Near-infrared transmissive composition and ink

Abstract

The present invention provides a near-infrared transmissive composition that achieves both light-blocking properties in a visible light region and transmissive properties in a near-infrared region, while exhibiting excellent storage stability. The present invention relates to a near-infrared transmissive composition that contains black particles containing an organic black compound, and an additive, wherein the average transmittance in a wavelength range of 400 nm to less than 800 nm, which is measured using a spectrophotometer, is 20% or less, and the average transmittance in a wavelength range of 850 nm to less than 2500 nm is 80% or more.

Description

Near-infrared transparent composition and ink

[0001] The present invention relates to a near-infrared transparent composition and ink.

[0002] Carbon black has traditionally been used as a black material, with other materials such as iron oxide black (iron tetroxide) also being used. These materials exhibit a black color and absorb light with wavelengths ranging from the visible light region to the far-infrared region. Therefore, articles such as coatings colored with these black materials are prone to becoming hot due to the absorption of sunlight. Furthermore, because carbon black is electrically conductive, articles colored with carbon black have poor electrical insulation properties. Meanwhile, with the use of infrared laser radiation and the development of corresponding sensors in the fields of electronics and optical devices, many fields are seeking black materials with properties not found in conventional black materials such as carbon black. For example, in infrared communications, infrared camouflage, and optical filters, oil-soluble dyes have been used as coloring materials for infrared-transmitting filters. However, these oil-soluble dyes have problems with durability, such as heat resistance, solvent resistance, and light resistance. Therefore, dark-colored materials with excellent durability and infrared transmittance are needed.

[0003] In particular, black materials that have sufficient transparency to light rays having wavelengths from near-infrared to infrared have been put to practical use. For example, Patent Document 1 describes a dark azo pigment obtained by a coupling reaction between 2-hydroxy-11H-benzo[a]carbazole-3-carboxy-N-benzimidazolone-5-amide as a coupling component and a known diazo compound as a diazo component. Furthermore, Patent Document 2 describes a black azo pigment having a volume fraction of 2% to 30% by volume, an average dispersed particle diameter in a film of 1 nm to 200 nm, an optical density per μm thickness of 1 or more, and a volume resistivity of 10 １１ Patent Document 3 describes a composition for a color filter containing a near-infrared-transmitting black coloring material, and describes a bisbenzofuranone-based pigment as the near-infrared-transmitting black coloring material.

[0004] International Publication No. 2010 / 044393 International Publication No. 2012 / 026577 Japanese Patent Application Laid-Open No. 2014-130173

[0005] In recent years, near-infrared sensors and near-infrared cameras have been used in various information terminals, such as smartphones and tablet PCs, to enhance security. Near-infrared sensors and near-infrared cameras, such as motion sensors, are also used in automobiles. Optical filters for these applications require high near-infrared transmittance and visible light blocking properties. However, even the materials disclosed in Patent Documents 1 and 2 still have insufficient near-infrared transmittance. Furthermore, there is also the problem of high visible light transmittance, which may restrict the design of the coating film, such as by increasing the thickness of the coating film or adding a large amount of black material to block visible light. Furthermore, optical filters formed from the color filter composition disclosed in Patent Document 3 also have problems such as high transmittance, particularly near the upper limit of the visible light range, and insufficient scattering suppression in the near-infrared range. Furthermore, particularly when organic materials are used, there are problems with storage stability, such as the tendency for structural changes in the black pigment to occur when exposed to air for long periods of time or to relatively high-energy ultraviolet or visible light, resulting in reduced light blocking in the visible light range and transmittance in the near-infrared range.

[0006] In view of the above-mentioned current situation, an object of the present invention is to provide a near-infrared transmitting composition that can achieve both light-shielding properties in the visible light region and transmittance in the near-infrared region and has excellent storage stability.

[0007] The present disclosure (1) is a near-infrared transmitting composition containing black particles including an organic black compound and an additive, and having an average transmittance of 20% or less in a wavelength region of 400 nm or more and less than 800 nm, and an average transmittance of 80% or more in a wavelength region of 850 nm or more and less than 2500 nm, as measured using a spectrophotometer. The present disclosure (2) is a near-infrared transmitting composition, which is exposed to ultraviolet light with a wavelength of 300 nm or more and 400 nm or less for 300 hours in an accelerated weathering deterioration test using a super xenon weather meter, and has a transmittance of T before and after exposure at a wavelength λ nm, as measured using a spectrophotometer. λ and T λ（３００ｈ）The near-infrared transparent composition of the present disclosure (1) satisfies the following formulas (a) to (d): (a): |T ６５０（３００ｈ） -T ６５０ |<30 (b): |T ９０５（３００ｈ） -T ９０５ |<15 (c): |T ９４０（３００ｈ） -T ９４０ |<15 (d): |T １５５０（３００ｈ） -T １５５０ |<15 This disclosure (3) is a spectrophotometer that measures the diffuse transmittance T in the wavelength range of 850 nm or more and less than 2500 nm. ｄ The present disclosure (4) is a near-infrared transmitting composition according to the present disclosure (1) or (2), in which, when exposed to ultraviolet light with a wavelength of 300 nm or more and 400 nm or less for 300 hours in an accelerated weathering deterioration test using a super xenon weather meter, the diffuse transmittance T ｄ（３００ｈ）The near-infrared transparent composition of the present disclosure (1), (2), or (3), wherein the maximum value of (a) is 10% or less. The present disclosure (5) is the near-infrared transparent composition of the present disclosure (1), (2), (3), or (4), wherein the additive is at least one selected from the group consisting of a radical scavenger and an ultraviolet absorber. The present disclosure (6) is the near-infrared transparent composition of the present disclosure (5), wherein the radical scavenger is at least one selected from the group consisting of a hindered phenol-based compound, a hindered amine-based compound, a nitroxyl-containing polymerization inhibitor, and a sulfur-containing heterocyclic compound. The present disclosure (7) is the near-infrared transparent composition of the present disclosure (5) or (6), wherein the ultraviolet absorber is at least one selected from the group consisting of a benzotriazole-based compound, a triazine-based compound, and a benzophenone-based compound. The present disclosure (8) is the near-infrared transparent composition of the present disclosure (1), (2), (3), (4), (5), (6), or (7), wherein the organic black compound has a structural unit derived from a compound having an aromatic ring containing a hydroxy group and a structural unit derived from a compound having a benzene ring containing an amino group. The present disclosure (9) is the near-infrared transparent composition of the present disclosure (1), (2), (3), (4), (5), (6), (7), or (8), wherein the organic black compound has a crosslinking agent or a structural unit derived from the crosslinking agent. The present disclosure (10) is the near-infrared transparent composition of the present disclosure (1), (2), (3), (4), (5), (6), (7), or (8), wherein the organic black compound includes an auxochrome. The present disclosure (11) is an ink comprising the near-infrared transparent composition of the present disclosure (1), (2), (3), (4), (5), (6), (7), (8), (9), or (10), a solvent, and a binder resin. The present invention will be described in detail below.

[0008] As a result of extensive research, the present inventors have found that a high-performance optical film can be produced by preparing a near-infrared transparent composition containing black particles including an organic black compound and an additive, the near-infrared transparent composition having a predetermined average transmittance in a wavelength range of 400 nm or more and less than 800 nm and an average transmittance in a wavelength range of 850 nm or more and less than 2500 nm, as measured using a spectrophotometer. The present inventors have also found that preparing such a composition can suppress structural changes in the black particles and improve storage stability even when exposed to air or ultraviolet or visible light for a long period of time. Furthermore, the present inventors have found that such an optical film can achieve both light-blocking properties in the visible light range and transmittance in the near-infrared range, and can be particularly suitable for use in optical sensors such as near-infrared sensors for smartphones, automobiles, and near-infrared cameras, and have completed the present invention.

[0009] The near-infrared transparent composition contains black particles. By containing the black particles, the composition can have excellent blackness and high light-blocking properties in the visible light region.

[0010] The black particles contain an organic black compound. By containing the organic black compound, particles can be made finer and more uniform than conventional particles, making it possible to produce a coating film with a higher degree of blackness. The organic black compound preferably contains a structural unit derived from a compound having an aromatic ring containing a hydroxy group and a structural unit derived from a compound having a benzene ring containing an amino group. By containing the organic black compound, black particles can be obtained that have high transmittance, particularly in the near-infrared region, and low transmittance in the visible light region.

[0011] Examples of the aromatic ring include a benzene ring, a naphthalene ring, an anthracene ring, and the like. Of these, a benzene ring and a naphthalene ring are preferred. Examples of compounds having a naphthalene ring containing a hydroxy group include 1-naphthol, 2-naphthol, dihydroxynaphthalene, trihydroxynaphthalene, tetrahydroxynaphthalene, and pentahydroxynaphthalene. Of these, dihydroxynaphthalene and 1-naphthol are preferred, and among dihydroxynaphthalenes, 1,3-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, and 1,6-dihydroxynaphthalene are preferred. Furthermore, examples of compounds having a benzene ring containing a hydroxy group include phenol and derivatives thereof, catechol, resorcinol, hydroquinone and derivatives thereof, hydroxyquinol, phloroglucinol, pyrogallol and derivatives thereof, and tetrahydroxybenzene and derivatives thereof.

[0012] The compound having an aromatic ring containing a hydroxyl group may be used in combination with a plurality of types. In this case, it is preferable to use a combination of compounds having aromatic rings containing different hydroxyl groups, and it is more preferable to use a combination of a compound having a naphthalene ring containing a hydroxyl group and a compound having a benzene ring containing a hydroxyl group. This makes it possible to exhibit the properties of visible light blocking by the naphthalene ring and near-infrared light transmission by the benzene ring, which are difficult to coexist. Furthermore, it is also possible to use a combination of a plurality of types of compounds having a naphthalene ring containing a hydroxyl group.

[0013] Furthermore, the compound having a benzene ring containing a hydroxy group preferably has 1 to 3 hydroxy groups, and the compound having a naphthalene ring containing a hydroxy group preferably has 1 to 4 hydroxy groups, which makes it possible to maintain general nucleophilicity.

[0014] The content of the structural unit derived from the compound having an aromatic ring containing a hydroxy group in the organic black compound is preferably 10% by weight or more, more preferably 15% by weight or more, even more preferably 20% by weight or more, even more preferably 25% by weight or more, and is preferably 90% by weight or less, more preferably 85% by weight or less, even more preferably 80% by weight or less, and even more preferably 75% by weight or less.

[0015] The compound having a benzene ring containing an amino group serves as an auxochrome that donates electrons to a compound having an aromatic ring containing a hydroxy group as a chromophore. Therefore, the compound having a benzene ring containing an amino group may have an ether group, a hydroxy group, or the like in addition to an amino group. Furthermore, the compound having a benzene ring containing an amino group is one that contains an amino group, and examples thereof include those containing a primary amino group, a secondary amino group, and a tertiary amino group, but those containing a primary amino group are preferred.

[0016] Examples of compounds having a benzene ring containing an amino group include aromatic monoamines and aromatic polyamines. Examples of aromatic monoamines include aniline, p-toluidine, p-ethylaniline, p-anisidine, p-butylaniline, p-phenetidine, and 4-aminophenol. Among these, aniline and p-anisidine are preferred. Examples of aromatic polyamines include N,N-dimethyl-1,4-phenylenediamine, N,N-diethyl-1,4-phenylenediamine, 1,4-phenylenediamine, tolylenediamine, and 4,4'-diaminodiphenylmethane. In particular, in the aromatic polyamines, the first amino group is preferably an unsubstituted primary amino group, and those having an electron-donating alkyl group, amino group, or alkoxy group at the ortho- or para-position of the amino group, more preferably the para-position, are preferred. Regarding the second or subsequent amino group or alkoxy group substituted at the para-position, those substituted with an alkyl group and free of active hydrogen are preferred. Specifically, those having the structure of the following formula (1) are preferred:

[0017]

[0018] In formula (1), RＸ and R ｙ each independently represents hydrogen, —OR, or —NR′R″, R represents an alkyl group having 20 or less carbon atoms, and R′ and R″ each independently represent a hydrogen atom or an alkyl group having 20 or less carbon atoms.

[0019] The compound having a benzene ring containing an amino group preferably has 1 to 3 amino groups. This makes the compound having an aromatic ring containing an amino group more electron-rich, allowing for sufficient reaction. Furthermore, by limiting the number of amino groups to 3 or less, the basicity of each amino group can be made appropriate. Furthermore, the amino group is preferably present at the end of the molecule, from the viewpoint of being less susceptible to a decrease in kinetic reactivity due to steric hindrance.

[0020] The content of the structural unit derived from the compound having a benzene ring containing an amino group in the organic black compound is preferably 10% by weight or more, more preferably 15% by weight or more, even more preferably 20% by weight or more, even more preferably 30% by weight or more, and is preferably 60% by weight or less, more preferably 50% by weight or less, even more preferably 45% by weight or less, and even more preferably 40% by weight or less.

[0021] The organic black compound may have a structural unit derived from a compound containing an amino group other than the compound having a benzene ring containing an amino group, such as ammonia, a chain aliphatic amine, an alicyclic amine, or an alkanolamine.

[0022] Examples of the chain aliphatic amine include ethylamine, 1-propylamine, 2-propylamine, 1-butylamine, 1-pentylamine, 1-hexylamine, 1-heptylamine, 1-octylamine, 1-laurylamine, 1,2-ethanediamine, 1,3-propanediamine, 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, ethylenetriamine, diethylenetriamine, ethylhydrazine, 1-propylhydrazine, 1-butylhydrazine, 1-pentylhydrazine, 1-hexylhydrazine, 1-heptylhydrazine, 1-octylhydrazine, succinic acid dihydrazide, terephthalic acid dihydrazide, guanidine, 1-butylguanidine, 1-cyanoguanidine, and dicyandiamide.

[0023] Examples of the alicyclic amine include cyclopropylamine, cyclobutylamine, cyclopentylamine, cyclohexylamine, cyclopropanediamine, isophoronediamine, cyclobutanediamine, cyclopentanediamine, cyclohexanediamine, bis(4-aminocyclohexyl)methane, piperazine, N-aminoethylpiperazine, etc. Examples of the alkanolamine include monoethanolamine, diethanolamine, triethanolamine, etc.

[0024] The organic black compound having a structural unit derived from a compound having an aromatic ring containing a hydroxy group and a structural unit derived from a compound having a benzene ring containing an amino group preferably contains an auxochrome. Examples of the auxochrome include the amino group described above, as well as a thiol group, an aldehyde group, a carboxy group, and a hydroxy group. The auxochrome may be of one type or two or more types.

[0025] The black particles are preferably formed by oxidizing an organic black compound with an oxidizing agent. By adopting this configuration, the black particles can have extremely high light-blocking properties in the visible light region and extremely high transmittance in the near-infrared region.

[0026] Examples of the oxidizing agent include ketone compounds, peroxides, organic acids, persulfates, nitrates, amine oxide compounds, salts of halogen oxoacids, and hydrazine. Examples of the ketone compounds include quinone compounds such as benzoquinone, 1,2-naphthoquinone, anthraquinone, and chloranil. Examples of the peroxides include hydrogen peroxide and t-butyl hydroperoxide. Examples of the organic acids include formic acid, acetic acid, and propionic acid. Examples of the persulfates include sodium persulfate, potassium persulfate, and ammonium persulfate. Examples of the nitrates include sodium nitrate, ammonium nitrate, and cerium ammonium nitrate. Examples of the amine oxide compounds include N-methylmorpholine N-oxide. Examples of the salts of halogen oxoacids include sodium hypochlorite and sodium chlorite. The oxidizing agents may be used alone or in combination of two or more. Among these, ketone compounds, peroxides, organic acids, persulfates, and hydrazine are preferred. It is more preferable to use a ketone compound and a peroxide in combination. Note that the oxidizing agent is different from the compound having an aromatic ring containing a hydroxy group, the compound having an aromatic ring containing an amino group, and other compounds containing an amino group.

[0027] When the black particles contain an organic black compound oxidized with an oxidizing agent, the weight ratio of the oxidizing agent used to the structural units derived from the compound having an aromatic ring containing a hydroxy group (oxidizing agent / structural units derived from the compound having an aromatic ring containing a hydroxy group) is preferably 0.1 or more, more preferably 0.2 or more, even more preferably 0.3 or more, even more preferably 0.5 or more, preferably 5 or less, more preferably 3 or less, even more preferably 2 or less, and even more preferably 1 or less. Note that this weight ratio can be calculated based on the amount of each component added. Furthermore, it is preferable that the black particles contain an organic black compound oxidized with an oxidizing agent, but do not contain the oxidizing agent.

[0028] When the black particles contain an organic black compound oxidized by an oxidizing agent, the weight ratio of the oxidizing agent used to the structural units derived from the compound having a benzene ring containing an amino group (oxidizing agent / structural units derived from the compound having an aromatic ring containing an amino group) is preferably 0.1 or more, more preferably 0.5 or more, even more preferably 1 or more, even more preferably 1.5 or more, preferably 10 or less, more preferably 8 or less, even more preferably 6 or less, and even more preferably 3 or less. The weight ratio can be calculated based on the amount of each component added. Furthermore, it is preferable that the black particles contain an organic black compound oxidized by an oxidizing agent, but do not contain the oxidizing agent.

[0029] The organic black compound preferably has a structural unit obtained by oxidizing a compound having an aromatic ring containing a hydroxy group or a compound having a benzene ring containing an amino group. By having the above-mentioned structure, it is possible to further improve the light-shielding property in the visible light region and to further improve the transmittance in the near-infrared region. In addition, the organic black compound having a structural unit obtained by oxidizing a compound having an aromatic ring containing a hydroxy group or a compound having a benzene ring containing an amino group is １ H and １３ This can be confirmed by various NMR measurements such as C.

[0030] The black particles preferably contain a crosslinking agent or a structural unit derived from a crosslinking agent. By having the above-described structure, the organic black compound having the structural unit derived from the compound having an aromatic ring containing a hydroxy group and the structural unit derived from the compound having a benzene ring containing an amino group is crosslinked, resulting in black particles with excellent handleability, in which the structural components are resinified. In this case, the organic black compound has a structure having the structural unit derived from the compound having an aromatic ring containing a hydroxy group, the structural unit derived from the compound having a benzene ring containing an amino group, and the structural unit derived from the crosslinking agent. Note that the crosslinking agent is different from the compound having an aromatic ring containing a hydroxy group, the compound having a benzene ring containing an amino group, and other compounds containing amino groups.

[0031] The crosslinking agent is preferably an electrophilic reactant that is susceptible to nucleophilic attack. Examples of the crosslinking agent include polyamine-based crosslinking agents, thiourea-based crosslinking agents, thiadiazole-based crosslinking agents, triazine-based crosslinking agents, quinoxaline-based crosslinking agents, bisphenol-based crosslinking agents, organic peroxide-based crosslinking agents, aldehyde-based crosslinking agents, and silane-based crosslinking agents. Phenol-based crosslinking agents such as resol phenolic resins can also be used.

[0032] Examples of the polyamine-based crosslinking agents include ethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, hexamethylenetetramine, p-phenylenediamine, cumenediamine, N,N'-dicinnamylidene-1,6-hexanediamine, ethylenediamine carbamate, and hexamethylenediamine carbamate. Examples of the thiourea-based crosslinking agents include 2-mercaptoimidazoline (ethylenethiourea), 1,3-diethylthiourea, 1,3-dibutylthiourea, and trimethylthiourea. Examples of the thiadiazole-based crosslinking agents include 2,5-dimercapto-1,3,4-thiadiazole and 2-mercapto-1,3,4-thiadiazole-5-thiobenzoate. Examples of the triazine crosslinking agents include 2,4,6-trimercapto-1,3,5-triazine, 2-hexylamino-4,6-dimercaptotriazine, 2-diethylamino-4,6-dimercaptotriazine, 2-cyclohexylamino-4,6-dimercaptotriazine, 2-dibutylamino-4,6-dimercaptotriazine, 2-anilino-4,6-dimercaptotriazine, and 2-phenylamino-4,6-dimercaptotriazine. Examples of the quinoxaline crosslinking agents include 2,3-dimercaptoquinoxaline, quinoxaline-2,3-dithiocarbonate, 6-methylquinoxaline-2,3-dithiocarbonate, and 5,8-dimethylquinoxaline-2,3-dithiocarbonate. Examples of the bisphenol crosslinking agents include bisphenol AF and bisphenol S. Examples of the organic peroxide crosslinking agent include tert-butyl hydroperoxide, p-menthane hydroperoxide, dicumyl peroxide, tert-butyl peroxide, 1,3-bis(tert-butylperoxyisopropyl)benzene, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, benzoyl peroxide, and tert-butyl peroxybenzoate.Examples of the aldehyde crosslinking agents include glyoxal, malondialdehyde, succindialdehyde, maleic dialdehyde, glutaric dialdehyde, formaldehyde, acetaldehyde, benzaldehyde, and 1,3,5-trioxane. Examples of the silane crosslinking agents include alkoxysilanes such as methyltrimethoxysilane, dimethyldimethoxysilane, vinyltrimethoxysilane, phenyltrimethoxysilane, and methyltriethoxysilane. Of these, polyamine crosslinking agents and aldehyde crosslinking agents are preferred in terms of ease of addition (solvent solubility) and high reactivity (the carbon atom adjacent to the highly electronegative heteroatom is located in a relatively large space (less steric hindrance)).

[0033] When the black particles contain an organic black compound having structural units derived from a compound having an aromatic ring containing a hydroxy group and structural units derived from a compound having a benzene ring containing an amino group, the weight ratio of the structural units derived from the compound having a benzene ring containing an amino group to the structural units derived from the compound having an aromatic ring containing a hydroxy group (structural units derived from a compound having a benzene ring containing an amino group / structural units derived from a compound having an aromatic ring containing a hydroxy group) is preferably 0.1 or more, more preferably 0.2 or more, even more preferably 0.25 or more, preferably 10 or less, more preferably 5 or less, and even more preferably 3.5 or less. Within the above range, the light-blocking properties in the visible light region can be further improved, and the transmittance in the near-infrared region can be further improved.

[0034] When the black particles contain an organic black compound having structural units derived from a compound having an aromatic ring containing a hydroxy group and structural units derived from a crosslinking agent, the weight ratio of the structural units derived from the crosslinking agent to the structural units derived from the compound having an aromatic ring containing a hydroxy group (structural units derived from crosslinking agent / structural units derived from a compound having an aromatic ring containing a hydroxy group) is preferably 0.1 or more, more preferably 0.2 or more, and even more preferably 0.3 or more; and is preferably 10 or less, more preferably 5 or less, and even more preferably 2 or less.

[0035] When the black particles contain an organic black compound having structural units derived from a compound having a benzene ring containing an amino group, and structural units derived from a crosslinking agent, the weight ratio of the structural units derived from the crosslinking agent to the structural units derived from the compound having a benzene ring containing an amino group (structural units derived from crosslinking agent / structural units derived from the compound having a benzene ring containing an amino group) is preferably 0.1 or more, more preferably 0.5 or more, and even more preferably 1 or more; preferably 10 or less, more preferably 5 or less, and even more preferably 2 or less.

[0036] The content of the black particles in the near-infrared transparent composition may be any content as long as the black particles are the main component, and the proportion of the black particles in the solid content is, for example, preferably 80% by weight or more, more preferably 83% by weight or more, even more preferably 85% by weight or more, still more preferably 90% by weight or more, and preferably 99% by weight or less, more preferably 98.5% by weight or less, still more preferably 98% by weight or less, and still more preferably 91% by weight or less. By setting the content within the above range, it is possible to maintain the blackness and exhibit high light-blocking properties, while improving ease of handling, such as coatability, of the composition.

[0037] The average particle size of the black particles is preferably 0.1 nm or more and 1 μm or less. By setting the average particle size within this range, a uniform coating film can be formed. The average particle size is more preferably 10 nm or more and 100 nm or less.

[0038] The CV value of the particle diameter of the black particles is preferably 15% or less, more preferably 10% or less. By setting it in this range, it is possible to form a more uniform coating film. The lower limit of the CV value of the particle diameter is not particularly limited, and the smaller the better, for example, 0%. The CV value (%) of particle diameter is the value obtained by dividing the standard deviation by the average particle diameter, expressed as a percentage, and is a value calculated by the following formula: The smaller the CV value, the smaller the variation in particle diameter. CV value (%) of particle diameter = (standard deviation of particle diameter / average particle diameter) × 100 The average particle diameter and standard deviation can be determined, for example, by measuring the particle diameters of 100 particles arbitrarily selected from an image obtained using an SEM and calculating the average value.

[0039] The black particles preferably have an average transmittance of 20% or less in the wavelength range of 400 nm or more and less than 800 nm, as measured using a spectrophotometer. This range allows the preparation of a composition that can exhibit extremely high blackness. The average transmittance is more preferably 15% or less, even more preferably 10% or less, and even more preferably 5% or less. The lower limit of the average transmittance is not particularly limited, and the lower the better, for example, 0%. The average transmittance can be determined by measuring the transmittance at each wavelength in the wavelength range of 400 nm or more and less than 800 nm, for example, at 5 nm intervals, and calculating the average value. The transmittance can also be measured, for example, using a spectrophotometer equipped with an integrating sphere and attaching a reflector on the opposite side facing the light incident side. The sample used for measuring the transmittance is a glass plate prepared by mixing the black particles and polyvinyl acetal resin in a 1:2 ratio, dissolving the mixture in a solvent, applying the solution to a glass plate, and drying the solvent to form a 5 μm-thick coating. In this specification, when the term "transmittance" is used simply, it refers to "total light transmittance" and is to be distinguished from "diffuse transmittance" which will be described later.

[0040] The black particles preferably have an average transmittance of 80% or more in the wavelength region of 800 nm or more and less than 2500 nm, as measured using a spectrophotometer. Within this range, a composition exhibiting extremely high transmittance in the near-infrared region can be prepared. The average transmittance is more preferably 90% or more, and even more preferably 95% or more. The upper limit of the average transmittance is not particularly limited, and the higher the value, the more preferable, for example, 100%. The average transmittance can be determined by measuring the transmittance at each wavelength in the wavelength region of 800 nm or more and less than 2500 nm, for example, at 5 nm intervals, using a method similar to that for measuring the average transmittance in the wavelength region of 400 nm or more and less than 800 nm, and calculating the average value of these values.

[0041] Examples of methods for producing the black particles include polymerizing the compound having an aromatic ring containing a hydroxyl group and the compound having a benzene ring containing an amino group to produce an organic black compound, and then adding an oxidizing agent to perform an oxidation treatment. Another example is a method of mixing and reacting a compound having an aromatic ring containing a hydroxyl group, a compound having a benzene ring containing an amino group, and a crosslinking agent to produce an organic black compound, and then adding an oxidizing agent to perform an oxidation treatment. Another example is a method of mixing and reacting a compound having an aromatic ring containing a hydroxyl group, a compound having a benzene ring containing an amino group, a crosslinking agent, and an oxidizing agent. Specifically, a method is used in which a solution containing a compound having an aromatic ring containing a hydroxyl group is prepared, and then a solution containing a compound having a benzene ring containing an amino group is added dropwise to cause a reaction. If necessary, a crosslinking agent solution is added to produce an organic black compound, and then an oxidizing agent solution is added to the resulting compound to perform an oxidation treatment.

[0042] In the above reaction, the weight ratio of the compound having a benzene ring containing an amino group to the compound having an aromatic ring containing a hydroxy group (compound having a benzene ring containing an amino group / compound having an aromatic ring containing a hydroxy group) is preferably 0.1 or more, more preferably 0.2 or more, even more preferably 0.25 or more, even more preferably 0.28 or more, preferably 10 or less, more preferably 5 or less, even more preferably 3.5 or less, even more preferably 1 or less, and particularly preferably 0.5 or less. By setting it within the above range, it is possible to improve visible light blocking properties and near-infrared transmittance.

[0043] In the reaction, the weight ratio of the crosslinking agent to the compound having an aromatic ring containing a hydroxy group (crosslinking agent / compound having an aromatic ring containing a hydroxy group) is preferably 0.1 or more, more preferably 0.2 or more, even more preferably 0.3 or more, still more preferably 0.4 or more, and is preferably 10 or less, more preferably 5 or less, even more preferably 2 or less, still more preferably 1 or less, and particularly preferably 0.5 or less.

[0044] In the reaction, the weight ratio of the crosslinking agent to the compound having a benzene ring containing an amino group (structural units derived from the crosslinking agent / structural units derived from the compound having a benzene ring containing an amino group) is preferably 0.1 or more, more preferably 0.5 or more, even more preferably 1 or more, still more preferably 1.4 or more, and is preferably 10 or less, more preferably 5 or less, even more preferably 2 or less, and still more preferably 1.8 or less.

[0045] The reaction temperature is preferably 10°C or higher, more preferably 20°C or higher, even more preferably 30°C or higher, even more preferably 40°C or higher, and preferably 100°C or lower, more preferably 80°C or lower, even more preferably 70°C or lower, and even more preferably 60°C or lower. The reaction time is preferably 4 hours or higher, more preferably 6 hours or higher, and preferably 72 hours or lower, more preferably 48 hours or lower. By setting the temperature within the above range, the average particle size can be adjusted to a suitable range. The reaction is judged to be complete when 70% by weight or more of the raw materials remaining in the reaction solution have reacted, when the amount of the raw materials remaining in the reaction solution is confirmed. The amount of the remaining raw materials can be confirmed, for example, by heating the reaction solution to a temperature higher than the temperature at which the compound having an aromatic ring containing a hydroxy group and the compound having a benzene ring containing an amino group volatilizes, drying the reaction solution, and measuring the amount of residual solids or by quantitative analysis using gas chromatography.

[0046] In the above reaction, it is preferable to add an additive. Examples of the additive include halogen compounds such as iodine, bromine, and chlorine; protonic acids such as sulfuric acid, hydrochloric acid, nitric acid, perchloric acid, fluoroboric acid, and phosphinic acid; various salts of these protonic acids; Lewis acids such as aluminum trichloride, iron trichloride, molybdenum chloride, antimony chloride, arsenic pentafluoride, and antimony pentafluoride; organic carboxylic acids such as acetic acid, trifluoroacetic acid, polyethylenecarboxylic acid, formic acid, benzoic acid, and citric acid; various salts of these organic carboxylic acids; phenols such as phenol, nitrophenol, and cyanophenol; various salts of these phenols; di-2-ethylhexyl sulfosuccinic acid, sulfosuccinic acid, and the like. salts of sulfosuccinic acids; polymeric acids such as polyacrylic acid; alkyl phosphates such as propyl phosphate, butyl phosphate, and hexyl phosphate; polyalkylene oxide phosphates such as polyethylene oxide dodecyl ether phosphate and polyethylene oxide alkyl ether phosphate; various salts of alkyl phosphates and polyalkylene oxide phosphates; sulfates such as lauryl sulfate, cetyl sulfate, stearyl sulfate, and lauryl ether sulfate; and various salts of these sulfates.

[0047] The temperature during the oxidation treatment is preferably 10° C. or higher, more preferably 20° C. or higher, even more preferably 30° C. or higher, still more preferably 40° C. or higher, and preferably 100° C. or lower, more preferably 80° C. or lower, even more preferably 70° C. or lower, and still more preferably 60° C. or lower. The time during the oxidation treatment is preferably 0.5 hours or higher, more preferably 1 hour or higher, even more preferably 2 hours or higher, still more preferably 4 hours or higher, preferably 24 hours or lower, more preferably 12 hours or lower, even more preferably 10 hours or lower, and still more preferably 8 hours or lower.

[0048] In the oxidation treatment step, the weight ratio of the oxidizing agent to the organic black compound obtained in the step (oxidizing agent / organic black compound) is preferably 0.01 or more, more preferably 0.1 or more, even more preferably 0.2 or more, even more preferably 0.3 or more, and is preferably 10 or less, more preferably 5 or less, even more preferably 3 or less, and even more preferably 1 or less.

[0049] The method for producing the black particles may further include a drying step. The drying temperature in the drying step is preferably 40°C or higher, more preferably 50°C or higher, even more preferably 60°C or higher, and even more preferably 80°C or higher, and is preferably 200°C or lower, more preferably 150°C or lower, even more preferably 120°C or lower, and even more preferably 100°C or lower. The drying time is preferably 1 hour or longer, more preferably 2 hours or longer, even more preferably 3 hours or longer, and even more preferably 4 hours or longer, and is preferably 48 hours or shorter, more preferably 36 hours or shorter, even more preferably 24 hours or shorter, and even more preferably 12 hours or shorter.

[0050] The near-infrared transparent composition contains an additive, which can suppress structural changes of the black particles even when exposed to air or ultraviolet light or visible light for a long period of time, thereby improving storage stability.

[0051] The additive is preferably at least one selected from the group consisting of a radical scavenger and an ultraviolet absorber. By including the additive, the effect of suppressing structural changes in the black particles can be further enhanced, and storage stability can be further improved.

[0052] Examples of the radical scavenger include hindered phenol compounds, hindered amine compounds, nitroxyl-containing polymerization inhibitors, sulfur-containing heterocyclic compounds, conjugated photosensitizers, etc. From the viewpoint of further improving storage stability, the radical scavenger is preferably at least one selected from the group consisting of hindered phenol compounds, hindered amine compounds, nitroxyl-containing polymerization inhibitors, and sulfur-containing heterocyclic compounds.

[0053] Examples of the hindered phenol compounds include 1,3,5-tris(3,5-di-t-butyl-4-hydroxybenzyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, 1,1,3-tris-(2'-methyl-4'-hydroxy-5'-t-butylphenyl)-butane, 4,4'-butylidene-bis-(2-t-butyl-5-methylphenol), 3-(3,5-di-t-butyl-4-hydroxyphenyl)stearyl propionate, pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4 -hydroxyphenyl)]propionate, 3,9-bis[2-[3-(3-t-butyl-4-hydroxy-5-methylphenyl)propionyloxy]-1,1-dimethylethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane, 1,3,5-tris(3,5-di-t-butyl-4-hydroxyphenylmethyl)-2,4,6-trimethylbenzene, 1,3,5-tris(3-hydroxy-4-t-butyl-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, 2,2'-methyl N,N-hexamethylenebis(3,5-di-t-butyl-4-hydroxy-hydrocinnamamide), i-octyl 3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, 4,6-bis(dodecylthiomethyl)-o-cresol, calcium salt of 3,5-di-t-butyl-4-hydroxybenzylphosphonic acid monoethyl ester, 4,6-bis(octylthiomethyl)- o-Cresol, bis[3-(3-methyl-4-hydroxy-5-t-butylphenyl)propionic acid]ethylene bisoxybisethylene, 1,6-hexanediol bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)]propionate, 2,4-bis-(n-octylthio)-6-(4-hydroxy-3,5-di-t-butylanilino)-1,3,5-triazine, 2,2'-thio-bis-(6-t-butyl-4-methylphenol), 2,5-di-t-amyl-hydroquinone, 2,6-di-t-butyl-4-nonylphenol, 2,Examples include 2'-isobutylidene-bis-(4,6-dimethyl-phenol), 2,2'-methylene-bis-(6-(1-methyl-cyclohexyl)-p-cresol), and 2,4-dimethyl-6-(1-methyl-cyclohexyl)-phenol. Commercially available products include Adekastab AO-20, AO-30, AO-40, AO-50, AO-60, AO-80, and AO-330 (manufactured by ADEKA Corporation), KEMINOX 101, 179, 76, and 9425 (manufactured by Chemipro Corporation), IRGANOX 1010, 1035, 1076, 1098, 1135, 1330, 1726, 1425WL, 1520L, 245, 259, 3114, 5057, and 565 (manufactured by BASF Japan), and Cyanox CY-1790 and CY-2777 (manufactured by Sun Chemical Corporation).

[0054] Examples of the hindered amine compound include tetrakis(1,2,2,6,6-pentamethyl-4-piperidyl)1,2,3,4-butanetetracarboxylate, tetrakis(2,2,6,6-tetramethyl-4-piperidyl)1,2,3,4-butanetetracarboxylate, bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate, bis(1-undecanoxy-2,2,6,6-tetramethylpiperidin-4-yl)carbonate, 1,2,2,6,6-pentamethyl-4-piperidyl methacrylate, 2,2,6,6-tetra ... methyl-4-piperidyl methacrylate, polycondensation product of dimethyl succinate and 1-(2-hydroxyethyl)-4-hydroxy-2,2,6,6-tetramethylpiperidine, poly[[6-[(1,1,3,3-tetramethylbutyl)amino]-s-triazine-2,4-diyl]-[(2,2,6,6-tetramethyl-4-piperidyl)imino]-hexamethylene-[(2,2,6,6-tetramethyl-4-piperidyl)imino]], ester of 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol and 3,5,5-trimethylhexanoic acid N,N'-4,7-tetrakis[4,6-bis{N-butyl-N-(1,2,2,6,6-pentamethyl-4-piperidyl)amino}-1,3,5-triazin-2-yl]-4,7-diazadecane-1,10-diamine, decanedioic acid bis(2,2,6,6-tetramethyl-1-(octyloxy)-4-piperidinyl) ester, reaction products of 1,1-dimethylethyl hydroperoxide with octane, bis(1,2,2,6,6-pentamethyl-4-pyridyl)[[3,5-bis(1,1dimethylethyl)-4-hydroxyphenyl]methyl] Butyl malonate, methyl 1,2,2,6,6-pentamethyl-4-pyripridyl sebacate, poly[[6-morpholino-s-triazine-2,4-diyl]-[(2,2,6,6-tetramethyl-4-piperidyl)imino]-hexamethylene-[(2,2,6,6-tetramethyl-4-piperidyl)imino]], 2,2,6,6-tetramethyl-4-piperidyl-C12-21 and C18 unsaturated fatty acid esters, N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl)-1,6-hexamethylenediamine, 2-methyl-2-(2,2,6,6-tetramethyl-4-piperidyl)amino-N-(2,2,6,6-tetramethyl-4-piperidyl)propionamide, and the like. Commercially available products include Adekastab LA-52, LA-57, LA-63P, LA-68, LA-72, LA-77Y, LA-77G, LA-81, LA-82, LA-87, LA-402F, and LA-502XP (all manufactured by ADEKA Corporation), KAMISTAB 29, 62, 77, and 94 (all manufactured by Chemipro Kasei Co., Ltd.), Tinuvin 249, TINUVIN 111FDL, 123, 144, 292, and 5100 (all manufactured by BASF Japan Ltd.), and Cyasorb UV-3346, UV-3529, and UV-3853 (all manufactured by Sun Chemical Co., Ltd.).

[0055] Examples of the nitroxyl-containing polymerization inhibitor include di-tert-butyl nitroxide, 2,2,6,6-tetramethylpiperidine-1-oxyl, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl, 4-oxo-2,2,6,6-tetramethylpiperidine-1-oxyl, 4-amino-2,2,6,6-tetramethylpiperidine-1-oxyl, 4-methoxy-2,2,6,6-tetramethylpiperidine-1-oxyl, 4-acetoxy-2,2,6,6-tetramethylpiperidine-1-oxyl, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl, and bis(2,2,6,6-tetramethyl-4-piperidyl-1-oxyl)sebacate.

[0056] Examples of the sulfur-containing heterocyclic compounds include thiophene, tetrahydrothiophene, thiane (tetrahydrothiopyran), 2,1,3-benzothiadiazole, dibenzothiophene, and 2-ethylthiophenothiazine.

[0057] Examples of the ultraviolet absorber include benzotriazole-based compounds, triazine-based compounds, benzophenone-based compounds, etc. From the viewpoint of further improving storage stability, the ultraviolet absorber is preferably at least one selected from the group consisting of benzotriazole-based compounds, triazine-based compounds, and benzophenone-based compounds.

[0058] Examples of the benzotriazole compounds include 2-(2-hydroxy-5-methylphenyl)benzotriazole, 2-(2-hydroxy-5-tert-octylphenyl)benzotriazole, 2-(2-hydroxy-3,5-di-tert-butylphenyl)-5-chlorobenzotriazole, 2-(2-hydroxy-3-tert-butyl-5-methylphenyl)-5-chlorobenzotriazole, 2-(2-hydroxy-3,5-dicumylphenyl)benzotriazole, 2,2'-methylenebis[4-tert-octyl-6-(2H-benzotriazol-2-yl)phenol], 2,2'-methylenebis(4-tert-octyl-6-benzotriazolylphenol), 2,2'-methylenebis(4-ethylhydroxy-6-benzotriazolylphenol), 2,2'-methylenebis(4-methyl-6-benzotriazolylphenol), polyethylene glycol ester of 2-(2-hydroxy-3-tert-butyl-5-carboxyphenyl)benzotriazole, 2-[2-hydroxy-3-(2-acryloyloxyethyl)-5-methylphenyl]benzotriazole, 2-[2-hydroxy-3-(2-methacryloyloxyethyl)-5-tert-butylphenyl]benzotriazole, 2-[2-hydroxy-3-(2-methacryloyloxyethyl)-5-tert-octylphenyl]benzotriazole, 2-[2-hydroxy-3-(2-methacryloyloxyethyl)-5-tert-butylphenyl]-5-chlorobenzotriazole, 2-[2-hydroxy-5-(2-methacryloyloxyethyl)phenyl]benzotriazole and 2-(2-hydroxyphenyl)benzotriazole compounds such as benzotriazole, 2-[2-hydroxy-3-tert-butyl-5-(2-methacryloyloxyethyl)phenyl]benzotriazole, 2-[2-hydroxy-3-tert-amyl-5-(2-methacryloyloxyethyl)phenyl]benzotriazole, 2-[2-hydroxy-3-tert-butyl-5-(3-methacryloyloxypropyl)phenyl]-5-chlorobenzotriazole, 2-[2-hydroxy-4-(2-methacryloyloxymethyl)phenyl]benzotriazole, 2-[2-hydroxy-4-(3-methacryloyloxy-2-hydroxypropyl)phenyl]benzotriazole, and 2-[2-hydroxy-4-(3-methacryloyloxypropyl)phenyl]benzotriazole.

[0059] Examples of the triazine compounds include 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-(hexyloxy)phenol, 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-(octyloxy)phenol, 2-(4,6-bis(4-butoxy-2-methylphenyl)-1,3,5-triazin-2-yl)-3,5-dibutoxyphenol, 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine-2 phenol-containing triazine compounds such as 2-(4,6-di([1,1'-biphenyl]-4-yl)-1,3,5-triazin-2-yl)-5-hexyloxyphenol and 2-methylhexyl-2-(4,(4,6-di([1,1'-biphenyl]-4-yl)-1,3,5-triazin-2-yl)-3-hydroxyphenoxy)propanoate.

[0060] Examples of the benzophenone compounds include 2-hydroxybenzophenone compounds such as 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,4-dihydroxybenzophenone, 5,5'-methylenebis(2-hydroxy-4-methoxybenzophenone), and 1,4-bis(4-benzoyl-3-hydroxyphenoxy)-butane.

[0061] The content of the additive in the near-infrared transparent composition is preferably 0.1 parts by weight or more, more preferably 0.5 parts by weight or more, even more preferably 1 part by weight or more, still more preferably 2 parts by weight or more, and is preferably 30 parts by weight or less, more preferably 20 parts by weight or less, still more preferably 10 parts by weight or less, and still more preferably 5 parts by weight or less, relative to 100 parts by weight of the black particles.

[0062] The content of the additive in the near-infrared transparent composition is preferably 0.1 parts by weight or more, more preferably 0.5 parts by weight or more, even more preferably 1 part by weight or more, still more preferably 2 parts by weight or more, and is preferably 30 parts by weight or less, more preferably 20 parts by weight or less, still more preferably 10 parts by weight or less, and still more preferably 5 parts by weight or less, based on 100 parts by weight of the solid content.

[0063] The near-infrared ray transmitting composition may further contain other additives such as an organic solvent, a reactive diluent, a spacer, a curing accelerator, an antifoaming agent, and a leveling agent, if necessary.

[0064] The near-infrared transparent composition has an average transmittance of 20% or less in a wavelength range of 400 nm or more and less than 800 nm, as measured using a spectrophotometer. By satisfying the above, high light-blocking properties can be achieved in the visible light range. The average transmittance is preferably 15% or less, more preferably 10% or less. Furthermore, the lower the average transmittance, the more preferable it is, for example, 0% or more. The average transmittance can be determined, for example, by measuring the transmittance at each wavelength in the range of 400 nm or more and less than 800 nm at intervals of, for example, 5 nm, and calculating the average value. The transmittance can be measured, for example, using a spectrophotometer equipped with an integrating sphere and attaching a reflector on the opposite side facing the light incident side. Furthermore, as a sample for measuring the transmittance, for example, for the near-infrared transparent composition, the near-infrared transparent composition and the polyvinyl acetal resin are mixed so that the weight ratio of the black particles to the polyvinyl acetal resin is 1:1, the mixture is dissolved in a solvent, and the solution is applied to a glass plate to form a coating film with a thickness of 5 μm. The average transmittance of the near-infrared transmitting composition can be adjusted by the composition of the black particles, the type and content of the additives, and the like.

[0065] The near-infrared transparent composition has an average transmittance of 80% or more in a wavelength region of 850 nm or more and less than 2500 nm, as measured using a spectrophotometer. By satisfying the above, high transmittance can be exhibited in the near-infrared region. The average transmittance is more preferably 90% or more, and even more preferably 95% or more. The higher the average transmittance, the more preferable it is, for example, 100% or less. The average transmittance can be determined by measuring the transmittance at each wavelength in the wavelength region of 850 nm or more and less than 2500 nm, for example, at 5 nm intervals, using a method similar to that for measuring the average transmittance in the wavelength region of 400 nm or more and less than 800 nm, and calculating the average value of these. The average transmittance of the near-infrared transparent composition can be adjusted by the composition of the black particles, the type and content of the additive, etc.

[0066] The near-infrared transparent composition preferably has a lower ratio of the average transmittance in a wavelength region of 850 nm or more and less than 2500 nm to the average transmittance in a wavelength region of 400 nm or more and less than 800 nm (average transmittance in a wavelength region of 400 nm or more and less than 800 nm / average transmittance in a wavelength region of 850 nm or more and less than 2500 nm), and the lower limit is, for example, 0.

[0067] In a weather resistance deterioration acceleration test using a super xenon weather meter, the near-infrared transmitting composition was exposed to ultraviolet light with a wavelength of 300 nm or more and 400 nm or less for 300 hours, and the transmittance at a wavelength λ nm measured using a spectrophotometer was T λ and T λ（３００ｈ） When |T| is set, it is preferable that the following formulas (a) to (d) are satisfied. ６５０（３００ｈ） -T ６５０ |<30 (b): |T ９０５（３００ｈ） -T ９０５ |<15 (c): |T ９４０（３００ｈ） -T ９４０ |<15 (d): |T １５５０（３００ｈ） -T １５５０|<15 By satisfying the above relationship, a near-infrared transmitting composition with excellent light stability can be obtained. The above formula (a) is more preferably less than 27, and even more preferably less than 10. The above formula (b) is more preferably less than 12, and even more preferably less than 10. The above formula (c) is more preferably less than 10, and even more preferably less than 6. The above formula (d) is more preferably less than 10, and even more preferably less than 5. The weather resistance deterioration accelerated test can be carried out, for example, at a temperature of 50°C, a relative humidity of 50% RH, and a radiation intensity of 60 W / cm. ２ The near-infrared ray transmitting composition can be exposed to light at a black panel temperature of 63° C. The transmittance of the near-infrared ray transmitting composition after exposure can be adjusted by the composition of the black particles, the type and content of the additives, etc.

[0068] The near-infrared transmitting composition has a diffuse transmittance T in the wavelength region of 850 nm or more and less than 2500 nm as measured with a spectrophotometer. ｄ It is preferable that the maximum value of is 10% or less. By satisfying the above, diffusion of near-infrared rays is suppressed, the use efficiency of transmitted near-infrared rays is increased, and near-infrared rays can be effectively utilized. The maximum value of the diffuse transmittance is more preferably 3% or less, and even more preferably 1% or less. The lower the diffuse transmittance, the more preferable it is, for example, 0% or more. The diffuse transmittance can be measured, for example, using a spectrophotometer equipped with an integrating sphere, by removing the reflector on the opposite side facing the light incident side, and setting it so that only diffused light remains within the integrating sphere. The diffuse transmittance of the near-infrared transmitting composition can be adjusted by the composition of the black particles, the type and content of additives, etc.

[0069] In a weather resistance deterioration acceleration test using a super xenon weather meter, the near-infrared transmitting composition was exposed to ultraviolet light with a wavelength of 300 nm or more and 400 nm or less for 300 hours, and the diffuse transmittance T ｄ（３００ｈ）It is preferable that the maximum value of is 10% or less. By satisfying the above, diffusion of near-infrared rays is suppressed, the use efficiency of transmitted near-infrared rays is increased, and it is possible to effectively utilize near-infrared rays. The maximum value of the diffuse transmittance is more preferably 3% or less, and even more preferably 1% or less. The lower the diffuse transmittance, the more preferable it is, for example, 0% or more. The diffuse transmittance of the near-infrared transmitting composition after exposure can be adjusted by the composition of the black particles, the type and content of the additive, etc.

[0070] Examples of a method for producing the near-infrared transparent composition include a method of mixing black particles, additives, and the like using a mixer such as a homodisper, a homomixer, a universal mixer, a planetary mixer, a kneader, a three-roll mill, a rotation-revolution mixer, or an ultrasonic irradiator.

[0071] The near-infrared transparent composition can be used in applications such as coating films for optical films, black paints, black matrices for color filters, and inks for infrared sensors. That is, the near-infrared transparent composition can be used to prepare coating films for optical films, black paints, black matrices for color filters, inks for infrared sensors, and the like, each containing the near-infrared transparent composition. In particular, the near-infrared transparent composition can achieve both light-blocking properties in the visible light region and transmittance in the near-infrared region. Furthermore, it can suppress structural changes in the black particles even when exposed to air for a long period of time or to relatively high-energy ultraviolet or visible light. Therefore, the near-infrared transparent composition can be used in applications such as optical films suitable for near-infrared sensors for smartphones, automobiles, and near-infrared cameras. When the near-infrared transparent composition is used to prepare coating films, black paints, black matrices for color filters, inks for infrared sensors, and the like, the light transmittance is affected by the dispersion medium and dispersion method of the near-infrared transparent composition, the binder resin for forming the coating film, the particle content, and the coating film thickness. However, a hydrophilic to hydrophobic solvent can be selected as the dispersion medium. The particle content is preferably 20 parts by weight or more of particles per 100 parts by weight of the binder resin. The coating thickness is preferably 30 μm or less, more preferably 20 μm or less, even more preferably 10 μm or less, and even more preferably 5 μm or less. The near-infrared transparent composition has excellent light-shielding properties in the visible light region, so that sufficient light-shielding properties can be exhibited even when the coating film is thin, and by thinning the coating film, the amount of black particles containing an organic black compound and the amount of solvent used can be reduced.

[0072] For example, an ink can be prepared by mixing the near-infrared transparent composition, a solvent, a binder resin, etc. Furthermore, a molded article such as an optical film can be obtained by applying the ink onto a substrate, drying it, removing the solvent, or otherwise molding it.

[0073] The content of the black particles in the ink is, for example, preferably 5 wt % or more, preferably 40 wt % or less, and more preferably 20 wt % or less, which can maintain the blackness and exhibit high light-blocking properties, while improving ease of handling, such as coatability, of the composition.

[0074] Examples of the binder resin include polyvinyl acetal resins such as polyvinyl formal resin and polyvinyl butyral resin, (meth)acrylic resins, (meth)acrylic urethane resins, urethane resins, polyvinyl chloride resins, melamine resins, styrene resins, epoxy resins, and polyester resins.

[0075] Examples of a method for producing the optical film include a method in which the near-infrared transparent composition, a binder resin, a solvent, and the like are mixed using a stirrer or the like to prepare a solution containing the near-infrared transparent composition, which is then applied onto a substrate and dried.

[0076] The method for forming the black matrix involves first mixing the near-infrared transparent composition, the curable compound, and optionally a curing agent, a solvent, and the like using a stirrer to prepare a solution containing the near-infrared transparent composition. The solution is then applied to a substrate and dried to form a coating film. The resulting coating film is partially exposed to active energy rays such as ultraviolet light or excimer laser light through a negative mask, thereby forming a black matrix having a predetermined pattern.

[0077] Furthermore, the above-described method for forming a black matrix can be performed on a photosensitive resin composition having a dispersed red pigment, a photosensitive resin composition having a dispersed green pigment, and a photosensitive resin composition having a dispersed blue pigment to form pixel patterns of each color, thereby forming a color filter. The photosensitive resin composition having a dispersed red pigment, the photosensitive resin composition having a dispersed green pigment, and the photosensitive resin composition having a dispersed blue pigment may be any conventionally known composition. The color filter can also be produced by ejecting red, green, and blue inks from inkjet nozzles into each region defined by the black matrix and curing the accumulated inks with heat or light. The color filter can be suitably used as a component of a display device such as a liquid crystal display device or an organic electroluminescence display device.

[0078] The near-infrared transmitting composition can be suitably used in the production of electronic devices, and can be suitably used as a sealant for liquid crystal display elements. Furthermore, by blending conductive fine particles with the sealant for liquid crystal display elements, a vertically conductive material can be produced. Furthermore, a liquid crystal display element can be produced using the sealant for display elements.

[0079] The conductive fine particles may be metal balls, fine resin particles with a conductive metal layer formed on the surface thereof, etc. Among these, fine resin particles with a conductive metal layer formed on the surface thereof are preferred because they have excellent elasticity and can provide conductive connection without damaging transparent substrates, etc.

[0080] The sealant for liquid crystal display elements can be suitably used in the manufacture of liquid crystal display elements by a liquid crystal dropping method. Examples of methods for manufacturing liquid crystal display elements by the liquid crystal dropping method include the following. First, a process is performed in which the sealant for liquid crystal display elements is applied to a substrate to form a frame-shaped seal pattern. Next, a process is performed in which, while the sealant for liquid crystal display elements is still uncured, minute droplets of liquid crystal are dropwise applied to the entire frame of the seal pattern, and another substrate is immediately superimposed. A liquid crystal display element can then be obtained by a process in which the sealant is photocured by irradiating the seal pattern with light. By using the sealant for liquid crystal display elements, the irradiated light can be long-wavelength light such as infrared light, which can mitigate damage to peripheral components due to light irradiation. Furthermore, the sealant can be photocured sufficiently even when placed in a light-shielding area.

[0081] According to the present invention, it is possible to provide a near-infrared transmitting composition that can achieve both light-shielding properties in the visible light region and transmittance in the near-infrared region and has excellent storage stability.

[0082] 1 is a graph (horizontal axis: wavelength, vertical axis: transmittance) obtained when total light transmittance was measured for the coating films obtained in Examples 1 to 9. 2 is a graph (horizontal axis: wavelength, vertical axis: transmittance) obtained when total light transmittance was measured for the coating film obtained in Comparative Example 1. 3 is a graph (horizontal axis: wavelength, vertical axis: transmittance) obtained when total light transmittance was measured for the coating films obtained in Examples 1 to 9 after an accelerated weathering degradation test. 4 is a graph (horizontal axis: wavelength, vertical axis: transmittance) obtained when total light transmittance was measured for the coating film obtained in Comparative Example 1 after an accelerated weathering degradation test.

[0083] The following examples will further illustrate the present invention, but the present invention is not limited to these examples.

[0084] Example 1: A 1-naphthol solution was obtained by adding 0.98 g of 1-naphthol (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) to a mixture of 0.07 L of water and stirring. Furthermore, 0.28 g of N,N-dimethyl-1,4-phenylenediamine (manufactured by Tokyo Chemical Industry Co., Ltd.) was mixed with the 1-naphthol solution to obtain a mixture. The resulting mixture was stirred at room temperature (25°C) for 0.5 hours, then heated to 41°C and stirred for an additional 3 hours. 0.42 g of 1,3,5-trioxane (manufactured by Tokyo Chemical Industry Co., Ltd.) was added and stirred for 3 hours. The mixture was then heated to 53°C and stirred for an additional 6 hours, and then cooled to room temperature to obtain a particle dispersion. 0.50 g of benzoquinone (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) and 0.050 g of hydrogen peroxide (manufactured by Santoku Chemical Co., Ltd.) were added to the resulting particle dispersion, and the mixture was then heated to 41°C and stirred for an additional 5 hours to perform an oxidation treatment. The resulting oxidation-treated particle dispersion was subjected to solid-liquid separation and then vacuum-dried at 65°C for 5 hours to obtain black particles containing an organic black compound oxidized by an oxidizing agent, the organic black compound having a structural unit derived from a compound having an aromatic ring containing a hydroxyl group and a structural unit derived from a compound having a benzene ring containing an amino group.

[0085] 0.100 g of the resulting black particles was weighed into a sample bottle, and 0.400 g of Solfit (3-methoxy-3-methyl-1-butanol, manufactured by Kuraray Co., Ltd.) was added. The mixture was mixed by shaking with a vibrator for several seconds, and then ultrasonicated at 28 kHz for 30 minutes to obtain a black particle solution. 0.500 g of a Solfit solution containing 0.4 wt % of additive and 20 wt % of polyvinyl butyral resin (S-LEC BL-5Z, manufactured by Sekisui Chemical Co., Ltd.) was added to the resulting solution. The mixture was mixed by shaking with a vibrator for several seconds, and then ultrasonicated at an upper limit of 28 kHz for 30 minutes to obtain a coating solution containing a near-infrared transparent composition. The additive used was Tinuvin 360 (a benzotriazole-based compound, manufactured by BASF Japan). The obtained coating liquid was applied to a slide glass with a coater so that the film thickness after drying would be 5 μm, and dried at 90° C. to form a coating film (film thickness 5 μm) on the slide glass.

[0086] Example 2 A coating liquid and a coating film containing a near-infrared transmitting composition were obtained in the same manner as in Example 1, except that Tinuvin 1577 (a triazine-based compound manufactured by BASF Japan) was used as the additive.

[0087] Example 3 A coating liquid and a coating film containing a near-infrared transmitting composition were obtained in the same manner as in Example 1, except that 2,2'-dihydroxy-4,4'-dimethoxybenzophenone (a benzophenone-based compound manufactured by Tokyo Chemical Industry Co., Ltd.) was used as the additive.

[0088] Example 4 A black particle solution was prepared using 0.050 g of black particles. A coating liquid and a coating film containing a near-infrared transparent composition were prepared in the same manner as in Example 1, except that Irganox 1010 (a hindered phenol compound manufactured by BASF Japan) was used as the additive, 0.250 g of a solfit solution in which 2 wt % of the additive and 20 wt % of a polyvinyl butyral resin were dissolved, and 0.200 g of solfit was further added.

[0089] Example 5 A black particle solution was prepared using 0.050 g of black particles. A coating solution and a coating film containing a near-infrared transparent composition were prepared in the same manner as in Example 4, except that Tinuvin 292 (a hindered amine compound manufactured by BASF Japan Ltd.) was used as the additive.

[0090] Example 6 A black particle solution was obtained by using 0.100 g of cyclohexane instead of 0.400 g of Solfit, and adjusting the amount of black particles to 0.050 g. A coating liquid and a coating film containing a near-infrared transparent composition were obtained in the same manner as in Example 1, except that bis(2,2,6,6-tetramethyl-4-piperidyl-1-oxyl) sebacate (a hindered amine compound manufactured by Tokyo Chemical Industry Co., Ltd.) was used as the additive, and 0.250 g of a cyclohexanone solution in which 4 wt % of the additive and 20 wt % of a polyvinyl butyral resin were dissolved was used.

[0091] Example 7 A coating liquid and a coating film containing a near-infrared transparent composition were obtained in the same manner as in Example 1, except that 2,1,3-benzothiadiazole (manufactured by Tokyo Chemical Industry Co., Ltd., a sulfur-containing heterocyclic compound) was used as the additive, and 0.500 g of a solfit solution in which 2% by weight of the additive and 20% by weight of a polyvinyl butyral resin were dissolved was used.

[0092] Example 8 A coating liquid and a coating film containing a near-infrared transmitting composition were obtained in the same manner as in Example 7, except that dibenzothiophene (manufactured by Tokyo Chemical Industry Co., Ltd., a sulfur-containing heterocyclic compound) was used as the additive.

[0093] Example 9 A coating liquid and a coating film containing a near-infrared transmitting composition were obtained in the same manner as in Example 7, except that 2-ethylthiophenothiazine (manufactured by Tokyo Chemical Industry Co., Ltd., a sulfur-containing heterocyclic compound) was used as the additive.

[0094] Comparative Example 1 A black particle solution was prepared using 0.050 g of black particles. A coating solution and a coating film were prepared in the same manner as in Example 1, except that no additive was used, 0.250 g of a 20 wt % SOLFITE solution of polyvinyl butyral resin was used, and 0.200 g of SOLFITE was further added.

[0095] (Evaluation) The coating films obtained in the examples and comparative examples were evaluated as follows. The results are shown in Table 1.

[0096] (1) Total Light Transmittance The light transmittance of the obtained coating film in the wavelength range of 200 to 2500 nm was measured using a spectrophotometer with an integrating sphere (Hitachi, U-4100 model). During the measurement, a reflector was attached on the opposite side of the light incident side to measure the total light transmittance. The measurement conditions were set as follows: [Measurement mode: wavelength scan, Data mode: %T, Start wavelength: 2500.00 nm, End wavelength: 200.00 nm, Scan speed: 600 nm / min, Sampling interval: 5.00 nm, Initial waiting time: 0 s, Repeat period: 0.0 min, Number of measurements: 1, Auto-zero before measurement: OFF, Slit: 8.00 nm, Photomultiplier voltage: Automatic 1, Light source switching mode: Automatic switching, Light source switching wavelength: 340.00 nm, Base Baseline settings: User 1, High resolution measurement: OFF, D2 lamp: On, W1 lamp: On, R / S inversion: OFF, Light attenuation rate: Light attenuation plate not used], Near infrared; Scan speed: 750 nm, Slit: Automatic control, PbS sensitivity: 2, Detector switching correction: No correction, Detector switching wavelength: 850.0 nm, Light intensity control mode: Fixed], Peak detection; Detection method: Rectangular, Sensitivity: 1, Threshold: 0.01]

[0097] Next, the transmittance values ​​measured at 5 nm intervals were used to calculate the average transmittance in the wavelength region of 400 nm or more and less than 800 nm (400 to 795 nm) and the average transmittance in the wavelength region of 850 nm or more and less than 2500 nm (850 to 2495 nm), thereby determining the average transmittance.

[0098] (2) Evaluation of Deterioration The resulting coating film was subjected to an accelerated weathering test using a super xenon weather meter (SX-75 manufactured by Suga Test Instruments Co., Ltd.) at a temperature of 50°C, a relative humidity of 50% RH, and a radiation intensity of 60 W / cm. ２ The sample was exposed to ultraviolet light of 300 nm or more and 400 nm or less for 300 hours under the condition of a black panel temperature of 63°C. The total light transmittance after 300 hours of exposure was measured in the same manner as in "(1) Total Light Transmittance". The transmittances before and after exposure were measured as T λ and T λ（３００ｈ） The change in transmittance before and after exposure was calculated based on the following formula and evaluated based on the following criteria: (a): |T ６５０（３００ｈ）-T ６５０ | (b): | T ９０５（３００ｈ） -T ９０５ | (c): | T ９４０（３００ｈ） -T ９４０ | (d): | T １５５０（３００ｈ） -T １５５０ | ◎: Meets all of the following: (a) is 10 or less, (b) is 10 or less, (c) is 6 or less, and (d) is 5 or less. 〇: Does not meet the conditions of ◎, and meets all of the following: (a) is 30 or less, (b) is 15 or less, (c) is 15 or less, and (d) is 15 or less. ×: Does not meet the conditions of ◎ and 〇.

[0099] (3) Diffuse transmittance The diffuse transmittance of the obtained coating film was measured by removing the reflector on the side opposite to the light incident side of an integrating sphere spectrophotometer (Hitachi, Ltd., U-4100 model) so that only diffused light remained within the integrating sphere while preventing parallel light from remaining within the integrating sphere. The diffuse transmittance was also measured in the same manner for the coating film after 300 hours of exposure in "(2) Degradation Evaluation." It can be said that a low diffuse transmittance can provide a more precise optical film for near-infrared sensors and near-infrared cameras.

[0100]

[0101] According to the present invention, it is possible to provide a near-infrared transmitting composition that can achieve both light-shielding properties in the visible light region and transmittance in the near-infrared region and has excellent storage stability.

Claims

1. A near-infrared transmitting composition comprising black particles including an organic black compound and an additive, the composition having an average transmittance of 20% or less in the wavelength region of 400 nm or more and less than 800 nm, and an average transmittance of 80% or more in the wavelength region of 850 nm or more and less than 2500 nm, as measured using a spectrophotometer.

2. In a weather resistance deterioration accelerated test using a super xenon weather meter, the material was exposed to ultraviolet light with a wavelength of 300 nm or more and 400 nm or less for 300 hours. The transmittance at a wavelength of λ nm measured using a spectrophotometer before and after exposure was T λ and T λ（３００ｈ） The near infrared ray transmitting composition according to claim 1 , which satisfies the following formulas (a) to (d) when |T ６５０（３００ｈ） -T ６５０ |<30 (b): |T ９０５（３００ｈ） -T ９０５ |<15 (c): |T ９４０（３００ｈ） -T ９４０ |<15 (d): |T １５５０（３００ｈ） -T １５５０ |<15 3. Diffuse transmittance T in the wavelength range of 850 nm or more and less than 2500 nm measured using a spectrophotometer ｄ The near infrared ray transmitting composition according to claim 1 or 2, wherein the maximum value is 10% or less.

4. In a weather resistance deterioration accelerated test using a super xenon weather meter, the diffuse transmittance T after exposure to ultraviolet light with a wavelength of 300 nm or more and 400 nm or less was measured using a spectrophotometer in the wavelength range of 850 nm or more and less than 2500 nm when the material was exposed for 300 hours. ｄ（３００ｈ） The near infrared ray transmitting composition according to claim 1 , 2 or 3 , wherein the maximum value is 10% or less.

5. A near infrared ray transmitting composition according to claim 1, 2, 3 or 4, wherein the additive is at least one selected from the group consisting of radical scavengers and ultraviolet absorbing agents.

6. The near infrared ray transmitting composition according to claim 5, wherein the radical scavenger is at least one member selected from the group consisting of hindered phenol compounds, hindered amine compounds, nitroxyl-containing polymerization inhibitors and sulfur-containing heterocyclic compounds.

7. The near infrared ray transmitting composition according to claim 5 or 6, wherein the ultraviolet absorbing agent is at least one selected from the group consisting of benzotriazole-based compounds, triazine-based compounds and benzophenone-based compounds.

8. The near infrared transmitting composition according to claim 1, 2, 3, 4, 5, 6 or 7, wherein the organic black compound has a structural unit derived from a compound having an aromatic ring containing a hydroxyl group, and a structural unit derived from a compound having a benzene ring containing an amino group.

9. The near infrared ray transmitting composition according to claim 8, wherein the organic black compound has a crosslinking agent or a constitutional unit derived from the crosslinking agent.

10. The near infrared transparent composition of claim 8, wherein the organic black compound comprises an auxochrome.

11. An ink comprising the near-infrared transparent composition according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10, a solvent and a binder resin.

Images