JP7003859B2 - Manufacturing method of surface-coated near-infrared shielding fine particles and surface-coated near-infrared shielding fine particles - Google Patents

Description

The present invention relates to near-infrared shielding fine particles having high transmission characteristics in the visible wavelength region and high absorption characteristics in the near-infrared wavelength region, and in particular, atomic layer deposition (ALD) using the atomic layer deposition (ALD) method. The present invention relates to surface-coated near-infrared shielding fine particles having a coating layer without pinholes formed on the surface of the near-infrared shielding fine particles by an apparatus to improve the weather resistance, and a method for producing the same.

Of the sun's rays, near-infrared rays (heat rays) in the long wavelength region are light in the wavelength region that the human body perceives as heat energy, and cause a rise in temperature inside the room and the vehicle. On the other hand, ultraviolet rays in the short wavelength region adversely affect the human body such as sunburn, spots, freckles, carcinogenesis, and visual impairment, resulting in deterioration of mechanical strength of articles, deterioration of appearance such as fading, deterioration of foods, and color tones of printed matter. It causes a decrease and the like.

Of these unnecessary near-infrared rays (heat rays) and harmful ultraviolet rays, in order to shield near-infrared rays (heat rays), a solar-shielding film that shields near-infrared rays is formed on the base material to provide a solar-shielding function. Transparent substrates such as glass substrates, plastic plates, and films are used. Conventionally, as the above-mentioned solar-shielding film, a solar-shielding film using a thin film of gold, silver, copper, aluminum or the like having a large amount of conduction electrons as a solar-shielding material has been used.

On the other hand, a method has also been proposed in which a coating liquid containing a solar shielding material is applied onto a transparent substrate to form a solar shielding film, and a transparent substrate having a solar shielding function can be produced easily and at low cost. ..

For example, Patent Document 1 states that the hexaboride has a large amount of free electrons, and that the hexaboride is made into fine particles and highly dispersed to have a maximum transmittance in the visible light region and visible light. It is disclosed that strong plasma reflection is exhibited in the near-infrared region close to the region to have a minimum transmittance.

Further, Patent Document 2 is a hexaboride particle dispersion in which a dispersion in which hexaboride fine particles are dispersed in a solid medium such as resin or glass constitutes a film or board having a thickness of 0.1 μm to 50 mm. Is disclosed.

However, it is known that the surface of hexaboride fine particles is decomposed and deteriorated (changes to oxides and hydroxides) due to water vapor and water in the air. The ratio is large. Due to its characteristics, solar shielding materials are basically used outdoors and are often required to have high weather resistance. Then, in some optical members (films, resin sheets, etc.) containing hexaboride fine particles, water vapor and moisture in the air gradually permeate into the matrix and decompose the surface of the hexaboride particles 200. There is a problem that the transmittance in the ~ 2600 nm region increases with time, and the solar shading performance gradually deteriorates.

To solve this problem, Patent Document 2 proposes a method of coating the surface of hexaboride particles with a surface treatment agent such as alkoxysilane to improve the water resistance of the hexaboride particles.

Further, Patent Document 3 proposes a method for producing surface-coated hexaboride particles in which a coating layer of silica is formed on the surface of hexaboride particles using a hydrolyzable silane compound. That is, this production method has an organic metal compound (this compound has a function of dispersing hexavalent particles and a function of promoting polymerization of the following hydrolyzable silane compound) in a dispersion liquid in which hexaborized particles are dispersed in an organic solvent. ) Is added and the organic metal compound is adsorbed on the surface of the hexaboride particles, and then water and the above-mentioned hydrolyzable silane compound are added to the surface of the hexaboride particles on which the organic metal compound is adsorbed. Cover with compound. Next, after removing the solvent from the dispersion of the hexaboride particles coated with the hydrolyzable silane compound, the hexaboride particles were heated and fired under the conditions of the decomposition temperature of the organic metal compound or higher, and further, the obtained powder was obtained. It was a method of producing surface-coated hexaboride particles in which a silica-coated layer was formed by crushing the state.

However, in the method of Patent Document 2 using a surface treatment agent such as alkoxysilane, when the average primary particle diameter of the hexaboride particles becomes as fine as 200 nm or less, the concentration of alkoxysilane or the like is increased together with the hexaboride fine particles. When the value is high, the hexaboride fine particles are likely to aggregate in the hydrolysis / polycondensation reaction process, and the surface treatment is performed on the aggregate in which the hexaboride fine particles are aggregated. Therefore, after the surface treatment, a mechanical dispersion treatment such as a medium stirring mill is required, and when the dispersion treatment is performed, the silica coating layer is formed when the fine particles forming the cluster structure are dissociated via the silica component. Hexaboride fine particles with exposed surfaces were formed, and it was difficult to impart sufficient transparency and water resistance to various substrates. Further, although the method of Patent Document 3 for forming the silica coating layer is improved as compared with Patent Document 2, the above-mentioned problems have not been solved yet.

On the other hand, Patent Document 4 proposes a combined structure for solar radiation shielding to which tungsten oxide fine particles having a solar radiation shielding function or composite tungsten oxide fine particles are applied.

That is, in the above structure proposed in Patent Document 4, an intermediate layer containing fine particles having a solar shielding function is placed between two laminated plates selected from flat glass, plastic, and plastic containing fine particles having a solar shielding function. It is a laminated structure for shielding solar radiation that is intervened.
The fine particles having a solar radiation shielding function are tungsten oxide fine particles represented by the general formula WyOz (where W is tungsten, O is oxygen, 2.0 <z / y <3.0), and / or the general formula MxWyOz. (However, M is H, He, alkali metal, alkaline earth metal, rare earth element, Mg, Zr, Cr, Mn, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au. , Zn, Cd, Al, Ga, In, Tl, Si, Ge, Sn, Pb, Sb, B, F, P, S, Se, Br, Te, Ti, Nb, V, Mo, Ta, Re One or more elements selected from, W is tungsten, O is oxygen, and composite tungsten oxide fine particles represented by 0.001 ≦ x / y ≦ 1, 2.0 <z / y ≦ 3.0). It is characterized by being composed.

However, as described in Non-Patent Document 1, it is known that the composite tungsten oxide fine particles have the following deterioration phenomenon.
(1) Coloring phenomenon in which H ⁺ enters the composite tungsten oxide fine particles from the resin around the composite tungsten oxide fine particles and is colored by irradiation with ultraviolet rays (2) Moisture around the composite tungsten oxide fine particles (Cs _0.33 WO ₃ ) Is an oxidation phenomenon that weakens the absorption of Cs plasmon on the surface of composite tungsten oxide fine particles.

Therefore, in order to suppress the deterioration phenomenon of the composite tungsten oxide fine particles, Patent Document 5 adds the above-mentioned organic metal compound to the dispersion liquid of the composite tungsten oxide fine particles dispersed in the organic solvent, as in Patent Document 3. Then, the silane compound was added while stirring the mixed solution, the silane compound and the organic metal compound were coated on the surface of the composite tungsten fine particles, and then the mixed solution was dried to dryness to obtain the solidified product. We propose infrared shielding fine particles that have been crushed and coated with a silane compound and / or an organic metal compound.

However, as in Patent Document 3, although the above-mentioned problem (deterioration phenomenon of composite tungsten oxide fine particles) is improved, it has not been solved yet.

As described above, in the boride fine particles and the composite tungsten oxide fine particles having a solar radiation shielding function, decomposition deterioration due to water vapor in the air, characteristic deterioration phenomenon due to ultraviolet irradiation, etc. have been found, and these deteriorations have been found. A method capable of effectively suppressing the phenomenon has been desired.

Japanese Unexamined Patent Publication No. 2000-072484 (see paragraph 0024-0025) JP-A-2003-277045 (see claim 11, paragraph 0005-0006). JP-A-2007-308341 (see claim 1) WO2005 / 0876880 A1 publication (see claim 1) Japanese Unexamined Patent Publication No. 2008-291109 (see claim 4) Japanese Unexamined Patent Publication No. 2002-314072

Kenji Adachi et al, J. Appl. Phys., 114, 194304 (2013) Riikka L. Puurunen, J. Appl. Phys., 97,121301 (2005)

The present invention has been made by paying attention to such a problem, and the subject thereof is a coating layer having no pinhole on the surface of near-infrared shielding fine particles selected from borohydride fine particles or composite tungsten oxide fine particles. To provide a method for producing surface-coated near-infrared shielding fine particles capable of suppressing deterioration phenomena caused by water vapor or ultraviolet irradiation by the coating layer, and also to provide surface-coated near-infrared shielding fine particles obtained by this production method. There is something in it.

Therefore, in order to solve the above-mentioned problems, the present inventor pays attention to the atomic layer deposition (ALD) method described in Non-Patent Document 2, and also pays attention to the ALD method for forming the above-mentioned coating layer without pinholes. I tried to adopt. That is, in the ALD method, the raw material gas containing the elements constituting the atomic layer (molecular layer) is alternately introduced into the vacuum device and adsorbed on the outermost surface of the fine particles of the film to be deposited contained in the vacuum device. This is a method in which the thickness of the coating layer can be controlled at the atomic layer level by depositing monatomic (monatomic) layers at a time by the reaction between the molecules and the raw material gas to be introduced next. When the ALD method was applied to the formation of the coating layer in the near-infrared shielding fine particles, the film formation speed was slower than that of the sputtering method, but the raw material gas spread to every detail, so that a thin film without pinholes could be formed, and the film was formed. It was confirmed that a thin film can be formed even in minute gaps without being affected by the unevenness of the film surface. The present invention has been completed based on such technical studies and analysis.

That is, the first invention according to the present invention is
In a method for producing surface-coated near-infrared shielding fine particles, which comprises a near-infrared shielding fine particle and a coating layer covering the surface of the near-infrared shielding fine particle.
One or more types of near-infrared shielding fine particles having an average particle size of 10 to 500 nm selected from composite tungsten oxide fine particles and borohydride fine particles, and Al ₂ O _3, SiO ₂ , SiO Al, SiC, SiOC, and SiC N are selected and close to each other. The surface-coated near-infrared shielding fine particles are composed of a coating layer composed of one or more atomic layers that coat the surface of the infrared-shielding fine particles.
The atomic layer deposition (ALD) apparatus using the atomic layer deposition (ALD) method, in which one atomic layer is formed in one cycle consisting of a first reaction gas adsorption step and an exhaust step and a second reaction gas reaction step and an exhaust step, is used. It is characterized in that four or more atomic layers are formed to form a coating layer composed of one or more atomic layers.
Further, the second invention according to the present invention is
In a method for producing surface-coated near-infrared shielding fine particles composed of a near-infrared shielding fine particle and a coating layer covering the surface of the near-infrared shielding fine particle.
One or more kinds of near-infrared shielding fine particles having an average particle size of 10 to 500 nm selected from composite tungsten oxide fine particles and borohydride fine particles, and Al ₂ O _3, SiO ₂ , SiO Al, SiC, SiOC, and SiC N are selected and close to each other. A first coating layer consisting of one or more atomic layers covering the surface of infrared shielding fine particles, and a second consisting of one or more atomic layers selected from Al ₂ O _{3 and} SiO ₂ and covering the surface of the first coating layer. The coating layer constitutes the surface-coated near-infrared shielding fine particles.
The atomic layer deposition (ALD) apparatus using the atomic layer deposition (ALD) method, in which one atomic layer is formed in one cycle consisting of a first reaction gas adsorption step and an exhaust step and a second reaction gas reaction step and an exhaust step, is used. One atomic layer is formed into four or more layers to form a first coating layer composed of one or more atomic layers, and at the same time.
It is characterized in that one or more atomic layers are formed by an atomic layer deposition (ALD) apparatus using the atomic layer deposition (ALD) method to form a second coating layer composed of one or more atomic layers. It is something to do.

Next, the third invention according to the present invention is
In the method for producing surface-coated near-infrared shielding fine particles according to the first invention or the second invention.
A plurality of vacuum chambers having an exhaust mechanism are arranged in vertical direction via an opening / closing valve for moving fine particles that controls the movement of near-infrared shielding fine particles, and the first reaction gas adsorption step and the second reaction gas reaction are described above. It is characterized in that the coating layer or the first coating layer and the second coating layer are formed by using an atomic layer deposition (ALD) device provided with a reaction gas introduction mechanism in at least a pair of vacuum chambers in which the process is performed.
The fourth invention is
In the method for producing surface-coated near-infrared shielding fine particles according to the third invention.
The plurality of vacuum chambers chemically apply the first reaction gas to the surface of the first vacuum chamber into which a certain amount of near-infrared shielding fine particles are introduced and the surface of the fine particles introduced from the first vacuum chamber via an opening / closing valve for moving the fine particles. The fine particles that chemically adsorbed the first reaction gas from the second vacuum chamber via the second vacuum chamber to be adsorbed and the opening / closing valve for moving the fine particles were introduced and by-produced with the excess first reaction gas that flowed from the second vacuum chamber. One atom by reacting the first reaction gas and the second reaction gas chemically adsorbed on the surface of the fine particles introduced from the third vacuum chamber through the third vacuum chamber for exhausting the object and the opening / closing valve for moving the fine particles. The fine particles having formed a single atomic layer were introduced from the 4th vacuum chamber via the 4th vacuum chamber forming the layer and the opening / closing valve for moving the fine particles, and the excess second reaction gas and by-production flowing from the 4th vacuum chamber were introduced. It is composed of a fifth vacuum chamber that exhausts things, and the first vacuum chamber at the top is provided with an on-off valve for introducing fine particles that introduces a certain amount of near-infrared shielding fine particles, and the fifth vacuum at the bottom. The atomic layer deposition (ALD) device described in the third invention is provided by the atomic layer deposition (ALD) device provided with an open / close valve for discharging fine particles in the chamber, which discharges near-infrared shielding fine particles having an atomic layer formed therein. Characterized by being configured
Moreover, the fifth invention is
In the method for producing surface-coated near-infrared shielding fine particles according to the third invention or the fourth invention.
A transport vacuum chamber is provided in communication with the lowermost vacuum chamber provided with a fine particle discharge open / close valve for discharging near-infrared shielding fine particles on which an atomic layer is formed via the fine particle discharge open / close valve, and the above-mentioned transport is performed. The vacuum chamber is provided in communication with the uppermost vacuum chamber via an opening / closing valve for introducing fine particles, and also transports near-infrared shielding fine particles having an atomic layer formed by a transport mechanism in the transport vacuum chamber. It is characterized in that the atomic layer deposition (ALD) apparatus described in the fourth invention is configured by the atomic layer deposition (ALD) apparatus introduced into the uppermost vacuum chamber.

Furthermore, the sixth invention according to the present invention is
In the method for producing surface-coated near-infrared shielding fine particles according to the first invention or the second invention.
The composite tungsten oxide fine particles are the general formula MxWyOz (M is H, He, alkali metal, alkaline earth metal, rare earth element, Mg, Zr, Cr, Mn, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Tl, Si, Ge, Sn, Pb, Sb, B, F, P, S, Se, Br, Te, Ti, Nb, Represents at least one element selected from the group consisting of V, Mo, Ta, Re, Be, Hf, Os, Bi and I, where x, y, z are 0.01≤x≤1, 0.001. It is composed of composite tungsten oxide fine particles represented by ≦ x / y ≦ 1, 2.2 ≦ z / y ≦ 3.0).
The boride fine particles are composed of the general formula XBm (where X is Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Sr, Ca). At least one kind of metal element selected from the group, m is a numerical value indicating the amount of boron in the above general formula, and is composed of boride fine particles represented by 4.0 ≦ m ≦ 6.2). Characterized by that
The seventh invention is
In the surface-coated near-infrared shielding fine particles composed of the near-infrared shielding fine particles and the coating layer covering the surface of the near-infrared shielding fine particles.
It is characterized by being obtained by the method for producing surface-coated near-infrared shielding fine particles according to any one of the first invention to the sixth invention.

According to the first method of invention according to the present invention, atomic layer deposition (ALD) in which one atomic layer is formed in one cycle consisting of a first reaction gas adsorption step and an exhaust step and a second reaction gas reaction step and an exhaust step. Select from Al ₂ O _3, SiO ₂ , SiO Al, SiC, SiOC, SiC N on the surface of near-infrared shielding fine particles (composite tungsten oxide fine particles and / or borohydride fine particles) by an atomic layer deposition (ALD) device using the method. Forming a coating layer consisting of one or more atomic layers
Further, according to the second method of the present invention, atomic layer deposition (in which one atomic layer is formed in one cycle consisting of a first reaction gas adsorption step and an exhaust step and a second reaction gas reaction step and an exhaust step) Al ₂ O _3, SiO ₂ , SiO Al, SiC, SiOC, SiC N An atomic layer deposition (ALD) device using the atomic layer deposition (ALD) method described above forms an first coating layer consisting of one or more atomic layers selected from the above, and Al ₂ O is applied to the surface of the first coating layer. _3. A second coating layer composed of one or more atomic layers selected from SiO ₂ is formed to produce surface-coated near-infrared shielding fine particles.

Since the above-mentioned coating layer or the first coating layer and the second coating layer formed by the atomic layer deposition (ALD) apparatus are each composed of an atomic layer without pinholes, they are conventionally caused by water vapor, ultraviolet irradiation, or the like. Therefore, it has the effect of effectively suppressing the decomposition deterioration and characteristic deterioration phenomenon that have occurred in the boride fine particles and the composite tungsten oxide fine particles.

Schematic diagram of the crystal structure of the composite tungsten oxide fine particles. FIG. 3 is a structural sectional view of a surface-coated near-infrared ray-shielding fine particle according to the present invention, which is composed of a near-infrared ray-shielding fine particle 30 and a coating layer 31 composed of one kind of atomic layer (4 or more layers) covering the surface of the fine particle 30. A first coating layer 41 composed of a near-infrared shielding fine particle 40, one kind of atomic layer (four or more layers) covering the surface of the fine particles 40, and one kind of atomic layer (1) covering the surface of the first coating layer 41. The block sectional view of the surface-coated near-infrared shielding fine particles according to the present invention composed of the second coating layer 42 composed of (layers and above). The first composed of the near-infrared shielding fine particles 50 and two types of atomic layers 51a and 51b covering the surface of the fine particles 50 (the total number of atomic layers of the atomic layer 51a and the number of atomic layers of the atomic layer 51b is 4 or more). Structural sectional view of the surface-coated near-infrared shielding fine particles according to the present invention, which is composed of a coating layer 51 and a second coating layer 52 composed of one kind of atomic layer (one or more layers) covering the surface of the first coating layer. .. FIG. 5 is an explanatory diagram showing the configuration of an atomic layer deposition (ALD) device used in the method of the present invention in which the first vacuum chamber to the fifth vacuum chamber are arranged in vertical communication via an on-off valve for moving fine particles. (A) shows a state in which near-infrared shielding fine particles are present in the first vacuum chamber, the third vacuum chamber, and the fifth vacuum chamber, and FIG. 5 (b) shows the second vacuum chamber and the fourth vacuum chamber. It shows the state where the near-infrared shielding fine particles are present inside.

Hereinafter, embodiments of the present invention will be described in detail.

The present invention relates to a method for producing surface-coated near-infrared shielding fine particles composed of a near-infrared shielding fine particle and a coating layer covering the surface of the near-infrared shielding fine particle.

The method for producing surface-coated near-infrared shielding fine particles according to the first embodiment of the present invention is
One or more types of near-infrared shielding fine particles having an average particle size of 10 to 500 nm selected from composite tungsten oxide fine particles and borohydride fine particles, and Al ₂ O _3, SiO ₂ , SiO Al, SiC, SiOC, and SiC N are selected and close to each other. The surface-coated near-infrared shielding fine particles are composed of a coating layer composed of one or more atomic layers that coat the surface of the infrared-shielding fine particles.
The atomic layer deposition (ALD) apparatus using the atomic layer deposition (ALD) method, in which one atomic layer is formed in one cycle consisting of a first reaction gas adsorption step and an exhaust step and a second reaction gas reaction step and an exhaust step, is used. It is characterized in that four or more atomic layers are formed to form a coating layer composed of one or more atomic layers.
The method for producing surface-coated near-infrared shielding fine particles according to the second embodiment of the present invention is as follows.
One or more kinds of near-infrared shielding fine particles having an average particle size of 10 to 500 nm selected from composite tungsten oxide fine particles and borohydride fine particles, and Al ₂ O _3, SiO ₂ , SiO Al, SiC, SiOC, and SiC N are selected and close to each other. A first coating layer consisting of one or more atomic layers covering the surface of infrared shielding fine particles, and a second consisting of one or more atomic layers selected from Al ₂ O _{3 and} SiO ₂ and covering the surface of the first coating layer. The surface-coated near-infrared shielding fine particles are composed of the coating layer.
The atomic layer deposition (ALD) apparatus using the atomic layer deposition (ALD) method, in which one atomic layer is formed in one cycle consisting of a first reaction gas adsorption step and an exhaust step and a second reaction gas reaction step and an exhaust step, is used. One atomic layer is formed into four or more layers to form a first coating layer composed of one or more atomic layers, and at the same time.
It is characterized in that one or more atomic layers are formed by an atomic layer deposition (ALD) apparatus using the atomic layer deposition (ALD) method to form a second coating layer composed of one or more atomic layers. It is something to do.

Below, 1. Near-infrared shielding fine particles to be the film to be deposited 2. 2. Coating film (membrane type) and its film material (reaction gas) obtained by the atomic layer deposition method. Structure of the coating layer, 4. Atomic layer deposition equipment (1) Atomic layer deposition (ALD) method, (2) Atomic layer deposition (ALD) equipment used in the method of the present invention, and (3) Atomic layer deposition (ALD) equipment. The method for producing the surface-coated near-infrared shielding fine particles used will be described in order.

1. 1. Near-infrared shielding fine particles to be the film to be deposited
As the "near-infrared shielding fine particles" constituting the surface-coated near-infrared shielding fine particles of the present invention, composite tungsten oxide fine particles and boride fine particles are used.

The composite tungsten oxide fine particles and the boride fine particles may be mixed and applied, or may be individually applied without being mixed.

(1) Composite tungsten oxide fine particles The composite tungsten oxide fine particles are of the general formula MxWyOz (M is H, He, alkali metal, alkaline earth metal, rare earth element, Mg, Zr, Cr, Mn, Fe, Ru, Co. , Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Tl, Si, Ge, Sn, Pb, Sb, B, F, P, S, Se, Br , Te, Ti, Nb, V, Mo, Ta, Re, Be, Hf, Os, Bi and I represent at least one element selected from the group, x, y, z is 0.01 ≦ It is composed of composite tungsten oxide fine particles represented by (satisfying x ≦ 1, 0.001 ≦ x / y ≦ 1, 2.2 ≦ z / y ≦ 3.0), and has an average particle size of 10 nm to 500 nm. It is characterized by being.

In general, it is known that a material containing free electrons exhibits a reflection absorption response to electromagnetic waves around a region in a sun ray having a wavelength of 200 nm to 2600 nm due to plasma oscillation. It is known that when the powder of such a substance is made into fine particles having a particle size smaller than the wavelength of light, geometric scattering in the visible light region (380 nm to 780 nm) is reduced and transparency in the visible light region can be obtained. .. In the present specification, "transparency" is used in the sense that there is little scattering and high transparency with respect to light in the visible light region.

In general, since there are no effective free electrons in WO ₃ , the absorption and reflection characteristics in the near infrared region are small, and it is not effective as an infrared shielding material.

On the other hand, WO ₃ having an oxygen deficiency and so-called tungsten bronze obtained by adding a positive element such as Na to WO ₃ are known to be conductive materials and materials having free electrons. Analysis of these single crystals of materials with free electrons suggests the response of free electrons to light in the infrared region.

It has been found that there is a particularly effective range as an infrared shielding material in a specific part of the composition range of tungsten and oxygen, and a tungsten oxide that is transparent in the visible light region and has absorption in the near infrared region. And / or, an infrared shielding material fine particle dispersion in which composite tungsten oxide fine particles are dispersed in a medium is produced.

When the above-mentioned general formula MxWyOz (where M is the M element, W is tungsten, O is oxygen) is described as an infrared shielding material in which control of the amount of oxygen and addition of an element that generates free electrons are used in combination. , 0.01 ≦ x ≦ 1, 0.001 ≦ x / y ≦ 1, 2.2 ≦ z / y ≦ 3.0, an infrared shielding material that satisfies the relationship is desirable.

First, the value of x / y indicating the amount of the element M added will be described.

If the value of x / y is larger than 0.001, a sufficient amount of free electrons are generated and the desired infrared shielding effect can be obtained. As the amount of the element M added increases, the supply amount of free electrons increases and the infrared shielding efficiency also increases, but the effect is saturated when the value of x / y is about 1. Further, when the value of x / y is smaller than 1, it is preferable because it is possible to avoid the formation of an impurity phase in the infrared shielding material.

The element M is H, He, alkali metal, alkaline earth metal, rare earth element, Mg, Zr, Cr, Mn, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au. , Zn, Cd, Al, Ga, In, Tl, Si, Ge, Sn, Pb, Sb, B, F, P, S, Se, Br, Te, Ti, Nb, V, Mo, Ta, Re, Be , Hf, Os, Bi, and I are preferably one or more.

Here, from the viewpoint of stability in the MxWyOz to which the element M is added, the element M is an alkali metal, an alkaline earth metal, a rare earth element, Mg, Zr, Cr, Mn, Fe, Ru, Co, Rh. , Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Tl, Si, Ge, Sn, Pb, Sb, B, F, P, S, Se, Br, Te , Ti, Nb, V, Mo, Ta, Re, more preferably one or more elements, and from the viewpoint of improving the optical properties and weather resistance as an infrared shielding material, the above. More preferably, the element M belongs to an alkaline earth metal element, a transition metal element, a 4B group element, and a 5B group element.

Next, the value of z / y indicating the control of the amount of oxygen will be described. Regarding the value of z / y, in addition to the same mechanism as the infrared shielding material expressed in WyOz of Patent Document 4 working in the infrared shielding material expressed in MxWyOz, at z / y = 3.0. However, since there is a supply of free electrons depending on the amount of the element M added, 2.2 ≦ z / y ≦ 3.0 is preferable, and 2.45 ≦ z / y ≦ 3.0 is more preferable.

Further, when the composite tungsten oxide fine particles have a hexagonal crystal structure, the transmission of the fine particles in the visible light region is improved, and the absorption in the near infrared region is improved. This will be described with reference to FIG. 1, which is a schematic plan view of the crystal structure of the hexagonal crystal. In FIG. 1, six octahedrons formed by WO ₆ units indicated by reference numeral 1 are assembled to form a hexagonal void, and an element M indicated by reference numeral 2 is arranged in the void to form one. Units are formed, and a large number of these one unit are assembled to form a hexagonal crystal structure.

In order to obtain the effect of improving the transmission in the visible light region and improving the absorption in the near infrared region, the unit structure described in FIG. 1 (an octahedron formed in WO ₆ units) is contained in the composite tungsten oxide fine particles. A hexagonal void is formed by gathering six of them, and the structure in which the element M is arranged in the void) may be contained, and the composite tungsten oxide fine particles are amorphous even if they are crystalline. It doesn't matter.

When the cation of the element M is added to the hexagonal void and exists, the transmission in the visible light region is improved and the absorption in the near infrared region is improved. Here, in general, the hexagonal crystal is formed when the element M having a large ionic radius is added, and specifically, the hexagonal crystal is formed when Cs, K, Rb, Tl, In, Ba, Sn are added. Easy to form. Of course, even with elements other than these, the above-mentioned element M may be present in the hexagonal voids formed in WO ₆ units, and the present invention is not limited to the above-mentioned elements.

When the composite tungsten oxide fine particles having a hexagonal crystal structure have a uniform crystal structure, the amount of the additive element M added is preferably 0.2 or more and 0.5 or less in terms of x / y, more preferably 0. It is .33. When the value of x / y becomes 0.33, it is considered that the above-mentioned element M is arranged in all the hexagonal voids.

In addition to hexagonal crystals, tetragonal and cubic tungsten bronze are also effective as infrared shielding materials. The absorption position in the near-infrared region tends to change depending on the crystal structure, and the absorption position tends to move to the long wavelength side in the order of cubic <tetragonal <hexagonal. Along with this, the absorption in the visible light region is less in the order of hexagonal crystal, tetragonal crystal, and cubic crystal, so that light in the visible light region is transmitted more and light in the infrared region is shielded. For applications, it is preferable to use hexagonal tungsten bronze. However, the tendency of the optical characteristics described here is only a rough tendency and changes depending on the type of added element, the added amount, and the amount of oxygen, and the present invention is not limited to this.

Since the infrared shielding material containing the composite tungsten oxide fine particles largely absorbs light in the near infrared region, particularly in the vicinity of 1000 nm, the transmitted color tone of the material often changes from bluish to green.

Further, the average particle size of the near-infrared shielding fine particles needs to be 10 nm to 500 nm, and can be appropriately selected from the above range depending on the purpose of use. First, when used for applications that maintain transparency, it is preferable to have a particle size of 500 nm or less. This is because particles smaller than 500 nm do not completely block light due to scattering, and can maintain visibility in the visible light region and at the same time efficiently maintain transparency. In particular, when the transparency in the visible light region is emphasized, it is preferable to further consider scattering by particles.

When the reduction of scattering by the particles is emphasized, the particle diameter is preferably 200 nm or less, preferably 100 nm or less. The reason for this is that if the particle size of the particles is small, the scattering of light in the visible light region of 400 nm to 780 nm due to geometric scattering or Mie scattering is reduced, and as a result, the infrared shielding material becomes like frosted glass and is clear. This is because it is possible to avoid loss of transparency. That is, when the particle size is 200 nm or less, the geometrical scattering or Mie scattering is reduced, and a Rayleigh scattering region is formed. This is because in the Rayleigh scattering region, the scattered light intensity is proportional to the sixth power of the particle size, so that scattering is reduced and transparency is improved as the particle size decreases. Further, when the particle size is 100 nm or less, the scattered light becomes very small, which is preferable. From the viewpoint of avoiding light scattering, it is preferable that the particle size is small.

(2) Boride fine particles Next, the boride fine particles are of the general formula XBm (where X is Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb. , Lu, Sr, Ca, at least one kind of metal element selected from the group, m is a numerical value indicating the amount of boron in the above general formula, and is represented by 4.0≤m≤6.2). It is composed of fine boride fine particles, and is characterized in that the average particle size of the fine particles is 10 nm to 500 nm.

The near-infrared shielding fine particles are preferably 4.0 ≦ m ≦ 6.2 in the above-mentioned general formula XBm. That is, as the boride fine particles, usually, the powder containing the boride fine particles is actually a mixture of XB ₄ , XB ₆ , XB ₁₂ , and the like. For example, in the case of 6-boride, which is a typical boride fine particle, even if it is determined from the result of X-ray diffraction that it is a single phase, it is actually 5.8 <m <6.2, which is a very small amount. It is considered to contain other phases. Here, when m ≧ 4, the generation of XB, XB ₂ , etc. is suppressed, and the reason is unknown, but the infrared absorption characteristic is improved. On the other hand, when m <6.2, the generation of boron oxide particles other than the boride fine particles is suppressed. Since the boron oxide particles are hygroscopic, if the boron oxide particles are mixed in the boride powder, the moisture resistance of the boride powder is lowered and the near-infrared absorption characteristics are significantly deteriorated with time. Therefore, it is preferable to suppress the generation of boron oxide particles by setting m <6.2.

Among the above borides, it is preferable that XB ₄ and XB ₆ are the main constituents, and a part of XB ₁₂ may be contained. Here, m indicates the atomic number ratio of B to one atom of the X element by chemically analyzing the obtained powder containing the borohydride fine particles.

In the following description, 6 borides in the case of m = 6 as borides will be described as an example.

The 6 borides used in the present invention include LaB ₆ , CeB ₆ , PrB ₆ , NdB ₆ , SmB ₆ , EuB ₆ , GdB ₆ , TbB ₆ , DyB ₆ , HoB ₆ , ErB ₆ , TmB ₆ , and YbB ₆ . , LuB ₆ , SrB ₆ , CaB ₆ and YB ₆ .

It is preferable that the surface of the 6-boride fine particles used in the present invention is not oxidized, but usually the surface is slightly oxidized, and the surface is oxidized to some extent in the fine particle dispersion step. Inevitable. However, even in that case, there is no change in the effectiveness of exhibiting the near-infrared absorption effect. Further, these fine particles have a larger near-infrared absorption effect as the crystal perfection is higher, but even if the crystallinity is low and a broad diffraction peak is generated by X-ray diffraction, the inside of the fine particles is formed. If the basic bond has a cubic CaB ₆ type structure, it exhibits a near-infrared absorption effect. In addition, since the 6-boride fine particles are inorganic substances, they have excellent weather resistance.

These 6-borified fine particles are powders such as dark bluish purple and green, but the particle size is sufficiently smaller than that of the visible light wavelength, and the fine particles having this small particle size are placed on the surface and / or inside of the fiber. In the dispersed state, visible light transmission occurs, but the infrared absorption ability can be sufficiently strongly maintained. This is because the amount of free electrons in the 6 borohydride particles is large, and the absorption energy of plasmon absorption and interband indirect transition by the free electrons inside and on the surface of the particles is just in the vicinity of visible to near-infrared light. It is considered that this is because the heat rays in this wavelength region are selectively reflected and absorbed. According to the experiment, in the film in which these 6 boride fine particles are sufficiently finely and uniformly dispersed, the transmittance has a maximum value in the wavelength range of 400 to 700 nm and a minimum value in the wavelength range of 700 to 1800 nm. It has been found. Therefore, even in a dispersion containing the 6-boride fine particles on the surface and / or inside of the transparent substrate, wavelength characteristics having the same transmittance can be obtained.

Here, considering that the visible light wavelength of human beings is 380 to 780 nm and the visual sensitivity is a bell shape having a peak in the vicinity of 550 nm, visible light is effective in such a dispersion containing 6 borohydride fine particles. It is understood that it penetrates into the light and effectively reflects and absorbs other heat rays.

In addition, the infrared absorption capacity per unit weight of the 6-boride fine particles is very high, and the effect can be exhibited at a usage amount of 40 to 1/100 or less as compared with ITO and ATO. Therefore, even if the amount of fine particles added to the desired transparent substrate is small, sufficient infrared absorption ability can be ensured, which has the advantage of not impairing the physical properties of the substrate. Of course, it can be added in a large amount if desired, and the content of the 6-boride fine particles on the surface and / or inside of the transparent substrate is 0.001% by weight or more with respect to the solid content of the transparent substrate. It can be selected in the range of 30% by weight. Further, from the viewpoint of considering the weight of the transparent base material after the addition of the 6-boride fine particles and the raw material cost, it is preferably in the range of 0.005% by weight to 15% by weight, more preferably 0.005% by weight to 10% by weight. It is good to select within the range of. If the addition amount is 0.001% by weight or more, a sufficient infrared absorption effect can be obtained even if the base material is thick, and if it is less than 30% by weight, there is no adverse effect on the dispersion preparation. It is more preferable if it is less than 10% by weight.

Further, it is also preferable to contain fine particles of a substance having an ability to emit far infrared rays on the surface and / or inside of the base material together with the 6 boride fine particles. Examples of the fine particles of the far-infrared radiation material include metal oxides such as ZrO ₂ , SiO ₂ , TiO ₂ , Al ₂ O ₃ , MnO ₂ , MgO, Fe ₂ O ₃ , and CuO, and carbides such as ZrC, SiC, and TiC. _Nitridees such as ZrN, Si 3N ₄ , AlN and the like can be mentioned.

6 The borohydride fine particles have a property of absorbing light energy such as sunlight having a wavelength of 0.3 to 2 μm, and in particular, selectively absorb light in the near infrared region near a wavelength of 1 μm and re-radiate it. Or convert to heat. The above-mentioned fine particles of the far-infrared radiation substance have the ability to receive the energy absorbed by the 6-bodied fine particles, convert it into heat energy of medium and far-infrared wavelengths, and radiate it. For example, the ZrO ₂ fine particles convert the heat absorbed by the 6-boride fine particles into heat energy having a wavelength of 2 to 20 μm and radiate it. Therefore, the absorbed energy is exchanged between the fine particles and radiated efficiently, so that more effective heat retention is achieved.

Next, the preferable particle size of the 6-boride fine particles will be described.

As described above, the average particle size of the 6-boride fine particles is required to be 10 nm to 500 nm, and can be appropriately selected from the above range depending on the purpose of use. First, when used for applications that maintain transparency, it is preferable to have a particle size of 500 nm or less. This is because particles smaller than 500 nm do not completely block light due to scattering, and can maintain visibility in the visible light region and at the same time efficiently maintain transparency. In particular, when the transparency in the visible light region is emphasized, it is preferable to further consider scattering by particles.

Further, from the viewpoint of design, it is required to efficiently shield near infrared rays while maintaining transparency. However, when the particle size of the 6 borohydride fine particles is large, the light in the visible light region of 400 to 780 nm is scattered by geometrical scattering or diffraction scattering to become like frosted glass, and it becomes difficult to obtain clear transparency. Therefore, when the particle size of the 6-boride fine particles is smaller than 500 nm, visible light is not shielded, so that near-infrared rays can be efficiently shielded while maintaining the transparency of the visible light region.

Further, when the diameter of the 6-boride fine particles is 200 nm or less, the scattering is reduced to become a Mie scattering or Rayleigh scattering region. In particular, when the particle size is reduced to the Rayleigh scattering region, the scattered light intensity is proportional to the sixth power of the dispersed particle size, so that the scattering is reduced and the transparency is improved as the particle size is reduced. Further, when it is 100 nm or less, the scattered light becomes very small, which is preferable. Therefore, when the transparency in the visible light region is particularly important, the diameter of the 6-boride fine particles is preferably 200 nm or less, more preferably 100 nm or less.

2. 2. Coating film (membrane type) obtained by atomic layer deposition method and its membrane material (reaction gas)
Reaction gases that form a coating film (coating layer) by the ALD method are sold by various companies. Table 1 below shows typical reaction gases of the coating film used in the present invention.

These typical membrane materials (reaction gas) are summarized in Table 1, but are not limited to the membrane materials (reaction gas) shown here. Further, in addition to an oxide film made of these film materials, a similar carbonized film, a nitrided film, or a synthetic film thereof may be used.

3. 3. Coating layer structure
The structure of the coating layer (coating film) formed on the surface of the near-infrared shielding fine particles (composite tungsten oxide fine particles and / or borohydride fine particles) includes a first reaction gas adsorption step, an exhaust step, and a second reaction gas reaction step. Atomic layer deposition (ALD) device using the atomic layer deposition (ALD) method, in which one atomic layer is formed in one cycle consisting of the above-mentioned and exhaust steps, four or more layers of the one atomic layer are formed and one or more kinds are formed. It is sufficient that at least one kind of coating layer (coating film) composed of atomic layers is formed, and the total number of coating films, the order of the films, the combination, the film thickness, and the like are not limited.

For example, an atomic layer deposition (ALD) apparatus using an atomic layer deposition (ALD) method in which one atomic layer is formed in one cycle consisting of a first reaction gas adsorption step and an exhaust step and a second reaction gas reaction step and an exhaust step. As a result, the surface of the near-infrared shielding fine particles (composite tungsten oxide fine particles and / or horide fine particles) 30 shown in FIG. 2 is selected from Al ₂ O _3, SiO ₂ , SiO Al, SiC, SiOC, and SiC N. Examples thereof include a structure in which four or more atomic layers are formed and covered with a coating layer 31.

Further, by the atomic layer deposition (ALD) apparatus using the atomic layer deposition (ALD) method, the surface of the near-infrared shielding fine particles (composite tungsten oxide fine particles and / or borohydride fine particles) 40 shown in FIG. 3 is subjected to Al ₂ The surface of the first coating layer 41 is covered with a first coating layer 41 in which four or more atomic layers selected from O _3, SiO _2, SiOAl, SiC, SiOC, and SiCN are formed. Examples thereof include a structure in which one kind of atomic layer selected from Al ₂ O _{3 and} SiO ₂ is coated with a second coating layer 42 formed by forming one or more layers. The coating layer consisting of one type selected from Al ₂ O _{3 and} SiO ₂ has low oxygen permeability and water vapor permeability, and is effective as a coating layer if one or more atomic layers of one type are formed. Appears.

Further, by the atomic layer deposition (ALD) apparatus using the atomic layer deposition (ALD) method, the surface of the near-infrared shielding fine particles (composite tungsten oxide fine particles and / or borohydride fine particles) 50 shown in FIG. 4 is subjected to Al ₂ From two types of atomic layers 51a and 51b selected from O _3, SiO _2, SiOAl, SiC, SiOC, and SiCN (the total number of atomic layers 51a and 51b is 4 or more). The first coating layer 51 is coated, and the surface of the first coating layer is coated with a second coating layer 52 composed of one atomic layer (one or more layers) selected from Al ₂ O _{3 and} SiO ₂ . The structure can be mentioned.

4. Atomic layer deposition equipment
(1) Atomic Layer Deposition (ALD) Method Atomic Layer Deposition (ALD, sometimes abbreviated as ALD as described above) contains elements that make up the atomic layer (molecular layer). The raw material gas is alternately introduced into the vacuum device, and a single atom (single molecule) is generated by the reaction between the molecules adsorbed on the outermost surface of the film to be deposited placed in the vacuum device and the raw material gas to be introduced next. ) This is a method in which the film thickness of the coating film can be controlled at the atomic layer level by depositing layers at a time (see Non-Patent Document 2).

Since the ALD method is a method in which film formation starts while depositing single atom (single molecule) layers from the film surface to be filmed, a metal film having no pinholes with respect to the film to be filmed (for example, a heat resistant resin film). Can be formed. Further, in the ALD method, since the raw material is gas, the splash phenomenon (a phenomenon in which the film raw material is agglomerated and flies to the film-deposited body) that frequently occurs in the sputtering method or the vacuum vapor deposition method does not occur. Therefore, there is no phenomenon that the splash adheres to the film being formed and falls off to form a pinhole. On the other hand, in the vacuum film formation method (vacuum vapor deposition method, sputtering method, ion plating method, ion beam sputtering method, etc.), metal clusters fly onto the film-deposited object and adhere to the surface of the film-deposited object to form a metal. Since the clusters combine to form a film, there is a possibility of potentially forming pinholes between the metal clusters, which is very different from the ALD method.

In addition, the ALD method enables uniform film formation even on the surface of the film to be filmed, which has irregularities on the surface, which is difficult to form uniformly with the sputtering method and vacuum vapor deposition method, which have high straightness, and has a high aspect ratio. Uniform film formation is possible even with the shape configuration of. Further, the vacuum apparatus used in the ALD method does not require an expensive power supply unit or the like required for the vacuum apparatus used in the PVD method or the CVD method, so that the film formation cost is higher than that of the conventional film formation method. Can also be reduced. Further, it has been found that in the ALD method, a dense film can be obtained even at a low temperature as compared with the film obtained by a general parallel plate type plasma CVD method or the like.

Focusing on these characteristics, the ALD method has been researched and developed as a method for forming a zinc sulfide thin film of an organic EL and a gallium arsenic thin film which is a compound semiconductor. Recently, HfO ₂ / formed by the ALD method has been carried out. An Al ₂ O ₃ film has been proposed as a DRAM capacitor film (see Patent Document 6).

In this ALD method, a first reaction gas (raw material gas) and a second reaction gas (raw material gas) containing each of the elements constituting the atomic layer (molecular layer) are alternately placed in a vacuum apparatus (reaction chamber). One cycle is configured by the following steps A to H to be introduced into the above, and the film thickness is adjusted according to the number of cycles.

A: The process of introducing the first reaction gas (raw material gas) into the vacuum device (reaction chamber),
B: A process in which the first reaction gas is chemically adsorbed on the outermost surface of the film to be deposited.
C: A step in which the outermost surface of the film-deposited body is saturated with the first reaction gas,
D: Step of exhausting excess first reaction gas and by-products from the vacuum device (reaction chamber),
E: The process of introducing the second reaction gas (raw material gas) into the vacuum device (reaction chamber),
F: A step in which the first reaction gas adsorbed on the outermost surface of the film to be formed reacts with the second reaction gas.
G: A step in which the outermost surface of the film-deposited body is saturated with the second reaction gas,
H: A process of exhausting excess second reaction gas and by-products from the vacuum apparatus (reaction chamber).

In the ALD method, by selecting the first reaction gas and the second reaction gas, oxide films such as SiO ₂ , Al ₂ O ₅ , ZrO ₂ , HfO ₂ , Ta ₂ O ₅ , and TiO ₂ , AlN, Nitride film such as TaN, TiN, TaSiN, TiSiN, metal film such as Cu, Ru, Ir, Ni, Pt, fluoride film such as CaF ₂ , SrF ₂ , MgF ₂ , compound film such as GaAs, InP, GaP. Can be formed.

For example, in the case of forming a monatomic (monomolecular) layer of Al ₂ O ₃ in which the most film formation is performed by the ALD method, one cycle is completed in the following four steps.

（ｉｖ）過剰なＴＭＡガスと副生成物ＣＨ₄ガスをパージ排気する。 (I) Water molecules, which are the first reaction gas, are introduced to adsorb OH groups on the outermost surface of the film-deposited body.
(First reaction)
H ₂ O → Surface of film to be filmed: OH + (1/2) H ₂
(Reaction after the first layer)
: O-Al (CH ₃ ) ₂ + 2H ₂ O →: O-Al (OH) ₂ + 2CH ₄
(Ii) Excess water molecules and by-product CH ₄ are purged and exhausted.
(Iii) A second reaction gas TMA [Trimethyl Aluminum: Al (CH ₃ ) ₃ ] gas, which is a raw material gas for the Al ₂ O ₃ membrane, is introduced. TMA molecules react with OH groups to generate CH ₄ gas.
(Reaction of the first layer)
: O-H + Al (CH ₃ ) ₃ →: O-Al (CH ₃ ) ₂ + CH ₄

(Iv) Excessive TMA gas and by-product CH ₄ gas are purged and exhausted.

Since an Al ₂ O ₃ film having a thickness of about 0.1 nm is formed in these four steps, the cycle of the above four steps is repeated until the required film thickness is reached to increase the film thickness.

In addition, when the step (i) of the second cycle is entered through the step (iv) after the (reaction of the first layer) in the step (iii), the reaction is (reaction of the first layer and subsequent layers). Further, in the above-mentioned steps A to H, the steps A to C correspond to the above step (i), the step D corresponds to the above step (ii), and the steps E to G correspond to the above step (iii). However, the H step corresponds to the above (iv) step.

Further, in order to promote the reaction, the ALD method is a method in which the film-deposited body is heated (100 to 300 ° C.) or plasma is directly applied at the time of the reaction between the first reaction gas and the second reaction gas. , A plasma ALD method such as a method of introducing a reactive group activated by using plasma outside the reaction chamber into the reaction chamber can be performed.

In the ALD method, the reaction gas is different even in the membrane types other than the exemplified Al ₂ O ₃ layer, and basically, "introduction of the first reaction gas", "purge", and "introduction of the second reaction gas" are performed. , And "purge", one layer can be formed. Further, since impurities are rarely incorporated in the film formation by the ALD method and there is a purification action, a high-purity film can be obtained even if a reaction gas having a low purity is used.

(2) Atomic layer deposition (ALD) device used in the method of the present invention Regarding the atomic layer deposition (ALD) device used in the method of the present invention, the first reaction gas adsorption step and the exhaust step and the second reaction gas reaction step and the exhaust An atomic layer deposition (ALD) device capable of semi-continuously performing a "one-cycle process" consisting of steps will be described as an example.

As shown in FIG. 5, this atomic layer depositing device has a first vacuum chamber 331 into which a certain amount of near-infrared shielding fine particles are introduced, and a fine particle 336 introduced from the first vacuum chamber 331 via an opening / closing valve 312 for moving fine particles. A second vacuum chamber 332 that chemically adsorbs the first reaction gas and a fine particle 337 that chemically adsorbs the first reaction gas from the second vacuum chamber 332 via an opening / closing valve 313 for moving fine particles are introduced into the surface of the second vacuum chamber. It is chemically adsorbed on the surface of the third vacuum chamber 333 that exhausts the excess first reaction gas and by-products flowing from the 332, and the fine particles 337 introduced from the third vacuum chamber 333 via the opening / closing valve 314 for moving the fine particles. A fourth vacuum chamber 334 that forms an atomic layer by reacting the first reaction gas with the second reaction gas, and a fine particle 338 that forms an atomic layer are introduced from the fourth vacuum chamber 334 via an opening / closing valve 315 for moving fine particles. It is composed of an excess second reaction gas flowing from the fourth vacuum chamber 334 and a fifth vacuum chamber 335 for exhausting by-products.
The uppermost first vacuum chamber 331 is provided with a fine particle introduction opening / closing valve 311 for introducing a certain amount of near-infrared shielding fine particles, and the lowermost fifth vacuum chamber 335 is provided with fine particles 338 having an atomic layer formed therein. An on-off valve 316 for discharging particles is provided.
The exhaust mechanism of each vacuum chamber is common to the common exhaust pipe 303 connected to the vacuum pump 301 via the exhaust main valve 302 and the exhaust valves 304, 305, 306, 307, 308 attached to each vacuum chamber. It is composed of individual exhaust pipes connected to the exhaust pipe 303, and suction prevention filters 324, 325, 326, 327, 328 for preventing the suction of fine particles are provided on the vacuum chamber side of the individual exhaust pipes, respectively.
The reaction gas introduction mechanism provided in the second vacuum chamber 332 that performs the first reaction gas adsorption step and the fourth vacuum chamber 334 that performs the second reaction gas reaction step serves as a reaction gas supply source (not shown). It is composed of a reaction gas introduction pipe connected and attached with a gas flow meter (MFC: mass flow controller) 317 and 318, and gas introduction valves 309 and 310 attached to each reaction gas introduction pipe.

The control of opening and closing of each valve related to the introduction, movement, and discharge of fine particles, the control of the exhaust mechanism of the vacuum chamber, and the control of the reaction gas introduction mechanism of the vacuum chamber were added to the atomic layer deposition apparatus. It is done by general control means (not shown).

Hereinafter, the atomic layer deposition apparatus will be specifically described.

The functions of the five vacuum chambers (first vacuum chamber 331, second vacuum chamber 332, third vacuum chamber 333, fourth vacuum chamber 334, and fifth vacuum chamber 335) are described below, but the first vacuum is described below. Chambers 331 to 5th vacuum chamber 335 correspond to four steps of one cycle in which one atomic layer (molecular layer) is formed by the ALD method.

1st vacuum chamber 331: Exhaust chamber 2nd vacuum chamber 332: Chemical adsorption chamber to which the 1st reaction gas for forming a film on the outermost surface of fine particles is supplied 3rd vacuum chamber 333: Excessive 1st reaction gas and by-production Exhaust chamber for exhausting objects 4th vacuum chamber 334: Chemical reaction chamber to which a 2nd reaction gas for forming a film on the outermost surface of fine particles is supplied 5th vacuum chamber 335: Excessive 2nd reaction gas and by-products Exhaust chamber to exhaust

In this atomic layer deposition apparatus, the first vacuum chamber 331 (exhaust chamber), the second vacuum chamber 332 (chemical adsorption chamber), the third vacuum chamber 333 (exhaust chamber), the fourth vacuum chamber 334 (chemical reaction chamber), and , The fifth vacuum chamber 335 (exhaust chamber) is provided with exhaust valves 304, 305, 306, 307, 308, respectively, as described above, and is connected to the common exhaust pipe 303 via each exhaust valve. There is.

A vacuum pump (dry pump) 301 is connected to the common exhaust pipe 303 via an exhaust main valve 302, and the above-mentioned suction prevention filter 324 is used so as not to suck fine particles into the individual exhaust pipes of each vacuum chamber. 325, 326, 327, 328 are attached.

Further, in this atomic layer deposition apparatus, the flow rates of the first reaction gas and the second reaction gas are controlled by a gas flow meter (MFC: mass flow controller) 317 and 318, and each vacuum chamber which is a chemical adsorption chamber and a chemical reaction chamber is controlled. The first reaction gas and the second reaction gas are introduced into each vacuum chamber from the blowing pipes provided in (the second vacuum chamber 332 and the fourth vacuum chamber 334). Reference numerals 329 and 330 indicate filters provided at the tip of the blow pipe.

Further, in this atomic layer deposition apparatus, heating linear members 319, 320, 321, 322, and 323 are wound around the outer peripheral surface of each vacuum chamber in order to promote the reaction.

Further, in this atomic layer depositing device, when the upstream side in the uppermost vacuum chamber 331 and the downstream side in the lowermost vacuum chamber 335 are connected to a vacuum chamber (not shown), a vacuum is ensured. It is also possible to omit the vacuum chamber 331 (exhaust chamber) and the vacuum chamber 335 (exhaust chamber) as conditions so that the vacuum chamber also functions.

Further, in this atomic layer depositing device, one cycle of forming one atomic layer (molecular layer) constituting the coating layer covering the surface of fine particles is half in the first vacuum chamber 331 to the fifth vacuum chamber 335. A powder composed of fine particles which are continuously formed and have one atomic layer (molecular layer) formed can be discharged by opening and closing the fine particle discharge opening / closing valve 316 provided in the lowermost vacuum chamber 335.

In addition, one cycle step of forming one atomic layer (molecular layer) is repeated for the surface-coated near-infrared shielding fine particles in which one atomic layer (molecular layer) is formed by carrying out one cycle step. The number of cycles for forming the atomic layer (molecular layer) can be increased, and four or more atomic layers can be formed to form a coating layer, and the film thickness of the coating layer can be increased.

In order to add a one-cycle step, a vacuum chamber for transfer (not shown) via a fine particle discharge opening / closing valve 316 for discharging fine particles having an atomic layer (molecular layer) formed in the lowermost fifth vacuum chamber 335 (not shown). ) Is provided in communication with each other, and the transfer vacuum chamber is provided in communication with the first vacuum chamber 331 at the uppermost portion via the opening / closing valve 311 for introducing fine particles, and is provided in the transfer vacuum chamber. This is possible by transporting the powder composed of the fine particles on which the atomic layer (molecular layer) is formed by an external transport mechanism and introducing it into the first vacuum chamber 331.

(2) Method for manufacturing surface-coated near-infrared shielding fine particles using the above atomic layer deposition device (a) When near-infrared shielding fine particles are arranged in only one vacuum chamber First, one of the five vacuum chambers The case where the fine particles are arranged only in the vacuum chamber will be described with reference to the movement of the fine particles.

(A-1) The opening / closing valve 311 for introducing fine particles, the opening / closing valve 312, 313, 313, 314, 315 for moving fine particles, and the opening / closing valve 316 for discharging fine particles shown in FIG. 5A are all closed.

(A-2) After starting the vacuum pump (dry pump) 301, the exhaust main valve 302 is opened, and the exhaust valve 304 of the first vacuum chamber 331 (exhaust chamber) and the second vacuum chamber 332 (chemical adsorption chamber) are opened. ), The exhaust valve 306 of the third vacuum chamber 333 (exhaust chamber), the exhaust valve 307 of the fourth vacuum chamber 334 (chemical reaction chamber), and the exhaust valve 308 of the fifth vacuum chamber 335 (exhaust chamber). Open and exhaust.

(A-3) After closing the exhaust valves 304 to 308 of the first to fifth vacuum chambers, only the opening / closing valve 311 for introducing fine particles in the first vacuum chamber 331 (exhaust chamber) is opened, and the first vacuum chamber 331 is opened. A certain amount of fine particles 336 are dropped and introduced into the (exhaust chamber), and then the opening / closing valve 311 for introducing fine particles is closed. Next, the exhaust valves 304 to 308 of the first to fifth vacuum chambers are opened and exhausted.

(A-4) After exhausting, the exhaust valves 304 to 308 of the first to fifth vacuum chambers are closed, and then the opening / closing valve 312 for moving fine particles between the first vacuum chamber 331 and the second vacuum chamber 332 is closed. Is opened, and the fine particles 336 are dropped and introduced into the second vacuum chamber 332 (chemical adsorption chamber), and then the opening / closing valve 312 for moving the fine particles is closed. Next, the exhaust valves 304 to 308 of the first to fifth vacuum chambers are opened and exhausted.

(A-5) With the exhaust valves 304 to 308 of the first to fifth vacuum chambers opened, the gas introduction valve 309 of the second vacuum chamber 332 (chemical adsorption chamber) is opened, and the gas flow meter ( After setting the gas flow rate by MFC) 317, the first reaction gas is introduced into the second vacuum chamber 332 (chemical adsorption chamber) for the set introduction time from the blowing pipe provided at the tip of the filter 329, and then The gas introduction valve 309 is closed.

(A-6) After closing the exhaust valves 304 to 308 of the first to fifth vacuum chambers, the opening / closing valve 313 for moving fine particles between the second vacuum chamber 332 and the third vacuum chamber 333 is opened, and the first reaction is performed. After the fine particles 337 in which the gas is chemically adsorbed on the surface are dropped and introduced into the third vacuum chamber 333 (exhaust chamber) and the opening / closing valve 313 for moving the fine particles is closed, the exhaust of the first to fifth vacuum chambers is performed. The valves 304 to 308 are opened and exhausted, and the excess first reaction gas and by-products that have flowed from the second vacuum chamber 332 into the third vacuum chamber 333 from the exhaust valve 306 are also exhausted.

(A-7) After closing the exhaust valves 304 to 308 of the first to fifth vacuum chambers, the opening / closing valve 314 for moving fine particles between the third vacuum chamber 333 and the fourth vacuum chamber 334 is opened, and the first reaction is performed. The fine particles 337 on which the gas is chemically adsorbed on the surface are dropped and introduced into the fourth vacuum chamber 334 (chemical reaction chamber), and then the opening / closing valve 314 for moving the fine particles is closed. Next, the exhaust valves 304 to 308 of the first to fifth vacuum chambers are opened and exhausted.

(A-8) With the exhaust valves 304 to 308 of the first to fifth vacuum chambers opened, the gas introduction valve 310 of the fourth vacuum chamber 334 (chemical reaction chamber) is opened, and the gas flow meter ( After setting the gas flow rate by MFC) 318, the second reaction gas is introduced into the fourth vacuum chamber 334 (chemical reaction chamber) for the set introduction time from the blowing pipe provided at the tip of the filter 330, and then. The gas introduction valve 310 is closed.

(A-9) After closing the exhaust valves 304 to 308 of the first to fifth vacuum chambers, opening and closing for moving fine particles between the fourth vacuum chamber 334 (chemical reaction chamber) and the fifth vacuum chamber 335 (exhaust chamber). The valve 315 was opened, and the fine particles 338 having the atomic layer (molecular layer) formed by the reaction between the first reaction gas and the second reaction gas were dropped and introduced into the fifth vacuum chamber 335 (exhaust chamber). After closing the opening / closing valve 315 for moving fine particles, the exhaust valves 304 to 308 of the first to fifth vacuum chambers are opened to exhaust the gas, and the exhaust valve 308 further opens the fourth vacuum chamber 334 to the fifth vacuum. Excess second reaction gas and by-products that have flowed into the chamber 335 are also exhausted.

(A-10) After closing the exhaust valves 304 to 308 of the first to fifth vacuum chambers, the opening / closing valve 316 for discharging fine particles in the fifth vacuum chamber 335 (exhaust chamber) is opened, and the fine particles 338 are dropped and discharged. After that, the opening / closing valve 316 for discharging fine particles is closed.

By the above operations (a-1) to (a-10), it is possible to produce near-infrared shielding fine particles in which one atomic layer (molecular layer) is formed on the surface of the fine particles.

In order to add a one-cycle process, between the opening / closing valve 316 for discharging fine particles in the lowermost fifth vacuum chamber 335 (exhaust chamber) and the opening / closing valve 311 for introducing fine particles in the uppermost first vacuum chamber 331 (exhaust chamber). When the transfer vacuum chamber (not shown) having a transfer mechanism inside is provided in communication with the above, the following operation (a-11) is added.

(A-11) The first vacuum chamber located at the uppermost part by the transport mechanism in the transport vacuum chamber for the fine particles 338 that have been dropped and introduced into the transport vacuum chamber (not shown) through the fine particle discharge open / close valve 316. The above operations (a-1) to (a-10) for transporting to the front part of the on-off valve 311 for introducing fine particles in 331 (exhaust chamber) and adding a one-cycle process are repeated.

(B) Case where near-infrared shielding fine particles are arranged in all vacuum chambers Next, a case where the fine particles are arranged in all five vacuum chambers will be described with reference to the movement of the fine particles.

When the fine particles are arranged in all five vacuum chambers, untreated fine particles or fine particles having an atomic layer formed are introduced into the first vacuum chamber 331 (exhaust chamber), and the fine particles are the first. 2 Unlike the case where the near-infrared shielding fine particles are arranged in only one vacuum chamber after being dropped and introduced into the vacuum chamber 332, the fine particles are discharged and the first vacuum chamber 331 (exhaust chamber) in an empty state is discharged. ), The untreated fine particles or the fine particles on which the atomic layer is formed are dropped and introduced again. Then, after the chemical adsorption of the first reaction gas is completed in the second vacuum chamber 332 with respect to the first introduced fine particles, the fine particles in which the first reaction gas is chemically adsorbed on the surface are dropped into the third vacuum chamber 333. At the same time as the introduction, the second fine particles introduced into the first vacuum chamber 331 (exhaust chamber) are dropped and introduced into the second vacuum chamber 332, and the second introduced fine particles are discharged to be the first empty state. The third fine particle is dropped and introduced into the vacuum chamber 331 (exhaust chamber) again. This means that the near-infrared shielding fine particles are arranged in all the vacuum chambers by performing these steps semi-continuously.

(B-1) Through the above steps, each processing operation is performed in each of the first to fifth vacuum chambers, and the first vacuum chamber 331, the second vacuum chamber 332, the third vacuum chamber 333, and the fourth vacuum chamber are performed. A certain amount of fine particles are arranged in the entire vacuum chambers of the 334 and the fifth vacuum chamber 335.

(B-2) After the processing operation in each vacuum chamber is completed, the exhaust valves 304 to 308 of the first to fifth vacuum chambers are closed, and after that, only the opening / closing valve 316 for discharging fine particles of the fifth vacuum chamber 335 is closed. Is opened to discharge the fine particles 338 in which the atomic layer is formed.

(B-3) After closing the opening / closing valve 316 for discharging fine particles, the exhaust valves 304 to 308 of the first to fifth vacuum chambers are opened and exhausted, and then the exhaust of the first to fifth vacuum chambers is exhausted. Close the valves 304-308. Next, only the opening / closing valve 315 for moving fine particles between the 5th vacuum chamber 335 and the 4th vacuum chamber 334 is opened, and the processed fine particles are introduced into the 5th vacuum chamber 335 from the 4th vacuum chamber 334.

(B-4) After closing the opening / closing valve 315 for moving fine particles between the 5th vacuum chamber 335 and the 4th vacuum chamber 334, the exhaust valves 304 to 308 of the 1st to 5th vacuum chambers are opened and exhausted. After that, the exhaust valves 304 to 308 of the first to fifth vacuum chambers are closed. Next, only the opening / closing valve 314 for moving fine particles between the 4th vacuum chamber 334 and the 3rd vacuum chamber 333 is opened, and the processed fine particles 337 are introduced into the 4th vacuum chamber 334 from the 3rd vacuum chamber 333.

(B-5) After closing the opening / closing valve 314 for moving fine particles between the 4th vacuum chamber 334 and the 3rd vacuum chamber 333, the exhaust valves 304 to 308 of the 1st to 5th vacuum chambers are opened and exhausted. After that, the exhaust valves 304 to 308 of the first to fifth vacuum chambers are closed. Next, only the opening / closing valve 313 for moving fine particles between the third vacuum chamber 333 and the second vacuum chamber 332 is opened, and the processed powder is introduced into the third vacuum chamber 333 from the second vacuum chamber 332.

(B-6) After closing the opening / closing valve 313 for moving fine particles between the third vacuum chamber 333 and the second vacuum chamber 332, the exhaust valves 304 to 308 of the first to fifth vacuum chambers are opened and exhausted. After that, the exhaust valves 304 to 308 of the first to fifth vacuum chambers are closed. Next, only the fine particle transfer opening / closing valve 312 between the second vacuum chamber 332 and the first vacuum chamber 331 is opened, and the processed fine particles 336 are introduced into the second vacuum chamber 332 from the first vacuum chamber.

(B-7) After closing the opening / closing valve 312 for moving fine particles between the second vacuum chamber 332 and the first vacuum chamber 331, the exhaust valves 304 to 308 of the first to fifth vacuum chambers are opened and exhausted. After that, the exhaust valves 304 to 308 of the first to fifth vacuum chambers are closed. Next, only the opening / closing valve 311 for introducing fine particles in the first vacuum chamber 331 is opened to introduce untreated fine particles or fine particles having an atomic layer formed in the first vacuum chamber 331, and after the introduction of the fine particles is completed. The opening / closing valve 311 for introducing fine particles is closed.

When the above operation (b-7) is completed, the fine particles are moved and arranged in the vacuum chambers from the upper stage side to the lower stage side in each of the five vacuum chambers, so that the processing operation in each vacuum chamber is performed. Then, after the processing operation in each vacuum chamber is completed, the fine particles are moved and arranged in the vacuum chamber from the upper stage side to the lower stage side by performing the above operations (b-1) to (b-7). Therefore, the processing operation in each vacuum chamber is performed.

By repeating this step, it is possible to semi-continuously produce near-infrared shielding fine particles in which one atomic layer (molecular layer) is formed on the surface of the fine particles.

In this way, even if fine particles are present in all the vacuum chambers (exhaust chamber, chemical adsorption chamber, chemical reaction chamber), the open / close valve 316 for discharging fine particles, the open / close valve 315 for moving fine particles, in order from the vacuum chamber on the downstream side, By operating the 314, 313, 312, and the opening / closing valve 311 for introducing fine particles, the reaction gas is not mixed when the opening / closing valve for moving fine particles is opened.

(C) When fine particles are arranged in separate chambers (every other chamber) of the vacuum chamber Next, regarding the case where fine particles are arranged in every other chamber of the five vacuum chambers via an empty vacuum chamber. The explanation will be given with reference to the movement of fine particles.

When fine particles are arranged in every other chamber, untreated fine particles or fine particles having an atomic layer formed are introduced into the first vacuum chamber 331 (exhaust chamber), and these fine particles are used in the second vacuum chamber. After being dropped and introduced into the 332, unlike the above-mentioned "when the near-infrared shielding fine particles are arranged in all the vacuum chambers", the fine particles are not introduced into the first vacuum chamber 331 (exhaust chamber) and are in an empty state. Leave it as it is. Then, after the chemical adsorption of the first reaction gas to the fine particles introduced into the second vacuum chamber 332 is completed, the fine particles chemically adsorbed on the surface of the first reaction gas are dropped and introduced into the third vacuum chamber 333. In addition, by introducing the second fine particles into the first vacuum chamber 331 (exhaust chamber), the inside of the second vacuum chamber 332 becomes empty. Next, after exhausting the excess first reaction gas and by-products that flowed into the third vacuum chamber 333 from the second vacuum chamber 332, the fine particles chemically adsorbed on the surface of the first reaction gas are collected in the third vacuum chamber 333. The fine particles are dropped and introduced into the fourth vacuum chamber 334, and the second fine particles from the first vacuum chamber 331 are also dropped and introduced into the second vacuum chamber 332, but the fine particles are introduced into the first vacuum chamber 331 (exhaust chamber). Leave empty without installation. By performing these steps semi-continuously, it means that fine particles are arranged in every other chamber.

(C-1) Through the above steps, each processing operation is performed in each of the first to fifth vacuum chambers, and as shown in FIG. 5A, the first vacuum chamber 331, the third vacuum chamber 333 and A certain amount of fine particles are arranged in the fifth vacuum chamber 335.

(C-2) After the processing operation in each vacuum chamber is completed, the exhaust valves 304 to 308 of the first to fifth vacuum chambers are closed. After that, the opening / closing valves 312 and 314 for moving fine particles between the first vacuum chamber 331 and the second vacuum chamber 332 and between the third vacuum chamber 333 and the fourth vacuum chamber 334 were opened, and as shown in FIG. 5 (b). The processed fine particles are introduced into the second vacuum chamber 332 and the fourth vacuum chamber 334 from the upper vacuum chamber, respectively, and the fine particle discharge opening / closing valve 316 of the fifth vacuum chamber 335 is also opened to form an atomic layer. The fine particles 338 are discharged.

(C-3) Open / close valves 312 and 314 for moving fine particles between the first vacuum chamber 331 and the second vacuum chamber 332, between the third vacuum chamber 333 and the fourth vacuum chamber 334, and the open / close valve 316 for discharging fine particles. After closing, the exhaust valves 304 to 308 of the first to fifth vacuum chambers are opened and exhausted in a state where a certain amount of fine particles are present in the second vacuum chamber 332 and the fourth vacuum chamber 334.

(C-4) After the exhaust treatment operation in each of the second vacuum chambers 332 and the fourth vacuum chamber 334 is completed, the exhaust valves 304 to 308 of the first to fifth vacuum chambers are closed. Next, the opening / closing valves 313 and 315 for moving fine particles between the second vacuum chamber 332 and the third vacuum chamber 333 and between the fourth vacuum chamber 334 and the fifth vacuum chamber 335 are opened, and the fine particles processed from the upper vacuum chamber are opened. Is introduced into the third vacuum chamber 333 and the fifth vacuum chamber 335, respectively, and the opening / closing valve 311 for introducing fine particles in the first vacuum chamber 331 is opened to allow untreated fine particles or atomic layers to be contained in the first vacuum chamber 331. After the formed fine particles are introduced and the introduction of the fine particles into the first vacuum chamber 331 is completed, between the second vacuum chamber 332 and the third vacuum chamber 333, and between the fourth vacuum chamber 334 and the fifth vacuum chamber 335, respectively. The opening / closing valve 313, 315 for moving fine particles and the opening / closing valve 311 for introducing fine particles are closed. After that, the exhaust valves 304 to 308 of the first to fifth vacuum chambers are opened and exhausted.

When the operation (c-4) is completed, a certain amount of fine particles are moved and arranged in the first vacuum chamber 331, the third vacuum chamber 333, and the fifth vacuum chamber 335 shown in FIG. 5 (a). Perform processing operations in a vacuum chamber. After the processing operation in each vacuum chamber is completed, the operations (c-1) to (c-4) are performed to move and arrange the fine particles from the upper stage side to the lower stage side vacuum chamber, and the processing operation in each vacuum chamber is performed. .. By repeating this step, it is possible to semi-continuously produce near-infrared shielding fine particles in which one atomic layer (molecular layer) is formed on the surface of the fine particles.

By operating as described in (c-1) to (c-4) above, the opening / closing valve 312 and 314 for moving fine particles and the opening / closing valve 316 for discharging fine particles are simultaneously opened [that is, operated (c-2)]. However, the first reaction gas and the second reaction gas are not mixed, and the opening / closing valve 313/315 for moving fine particles and the opening / closing valve 311 for introducing fine particles are simultaneously opened [that is, operated (c-4)]. However, the first reaction gas and the second reaction gas are not mixed.

Hereinafter, reference examples and examples according to the present invention will be specifically described.

[Reference Example 1]
Applying the atomic layer deposition equipment shown in FIG. 5, composite tungsten oxide fine particles with an average particle size of 50 nm, which are near-infrared shielding fine particles, Cs _0.33 WO ₃ (manufactured by Sumitomo Metal Mining Co., Ltd., hereinafter abbreviated as CWO fine particles). An Al ₂ O ₃ film consisting of a single atomic layer was formed on the surface of (1).

In the atomic layer depositing device, a transport vacuum chamber (not shown) is provided in communication with the lowermost fifth vacuum chamber 335 via the fine particle discharge opening / closing valve 316, and the uppermost vacuum chamber is provided. The transfer vacuum chamber is provided in communication with the first vacuum chamber 331 via an opening / closing valve 311 for introducing fine particles, and an atomic layer is formed by a transfer mechanism (not shown) provided in the transfer vacuum chamber. The fine particles can be conveyed and introduced into the first vacuum chamber 331. Therefore, the number of atomic layer forming cycles can be increased by repeating the one-cycle process for the near-infrared shielding fine particles in which one atomic layer is formed by carrying out the one-cycle process.

Hereinafter, a procedure for manufacturing surface-coated near-infrared shielding fine particles in which an Al ₂ O ₃ film (1 atomic layer) constituting a part of the coating layer is formed on the surface of CWO fine particles will be described.

(1-1) The on-off valve for introducing fine particles 311, the on-off valve for moving fine particles 312, 313, 314, 315, and the on-off valve for discharging fine particles 316 shown in FIG. 5 (a) were all closed.

(1-2) After starting the vacuum pump (dry pump) 301, the exhaust main valve 302 is opened, and the exhaust valve 304 of the first vacuum chamber 331 (exhaust chamber) and the second vacuum chamber 332 (chemical adsorption chamber) are opened. Open the exhaust valve 305, the exhaust valve 306 of the third vacuum chamber 333 (exhaust chamber), the exhaust valve 307 of the fourth vacuum chamber 334 (chemical reaction chamber), and the exhaust valve 308 of the fifth vacuum chamber 335 (exhaust chamber). And exhausted.

(1-3) After closing the exhaust valves 304 to 308 of the first to fifth vacuum chambers, only the opening / closing valve 311 for introducing fine particles in the first vacuum chamber 331 (exhaust chamber) is opened, and the first vacuum chamber 331 (1st vacuum chamber 331 (exhaust chamber) is opened. 5 g of CWO fine particles (composite tungsten oxide fine particles) 336 were dropped and introduced into the exhaust chamber), and then the opening / closing valve 311 for introducing the particles was closed. Next, the exhaust valves 304 to 308 of the first to fifth vacuum chambers were opened and exhausted.

(1-4) After exhausting, the exhaust valves 304 to 308 of the first to fifth vacuum chambers are closed, and then the opening / closing valve 312 for moving fine particles between the first vacuum chamber 331 and the second vacuum chamber 332 is closed. The CWO fine particles 336 were dropped and introduced into the second vacuum chamber 332 (chemical adsorption chamber), and then the opening / closing valve 312 for moving the fine particles was closed. Next, the exhaust valves 304 to 308 of the first to fifth vacuum chambers were opened and exhausted.

(1-5) With the exhaust valves 304 to 308 of the first to fifth vacuum chambers opened, the gas introduction valve 309 of the second vacuum chamber 332 (chemical adsorption chamber) is opened, and the gas flow meter (MFC) is opened. From the blow pipe (having a filter 329 at the tip of the pipe) to the second vacuum chamber 332 (chemical adsorption chamber), the flow rate of the water vapor as the first reaction gas is set to 30 sccm and the introduction time is set to 5 minutes by 317. The first reaction gas (steam) was introduced into the inside for 5 minutes, and then the gas introduction valve 309 was closed.

(1-6) After closing the exhaust valves 304 to 308 of the first to fifth vacuum chambers, the opening / closing valve 313 for moving fine particles between the second vacuum chamber 332 and the third vacuum chamber 333 is opened, and the first reaction is performed. After the CWO fine particles 337 chemically adsorbed on the surface of the gas (steam) are dropped and introduced into the third vacuum chamber 333 (exhaust chamber) and the opening / closing valve 313 for moving the fine particles is closed, the first to fifth vacuum chambers are used. The exhaust valves 304 to 308 were opened and exhausted, and the excess first reaction gas and by-products flowing into the third vacuum chamber 333 from the second vacuum chamber 332 were exhausted from the exhaust valve 306 for 5 minutes. ..

(1-7) After closing the exhaust valves 304 to 308 of the first to fifth vacuum chambers, the opening / closing valve 314 for moving fine particles between the third vacuum chamber 333 and the fourth vacuum chamber 334 is opened, and the first reaction gas is opened. CWO fine particles 337 chemically adsorbed on the surface were dropped and introduced into the fourth vacuum chamber 334 (chemical reaction chamber), and then the opening / closing valve 314 for moving the fine particles was closed. Next, the exhaust valves 304 to 308 of the first to fifth vacuum chambers were opened and exhausted.

(1-8) With the exhaust valves 304 to 308 of the first to fifth vacuum chambers opened, the gas introduction valve 310 of the fourth vacuum chamber 334 (chemical reaction chamber) is opened, and the gas flow meter (MFC) is opened. By 318, the flow rate of TMA (Trimethyl Aluminum), which is the second reaction gas, was set to 30 sccm, and the introduction time was set to 5 minutes. The second reaction gas (TMA) was introduced into the chemical reaction chamber) for 5 minutes, and then the gas introduction valve 310 was closed.

(1-9) After closing the exhaust valves 304 to 308 of the 1st to 5th vacuum chambers, the opening / closing valve for moving fine particles between the 4th vacuum chamber 334 (chemical reaction chamber) and the 5th vacuum chamber 335 (exhaust chamber). CWO fine particles 338 in which one atomic layer is formed by the reaction between the first reaction gas (steam) and the second reaction gas (TMA) by opening 315 are dropped and introduced into the fifth vacuum chamber 335 (exhaust chamber). Then, after closing the opening / closing valve 315 for moving fine particles, the exhaust valves 304 to 308 of the first to fifth vacuum chambers are opened and exhausted, and the exhaust valves 308 are used to exhaust the fourth vacuum chamber 334 to the fifth vacuum. Excess second reaction gas and by-products that flowed into chamber 335 were evacuated for 5 minutes.

(1-10) After closing the exhaust valves 304 to 308 of the first to fifth vacuum chambers, the opening / closing valve 316 for discharging fine particles in the fifth vacuum chamber 335 (exhaust chamber) is opened, and the atomic layer of the above one layer is formed. After the formed CWO fine particles 338 were dropped and discharged, the fine particle discharge opening / closing valve 316 was closed.

The surface-coated near-infrared shielding fine particles according to Reference Example 1 in which one Al ₂ O ₃ film (atomic layer) was formed on the surface of the CWO fine particles by the above operations (1-1) to (1-10) were produced.

[Example 1, reference example 2]
In Reference Example 1 above, after forming one layer of Al ₂ O ₃ film (atomic layer) in one cycle step, the first layer is passed from the lowermost fifth vacuum chamber 335 (exhaust chamber) through the above-mentioned transfer vacuum chamber. Using a transport mechanism that transports CWO fine particles to the upper first vacuum chamber 331 (exhaust chamber), one cycle step of atomic layer formation is repeated, and Al ₂ O ₃ film (atomic layer) is formed multiple times (number of atomic layers). 2 to 16 layers).

That is, in the surface-coated near-infrared shielding fine particles according to Reference Example 2 in which the number of atomic layers constituting the coating layer is two, and in Example 1 in which the number of atomic layers constituting the coating layer is 4, 8, and 16. The surface-coated near-infrared shielding fine particles were produced.

[Reference Example 3]
Applying the above atomic layer deposition equipment shown in FIG. 5, a single atomic layer is applied to the surface of composite tungsten oxide fine particles Cs _0.33 WO ₃ (sometimes abbreviated as CWO fine particles) having an average particle size of 50 nm, which are near-infrared shielding fine particles. A SiO ₂ film composed of was formed.

Hereinafter, a procedure for manufacturing surface-coated near-infrared shielding fine particles in which a SiO ₂ film (1 atomic layer) constituting a part of the coating layer is formed on the surface of CWO fine particles will be described.

(3-1) The on-off valve for introducing fine particles 311, the on-off valve for moving fine particles 312, 313, 314, 315, and the on-off valve for discharging fine particles 316 shown in FIG. 5 (a) were all closed.

(3-2) After starting the vacuum pump (dry pump) 301, the exhaust main valve 302 is opened, and the exhaust valve 304 of the first vacuum chamber 331 (exhaust chamber) and the second vacuum chamber 332 (chemical adsorption chamber) Open the exhaust valve 305, the exhaust valve 306 of the third vacuum chamber 333 (exhaust chamber), the exhaust valve 307 of the fourth vacuum chamber 334 (chemical reaction chamber), and the exhaust valve 308 of the fifth vacuum chamber 335 (exhaust chamber). And exhausted.

(3-3) After closing the exhaust valves 304 to 308 of the first to fifth vacuum chambers, only the opening / closing valve 311 for introducing fine particles of the first vacuum chamber 331 (exhaust chamber) is opened, and the first vacuum chamber 331 ( 5 g of CWO fine particles (composite tungsten oxide fine particles) 336 were dropped and introduced into the exhaust chamber), and then the opening / closing valve 311 for introducing fine particles was closed. Next, the exhaust valves 304 to 308 of the first to fifth vacuum chambers were opened and exhausted.

(3-4) After exhausting, the exhaust valves 304 to 308 of the first to fifth vacuum chambers are closed, and then the opening / closing valve 312 for moving fine particles between the first vacuum chamber 331 and the second vacuum chamber 332 is closed. The CWO fine particles 336 were dropped and introduced into the second vacuum chamber 332 (chemical adsorption chamber), and then the opening / closing valve 312 for moving the fine particles was closed. Next, the exhaust valves 304 to 308 of the first to fifth vacuum chambers were opened and exhausted.

(3-5) With the exhaust valves 304 to 308 of the first to fifth vacuum chambers opened, the gas introduction valve 309 of the second vacuum chamber 332 (chemical adsorption chamber) is opened, and the gas flow meter (MFC) is opened. From the blow pipe (having a filter 329 at the tip of the pipe) to the second vacuum chamber 332 (chemical adsorption chamber), the flow rate of the water vapor as the first reaction gas is set to 30 sccm and the introduction time is set to 5 minutes by 317. The first reaction gas (steam) was introduced into the inside for 5 minutes, and then the gas introduction valve 309 was closed.

(3-6) After closing the exhaust valves 304 to 308 of the first to fifth vacuum chambers, the opening / closing valve 313 for moving fine particles between the second vacuum chamber 332 and the third vacuum chamber 333 is opened, and the first reaction is performed. After the CWO fine particles 337 chemically adsorbed on the surface of the gas (steam) are dropped and introduced into the third vacuum chamber 333 (exhaust chamber) and the opening / closing valve 313 for moving the fine particles is closed, the first to fifth vacuum chambers are used. The exhaust valves 304 to 308 were opened and exhausted, and the excess first reaction gas and by-products flowing into the third vacuum chamber 333 from the second vacuum chamber 332 were exhausted from the exhaust valve 306 for 5 minutes. ..

(3-7) After closing the exhaust valves 304 to 308 of the first to fifth vacuum chambers, the opening / closing valve 314 for moving fine particles between the third vacuum chamber 333 and the fourth vacuum chamber 334 is opened, and the first reaction gas is opened. CWO fine particles 337 chemically adsorbed on the surface were dropped and introduced into the fourth vacuum chamber 334 (chemical reaction chamber), and then the opening / closing valve 314 for moving the fine particles was closed. Next, the exhaust valves 304 to 308 of the first to fifth vacuum chambers were opened and exhausted.

(3-8) With the exhaust valves 304 to 308 of the first to fifth vacuum chambers opened, the gas introduction valve 310 of the fourth vacuum chamber 334 (chemical reaction chamber) is opened, and the gas flow meter (MFC) is opened. The flow rate of TDMS, which is the second reaction gas, was set to 30 sccm by 318, and the introduction time was set to 5 minutes, from the blow pipe (having a filter 330 at the tip of the pipe) to the fourth vacuum chamber 334 (chemical reaction chamber). The second reaction gas (TDMS) was introduced into the inside for 5 minutes, and then the gas introduction valve 310 was closed.

(3-9) After closing the exhaust valves 304 to 308 of the 1st to 5th vacuum chambers, the opening / closing valve for moving fine particles between the 4th vacuum chamber 334 (chemical reaction chamber) and the 5th vacuum chamber 335 (exhaust chamber). CWO fine particles 338 in which one atomic layer is formed by the reaction between the first reaction gas (steam) and the second reaction gas (TDMAS) by opening 315 are dropped and introduced into the fifth vacuum chamber 335 (exhaust chamber). Then, after closing the opening / closing valve 315 for moving fine particles, the exhaust valves 304 to 308 of the first to fifth vacuum chambers are opened and exhausted, and the exhaust valves 308 are used to exhaust the fourth vacuum chamber 334 to the fifth vacuum. Excess second reaction gas and by-products that flowed into chamber 335 were evacuated for 5 minutes.

(3-10) After closing the exhaust valves 304 to 308 of the first to fifth vacuum chambers, the opening / closing valve 316 for discharging fine particles of the fifth vacuum chamber 335 (exhaust chamber) is opened, and the atomic layer of the above one layer is formed. After the formed CWO fine particles 338 were dropped and discharged, the fine particle discharge opening / closing valve 316 was closed.

The near-infrared shielding fine particles according to Reference Example 3 in which one SiO ₂ film (atomic layer) was formed on the surface of the CWO fine particles by the above operations (3-1) to (3-10) were produced.

[Example 2, Reference Example 4]
In Reference Example 3 above, after forming one SiO ₂ film (atomic layer) in one cycle step, the uppermost vacuum chamber 335 (exhaust chamber) at the lowermost part passes through the above-mentioned transport vacuum chamber. One cycle step of atomic layer formation is repeated using a transfer mechanism for transporting CWO fine particles to the first vacuum chamber 331 (exhaust chamber), and the SiO ₂ film (atomic layer) is formed multiple times (the number of atomic layers is 2 to 16). )went.

That is, in the surface-coated near-infrared shielding fine particles according to Reference Example 4 in which the number of atomic layers constituting the coating layer is two, and in Example 2 in which the number of atomic layers constituting the coating layer is 4, 8, and 16. The surface-coated near-infrared shielding fine particles were produced.

[Example 3]
The above atomic layer deposition apparatus shown in FIG. 5 is applied to form one Al ₂ O ₃ film (atomic layer) in one cycle step in the same manner as in Example 1, and then the lowermost fifth vacuum chamber 335. One cycle step of atomic layer formation is repeated from (exhaust chamber) to the uppermost first vacuum chamber 331 (exhaust chamber) via the above-mentioned transport vacuum chamber by using a transport mechanism for transporting CWO fine particles to 4 atoms. A first coated layer composed of an Al ₂ O ₃ film (atomic layer) was formed.

Next, after changing the second reaction gas to be introduced into the fourth vacuum chamber 334 (chemical reaction chamber) from TMA to TDMS, the 4-atomic layer Al ₂ O ₃ film (atomic layer) is the same as in Reference Example 3. ), A second coating layer composed of a 1-atomic layer SiO ₂ film (atomic layer) was formed on the surface of the first coating layer.

That is, a first coating layer composed of composite tungsten oxide fine particles (CWO fine particles) having an average particle size of 50 nm, an Al ₂ O ₃ film (atomic layer) having a 4-atomic layer covering the surface of the fine particles, and the first coating layer. The surface-coated near-infrared shielding fine particles according to Example 3 composed of a second coating layer composed of a SiO ₂ film (atomic layer) having one atomic layer covering the surface were produced.

[Environment resistance, moisture resistance test]
8 parts by weight, 84 parts by weight of toluene, and 8 parts by weight of the dispersant were mixed with the surface-coated near-infrared shielding fine particles obtained in Reference Examples 1 to 4 and Examples 1 to 3, and the dispersion treatment was performed by a bead mill to prepare a dispersion liquid. Made.

10 parts by weight of the obtained dispersion liquid and 5 parts by weight of an ultraviolet curable resin for hard coating (solid content 100%) are mixed to prepare a coating liquid for forming a shielding film, which is applied onto a quartz glass substrate using a bar coater. To form a film.

The formed film was dried at 60 ° C. for 30 seconds, the solvent was evaporated, and then the film was cured with the light of a high-pressure mercury lamp to obtain a near-infrared shielding film.

The following "ultraviolet irradiation test" was carried out on the obtained near-infrared shielding film, and the change in the maximum transmittance in the visible wavelength region (around 500 nm) was measured by a spectrophotometer.

In addition, the following "high temperature and high humidity environment test" was carried out, and the change in transmittance in the infrared wavelength region (around 820 nm) was measured with a spectrophotometer.

<1> Ultraviolet irradiation test An "ultraviolet irradiation test" was performed using an eye UV tester (manufactured by Iwasaki Electric).

As the exposure conditions, the metal halide lamp intensity was 100 mW / cm ² , the exposure time was 1 hour, and the exposure surface was from the film surface of the sample.

<2> High temperature and high humidity environment test The obtained near-infrared shielding film test sample was exposed to 85 ° C. and 95% RH environment for 3 days, and the change in the maximum infrared transmittance before and after the high temperature and high humidity environment test was measured. did.

<3> The obtained test results are shown in Tables 2 and 3.

As a comparative example, Table 2 shows the results of a test sample obtained by using a composite tungsten oxide powder having no coating layer formed (that is, the number of atomic layers is 0).

[evaluation]
(1) When a coating layer is formed on the surface of composite tungsten oxide fine particles (CWO fine particles) by the ALD method, the effect appears when the number of atomic layers constituting the coating layer is two or more, but the ultraviolet irradiation test and high temperature and high humidity environment It is confirmed that a slight deterioration is observed in the test (see Reference Example 2 and Reference Example 4).

(2) However, when the number of atomic layers constituting the coating layer is one, it is also confirmed that there is no difference from the comparative example (the number of atomic layers is 0) (see Reference Example 1 and Reference Example 3).

(3) On the other hand, when the number of atomic layers constituting the coating layer is 4 or more (Examples 1 and 2), and the number of atomic layers constituting the first coating layer is 4 and the second coating layer is formed. In the case of one layer (Example 3), it is confirmed that the infrared shielding performance of the composite tungsten oxide fine particles (CWO fine particles) is not deteriorated by the irradiation with ultraviolet rays or the high temperature and high humidity environment.

The surface-coated near-infrared shielding fine particles obtained by the method of the present invention can suppress decomposition deterioration and characteristic deterioration phenomenon caused by water vapor, ultraviolet irradiation, etc., and are therefore added to coating films, various resin kneaded substrates, laminated glass, and the like. It has industrial applicability to be used as a solar shielding material.

1 WO ₆ units 2 elements M
30 Near-infrared shielding fine particles 31 Coating layer 40 Near-infrared shielding fine particles 41 First coating layer 42 Second coating layer 50 Near-infrared shielding fine particles 51 First coating layer 51a Atomic layer 51b Atomic layer (atomic layer different from 51a)
52 Second coating layer 301 Vacuum pump 302 Exhaust main valve 303 Common exhaust pipe 304, 305, 306, 307, 308 Exhaust valve
309, 310 Gas introduction valve 311 Open / close valve for introducing fine particles 312, 313, 314, 315 Opening / closing valve for moving fine particles 316 Open / close valve for discharging fine particles 317, 318 Gas flow meter (MFC: Mass flow controller)
319, 320, 321, 322, 323 Heating linear member 324, 325, 326, 327, 328 Suction prevention filter 329, 330 Filter 331 First vacuum chamber (exhaust chamber)
332 Second vacuum chamber (chemical adsorption chamber)
333 Third vacuum chamber (exhaust chamber)
334 4th vacuum chamber (chemical reaction chamber)
335 5th vacuum chamber (exhaust chamber)
336, 337, 338 fine particles

Claims (7)

In a method for producing surface-coated near-infrared shielding fine particles, which comprises a near-infrared shielding fine particle and a coating layer covering the surface of the near-infrared shielding fine particle.
One or more types of near-infrared shielding fine particles having an average particle size of 10 to 500 nm selected from composite tungsten oxide fine particles and borohydride fine particles, and Al ₂ O _3, SiO ₂ , SiO Al, SiC, SiOC, and SiC N are selected and close to each other. The surface-coated near-infrared shielding fine particles are composed of a coating layer composed of one or more atomic layers that coat the surface of the infrared-shielding fine particles.
The atomic layer deposition (ALD) apparatus using an atomic layer deposition (ALD) method in which one atomic layer is formed in one cycle consisting of a first reaction gas adsorption step and an exhaust step and a second reaction gas reaction step and an exhaust step. A method for producing surface-coated near-infrared shielding fine particles, which comprises forming four or more atomic layers to form a coating layer composed of one or more atomic layers. In a method for producing surface-coated near-infrared shielding fine particles composed of a near-infrared shielding fine particle and a coating layer covering the surface of the near-infrared shielding fine particle.
One or more kinds of near-infrared shielding fine particles having an average particle size of 10 to 500 nm selected from composite tungsten oxide fine particles and borohydride fine particles, and Al ₂ O _3, SiO ₂ , SiO Al, SiC, SiOC, and SiC N are selected and close to each other. A first coating layer consisting of one or more atomic layers covering the surface of infrared shielding fine particles, and a second consisting of one or more atomic layers selected from Al ₂ O _{3 and} SiO ₂ and covering the surface of the first coating layer. The coating layer constitutes the surface-coated near-infrared shielding fine particles.
The atomic layer deposition (ALD) apparatus using the atomic layer deposition (ALD) method, in which one atomic layer is formed in one cycle consisting of a first reaction gas adsorption step and an exhaust step and a second reaction gas reaction step and an exhaust step, is used. One atomic layer is formed into four or more layers to form a first coating layer composed of one or more atomic layers, and at the same time.
It is characterized in that one or more atomic layers are formed by an atomic layer deposition (ALD) apparatus using the atomic layer deposition (ALD) method to form a second coating layer composed of one or more atomic layers. A method for producing surface-coated near-infrared shielding fine particles. A plurality of vacuum chambers having an exhaust mechanism are arranged in vertical direction via an opening / closing valve for moving fine particles that controls the movement of near-infrared shielding fine particles, and the first reaction gas adsorption step and the second reaction gas reaction are described above. A claim characterized in that the coating layer or the first coating layer and the second coating layer are formed by using an atomic layer deposition (ALD) device provided with a reaction gas introduction mechanism in at least a pair of vacuum chambers in which the steps are performed. Item 2. The method for producing surface-coated near-infrared shielding fine particles according to Item 1 or 2. The plurality of vacuum chambers chemically apply the first reaction gas to the surface of the first vacuum chamber into which a certain amount of near-infrared shielding fine particles are introduced and the surface of the fine particles introduced from the first vacuum chamber via an opening / closing valve for moving the fine particles. The fine particles that chemically adsorbed the first reaction gas from the second vacuum chamber via the second vacuum chamber to be adsorbed and the opening / closing valve for moving the fine particles were introduced and by-produced with the excess first reaction gas that flowed from the second vacuum chamber. One atom by reacting the first reaction gas and the second reaction gas chemically adsorbed on the surface of the fine particles introduced from the third vacuum chamber through the third vacuum chamber for exhausting the object and the opening / closing valve for moving the fine particles. The fine particles having formed a single atomic layer were introduced from the 4th vacuum chamber via the 4th vacuum chamber forming the layer and the opening / closing valve for moving the fine particles, and the excess second reaction gas and by-production flowing from the 4th vacuum chamber were introduced. It is composed of a fifth vacuum chamber that exhausts things, and the first vacuum chamber at the top is provided with an on-off valve for introducing fine particles that introduces a certain amount of near-infrared shielding fine particles, and the fifth vacuum at the bottom. The atomic layer deposition (ALD) device according to claim 3 is configured by an atomic layer deposition (ALD) device provided with an on-off valve for discharging fine particles for discharging near-infrared shielding fine particles having an atomic layer formed in the chamber. The method for producing surface-coated near-infrared shielding fine particles according to claim 3, wherein the surface-coated near-infrared shielding fine particles are produced. A transport vacuum chamber is provided in communication with the lowermost vacuum chamber provided with a fine particle discharge open / close valve for discharging the near-infrared shielding fine particles on which an atomic layer is formed via the fine particle discharge open / close valve, and the above-mentioned transport is performed. The vacuum chamber is provided in communication with the uppermost vacuum chamber via an opening / closing valve for introducing fine particles, and also transports near-infrared shielding fine particles having an atomic layer formed by a transport mechanism in the transport vacuum chamber. The third or fourth aspect of claim 3 or 4, wherein the atomic layer deposition (ALD) apparatus introduced in the uppermost vacuum chamber constitutes the atomic layer deposition (ALD) apparatus according to claim 4. A method for producing surface-coated near-infrared shielding fine particles. The composite tungsten oxide fine particles are the general formula MxWyOz (M is H, He, alkali metal, alkaline earth metal, rare earth element, Mg, Zr, Cr, Mn, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Tl, Si, Ge, Sn, Pb, Sb, B, F, P, S, Se, Br, Te, Ti, Nb, Represents at least one element selected from the group consisting of V, Mo, Ta, Re, Be, Hf, Os, Bi and I, where x, y, z are 0.01≤x≤1, 0.001. It is composed of composite tungsten oxide fine particles represented by ≦ x / y ≦ 1, 2.2 ≦ z / y ≦ 3.0).
The boride fine particles are composed of the general formula XBm (where X is Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Sr, Ca). At least one kind of metal element selected from the group, m is a numerical value indicating the amount of boron in the above general formula, and is composed of boride fine particles represented by 4.0 ≦ m ≦ 6.2). The method for producing surface-coated near-infrared shielding fine particles according to claim 1 or 2, wherein the surface-coated near-infrared shielding fine particles are produced. In the surface-coated near-infrared shielding fine particles composed of the near-infrared shielding fine particles and the coating layer covering the surface of the near-infrared shielding fine particles.
A surface-coated near-infrared ray-shielding fine particle, which is obtained by the method for producing a surface-coated near-infrared ray-shielding fine particle according to any one of claims 1 to 6.

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