JP2020158367A - Near-infrared ray absorbing material, near-infrared ray absorbing layer and near-infrared ray absorbing member - Google Patents

Abstract

To provide a near-infrared ray absorbing particle having reduced bluish color, to provide a powder composed of the near-infrared ray absorbing particles, to provide a dispersion liquid including the powder, to provide a resin composition including the powder, to provide a near-infrared ray absorbing layer including the powder and to provide a near-infrared ray absorbing member including the powder.SOLUTION: The near-infrared ray absorbing particle has a composition represented by formula (I) as given below: (I): CspMqW1-qOr [in the formula, M represents one kind or two or more kinds of elements selected from the group consisting of Nb, Ta, Al and Sc; p satisfies 0.01≤p<0.3; q satisfies 0.01≤q<0.5; and q and r satisfy 3<r/(1-q)].SELECTED DRAWING: None

Description

The present invention relates to near-infrared absorbing materials (near-infrared absorbing particles, powders composed of the near-infrared absorbing particles, dispersions containing the powders, resin compositions containing the powders, etc.) and the near-infrared rays. The present invention relates to a near-infrared absorbing layer and a near-infrared absorbing member obtained by using an infrared absorbing material.

Tungsten-based materials, LaB ₆ , ATO, ITO and the like are generally known as near-infrared absorbing materials, but the following techniques are known as tungsten-based materials. In other words, the general _{formula: M X A Y W (1-} Y) O 3 [ wherein, M represents H, the He, alkali metals, one or more elements selected from alkaline earth metals such as, A is , Mo, Nb, Ta and the like, W represents tungsten, O represents oxygen, X represents a number satisfying 0 <X≤1.2, and Y represents Represents a number that satisfies 0 <Y ≦ 1. ], Composite oxide fine particles represented by [Patent Document 1], general formula: M _x W _{y Oz} [In the formula, M is one or more selected from H, He, alkali metal, alkaline earth metal, etc. W represents tungsten, O represents oxygen, and x, y and z represent numbers satisfying 0.001 ≦ x / y ≦ 1 and 2.2 ≦ z / y ≦ 3.0. .. ], The composite tungsten oxide fine particles (Patent Document 2) and the like are known.

It is described that the near-infrared absorbing particles described in Patent Documents 1 and 2 largely absorb light in the near-infrared region, particularly in the vicinity of a wavelength of 1000 nm, and therefore the transmitted color tone is bluish. Here, since bluishness affects visibility, there is a demand to reduce it as much as possible.

Japanese Unexamined Patent Publication No. 2006-299086 WO2005 / 037932

The present invention includes near-infrared absorbing particles having reduced bluish tint, a powder composed of the near-infrared absorbing particles, a dispersion liquid containing the powder, a resin composition containing the powder, and the powder. It is an object of the present invention to provide a near infrared ray absorbing layer and a near infrared ray absorbing member containing the powder.

The present invention has the following formula (I):
Cs _p M _q W _{1-q Or} ... (I)
[During the ceremony,
M represents one or more elements selected from the group consisting of Nb, Ta, Al and Sc.
p satisfies 0.01 ≦ p <0.3 and
q satisfies 0.01 ≦ q <0.5 and
q and r satisfy 3 <r / (1-q). ]
Provided are near-infrared absorbing particles having a composition represented by.

In addition, the present invention comprises a powder composed of the near-infrared absorbing particles of the present invention, a dispersion containing the powder, a resin composition containing the powder, a near-infrared absorbing layer containing the powder, and , Provide a near-infrared absorbing member containing the powder.

According to the present invention, near-infrared absorbing particles having reduced bluish tint, a powder composed of the near-infrared absorbing particles, a dispersion liquid containing the powder, a resin composition containing the powder, and the powder. A near-infrared absorbing layer containing the above and a near-infrared absorbing member containing the powder are provided.

Hereinafter, the present invention will be described in detail.

<Particles and powders>
The particles and powders of the present invention have near infrared absorption. The wavelength of near infrared rays that can be absorbed by the particles and powder of the present invention is usually 780 nm or more and 2500 nm or less.

The powder of the present invention is composed of the particles of the present invention. The particles of the present invention constituting the powder of the present invention may be one kind or two or more kinds. The powder of the present invention may contain particles other than the particles of the present invention (for example, near-infrared absorbing particles other than the particles of the present invention), but is preferably composed of the particles of the present invention.

The particles and powders of the present invention have the following formula (I):
Cs _p M _q W _{1-q Or} ... (I)
It has a composition represented by.

In formula (I), Cs represents cesium, W represents tungsten, and O represents oxygen.

In formula (I), M represents one or more elements selected from the group consisting of Nb, Ta, Al and Sc. Nb represents niobium, Ta represents tantalum, Al represents aluminum, and Sc represents scandium. When M represents one element, the one element represented by M is preferably Nb, Al or Sc, and more preferably Nb or Al. When M represents two or more elements, the two or more elements represented by M preferably include two or more selected from Nb, Al and Sc, and more preferably Nb and Al.

In formula (I), p represents a number satisfying 0.01 ≦ p <0.3. The number represented by p preferably satisfies 0.1 ≦ p <0.3, more preferably 0.15 ≦ p <0.3, and even more preferably 0.2 ≦ p <0.3.

In formula (I), q represents a number satisfying 0.01 ≦ q <0.5. The number represented by q preferably satisfies 0.05 ≦ q <0.5, more preferably 0.1 ≦ q <0.5, and even more preferably 0.1 ≦ q ≦ 0.3.

In formula (I), q and r represent numbers that satisfy 3 <r / (1-q). The numbers represented by q and r are preferably 3.05 ≦ r / (1-q), more preferably 3.1 ≦ r / (1-q), and even more preferably 3.3 ≦ r / (. 1-q) is satisfied.

In the formula (I), the number represented by r preferably satisfies 2.7 ≦ r ≦ 3.0, more preferably 2.8 ≦ r ≦ 3.0.

The particles and powders of the present invention have a reduced bluish tint by having a composition represented by the formula (I). As the index of bluish tint, the L ^* value and b ^* value of the L ^* a ^* b ^* color system can be used. The L ^* a ^* b ^* color system L ^* value and b ^* value will be described later.

Hereinafter, the characteristics of the particles and powders of the present invention (L ^* a ^* b ^* color system L ^* and b ^* values, crystal structure, average particle size, BET specific surface area, etc.) will be described. The particles and powders of the present invention can have two or more of the properties described herein.

When a resin layer containing the resin and the powder of the present invention dispersed in the resin is formed and the L ^* a ^* b ^* color system L ^* value and b ^* value of the resin layer are measured, L ^*. The value is preferably 85 or more and 97 or less, more preferably 85 or more and 95 or less, still more preferably 85 or more and 93 or less, and the b ^* value is preferably -2 or more and 7 or less, still more preferably -1 or more and 5 or less. , Even more preferably −0.5 or more and 4.5 or less. Since the particles and powders of the present invention have a reduced bluish tint, such L ^* and b ^* values can be realized.

The L ^* a ^* b ^* color system means the color system standardized by the CIE (Commission Internationale de l'Eclairage) and adopted in JIS Z 8781-4: 2013.

Preferable embodiments of the method for measuring the L ^* value and the b ^* value of the L ^* a ^* b ^* color system are as follows. A mixture containing 20% by weight of the powder of the present invention, 75% by weight of 2-butanone, and 5% by weight of the dispersant is prepared. A media dispersion treatment using a paint shaker is performed on this mixture to prepare a dispersion liquid. A coating material containing 10% by weight of this dispersion, 10% by weight of a thermosetting resin, and 80% by weight of 2-butanone is prepared. This paint is applied on a polyethylene terephthalate (PET) film with a bar coater to form a coating film (thickness 3 μm), dried at 80 ° C. for 10 minutes to evaporate the solvent, and a resin layer is formed on the PET film. Next, using a color difference meter (for example, CM-2600d manufactured by Konica Minolta), a pulse xenon lamp is irradiated from the resin layer surface side at an incident angle of 0 degrees (the normal direction of the resin layer surface is 0 degrees). , L ^* value and b ^* value are measured based on the SCI method. The L ^* and b ^* values are measured at any 10 points, and the average value of the L ^* values at 10 points and the average value of the b ^* values at 10 points are taken as the L ^* value and b ^* value of the powder, respectively. To do.

The particles of the present invention preferably have a crystal structure. Examples of the crystal structure include hexagonal crystals, tetragonal crystals, and cubic crystals. When the particles of the present invention do not have a hexagonal crystal structure, the b ^* value of the L ^* a ^* b ^* color system tends to decrease significantly. Therefore, it is preferable that the particles of the present invention have a hexagonal crystal structure from the viewpoint of adjusting the b ^* value of the L ^* a ^* b ^* color system to a desired range and realizing a reduced bluish tint.

The crystal structure is sampled by Cu Kα rays generated by filling a sample in a dedicated glass holder and applying a voltage-current of 50 kV-300 mA using an X-ray diffractometer (RINT-TTRIII manufactured by Rigaku). It can be confirmed by measuring under the conditions of an angle of 0.02 ° and a scanning speed of 4.0 ° / min, performing an analysis with the XRD analysis software JADE using the measurement results, and identifying the crystal structure.

The average particle size of the powder of the present invention can be measured by, for example, a dynamic light scattering method. The average particle size of the powder of the present invention measured by the dynamic light scattering method means a particle size in which the cumulative volume is 50% in the volume-based particle size distribution obtained by the dynamic light scattering method.

A preferred embodiment of the method for measuring the average particle size by the dynamic light scattering method is as follows. A mixture containing 20% by weight of the powder of the present invention, 75% by weight of 2-butanone, and 5% by weight of the dispersant is prepared. A media dispersion treatment using a paint shaker is performed on this mixture to prepare a dispersion liquid. The dispersion is diluted to a concentration of 1/10, and the average particle size of the powder contained in the diluent is measured using, for example, Malvern Panasonic's "Zetasizer Nano ZS" as a measuring device.

In the above embodiment, the average particle size of the powder of the present invention measured by the dynamic light scattering method is preferably 150 nm or less, more preferably 150 nm or less, from the viewpoint of maintaining transparency when used as a near-infrared absorbing member. It is 125 nm or less, and even more preferably 100 nm or less. The lower limit is not particularly limited, but is preferably 10 nm, more preferably 20 nm, and even more preferably 30 nm.

The average particle size of the powder of the present invention can be measured by, for example, the small-angle X-ray scattering method. The average particle size of the powder of the present invention measured by the small-angle X-ray scattering method means a particle size in which the cumulative volume is 50% in the volume-based particle size distribution obtained by the small-angle X-ray scattering method.

A preferred embodiment of the method for measuring the average particle size by the small-angle X-ray scattering method is as follows. Prepare the same dispersion as the dispersion prepared for the measurement of the average particle size by the dynamic light scattering method described above. A coating material containing 10% by weight of this dispersion, 10% by weight of acrylic resin, and 80% by weight of 2-butanone is prepared. This paint is applied on a polyethylene terephthalate (PET) film with a bar coater to form a coating film (thickness 3 μm), and dried at 80 ° C. for 10 minutes to evaporate the solvent to form a resin layer. The average particle size of the powder contained in the resin layer is measured by the following apparatus.

In order to obtain the small-angle X-ray scattering profile, the small-angle X-ray scattering specification is applied as an optical system to the fully automatic multipurpose X-ray diffractometer SmartLab manufactured by Rigaku Co., Ltd., and the small-angle X-ray scattering profile of the sample is measured by the transmission method. .. A Cu target is used as the X-ray source and a scintillation counter is used as the detector. Next, assuming that the X-ray small-angle scattering profile of the sample has a spherical particle shape and the variation in particle size is given by the gamma distribution function, profile analysis is performed using the analysis software NANO-Solver manufactured by Rigaku Co., Ltd. To do. The target angle range for profile analysis is up to 2θ = 4 deg.

In the above embodiment, the average particle size of the powder of the present invention measured by the small-angle X-ray scattering method is preferably 200 nm or less, more preferably 200 nm or less, from the viewpoint of maintaining transparency when used as a near-infrared absorbing member. It is 100 nm or less, and even more preferably 40 nm or less. The lower limit is not particularly limited, but is preferably 5 nm, more preferably 10 nm, and even more preferably 15 nm.

The BET specific surface area of the powder of the present invention is not particularly limited, and can be appropriately adjusted according to the intended use. From the viewpoint of reducing the average particle size and improving the transparency, it is preferable that the powder of the present invention has a large BET specific surface area.

The BET specific surface area of the powder of the present invention is preferably 10 m ² / g or more, more preferably 12 m ² / g or more, and even more preferably 14 m ² / g or more. The upper limit is not particularly limited, but is preferably 100 m ² / g, more preferably 70 m ² / g, even more preferably 50 m ² / g, and even more preferably 30 m ² / g.

The BET specific surface area of the powder of the present invention is measured according to "(3.5) One-point method" in "6.2 Flow method" of JIS R1626 "Method for measuring specific surface area of fine ceramic powder by gas adsorption BET method". To. As the gas, a nitrogen-helium mixed gas containing 30% by volume of nitrogen as an adsorbed gas and 70% by volume of helium as a carrier gas is used. As the measuring device, "BELSORP-MR6" manufactured by Microtrack Bell is used.

The powder of the present invention can be produced by heat-treating a raw material in an atmosphere containing an inert gas and / or a reducing gas.

The raw material is not particularly limited as long as it contains cesium, tungsten and M element. The raw material is, for example, a mixture of a compound containing cesium, a compound containing tungsten, and a compound containing M element. The compound used as a raw material may be a compound containing two or more of cesium, tungsten and M element. Compounds used as raw materials include, for example, oxides containing one or more of cesium, tungsten and M element, oxide hydrates, chlorides, ammonium salts, carbonates, nitrates and sulfuric acid. Examples thereof include salts, oxalates, hydroxides and peroxides. Of these, oxides, carbonates, hydrates and the like do not generate impurities that are difficult to remove during heat reduction, and are therefore suitable for industrial production methods. The compound containing cesium is preferably a carbonate of cesium. The compound containing tungsten is preferably an oxide of tungsten. The compound containing the M element is preferably an oxide of the M element. Further, the raw material may contain additives such as a sintering inhibitor and a reduction aid.

The raw material is blended with the composition represented by the formula (I) and then heat-treated in an atmosphere containing an inert gas and / or a reducing gas. Examples of the inert gas include argon gas, nitrogen gas and the like, and examples of the reducing gas include hydrogen gas, ammonia gas and the like. When hydrogen gas is used as the reducing gas, the amount of hydrogen gas in the atmosphere is preferably 0.1 to 100% by volume, more preferably 1 to 10% by volume. The heat treatment temperature is preferably 400 to 1000 ° C., further preferably 450 to 900 ° C., even more preferably 500 to 800 ° C., and the heat treatment time is preferably 1 to 20 hours.

In one embodiment, the raw material is calcined at 400-600 ° C. for 1-20 hours in an atmosphere of an inert gas and a reducing gas, and then calcined at 600-900 ° C. for 1-20 hours in an atmosphere of an inert gas. .. The fired product obtained by the heat treatment is pulverized, if necessary.

<Dispersion>
The dispersion liquid of the present invention contains a dispersion medium and the powder of the present invention dispersed in the dispersion medium.

The amount of the powder of the present invention contained in the dispersion liquid of the present invention is not particularly limited, and can be appropriately adjusted according to the use of the dispersion liquid of the present invention and the like. The dispersion liquid of the present invention has various viscosities depending on the content of the powder of the present invention, and takes various forms such as ink, slurry, and paste depending on the viscosity. The amount of the powder of the present invention contained in the dispersion liquid of the present invention is preferably 0.1 to 95% by mass, more preferably 1 to 80% by mass, further more based on the total mass of the dispersion liquid of the present invention. It is preferably 1 to 50% by mass.

The dispersion medium contained in the dispersion liquid of the present invention is not particularly limited as long as it is a liquid capable of dispersing the powder of the present invention. Examples of the dispersion medium include water, an organic solvent and the like. The dispersion medium may be one kind of solvent or a mixture of two or more kinds of solvents. Examples of the mixture of two or more kinds of solvents include a mixture of water and one kind or two or more kinds of organic solvents, and a mixture of two or more kinds of organic solvents. The dispersion medium preferably contains an organic solvent. Specific examples of the organic solvent include the following.

Alcohols: For example, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, cyclohexanol, 1-heptanol, 1-octanol, 1-nonanol, 1-decanol, glycidol, benzyl alcohol, methylcyclohexanol, 2 -Methyl-1-butanol, 3-methyl-2-butanol, 4-methyl-2-pentanol, 2-propanol, 2-ethylbutanol, 2-ethylhexanol, 2-octanol, 2-methoxyethanol, 2-ethoxy Ethanol, 2-n-butoxyethanol, 2-phenoxyethanol and the like.

Polyhydric alcohols: For example, ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tetraethylene glycol and the like.

Polyhydric alcohol alkyl ether: For example, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, Propylene glycol monobutyl ether, etc.

Polyhydric alcohol aryl ether: For example, ethylene glycol monophenyl ether and the like.

Esters: For example, ethyl cellosolve acetate, butyl cellosolve acetate, γ-butyrolactone and the like.

Nitrogen-containing heterocyclic compounds: for example, N-methylpyrrolidone, 1,3-dimethyl-2-imidazolidinone and the like.

Amides: For example, formamide, N-methylformamide, N, N-dimethylformamide and the like.

Amines: For example, monoethanolamine, diethanolamine, triethanolamine, tripropylamine, tributylamine and the like.

Saturated hydrocarbons: for example, heptane, octane, nonane, decane, undecane, dodecane, tridecane, tetradecane, pentadecane, hexadecane and the like.

Ketones: For example, acetone, methyl ethyl ketone, diethyl ketone, methyl propyl ketone, methyl isobutyl ketone, methyl amyl ketone, cyclohexanone, isophorone.

Aromatic hydrocarbons: for example, benzene, toluene, xylene, etc.

The dispersion liquid of the present invention may contain a dispersant, if necessary. Examples of the dispersant include nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, various coupling agents such as Si, Ti, Zr, and Al, and chelating agents. Be done.

Examples of the nonionic surfactant include polyhydric alcohol fatty acid ester, propylene glycol fatty acid ester, glycerin fatty acid ester, polyglycerin fatty acid ester, polyoxyethylene glycerin fatty acid ester, polyoxyethylene alkyl ether, and polyoxyethylene polyoxypropylene. Alkyl ether, polyoxyalkylene alkyl ether, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbit fatty acid ester, polyoxyethylene hydrogenated castor oil, polyoxyethylene alkylamine, polyoxyalkylene alkylamine, alkylalkanolamide, poly Examples thereof include oxyethylene alkyl phenyl ether and the like.

Examples of the silane coupling agent include vinyl trichlorosilane, vinyl trimethoxysilane, vinyl triethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, and 3-glycid. Xypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxy Silane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, N-2 (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2 (aminoethyl) -3-aminopropyltrimethoxy Silane, N-2 (aminoethyl) -3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) ) Propylamine, N-phenyl-3-aminopropyltrimethoxysilane, N- (vinylbenzyl) -2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride, 3-ureidopropyltriethoxysilane, 3-chloropropyl Trimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, bis (triethoxysilylpropyl) tetrasulfide, 3-isocyanuppropyltriethoxysilane, tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane , Methyltriethoxysilane, dimethyltriethoxysilane, phenyltriethoxysilane, hexamethyldisilazane, hexyltrimethoxysilane, decyltrimethoxysilane and the like.

The dispersion liquid of the present invention can be used as a resin composition by mixing with, for example, a resin described later. Further, in the process of molding the resin molded product of the present invention, the dispersion liquid can be spray-coated on the resin and used.

<Resin composition>
The resin composition of the present invention contains the resin and the powder of the present invention.

The amount of the powder of the present invention contained in the resin composition of the present invention can be appropriately adjusted according to the use of the resin composition of the present invention and the like. The amount of the powder of the present invention contained in the resin composition of the present invention is preferably 0.1 to 95% by mass, more preferably 0.1 to 70% by mass, based on the total mass of the resin composition of the present invention. %, More preferably 1 to 50% by mass.

Examples of the resin contained in the resin composition of the present invention include thermosetting resins, ionizing radiation curable resins, thermoplastic resins and the like. The resin contained in the resin composition of the present invention may be one kind or two or more kinds. The resin contained in the resin composition of the present invention is preferably a curable resin such as a thermosetting resin and an ionizing radiation curable resin. The curable resin may be, for example, a so-called hybrid type in which an ionizing radiation curable resin and a thermosetting resin are used in combination, or a curable resin and a thermoplastic resin are used in combination. The resin is preferably colorless and transparent from the viewpoint of obtaining the desired L ^* and b ^* values described later, but is not limited thereto.

Examples of the thermosetting resin include acrylic resin, silicone resin, phenol resin, urea resin, diallyl phthalate resin, melamine resin, guanamine resin, unsaturated polyester resin, polyurethane resin, epoxy resin, aminoalkyd resin, and melamine-urea. Examples thereof include condensed resin, silicon resin, and polysiloxane resin.

Ionizing radiation means electromagnetic waves or charged particle beams that have energy quanta capable of polymerizing or cross-linking molecules. Usually, ultraviolet rays (UV) or electron beams (EB) are used, but in addition, X Electromagnetic waves such as rays and γ-rays, and charged particle beams such as α-rays and ion rays can also be used. As the ionizing radiation curable resin, for example, one or more of a monomer, an oligomer, a prepolymer, etc. having a polymerizable unsaturated bond, a cationically polymerizable functional group, etc. in the molecule that can be crosslinked by irradiation with ionizing radiation shall be used. It may be monofunctional, bifunctional or polyfunctional, and may be acrylate or methacrylate. For example, acrylate resins such as pentaerythritol triacrylate, dipentaerythritol hexaacrylate, dipentaerythritol pentaacrylate, urethane acrylate, polyester acrylate, and epoxy acrylate can be mentioned.

Examples of the thermoplastic resin include styrene resin, (meth) acrylic resin, vinyl acetate resin, vinyl ether resin, halogen-containing resin, alicyclic olefin resin, polycarbonate resin, polyethylene naphthalate, polyethylene terephthalate and the like. Examples thereof include polyester-based resins, polyamide-based resins, cellulose derivatives, and silicone-based resins.

If necessary, the resin composition of the present invention may contain a component involved in the curing reaction of the curable resin, for example, a photopolymerization initiator (sensitizer).

The resin composition of the present invention may contain a solvent or a dispersion medium, if necessary. As the solvent or dispersion medium, the organic solvents and water listed above are used. As the solvent or dispersion medium, one type may be used alone, or two or more types may be used in combination.

The resin composition of the present invention may contain a glass frit, if necessary. Examples of the glass frit include borosilicate glass, barium borosilicate glass, zinc borosilicate glass and the like.

The resin composition of the present invention can be used as a near-infrared absorbing composition. For example, the resin composition of the present invention is applied to the surface of a desired member (for example, a resin molded product), dried, and if necessary, the resin is cured to absorb near infrared rays on the surface of the desired member. Layers can be formed. Examples of the coating method include an inkjet method, a dispenser method, a micro dispenser method, a gravure printing method, a screen printing method, a dip coating method, a spin coating method, a spray coating method, a bar coating method, a roll coating method, a calendar method and the like. Be done. In addition, the resin composition of the present invention can be used as a material for producing a near-infrared absorbing member. For example, a near-infrared absorbing member can be manufactured by molding the resin composition of the present invention according to a conventional method.

<Near infrared absorbing layer>
The near-infrared absorbing layer of the present invention contains a matrix resin and the powder of the present invention dispersed in the matrix resin.

The near-infrared absorbing layer of the present invention may be in the form of a layer formed on the surface of the support or in the form of a layer independent of the support (for example, a film, a sheet, etc.). ..

The thickness of the near-infrared absorbing layer of the present invention is not particularly limited, and can be appropriately adjusted according to the required near-infrared absorbing property and the like. The thickness of the near-infrared absorbing layer of the present invention is usually 1 to 1000 μm, preferably 1 to 100 μm, and more preferably 2 to 100 μm. When the thickness of the near-infrared absorbing layer is not uniform, it is preferable that the thickness at any five points is measured and the average value of the thicknesses at the five points is within the above range.

In one embodiment, the near-infrared absorbing layer of the present invention is a dried or cured product of the resin composition of the present invention. In this embodiment, the matrix resin is, for example, a dried product or a cured product of a resin such as a thermosetting resin, an ionizing radiation curable resin, or a thermoplastic resin, and preferably a thermosetting resin or an ionizing radiation curable resin. It is a cured product of a curable resin such as. The dried or cured resin is preferably colorless and transparent from the viewpoint of obtaining the desired L ^* and b ^* values described later, but is not limited thereto.

<Near infrared absorbing member>
The form of the near-infrared absorbing member of the present invention is not particularly limited as long as it contains the powder of the present invention.

In one embodiment, the near-infrared absorbing member of the present invention comprises a support and a near-infrared absorbing layer of the present invention formed on the surface of the support. When the shape of the support is plate-like, the near-infrared absorbing layer of the present invention can be provided on one or both surfaces of the support. In addition to the flat plate shape, the plate shape includes a three-dimensional shape having a curved portion, a bent portion, and the like. The near-infrared absorbing member according to this embodiment can be produced by applying the dispersion liquid or the resin composition of the present invention on the surface of the support, drying the member, and curing the resin if necessary. The near-infrared absorbing layer forms at least a part of the surface of the near-infrared absorbing member.

In another embodiment, the near-infrared absorbing member of the present invention includes a resin molded product and the powder of the present invention contained in the resin molded product. In the near-infrared absorbing member according to this embodiment, the powder of the present invention is kneaded into, for example, a resin molded product. The near-infrared absorbing member according to this embodiment can be produced by forming the resin composition of the present invention into a resin molded product by, for example, an inflation method, a T-die method, a calendar method, or the like.

The resin constituting the support or the resin molded product can be appropriately selected depending on the use of the near-infrared absorbing member and the like. The resin is preferably colorless and transparent from the viewpoint of obtaining the desired L ^* and b ^* values described later, but is not limited thereto. Examples of the resin include the same resins as the thermoplastic resins and thermosetting resins listed above. The resin may be one kind or two or more kinds. When molding the resin, if the molding resin is a thermoplastic resin, a resin that has been made into a fluid state by heating and melting is used, and if the molding resin is a thermosetting resin, an uncured liquid composition is used. The product is used at room temperature or heated appropriately. The heating temperature of the molding resin depends on the type of resin, but is generally about 180 to 320 ° C.

When the shape of the near-infrared absorbing member is plate-shaped, the thickness of the near-infrared absorbing member is preferably 20 μm or more, and more preferably 50 μm or more from the viewpoint of handleability and durability. On the other hand, considering the weight and the like, it is realistic to make it 10 mm or less. In addition to the flat plate shape, the plate shape includes a three-dimensional shape having a curved portion, a bent portion, and the like.

Hereinafter, the characteristics of the near-infrared absorbing member of the present invention (L ^* a ^* b ^* color system L ^* value and b ^* value, haze value, total light transmittance, light transmittance at a wavelength of 700 nm (T _λ700 )) , The transmittance of light having a wavelength of 1400 nm (T _λ1400 ), the ratio (T _λ1400 / T _λ700 ), etc.) will be described. The near-infrared absorbing member of the present invention can have two or more of the properties described herein.

When the L ^* a ^* b ^* color system L ^* value and b ^* value of the near-infrared absorbing member are measured, the L ^* value is preferably 85 or more and 97 or less, more preferably 85 or more and 95 or less, and further. It is preferably 85 or more and 93 or less, and the b ^* value is preferably -2 or more and 7 or less, more preferably -1 or more and 5 or less, and even more preferably -0.5 or more and 4.5 or less. Since the particles and powders of the present invention have a reduced bluish tint, such L ^* and b ^* values can be realized.

The L ^* a ^* b ^* color-based L ^* value and b ^* value of the near-infrared absorbing member are the type and content of the resin constituting the support or resin molded body, and the matrix resin in the near-infrared absorbing layer. By adjusting the content, crystal structure, average particle size, BET specific surface area, etc. of the powder of the present invention, such as the type and content of the above, it can be adjusted to a desired range.

A preferred embodiment of the method for measuring the L ^* a ^* b ^* color system L ^* value and the b ^* value of the near-infrared absorbing member is as follows. In an embodiment in which the near-infrared absorbing member includes a support and a near-infrared absorbing layer formed on the surface of the support, a color difference meter (for example, CM-2600d manufactured by Konica Minolta) is used. , The surface of the near-infrared absorbing layer in the near-infrared absorbing member is irradiated with a pulse xenon lamp at an incident angle of 0 degrees (the normal direction of the surface of the near-infrared absorbing layer is 0 degrees), and based on the SCI method. , L ^* value and b ^* value are measured. On the other hand, in the embodiment in which the near-infrared absorbing member contains the resin molded body and the powder of the present invention contained in the resin molded body, the angle of incidence on the surface of the resin molded body is 0 in the same manner as described above. The pulse xenon lamp is irradiated at a degree (the normal direction of the surface of the resin molded product is 0 degree), and the L ^* value and the b ^* value are measured. In any of the embodiments, the L ^* value and the b ^* value are measured at any 10 points, and the average value of the L ^* values at the 10 points and the average value of the b ^* values at the 10 points are set to have near-infrared ray absorption, respectively. Let it be the L ^* value and b ^* value of the member.

The haze value of the near-infrared absorbing member of the present invention is particularly related to the average particle size of the powder of the present invention contained in the near-infrared absorbing layer or the resin molded body of the present invention. When the near-infrared absorbing member of the present invention is required to be transparent, the haze value is preferably 10% or less, more preferably 8% or less, and even more preferably 5% or less.

The haze value of the near-infrared absorbing member of the present invention is desired by adjusting the type and content of the matrix resin, the content of the powder of the present invention, the crystal structure, the average particle size, the BET specific surface area, and the like. It can be adjusted to a range.

The total light transmittance of the near-infrared absorbing member of the present invention is particularly related to the average particle size of the powder of the present invention contained in the near-infrared absorbing layer or the resin molded body of the present invention. When transparency is required for the near-infrared absorbing member of the present invention, the total light transmittance is preferably 60% or more and less than 92%, more preferably 60% or more and 85% or less, and even more preferably 60% or more and 75% or less. Is.

The transmittance (T _λ700 ) of light having a wavelength of 700 nm in the near-infrared absorbing member of the present invention is an index of the transmittance of red visible light. Improving the transparency of visible light contributes to the reduction of bluish tint. Therefore, the transmittance of light having a wavelength of 700 nm is preferably large, specifically 40% or more, more preferably 45% or more, and even more preferably 50% or more. The upper limit of the transmittance of light having a wavelength of 700 nm is not particularly limited, but is preferably 80%, more preferably 70%.

On the other hand, the transmittance of light having a wavelength of 1400 nm (T _{λ 1400} ) is an index of the absorbency (blocking property) of near infrared rays. Therefore, the transmittance of light having a wavelength of 1400 nm is preferably small, specifically 50% or less, more preferably 35% or less, and even more preferably 25% or less.

The ratio (T _λ1400 / T _λ700 ) in the near-infrared absorbing member of the present invention is an index of the balance between the transmission of red visible light and the absorption (blocking property) of near-infrared rays. The bluish tint can be reduced by realizing the absorption (blocking property) of near infrared rays while maintaining the transmission of visible red light. That is, a decrease in the ratio (T _λ1400 / T _λ700 ) is an index for reducing the bluish _tint . That is, the ratio (T _λ1400 / T _λ700 ) is preferably 0.50 or less, more preferably 0.4 or less, and even more preferably 0.25 or less. The lower limit of the ratio (T _λ1400 / T _λ700 ) is not particularly limited, but is preferably 0.01, more preferably 0.03.

The total light transmittance, the light transmittance at a wavelength of 700 nm, and the light transmittance at a wavelength of 1400 nm of the near-infrared absorbing member of the present invention described above are the content of the powder of the present invention, such as the type and content of the matrix resin. , The crystal structure, the average wavelength, the BET specific surface area, and the like can be adjusted to a desired range.

Haze measurements are performed in accordance with JIS K 7136: 2000. Measurements of total light transmittance are performed in accordance with JIS K 7375: 2008. For the measurement of haze and total light transmittance, for example, a haze meter (“NDH2000” manufactured by Nippon Denshoku Industries Co., Ltd.) is used.

As described above, the near-infrared absorbing material of the present invention (near-infrared absorbing particles, powder composed of the near-infrared absorbing particles, dispersion liquid containing the powder, resin composition containing the powder, etc. ) And the near-infrared absorbing layer and the near-infrared absorbing member obtained by using the near-infrared absorbing material, it can be suitably used as a window material, an electronic device, etc. that are required to have near-infrared absorbing property. ..

[Example 1]
(1) Preparation of near-infrared absorbing particles Tungstic acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) so that the molar ratio is Cs: Nb: W = 0.25: 0.1: 0.9 and the total amount is 4 g. ), Cesium carbonate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) and niobium pentoxide (manufactured by Mitsui Mining & Smelting Co., Ltd.), and mixed in a dairy pot. % Using a tubular furnace of _H 2 -Ar gas atmosphere, and then calcined 3 hours at 550 ° C.. Then, 0.1 wt% of carbon powder was added to the obtained powder amount, mixed in a mortar, and then calcined at 800 ° C. for 3 hours using a tubular furnace having an Ar gas atmosphere. As a result, a powder having a composition formula represented by Cs _0.25 Nb _0.1 W _0.9 O ₃ was obtained.

(2) Preparation of Dispersion Solution A mixture containing 27% by weight of the powder obtained in (1) above, 65% by weight of 2-butanone, and 8% by weight of the dispersant was prepared, and a paint shaker was used for this mixture. Was used for 20 hours of dispersion treatment to prepare a dispersion.

(3) Formation of near-infrared absorbing layer and near-infrared absorbing member 8% by weight of the dispersion obtained in (2) above, 12% by weight of the thermosetting resin (Acridic A-165 manufactured by DIC), 2 -A paint containing 80% by weight of butanone is prepared, and this paint is applied on a polyethylene terephthalate (PET) film (thickness 100 μm) with a bar coater to form a coating film (thickness 3 μm), and dried at 80 ° C. for 10 minutes. The solvent was evaporated to form a resin layer (near-infrared absorbing layer) on the PET film to form a near-infrared absorbing member.

(4) Analysis and measurement of powder physical properties In order to clarify the physical properties of the powder obtained in (1) above, the BET specific surface area and the average grain size by dynamic light scattering method (DLS) are obtained in the same manner as above. Analysis or measurement of diameter, average particle size and crystal structure by small-angle X-ray scattering (SAXS) was performed. Further, in the same manner as described above, the L ^* value, b ^* value, haze value (Hz), total light transmittance (TT), and light transmittance at a wavelength of 700 nm of the near-infrared absorbing member using the powder ( _T λ700) and transmittance of light having a wavelength of 1400nm the analysis or measurement of the _(T λ1400) was performed.
The results are shown in Table 1.

[Example 2]
Cs _0.25 Nb _0.2 W _0.8 O ₃ in the same manner as in Example 1 except that the molar ratio was changed to Cs: Nb: W = 0.25: 0.2: 0.8. A powder having the composition formula shown was obtained. The analysis and measurement of the obtained powder were carried out in the same manner as in Example 1.

[Example 3]
Cs _0.25 Nb _0.3 W _0.7 O ₃ in the same manner as in Example 1 except that the molar ratio was changed to Cs: Nb: W = 0.25: 0.3: 0.7. A powder having the composition formula shown was obtained. The analysis and measurement of the obtained powder were carried out in the same manner as in Example 1.

[Example 4]
Cs _0.25 Nb _0.4 W _0.6 O ₃ in the same manner as in Example 1 except that the molar ratio was changed to Cs: Nb: W = 0.25: 0.4: 0.6. A powder having the composition formula shown was obtained. The analysis and measurement of the obtained powder were carried out in the same manner as in Example 1.

[Example 5]
Implemented except that the raw material used was changed from niobium pentoxide to aluminum oxide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) and the molar ratio was changed to Cs: Al: W = 0.25: 0.1: 0.9. In the same manner as in Example 1, a powder having a composition formula represented by Cs _0.25 Al _0.1 W _0.9 O ₃ was obtained. The analysis and measurement of the obtained powder were carried out in the same manner as in Example 1.

[Example 6]
Cs _0.25 Al _0.2 W _0.8 O ₃ in the same manner as in Example 5 except that the molar ratio was changed to Cs: Al: W = 0.25: 0.2: 0.8. A powder having the composition formula shown was obtained. The analysis and measurement of the obtained powder were carried out in the same manner as in Example 1.

[Example 7]
Cs _0.25 Al _0.3 W _0.7 O ₃ in the same manner as in Example 5 except that the molar ratio was changed to Cs: Al: W = 0.25: 0.3: 0.7. A powder having the composition formula shown was obtained. The analysis and measurement of the obtained powder were carried out in the same manner as in Example 1.

[Example 8]
Cs _0.25 Al _0.4 W _0.6 O ₃ in the same manner as in Example 5 except that the molar ratio was changed to Cs: Al: W = 0.25: 0.4: 0.6. A powder having the composition formula shown was obtained. The analysis and measurement of the obtained powder were carried out in the same manner as in Example 1.

[Example 9]
Implementation except that the molar ratio was changed to Cs: Al: W = 0.25: 0.1: 0.9 and the wet pulverization conditions were changed (the pulverization time was changed to 5 hours). In the same manner as in Example 5, a powder having a composition formula represented by Cs _0.25 Al _0.1 W _0.9 O ₃ was obtained. The analysis and measurement of the obtained powder were carried out in the same manner as in Example 1.

[Example 10]
Conducted except that the raw material used was changed from niobium pentoxide to scandium oxide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) and the molar ratio was changed to Cs: Sc: W = 0.25: 0.1: 0.9. In the same manner as in Example 1, a powder having a composition formula represented by Cs _0.25 Sc _0.1 W _0.9 O ₃ was obtained. The analysis and measurement of the obtained powder were carried out in the same manner as in Example 1.

[Comparative Example 1]
Tungsic acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), rubidium carbonate (Fujifilm Wako Pure Chemical Industries, Ltd.) so that the molar ratio is Rb: Nb: W = 0.25: 0.1: 0.9 and the total amount is 4 g. Rb _0.25 Nb _0.1 W _0.9 O ₃ in the same manner as in Example 1 except that niobium pentoxide (manufactured by Mitsui Metal Mining Co., Ltd.) was blended. Obtained powder to have. The analysis and measurement of the obtained powder were carried out in the same manner as in Example 1.

[Comparative Example 2]
Tungstic acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), sodium carbonate (Fujifilm Wako Pure Chemical Industries, Ltd.) so that the molar ratio is Na: Nb: W = 0.25: 0.1: 0.9 and the total amount is 4 g. The composition formula represented by Na _0.25 Nb _0.1 W _0.9 O ₃ was obtained in the same manner as in Example 1 except that niobium pentoxide (manufactured by Mitsui Mining & Smelting Co., Ltd.) was blended. Obtained powder to have. The analysis and measurement of the obtained powder were carried out in the same manner as in Example 1.

[Comparative Example 3]
Tungsic acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), potassium carbonate (Fujifilm Wako Pure Chemical Industries, Ltd.) so that the molar ratio is K: Nb: W = 0.25: 0.1: 0.9 and the total amount is 4 g. The composition formula represented by K _0.25 Nb _0.1 W _0.9 O ₃ was obtained in the same manner as in Example 1 except that niobium pentoxide (manufactured by Mitsui Mining & Smelting Co., Ltd.) was blended. Obtained powder to have. The analysis and measurement of the obtained powder were carried out in the same manner as in Example 1.

[Comparative Example 4]
Cs _0.25 Nb _0.5 W _0.5 O ₃ in the same manner as in Example 1 except that the molar ratio was changed to Cs: Nb: W = 0.25: 0.5: 0.5. A powder having the composition formula shown was obtained. The analysis and measurement of the obtained powder were carried out in the same manner as in Example 1.

[Comparative Example 5]
Cs _0.25 Al _0.5 W _0.5 O ₃ in the same manner as in Example 5 except that the molar ratio was changed to Cs: Al: W = 0.25: 0.5: 0.5. A powder having the composition formula shown was obtained. The analysis and measurement of the obtained powder were carried out in the same manner as in Example 1.

The results of Examples 1 to 10 and Comparative Examples 1 to 5 are shown in Table 1.

As shown in Table 1, since the powders of Examples 1 to 10 have the composition represented by the formula (I) of the present invention, they are transparent as compared with the powders of Comparative Examples 1 to 5 having no such composition. It can be seen that the bluish tint is reduced while maintaining the sex.

The powder of Example 9 has an average particle size of more than 150 nm and a BET specific surface area of less than 10 m ² / g measured by a dynamic light scattering method, and has a large particle size, so that a uniform resin layer can be formed. There wasn't. Therefore, for the powder of Example 9, the haze value and the total light transmittance were not measured.

Claims (16)

The following formula (I):
Cs _p M _q W _{1-q Or} ... (I)
[During the ceremony,
M represents one or more elements selected from the group consisting of Nb, Ta, Al and Sc.
p satisfies 0.01 ≦ p <0.3 and
q satisfies 0.01 ≦ q <0.5 and
q and r satisfy 3 <r / (1-q). ]
Near-infrared absorbing particles having a composition represented by. The near-infrared absorbing particle according to claim 1, which has a hexagonal crystal structure. A powder composed of the near-infrared absorbing particles according to claim 1 or 2. The powder according to claim 3, wherein the average particle size measured by a dynamic light scattering method is 150 nm or less. The powder according to claim 3 or 4, wherein the average particle size measured by the small-angle X-ray scattering method is 200 nm or less. The powder according to any one of claims 3 to 5, which has a BET specific surface area of 10 m ² / g or more. A dispersion liquid containing a dispersion medium and the powder according to any one of claims 3 to 6 dispersed in the dispersion medium. A resin composition containing a resin and the powder according to any one of claims 3 to 6. A near-infrared absorbing layer containing the matrix resin and the powder according to any one of claims 3 to 6 dispersed in the matrix resin. A near-infrared absorbing member comprising a support and a near-infrared absorbing layer formed on the surface of the support according to claim 9. A near-infrared absorbing member containing a resin molded body and the powder according to any one of claims 3 to 6 contained in the resin molded body. The near-infrared absorbing member according to claim 10 or 11, wherein the L ^* value and b ^* value of the L ^* a ^* b ^* color system are 85 or more and 97 or less and -2 or more and 7 or less, respectively. The near-infrared absorbing member according to any one of claims 10 to 12, wherein the haze value is 10% or less. The near-infrared absorbing member according to any one of claims 10 to 13, wherein the total light transmittance is 60% or more and less than 92%. The near-infrared absorbing member according to any one of claims 10 to 14, wherein the transmittance of light having a wavelength of 700 nm is 40% or more. For the transmittance of light having a wavelength of _700nm (T λ700), the ratio of the transmittance of light having a wavelength of _{1400nm (T λ1400) (T λ1400} / T λ700) is 0.50 or less, any one of claims 10 to 15 The near-infrared absorbing member according to item 1.