JP7484378B2 - Infrared reflective film dispersion and method for producing infrared reflective film dispersion - Google Patents

Description

The present invention relates to an infrared reflective film dispersion and a method for producing an infrared reflective film dispersion.

In recent years, in order to improve energy conservation, heat-shielding materials that block heat rays have been used in windows for automobiles, trains, and other means of transportation, as well as in windows for buildings.

For example, Patent Document 1 discloses a heat ray shielding material having a film with an optical function of preventing reflection of incident light of a second incident light wavelength, the heat ray shielding material including a base substrate having a first refractive index, a metal particle-containing layer containing a plurality of metal particles, and a dielectric layer having a second refractive index, the substrate, the metal particle-containing layer, and the dielectric layer being stacked in this order to form a laminated structure, the dielectric layer having a thickness such that when incident light is incident on the laminated structure from the surface side of the dielectric layer, the reflected light on the surface of the dielectric layer interferes with and is cancelled by the reflected light on the interface between the dielectric layer and the metal particle-containing layer.

International Publication No. 2016/208331

However, the film used in the heat ray shielding material disclosed in Patent Document 1 had to be a single film that covered the entire area that shielded against heat rays, and depending on the size of the film, the heat ray shielding properties could vary within the film, and the shape of the film could be restricted. In particular, the film used in the heat ray shielding material disclosed in Patent Document 1 had to be formed into multiple layers, each with a specified thickness, making it difficult to manufacture.

For this reason, the film used in the heat ray shielding material disclosed in Patent Document 1 required strict manufacturing conditions to achieve the desired performance, and productivity was low.

One aspect of the present invention aims to provide an infrared reflective film dispersion that can reflect infrared rays and has excellent productivity.

In one aspect of the present invention, a thermal expansion coefficient measuring device is provided, comprising: a resin; and infrared ray reflective film-containing particles disposed in the resin,
The infrared reflective film-containing particle has a substrate and an infrared reflective film disposed on the substrate and containing one or more types selected from metals and oxides,
The infrared reflective film contains a composite tungsten oxide,
The composite tungsten oxide provides an infrared reflective film dispersion represented by the general formula MxWOy ₍ wherein _M is one or more elements selected from Cs, Rb, K, Tl, In, Ba, Li, Ca, Sr, Fe, Sn, Al, Cu, and Na, and 0.001≦x≦1, 2.2≦y≦3.0).

In one aspect of the present invention, it is possible to provide an infrared reflective film dispersion that can reflect infrared rays and has excellent productivity.

1 is a schematic cross-sectional view of an infrared reflective film dispersion according to one embodiment of the present disclosure. FIG. 2 is an explanatory diagram of a method for producing an infrared reflective film dispersion according to one embodiment of the present disclosure. FIG. 4 is an explanatory diagram of a method for producing an infrared reflective film dispersion according to another embodiment of the present disclosure. 3 shows reflectance spectra of the infrared reflective film dispersion produced in Example 1 and the infrared reflective film laminate of Reference Example 1.

[Infrared reflective film dispersion]
The infrared reflective film dispersion of this embodiment will be described.

Figure 1 shows a schematic cross-sectional view of the infrared reflective film dispersion 10 of this embodiment taken along a plane parallel to the thickness direction.

As shown in FIG. 1, the infrared reflective film dispersion 10 of this embodiment can have a resin 11 and infrared reflective film-containing particles 12 arranged in the resin 11. The infrared reflective film-containing particles 12 can have a substrate 121 and an infrared reflective film 122 arranged on the substrate 121 and containing one or more types selected from metals and oxides.

The infrared reflective film dispersion 10 of this embodiment has a structure in which infrared reflective film-containing particles 12, each having an infrared reflective film 122 arranged on a substrate 121, are arranged in a resin 11, as described above. According to the infrared reflective film dispersion 10 of this embodiment, since it can be manufactured by dispersing infrared reflective film-containing particles having an infrared reflective film 122 in a resin, it can be manufactured easily and with good productivity. In particular, the infrared reflective film of the infrared reflective film dispersion 10 of this embodiment does not need to be a single infrared reflective film, but is arranged on multiple substrates 121 contained in the resin 11. Therefore, the infrared reflective film dispersion 10 of this embodiment has small differences in infrared reflective properties depending on the location, and can be made into any size and shape.

Hereinafter, each member of the infrared reflective film dispersion of this embodiment will be described.
(1) Infrared-Reflective Film-Containing Particle The infrared-reflective film-containing particle can have a substrate 121 and an infrared-reflecting film 122 disposed on the substrate 121 .
(1-1) Substrate The substrate 121 may be any substrate capable of supporting the infrared reflective film 122, and the shape and the like of the substrate 121 are not particularly limited. However, since the substrate 121 is dispersed in the resin 11 of the infrared reflective film dispersion 10 as the infrared reflective film-containing particles 12, it is preferable to select the shape and size of the substrate 121 according to the size and the like required for the infrared reflective film dispersion 10.

For example, the substrate 121 can have a plate-like shape as shown in FIG. 1. The thickness of the substrate 121 is not particularly limited, but is preferably 0.05 μm or more and 100 μm or less, and more preferably 0.1 μm or more and 50 μm or less.

The material of the substrate 121 is not particularly limited, but may be one or more selected from glass, resin, and inorganic materials. The resin is not particularly limited, but when it is required to increase the visible light transmittance of the entire infrared reflective film dispersion, a transparent resin having visible light transmittance is preferable. For example, one or more resins selected from the group consisting of polyethylene resin, polyvinyl chloride resin, polyvinylidene chloride resin, polyvinyl alcohol resin, polystyrene resin, polypropylene resin, ethylene vinyl acetate copolymer, polyester resin, fluororesin, polycarbonate resin, acrylic resin, and polyvinyl butyral resin can be preferably used.

In addition, when it is required to increase the visible light transmittance of the entire infrared reflective film dispersion, the inorganic material is preferably an inorganic material having visible light transmittance. As the inorganic material, for example, one or more selected from titanium dioxide, aluminum oxide, tin oxide, tin-doped indium oxide (ITO), antimony-doped tin oxide (ATO), zirconium oxide, silicon dioxide, yttrium aluminum garnet (YAG), and yttrium oxide can be used.

The infrared reflective film dispersion 10 may contain substrates made of different materials at the same time, for example, a mixture of a substrate made of glass and a substrate made of resin.
(1-2) Infrared Reflecting Film The infrared reflecting film 122 can be used without any particular limitation as long as it is a film that can reflect infrared rays. The infrared reflecting film preferably contains at least one selected from, for example, silver, gold, aluminum, platinum, rhodium, copper, nickel, zinc oxide, indium oxide, tin-doped indium oxide, titanium oxide, and composite tungsten oxide. Since at least one selected from the above material group has excellent infrared reflecting properties, an infrared reflecting film dispersion having excellent heat ray shielding properties can be obtained by making the infrared reflecting film contain at least one selected from the above material. The infrared reflecting film can also be composed of at least one selected from the above material group. However, even in this case, it does not exclude the inclusion of unavoidable impurities.

The infrared reflective film particularly contains a composite tungsten oxide, and the composite tungsten oxide is more preferably _represented by the general formula _MxWOy (wherein M is one or more elements selected from Cs, Rb, K, Tl, In, Ba, Li, Ca, Sr, Fe, Sn, Al, Cu, and Na, and 0.001≦x≦1, 2.2≦y≦3.0). This is because the composite tungsten oxide is particularly excellent in infrared reflective properties, and by containing the composite tungsten oxide in the infrared reflective film, an infrared reflective film dispersion excellent in heat ray shielding properties can be obtained.

The infrared reflective film can also be made of composite tungsten oxide. However, this does not exclude the possibility of unavoidable impurities being mixed in.

As described above, in the general formula M _x WO _y , the atomic ratio x of element M to W (tungsten) is preferably 0.001≦x≦1. This is because by making x 0.001 or more, sufficient free electrons can be generated in the composite tungsten oxide, and the infrared shielding effect can be particularly improved. Also, by making x 1 or less, the generation of impurity phase in the composite tungsten oxide phase can be suppressed.

In the above general formula, the composite tungsten oxide preferably has an atomic ratio y of O (oxygen) to W (tungsten) of 2.2≦y≦3.0. This is because by making y 2.2 or more, it is possible to suppress the formation of undesired _WO2 phase in the composite tungsten oxide phase. In addition, by making y 3.0 or less, it is possible to generate a sufficient amount of free electrons to obtain an infrared shielding effect, and it is possible to particularly enhance the infrared shielding effect.

Composite tungsten oxides are known to have crystalline structures such as hexagonal, cubic, tetragonal, and orthorhombic, as well as amorphous structures. When the infrared reflective film 122 contains a composite tungsten oxide, the structure is not particularly limited, and it can contain one or more selected from the above crystalline structures and amorphous structures. However, it is preferable that the composite tungsten oxide contains a hexagonal structure, which has particularly high infrared reflection.

When the element M constituting the composite tungsten _{oxide MxWOy} contains one or more elements selected from among Cs, K, Rb, Tl, In, and Ba, a hexagonal crystal is easily formed. Therefore, it is more preferable that the element M contains one or more elements selected from among Cs, K, Rb, Tl, In, and Ba, and it is even more preferable that the element M is one or more elements selected from among Cs, K, Rb, Tl, In, and Ba.

Particularly preferred examples of the composite tungsten oxide contained in _the infrared reflective film include one or more selected from _{Cs0.33WOy , Cs0.03Rb0.30WOy , Rb0.33WOy , K0.33WOy , Ba0.33WOy , etc.} In this case, it is also preferable that y satisfies 2.2≦y≦3.0.

Note that, although FIG. 1 shows an example in which the infrared reflective film 122 is disposed only on one surface 121A of the substrate 121, this is not intended to be limiting. For example, the infrared reflective film 122 may be disposed on both one surface 121A of the substrate 121 and the other surface 121B located opposite the one surface 121A.

The thickness c of the infrared reflective film can be appropriately adjusted depending on the type of material of the infrared reflective film, and is not particularly limited. However, when it is required to increase the visible light transmittance of the infrared reflective film dispersion, it is preferable to set the thickness c to 800 nm or less. In addition, for example, when the infrared reflective film contains a composite tungsten oxide, it is desirable to set the thickness c to 20 nm or more so that sufficient infrared reflective performance can be obtained. In addition, even when the infrared reflective film contains a component other than the composite tungsten oxide, it is preferable to set the thickness c to 20 nm or more, for example, because it can exhibit particularly high infrared reflective performance.
(1-3) Shape of infrared reflective film-containing particle As described above, the infrared reflective film-containing particle is not particularly limited as long as it contains a substrate and an infrared reflective film disposed on the substrate.

The infrared reflective film-containing particles preferably have an aspect ratio a/c, which is the ratio of the length a of the longest part in the film surface direction of the infrared reflective film to the film thickness c, of 3 or more.

This is because by making the aspect ratio 3 or more, it is possible to improve the infrared reflection characteristics in particular.

The upper limit of the above aspect ratio is not particularly limited, but it is preferable to set it to 100 or less, for example, from the viewpoint of maintaining a certain level of strength of the material.

The length of the longest part of the infrared reflective film in the film surface direction means the length of the longest part of the top surface of the infrared reflective film when viewed in a plane perpendicular to the film thickness direction, for example, along arrow A in Figure 1.

The shapes of the infrared reflective film and the substrate supporting the infrared reflective film are not particularly limited, and may have any shape.
(2) Resin The resin in which the infrared reflective film-containing particles are dispersed is not particularly limited, and various resins can be used. When the substrate is made of a resin, the same resin as that of the substrate can be used.

When it is required to increase the visible light transmittance of the entire infrared reflective film dispersion, it is preferable to use a transparent resin that has visible light transmittance.

As the resin, for example, one or more resins selected from the group consisting of polyethylene resin, polyvinyl chloride resin, polyvinylidene chloride resin, polyvinyl alcohol resin, polystyrene resin, polypropylene resin, ethylene-vinyl acetate copolymer, polyester resin, fluororesin, polycarbonate resin, acrylic resin, and polyvinyl butyral resin can be preferably used.
(3) Infrared reflective film dispersion The infrared reflective film dispersion can be formed in a place where infrared reflective properties are required, and the shape is not particularly limited and can be any shape. Therefore, it can be a flat plate-shaped body as shown in Figure 1, or a bent plate-shaped body depending on the place where it is placed. And it is preferable that it has visible light transmittance.

In the infrared reflective film dispersion 10 of this embodiment, it is preferable that the infrared reflective films 122 of the multiple infrared reflective film-containing particles 12 are arranged along the surface 10A of the infrared reflective film dispersion 10. Here, the infrared reflective film 122 is arranged along the surface 10A of the infrared reflective film dispersion 10 does not mean that the two are arranged completely parallel, but rather that the angle between the two is within a predetermined angle depending on the required reflection characteristics, etc., and is arranged approximately parallel.

The infrared reflective film dispersion of the present embodiment can be used alone, but can also be disposed on a substrate such as glass or resin, or disposed between substrates such as glass or resin to form a laminated infrared reflective film dispersion for use.
[Method of manufacturing infrared reflective film dispersion]
A method for producing the infrared reflective film dispersion of this embodiment will be described. According to the method for producing the infrared reflective film dispersion of this embodiment, the infrared reflective film dispersion described above can be produced. Therefore, some of the matters already described will not be described.
(1) First Manufacturing Method The manufacturing method of the infrared reflective film dispersion of the present embodiment can include, for example, the following steps.

An infrared reflective film laminate producing step of forming an infrared reflective film containing one or more selected from metals and oxides on a plate-like substrate to produce an infrared reflective film laminate.
A micronization step in which the infrared reflective film laminate is micronized to form infrared reflective film-containing particles in which the infrared reflective film is disposed on the micronized plate-like substrate.
A molding process in which the infrared reflective film-containing particles and a resin are mixed and molded.
Each step will be described below with reference to FIG.
(Infrared reflective film laminate manufacturing process)
In the infrared reflective film laminate preparation step, as shown in FIG. 2(A), an infrared reflective film 22 is formed on a plate-shaped substrate 21, thereby preparing an infrared reflective film laminate 20.

The plate-shaped substrate 21 is a member that will become the substrate for the infrared reflective film-containing particles when it is refined in the refinement process described below, and other than having a plate-like shape, the same material as the substrate described above can be used.

The thickness of the plate-shaped substrate 21 is not particularly limited, but is preferably, for example, 0.05 μm or more and 100 μm or less, and more preferably 0.1 μm or more and 50 μm or less.

As described above, the infrared reflective film can be any film capable of reflecting infrared rays, and is not particularly limited. The infrared reflective film preferably contains at least one selected from the group consisting of silver, gold, aluminum, platinum, rhodium, copper, nickel, zinc oxide, indium oxide, tin-doped indium oxide, titanium oxide, and composite tungsten oxide. Since at least one selected from the above materials has excellent infrared reflective properties, an infrared reflective film dispersion having excellent heat shielding properties can be obtained by forming the infrared reflective film containing at least one selected from the above group of materials. The infrared reflective film can also be composed of at least one selected from the above group of materials. However, this does not exclude the inclusion of unavoidable impurities even in this case.

The infrared reflective film particularly contains a composite tungsten oxide, and the composite tungsten oxide is more preferably _represented by the general formula _MxWOy (wherein M is one or more elements selected from Cs, Rb, K, Tl, In, Ba, Li, Ca, Sr, Fe, Sn, Al, Cu, and Na, and 0.001≦x≦1, 2.2≦y≦3.0). This is because the composite tungsten oxide is particularly excellent in infrared reflective properties, and by containing the composite tungsten oxide in the infrared reflective film, an infrared reflective film dispersion excellent in heat ray shielding properties can be obtained.

The infrared reflective film can also be made of composite tungsten oxide. However, this does not exclude the possibility of unavoidable impurities being mixed in.

The method of forming the infrared reflective film is not particularly limited, and can be selected depending on the type of material of the infrared reflective film to be formed. The infrared reflective film can be formed using a physical deposition method selected from, for example, vacuum deposition, sputtering, ion plating, ion beam, etc., various chemical vapor deposition methods (CVD methods), solution coating, dipping, spraying, electroless plating, electrolytic plating, etc. The infrared reflective film can also be formed by combining multiple methods.

In particular, it is preferable to form the infrared reflective film by using a sputtering method. This is because, when a film is formed by the sputtering method, the energy of the film-forming particles is large, so that a dense film with strong adhesion can be obtained. In addition, the sputtering method has a stable film-forming process, and the film quality and film thickness can be controlled with high precision. Furthermore, the sputtering method can form films of high-melting-point metals, alloys, and compounds, and can also form films of oxides, nitrides, etc. by introducing reactive gases, so that the composition can be adjusted relatively easily.
(Micronization process)
In the microparticulation step, the infrared reflective film laminate 20 produced in the infrared reflective film laminate production step can be microparticulated to form the infrared reflective film-containing particles 12 .

The method of micronization used in the micronization step is not particularly limited, and any micronization method can be used. Examples of the micronization method include cutting the infrared reflective film laminate by a cutting means, mechanical grinding by a grinder, wet grinding using a vibration mill, ball mill, jet mill, etc., dry grinding, grinding in an ultrasonic water bath, etc.

When cutting the infrared reflective film laminate using a cutting means, a laser or the like can be used as the cutting means.

When grinding using a grinder, wet grinding or dry grinding can be used as described above.

When wet grinding is performed, the liquid medium can be any liquid as long as it is a solvent that does not dissolve the plate-like substrate that constitutes the infrared reflective film laminate or the infrared reflective film.

The liquid medium may be one or more selected from the following: water; alcohols such as methanol, ethanol, isopropanol, n-butyl alcohol, t-butyl alcohol, and ethylene glycol; ketones such as acetone and methyl ethyl ketone; esters such as ethyl acetate; halides such as chloroform and methylene chloride; olefins such as butane and hexane; ethers such as tetrahydrofuran (THF), butyl ether, and dioxane; aromatics such as benzene, xylene, and toluene; and amides such as N,N-dimethylformamide (DMF) and dimethylacetamide (DMAc).

When performing dry grinding, the infrared reflective film laminate can be cooled, for example, with liquid nitrogen to increase its hardness before grinding.

After the micronization process, classification can be performed to obtain the desired particle size. As a classification method, a dry classifier or the like can be used. For example, a sieving machine using a sieve net, a gravity classifier that classifies coarse particles and fine powders based on the difference between the settling velocity and the upward flow velocity of a horizontal flow type or an upward flow type, a centrifugal classifier that uses the settling of particles in a centrifugal field, and an inertial classifier that classifies particles with high inertia by suddenly changing the direction of an airflow containing particles to move them away from the flow line.

In the micronization process, it is preferable to micronize the infrared reflective film laminate so that the aspect ratio a/c, which is the ratio of the length a of the longest part in the film surface direction of the resulting infrared reflective film to the film thickness c, is 3 or more.

2(B), an infrared reflective film-containing particle 12 can be obtained in which an infrared reflective film 122 is disposed on a substrate 121 which is a micronized plate-like substrate 21. The infrared reflective film 122 is also micronized together with the plate-like substrate 21, and is finer than the infrared reflective film 22 before the micronization step, i.e., the infrared reflective film before micronization.
(Molding process)
In the molding step, as shown in FIG. 2(C), the infrared reflective film-containing particles 12 obtained in the micro-fine processing step and a resin 11 are kneaded together, and the resulting mixture can be molded into a desired shape as shown in FIG. 2(D).

The resins that are suitable for use have already been explained, so we will not repeat the explanation here.

In the molding process, for example, the infrared reflective film-containing particles, resin powder or pellets, and other additives such as plasticizers, if necessary, can be mixed, melted, and kneaded. The infrared reflective film dispersion can then be molded into the desired shape using a molding method.

For example, a melt of the infrared reflective film dispersion and resin can be molded into a sheet by melt extrusion molding using a T-die or the like. The molded sheet can be biaxially stretched to obtain an infrared reflective film, which is the infrared reflective film dispersion.

The method for producing the infrared reflective film dispersion of this embodiment may include any step other than the steps described above.
(Heat treatment process)
The method for producing the infrared reflective film dispersion of this embodiment may also include, for example, a heat treatment step in which the infrared reflective film is formed on the plate-like substrate and then heat-treated.

By carrying out the heat treatment process, the infrared reflective properties of the infrared reflective film can be particularly improved. The conditions for the heat treatment process are not particularly limited and can be selected according to the type of infrared reflective film, etc.

For example, when the infrared reflective film contains a composite tungsten oxide, it is preferable to perform heat treatment in an inert gas atmosphere or a reducing atmosphere at 400°C to 700°C. Examples of the inert gas atmosphere include one or more atmospheres selected from nitrogen and argon. Examples of the reducing atmosphere include a mixed gas atmosphere of an inert gas and hydrogen, such as a mixed atmosphere of nitrogen and hydrogen or a mixed atmosphere of argon and hydrogen.

By performing heat treatment at 400°C or higher, the crystallinity of the composite tungsten oxide contained in the formed infrared reflective film, particularly the content of hexagonal crystals, can be increased, and the infrared reflective properties can be improved. However, if the heat treatment temperature is too high, the infrared reflective film may react with the substrate or peel off from the substrate, so it is preferable to keep the heat treatment temperature at 700°C or lower.

The heat treatment time is not particularly limited, but can be, for example, from 5 minutes to 60 minutes.
The heat treatment process is not limited to the above conditions, and can be performed, for example, in an inert gas atmosphere or a reducing atmosphere, using a xenon flash lamp or the like. When a xenon flash lamp is used, the infrared reflective film closer to the lamp becomes hotter than the substrate, so the infrared reflective film can be instantaneously heat-treated at a temperature exceeding 700°C while preventing reaction with the substrate or peeling, and the infrared reflective properties can be further improved. When performing heat treatment using a xenon flash lamp, the light irradiation conditions are not particularly limited, but for example, the flash time (pulse width) per flash is preferably 10 milliseconds or less. In addition, the number of flashes during the heat treatment process is preferably 200 times or more and 5000 times or less.

The heat treatment step can be carried out, for example, after the infrared reflective film laminate production step, and is preferably carried out before the micro-finishing step.
(2) Second Manufacturing Method The second manufacturing method, which is another embodiment of the manufacturing method of the infrared reflective film dispersion of the present embodiment, can have, for example, the following steps.

A film-forming process for forming an infrared reflective film containing one or more types selected from metals and oxides on a plate-shaped substrate having a film-forming substrate in which a support substrate, a release layer, and a plate-shaped substrate are laminated in that order.
A peeling step of dissolving the release layer and peeling off the infrared reflective film laminate, in which the infrared reflective film is formed on the plate-like substrate, from the supporting substrate.
A micronization step in which the infrared reflective film laminate is micronized to form infrared reflective film-containing particles in which the infrared reflective film is disposed on the micronized plate-like substrate.

A molding process in which the infrared reflective film-containing particles and a resin are mixed and molded.
(Film forming process)
In the film formation process, as shown in FIG. 3(A), a film formation substrate 31 is formed in which a support substrate 311, a release layer 312, and a plate-shaped substrate 313 are laminated in that order, and an infrared reflective film 32 containing one or more types selected from metals and oxides can be formed on the plate-shaped substrate 313.

The material of the support substrate 311 is not particularly limited, and can be, for example, one or more selected from metal materials, polymeric materials, oxide materials, glass, etc.

Metal materials that are generally used for applications such as supports are used. Specific examples include various stainless steels (SUS) such as SUS304, SUS316, SUS316L, SUS420J2, and SUS630, gold, platinum, silver, copper, nickel, cobalt, titanium, iron, aluminum, tin, various alloys such as nickel-titanium (Ni-Ti) alloys, nickel-cobalt (Ni-Co) alloys, cobalt-chromium (Co-Cr) alloys, and zinc-tungsten (Zn-W) alloys, inorganic materials such as various ceramic materials, and metal-ceramic composites. These may be used alone or in combination of two or more.

As the polymeric material, various resin films can be used. For example, one or more selected from polyolefin films such as polyethylene and polypropylene, polyester films such as polyethylene terephthalate and polyethylene naphthalate, polyvinyl chloride, cellulose triacetate, water-soluble films, etc. can be used. As the water-soluble film, one or more films selected from naturally occurring starch, gelatin, semi-synthetic cellulose derivatives such as carboxymethylcellulose (CMC) and methylcellulose (MC), polyvinyl alcohol (PVA), polyacrylic acid polymers, polyacrylamide (PAM), polyethylene oxide (PEO), etc. can be used.

As the polymer material, polyester film or water-soluble film can be preferably used. As the polyester film, a polyester film having film-forming properties and having a dicarboxylic acid component and a diol component as main components is preferable.

Among the polyester films mentioned above, from the viewpoints of transparency, mechanical strength, dimensional stability, etc., it is preferable to use terephthalic acid or 2,6-naphthalenedicarboxylic acid as the dicarboxylic acid component, and it is preferable to use ethylene glycol or 1,4-cyclohexanedimethanol as the main component of the diol component. Among them, polyesters whose main components are polyethylene terephthalate or polyethylene naphthalate, copolymer polyesters consisting of terephthalic acid, 2,6-naphthalenedicarboxylic acid, and ethylene glycol, and polyester films whose main components are mixtures of two or more of these polyesters are preferable.

As the oxide material, one or more selected from titanium dioxide, aluminum oxide, zirconium oxide, silicon dioxide, etc. can be used.

The thickness of the support substrate is not particularly limited, but is preferably 0.01 mm or more and 10 mm or less, and more preferably 0.05 mm or more and 5 mm or less. The support substrate may be a laminate of two or more sheets, in which case the support substrate may be a laminate of substrates made of different materials, or a laminate of substrates made of the same material.

The release layer may be configured so as to be able to release the plate-shaped substrate in the release step described below, and may be, for example, a layer made of an acrylic acid ester copolymer resin. There are no particular limitations on the method for forming the release layer, and it may be applied or formed into a film by, for example, a bar coater method, a dipping method, a spin coater method, a spray method, or the like.

If a water-soluble film is used as the support substrate, a release layer does not need to be provided.

The plate-like substrate and the infrared reflective film can be configured in the same manner as in the first manufacturing method, and therefore a description thereof will be omitted here.
(Peeling process)
In the peeling process, the peeling layer 312 of the film-forming substrate 31 shown in FIG. 3(A) is dissolved, and the infrared reflective film laminate 30 in which the infrared reflective film 32 is formed on the plate-shaped substrate 313 can be peeled off from the substrate as shown in FIG. 3(B).

In the peeling process, for example, the laminate produced in the film formation process, in which an infrared reflective film is formed on a film formation substrate, is immersed in an ultrasonic water bath, whereby the laminate of the plate-shaped substrate and the infrared reflective film can be peeled off from the support substrate.
(Miniaturization process, molding process)
In the micronizing step, the infrared reflective film laminate is micronized to form infrared reflective film-containing particles, and in the molding step, the infrared reflective film-containing particles and a resin are kneaded and molded.

Therefore, infrared-reflecting film-containing particles can be produced in the same manner as shown in FIG. 2(B), except that the infrared-reflecting film-containing particles obtained are used instead of the infrared-reflecting film-laminate 20 as the material to be supplied. Then, infrared-reflecting film dispersions can be produced in the same manner as shown in FIG. 2(C) and FIG. 2(D), except that the obtained infrared-reflecting film-containing particles are used.

In this way, the micro-refining process and molding process can be carried out in the same way as in the first manufacturing method, so a description will be omitted here.

The second manufacturing method may also include any additional steps, for example the heat treatment step already described in the first manufacturing method.

The conditions for the heat treatment process have already been explained, so a detailed explanation will be omitted here. The heat treatment process can be carried out, for example, after the film formation process and before the microfabrication process. It is particularly preferable to carry out the heat treatment process between the peeling process and the microfabrication process.

In the second manufacturing method, when forming an infrared reflective film in the film formation process, a film formation substrate including a support substrate that is removed in the peeling process is used. Therefore, even if the plate-shaped substrate is thin, the infrared reflective film can be formed without compromising ease of handling.

According to the manufacturing method of the infrared reflective film dispersion of this embodiment described above, the infrared reflective film dispersion can be easily manufactured by dispersing infrared reflective film-containing particles in a resin and molding the resin. Therefore, the infrared reflective film dispersion can be manufactured with high productivity.

In addition, the infrared reflective film dispersion obtained by the manufacturing method of the infrared reflective film dispersion of this embodiment is not a single infrared reflective film, but is dispersed in the resin as infrared reflective film-containing particles as described above. Therefore, it is possible to suppress differences in infrared reflectivity within the dispersion and to obtain an infrared reflective film dispersion with uniform infrared reflection characteristics. Furthermore, it is possible to obtain an infrared reflective film dispersion of the desired shape without being restricted by the location of formation.

The present invention will be described in more detail below with reference to examples, but the present invention is not limited thereto.
[Example 1]
Cesium tungsten oxide powder (manufactured by Sumitomo Metal Mining Co., Ltd., model number: YM-01) with an atomic ratio Cs/W of 0.33 of cesium (Cs) to tungsten (W) was put into a hot press device and sintered under conditions of a vacuum atmosphere, a temperature of 950°C, and a pressure of 250 kgf/ ^cm2 to produce a cesium tungsten oxide sintered body. As a result of chemical analysis of the sintered body composition by ICP, the atomic ratio Cs/W of cesium (Cs) to tungsten (W) was 0.33. This oxide sintered body was ground by machining to a diameter of 153 mm and a thickness of 5 mm, and joined to a stainless steel backing plate using a metal indium brazing material to produce a cesium tungsten oxide sputtering target.
(Infrared reflective film laminate manufacturing process)
Next, the sputtering target was attached to a DC sputtering device (SBH2306 manufactured by ULVAC), and an infrared reflective film 22 was formed on a plate-shaped substrate 21 as shown in FIG. 2(A), thereby producing an infrared reflective film laminate 20.

The plate-shaped substrate 21 used was an ultra-thin glass sheet (G-Leaf, manufactured by Nippon Electric Glass Co., Ltd.) with a thickness of 30 μm.

The infrared reflective film 22 was formed under the following conditions. After the plate-shaped substrate 21 was set in the sputtering device, the chamber was evacuated. The ultimate vacuum level was 5×10 ⁻³ Pa or less, the atmosphere during film formation was an argon gas atmosphere, and the gas pressure was 0.6 Pa. The input power during film formation was 600 W DC, and a cesium tungsten oxide film, which is a composite tungsten oxide film serving as an infrared reflective film, was formed on the plate-shaped substrate 21.

The thickness of the formed infrared reflective film 22 was 100 nm.
(Heat treatment process)
The infrared reflective film laminate 20 including the infrared reflective film 22 was placed in a lamp heating furnace (HP-2-9 manufactured by Yonekura Seisakusho Co., Ltd.) and heat-treated in a nitrogen atmosphere at a temperature of 500° C. for 10 minutes. The infrared reflective film after the heat treatment step was chemically analyzed by ICP, and the Cs/W ratio indicating the atomic ratio of cesium (Cs) to tungsten (W) was 0.33. The composition of the composite tungsten oxide film, which is the formed infrared reflective film, is expressed _{as Cs0.33WOy} (2.2≦y≦3.0).
(Micronization process)
The infrared reflective film laminate 20 after the heat treatment step was cut into squares of 600 nm × 600 nm (aspect ratio a/c = 8.5) together with the ultra-thin glass plate as the plate-like substrate by a laser, as shown in Figure 2 (B) . In this way, infrared reflective film-containing particles 12 having an infrared reflective film 122 on a substrate 121 were produced.

The infrared reflective film is also cut so that the surface perpendicular to the film thickness direction of the infrared reflective film is a square with a side of 600 nm. Therefore, the longest part of the infrared reflective film in the film surface direction is the diagonal part of the square, and its length a is about 848.4 nm. Therefore, the aspect ratio a/c obtained by dividing the film thickness c by 100 nm is 8.5 as described above.
(Molding process)
As shown in FIG. 2C, 1 part by weight of the obtained infrared reflective film-containing particles 12, 71 parts by weight of polyvinyl butyral as a resin 11, and 28 parts by weight of triethylene glycol-di-2-ethyl butyrate as a plasticizer were mixed to prepare a mixture.

Next, as shown in FIG. 2(D), the mixture containing the infrared reflective film-containing particles 12 and the resin 11 was kneaded with a roll and formed into a sheet having a thickness of 0.76 mm to produce the infrared reflective film dispersion 10.

The prepared infrared reflective film dispersion was sandwiched between two clear glass substrates measuring 100 mm × 100 mm × approximately 2 mm in thickness, heated to 80°C for temporary bonding, and then placed in an autoclave at 140°C and 14 kg/ ^cm2 for permanent bonding to prepare a laminate including the infrared reflective film dispersion.

The reflectance profile of the laminate containing the infrared reflective film dispersion was measured using a spectrophotometer U-4100 manufactured by Hitachi, Ltd., and the result was as shown in Figure 4. In addition, the transmittance at a wavelength of 550 nm was measured and found to be 70%.
[Example 2]
(Infrared reflective film laminate manufacturing process)
The sputtering target of cesium tungsten oxide according to Example 1 was attached to a DC sputtering device, and an infrared reflective film 22 was formed on a plate-shaped substrate 21 in the same manner as in Example 1 to produce an infrared reflective film laminate 20. At this time, an ultra-thin glass plate (SCHOTT AS 87 eco manufactured by Schott Japan Co., Ltd.) having a thickness of 100 μm was used as the plate-shaped substrate 21. The thickness of the formed infrared reflective film 22 was 100 nm.
(Heat treatment process)
The infrared reflective film laminate 20 including the infrared reflective film 22 was placed in a xenon flash lamp annealing device (manufactured by Heraeus Corporation) and heat-treated using a xenon flash lamp in a nitrogen atmosphere. At this time, the distance between the laminate surface and the lamp was 15 mm, the flash time per flash was 3.3 milliseconds, the number of flashes during the heat treatment process was 1000, the frequency was 3 Hz, and the voltage was 400 V. As a result of chemically analyzing the infrared reflective film after the heat treatment process by ICP, Cs/W, which indicates the atomic ratio of cesium (Cs) to tungsten (W), was 0.33. The composition of the composite tungsten oxide film, which is the infrared reflective film formed, is expressed as Cs _0.33 WO _y (2.2≦y≦3.0).
Thereafter, the micronization step and molding step were carried out in the same manner as in Example 1 to produce an infrared reflective film dispersion 10, and the reflectance at a wavelength of 1,400 nm was measured to be 51%, and the transmittance at a wavelength of 550 nm was measured to be 71%.
[Reference Example 1]
The reflectance profile of the infrared reflective film laminate obtained after the heat treatment step of Example 1 was measured in the same manner as in Example 1, and the result was as shown in Fig. 4. In addition, the transmittance at a wavelength of 550 nm was measured and found to be 74%.

As is clear from the results shown in Figure 4, it was confirmed that the infrared reflective film dispersion, which is a dispersion of infrared reflective film-containing particles obtained by micronizing the infrared reflective film laminate, has sufficient infrared reflective properties equivalent to those of the infrared reflective film before micronization.

And unlike an infrared reflective film, which is a single film, there are no size or shape restrictions on the infrared reflective film dispersion, and the size and shape can be selected as desired. For this reason, it was confirmed that an infrared reflective film dispersion capable of reflecting infrared rays can be manufactured with good productivity and in the desired size and shape.

REFERENCE SIGNS LIST 10 Infrared reflective film dispersion 11 Resin 12 Infrared reflective film-containing particles 121 Substrate 20, 30 Infrared reflective film laminate 21, 313 Plate-shaped substrate 22, 32, 122 Infrared reflective film 31 Film-forming substrate 311 Support substrate 312 Release layer

Claims (7)

A resin and infrared reflective film-containing particles disposed in the resin,
The infrared reflective film-containing particle has a substrate and an infrared reflective film disposed on the substrate and containing one or more selected from a metal and an oxide,
The infrared reflective film contains a composite tungsten oxide,
The composite tungsten oxide is an infrared reflective film dispersion represented by the general formula MxWOy ₍ wherein _M is one or more elements selected from Cs, Rb, K, Tl, In, Ba, Li, Ca, Sr, Fe, Sn, Al, Cu, and Na, and 0.001≦x≦1, 2.2≦y≦3.0). 2. The infrared reflective film dispersion according to claim 1 , wherein an aspect ratio a/c, which is a ratio of a length a of the longest portion in a film surface direction of the infrared reflective film to a film thickness c, is 3 or more. an infrared reflective film laminate preparation step of forming an infrared reflective film containing one or more selected from metals and oxides on a plate-like substrate to prepare an infrared reflective film laminate;
a micronization step of micronizing the infrared reflective film laminate to form infrared reflective film-containing particles in which the infrared reflective film is disposed on the micronized plate-like substrate;
a molding step of kneading the infrared reflective film-containing particles with a resin and molding the mixture ,
The infrared reflective film contains a composite tungsten oxide,
The composite tungsten oxide is represented by the general formula MxWOy _{( wherein} M is one or more elements selected from Cs, Rb, K, Tl, In, Ba, Li, Ca, Sr, Fe, Sn, Al, Cu, and Na, and 0.001≦x≦1, 2.2≦y≦3.0). A film-forming process of forming an infrared reflective film containing one or more selected from metals and oxides on a plate-shaped substrate having a support substrate, a release layer, and a plate-shaped substrate laminated in this order;
a peeling step of dissolving the release layer and peeling off an infrared reflective film laminate having the infrared reflective film formed on the plate-shaped substrate from the supporting substrate;
a micronization step of micronizing the infrared reflective film laminate to form infrared reflective film-containing particles in which the infrared reflective film is disposed on the micronized plate-like substrate;
A method for producing an infrared reflective film dispersion, comprising: kneading the infrared reflective film-containing particles with a resin and molding the mixture. The infrared reflective film is
The method for producing an infrared reflective film dispersion according to claim 4, which contains at least one selected from the group consisting of silver, gold, aluminum, platinum, rhodium, copper, nickel, zinc oxide, indium oxide, tin-doped indium oxide, titanium oxide, and composite tungsten oxide. The infrared reflective film contains a composite tungsten oxide,
The method for producing an infrared reflective film dispersion according to claim 4 or 5, wherein the composite tungsten oxide is _represented by a general formula _MxWOy (wherein M is one or more elements selected from Cs, Rb, K, Tl, In, Ba, Li, Ca, Sr, Fe, Sn, Al, Cu, and Na, and 0.001≦x≦ 1 , 2.2≦y≦3.0). The aspect ratio a/c, which is the ratio of the length a of the longest portion of the infrared reflective film in the film surface direction to the film thickness c, is set to 3 or more.
The method for producing an infrared reflective film dispersion according to claim 3 , wherein the infrared reflective film laminate is micronized in the micronization step.

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