JP5429114B2 - Infrared transmitting black film, substrate with film using infrared transmitting black film, and image display device - Google Patents

Description

  The present invention relates to an infrared transmitting black film capable of shielding visible light and transmitting infrared light, and a film-coated substrate and an image display device using the infrared transmitting black film. More specifically, the light having a wavelength of 380 nm to 800 nm, which is visible light, is blocked to exhibit black color, while the light having a wavelength of 800 nm to 2500 nm, which is a near infrared light, has a transmittance of a certain value or more. The present invention relates to a substrate with a film using an infrared transmission film and an infrared transmission black film that can be suitably used for an infrared transmission filter, a black matrix, and the like, and an image display device using the infrared transmission black film.

  Usually, a signal of a wireless remote controller (remote controller) or the like uses a 950 nm wavelength LED, and industrially uses a 1064 nm band fiber laser or the like. For these signal sources and light receiving elements, it is common to provide a cover using a member that shields visible light and transmits infrared light such as near infrared light from the viewpoint of preventing malfunction due to visible light and appearance. It is. For this reason, an infrared transmitting black film having sufficient transparency with respect to light having a wavelength from near infrared to infrared used, or an infrared transmitting using the infrared transmitting black film, although the appearance is black. A filter is needed.

In the next generation of liquid crystal panels, the COA (color filter on array) method in which a black matrix is directly formed on the array side or the BOA (black matrix on array) method is considered to be the mainstream. In order to produce a black matrix that is a black film by patterning the black coating dry film formed on the array side, it is necessary to align the black matrix pattern directly with respect to the array. For this alignment, an infrared ray of 850 to 950 nm is used. Therefore, in order to read an alignment signal, a black coating dry film that transmits light in this wavelength region is desired as a black matrix material.
In the case of a black matrix member, optical density (OD value: Optical Density) is generally used as an index of transmittance. This is expressed by the following formula (1), where T (%) is the transmittance of the membrane.
OD = −log (T / 100) (1)
In general, in the case of a black matrix member, an OD value per 1 μm thickness is often used as a light shielding index.

In conventional black films, metallic materials such as carbon black, titanium black (titanium oxynitride), iron oxide, chromium and silver fine particles and inorganic materials are mainly used as black materials. A black film formed using a material dispersed in an organic resin or an inorganic resin is known (see, for example, Patent Documents 1 and 2).
In addition, an infrared transmission filter using an organic pigment or dye as a black material has been proposed (see, for example, Patent Documents 3 and 4).

JP-A-5-127433 JP 2005-189561 A JP 2005-67007 A JP 2005-257721 A

However, metallic materials and inorganic materials such as carbon black, titanium black, iron oxide, chromium and silver fine particles have no wavelength dependency in their light absorption ability, or even if they have these, the amount of change is small. In a black film formed using a material in which a black material is dispersed in an organic resin or an inorganic resin, the transmittance in all wavelength regions including the infrared region such as the near infrared region can be improved by improving the visible light shielding property. Decreases, and there is a problem that it does not function as an infrared transmitting black film.
In addition, when an organic pigment or dye is used as the black material, the organic pigment or dye may be decomposed or deteriorated by sunlight or ultraviolet light from a fluorescent lamp, for example, fading of a filter using these may occur. There are concerns.

  The present invention has been made in view of such a situation. An infrared transmitting black film having excellent light-shielding properties with respect to visible light and having a transmittance of a certain value or more with respect to infrared light, and the infrared transmitting black film. An object of the present invention is to provide a substrate with a film using the above and an image display device using the infrared transmitting black film.

  As a result of intensive studies to solve the above problems, the inventor dispersed silver tin alloy fine particles and a mixture of silver particles in an organic resin, an inorganic resin, or a mixture thereof, and an average dispersion thereof. It has been found that when the particle diameter is 1 nm or more and 100 nm or less, light having a wavelength in the infrared region such as the near infrared region of 800 nm or more is transmitted while having high visible light shielding properties.

That is, the present invention
[1] A black material and a resin component are included, the average dispersed particle diameter in the film of the black material is 1 nm or more and 100 nm or less, and the transmittance (T ₅₆₀ ) per 1 μm thickness at a wavelength of 560 nm is less than 40%. And the ratio of the optical density based on the transmittance at a wavelength of 560 nm (OD ₅₆₀ ) and the optical density based on the transmittance at a wavelength of 950 nm (OD ₉₅₀ ) (OD ₉₅₀ / OD ₅₆₀ ) is 0.35 or less. Black film,
[2] Ratio of optical density (OD ₅₆₀ ) based on transmittance at a wavelength of 560 nm to optical density (OD _NIR ) based on transmittance at each wavelength in the near infrared (NIR) wavelength region of wavelength from 800 nm to 2500 nm ( OD _NIR / OD ₅₆₀ ) of the infrared transmitting black film according to the above [1], which is 0.40 or less,
[3] The infrared transmitting black film according to [1] or [2], wherein the volume fraction of the black material is 1.0% by volume or more and 25% by volume or less,
[4] The infrared transmitting black film according to any one of [1] to [3], wherein the black material is fine metal particles mainly composed of silver and tin.
[5] The metal fine particles are silver tin alloy fine particles or a mixed fine particle of silver tin alloy fine particles and silver fine particles, and the silver component content relative to the total amount of silver and tin in the silver tin alloy fine particles is 45% by mass or more. Infrared transmission as described in [4] above, wherein the content of the silver component with respect to the total amount of silver and tin in the mixed fine particles of the silver-tin alloy fine particles and the silver fine particles is not less than 95% by mass and not greater than 45% by mass Black film,
[6] The film-coated substrate having the infrared transmitting black film according to any one of [1] to [5], and [7] The infrared transmitting black according to any one of [1] to [5]. An image display device having a film,
Is to provide.

  According to the present invention, an infrared transmitting black film having excellent light-shielding properties for visible light and having a transmittance of a certain value or more for infrared light, and a film using the infrared transmitting black film A substrate and an image display device using the infrared transmitting black film can be provided.

2 is an electron microscope observation photograph of a cross section of an infrared light transmitting black film obtained in Example 1. FIG. 4 is an electron microscopic observation photograph of a black film cross section obtained in Comparative Example 1. FIG.

Hereinafter, the present invention will be described with reference to embodiments.
[Infrared transmitting black film]
The infrared transmitting black film of the present embodiment (hereinafter sometimes simply referred to as “black film”) includes a black material and a resin component, and the average dispersed particle size in the film of the black material is 1 nm or more and 100 nm or less. Yes, the transmittance (T560) per 1 μm thickness at a wavelength of 560 nm is less than 40%, and the optical density based on the transmittance at a wavelength of 560 nm (OD560) and the optical density based on the transmittance at a wavelength of 950 nm (OD950) The ratio (OD950 / OD560) is 0.35 or less (hereinafter, “optical density based on transmittance” may be simply referred to as “optical density”).
In the present embodiment, the wavelength range of visible light is 380 nm or more and less than 800 nm based on the description of JIS-Z8120 “Short wavelength limit is 360 to 400 nm, Long wavelength limit is 760 to 830 nm”. In addition, light with a wavelength of 800 nm to 1 mm is infrared, and light with a wavelength of 800 nm to 2500 nm is near infrared. Furthermore, the “optical density” is represented by the above formula (1) when the transmittance T (%) is used. The “infrared transmitting black film” in the present embodiment means a film that transmits 3.0% or more of the infrared light.

In this embodiment, the transmittance (T ₅₆₀ ) at a wavelength of 560 nm is selected as an index indicating the transmittance, and the wavelength is in the middle of the visible light wavelength range, and is widely used as a wavelength representing visible light. This is because.
Here, the reason why T _{560 is set} to less than 40% is that when the visible light transmittance is less than 40%, the film can be regarded as black in appearance (viewed visually). That is, when the visible light transmittance of the member covering the light emitting unit and the light receiving unit of the remote controller is less than 40%, it becomes difficult to see the internal light emitting element and the light receiving element through the member, and the inside is shielded and concealed by the black film. This is because it can be regarded as a state. T ₅₆₀ is preferably 37% or less, and more preferably 35% or less. The lower limit of T ₅₆₀ is not particularly limited, but the detection limit of the measuring device is about 0.000001%.

In addition, if the ratio (OD ₉₅₀ / OD ₅₆₀ ) of the optical density (OD ₅₆₀ ) at a wavelength of ₅₆₀ nm to the optical density (OD ₉₅₀ ) at a wavelength of 950 nm is 0.35 or less, the wavelength of 950 nm frequently used particularly for a wireless remote controller. Necessary amount of transmitted light can be obtained for this light.
OD ₉₅₀ / OD ₅₆₀ is preferably 0.32 or less, and more preferably 0.30 or less. The lower limit of OD ₉₅₀ / OD ₅₆₀ is about 0.1.

Further, in the infrared transmission black film of the present embodiment, the OD _560, the ratio of the optical density (OD _NIR) at each wavelength in the following near infrared (NIR) wavelength region of wavelength 800nm 2500nm (OD _NIR / OD ₅₆₀ ) Is preferably 0.40 or less. If OD _NIR / OD ₅₆₀ is 0.40 or less, it has sufficient light intensity for various industrial near-infrared lasers, black matrix pattern alignment infrared rays, etc. while having a visible light shielding property. Therefore, it can be suitably used as an infrared transmitting black film.
OD _NIR / OD ₅₆₀ is more preferably 0.37 or less, and further preferably 0.35 or less. The lower limit of OD _NIR / OD ₅₆₀ is about 0.01.

In the infrared transmitting black film of this embodiment, the volume fraction of the black material is preferably 1.0% by volume or more and 25% by volume or less. By setting the volume fraction within this range, it is possible to secure a sufficient light shielding property in the visible light region when a black film is formed, and to obtain a high transmittance for light in the near infrared region or more. That is, when the volume fraction of the black material is less than 1.0% by volume, the black material is too small and there is a possibility that the light blocking property in the visible light region is insufficient. On the other hand, if the volume fraction of the black material exceeds 25% by volume, the infrared transmitting black film has a metallic luster, which may reduce the transmittance of light in the near infrared region or more, and the metallic luster. This is because the transmittance of light in the near-infrared region or more may be reduced because the amount of the black material is too large even when the light is not generated. The volume fraction of the black material is more preferably 2.0% by volume to 20% by volume, and even more preferably 2.0% by volume to 15% by volume.
In the black film of the present embodiment, the volume fraction of the black material is determined by calculating the volume of each component from the density of each component constituting the infrared transmitting black film and the weight of each component added when preparing the paint. It can be obtained by calculation.
In addition, since the resin component is volatilized by decomposition or oxidation at a relatively low temperature, the black material is stable up to a high temperature because it is a metal. The weight ratio between the resin component and the black material can be determined. On the other hand, the specific gravity of both the resin component and the black material can be determined by component analysis. From the specific gravity of each component, the volume fraction of the black material in the black film of this embodiment may be obtained.

(Black material)
As the black material in the present embodiment, metal fine particles mainly composed of silver and tin are suitably selected. Here, the above-mentioned “mainly composed of silver and tin” means that the metal fine particles contain at least both silver and tin components, and the total content of silver and tin is based on the whole metal fine particles. It means 50 mass% or more. That is, the components and contents are defined for the entire metal fine particles, and do not define the components and contents of the individual particles themselves.
Conventionally, it has been known that metal fine particles (nanometer-sized metal fine particles) having a particle diameter of about 1 nm to several hundreds of nm exhibit various color tones due to surface plasmon absorption of the metal. It is also known that the (wavelength) varies depending on the composition and particle diameter of the metal fine particles. In the present embodiment, by adjusting the composition and the particle diameter, it is only necessary to select metal fine particles that exhibit black in the visible light region and exhibit a certain level of transparency in the infrared region. Further, metal fine particles mainly composed of silver and tin can be selected.

As the metal fine particles mainly composed of silver and tin, silver-tin alloy fine particles, or mixed fine particles of silver-tin alloy fine particles and silver fine particles can be suitably used.
Here, when the metal fine particles mainly composed of silver and tin are silver tin alloy fine particles, the content of the silver component in the silver tin alloy fine particles, that is, the ratio of the silver component to the total amount of silver and tin (silver / (Silver + tin): mass%) is preferably 45 mass% or more and 95 mass% or less, more preferably 50 mass% or more and 95 mass% or less, and further preferably 60 mass% or more and 92 mass% or less. It is.
Further, when the metal fine particles mainly composed of silver and tin are mixed fine particles of silver tin alloy fine particles and silver fine particles, the content of silver component in the mixed fine particles of the silver tin alloy fine particles and silver fine particles, that is, silver and tin The ratio of the silver component to the total amount (silver / (silver + tin): mass%) is preferably 45 mass% or more and 95 mass% or less, more preferably 50 mass% or more and 95 mass% or less, More preferably, it is 60 mass% or more and 92 mass% or less.
The reason why the content of the silver component is limited to the above range is that when the ratio of the silver component is 45% by mass or more and 95% by mass or less, the reflectance of visible light is not increased and the black has sufficient blackness. This is because a film can be obtained and sufficient light shielding properties can be obtained, and the black film also has infrared transmittance.
The preferable content range of the silver component is a preferable content range of the silver component in the entire fine particles when a certain amount of the silver tin alloy fine particles or a mixed fine particle of the silver tin alloy fine particles and silver fine particles is taken. This does not indicate a preferable content range of the silver component in each particle.

In addition, the average dispersed particle size in the black film of the black material in the present embodiment may be 1 nm or more and 100 nm or less, preferably 2 nm or more and 80 nm or less, and more preferably 5 nm or more and 50 nm or less. If the average dispersed particle size in the film is 100 nm or less, Rayleigh scattering and Mie scattering in the infrared region due to the presence of fine particles of black material can be suppressed, and reduction in infrared transmittance can be suppressed. .
That is, as described above, the black material in the present embodiment has light transmittance in the infrared region, but the average primary particle diameter of the metal fine particles dispersed in the resin as in the prior art is in the range of 1 nm to 200 nm. By simply doing, Rayleigh scattering and Mie scattering occurring in the infrared region cannot be suppressed, and as a result, sufficient infrared transmission characteristics cannot be obtained. However, by suppressing the Rayleigh scattering and Mie scattering by setting the average dispersed particle size in the black film to 100 nm or less as in the present embodiment, sufficient transmission characteristics can be obtained even in the infrared region.
In addition, in order to prevent the influence of Rayleigh scattering or Mie scattering of visible light in the optical element, the average dispersed particle diameter of dispersed fine particles is preferably 20 nm or less. However, since Rayleigh scattering and Mie scattering have wavelength dependency based on the generation mechanism, the allowable particle diameter is increased in the case of infrared rays having a longer wavelength than visible light. Infrared transmissivity does not require as high transmissivity as an optical element and allows some scattering, so that the average dispersed particle size can be increased to 100 nm.

  On the other hand, the average dispersed particle size of the black material in the present embodiment is 1 nm or more. The reason is that when the average particle diameter is less than 1 nm, the crystallinity of the particles is lowered, so that the absorption state of visible light becomes unstable and sufficient blackness may not be obtained.

  The average dispersed particle size of the black material in the infrared transmitting black film in the present embodiment is obtained by cutting the obtained infrared transmitting black film into a thin piece in the cross-sectional direction using FIB (focused ion beam) or the like, and using a transmission electron microscope. It can be determined by observing the particles of black material in the flakes using (TEM). That is, a specific number (usually several tens or more) of particles are randomly selected from the TEM photograph, the particle diameter thereof is measured, and the average value thereof is set as the average dispersed particle diameter. In addition, since the particle | grains of this embodiment are substantially spherical shape, what is necessary is just to let the largest diameter of each particle | grain be the particle diameter of this particle | grain.

In the present embodiment, the silver-tin alloy fine particles may include not only those that can be clearly determined as a silver-tin alloy by having a crystal structure of silver-tin alloy, but also those that have a crystal structure of silver.
First, as an example of a silver-tin alloy having a crystal structure, the range of X when the silver-tin alloy is represented by the chemical formula Ag _{1 -X} Sn _X (X is a real number) is 0.118 ≦ X ≦ 0.2285. Ζ phase and 0.237 ≦ X ≦ 0.25 ε phase are known (according to Binary Alloy Phase Diagram, p. 94-97). Moreover, as for what has a crystal structure of silver, in the state which maintained the structure of silver crystal, it becomes what substituted a part of silver atom in silver crystal by the tin atom, but in the said literature, as (Ag) phase, As shown, when the silver-tin alloy having this silver crystal structure is represented by the chemical formula Ag _1-Y Sn _Y (Y is a real number), Y is considered to satisfy 0 <Y ≦ 0.115.
In the above, Y = 0 (Ag ₁ Sn ₀ ) corresponds to a silver single phase, that is, silver fine particles, and thus is excluded from the range of Y defined as silver tin alloy fine particles. However, since the silver and tin-based metal fine particles suitably used as the black material are preferably silver tin alloy fine particles or mixed fine particles of silver tin alloy fine particles and silver fine particles, May include Y = 0.

  Further, the black material composed of the silver-tin alloy fine particles or the mixed fine particles of the silver-tin alloy fine particles and the silver fine particles does not substantially contain the tin fine particles. Here, being substantially free of tin fine particles means that the presence of a substance having a tin crystal structure is not confirmed by X-ray diffraction. When this black material contains tin fine particles, the light shielding property of the black light-shielding film formed using the black material is significantly lowered.

The production method of the black material in the present embodiment is not particularly limited as long as the above composition and particle diameter can be obtained. Gas phase reaction method, spray pyrolysis method, liquid phase reaction method, freeze drying method, water Metal fine particle synthesis methods such as thermal synthesis can be applied, but these fine particles are particularly easy when silver tin alloy fine particles or mixed fine particles of silver tin alloy fine particles and silver fine particles are selected as the black material. It is preferable to use the liquid phase reaction method obtained in (1).
As the liquid phase reaction method, it is preferable to use an aqueous reaction system. For example, a method of dropping a silver compound solution into a tin colloid dispersion and alloying tin and silver, or silver colloid and tin colloid By adding an oxidizing agent or a reducing agent to the dispersion in which silver coexists, silver tin alloy fine particles and silver fine particles can be generated using a method of alloying silver and tin. With this production method, the reaction conditions (for example, the ratio of tin and silver (silver ions), the pH of the reaction solution, the reaction temperature, the reaction time, the type and amount of the oxidizing agent and reducing agent, etc.) should be adjusted appropriately. The amount of silver tin alloy fine particles produced, the amount of silver fine particles produced (including the case where substantially no silver tin alloy fine particles are produced), and the amount of silver tin alloy fine particles and silver fine particles produced The ratio can be arbitrarily controlled.

  Further, in order to uniformly disperse the black material in the resin component or to increase the affinity between the black material and the resin component, it is preferable to treat the surface of the black material with a surface treatment agent or a dispersant. . These surface treatment agents and dispersants may be selected from known materials in accordance with the material of the resin component and the method of dispersing the black material in the resin component. The infrared transmitting black film of the present embodiment can be obtained by adjusting the dispersion method and dispersion conditions together with the type of the dispersant and by dispersing the black material in the resin component.

As the dispersant, a polymer dispersant is preferable. For example, urethane dispersant, modified polyester dispersant, polycarboxylate, polyalkyl sulfate, polyvinyl pyrrolidone (PVP), polyvinyl alcohol (PVA), polyacrylamide. Etc.
In addition, when a resin component raw material is cured from a black paint to be described later to form an infrared transmitting black film, the polymer dispersant having a preferable structure for maintaining the dispersibility of the black material includes a random copolymer, a comb type A copolymer, an ABA type copolymer, a BAB type copolymer, a polymer having a hydrophilic group at both ends, a polymer having a hydrophilic group at one end, and the like can be selected. Among these, the black component in the resin component raw material and the solvent highly compatible with the resin component raw material described later, in other words, the resin component, the resin component raw material, and the black material in the solvent highly compatible with the resin component raw material. In view of the high dispersibility, random copolymers and comb copolymers are preferred.
Specific examples of the dispersant include EFKA (manufactured by EFKA Chemicals Beebuy (EFKA)), Disperbyk (manufactured by Big Chemie), Disparon (manufactured by Enomoto Kasei Co., Ltd.), SOLPERSE (manufactured by Geneka), and KP (manufactured by Shin-Etsu Chemical). ) And polyflow (manufactured by Kyoeisha Chemical Co., Ltd.).

  Examples of the surface treatment agent include coupling agents such as a silane coupling agent and a titanium coupling agent.

  This black material has a high blackness and an excellent light-shielding property for visible light and has infrared transmission properties due to the characteristics of the material itself. And the scattering of the infrared rays resulting from particle | grains is also suppressed by controlling the dispersion | distribution particle diameter. Furthermore, since it is composed of an inorganic material, it has high chemical stability, and there is no concern about fading even when exposed to sunlight or ultraviolet rays such as a fluorescent lamp.

(Resin component)
As the resin component, any inorganic resin or organic resin may be used as long as the black material is dispersible and does not have strong absorption in the infrared wavelength region to be used. However, organic resins such as acrylic resins, epoxy resins, polyester resins, and polyurethane resins, and liquid crystal and MEMS resist compounds can be preferably used. In addition, filler materials made of inorganic substances for improving the hardness of the film or adjusting the refractive index of the film, additives for improving the adhesion to the coating substrate, etc. may be added. .

  The acrylic resin is selected from, for example, polymers based on one or more monomers, oligomers, and prepolymers selected from acrylic resin monomers, oligomers, and prepolymers described in the resin component raw materials described later. Examples of polymers include polymethyl (meth) acrylate, polycyclohexyl (meth) acrylate, polyethylene glycol di (meth) acrylate, poly-trimethylolpropane tri (meth) acrylate, and poly-pentaerythritol tetra Examples thereof include poly (meth) acrylic acid ester resins such as (meth) acrylate. Here, “(meth) acrylate” means “acrylate or methacrylate”. The same applies hereinafter.

  Epoxy resins include glycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, polyglycerol diglycidyl ether, phenol novolac epoxy resin, cresol novolac epoxy resin, bisphenol epoxy resin, trisphenol. Normethane type epoxy resin, glycidyl (meth) acrylate and styrene copolymer epoxy resin, glycidyl (meth) acrylate, styrene and methyl (meth) acrylate copolymer epoxy resin, glycidyl (meth) acrylate and cyclohexylmaleimide copolymer A polymer epoxy resin, a fluorene-type epoxy resin, etc. can be mentioned.

  The polyester resin is not limited as long as it is commonly used in paints. For example, polyvalent carboxylic acids such as adipic acid, sebacic acid, and isophthalic acid, and polyhydric alcohols such as ethylene glycol and trimethylolpropane. And the like. Further, the polyurethane resin is not limited as long as it is generally used in paints. For example, a polyurethane resin obtained by reacting an isocyanate group with a polyol to extend a chain is preferable. Examples of the polyol include polyester polyol, polyether polyol, and acrylic polyol.

(Other ingredients)
The infrared transmitting black film of this embodiment may contain various components such as a filler material in addition to the black material and the resin component.
The filler material can be added for the purpose of improving the hardness of the infrared transmitting black film or adjusting the refractive index. As the filler material, an inorganic substance, particularly an inorganic oxide, is stable and preferable. Since the dispersed particle size of the filler material needs not to cause infrared scattering, the average dispersed particle size in the black film is preferably 50 nm or less.

As the filler material for improving the hardness of the infrared transmitting black film, an inorganic oxide having a refractive index comparable to that of the resin component is preferable. From the viewpoint of availability and price, silica (silicon dioxide) fine particles are used. Preferably used.
For the purpose of adjusting the refractive index, for the purpose of increasing the refractive index, for example, fine particles made of a high refractive index material such as zirconia or titania may be used. For example, fine particles having a low refractive index having fine voids such as nanoporous silica and hollow silica may be used.

  In addition, the silver tin alloy fine particles used as the black material and the fine particles composed of the silver fine particles used in the infrared transmitting black film of the present embodiment have a blackness level as compared with carbon black and titanium black used as the black material in the conventional black film. Therefore, as described above, the content in the film can be reduced to a range of 1.0 volume% or more and 25 volume% or less. For this reason, even if a substance other than the black material is added, the film formability and the characteristics of the film itself can be maintained, so that such a filler material can be added.

[Infrared transmitting black film manufacturing method]
The infrared transmission black film of this embodiment can be obtained as follows, for example.
First, a black material is prepared.
As the black material, the above-mentioned metal fine particles mainly composed of silver and tin are suitable, and in particular, fine particles composed of silver-tin alloy fine particles and silver fine particles can be more suitably used. And also about the manufacturing method, it is preferable to use the above liquid phase reaction methods, for example.
Here, the black material is a fine particle having a hydrophilic surface, as can be seen from the fact that the metal is a main component and is preferably manufactured by a liquid phase reaction method of an aqueous reaction system. Therefore, in order to uniformly mix such a black material into the resin component raw material, it is necessary to form a form that can be directly dispersed in the resin component raw material or to disperse the black material in a solvent that is highly compatible with the resin component raw material. For this purpose, it is preferable to perform a surface treatment with a polymer dispersant or a surface treatment agent. In the following description, the polymer dispersant and the surface treatment agent may be collectively referred to as “polymer dispersant or the like”. The resin component raw material will be described later.

In the surface treatment, the amount of the polymer dispersant or the like that binds to the black material surface is preferably in the range of 5 to 30% by mass with respect to the black material. Further, there are more suitable ranges depending on the composition of the black material, the primary particle diameter, and the composition of the resin component raw material described later in which the black material is dispersed and mixed. The reason for this is that in the case of forming a coating film from a black paint formed using this black material and further forming an infrared transmitting black film, the dispersibility of the black material in the coating film or in the infrared transmitting black film is reduced. This is because, in order to ensure, it is necessary to strictly adjust the amount of the polymer dispersant or the like added to the black material.
That is, when the amount of the polymer dispersant or the like is small, a part of the black material particle surface with a small coating amount of the polymer dispersant or the like is formed, and the affinity for the resin component raw material or the solvent in the part is formed. The black material particles are agglomerated from the portion where the coating amount of the polymer dispersant or the like is small after the black material is dispersed in the resin component raw material or the solvent. There is a risk that.

  On the other hand, when the amount of the polymer dispersant or the like is excessive, the dispersant itself may be a factor for reducing the dispersibility. Furthermore, when the infrared ray transmitting black film is formed by curing the resin component raw material, excessive polymer dispersant or the like may hinder the curing due to polymerization of the resin component raw material, and sufficient film strength may not be obtained. is there. In addition, when a photoresist or the like is used for the cured resin, developability may be deteriorated in a development process after exposure with light.

As described above, in order to strictly adjust the amount of the polymer dispersant or the like added to the black material, the polymer dispersant or the like is added to the aqueous solvent in which the black material particles having a hydrophilic surface are dispersed, and the like is stirred. It is preferable to dry the black material particles using a method of removing only the solvent, for example, an evaporator, after coating the surface of the black material particles with a polymer dispersant. In this way, a design amount of the polymer dispersant can be used for the black material particles.
Furthermore, even if the treatment of the dispersant is not uniform at the time of the surface treatment with the polymer dispersant or the like, the surface-treated black material particles are dispersed in the resin component raw material or a solvent highly compatible with the resin component raw material. After that, because the adsorption and desorption equilibrium of the polymer dispersant etc. with respect to the black material particles can be made uniform, the coating of the polymer dispersant etc. with respect to each particle can be made uniform, so that the uniform dispersibility of the black material is ensured. become.

On the other hand, in this surface treatment, it is not preferable to use a dispersion treatment method that has been generally performed.
That is, in the conventional dispersant treatment method, the polymer dispersant is added to the surface of the black material particles by adding the polymer dispersant to the aqueous solvent in which the black material particles having a hydrophilic surface are dispersed and stirring. After the coating treatment, the black material particles coagulated and settled by the coating treatment are separated from the solvent by filtration, centrifugation, or the like, and dried to perform surface treatment with the polymer dispersant. Alternatively, solvent replacement is performed by extracting and dispersing particles coated with the polymer dispersant as described above in an aqueous or polar solvent directly in a non-aqueous solvent. However, in these methods, since a part of the polymer dispersant or the like remains in the separated aqueous solution, the coating amount of the polymer dispersant or the like becomes smaller than the designed amount. For this reason, problems such as aggregation of the black material particles as described above may occur.

  Furthermore, since it is difficult to estimate the amount of the polymer dispersant remaining in the solution, it is difficult to add an excessive amount of polymer dispersant etc. corresponding to the residual amount. When the amount is insufficient, the problem is not solved. On the other hand, when the amount is excessive, the amount of the polymer dispersant and the like becomes excessive, which may cause problems such as inhibition of curing of the resin component raw material.

Moreover, it is preferable that the moisture content in the black material surface-treated with the obtained polymer dispersing agent etc. is 2.0 mass% or less with respect to a process particle. This is to prevent aggregation of black material particles, whitening of the resin, and the like when forming a coating film from a black paint, which will be described later, and further curing the resin component raw material to form an infrared transmitting black film.
In other words, if the coating film contains both a solvent and moisture that are highly compatible with the resin component raw material, the solvent will be removed by drying, and the amount of water will be relatively increased. When the value exceeds a certain value, the dissolution parameter in the coating film changes greatly, which may cause a phenomenon such as aggregation of particles or whitening of the resin. In order to prevent this problem, it is necessary to keep the water content of the black paint as small as possible, and at the time of surface treatment with a polymer dispersant or the like where water is most likely to be mixed, the water content of the black material should be as small as possible. It is because it is preferable to leave.

As a method of reducing the water content of the black material subjected to the surface treatment with such a polymer dispersant, a method of removing only the solvent, for example, a method of drying the black material particles using an evaporator or the like. It can be used suitably.
On the other hand, for example, there is a method of removing moisture by heating the black material subjected to the surface treatment for a long time using a dryer of 150 ° C. or higher, but in this case, the low molecular dispersant volatilizes or decomposes. That is, it is not preferable because it causes a change in the processing amount or alteration of the dispersant.

Next, a black paint containing a black material surface-treated with a polymer dispersant or the like and a resin component raw material is prepared. Here, the resin component raw material is in a liquid state and forms the resin component by curing, solvent distillation or the like, and in addition to the resin component monomer, oligomer, prepolymer, the resin component is dissolved in the solvent. In addition, a resin component monomer, oligomer, or prepolymer dissolved in a solvent is also included.
When the resin component monomer, oligomer, or prepolymer is in a liquid state, the resin component monomer, oligomer, or prepolymer is used as a raw material for the resin component, and a black material is mixed and dispersed therein to produce a black paint. Good. Also, a solution in which a resin component or solid resin component monomer, oligomer, or prepolymer is dissolved in an appropriate solvent to form a liquid, or a solution in which a liquid resin component monomer, oligomer, or prepolymer is diluted in a solvent. As a resin component raw material, a black material may be mixed and dispersed therein to produce a black paint.
Further, the black paint may contain the filler material and additives described later.

  In this embodiment, the black material surface-treated with the polymer dispersant or the like may be mixed and dispersed in the resin component raw material in the form of fine particles to form a black paint. A black paint may be formed by preparing a black material dispersion in which a black material is dispersed in a highly soluble solvent, and mixing the dispersion and the resin component raw material. In addition, in the black material dispersion, the filler material may be dispersed in advance, or an additive described later may be dissolved.

The average dispersed particle size of the black material in the black paint or the black material dispersion is preferably 100 nm or less, more preferably 50 nm or less. By setting the average dispersed particle size in the black paint or black material dispersion to 100 nm or less, the average dispersed particle size of the black material in the infrared transmitting black film produced using this paint or dispersion is suppressed to 100 nm or less. As a result, it is possible to suppress a reduction in infrared transmittance based on the occurrence of Rayleigh scattering and Mie scattering in the infrared region.
The average dispersed particle size is measured for the prepared black paint and the like using a particle size distribution measuring apparatus (for example, Microtrac 9340-UPA, manufactured by Nikkiso Co., Ltd.) using a dynamic light scattering method. A value of 50% by number from the small particle size side of the number distribution can be obtained as the average dispersed particle size.

As the resin component raw material, monomers, oligomers and prepolymers of the resin component can be suitably used.
Examples of acrylic resin monomers include methyl (meth) acrylate, cyclohexyl (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di ( (Meth) acrylates such as (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and glycerol (meth) acrylate Acrylic esters; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate Monomers containing a hydroxyl group and the like; and polyester compounds containing these, urethane compounds, bisphenol-based (meth) acrylate compounds, and fluorene-based (meth) acrylate compounds, and the like. In addition, oligomers and prepolymers include polymethyl (meth) acrylate, polycyclohexyl (meth) acrylate, polyethylene glycol di (meth) acrylate, poly-trimethylolpropane tri (meth) acrylate, and poly-pentaerythritol tetra (meth). Examples include poly (meth) acrylic acid ester resins such as acrylate.
As other acrylic resin, for example, a baking type acrylic resin such as “Acridick” series manufactured by DIC Corporation may be used.

  Epoxy resin monomers, oligomers and prepolymers include glycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, polyglycerol diglycidyl ether, phenol novolac epoxy resin, cresol novolac epoxy resin, bisphenol. Type epoxy resin, fluorene type epoxy resin, trishenol methane type epoxy resin, copolymer epoxy resin of glycidyl (meth) acrylate and styrene, copolymer epoxy resin of glycidyl (meth) acrylate, styrene and methyl (meth) acrylate , Glycidyl (meth) acrylate and cyclohexylmaleimide copolymer epoxy resin and other prepolymers before cross-linking network It is possible.

In this embodiment, the resin component raw material has ultraviolet photosensitivity, and as will be described later, the coated and dried film is exposed and developed to form a black film with a complicated design and improved design. It is preferable in that it can be performed. Moreover, it can also be used as a black resist for black pattern formation by using the resin component raw material which has ultraviolet photosensitivity.
Here, the ultraviolet photosensitivity includes a negative type (the photosensitive part remains by development) and a positive type (the photosensitive part is removed by development), but the negative type is preferable. The reason is that this infrared transmitting black film or black film material has a light-shielding property against ultraviolet rays, so that the bottom of the film is not sufficiently exposed even in the exposed part (ultraviolet irradiation part). This is because a negative film is more preferable in order to prevent this effect because a residual film is likely to be generated.

As the resin component raw material having ultraviolet sensitivity, a commercially available resist material can be used, and a photoreactive agent is added to the acrylic resin, epoxy resin, polyester resin, and polyurethane resin. Also good. As the commercially available resist material, those for liquid crystal or MEMS are preferably used. The reason for this is that a permanent film is obtained by performing a treatment such as thermosetting on a film formed of these resist materials. This is because it becomes possible to form.
As the commercially available resist compound, for example, “Lipoxy” PR series and SPC series manufactured by Showa Polymer Co., Ltd., “ZCR1569H” manufactured by Nippon Kayaku Co., Ltd., and the like can be used. Further, it is more preferable if a resist component (excluding pigment) of a pigment dispersion resist commercially available for forming a liquid crystal black matrix or a color filter can be used.

Moreover, you may add the reaction initiator for hardening these resin component raw materials to a black coating material. The reaction initiator may be any substance that initiates / accelerates polymerization of the resin component by generating radicals by heat or light, but examples of the photoreaction initiator include Darocur Series from Ciba Specialty Chemicals. (For example, 1173) and Irgacure series (for example, 651, 184, 908, 2959, OXE01, OXE02, etc.) and the like may be used, and these may be used alone or in combination of two or more.
Thus, by giving photocurability to the resin component raw material, the resin component raw material can be handled as a negative resist.

The solvent used for the resin component raw material and the solvent used for the black material dispersion are not particularly limited as long as the solubility of the resin component (raw material) used and the dispersibility of the black material can be maintained. For example, methanol, ethanol, ethylene glycol monomethyl ether, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol monoethyl ether, propylene glycol monomethyl ether acetate, methyl ethyl ketone, and methyl isobutyl A ketone etc. can be mentioned.
In addition, it is natural that the resin component raw material and the solvent used in the black material dispersion have sufficient compatibility, but when the resin component raw material contains a solvent, the solvent and the solvent in the black material dispersion In the meantime, sufficient compatibility is required. When the compatibility is insufficient, the black material may be agglomerated or settled, or the paint may be disproportionated when both are mixed to produce a black paint.

Mixing and dispersion for obtaining the black paint or black material dispersion is a known dispersion such as an ultrasonic dispersion machine, paint shaker, ball mill, bead mill, Eiger mill, etc. It can be carried out by setting a dispersion condition such that an average dispersed particle size of the black material can be obtained using a machine, and carrying out a dispersion treatment.
Furthermore, when mixing the black material, in addition to the addition of a solvent for adjusting the viscosity and dispersion state, the addition of the filler material and the curing agent, the addition of a low molecular weight crosslinking agent for improving the hardness of the film, A silane coupling agent or the like for improving the adhesion between the infrared transmitting black film to be formed and the coated substrate may be added within a range that does not deteriorate the characteristics of the infrared transmitting black film to be formed.

The black paint thus obtained is applied onto a substrate to form a coating film.
The substrate to be used may be selected according to the method of use and form of use of the infrared transmitting black film, and is not particularly limited. For example, in addition to an inorganic substrate such as glass, the substrate has a high hardness such as an acrylic substrate and a polycarbonate substrate. If a substrate is used, a structure having an infrared transmitting black film can be obtained. Moreover, if a polymer film such as PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PES (polyethylene sulfone), or TAC (triacetylcellulose) is used, a flexible infrared transmitting black film can be obtained. It can also be obtained.

  The coating method (coating film forming method) of the black paint is not particularly limited, but spin coating, flow coating, spray coating, dip coating, die coating, gravure coating, knife coating, Examples thereof include a bar coating method and an ink jet method.

An infrared transmitting black film can be obtained by curing the obtained coating film or removing the solvent by volatilization. In addition, when obtaining a black film by the above-described curing, if a solvent is included in the black paint, the solvent in the coating film is first removed to form a coating dry film (a solid film is formed by removing the solvent). However, the polymerization and curing of the resin component hardly occur, and the coating film is cured after forming a film in a state where it can be dissolved in the solvent again by contacting with the solvent.
As a curing method, the monomer, oligomer, and prepolymer of the resin component raw material may be heated at a temperature at which thermal polymerization starts, and when a reaction initiator is added, heat or light corresponding to the reaction initiator is added. Application may be performed. Moreover, you may use both together.

Next, a process for obtaining a complicated shape by performing ultraviolet irradiation (exposure) and development on a coating film using a black paint containing a resin component material having ultraviolet sensitivity will be briefly described.
There is no particular limitation on the exposure method, but exposure can be easily performed by using a commercially available ultraviolet exposure device and a photomask as long as it has a planar shape. In addition, so-called direct drawing (direct drawing) can be performed in which an ultraviolet laser is used as the light source and a fine laser beam is scanned to directly write a pattern on the coated and dried film.
There is no particular limitation on the developing method, and a normal method such as a dip method or a paddle method may be used. These exposure and development conditions may be appropriately selected and adjusted according to the resin component raw material to be used and the required shape.
According to the above process, for example, a resist material is used as a resin component raw material, and a complex shape is obtained by exposing and developing a coated dry film to obtain a black matrix described later.

[Substrate with film having infrared transmitting black film]
As described above, since the infrared transmissive black film of the present embodiment is formed on a suitable substrate, by forming the infrared transmissive black film on the substrate, the substrate with a film having the infrared transmissive black film is formed. Can be obtained.
As the base material, the substrates mentioned in the above-described formation of the black film can be similarly used. Examples of the shape include a flat plate, a film shape, and a sheet shape. By molding this base material into a required shape in advance or by molding the obtained base material with a film having an infrared transmitting black film, a product such as a signal cover such as a wireless remote controller can be obtained. Can do. A black matrix can be obtained by forming a black film with a matrix pattern on the substrate. In addition, all of the substrates with the infrared transmitting black film of the present embodiment formed on the substrate are included in the substrate with a film of the present embodiment regardless of the shape of the substrate and the form of the black film.

[Image display device]
The infrared transmitting black film of the present embodiment can be suitably used as a component constituting a display element or the like in the image forming apparatus. That is, the image display device of the present embodiment only needs to have the black film of the present embodiment in the device, and the aspect may include the substrate with the film of the present embodiment in the device. However, it may be other than that. Examples of the image forming apparatus include a plasma display display apparatus, an EL display apparatus, a CRT display apparatus, a liquid crystal display apparatus, and the like. Especially, when used in a liquid crystal display apparatus or an EL display apparatus, the effect of the black film of the present embodiment is achieved. Prominently demonstrated.

For example, by using a resin-forming component having ultraviolet sensitivity as described above, it is possible to use a black paint as a pigment dispersion resist (black resist) for forming a liquid crystal black matrix or a color filter. And the infrared rays transmission black film of this embodiment formed by this can be used as a black matrix for image display apparatuses, such as a liquid crystal, and a color filter.
That is, after forming a coating and drying film using the black paint on a black matrix substrate, a black matrix pattern is formed by exposure and development, and the black matrix pattern is cured by thermosetting to form a permanent film. For example, a black matrix using the infrared transmitting black film of this embodiment can be produced. Furthermore, a color filter can be produced by combining this black matrix pattern and a color filter element / pattern.

  Here, in the above-described COA type or BOA type black matrix, it is necessary to directly align the array and the black matrix pattern. However, the black film of this embodiment has infrared transparency, and further, In principle, the coated and dried film also has infrared transparency, so that an alignment signal using infrared rays having a wavelength range of 850 to 950 nm can be easily read. Therefore, a COA type or BOA type black matrix can be easily produced.

  In addition to the color filter, the image display device of this embodiment includes an electrode substrate, a polarizing film, a retardation film, a backlight, a spacer, and the like. Although generally composed of various members such as a viewing angle compensation film, an antireflection film, a light diffusion film, and an antiglare film, the black film of the present embodiment can be applied to these members and the like as necessary.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.
<Measurement and evaluation methods>
Below, each measurement or evaluation method, such as the characteristic of a material and a sheet | seat employ | adopted in the Example or the comparative example, is shown.

(Content of silver component in black material)
The content ratio of the silver component in the black material (silver tin alloy fine particles or a mixed fine particle of the silver tin alloy fine particles and silver fine particles) is determined by using a green compact powder compact as an electron beam microanalyzer (EPMA, JEOL Ltd., JXA8800 ) And by measuring the content ratio (mass ratio) of tin and silver in the powder by qualitative and quantitative analysis.

(Moisture content and amount of polymer dispersant in black powder surface-treated with polymer dispersant)
The amount of water and the amount of the polymer dispersant of the black powder made of a black material which was surface-treated with a polymer dispersant and dried were measured using TG-DTA (TG-8210, manufactured by Rigaku Corporation). From the DTA results, it is assumed that the weight loss from room temperature to 120 ° C depends on the evaporation of water, and the weight loss from 140 ° C to 500 ° C depends on the thermal decomposition of the polymer dispersant. The amount was regarded as the amount of water and the amount of polymer dispersant.

(Optical density in the visible light region of the black film)
The optical density (OD value: Optical Density) in the visible light region of the infrared light transmitting black film was measured using a transmittance densitometer (manufactured by TECHKON: RT-120) for a glass substrate with a black film. By using the measured value (without film) as a reference value, the OD value of the infrared transmitting black film itself was obtained.

(Transmittance of black film and optical density ratio for each wavelength)
The transmittance of the infrared transmitting black film is measured with respect to a glass substrate with an infrared transmitting black film by using a spectrophotometer to measure the spectral transmittance of 370 to 2500 nm, and the infrared transmission using the glass substrate alone (without film) as a reference value. The light transmittance at each wavelength of the black film was determined. In addition, the said spectrophotometer is based on the measurement wavelength and the measurement light quantity, U-4100 (measurement wavelength range: 200-2500 nm, detection limit: 0.001%) made by Hitachi, Ltd., MCPC-3700 (made by Otsuka Electronics Co., Ltd.) Measurement wavelength range: 300 to 1000 nm, detection limit: 0.000001%) were used in combination.
On the other hand, the optical density ratio for each wavelength is as follows: transmittance (T ₅₆₀ ) at a wavelength of ₅₆₀ nm, transmittance (T ₈₀₀ ) at a wavelength of ₈₀₀ nm, transmittance (T ₉₅₀ ) at a wavelength of ₉₅₀ nm, and transmission at a wavelength of 1064 nm. From the values of the transmittance (T ₁₀₆₄ ), the transmittance at a wavelength of 1500 nm (T ₁₅₀₀ ), the transmittance at a wavelength of 2000 nm (T ₂₀₀₀ ), the transmittance at a wavelength of 2500 nm (T ₂₅₀₀ ), and the transmittance at each wavelength, the following formula (1 ) To calculate the optical density (OD value), and the ratio (OD _NIR / OD ₅₆₀ ) of the OD value at each wavelength from 800 nm to 2500 nm (NIR) and the OD value at a wavelength of 560 nm was determined.
OD = −log (T / 100) (1)

(Average dispersed particle size in black film of black material)
The average dispersed particle size in the black film of the black material was obtained by cutting the obtained infrared transmission black film into a thin piece in the cross-sectional direction using FIB, and using a transmission electron microscope (TEM, JEOL Ltd., JEM-2100F). Then, the particle shape of the black material of the cross section of the film was observed, 50 particles were randomly selected from the TEM photograph, the particle diameter (maximum diameter) was measured, and the average value was defined as the average dispersed particle diameter.
In addition, since the particle | grains of this embodiment are substantially spherical, there is no problem even if it makes the maximum diameter of each particle | grain the particle diameter of this particle | grain.

<Example 1>
(Formation of black film)
In 200 ml of pure water kept at 60 ° C., 15.0 g of a tin (Sn) colloid dispersion (average primary particle size: 20 nm, solid content: 20% by mass, manufactured by Sumitomo Osaka Cement Co., Ltd.) and silver (Ag) colloid ( Average particle diameter: 7 nm, solid content: 20% by mass, manufactured by Sumitomo Osaka Cement Co., Ltd. 60.0 g and 0.75% by mass polyvinylpyrrolidone (PVP, manufactured by Tokyo Chemical Industry Co., Ltd., trade name: K15) aqueous solution 100 g were added, A colloidal solution was obtained.
Next, while stirring this colloidal solution, 75 g of 0.05 mol / l nitric acid aqueous solution was slowly added dropwise thereto, and 450.0 g of 10.0% by mass citric acid aqueous solution was further added to prepare a mixed solution.

  Next, this mixed liquid was reacted by stirring for 10 hours at 60 ° C. using a magnetic stirrer, and then washed and concentrated by centrifugation to obtain a colloid liquid A having a black particle concentration of 15.0 mass%. It was. Thereafter, 7.5 g of a comb urethane polymer dispersing agent (manufactured by Big Chemie, trade name: Disper Byk161, nonvolatile content: 30% by mass) is added to 100.0 g of the colloid liquid A, and then the solvent is removed by an evaporator. And it was made to dry and the black powder A was obtained. As a result of measuring the water content and the polymer dispersant amount of the obtained black powder A by the above-described method, the water content was 1.5% by mass and the polymer dispersant amount was 13.05% by mass.

When the product phase in this black powder A was identified by the powder X-ray diffraction method, the presence of tin was not confirmed, but the silver-tin alloy phase (Ag ₃ Sn and / or Ag ₄ Sn structure), the silver phase (Ag structure) The existence of was confirmed. In the silver-tin alloy phase, the X-ray diffraction patterns of Ag ₃ Sn and Ag ₄ Sn are approximate, so which of the two components is generated or whether both components are generated Identification has not been made. Moreover, a silver phase shows the phase which has a silver crystal structure, Comprising: It is not limited to 100% of silver components, There exists a possibility that the tin has dissolved.
Further, the green powder A green compact was analyzed with an electron beam microanalyzer (EPMA), and the content ratio of tin and silver (silver / (silver + tin): mass ratio) was determined to be silver / (silver + Tin) = 91.3%.

Black dispersion A was obtained by adding 82.75 g of propylene glycol monomethyl ether acetate to 17.25 g of the obtained black powder A and irradiating ultrasonic waves for 20 minutes. To this black dispersion A: 50 g, an acrylic resin solution (KAYARAD ZCR-1569H, manufactured by Nippon Kayaku Co., Ltd., nonvolatile content: 70% by mass) 8.78 g and dipentaerythritol hexaacrylate 1.54 g are added as a resin component raw material. Further, 0.61 g of propylene glycol monomethyl ether acetate was added, followed by treatment with an ultrasonic disperser for 5 minutes, and left for 1 hour to obtain a black paint A.
The average dispersed particle size of the black material in the black paint A was measured and found to be 22 nm.

The black paint A was applied on a non-alkali glass substrate having a thickness of 0.7 mm by a spin coating method to form a black coating film. Here, the thickness of the coating film was controlled by adjusting the rotational speed of the spin coat so that the thickness of the infrared transmitting black film after heat curing was 1.0 μm.
Next, the glass substrate on which the coating film was formed was heated in the atmosphere at 230 ° C. for 1 hour using a heating device to obtain a glass substrate with an infrared transmitting black film A-1.

(Evaluation of black film)
-Evaluation of optical properties-
Using the glass substrate with the infrared transmitting black film A-1 obtained as described above, the optical density in the visible light region (OD value: Optical Density), and the wavelengths of 560 nm, 800 nm, 950 nm, 1064 nm, and 1500 nm by the above-described method. Each transmittance (T (%)) at 2000 nm and 2500 nm was measured. The optical density (OD) was determined from these transmittances. The results are summarized in Tables 1 and 2.
Further, Table 3 shows values of the ratio (OD _NIR / OD ₅₆₀ ) of the optical density (OD _NIR ) at each wavelength from 800 nm to 2500 nm and the optical density (OD ₅₆₀ ) at the wavelength of 560 nm.

-Average dispersed particle size in black film of black material-
For the infrared transmitting black film A-1, the particle shape of the black material in the film was observed with a transmission electron microscope (TEM) according to the above-described method. A TEM observation photograph of the film cross section is shown in FIG. Further, from this TEM photograph, the particle diameter of the dispersed particles was measured to obtain the average dispersed particle diameter. The results are also shown in Table 3. In addition, the volume fraction of the black material in the film | membrane measured by the above-mentioned method was 10 volume%.

<Example 2>
Using the black paint A obtained in Example 1, the infrared transmission was carried out in the same manner as in Example 1 except that the spin coating rotation speed was adjusted so that the film thickness after heat curing was 0.5 μm. A glass substrate with a black film A-2 was obtained.
Using the obtained glass substrate with an infrared transmitting black film A-2, the optical characteristics of the black film and the average dispersed particle diameter of the black material in the film were evaluated in the same manner as in Example 1. The results are shown in Tables 1 to 3.

<Example 3>
Using the black paint A obtained in Example 1, the infrared transmission was carried out in the same manner as in Example 1 except that the spin coating rotation speed was adjusted so that the film thickness after heat curing was 0.13 μm. A glass substrate with a black film A-3 was obtained.
Using the obtained glass substrate with the infrared transmitting black film A-3, the optical characteristics of the black film and the average dispersed particle diameter of the black material in the film were evaluated in the same manner as in Example 1. The results are shown in Tables 1 to 3.

<Example 4>
In addition to 50 g of the black dispersion A obtained in Example 1, 42.09 g of an acrylic resin solution (KAYARAD ZCR-1569H, manufactured by Nippon Kayaku Co., Ltd., nonvolatile content: 70% by mass) as a resin component raw material and dipentaerythritol hexaacrylate 7 .37 g was added, and further 0.61 g of propylene glycol monomethyl ether acetate was added, and the mixture was treated with an ultrasonic disperser for 5 minutes, and left for 1 hour to obtain black paint B. Next, a glass substrate with an infrared transmitting black film B-1 was obtained in the same manner as in Example 1 except that the black paint B was used.
Using the obtained glass substrate with an infrared transmitting black film B-1, the optical characteristics of the black film and the average dispersed particle diameter of the black material in the film were evaluated in the same manner as in Example 1. The results are shown in Tables 1 to 3.

<Example 5>
(Formation of black film)
In 200 ml of pure water kept at 60 ° C., 15.0 g of a tin (Sn) colloid dispersion (average primary particle size: 20 nm, solid content: 20% by mass, manufactured by Sumitomo Osaka Cement Co., Ltd.) and silver (Ag) colloid ( Average particle diameter: 7 nm, solid content: 20% by mass, manufactured by Sumitomo Osaka Cement Co., Ltd. 60.0 g and 0.75% by mass polyvinylpyrrolidone (PVP: manufactured by Tokyo Chemical Industry Co., Ltd., trade name: K15) aqueous solution 100 g were added, A colloidal solution was obtained.
Next, while stirring this colloidal solution, 75 g of 0.05 mol / l nitric acid aqueous solution was slowly added dropwise thereto, and 450.0 g of 10.0% by mass citric acid aqueous solution was further added to prepare a mixed solution.

  Next, this mixed liquid was reacted by stirring for 48 hours at 60 ° C. using a magnetic stirrer, and then washed and concentrated by centrifugation to obtain a colloid liquid C having a black particle concentration of 15.0 mass%. It was. Thereafter, 7.5 g of a comb-type urethane polymer dispersant (manufactured by Big Chemie, trade name “Disper Byk161”, nonvolatile content: 30% by mass) is added to 100.0 g of the colloid liquid C, and then the solvent is removed by an evaporator. Removal and drying gave black powder C. As a result of measuring the water content and the polymer dispersant amount of the obtained black powder C by the above-mentioned method, the water content was 1.5% by mass and the polymer dispersant amount was 13.03% by mass.

When the product phase in the black powder C was identified by the powder X-ray diffraction method, the presence of tin was not confirmed, and the presence of a silver-tin alloy (Ag ₃ Sn and / or Ag ₄ Sn) phase and a silver (Ag) phase. Was confirmed. In addition, as in Example 1, there is a possibility that tin is dissolved in the silver phase.
Further, when the green powder C green compact was analyzed with an electron beam microanalyzer (EPMA) and the content ratio of tin and silver (silver / (silver + tin): mass ratio) was determined, silver / (silver + Tin) = 88.2%.

Subsequently, in the preparation of the black paint A of Example 1, a black paint C was obtained in the same manner as the black paint A except that the black powder C was used instead of the black powder A. Moreover, the glass substrate with infrared rays transmission black film C-1 was obtained by the method similar to Example 1 except having used this black coating material C.
Using the obtained glass substrate with an infrared transmitting black film C-1, the optical characteristics of the black film and the average dispersed particle diameter of the black material in the film were evaluated in the same manner as in Example 1. The results are shown in Tables 1 to 3.

<Example 6>
Using the black paint C obtained in Example 5, the infrared transmission was carried out in the same manner as in Example 5 except that the spin coating rotation speed was adjusted so that the film thickness after heat curing was 0.5 μm. A glass substrate with a black film C-2 was obtained.
Using the obtained glass substrate with an infrared transmitting black film C-2, the optical characteristics of the black film and the average dispersed particle diameter of the black material in the film were evaluated in the same manner as in Example 1. The results are shown in Tables 1 to 3.

<Example 7>
Using the black paint C obtained in Example 5, the infrared transmission was performed in the same manner as in Example 5 except that the spin coating rotation speed was adjusted so that the film thickness after heat curing was 0.13 μm. A glass substrate with a black film C-3 was obtained.
Using the obtained glass substrate with an infrared transmitting black film C-3, the optical characteristics of the black film and the average dispersed particle diameter of the black material in the film were evaluated in the same manner as in Example 1. The results are shown in Tables 1 to 3.

<Example 8>
In addition to 50 g of the black dispersion A obtained in Example 1, 2.05 g of an acrylic resin solution (KAYARAD ZCR-1569H, manufactured by Nippon Kayaku Co., Ltd., nonvolatile content: 70% by mass) as a resin component raw material and dipentaerythritol hexaacrylate 0 .36 g was added, and 0.61 g of propylene glycol monomethyl ether acetate was further added. The mixture was treated with an ultrasonic disperser for 5 minutes, and left for 1 hour to obtain a black paint D. Next, a glass substrate with an infrared transmitting black film D-1 was obtained in the same manner as in Example 1 except that the black paint D was used.
Using the obtained glass substrate with an infrared transmitting black film D-1, the optical characteristics of the black film and the average dispersed particle diameter of the black material in the film were evaluated in the same manner as in Example 1. The results are shown in Tables 1 to 3.

<Example 9>
Preparation of black powder A in Example 1 was the same as that of black powder A except that the comb-type urethane polymer dispersant (manufactured by Big Chemie, trade name Disper Byk161, nonvolatile content: 30% by mass) was 12.5 g. A black powder E was prepared.
Black dispersion E was obtained by adding 81.25 g of propylene glycol monomethyl ether acetate to 18.75 g of the obtained black powder E and irradiating with ultrasonic waves for 20 minutes. To this black dispersion E50 g, 7.37 g of an acrylic resin solution (KAYARAD ZCR-1569H, manufactured by Nippon Kayaku Co., Ltd., nonvolatile content: 70% by mass) and 1.29 g of dipentaerythritol hexaacrylate are further added as a resin component raw material. 0.61 g of propylene glycol monomethyl ether acetate was added, treated with an ultrasonic disperser for 5 minutes, and allowed to stand for 1 hour to obtain black paint E. Next, a glass substrate with an infrared transmitting black film E-1 was obtained in the same manner as in Example 1 except that the black paint E was used.
Using the obtained glass substrate with an infrared transmitting black film E-1, the optical characteristics of the black film and the average dispersed particle diameter of the black material in the film were evaluated in the same manner as in Example 1. The results are shown in Tables 1 to 3.

<Comparative Example 1>
Carbon black (Seast 3 (HAF), manufactured by Tokai Carbon Co., Ltd.), 2.5 g of comb-shaped urethane polymer dispersant (manufactured by Big Chemie, trade name: Disper Byk161, nonvolatile content: 30% by mass), propylene 84.25 g of glycol monomethyl ether acetate was added and irradiated with ultrasonic waves for 20 minutes to obtain a black dispersion F.
In addition, after removing a part of the black dispersion liquid F and removing the solvent with an evaporator and drying to obtain a black powder F, the water content of the black powder F and the amount of the polymer dispersant were measured by the method described above. The amount was 0.1% by mass or less. On the other hand, the amount of the polymer dispersant could not be measured because the mass loss of the carbon black itself occurred in the measurement temperature range.
Next, 8.86 g of an acrylic resin solution (KAYARAD ZCR-1569H, manufactured by Nippon Kayaku Co., Ltd., nonvolatile content: 70% by mass) and 1.55 g of dipentaerythritol hexaacrylate are added to 50 g of this black dispersion F. Further, 0.61 g of propylene glycol monomethyl ether acetate was added, followed by treatment with an ultrasonic disperser for 5 minutes, and left for 1 hour to obtain black paint F.
The average dispersed particle size of carbon black in the black paint F was measured and found to be 145 nm.

In the formation of the black film of Example 1, a glass substrate with a black film F-1 was obtained in the same manner as in Example 1 except that the black paint F was used instead of the black paint A.
Using the obtained glass substrate with the black film F-1, the optical characteristics of the black film, the average dispersed particle diameter of the black material in the film, and the like were evaluated in the same manner as in Example 1. The results are shown in Tables 1 to 3.

  In addition, about the obtained black film | membrane F-1, it observed by TEM by the method similar to Example 1. FIG. A TEM observation photograph of the film cross section is shown in FIG. From this observation photograph, the average dispersed particle size of the dispersed carbon black was also measured by the same method as in Example 1, but the carbon black particles formed a large aggregate and formed a network in the film. As a result, the particle shape and size of each particle could not be confirmed, and the dispersed particle size could not be calculated.

<Comparative example 2>
Using the black paint F obtained in Comparative Example 1, the black film was prepared in the same manner as in Comparative Example 1, except that the spin coating rotation speed was adjusted so that the film thickness after heat curing was 0.5 μm. A glass substrate with F-2 was obtained.
Using the obtained glass substrate with the black film F-2, the optical characteristics of the black film and the average dispersed particle diameter of the black material in the film were evaluated in the same manner as in Example 1. The results are shown in Tables 1 to 3. The average dispersed particle size of carbon black could not be calculated for the same reason as in Comparative Example 1.

<Comparative Example 3>
Using the black paint F obtained in Comparative Example 1, the black film was prepared in the same manner as in Comparative Example 1 except that the spin coating rotation speed was adjusted so that the film thickness after heat curing was 0.13 μm. A glass substrate with F-3 was obtained.
Using the obtained glass substrate with the black film F-3, the optical characteristics of the black film and the average dispersed particle diameter of the black material in the film were evaluated in the same manner as in Example 1. The results are shown in Tables 1 to 3. The average dispersed particle size of carbon black could not be calculated for the same reason as in Comparative Example 1.

<Comparative Example 4>
In addition to 16 g of the black dispersion F prepared in Comparative Example 1, 16.33 g of an acrylic resin solution (KAYARAD ZCR-1569H, manufactured by Nippon Kayaku Co., Ltd., nonvolatile content: 70% by mass) and dipentaerythritol hexaacrylate as a resin component raw material 2.86 g was added, and 3.68 g of propylene glycol monomethyl ether acetate was further added, followed by treatment with an ultrasonic disperser for 5 minutes. Next, a glass substrate with a black film G-1 was obtained in the same manner as in Example 1 except that the black paint G was used.
Using the obtained glass substrate with the black film G-1, the optical characteristics of the black film, the average dispersed particle diameter of the black material in the film, and the like were evaluated in the same manner as in Example 1. The results are shown in Tables 1 to 3. The average dispersed particle size of carbon black could not be calculated for the same reason as in Comparative Example 1.

<Comparative Example 5>
In the preparation of black powder A in Example 1, black powder A was used except that the amount of addition of a comb-type urethane-based polymer dispersant (manufactured by Big Chemie, trade name Disper Byk161, nonvolatile content: 30% by mass) was 1.5 g. A black powder H was obtained by the same method. Using this black powder H, an attempt was made to produce a black dispersion in the same manner as in Example 1. However, a sufficient dispersion state could not be obtained, and a dispersion could not be produced. The results are shown in Table 1 (Comparative Examples 5 to 8 are not evaluated for optical density or the like because film formation is impossible and film properties are poor).

<Comparative Example 6>
In the preparation of the black powder A in Example 1, the same as the black powder A, except that the amount of addition of the comb-type urethane polymer dispersant (manufactured by Big Chemie, trade name Disper Byk161, nonvolatile content: 30% by mass) was 25 g. In this way, black powder I was obtained. A glass substrate with a black film I-1 was produced in the same manner as in Example 1 except that this black powder I was used, but many agglomerates were present on the film surface and many pinholes were generated. It was confirmed that it was not suitable for the measurement of film properties. The results are shown in Table 1.

<Comparative Example 7>
In the preparation of black powder A in Example 1, a polycarboxylic acid polymer dispersant (Kao Co., Ltd.) was used instead of the comb-type urethane polymer dispersant (manufactured by Big Chemie, trade name Disper Byk161, nonvolatile content 30% by mass). A black powder J was obtained in the same manner as the black powder A except that 7.5 g was used. Using this black powder J, an attempt was made to produce a black dispersion in the same manner as in Example 1. However, a sufficient dispersion state could not be obtained, and a dispersion could not be produced. The results are shown in Table 1.

<Comparative Example 8>
In the preparation of the black powder A in Example 1, the black powder K was treated in the same manner as the black powder A, except that the drying with the evaporator after the treatment with the polymer dispersant was interrupted and the water content was changed to 5.2% by mass. Was prepared. A glass substrate with a black film K-1 was produced in the same manner as in Example 1 except that this black powder K was used. However, in the solvent evaporation process after spin coating, aggregation occurred in the coating film. It was confirmed that the coating surface became white and cloudy. The results are shown in Table 1.

  As shown in Tables 1 to 3, the infrared transmitting black films of Examples 1 to 9 have excellent transmittance in the near-infrared region, although the light-shielding property in the visible light region is high. Was confirmed. In addition, even if the content of the black material in the film and the film thickness itself are changed, there is no difference in the dispersed particle diameter of the black material and the transmission characteristics at each wavelength, and high visible light shielding properties and excellent infrared transmission It was confirmed that the density of the black filter can be adjusted by controlling the black material content in the film and the film thickness itself.

On the other hand, in Comparative Examples 1 to 4, there was no significant change in the transmittance in the visible light region and the infrared region, and there was no transparency in the infrared region.
In Comparative Example 5, the amount of the polymer dispersant added was too small, so that the black powder was not sufficiently dispersed and a dispersion could not be prepared. Further, in Comparative Example 6, since the amount of the polymer dispersant added was too large and the dispersion state was not stable, the black powder aggregated during the formation of the black film, and a good black film could not be obtained. In Comparative Example 7, the affinity between the black powder and the polymer dispersant is poor, and the black powder is not sufficiently coated with the polymer dispersant. could not. Furthermore, in Comparative Example 8, since the amount of water in the black powder was too large, white turbidity occurred when the black film was formed (when the solvent was volatilized). This is because the amount of the solvent having good compatibility with the resin contained decreases, and conversely the content of water with poor compatibility increases relatively, so that a part of the water precipitates in the resin, and the appearance of the film This seems to be because it looks white.

<Color filter characteristics>
(Production of black matrix)
Except that each black paint prepared in Examples 1 to 9 was used as each light-shielding photosensitive resin composition coating solution, and a pattern mask composed of a normal mesh pattern (line width 20 μm) was used as a black matrix pattern. The black films of Examples 1 to 9 were formed in a mesh pattern on a 10 cm square TFT element substrate using the black matrix production method described in Paragraph No. 0301 of JP-A-2009-75446. A black matrix was obtained.
At this time, since the coating film has infrared transparency, it was possible to easily align the fine line pattern with the TFT element on the substrate in pattern formation.

(Production and evaluation of color filters)
For the black matrix (light-shielded image) having the black film of Examples 1 to 9 obtained above, the transfer type photosensitive resin film described in paragraph numbers 0158 to 0170 of JP-A-2006-251237 is used. A colored pattern having a predetermined size and shape of red, green, and blue was formed by the conventional color filter manufacturing method, and a color filter was manufactured on the TFT element substrate.
Next, a counter electrode substrate provided with a transparent common electrode was disposed at a position facing the color filter on the TFT element substrate, and a liquid crystal material was sealed between the color filter and the counter electrode substrate to form a liquid crystal cell. Polarizing plates were attached to both surfaces of the obtained liquid crystal cell, and white LEDs as a backlight were disposed on the back side of the TFT element substrate.
The display characteristics of the thus manufactured COA type liquid crystal display device were evaluated. As a result, it was confirmed that a liquid crystal display device provided with a color filter using each of the black matrices exhibits good display characteristics. In particular, since the alignment between the TFT element and the black matrix was good, color mixing between R, G, and B colors was well prevented.

  The infrared transmitting black film of the present invention has an excellent light-shielding property for visible light, and has a transmittance of a certain value or more for infrared rays. It can use suitably for various black protective covers including a protective cover. Further, since it can be applied to a black matrix of COA type or BOA type, it can be suitably used for various image display devices.

Claims (7)

Comprising a black material and a resin component,
The average dispersed particle size in the film of the black material is 1 nm or more and 100 nm or less,
Transmittance per 1 μm thickness at a wavelength of 560 nm (T ₅₆₀ ) is less than 40%, and optical density based on transmittance at a wavelength of 560 nm (OD ₅₆₀ ) and optical density based on transmittance at a wavelength of 950 nm (OD ₉₅₀ ) An infrared transmitting black film having a ratio (OD ₉₅₀ / OD ₅₆₀ ) of 0.35 or less. The ratio (OD _NIR ) between the optical density (OD ₅₆₀ ) based on the transmittance at the wavelength of 560 nm and the optical density (OD _NIR ) based on the transmittance at each wavelength in the near infrared (NIR) wavelength region of the wavelength of 800 nm to 2500 nm. / OD ₅₆₀₎ are infrared transmitting black film according to claim 1 is 0.40 or less.   3. The infrared transmitting black film according to claim 1, wherein a volume fraction of the black material is 1.0 volume% or more and 25 volume% or less.   The infrared transmitting black film according to any one of claims 1 to 3, wherein the black material is metal fine particles mainly composed of silver and tin.   The metal fine particles are composed of silver tin alloy fine particles, or mixed fine particles of the silver tin alloy fine particles and silver fine particles, and the silver component content in the silver tin alloy fine particles is 45% by mass or more and 95% by mass. 5. The infrared transmitting black film according to claim 4, wherein the silver component content relative to the total amount of silver and tin in the mixed fine particles of the silver-tin alloy fine particles and the silver fine particles is 45 mass% or more and 95 mass% or less.   The base material with a film | membrane which has an infrared rays transmission black film in any one of Claims 1 thru | or 5.   An image display device comprising the infrared transmitting black film according to claim 1.