare a polymer dispersion B-3.

(Preparation of coating solution (C-3) for near-infrared absorbing dye layer)
After 6.5 g of gelatin was dissolved in 76.5 g of pure water at 40 ° C., 17.5 g of the above oil dispersion B-3 was added, 1% dichloro-hydroxytriazine solution (1.3 g) was added, Coating liquid C-3 was prepared.

(Preparation of near-infrared absorption filter (sample-103))
The near-infrared absorbing dye layer coating solution C-2 was applied to the side of the support-2 coated with the styrene-butadiene copolymer with a blade coater having a wet film thickness of 100 μm, and dried at 50 ° C. for 30 minutes. 102 was produced. The O / G (the ratio of the high boiling point solvent and the binder) of this sample is 0.07.

(Preparation of Infrared Absorbing Dye Dispersion (B-4))
After dissolving 1.05 g of tricresyl phosphate in 2.6 g of ethyl acetate, infrared absorbing dye F-10.03 was further added and dissolved by stirring.

  In a separate container, 24 g of pure water, 2.8 g of gelatin, and 4.9 g of a 10% isopropyl naphthalene sulfonic acid solution were added and dissolved.

  The solution of the infrared dye was added to the gelatin solution with stirring for 1 minute, and then ultrasonic dispersion was performed for 10 minutes with water cooling to prepare a polymer dispersion B-4.

(Preparation of coating solution (C-4) for near-infrared absorbing dye layer)
After dissolving gelatin (5.2 g) in pure water (63 g) at 40 ° C., 33 g of the oil dispersion B-2 was added, dichloro-hydroxytriazine 1% solution (1.3 g) was added, and coating solution C- 4 was prepared.

(Preparation of near-infrared absorption filter (sample-104))
The near-infrared absorbing dye layer coating solution C-4 was applied to the side of the support-2 coated with the styrene-butadiene copolymer with a blade coater having a wet film thickness of 100 μm, dried at 50 ° C. for 30 minutes, and sample − 104 was produced. The O / G (ratio of high boiling point solvent and binder) of this sample is 0.13.

(Preparation of dispersion of infrared absorbing dye (B-5))
After dissolving 2.95 g of tricresyl phosphate in 7.4 g of ethyl acetate, 0.03 infrared absorbing dye F-1 was further added and dissolved by stirring.

  In a separate container, 67 g of pure water, 8 g of gelatin, and 14 g of a 10% solution of isopropylnaphthalenesulfonic acid were added and dissolved.

  The solution of the infrared dye was added to the gelatin solution with stirring over 1 minute, and then ultrasonic dispersion was performed for 10 minutes while cooling with water to prepare a polymer dispersion B-5.

(Preparation of coating solution (C-5) for near-infrared absorbing dye layer)
A dichloro-hydroxytriazine 1% solution (1.3 g) was added to 92 g of the oil dispersion B-5 to prepare a coating solution C-5.

(Preparation of near-infrared absorption filter (sample-105))
The near-infrared absorbing dye layer coating solution C-5 was applied to the side of the support-2 coated with the styrene-butadiene copolymer with a blade coater having a wet film thickness of 100 μm and dried at 50 ° C. for 30 minutes. 105 was produced. The O / G (the ratio of the high boiling point solvent and the binder) of this sample is 0.37.

(Preparation of dispersion of infrared absorbing dye (B-6))
After dissolving 1.05 g of tricresyl phosphate in 2.6 g of ethyl acetate, 0.5 g of infrared absorbing dye F-10.03 and immonium dye IRG-022 (manufactured by Nippon Kayaku) are added and dissolved by stirring. did.

  In a separate container, 24 g of pure water, 2.8 g of gelatin, and 4.9 g of a 10% isopropyl naphthalene sulfonic acid solution were added and dissolved.

  The infrared dye solution was added to the gelatin solution with stirring over 1 minute, and then ultrasonic dispersion was performed for 10 minutes while cooling with water to prepare a polymer dispersion B-6.

(Preparation of coating solution (C-6) for near-infrared absorbing dye layer)
After dissolving 5.2 g of gelatin in 63 g of pure water at 40 ° C., 33 g of the above oil dispersion B-6 was added, 1% dichloro-hydroxytriazine solution (1.3 g) was added, and coating solution C- 6 was prepared.

(Preparation of near-infrared absorption filter (sample-106))
The near-infrared absorbing dye layer coating solution C-6 was applied to the side of the support-2 coated with the styrene-butadiene copolymer with a blade coater having a wet film thickness of 100 μm, and dried at 50 ° C. for 30 minutes. 106 was produced. The O / G (ratio of high boiling point solvent and binder) of this sample is 0.13.

(Evaluation of light resistance)
The obtained samples -100 to 105 were cut into a size of 3.5 cm × 5 cm, the spectral absorption was measured with a Hitachi spectrophotometer U-4100, and the average absorbance in the near infrared region of 800 to 1100 nm was calculated. . In the light resistance deterioration test, a super xenon weather meter SX75 manufactured by Suga Test Instruments Co., Ltd. was used, and the relative humidity was 50%, the irradiation intensity was 50 W / square meter, and the rate of absorption deterioration after 100 hours test was evaluated. The evaluation results are shown in Table 1.

(Evaluation of heat and humidity resistance)
The obtained samples -100 to 105 were cut into a size of 3.5 cm × 5 cm, the spectral absorption was measured with a Hitachi spectrophotometer U-4100, and the average absorbance in the near infrared region of 800 to 1100 nm was calculated. . Thereafter, the sample was stored in a dark place at 60 ° C. and 90% for 500 hours, and the rate of absorption deterioration was evaluated. The evaluation results after storage are shown in Table 1.

(Evaluation of heat resistance)
The obtained samples -100 to 105 were cut into a size of 3.5 cm × 5 cm, the spectral absorption was measured with a Hitachi spectrophotometer U-4100, and the average absorbance in the near infrared region of 800 to 1100 nm was calculated. . Thereafter, the sample was stored in a dark place in an environment of 80 ° C. (humidity was expected) for 500 hours, and the rate of absorption deterioration was evaluated. The evaluation results after storage are shown in Table 1.

(Evaluation of sweating)
The obtained samples -100 to 105 were cut into a size of 3.5 cm × 5 cm, stored in a dark place in an environment of 80 ° C. (humidity is expected) for 100 hours, and then visually evaluated based on the following evaluation criteria. did.

  Rank 5 Before and after storage, there was no change on the surface of the coating film, and no sweating was observed.

  Rank 4 Sweating is slightly observed on the coating surface.

  3rd level Sweating is observed, but it is almost unnoticeable.

  Rank 2 A level where sweating is observed and sticks to the finger when rubbed with the finger.

  Rank 1 Strong sweating is observed.

  The results of the various evaluations are summarized in Table 1.

From Table 1, it can be seen that the sample according to the present invention is superior to the comparative example in the above evaluation. That is,
[Example 2]
(Application to front filter for plasma display as infrared shielding filter)
The optical filter affixed to the front surface of the Pioneer plasma display (PDP-435HDL) was peeled off, white display was performed, and the infrared emission spectrum was measured with an Ocean Optics ultra-small spectrometer USB2000, 820 nm, 880 nm, A strong peak was observed at 980 nm. Thereafter, Sample-104 (30 cm × 30 cm) was affixed to the panel surface, and the same measurement was performed with USB2000. As a result, it was confirmed that all infrared emission spectra had disappeared.

Claims (6)

In a method for producing a near-infrared absorbing filter comprising a near-infrared absorbing layer coated on a transparent support, a coating solution containing a near-infrared absorbing dye in which the near-infrared absorbing layer is dispersed in a high-boiling solvent is applied on the support. A method for producing a near-infrared absorbing filter, which is formed by applying to a substrate and drying by heating. The method for producing a near-infrared absorbing filter according to claim 1, wherein 30% by mass or more and 99% by mass or less of the solvent of the coating solution for the near-infrared absorbing layer is water. The method for producing a near-infrared absorbing filter according to claim 1 or 2, wherein the content of the high boiling point solvent is 1 to 30% by mass of the total amount of the binder in the near-infrared absorbing layer. The said near-infrared absorption layer contains at least 1 type of compound chosen from a diimonium compound, a nickel dithiol compound, a phthalocyanine-type compound, a squarylium compound, and a croconium compound as said near-infrared absorptive dye. The manufacturing method of the near-infrared absorption filter as described in any one of these. The near-infrared absorption filter manufactured by the manufacturing method as described in any one of Claims 1-4. 6. A front filter for plasma display, comprising the near-infrared absorption filter according to claim 5.