JP2013256104A - Transparent dielectric film, heat-reflecting structure, manufacturing method therefor, and laminated glass using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a means for improving transparency to radio waves while securing excellent thermal insulation and transparency to visible light in a laminate of thin metal films and metal oxide films.SOLUTION: A heat-reflecting structure comprises: a base material; and an alternating laminate which is positioned on the base material, and in which metal layers and dielectric layers are alternately laminated, and the two outermost layers are dielectric layers. The dielectric layer is configured of crystalline regions and amorphous regions of a metal oxide.

Description

  The present invention relates to a transparent dielectric film used for a window material of a vehicle or a building, a heat reflecting structure, a manufacturing method thereof, and a laminated glass using the same. In particular, the present invention relates to a transparent dielectric film, a heat reflecting structure, a manufacturing method thereof, and a laminated glass using the same, which are excellent in visible light transmission and radio wave transmission.

  A high degree of transparency is required for window glass of automobiles, railway vehicles, aircraft, ships, buildings, and the like. In particular, a windshield for automobiles has a visible light transmittance of 70 in order to ensure visibility. % Or more is required. In addition, since these windows have strong demands for penetration resistance and scattering prevention, laminated glass having excellent properties is widely used. Laminated glass generally has an integrated structure by bonding an intermediate layer such as a resin between a pair of glass plates.

  On the other hand, in recent years, for the purpose of reducing the cooling load or suppressing the temperature rise in the room, it has also been proposed to impart a heat ray blocking function to the glass to enhance the heat shielding property of the window glass.

  As a method for imparting a heat ray blocking function, for example, a method of providing a heat ray reflective layer between a pair of glass plates of laminated glass and a method of sticking a heat ray reflective film (heat ray reflective layer) on the surface of the glass plate are known. Yes.

  For example, a method is known in which a metal oxide is dispersed in a resin material constituting an intermediate layer of laminated glass to form a heat ray reflective layer. However, a certain amount of metal oxide is required to disperse the metal oxide in the resin material and exhibit sufficient heat ray blocking properties. In this case, it is difficult to obtain good visible light transmittance. There is. That is, in this method, the heat ray blocking property and the visible light transmittance are in a trade-off relationship, and it is difficult to achieve both of them.

  On the other hand, as a method that can achieve both the heat ray blocking property and the visible light transmission property, a metal thin film (metal layer) having a low electrical resistance such as silver and an amorphous metal oxide film (metal oxide layer) are used. There is a method of using a laminated transparent conductive film as a heat ray reflective layer. Such a transparent conductive film has a metal oxide layer on the surface of the metal layer, so that the surface reflection of the metal layer is canceled out by light interference, and light scattering in the amorphous metal oxide layer is prevented. Therefore, it is excellent in visible light transmittance. Further, the transparent conductive film has high infrared light reflectivity due to the low electrical resistance of the metal layer, and can realize high heat insulation performance. For example, Patent Document 1 discloses a transparent conductive film composed of a metal film made of an alloy containing silver as a main component and an amorphous Zn—Sn—O-based oxide film provided on both surfaces of the metal film. Can be used as a heat ray reflective film and has excellent visible light transmittance.

JP 2007-250430 A

  However, in the transparent conductive film as disclosed in Patent Document 1, the low electrical resistance of the metal film simultaneously provides high radio wave reflection performance. For this reason, there is a problem that radio waves in a wide frequency band such as television, radio, ETC, wireless LAN, and cellular phone are not transmitted, and a communication system using these radio waves cannot be used. Therefore, when using it for the window of a building or a vehicle, the design which provides antennas, such as GPS and ETC outside, will be needed. Thus, with the method of Patent Document 1, it has been difficult to satisfy high visible light transparency and high radio wave transparency.

  Therefore, an object of the present invention is to provide means for improving radio wave permeability while ensuring excellent heat insulation and visible light permeability in a laminate of a metal thin film and a metal oxide film.

  The present inventors have intensively studied to solve the above problems. As a result, the above problem is solved by using a dielectric film composed of a crystalline region and an amorphous region of the metal oxide as the metal oxide film constituting the laminate of the metal thin film and the metal oxide film. As a result, the present invention has been completed.

  That is, according to one aspect of the present invention, a base material, an alternating stack located on the base material, in which metal layers and dielectric layers are alternately stacked, and both outermost layers are dielectric layers. And a heat reflecting structure having a body. The dielectric layer includes a metal oxide crystal region and an amorphous region.

  According to the present invention, it is possible to achieve both high visible light transmittance and high radio wave permeability by configuring the metal oxide film from a metal oxide crystal region and an amorphous region. That is, the presence of the metal oxide crystal region results in a dielectric film having an increased electrical resistivity, and the presence of the metal oxide amorphous region ensures high visible light transmittance. Then, by laminating the dielectric film on the surface of the metal thin film, it is possible to obtain a heat reflecting structure having excellent heat ray reflectivity, visible light transmittance and radio wave transmittance, and a laminated glass using the same. Become.

It is a top view of the laminated glass which is one Embodiment of this invention. It is sectional drawing when the laminated glass 1 of embodiment shown in FIG. 1 is cut | disconnected by plane II-II. It is a schematic cross section which shows the basic composition of the heat reflection film which concerns on one Embodiment of this invention. It is a schematic cross section which shows the basic composition of the heat reflection film which concerns on other one Embodiment of this invention. It is a schematic cross section which shows the dielectric material layer which comprises the heat | fever reflecting film which concerns on other one Embodiment of this invention, (A) is a form in which the crack 23 exists in the surface layer part of the dielectric material layer 17, (B) Indicates a form in which a crack 23 exists inside the dielectric layer 17. It is the photograph which observed the cross section of the ZnSnO film | membrane as a dielectric material layer concerning one Embodiment of this invention with the transmission electron microscope (TEM). It is a schematic diagram of the structure of the ZnSnO film | membrane as a dielectric material layer concerning one Embodiment of this invention. It is the electron beam diffraction image measured with the transmission electron microscope (TEM) of the heat | fever reflection film in Example 1-1. It is an electron beam diffraction image measured with the transmission electron microscope (TEM) of the heat reflection film in the comparative example 4. FIG. It is an electron beam diffraction image measured with the transmission electron microscope (TEM) of the heat | fever reflection film in the comparative example 1. FIG. It is an electron beam diffraction image measured with the transmission electron microscope (TEM) of the heat | fever reflection film in the comparative example 2. FIG. It is an electron beam diffraction image measured with the transmission electron microscope (TEM) of the heat | fever reflection film in the comparative example 3. FIG. It is the electron beam diffraction image measured with the transmission electron microscope (TEM) of the heat | fever reflective film in Example 2-1. It is the photograph which observed the cross section of the mixed film of ZnSnO and ZnAlO as a dielectric material layer used for one Embodiment of this invention with the transmission electron microscope (TEM). It is the photograph which observed the surface of the mixed film of ZnSnO and ZnAlO as a dielectric material layer used for one Embodiment of this invention with the optical microscope. It is a schematic diagram of the structure of the mixed film of ZnSnO and ZnAlO as a dielectric layer which concerns on one Embodiment of this invention. It is a schematic diagram of the structure of the ZnSnO film | membrane as a conventional electroconductive film comprised from the amorphous phase of a metal oxide. It is a schematic cross section which shows the basic composition of the multilayer film which is a transparent base film used for one Embodiment of this invention. It is a schematic cross section showing the basic composition of the heat reflection board concerning one embodiment of the present invention. It is a schematic cross section showing the basic composition of the heat reflection board concerning one embodiment of the present invention. It is a schematic diagram which shows the structure of the opposing target type | mold sputtering device of the roll-to-roll system used for one Embodiment of this invention. FIG. 17 is a schematic perspective view showing a basic configuration of a box-type sputtering unit in the opposed target sputtering apparatus shown in FIG. 16. It is an optical microscope photograph of the surface of the heat-reflective film after extending | stretching manufactured in Example 2-6.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. In addition, this invention is not restrict | limited only to the following embodiment. The dimensional ratios in the drawings are exaggerated for convenience of explanation, and may differ from actual ratios.

  According to one aspect of the present invention, a base material, and an alternating laminate body on which the metal layer and the dielectric layer are alternately laminated, and both outermost layers are dielectric layers, , A heat reflecting structure is provided. The heat reflecting structure according to this embodiment is characterized in that the dielectric layer is composed of a metal oxide crystal region and an amorphous region.

[First Embodiment]
In one embodiment of the present invention, the substrate is a transparent substrate film, and in such a case, the heat reflecting structure functions as a heat reflecting film. That is, in one embodiment of the present invention, the transparent base film and the transparent base film are positioned, the metal layers and the dielectric layers are alternately laminated, and both outermost layers are dielectric layers. It is a heat | fever reflective film which has a certain alternate laminated body. The dielectric layer includes a metal oxide crystal region and an amorphous region.

  The heat reflecting film of the present embodiment can constitute a laminated glass. First, a basic configuration of a laminated glass to which the heat reflecting film of this embodiment can be applied will be described with reference to the drawings.

  FIG. 1 is a plan view of a laminated glass according to an embodiment of the present invention. The laminated glass 1 of the present embodiment is a front window glass of an automobile, is formed according to the shape of the automobile, and has a curved shape according to the shape of the front window. However, the shape of the laminated glass 1 varies depending on the portion to which it is applied, and can have various shapes.

  In general, laminated glass used for window shields of automobiles has many curved surfaces. The laminated glass having such a curved shape is manufactured by sandwiching an intermediate layer and a conductive film between glasses bent in advance to an arbitrary curvature. On the other hand, what is used for a window material for construction may have a flat plate shape that is not bent.

  FIG. 2 shows a cross-sectional view when the laminated glass 1 of the embodiment shown in FIG. 1 is cut along a plane II-II. As shown in FIG. 2, the laminated glass 1 of the present embodiment includes a first glass plate 11, a first intermediate layer 12, a heat reflecting film 13, a second intermediate layer 14, and a second glass. The plate 15 is laminated in this order.

  In the present embodiment, the intermediate layer (12, 14) is interposed between the heat reflecting film 13 and the glass plate (11, 15), but the present invention is not limited to such a form, and the intermediate layer (12, 14) may not be interposed. For example, when the heat reflection film 13 can be in close contact with the glass plate (11, 15), the intermediate layer (12, 14) may not be interposed.

  The use of the laminated glass 1 is not limited to the front window glass of the above-mentioned automobile, but it is used for a side window glass and a rear window glass of an automobile, and for window glasses of railway vehicles other than automobiles, aircraft, ships, buildings, etc. Can also be suitably used.

  Hereinafter, the member which comprises the laminated glass of this embodiment is demonstrated in detail.

(Heat reflection film)
FIG. 3 is a schematic cross-sectional view showing a basic configuration of a heat reflecting film according to an embodiment of the present invention. As shown in FIG. 3, the heat reflecting film 13 includes a transparent base film 16 and an alternating laminate 19 positioned on the transparent base film 16. The alternate laminate 19 is formed by alternately laminating metal layers 18 and dielectric layers 17, and the dielectric layers 17 are disposed on both outermost layers. The present invention is characterized in that the dielectric layer 17 is composed of a metal oxide crystal region and an amorphous region. By configuring the dielectric layer from a crystalline region and an amorphous region of metal oxide, both high visible light transmittance and high radio wave transmittance can be achieved. In other words, the presence of the metal oxide crystal region increases the electrical resistivity, thereby improving radio wave transmission. Furthermore, high visible light transmittance is ensured by the presence of the amorphous region of the metal oxide. And by laminating | stacking this dielectric material film on the surface of a metal thin film, the heat | fever reflective film excellent in heat ray reflectivity, visible light transmittance | permeability, and radio wave transmittance is obtained. Moreover, the laminated glass 1 comprised using this heat | fever reflective film is excellent in heat ray reflectivity, visible light transmittance | permeability, and radio wave transmittance.

  FIG. 4 is a schematic cross-sectional view showing a basic configuration of a heat reflecting film according to another embodiment of the present invention. The heat reflecting film 13 in the form shown in FIG. 4 is different from the heat reflecting film 13 in the form shown in FIG. 3 in that the alternating laminate 19 has cracks 23 in the thickness direction (lamination direction). . In the present invention, the crack is formed in the thickness direction (stacking direction) means that the angle between the line connecting the start point and the end point of the crack and the in-plane direction (horizontal direction) is 45 degrees or more. means. However, in the present invention, the direction of cracks is not limited to the thickness direction (lamination direction), and may be an in-plane direction (horizontal direction).

  Thus, by having a crack in the alternate laminate 19 (dielectric layer 17), radio wave transmission can be further improved. Note that the form shown in FIG. 4 has a crack 23 that penetrates the alternate laminate 19 constituting the heat reflecting film 13 in the thickness direction, that is, the laminate direction of the dielectric layer 17 and the metal layer 18. If the crack 23 exists at least in the dielectric layer 17, an effect of improving radio wave transmission can be obtained. Therefore, the crack 23 does not necessarily have to penetrate through the alternate laminate 19 as shown in FIG. Only a crack may exist. However, it is preferable to have a crack penetrating at least the dielectric layer (dielectric film) 17 in the thickness direction from the viewpoint of further improving the radio wave permeability. As shown in FIG. 4, the dielectric layer 17 and the metal layer It is particularly preferable to have a crack penetrating the alternating laminate 19 composed of 18 in the thickness direction, that is, in the laminate direction of the dielectric layer 17 and the metal layer 18. As for the shape of the crack 23, a form in which the crack penetrates the dielectric layer (dielectric film) 17 in the thickness direction (FIG. 4) and a form in which the crack 23 exists in the surface layer portion of the dielectric layer 17 (FIG. 5). (A)), the form (FIG. 5 (B)) where the crack 23 exists in the inside of the dielectric material layer 17, etc. are mentioned, Furthermore, these combinations may be sufficient. Further, the shape of the crack in the in-plane direction is not particularly limited, and may be any shape such as a dot shape, a line shape, or a mesh shape.

  The width of the crack in the dielectric layer is not particularly limited, but is preferably 400 nm or less. If it is 400 nm or less, the presence of cracks is not confirmed by the naked eye, which is preferable in terms of aesthetics. More preferably, the crack width is 100 nm or less, and more preferably 50 nm or less, from the viewpoint of preventing the dielectric layer (dielectric film) from becoming turbid due to light diffraction due to cracks and lowering the transparency. On the other hand, if there is a crack, radio wave transmission can be improved, so the lower limit of the crack width is not particularly limited and is, for example, 1 nm or more. The crack width refers to the width of the crack in the cross section of the dielectric layer, which is determined by image analysis of an electron micrograph. More specifically, as shown in FIGS. 4 and 5, the distance D in the horizontal direction (in-plane direction of the dielectric layer) of the widest portion of the crack is assumed.

  The depth of the crack is not particularly limited, but as described above, it is preferable that the crack penetrates the dielectric layer 17 and further the alternate laminated body 19 in the thickness direction. Further, the length of the crack in the in-plane direction is not particularly limited, and may be an arbitrary length. The width, depth, length, and shape of the crack can be adjusted according to stretching conditions such as a film stretching process and a pressure-bonding process, which will be described later, and the types and blending ratios of the first metal oxide and the second metal oxide.

In this specification, “having radio wave permeability” means that the electromagnetic wave shielding rate SE measured by the Advantest method is less than 10 dB. Electric wave shielding rate SE is represented by the SN ratio of the received signal X and outgoing signals X ₀ by the following equation. In general, when SE <10 dB, there is no radio wave shielding effect, that is, radio wave permeability. Particularly preferably, SE ≦ 3 dB.

Laminated glass constructed using such a dielectric film or heat reflective film having radio wave transparency can sufficiently ensure radio wave transmissivity, and a radio wave communication system can be used even in a room separated by laminated glass. It can be used.

(Configuration of alternating laminate)
As described above, the alternate stacked body 19 includes the metal layers 18 and the dielectric layers 17. Such an alternating laminate diffracts and reflects infrared light by plasmon resonance of the metal layer, thereby achieving an excellent heat ray blocking function while ensuring visible light transmittance. Infrared light has a large thermal effect, and when absorbed by a substance, it is released as heat, resulting in a temperature rise. From this, it is also called a heat ray, and by blocking these light rays, the temperature rise in the room can be effectively suppressed. Alternating laminates composed of dielectric layers and metal layers are particularly easy to convert into heat, and have excellent reflection characteristics of electromagnetic waves (mid-infrared light) having a wavelength range of 1000 nm or more that cause the temperature of the substance to rise. In addition to having heat insulation performance, it also excels in visible light permeability.

  Generally, a metal totally reflects an electromagnetic wave having a frequency lower than the plasma frequency, that is, an electromagnetic wave on a long wavelength side, reflects a visible ray or a near infrared ray, and has a metallic luster. Therefore, a laminated glass including a normal metal film reflects heat rays. Although the property is high, the visible light transmittance is small. In particular, it is difficult to satisfy the high visible light transmittance required for laminated glass for window shields for automobiles.

  On the other hand, in an alternating laminate in which metal layers are sandwiched between dielectric layers, the energy of the metal band gap changes at the interface between the dielectric film and the metal film. For this reason, plasma vibration generated at the interface between the metal film and the dielectric film is suppressed, and the visible light reflectance is reduced, that is, the visible light transmittance is improved. At this time, the visible light reflection characteristic can be controlled by controlling the number of laminated metal layers and dielectric layers, the thickness, and the refractive index. In addition, radio wave permeability can be controlled by controlling the number and thickness of metal layers. When the metal layer is located on the outermost layer, visible light is reflected and transparency cannot be ensured. Therefore, both outermost layers of the alternating laminate need to be dielectric layers in order to be transparent. Become. Therefore, the number of stacked dielectric layers is the number of stacked metal layers + 1, n metal layers are alternately sandwiched between n + 1 dielectric layers, and the total number of stacked layers is 2n + 1.

  The alternate laminate may have one or more metal layers in order to exhibit a heat ray reflecting function, but two or more metal layers may be used to ensure sufficient heat ray (particularly infrared light) reflectivity. It is preferable to provide. The upper limit of the number of stacked metal layers in the alternately laminated body is not particularly limited, but is preferably 5 layers or less, and more preferably 3 layers or less in order to ensure a visible light transmittance of 70% or more.

  The film thickness of the metal layer and the dielectric film depends on the wavelength range of the light to suppress reflection, the refractive index of the dielectric, and the phase change at the interface between the dielectric film and the metal layer. What is necessary is just to calculate so that it may be canceled by interference.

  The thickness (single layer thickness) of each metal layer is not particularly limited, but is preferably 5 to 30 nm. If the thickness of the metal layer is 5 nm or more, uniform film formation is possible and infrared reflection performance can be exhibited. The plasmon phenomenon is a physical phenomenon in which light is reflected when electrons vibrate in the surface layer of metal, and this dielectric-metal alternate stacking reduces the surface charge density and charge transfer rate and suppresses plasma oscillation. Yes. However, when the thickness of the metal film is increased, plasma vibration is generated in the bulk of the metal, and the visible light transmittance may be significantly reduced. From the viewpoint of preventing the decrease in visible light transmittance due to the inherent visible light absorbability of the metal, the thickness of the metal layer is preferably 30 nm or less. More preferably, in view of excellent heat ray blocking property by effectively reflecting electromagnetic waves (especially infrared rays having a wavelength of 1000 nm or more) that are easily converted into heat while ensuring transparency (high visible light transmittance). ~ 15 nm.

  In addition, since the sum total of the thickness of a metal layer affects visible light transmittance | permeability (transparency), it is preferable that the sum total of the thickness of each layer is 50 nm or less, and it is more preferable that it is 30 nm or less. In this case, if the dielectric film does not absorb visible light, very high transparency can be secured. The lower limit of the total thickness of the metal layer is not particularly limited, but is preferably 3 nm or more from the viewpoint of film forming properties.

  The thickness of each dielectric layer (single layer thickness) is not particularly limited. However, the film thickness of the dielectric layer is preferably 5 nm or more from the viewpoint that uniform film formation is possible and that good visible light transmittance is obtained by preventing metal surface reflection. On the other hand, if the distance between the metal layer surface and the dielectric layer surface becomes too large, antireflection due to light interference in the visible light region cannot be expected, and the visible light transmittance decreases. From this viewpoint, the thickness of the dielectric layer is preferably 100 nm or less. The film thickness of the dielectric layer is more preferably 10 to 75 nm, and further preferably 10 to 50 nm, in order to improve visible light permeability and heat insulation performance.

  More specifically, the thickness of the dielectric film is designed so that light is not reflected in the visible light region (particularly, around 550 nm). What is necessary is just to design by the multilayer film interference of a metal layer.

  In the case of sputtering, the thicknesses of the metal layer and the dielectric film can be controlled by the amount of power during the production and the sputtering time. However, in order to measure a more accurate film thickness, a cross-sectional TEM image is taken and measured from the image.

(Dielectric layer)
The dielectric layer 17 is composed of a metal oxide crystal region and an amorphous region.

  FIG. 6 is a photograph of a cross-section of a ZnSnO film as a dielectric layer used in an embodiment of the present invention, observed with a transmission electron microscope (TEM), and the heat reflecting structure obtained in Example 1-1 described later. It is a TEM photograph of the section of the dielectric material layer in a body. FIG. 7 is a schematic diagram of the structure of a ZnSnO film as a dielectric layer according to an embodiment of the present invention. As shown in FIG. 6, the dielectric layer is composed of an amorphous region 17a and a crystal region 17b of ZnSnO as a metal oxide. More specifically, as shown in FIG. 7, the crystal region 17b is composed of a ZnO crystal phase (crystal grains), and the amorphous region 17a is composed of a ZnSnO amorphous phase.

  Amorphous phase of metal oxide generally has high visible light transmittance and excellent transparency, but has low electrical resistivity and absorbs radio waves by converting them into electric current / vibration. Inferior to On the other hand, the crystalline phase of the metal oxide has high electrical resistivity and excellent radio wave transmission, but has low visible light transmission due to light scattering at the crystal grain boundary. Since the dielectric layer 17 of this embodiment has both the amorphous region 17a of the metal oxide and the crystalline region 17b of the metal oxide, the dielectric layer 17 is excellent from the crystalline phase while ensuring high visible light transparency derived from the amorphous phase. The radio wave transmission can be demonstrated.

  In this specification, the “crystal region” means a crystal structure that can be measured by electron beam diffraction using a transmission electron microscope (TEM), that is, a crystal structure in which a diffraction pattern is confirmed in an electron beam diffraction image of a TEM. Say. Therefore, a structure in which a diffraction pattern is not detected in an electron beam diffraction image of TEM is not included in the “crystal region” in the present invention. That is, when the dielectric layer (dielectric film) is composed only of an amorphous metal oxide, since there is no crystal structure, diffraction does not occur even when irradiated with an electron beam.

  The metal oxide constituting the dielectric layer is not particularly limited as long as it is a material that can form both a crystal region (crystal grain) and an amorphous region. For example, an oxide of a metal atom (hereinafter also referred to as “first metal atom”) that is easily crystallized, doped with a metal atom having a larger atomic radius than the first metal atom (hereinafter “second metal atom”) (Hereinafter referred to as “first metal oxide”) can be used as the metal oxide. In such a form, an amorphous phase is generated in the vicinity of the second metal atom having a large atomic radius, and a crystal phase (crystal grain) derived from the oxide of the first metal atom can be formed at a position away from the second metal atom.

  Examples of the first metal atom include Zn (zinc), Al (aluminum), Ti (titanium), Ni (nickel), and Mg (magnesium).

  Examples of the second metal atom include metal elements having a large atomic radius such as Sn (tin), In (indium), Nb (niobium), Zr (zirconium) and the like whose atomic number is 40 or later. Only 1 type may be used for a 2nd metal atom, and 2 or more types may be mixed and used for it.

  Preferably, the first metal oxide is capable of forming a crystal region (crystal grain) having a reflection peak on the [311] plane. That is, another embodiment of the present invention provides a dielectric film that includes a metal oxide crystal region and an amorphous region, and the crystal region has a reflection peak on the [311] plane. Such a dielectric film is excellent in radio wave transmission and visible light transmission and is transparent. In the present specification, “transparent” means that Tvis (visible light transmittance) is 70% or more.

  Particularly preferably, the first metal oxide includes tin-doped zinc oxide (ZnSnO) in which Sn (tin) as the second metal atom is doped into an oxide (ZnO) of Zn (zinc) as the first metal atom. . ZnSnO is a dielectric film having a ZnO crystal phase having a reflection peak on the [311] plane as a crystal region and a ZnSnO amorphous phase as an amorphous region, by facing target sputtering (FTS) described later. Can be formed.

  FIG. 8A is an electron beam diffraction image of a ZnSnO film as a dielectric film according to an embodiment of the present invention, measured by a transmission electron microscope (TEM), and the heat obtained in Example 1-1 described later. It is the electron beam diffraction image by TEM of the dielectric material layer in a reflective film. As shown in FIG. 8A, a diffraction pattern derived from a single crystal on the [311] plane is confirmed in the electron beam diffraction image of TEM.

  In addition, since the ratio of an amorphous area | region increases, so that there is much dope amount of the 2nd metal atom in a 1st metal oxide, it is necessary to set it as the dope amount which can obtain a desired crystal region (crystal grain). The doping amount can be appropriately determined according to the type of the first metal atom and the type of the second metal atom. For example, when tin-doped zinc oxide (ZnSnO) is used as the first metal oxide, the Zn: Sn (atomic ratio) is preferably 50:50 to 80:20. When Zn: Sn is 50:50 or more, that is, when the amount of Zn is more than the amount of Sn, it is preferable because the electrical resistivity of the dielectric film increases. On the other hand, when Zn: Sn is 80:20 or less, it is preferable because sufficient visible light transmittance can be secured. In addition, Zn: O is preferably in the range of 1: 0.5 to 1: 1 (atomic ratio) because visible light transmittance is remarkably reduced in a peroxidized state.

  In the dielectric layer according to the embodiment shown in FIG. 4 and FIG. 5, only one kind of first metal oxide, tin-doped zinc oxide (ZnSnO), is used as the metal oxide. Two or more first metal oxides may be mixed. In addition to the first metal oxide, the dielectric layer may further include another metal oxide, for example, a metal oxide that easily crystallizes (second metal oxide).

  By including the second metal oxide together with the first metal oxide, an amorphous phase is formed in the vicinity of the second metal atom of the first metal oxide, and at the same time, the metal atom of the second metal oxide is used as a base point. Formation of a crystal phase (crystal grain) derived from the oxide of the first metal atom of one metal oxide is promoted. Therefore, a larger crystal region (crystal grain) can grow as compared with a dielectric layer (dielectric film) made of only the first metal oxide. The crystal region (crystal grain) whose size has increased in this manner is easily broken, and cracks can be generated from the crystal grain boundary as a base point by stretching the film in the in-plane direction after film formation. Therefore, according to the present embodiment, it is possible to obtain a dielectric layer having a crack as shown in FIGS. 4 and 5, and intentionally generating a crack in the dielectric layer (dielectric film) in this way. Thus, it is possible to further improve radio wave permeability while maintaining visible light transparency. However, as long as radio wave transmission is ensured, the mixed metal system of the first metal oxide and the second metal oxide may of course have no cracks.

The second metal oxide is not particularly limited as long as it is easily crystallographically oriented. For example, aluminum-doped zinc oxide (AZO; Al—Zn—O), zinc oxide (ZnO), titanium oxide (TiO ₂ ), Y -Ba-Cu-O etc. are mentioned, Above all, aluminum doped zinc oxide (AZO) and zinc oxide (ZnO) with high transparency are preferable. That is, in a preferred embodiment, the metal oxide is at least one of tin-doped zinc oxide (ZnSnO) as the first metal oxide and aluminum-doped zinc oxide (ZnAlO) and zinc oxide (ZnO) as the second metal oxide. Including Furthermore, aluminum-doped zinc oxide (AZO) that has particularly good crystal orientation as the second metal oxide is particularly preferable. In such a case, the crystallization of ZnO proceeds from AZO, particularly Al, and a dielectric layer (dielectric film) having a large crystal region size is obtained. The amount of Al doped in AZO is not particularly limited, but it is preferable that Zn: Al (atomic ratio) is 99.9: 0.1 to 90.0: 10.0 from the viewpoint of crystal orientation.

  FIG. 9 is a photograph of a cross section of a mixed film of ZnSnO and ZnAlO as a dielectric layer used in one embodiment of the present invention, observed with a transmission electron microscope (TEM), and is obtained in Example 2-1 described later. 2 is a TEM photograph of a cross section of a dielectric layer in a heat reflecting structure. FIG. 10 is a photograph of the surface of a mixed film of ZnSnO and ZnAlO used as a dielectric layer used in an embodiment of the present invention, observed with an optical microscope, and the heat reflection obtained in Example 2-1 described later. It is an optical microscope photograph of the surface of the dielectric material layer in a structure. FIG. 11 is a schematic diagram of the structure of a mixed film of ZnSnO and ZnAlO as a dielectric layer according to an embodiment of the present invention. As shown in FIG. 9, the dielectric layer is composed of an amorphous region 17a of ZnSnO as a metal oxide and a crystal region 17b of ZnSnO and ZnAlO. Further, as shown in FIG. 10, the dielectric layer 17 has a crack 23. More specifically, as shown in FIG. 11, the crystal region 17b is composed of an Al—Zn—O crystal phase (crystal grains), and the amorphous region 17a is composed of an ZnSnO amorphous phase. As shown in FIGS. 10 and 11, cracks 23 exist in the vicinity of the grain boundaries of the crystal region 17b. FIG. 8F is an electron beam diffraction image of a mixed film of ZnSnO and ZnAlO as a dielectric layer according to the present embodiment, measured by a transmission electron microscope (TEM), and obtained in Example 1-1 described later. It is an electron beam diffraction image by the TEM of the dielectric material layer in the obtained heat reflection film. Also in FIG. 8F, the diffraction pattern derived from the single crystal of [311] plane is confirmed similarly to FIG. 8A.

When the dielectric layer includes the first metal oxide and the second metal oxide, the compounding ratio of the first metal oxide and the second metal oxide is a dielectric composed of a crystalline region and an amorphous region of the metal oxide. There is no particular limitation as long as a body membrane can be obtained. Preferably, the first metal oxide: second metal oxide (weight ratio) is 60:40 to 80:20. As the proportion of the second metal oxide increases, the size of the crystal region (crystal grains) tends to increase. If the crystal grains become too large, the visible light transmittance decreases. Therefore, from the viewpoint of preventing a decrease in visible light transmittance, the ratio of the first metal oxide: second metal oxide (weight ratio) is preferably smaller than 60:40. On the other hand, if the ratio of the second metal oxide is too small, cracks may not occur due to the film stretching process described below. Further, although the detailed mechanism is unknown, visible light transmittance may be lowered if the ratio of the first metal oxide is too large in the mixed system of the first metal oxide and the second metal oxide. Therefore, the first metal oxide: second metal oxide (weight ratio) is more than 80:20 in order to obtain the effect of improving radio wave transmission due to the occurrence of cracks while ensuring visible light transmittance. The ratio is preferably large. More preferably, from the viewpoint of obtaining excellent visible light transmission and radio wave transmission, the first metal oxide: second metal oxide (weight ratio) is 65:35 to 75:25. In addition to the first metal oxide and the metal oxide, other metal oxides (for example, alkali metal, alkaline earth metal, Ti, Ni, Fe , Oxides of transition metals such as Co).

  The form of the crystal region and the amorphous region in the dielectric layer is not particularly limited, but a structure in which the crystal region is dispersed in the amorphous region is preferable. Such a dispersion structure can improve visible light transmission and radio wave transmission. Further, the shape of the crystal region and the amorphous region is not particularly limited. For example, when the crystal region is dispersed in an amorphous region, the dispersion form may be random or aligned, and the crystal region may have a spherical shape, a cylindrical shape, a prismatic shape, a plate shape, a needle shape, etc. Is mentioned.

  The size of the crystal region is not particularly limited as long as visible light transmission and radio wave transmission are ensured. When the crystal region size becomes too large, the visible light transmittance is lowered. Therefore, in order to ensure good visible light transmittance, the crystal region size is preferably 15 nm or less, more preferably 12 nm or less, and further preferably 10 nm or less. Preferably, it is 7.5 nm or less.

  Furthermore, in one embodiment of the present invention, it is preferable that the diameter of the crystal region is 3 nm or less from the viewpoint of achieving particularly excellent visible light transmittance. In addition, electrical resistance is thought to be mainly due to crystal grain boundaries and crystal structures. When the crystal occupancy is the same, the smaller the crystal grains, the larger the area of the grain boundaries and the higher the electrical resistivity. To do. Therefore, when the size of the crystal region is small as described above, the electrical resistivity can be increased by reducing the size of the crystal region, thereby improving the radio wave permeability. More preferably, it is 2.6 nm or less, more preferably 2.0 nm or less, from the viewpoint of increasing electric resistivity and improving radio wave permeability. Such a microcrystalline region can be formed by forming the metal oxide of the dielectric layer from the first metal oxide and forming the dielectric layer (dielectric film) using the FTS method described later. .

  In another embodiment of the present invention, the size of the crystal region is 3 nm to 15 nm, more preferably 4 nm to 12 nm. Such a film having relatively large crystal grains is easy to break, and the dielectric layer is easily stretched in the in-plane direction after film formation as described later, so that the dielectric layer easily has higher electric resistance than the grain boundary. Cracks can be generated, whereby a film excellent in radio wave permeability can be obtained.

  The lower limit of the diameter of the crystal region is not particularly limited, but is preferably 0.5 nm or more. The theoretical resolution of electron beam diffraction of a transmission electron microscope (TEM) is 0.1 nm, but the substantial resolution is 0.5 nm. Therefore, if the diameter of the crystal region is 0.5 nm or more, it can be substantially detected by TEM electron diffraction. In this specification, the “diameter of the crystal region” refers to a projected area circle equivalent diameter (diameter of a circle having the same area as the projected area) of the crystal region in the cross section of the dielectric layer, which is obtained by image analysis of an electron micrograph. . Specifically, all the projected area equivalent circle diameters of the crystal region observed in several to several tens of fields are measured (total N> 100), and a value calculated as an average value thereof is adopted as the diameter of the crystal region. It shall be.

  Moreover, the occupation ratio of the crystal region in the dielectric layer (dielectric film) is not particularly limited, but is preferably 20 to 90% by volume. If it is 20% by volume or more, the effect of increasing electrical resistance due to the presence of crystal grains can be obtained, and radio wave transmission can be improved. On the other hand, if it is 90 volume% or less, the fall of the visible light transmittance by the light scattering in a crystal grain boundary will be suppressed. From the viewpoint of increasing electric resistivity and further improving radio wave permeability, it is more preferably 25% by volume or more, further preferably 30% by volume or more, and particularly preferably 50% by volume or more. Moreover, from a viewpoint of obtaining the outstanding visible light transmittance, More preferably, it is 80 volume% or less, Especially preferably, it is 60 volume% or less. In general, the occupation ratio of the crystal region is small when only the first metal oxide is used as the metal oxide of the dielectric layer, and is large in the mixed system of the first metal oxide and the second metal oxide. Tend.

  In this specification, “occupation ratio of crystal region” refers to the occupied volume of the crystal region in the dielectric layer. In general, the area ratio in a two-dimensional cross section can be treated as a volume ratio in a three-dimensional space. Therefore, in this specification, a crystal region (cumulative area) of a cross-sectional photograph is obtained by binarizing a cross-sectional observation photograph using an electron microscope. The ratio of the entire region (area) is calculated, and this is handled as the occupied volume of the crystal region.

The dielectric layer (dielectric film) preferably has an electric resistivity of 1.0 × 10 ⁻² Ω · cm or more in order to exhibit radio wave permeability. From the viewpoint of further improving radio wave permeability, it is more preferably 0.1 Ω · cm or more, further preferably 1 Ω · cm or more, still more preferably 10 Ω · cm or more, and particularly preferably 20 Ω · cm or more. is there. The upper limit is not particularly limited, but it is preferably 100 Ω · cm or less, more preferably 50 Ω · cm or less, in order to achieve compatibility with transparency. In addition, the electrical resistivity of a dielectric material layer is measured by the 4-probe method based on JISK7194-1994.

  The method for forming the dielectric layer (dielectric film) is not particularly limited as long as it can form both a crystalline region and an amorphous region, but a method using a dry process such as sputtering or vapor deposition is preferable, and sputtering is used. The method is more preferred. In the case of sputtering, since an element decomposed to the atomic level by plasma is deposited on the substrate, a very dense film can be formed. Among these, it is particularly preferable to use a facing target sputtering (FTS) method.

  The opposed target sputtering (FTS) method is strongly applied to an opposed target space formed by applying a perpendicular direct current magnetic field between two targets arranged in parallel at a predetermined interval so as to face each other. This is a sputtering method using constrained plasma. The target material sputtered by the plasma is laminated on a substrate placed outside the plasma constraining space in a direction perpendicular to the target to form a thin film. As described above, in the FTS method, since the substrate is disposed in a plasma-free space, irradiation of high energy particles onto the substrate can be suppressed, and internal stress of the film can be reduced. Therefore, in the film formation by FTS, the crystal phase of the metal oxide is easily aligned. For example, when ZnSnO is used as a target, as shown in FIG. 7, the Sn vicinity having a large atomic radius compared to Zn becomes an amorphous phase due to disorder of the ZnO crystal arrangement, but in a region away from Sn, Formation of ZnO crystal is promoted, and a crystal phase (crystal grain) is formed. As described above, when the FTS method is used, a film having both a crystalline region and an amorphous region can be easily formed. In addition, it is excellent in that a dense film can be obtained and thermal damage to the substrate can be reduced as compared with the conventional sputtering method.

  On the other hand, the conventional magnetron sputtering method is arranged in parallel so that the substrate and the target face each other, and plasma is formed on the surface of the target. It is difficult to form a film having both regions and amorphous regions. For example, in the case where ZnSnO is used as a target, if the crystal arrangement of ZnO is shifted due to Sn, the effect of the deviation is widespread, and a film having the entire amorphous phase (region) 17a as shown in FIG. 12 is formed. FIG. 8B shows an electron diffraction pattern of a ZnSnO film formed by magnetron sputtering, measured by a transmission electron microscope (TEM). FIG. 8B is an electron beam diffraction image of the dielectric layer in the heat reflecting film obtained in Comparative Example 4 described later by TEM. As shown in FIG. 8B, the diffraction pattern derived from the ZnO crystal phase is not confirmed in the TEM electron diffraction pattern of the ZnSnO film formed by the magnetron sputtering method, and it is confirmed that the whole is formed of the amorphous phase. Is done. Such a conventional ZnSnO film functions as a transparent conductive film as described in Patent Document 1, and has low radio wave transmissivity.

  In addition, a wet film formation method such as a sol-gel method is also known, but since a dielectric film formed by a wet process such as a sol-gel method has a small crystal structure, a crystal diffraction pattern is confirmed in an electron diffraction image by TEM. It is difficult to obtain sufficient radio wave permeability. Furthermore, the dielectric film formed by wet film formation has a problem that it is easily influenced by migration of the metal layer because the crystal structure is fine and the film itself is low in density. In order to avoid migration of the metal layer, it is also known to provide a barrier layer having a thickness of 2 nm or less composed of Ni (nickel), Ti (titanium) or the like between the metal layer and the dielectric layer. A manufacturing method becomes complicated and is not preferable.

(Metal layer)
The material (metal) constituting the metal layer 18 is not particularly limited as long as it is a metal that absorbs little in the visible light region. Specifically, gold (Au), silver (Ag), copper (Cu), aluminum (Al), nickel (Ni), or an alloy thereof can be used. The alloy is not particularly limited, and a conventionally known alloy can be used. Preferably, silver (Ag) or aluminum (Al) alone, or an alloy thereof, having a uniform spectrum in the visible light region and no coloration. More preferably, it is a silver (Ag) simple substance or a silver alloy that has particularly small light absorption in the visible light region and a flat spectrum of 300 nm to 800 nm. More preferably, it is an Ag alloy (silver alloy) with high corrosion resistance. As a silver alloy, silver (Ag) added with one or more metals such as aluminum (Al), gold (Au), copper (Cu), palladium (Pd), neodymium (Nd), bismuth (Bi) However, silver alloys such as Ag—Au, Ag—Au—Cu, Ag—Au—Nd, Ag—Bi, and Ag—Pd, which have low absorption in the visible light region, are particularly preferable.

(Transparent substrate film)
The transparent substrate film 16 is not particularly limited as long as it is transparent to visible light (visible light transmission) and can function as a film-forming member of an alternately laminated body.

  Although it does not specifically limit as thickness of a transparent base film, 20-200 micrometers which can respond to a roll-to-roll manufacturing method is preferable, More preferably, it is 20-100 micrometers easy to follow a three-dimensional curved surface etc., More preferably 20-75 μm.

  The material of the transparent substrate film is not particularly limited, but a transparent resin film that is excellent in productivity and advantageous in terms of cost is preferable. Moreover, the heat | fever reflecting structure body which used the transparent resin film as a base material is preferable also at the point which can be used for various uses. Further, even when a laminated glass as shown in FIG. 2 is produced, the heat insulating glass can be easily produced by sandwiching the heat reflecting film into the laminated glass.

  There is no restriction | limiting in particular in a transparent resin film, About the material, a shape, a structure, etc., it can select suitably from well-known things. For example, polyester resin film such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), modified polyester; polyolefin resin film such as polyethylene (PE) resin film, polypropylene (PP) resin, polystyrene resin, cyclic olefin resin; Vinyl resin films such as vinyl chloride and polyvinylidene chloride; polyetheretherketone (PEEK) resin film; polysulfone (PSF) resin film; polyethersulfone (PES) resin film; polycarbonate (PC) resin film; polyamide resin film; Polyimide resin film; acrylic resin film; triacetyl cellulose (TAC) resin film and the like.

  Among them, polyester films such as polyethylene terephthalate (PET) film and polyethylene naphthalate (PEN) film; polyolefin resin films such as polyethylene (PE) resin film, polypropylene (PP) resin film, polystyrene resin film, cyclic olefin resin; nylon Film: Highly transparent film such as (meth) acrylic resin film such as (meth) acrylate film or polynorbornene acrylate film is good, and polyester film or polyolefin film should be included from the viewpoint of transparency, heat resistance, strength and cost. Is preferred. In addition, since the stretched resin film produced by the stretching method has high strength, it can suppress defects such as film breakage that occurs during handling during lamination, and can also suppress the formation of spherical crystals due to heating, resulting in cloudiness. Since it is suppressed, it is preferable.

  As the transparent substrate film 16, the transparent resin film may be used alone, or two or more sheets may be stacked. Under the present circumstances, the kind of transparent resin film may be the same, and may differ.

  As a particularly preferred embodiment, the transparent resin film is a multilayer film formed by alternately laminating a plurality of layers having different refractive indexes. More preferably, it is a dielectric multilayer film having a reflection peak in the near infrared region with a wavelength of 800 nm to 1200 nm. Such a multilayer film is excellent in reflection characteristics in the near-infrared region having a wavelength of 800 nm to 1200 nm. An electromagnetic wave having a wavelength range of 800 nm to 1200 nm is easily converted into vibrational energy of molecules, atoms, and electrons when irradiated on a substance, and the kinetic energy is converted into heat, which causes the temperature to rise. As described above, an alternating laminate composed of a metal layer and a dielectric layer has excellent reflection characteristics of electromagnetic waves (middle infrared light) having a wavelength range of 1000 nm or more, but transmits electromagnetic waves in the wavelength range of 800 nm to 1000 nm. It's easy to do. Therefore, by using a dielectric multilayer film as a transparent substrate film, the reflective performance in the near infrared region where the rising of the reflection spectrum is seen in the alternate laminate 19 can be complemented, and the heat insulation effect can be further improved. .

  FIG. 13 shows a basic configuration of a multilayer film as a transparent substrate film used in one embodiment of the present invention. In the form shown in FIG. 13, the transparent base film 16 is formed by alternately laminating two types of dielectric films (161, 162) having different refractive indexes. However, the multilayer film is not limited to such a form, and three or more kinds of dielectric films having different refractive indexes may be used.

  Each dielectric film constituting the multilayer film may be composed of a single material or may be composed of a combination of different types of materials. Specifically, a multilayer film formed by alternately laminating a plurality of transparent resin films having different refractive indexes, a multilayer film formed by alternately laminating layers composed of an inorganic dielectric material on the transparent resin film, A multilayer film formed by alternately laminating layers made of an inorganic dielectric material and transparent resin films on the transparent resin film can be used.

  It does not restrict | limit especially as a transparent resin film which comprises a multilayer film, What was mentioned above can be used preferably. In addition, inorganic dielectric materials constituting the multilayer film include silicon oxide, titanium oxide, niobium oxide, zinc oxide, aluminum oxide, calcium fluoride, magnesium fluoride, indium tin oxide (ITO), and antimony tin oxide (ATO). And tin-doped zinc oxide. Note that the dielectric material is not limited to a perfect insulator, and may have a slight conductivity and a slight infrared absorption property such as ITO or ATO. These may be used individually by 1 type and may be used in combination of 2 or more type.

  Among them, the multilayer film is preferably formed by alternately laminating a plurality of transparent resin films having different refractive indexes.

  As the difference in refractive index between the dielectric films constituting the multilayer film increases and the number of laminated layers increases, electromagnetic waves can be continuously reflected with high reflectivity. From such a viewpoint, the difference in refractive index between adjacent dielectric films is preferably 0.05 to 1. Generally, when producing the said multilayer film, the refractive index difference of a dielectric film is about 0.1-0.2. The number of stacked layers may be several hundred to several thousand layers, preferably 200 to 400 layers. In such a case, it is possible to obtain a desired reflectance and reflection area.

  The film thickness of the dielectric film constituting the multilayer film can be determined according to the Bragg reflection equation according to the target reflection region. By sequentially solving the Bragg reflection equation for each layer, it is possible to design a laminated film that reflects an arbitrary wavelength.

  The thickness of each layer of the dielectric films (16a, 16b) obtained according to the Bragg reflection equation increases or decreases in the stacking direction, but the thicker one may be arranged on the side of the alternately stacked body 19, You may arrange | position the one where thickness is smaller to the alternate laminated body 19 side.

  The total thickness of each layer is the thickness of the multilayer film. However, in order to obtain a desired film thickness, a thickness adjusting layer that does not cause electromagnetic wave interference can be added. The thickness adjusting layer is usually formed from a dielectric film.

  The method for producing a multilayer film formed by laminating dielectric films is not particularly limited. When a thermoplastic resin is used as the dielectric, for example, by using a coextrusion method, it is possible to easily make a laminated film of several hundred layers or more. On the other hand, when an inorganic dielectric material is used as a dielectric, for example, sputtering, vapor deposition, or a sol-gel method by applying a precursor is used on a transparent resin film as a substrate, and the layers are sequentially laminated. You can do it.

  In the laminated glass 1 of this embodiment, the 1st glass plate 11 is normally arrange | positioned at the vehicle outer side of the motor vehicle which electromagnetic waves, such as a sunlight ray, inject, and the 2nd glass plate 15 is arrange | positioned indoors. Here, when the laminated glass 1 is configured using the heat reflecting film 13 using the multilayer film as the transparent substrate film 16, the transparent substrate film 16 is the first incident side of electromagnetic waves such as sunlight. It is preferable to arrange between the glass plate 11 and the alternate laminate 19. That is, it is preferable to arrange the alternate laminate 19 so as to be adjacent to the second intermediate layer on the indoor side so that the transparent base film 16 is adjacent to the first intermediate layer. Thereby, the electromagnetic wave can be prevented from entering the alternating laminate 19 and the second intermediate layer 14 behind the multilayer film as the transparent substrate film 16. Furthermore, it is possible to suppress the electromagnetic wave reflected by the alternate laminate 19 from being reflected again by the multilayer film and transmitted to the indoor side, and as a result, it is possible to effectively prevent the temperature rise in the room.

(Glass plate)
It does not specifically limit as the 1st glass plate 11 and the 2nd glass plate 15, What is necessary is just to select according to the light transmission performance and heat insulation performance which are requested | required for a use, and it may be inorganic glass or organic glass. .

  The inorganic glass plate is not particularly limited, and examples thereof include various types of inorganic glass such as float plate glass, polished plate glass, mold plate glass, meshed plate glass, wire-containing plate glass, heat ray absorbing plate glass, and colored plate glass.

  Examples of the organic glass include polyester resins such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and modified polyester; polyolefin resins such as polyethylene (PE) resin, polypropylene (PP) resin, polystyrene resin, and cyclic olefin resin; Vinyl resins such as vinyl chloride and polyvinylidene chloride; polyether ether ketone (PEEK) resin; polysulfone (PSF) resin; polyether sulfone (PES) resin; polycarbonate (PC) resin; polyamide resin; An acrylic resin such as: a glass plate made of triacetyl cellulose (TAC) resin or the like. These organic glass plates may be a laminate formed by laminating a plurality of sheet-shaped ones made of the resin.

  Regarding the color, not only the transparent glass plate but also glass plates of various colors such as general-purpose green, brown and blue used for vehicles and the like can be used. The first glass plate 11 and the second glass plate 15 may be the same type of glass plate or different types of glass plates.

  However, it is desirable that the first glass plate 11 disposed on the outdoor side is difficult to absorb visible light or infrared light. Preferably, the glass has an electromagnetic wave absorption of less than 5% and a visible light transmittance of 85% or more. Specifically, the glass has an electromagnetic wave absorption of 750 nm or more of less than 5% and a transmittance of 380 nm to 780 nm of 85% or more. Is preferred. If glass that absorbs heat rays such as visible light or infrared rays is used on the outdoor side, the indoor temperature may increase due to re-radiation of the absorbed heat. Specifically, it is preferable to use clear glass or the like.

  On the other hand, the second glass plate 15 arranged on the indoor side is not particularly limited, and may absorb visible light or infrared light. Since the conductive film 15 (particularly, the heat insulating layer 13) is arranged on the vehicle exterior side of the second glass plate 15, and the infrared rays are blocked by this, the infrared absorption amount of the second glass plate 15 can be reduced. This is because the influence of radiation is small. Specifically, it is preferable to use green glass in addition to clear glass. Among these, it is preferable to use green glass because it has ultraviolet absorption performance.

  There is no restriction | limiting in particular about the thickness of a glass plate, What is necessary is just to set suitably according to a use. In general, the glass plate has a thickness of 1.5 to 2.5 mm. For example, in the use of a windshield (window shield) of a transportation vehicle, the glass plate generally has a thickness of 2.0 to 2.3 mm. It is preferable to use a plate.

  In addition, although the laminated glass 1 of embodiment shown in FIG. 2 contains two glass plates (the 1st glass plate 11 and the 2nd glass plate 15), in the laminated glass 1 which concerns on this form, it is 3 or more sheets. A glass plate may be included. Even when three or more glass plates are included, the laminated body may be bonded and integrated into a laminated glass by interposing an intermediate layer between the glass plates, as in FIG.

(Middle layer)
The intermediate layers (12, 14) are interposed between two or more glass plates and have a function of bonding and integrating them. Since the laminated body constituting the laminated glass is strongly bonded by the intermediate layer, it is possible to impart excellent penetration resistance, impact resistance, and scattering prevention effects to the laminated glass.

  The intermediate layer is not particularly limited as long as it is a resin film that is generally used as an intermediate layer of laminated glass, and it is preferable that there is no absorption due to a functional group other than an OH group in the visible light region or the infrared light region. . Specifically, the intermediate layer is usually formed from a polyvinyl butyral resin (PVB resin) or an ethylene-vinyl acetate copolymer resin (EVA resin), and includes an ultraviolet absorber, an antioxidant, an antistatic agent, Heat stabilizers, lubricants, fillers, coloring, adhesion regulators, and the like may be added and blended as appropriate. These resins may be used alone or in combination of two or more.

  The intermediate layer may be manufactured using a known method, but a commercially available product may be used. Examples of commercially available products include plasticized PVB manufactured by Sekisui Chemical Co., Ltd. and Mitsubishi Monsanto, EVA resin manufactured by DuPont and Takeda Pharmaceutical Company Limited, and modified EVA resin manufactured by Tosoh Corporation.

  The intermediate layer may be composed of a single layer of the resin film, or may be used in a state where two or more layers are laminated. Moreover, the 1st intermediate | middle layer 12 and the 2nd intermediate | middle layer 14 may be comprised from the same kind of resin, and may be comprised from a different kind of resin.

  The intermediate layer may contain fine particles of a transparent conductive oxide material having heat ray absorption ability such as indium tin oxide (ITO) and antimony tin oxide (ATO), but it is preferable not to contain these fine particles. This is because these fine particles absorb heat once and then radiate heat indoors by re-radiation, resulting in an increase in the temperature of the room over time. From this point of view, when these fine particles are dispersed, it is preferably applied to the second intermediate layer disposed on the indoor side. In the second intermediate layer, most of the heat rays are blocked by the conductive film, so that the influence of re-radiation by the fine particles can be minimized and the heating efficiency in winter can be increased.

  It does not restrict | limit especially as a method of producing the laminated glass of this invention, What is necessary is just to use the manufacturing method of a general laminated glass. Specifically, the laminated glass of the present embodiment remained after pre-adhesion after the heat reflecting film 13 and the intermediate layers (12, 14) were laminated between the glass plates (11, 15) and pre-adhered. It can be manufactured by a process of removing bubbles by pressure bonding (main bonding) at high temperature and pressure.

  The laminated glass 1 can be continuously manufactured, and since a film needs to be attached according to each glass, a heat reflecting plate in a form in which a heat reflecting film manufactured in a batch type is attached to the glass. This is advantageous in terms of cost. Further, since the heat reflecting film 13 is sandwiched between the pair of glass plates (11, 15) via the intermediate layers (12, 14), the heat reflecting film 13 is prevented from being damaged or peeled off. In particular, when the glass with the heat reflection film attached is used for the windshield of an automobile, the use of a wiper or the like makes the heat reflection film peeled off or scratched, and the surface was covered with a hard coat layer. Even in this case, it is difficult to satisfy long-term durability. Furthermore, since the laminated glass 1 has a form in which the heat reflecting film 13 containing a metal is sealed by the intermediate layer, rust due to intrusion of moisture into the heat reflecting film 13 (particularly the metal layer) is prevented, Excellent durability.

[Second Embodiment]
The heat reflecting film 13 is used for the laminated glass shown in FIGS. 1 and 2, and is attached to a facility (substrate) that is exposed to sunlight for a long period of time, such as an outdoor window of a building or an automobile window. It is used mainly for the purpose of improving weather resistance as a film for window pasting such as a heat ray reflective film for imparting odor.

  FIG. 14 is a schematic cross-sectional view showing the basic configuration of the heat reflecting plate 20 of one embodiment of the present invention. A heat reflecting plate 20 shown in FIG. 14 includes a substrate 21 and a heat reflecting film 13 located on the substrate 21. The heat reflecting plate 20 in this form is excellent in heat ray reflectivity, visible light transmittance, and radio wave transmittance.

  In the present embodiment, the heat reflecting film 13 and the substrate 21 are bonded via the adhesive layer 22. Note that the heat reflecting film 13 and the substrate 21 may be directly bonded without interposing the adhesive layer 22. In the heat reflecting plate 20 shown in FIG. 14, the heat reflecting film 13 is attached to only one surface of the substrate 21, but the heat reflecting film 13 may be provided on both surfaces of the substrate 20.

  The heat reflecting plate 20 shown in FIG. 14 is different from the heat reflecting film 13 shown in FIG. 3 in that a substrate 21 and an adhesive layer 22 are arranged in addition to the heat reflecting film 13. Since the configuration other than this is the same as that of FIG. 3, the description thereof is omitted.

  As the adhesive layer, a resin film such as PVB resin or EVA resin used as the intermediate layer (12, 14) of the laminated glass 1 may be used. In addition, you may comprise including a photocurable resin and a thermosetting resin. The adhesive preferably has durability against ultraviolet rays, and it is preferable to use an acrylic pressure-sensitive adhesive or a silicone pressure-sensitive adhesive. In the adhesive layer, an ultraviolet absorber, an antioxidant, an antistatic agent, a heat stabilizer, a lubricant, a filler, a coloring agent, an adhesion adjusting agent, and the like may be appropriately added and blended.

  In the present embodiment, the heat reflection film 13 is attached to the substrate 21 via the adhesive layer 22 on the surface on the alternating laminate 19 side. In such a form, the transparent substrate film 16 is preferably a multilayer film formed by alternately laminating a plurality of layers having different refractive indexes as shown in FIG. In such a case, the electromagnetic wave can be prevented from entering the alternating laminate 19 behind the multilayer film, and the electromagnetic wave reflected by the alternating laminate 19 can be prevented from being reflected again by the multilayer film and transmitted to the indoor side. As a result, it is possible to effectively prevent the temperature rise in the room. However, this invention is not limited to such a form, The heat | fever reflection film 13 may be affixed on the board | substrate 21 by the surface at the side of the transparent base film 16. FIG.

  The substrate 21 is not particularly limited as long as the substrate 21 is transparent to visible light (visible light transmission) and can serve as a film-forming member of an alternately laminated body. It is a board.

  The material in particular of a glass plate is not restrict | limited, The inorganic glass and organic glass which were illustrated as a constituent material of the glass plate (11, 15) of the said laminated glass 1 are mentioned. The thickness of the substrate is not particularly limited and is selected according to the application. For example, in automotive glass applications, a thickness of 1.5 to 5.0 mm is preferable and 2.0 to 5.0 mm is more preferable from the viewpoint of securing mechanical strength.

  The heat reflecting plate 20 may have a further layer in addition to the substrate 21, the adhesive layer 22, and the heat reflecting film 13. For example, since the surface of the heat reflecting film 13 is exposed to the outside in the heat reflecting plate 20 of this embodiment, the surface of the alternate laminated body 19 is easily damaged compared to the laminated glass 1 as described above. Therefore, the surface of the heat reflecting film 13 may be covered with a hard coat layer for the purpose of improving durability.

[Third Embodiment]
In still another embodiment of the present invention, the base material is a substrate, and in such a case, the heat reflecting structure functions as a heat reflecting plate. FIG. 15 is a schematic cross-sectional view showing a basic configuration of a heat reflecting plate according to an embodiment of the present invention. As shown in FIG. 15, the heat reflecting plate 20 includes a substrate 21 and an alternate stacked body 19 positioned on the substrate 21. The alternate laminate 19 is formed by alternately laminating metal layers 18 and dielectric layers 17, and the dielectric layers 17 are disposed on both outermost layers. The dielectric layer includes a metal oxide crystal region and an amorphous region. By setting it as this structure, the heat | fever reflecting plate excellent in heat ray reflectivity, visible light transmittance | permeability, and radio wave transmittance is obtained.

  The heat reflecting plate 20 shown in FIG. 15 is different from the heat reflecting film 13 shown in FIG. 3 in that a substrate 21 is disposed instead of the transparent base film 16. Since the configuration other than this is the same as that of FIG. 3, the description thereof is omitted.

  The substrate 21 is not particularly limited as long as the substrate 21 is transparent to visible light (visible light transmission) and can serve as a film-forming member of an alternately laminated body. It is a board. As the glass plate, the above-described inorganic glass or organic glass can be preferably used.

  The heat reflecting plate 20 may have additional layers in addition to the substrate 21 and the alternating laminate 19.

  For example, for the purpose of further enhancing the heat insulation effect, a multilayer film formed by alternately laminating a plurality of layers having different refractive indexes as described above may be provided. At this time, the multilayer film may be disposed on the surface of the substrate 21, between the substrate 21 and the alternate laminate 19, or on the surface of the alternate laminate 19. It is preferable to arrange a multilayer film on the incident side. Usually, the heat reflecting plate 2 is arranged such that the alternate laminate 19 is located on the incident side of electromagnetic waves such as sunlight and the substrate 20 is located on the indoor side, so that a multilayer film is arranged on the surface of the alternate laminate 19. It is preferable. According to such a form, it is possible to prevent the electromagnetic waves from entering the alternating laminate 19 and to prevent the electromagnetic waves reflected by the alternating laminate 19 from being reflected again by the multilayer film and transmitted to the indoor side. It is possible to effectively prevent the temperature rise in the room.

  In addition, an adhesive layer may be interposed between the alternating laminate 19 and the substrate 21. The form of the adhesive layer is the same as the adhesive layer described in the second embodiment.

  Moreover, since the surface of the alternating laminated body 19 is exposed outside, the surface of the alternating laminated body 19 is easily damaged compared with the laminated glass 1 as described above. Therefore, the surface of the alternate laminate 19 may be covered with a hard coat layer for the purpose of improving durability.

[Method of manufacturing heat reflecting structure]
The method for producing the heat reflecting structure (heat reflecting film 13 and heat reflecting plate 20) of the present invention is not particularly limited, and dielectric layers composed of metal layers and metal oxides are alternately laminated on a substrate. Thus, it is manufactured by forming an alternate laminate. However, it is necessary to use a method in which the dielectric layer 17 can form both the crystalline region 17b and the amorphous region 17a, and it is preferable to form the dielectric layer by the above-described facing target sputtering (FTS) method. .

  The formation method of the metal layer 18 is not particularly limited, and can be formed by a sputtering method such as an FTS method or a magnetron sputtering method or a vapor deposition method.

  Preferably, both the dielectric layer 17 and the metal layer 18 are formed by the FTS method. That is, in the method for manufacturing a heat reflecting structure according to an aspect of the present invention, a sputtering unit that constrains plasma in a facing space by applying a magnetic field in a facing direction between a pair of targets that are arranged to face each other at a predetermined interval. Thus, a step of forming an alternate laminate by alternately laminating metal layers and dielectric layers made of metal oxides on the substrate is included. In such a case, the metal layer and the dielectric layer can be alternately laminated. Furthermore, the FTS method can form a stable film that is not easily oxidized as compared with a conventional method such as magnetron sputtering. Therefore, in particular, when the heat reflecting structure has cracks in the dielectric layer as shown in FIG. 4, migration of metal atoms due to oxidation is preferably suppressed by forming the metal layer by the FTS method.

  As an apparatus suitable for the continuous production of such a heat reflecting structure (particularly, the heat reflecting film 13), for example, the apparatus described in JP-A-2006-334787, that is, the apparatus shown in FIGS. Is mentioned. Hereinafter, a method for manufacturing the heat reflecting structure of the present invention will be described with reference to FIGS. FIG. 16 is a schematic diagram showing a configuration of a roll-to-roll type opposed target sputtering apparatus used in an embodiment of the present invention. FIG. 17 is a schematic perspective view showing the basic configuration of a box-type sputtering unit in the opposed target sputtering apparatus shown in FIG.

  As shown in FIG. 16, this apparatus is configured to continuously form a film while a long film 60 of a substrate is conveyed by roll-to-roll. The vacuum chamber 30 is composed of roll chambers 31 and 32 at both ends and a sputtering chamber 33 located in the middle. The vacuum chamber 30 has a gas supply system 40 for supplying sputtering gas and the like and an exhaust system 41 for exhausting the interior of the chamber. It is connected. The exhaust system 41 is connected to both roll chambers 31 and 32 to shorten the exhaust time. Although not shown, a partition valve is provided between the roll chambers 31 and 32 and the sputtering chamber 33 so that the chambers can be shut off. As a result, the sputtering chamber 33 can be maintained in vacuum even when the roll is replaced, so that oxidation of the target surface and the like are prevented, and there are significant effects in terms of productivity, quality, and maintenance.

  The roll chambers 31 and 32 are provided with roll attaching shafts 34 and 35 of a winding / unwinding machine (not shown), and a film roll 60a of a substrate film 60 is set on the one roll attaching shaft 34. A winding core (not shown) for winding the film 60 is set on the other roll attaching portion 35. That is, the film 60 is unwound from the film roll 60a and conveyed through the sputter chamber 33, where a desired functional film is deposited and wound up again on the film roll 60b. At this time, a tension detector 36 for detecting the tension of the film 60 is installed in the transport path of the film 60, and the roll attachment shaft 34 is wound and unwound by a tension signal from the tension detector 36. The sending torque is controlled by a controller (not shown) comprising a computer. A speed detector 37 for detecting the transport speed of the film 60 is also installed in the transport path of the film 60, and based on the speed signal of the speed detector 37, the roll attachment shaft 35 is wound and unwound. The winding speed is controlled by a controller (not shown) comprising a computer. Thus, the film 60 can be conveyed in both directions at a set constant speed and constant tension. Reference numeral 38 in FIG. 16 denotes a freely rotating free roll having a length equal to or greater than the width of the film 60 forming the transport path of the film 60. The free roll 38 is arranged so as to guide the film 60 so that the film 60 faces the opening of each box-type sputter unit 50, 51, 52 as shown in the drawing and travels in the air in the film formation area in front of the film-type sputtering unit 50, 51, 52. Has been. The sputter chamber 33 only needs to be able to store the free roll 38 that forms the transport path of the film 60. Therefore, the volume of the sputter chamber 33 can be reduced with a very simple configuration, and there is a great effect in terms of equipment cost.

  The sputter chamber 33 is provided with three box-type sputter units 50, 51 and 52 so that a transparent heat insulating film made of three or more laminated films can be manufactured with high productivity. The number of box-type sputter units is selected according to the purpose because it relates to productivity, equipment cost, and the like.

  As shown in FIG. 17, the box-type sputtering unit has target portions 100a and 100b. The target portions 100a and 100b are airtightly attached to the left and right opposing side surfaces 151a and 151b in the figure of the rectangular parallelepiped frame 151. Further, in the figure facing the film 60 of the substrate of the frame body 151, the side surfaces 151c to 151e other than the lower opening side surface 151f (the front side and back side surfaces 151c and 151d are not shown in the drawing) are shielding plates 152c to 152e. (The shielding plate 152c on the front side surface 151c in the figure is not shown) and is airtightly shielded. Accordingly, the box-type unit has a box-type configuration in which only the opening side surface 151f is opened and the other is sealed.

Permanent magnets 130a, 130b, 180a, and 180b are attached to the target portions 100a and 100b. The permanent magnets 130a and 130b are used to form an opposing mode magnetic field in an opposing direction perpendicular to the target surface and a magnetron mode magnetic field parallel to the target surface at the periphery of the target. The permanent magnets 180a and 180b are used to adjust the magnetron mode magnetic field. The permanent magnets 130a, 130b and 180a, 180b are fixed in the storage portion by using fixing plates 132a, 132b and 182a, 182b, respectively. Pole plates 191a and 191b for magnetically coupling the permanent magnets 130a and 130b and the permanent magnets 180a and 180b are installed on the back surfaces of the target portions 100a and 100b. The pole plates 191a and 191b are provided with openings 193a (not shown) and 193b for allowing a cooling water supply pipe and a drain pipe to pass therethrough. In front of the target portions 100a and 100b (in the present specification, the front means the inner direction of the facing surface of the facing target, and the rear means the outer direction of the opposite surface), respectively. A tubular electrode (not shown in the figure for the main body) to be described later is installed for absorption. Leg portions 201b and 201c (201c not shown) of the tubular electrodes are drawn from the shielding plate 152e. Two targets 100a ₁ , 100a ₂ ; 100b ₁ , 100b ₂ (100b ₂ is not shown) are attached to the opposing surfaces of the target portions 100a, 100b in the width direction of the film 60 of the substrate.

In the box-type unit, targets 110a ₁ and 110b ₁ , 110a ₂ and 110b ₂ (110b ₂ is not shown) face each other at a predetermined interval, and a magnetic field in a facing mode perpendicular to the target is formed in the entire target area. The configuration of the plasma constraining magnetic field is known in Japanese Patent Laid-Open Nos. 10-330936 and 10-8246. In addition, a magnetron mode magnetic field parallel to the target surface is formed near the periphery of the target surface along the periphery of the target surface. Therefore, a predetermined sputtering gas such as argon is introduced into the vacuum chamber 30 from the gas introduction system 40, and the sputtering power source is connected to the appropriate location using the tank wall 30d of the vacuum chamber 30 as an anode and the target portions 100a and 100b as cathodes. Sputter deposition is performed by supplying sputtering power. At this time, in the opposing space 120 between the composite targets (110a ₁ + 110a ₂ ) and (110b ₁ + 110b ₂ ) (110b ₂ not shown) of the target units 100a and 100b having the magnetic field generating means 130a and 130b, A high density plasma is formed over the entire surface of the target. Therefore, in the box-type counter target sputtering apparatus having a box-type unit that shields the five side surfaces excluding the opening side surfaces, the sputtered particles are exhausted to high vacuum by the exhaust system 41 through the openings. And deposited on the film 60 of the substrate disposed facing the opening, thereby forming a thin film.

  In addition, the apparatus used for the manufacturing method of the heat | fever reflection structure of this invention is not necessarily limited to the apparatus shown in FIG.16 and FIG.17, The opposing direction of a pair of target arrange | positioned at predetermined intervals Any device may be used as long as it includes a sputtering unit that applies a magnetic field to the opposite space to constrain plasma in the opposing space.

  For example, when the heat reflecting film 13 having the form shown in FIG. 3 or FIG. 4 is manufactured using the facing target sputtering apparatus shown in FIG. A metal material target is set in the middle box-type sputter unit 51 and a metal oxide target is set in the box-type sputter units 50 and 52 at both ends. Thereby, an alternate laminated body having a laminated structure of dielectric layer 17 / metal layer 18 / dielectric layer 17 can be manufactured in one pass. Moreover, the alternating laminated body 19 of the 5 layer structure shown in FIG. 3 or FIG. 4 can be manufactured by reciprocating once. The number of reciprocations is determined according to the number of layers of the alternating laminate 19. Thus, the dielectric layers 17 made of the metal layers 18 and the metal oxides are alternately laminated on the transparent substrate film 16 as the substrate by reciprocating the film according to the number of the laminated layers 19. By doing so, an alternate laminate can be formed.

  As the target, a compound that can generate a material (metal oxide or metal) constituting each layer may be used as the target.

  As a target material for the metal layer 18, a metal material (single member) or a metal alloy material which is a constituent material of the metal layer may be used as a target as it is. As the sputtering atmosphere, air, oxygen, an inert gas containing nitrogen (nitrogen, helium, argon, or the like), or a vacuum can be used.

  The target of the dielectric layer is not particularly limited as long as it is a material capable of generating an amorphous region and a crystalline region of the metal oxide, and examples thereof include a metal oxide or a simple substance or an alloy of a metal. It is determined as appropriate according to the type of metal oxide constituting the layer. However, it is preferable to use a metal oxide as a target because crystallization of the metal oxide is easily affected by oxygen. That is, when the metal oxide is composed only of the first metal oxide, the first metal oxide is used as the target, and the metal oxide further includes the second metal oxide in addition to the first metal oxide. In some cases, it is preferable to use a first metal oxide and a second metal oxide as targets.

  Further, in order to minimize the influence of oxygen, the sputtering atmosphere is preferably an inert gas (nitrogen, helium, argon, etc.) that does not contain oxygen or a vacuum, and is preferably a vacuum. The sputtering pressure at this time is not particularly limited, but is preferably 0.05 Pa to 1 Pa, and more preferably 0.1 Pa to 0.5 Pa. Furthermore, in order to control the crystallization of the metal oxide, the oxygen concentration of the sputtering gas used for sputtering is preferably 1% or less.

For example, when the dielectric layer 17 is composed of tin-doped zinc oxide (ZnSnO) as shown in FIGS. 6 and 7, ZnSnO is used as the metal oxide target, and sputtering of ZnSnO is performed under vacuum. It is preferable to use a sputtering gas having a concentration of 1% or less. That is, in the method of manufacturing a heat reflecting structure according to one preferred embodiment of the present invention, the dielectric layer is formed using a target containing ZnSnO and using a sputtering gas having an oxygen concentration of 1% or less under vacuum. Is done. By performing sputtering under vacuum, the oxidation of ZnSnO is suppressed, and a structure in which crystal regions are dispersed in an amorphous region is obtained. When oxygen is present in the sputtering atmosphere, crystallization tends to occur, the crystal grains become coarse, and ZnSnO microcrystals tend not to be obtained. More preferably, the oxygen concentration in the sputtering gas is preferably 0.5% or less, more preferably 0.1% or less, still more preferably 0.01% or less, and particularly preferably 0. %, That is, an atmosphere in which no oxygen is present. The sputtering gas is not particularly limited, and an inert gas such as argon (Ar) gas or nitrogen (N ₂ ) gas can be used. A mixed gas of argon gas and hydrogen gas (mixing volume ratio Ar: H ₂ = 100: 0 to 97: 3) is also preferable. By mixing hydrogen gas, oxygen atoms are trapped by collision between oxygen and hydrogen in the system, and the concentration of oxygen that can exist in a minute amount in the carrier gas can be reduced.

  Further, for example, as shown in FIGS. 9 to 11, the dielectric layer 17 includes tin-doped zinc oxide (ZnSnO) as the first metal oxide and aluminum-doped zinc oxide (ZnAlO) as the second metal oxide. In the case of including at least one of zinc oxide (ZnO), the film forming step includes tin-doped zinc oxide (ZnSnO), at least one of aluminum-doped zinc oxide (ZnAlO) and zinc oxide (ZnO). Use a target. Thus, by simultaneously sputtering a plurality of metal oxides (first metal oxide, second metal oxide) using a plurality of metal oxide targets, the first metal oxide and the second metal oxide A mixed film is formed. More specifically, in the simultaneous sputtering of the first metal oxide and the second metal oxide by the FTS method, an amorphous phase is formed in the vicinity of the second metal atom of the first metal oxide. At the same time, the formation of a crystal phase (crystal grain) derived from the oxide of the first metal atom of the first metal oxide is promoted starting from the metal atom of the second metal oxide. Also in the sputtering, if oxygen is present in the sputtering atmosphere, crystallization tends to proceed too much and it is difficult to obtain ZnSnO microcrystals, and the oxygen concentration in the sputtering gas is preferably set to the above-described range.

  When simultaneously sputtering multiple metal oxides (first metal oxide, second metal oxide), the ratio of each metal oxide in the mixed film correlates with the power ratio applied to each target, so the power ratio is adjusted. By doing so, the composition of the mixed film can be adjusted. For example, in the case where the sputtering apparatus has an electric energy of 1000 W and a film is formed with a composition of ZnSnO: ZnAlO = 7: 3 (weight ratio), 700 W power may be distributed to the ZnSnO target and 300 W to the ZnAlO target.

  In the mixed system of the first metal oxide and the second metal oxide, a larger crystal phase (crystal grain) grows than a dielectric layer (dielectric film) composed only of the first metal oxide. A film having such a large crystal phase is easily broken. Therefore, a crack can be easily generated in the dielectric layer by extending the alternately laminated body including the formed dielectric layer in the in-plane direction. That is, in the method of manufacturing a heat reflecting structure according to a preferred embodiment of the present invention, after the step of forming the film, a step of generating cracks in the dielectric layer by extending the alternate laminated body in an in-plane direction. It has further.

  The method for extending the alternating laminate in the in-plane direction is not particularly limited. For example, a method of stretching in the in-plane direction using a conventionally known film stretching apparatus; a base material constituting the alternating laminate is heated. Examples include a method in which a dielectric layer or a metal layer is stretched in the in-plane direction by expanding and stretching the base material by expansion; a method in which the alternating laminate is stretched in the in-plane direction by pressing. When the laminated glass 1 is formed using the heat reflecting film 13, the alternately laminated body is formed by pressure bonding after the heat reflecting film 13 and the intermediate layer (12, 14) are laminated between the glass plates (11, 15). Both the dielectric layer 17 and the metal layer 18 constituting 19 are cracked together. Thereby, the crack penetrated in the thickness direction as shown in FIG. 4 is generated.

  The stretch ratio when the alternating laminate is stretched in the in-plane direction is not particularly limited, but preferably, the stretch (stretching) ratio in the width direction (TD direction) and / or the longitudinal direction (MD direction) is 1.005. -1.01 times. When it is 1.01 times or less, that is, when the dimensional change is 1% or less, it can be suppressed that the crack width becomes large and the transparency is lowered. On the other hand, if it is 1.005 times or more, that is, if the dimensional change is 0.5% or more, cracks may occur in the dielectric layer. In addition, when extending | stretching by heat-processing the base material which comprises an alternating laminated body, although the heating temperature of a base material is based also on the kind of base material, it is preferable to heat at 120-140 degreeC normally. Moreover, when extending | stretching by the crimping | compression-bonding process in the case of laminated glass forming, crimping | compression-bonding conditions are not restrict | limited, However, It is preferable to make it crimped by the pressure of 1-1.5 MPa under the temperature of 120-140 degreeC.

  In order to obtain a form in which the dielectric layer has cracks as shown in FIGS. 4 and 5, it is preferable to use a combination of the first metal oxide and the second metal oxide as the metal oxide. As described above, when the dielectric layer is formed by the FTS method using only the first metal oxide, it is usually difficult to obtain very large crystal grains by growing very fine crystal grains in the amorphous phase. Even if such a dielectric layer composed of microcrystalline grains and an amorphous phase is stretched, it is difficult to disperse stress and cause cracks.

  The manufacturing method of the heat reflecting plate 20 is not particularly limited. For example, a heat reflecting plate having the form shown in FIG. 14 can be manufactured by sticking the heat reflecting film 13 formed by the same method as described above to a glass plate using an adhesive. Alternatively, the dielectric layer 17 and the metal layer 18 are directly laminated on a glass plate using a box-type sputtering unit similar to that shown in FIG.

  Also, the method for producing the transparent dielectric film is not particularly limited, and the film may be formed using the FTS method in the same manner as the method for producing the dielectric layer. In the case of a form having cracks as shown in FIG. 5, the formed dielectric film may be stretched in the in-plane direction in the same manner as the above-described alternate laminate stretching method.

  In addition, in the laminated glass for window shields for automobiles, it is important that Tvis (visible light transmittance) determined by safety standards is 70% or more. On the other hand, the heat insulating property is indicated by an index called Tts (solar heat acquisition rate), and is preferably lower in terms of energy saving. Specifically, Tts (sunlight acquisition rate) is preferably 50% or less, and more preferably 45% or less. In particular, when Tvis ≧ 70% and Tts ≦ 45%, the energy saving effect is remarkably improved.

  Hereinafter, although the effect by this invention is demonstrated using an Example and a comparative example, the technical scope of this invention is not limited to these Examples.

[Examples 1-1 to 1-3]
1. Production of Heat Reflective Film A heat reflective film having a seven-layer structure of the alternating laminate 19 in the form shown in FIG. 3 was produced using the box type opposed target sputtering apparatus shown in FIG. In the opposed target sputtering apparatus shown in FIG. 16, among the three box-type sputtering units 50, 51, 52, the box-type sputtering units 50 and 52 located on the left side and the right side were used for film formation of the dielectric layer. In each unit (50, 52), a ZTO (ZnSnO) target having Zn: Sn (atomic ratio) = 7: 3 and Zn: O (atomic ratio) = 1: 1 is set on the two opposing targets. Thus, a ZnSnO film can be formed. A box-type sputter unit 51 arranged in the middle was used for forming a thin film metal layer. A silver alloy target (Ag—Au) containing 1.35 at% neodymium (Nd) and 0.65 at% gold (Au) was set in the unit 51 so that a silver alloy film could be formed. As a sputtering power source, a pulsed DC power source (ENI type RPG-100) was used for forming a ZnSnO film, and a DC power source (ENI type DCG-100) was used for a silver alloy film.

  And as the transparent base film 60 as the transparent base material 16, it has the thickness shown in Table 2, the width is 50 cm, and the length is 100 m. Polyethylene terephthalate (PET) film (Toray Industries, Lumirror (registered trademark) ) U34 # 50 or # 100) roll 60a was used, and this roll 60a was set on the roll attachment shaft 34 arranged on the left side in FIG.

  Next, the film 60 is unwound from the film roll 60a, wound around the core (not shown) set on the roll attachment shaft 35 through the sputtering chamber 33, wound up to a predetermined length, and formed into a film roll 60b. 60 can be transported.

  Subsequently, while transferring the film 60 from the roll 60 a to the roll 60 b, the three box-type sputtering units 50, 51, 52 are operated, and the transparent base film 60 as the transparent base material 16 is shown in Table 2 below. The sputtering power and the conveyance speed at the time of film formation of the film 60 are adjusted so that the thickness is as shown, and the ZnSnO layer as the first layer, the silver alloy layer as the second layer, and the ZnSnO layer as the third layer are sequentially laminated. It was. The third layer was formed to half the thickness by the above process, and the remaining half thickness of ZnSnO was further laminated using the sputtering unit 52 in the subsequent unwinding process.

  Next, the three box-type sputter units 50, 51, 52 are operated while rewinding from the roll 60 b to the roll 60 a, and the sputtering power and the conveyance speed at the time of film formation of the film 60 are set so as to have the thicknesses shown in Table 2. Then, a ZnSnO layer as a third layer, a silver alloy layer as a fourth layer, and a ZnSnO layer as a fifth layer were further laminated. The fifth layer was formed to a half thickness by the above process, and ZnSnO having the remaining half thickness was laminated using the sputtering unit 52 in the subsequent rewinding process.

  Subsequently, while unwinding the film 60 from the roll a to the roll b, the three box-type sputtering units 50, 51, 52 are operated, and the sputtering power and the film 60 are formed so as to have the thicknesses shown in Table 2. The conveyance speed at the time was adjusted, and a ZnSnO layer as a fifth layer, a silver alloy layer as a sixth layer, and a ZnSnO layer as a seventh layer were further laminated.

  Through the above steps, a transparent heat reflective film having a 7-layer structure shown in Table 2 was obtained.

  Sputtering was performed under vacuum using argon (Ar) gas (purity: 99.999%) as a sputtering gas, and all layers were formed at a sputtering pressure of 0.30 Pa.

2. Production of laminated glass Using the transparent heat reflective film produced above, clear glass (thickness: 2 mm) as the first glass plate and the second glass plate, commercially available as the first intermediate layer and the second intermediate layer Polyvinyl butyral resin (thickness: 381 μm (15 mil)) was used. These were combined in the configuration of the first glass plate / first intermediate film / heat reflection film / second intermediate film / second glass plate, and pre-pressed at 110 ° C. in a vacuum bag. Then, the laminated glass was produced by carrying out this adhesion | attachment at 130 degreeC and 10 atmospheres (1.01325 MPa) for 1 hour with an autoclave. Dimensional change of base material by vitrification [Example 1-4]
In the production of the heat reflecting film, the alternating laminate 19 constituting the transparent heat reflecting film has a five-layer structure (the form shown in FIG. 3), and the film thicknesses of the metal layers and the dielectric layers are shown in Table 2. Except having changed into the thickness shown, it carried out similarly to the method of Example 1-1, and produced the heat | fever reflection film and the laminated glass.

[Example 1-5]
When producing the heat reflecting film, as the transparent substrate film 60, a polyethylene terephthalate (PET) film having a width of 100 cm and a length of 50 m (manufactured by Teijin DuPont Films Ltd., Teijin (registered trademark) Tetron (registered trademark) film) K) was used. In addition, the thickness of each metal layer and each dielectric layer was changed to the thickness shown in Table 2. Except these, it carried out similarly to the method of Example 1-4, and produced the heat | fever reflection film and the laminated glass.

[Example 1-6]
When producing the heat reflection film, a pure silver target is set in the box-type sputter unit 51 so that a silver film can be formed as a metal layer, and the film thicknesses of each metal layer and each dielectric layer are shown in Table 2. Changed to the indicated thickness. Except these, it carried out similarly to the method of Example 1-5, and produced the heat | fever reflection film and the laminated glass.

[Example 1-7]
When producing the heat reflecting film, a multilayer film having a thickness shown in Table 2, a width of 100 cm, and a length of 50 m was used as the transparent substrate film 60. The multilayer film is formed by extruding a polyethylene terephthalate-polyethylene naphthalate composite resin having a refractive index of 1.60 and a polyethylene naphthalate having a refractive index of 1.70 by a co-extrusion method and alternately laminating them by a multiplier. Was obtained. At this time, the total number of layers of the two resins was 300, and the respective film thicknesses were changed from 120 nm to 180 nm as the number of layers increased. The film thickness of the obtained multilayer film was 50 μm. The film had a reflection peak at 800 nm in a reflection spectrum measured in accordance with JIS R 3106-1985.

  Further, green glass (thickness: 2 mm) was used as the second glass plate.

  Except these, it carried out similarly to the method of Example 1-6, and produced the heat | fever reflection film and the laminated glass.

[Example 1-8]
A clear glass (thickness: 2 mm) having a size of 150 mm × 150 mm was fixed immediately below the FTS type box-type sputtering unit, and sputtering irradiation corresponding to the rates in Table 1 was performed. As a result, a heat reflecting plate was obtained in which alternating laminates (total number of laminates: 7 layers) composed of metal layers and dielectric layers having the configurations shown in Table 2 were directly formed on clear glass.

[Comparative Example 1]
In the production of the heat reflecting film, in the box-type sputtering unit (50, 52), a ZnO target was set on two opposing targets so that a ZnO film could be formed.

  Sputtering is performed under vacuum, using argon (Ar) gas (purity: 99.999%) as a sputtering gas and a sputtering pressure of 0.15 Pa. Further, each metal layer and each dielectric layer film The thickness was changed to the thickness shown in Table 2. Except these, the heat | fever reflective film and the laminated glass were produced by the method similar to Example 1-4.

[Comparative Example 2]
When producing a heat reflecting film, an AZO (Al—Zn—O: zinc aluminum oxide) target is set on two opposing targets in the box-type sputtering unit (50, 52) so that an AZO film can be formed. I made it. Further, sputtering is performed under vacuum, using Ar / O ₂ = 14/1 sccm as a sputtering gas and a sputtering pressure of 0.10 Pa. Further, the thickness of each metal layer and each dielectric layer is shown in Table 2. Changed to the indicated thickness. Except these, the heat | fever reflective film and the laminated glass were produced by the method similar to Example 1-4.

[Comparative Example 3]
When producing a heat reflecting film, an ITO (In-Sn-O: indium tin oxide) target is set on two opposing targets in the box-type sputter unit (50, 52) so that an AZO film can be formed. I made it. Further, sputtering is performed under vacuum, using Ar / O ₂ = 42/1 sccm as a sputtering gas, with a sputtering pressure of 0.30 Pa, and the film thicknesses of each metal layer and each dielectric layer are shown in Table 2. Changed to the indicated thickness. Except these, the heat | fever reflective film and the laminated glass were produced by the method similar to Example 1-4.

[Comparative Example 4]
As a transparent substrate film as the transparent substrate 16, a polyethylene terephthalate (PET) film having a thickness shown in Table 2 and having a width of 100 cm and a length of 50 cm (Lumirror (registered trademark) U34 #, manufactured by Toray Industries, Inc.) 50 or # 100) was used. On this film, a silver alloy (Ag—Pd) containing ZnSnO as a dielectric layer and 1 at% of Pd as a metal layer is formed using a magnetron sputtering method (apparatus name: roll coater W-50 manufactured by KOBELCO). A total of 5 layers were alternately laminated to form an alternately laminated body having the configuration shown in Table 2. Sputtering was performed under vacuum at a sputtering pressure of 1 Pa using argon (Ar) gas (purity: 99.999%) as a sputtering gas.

[Example 2-1]
In the sputtering apparatus used in Example 1-1, a ZTO (ZnSnO) target was set on one of the two opposing targets in the box-type sputtering units 50 and 52 used for forming the dielectric layer, and the other An AZO (ZnAlO) target was set. Here, a ZTO (ZnSnO) target having a Sn content of 30 wt% and Zn: O (atomic ratio) = 1: 1 was used as the ZTO target. As the AZO target, an AZO (ZnAlO) target having an Al content of 2% by weight and Zn: O (atomic ratio) = 1: 1 was used. A mixed film of ZnSnO and ZnAlO can be formed using these two targets in plasma. The composition of ZnSnO and ZnAlO in the mixed film correlates with the power ratio applied to each target. In this example, as shown in Table 1, by setting the ratio of the power applied to the ZTO target and the power applied to the AZO target to 7: 3, the composition of ZnSnO: ZnAlO = 7: 3 (weight ratio) was obtained. A mixed film was formed.

  A box-type sputter unit 51 arranged in the middle was used for forming a thin film metal layer. A silver alloy target (Ag—Au) containing 1.35 at% neodymium (Nd) and 0.65 at% gold (Au) was set in the unit 51 so that a silver alloy film could be formed. As a sputtering power source, a pulsed DC power source (ENI type RPG-100) is used for forming a ZnSnO-ZnAlO mixed film, and a DC power source (ENI type DCG-100) is used for a silver alloy film. It was.

Using the above sputtering apparatus, sputtering is performed under vacuum, sputtering gas is Ar / O ₂ = 44/1 sccm, sputtering pressure is 0.30 Pa, and sputtering power applied to each target is shown in Table 1. A heat reflecting film and a laminated glass were produced in the same manner as in Example 1-1 except that the values were changed to the values shown in FIG.

  The dimensional change of the PET film as a transparent substrate that occurred during laminated glass formation is 1% (1.01 times) in the MD direction (longitudinal direction), and 1% (1. 01 times).

[Example 2-2]
Other than changing the sputtering power applied to each target to the values shown in Table 1 and changing the thickness of each metal layer and each dielectric layer to the thickness shown in Table 2 when producing the heat reflecting film. Produced the heat | fever reflection film and the laminated glass like the method of Example 2-1.

[Example 2-3]
When producing the heat reflecting film, the alternating laminate 19 constituting the transparent heat reflecting film has a five-layer structure, and the sputtering power applied to each target is changed to the value shown in Table 1, and each metal layer and Except having changed the film thickness of each dielectric material layer into the thickness shown in Table 2, it carried out similarly to the method of Example 2-1, and produced the heat | fever reflection film and the laminated glass.

[Example 2-4]
When producing the heat reflecting film, as the transparent substrate film 60, a polyethylene terephthalate (PET) film having a width of 100 cm and a length of 50 m (manufactured by Teijin DuPont Films Ltd., Teijin (registered trademark) Tetron (registered trademark) film) K) was used. In addition, Example 2-3 except that the sputtering power applied to each target was changed to the values shown in Table 1 and the thicknesses of the metal layers and the dielectric layers were changed to the thicknesses shown in Table 2. In the same manner as described above, a heat reflecting film and a laminated glass were produced.

[Example 2-5]
When producing the heat reflecting film, a multilayer film having a thickness shown in Table 2, a width of 100 cm, and a length of 50 m was used as the transparent substrate film 60. The multilayer film is formed by extruding a polyethylene terephthalate-polyethylene naphthalate composite resin having a refractive index of 1.60 and a polyethylene naphthalate having a refractive index of 1.70 by a co-extrusion method and alternately laminating them by a multiplier. Was obtained. At this time, the total number of layers of the two resins was 300, and the respective film thicknesses were changed from 120 nm to 180 nm as the number of layers increased. The film thickness of the obtained multilayer film was 50 μm. The film had a reflection peak at 800 nm in a reflection spectrum measured in accordance with JIS R 3106-1985.

  Further, green glass (thickness: 2 mm) was used as the second glass plate.

  Except these, it carried out similarly to the method of Example 2-4, and produced the heat | fever reflection film and the laminated glass.

[Example 2-6]
A heat reflecting film was produced in the same manner as in Example 2-1.

  The obtained heat reflecting film was stretched in the MD direction (longitudinal direction) and the TD direction (lateral direction) using a stretching apparatus (small biaxial stretching machine manufactured by Shibayama Kagaku). The draw ratio was MD / TD = 1.01 times / 1.01 times (dimensional change: MD / TD = 1% / 1%).

  In addition, the sputter power and the conveyance speed at the time of film formation in each example and comparative example are as shown in the table below.

In the table, the second level and the third level in the first layer, the third layer, the fifth layer, and the seventh layer indicate the sputtering power (W) applied to the ZTO target and the AZO target.

[Evaluation]
1. Layer thickness measurement of alternating laminate and crystal structure analysis of dielectric layer (1) Film thickness measurement The thickness of each layer of the dielectric-metal alternating laminate film is obtained by taking a transmission electron microscope (TEM) image of the cross section of the film, Measured length. The measurement results are shown in Table 2. In addition, the thickness of each layer in Examples 2-2 to 2-5 is a converted film thickness based on the TEM measurement result in Example 2-1.

(2) Electron diffraction pattern The crystal structure analysis of the dielectric layer was performed using an electron diffraction image by TEM. 8A to 8F show TEM electron diffraction images of the dielectric film cross sections in the heat reflecting films obtained in Example 1-1, Comparative Examples 1 to 4, and Example 2-1.

  In the TEM electron beam diffraction pattern in Example 1-1 shown in FIG. 8A, a reflection peak is confirmed on the [311] plane. Also in the TEM electron diffraction pattern of the dielectric film cross section of the heat reflecting film obtained in Examples 1-2 to 1-8, a reflection peak was confirmed on the [311] plane as in FIG. 8A.

  Also, in the TEM electron diffraction pattern in Example 2-1 shown in FIG. 8F, a reflection peak was confirmed on the [311] plane. Further, as shown in FIG. 8F, in the TEM electron diffraction pattern in Example 2-1, in addition to the reflection peak of the [311] plane, the [101] plane, [002] plane, [100] of AZO The reflection peak of the surface was confirmed. Also in the TEM electron diffraction pattern of the dielectric film cross section of the heat reflecting film obtained in Examples 2-2 to 2-5, the same pattern as in FIG. 8F was confirmed.

  On the other hand, no reflection peak on the [311] plane was confirmed in the TEM electron diffraction patterns in Comparative Examples 1 to 4.

(3) Observation of TEM Image and Calculation of Occupation Ratio of Crystal Size and Crystal Region FIG. 6 shows a TEM cross-sectional image of the dielectric film in the alternating laminate in Example 1-1. FIG. 9 shows a TEM cross-sectional image of the dielectric film in the alternately laminated body in Example 2-1.

  As shown in FIGS. 6 and 9, it is confirmed that the dielectric film of this example has fine crystals dispersed in the ZnSnO amorphous phase. Also in the TEM cross-sectional images of the dielectric films of Examples 1-2 to 1-8 and Examples 2-1 to 2-5, microcrystals are dispersed in the amorphous phase of ZnSnO, as in FIGS. It had been.

  Furthermore, it is confirmed from FIG. 9 that the dielectric film in Example 2-1 has cracks in the thickness direction of the dielectric film. In addition, although illustration was abbreviate | omitted, the said crack had generate | occur | produced so that the alternate laminated body (dielectric layer and metal layer) might penetrate in the thickness direction. The said crack generate | occur | produces by the crimping | compression-bonding in the case of laminated glass. Moreover, also in the alternating laminated bodies in Examples 2-2 to 2-6, it was confirmed that cracks penetrating the alternating laminated bodies (dielectric layers and metal layers) in the thickness direction occurred as in FIG. It was done. In Example 2-6, a stretching process is performed after the film formation, and the crack is generated by the stretching process. The widths of cracks in the alternating laminates of Examples 2-1 to 2-6 were all less than 50 μm.

  The projected area equivalent circle diameter of the crystal region was calculated from the TEM image of the dielectric film cross section, and the occupancy ratio of the crystal region was calculated by binarizing the TEM cross section observation photograph.

  The results are shown in Table 2 and Table 3.

(4) Optical microscope observation The optical microscope photograph of the surface of the heat | fever reflective film in the laminated glass manufactured in Example 2-1 and the heat | fever reflective film after extending | stretching manufactured in Example 2-6 is shown in FIG. 10 and FIG. 18, respectively. . From FIG. 10 and FIG. 18, it is confirmed that a network-like crack is generated on the surface of the heat reflecting film (alternate laminated body). Furthermore, although illustration was abbreviate | omitted, also in Examples 2-2 to 2-5, it was confirmed that the mesh-shaped crack has arisen on the surface of a heat | fever reflection film.

2. Measurement of Electric Resistivity of Dielectric Layer With respect to the heat reflecting films obtained in Examples and Comparative Examples, the electric resistivity of the dielectric layer was measured by a four-probe method based on JISK 7194-1994.

3. Heat ray reflectivity / visible light transmittance The heat reflection film, laminated glass and heat reflection plate obtained in the examples and comparative examples were measured according to JIS R3106-1985, and the transmission spectrum and reflection spectrum of 300 to 2500 nm were measured. The light transmittance (Tvis) and solar radiation transmittance (Tts) were calculated. The transmission and reflection spectra were measured using U-4000 (manufactured by Hitachi, Ltd.) every 300 nm to 380 nm, every 10 nm for 380 to 780 nm, every 20 nm for 780 to 800 nm, and 800 to 2500 nm. For each, a transmittance of 0 ° and a reflectance of 5 ° were measured every 50 nm. The results are shown in Table 2 and Table 4.

4). Radio wave permeability Using the laminated glass or heat reflecting plate (size: 150 mm x 150 mm) obtained in the examples and comparative examples, the radio wave shielding rate (SE) was evaluated in the range of 100 MHz to 1000 MHz by the Advantest method. When the radio wave shielding property of 1000 MHz is 10 dB or less, it is evaluated as “◯”, 10-20 dB as “Δ”, and over 20 dB as “×”. The results are shown in Table 4.

5. Durability evaluation Using the laminated glass or heat reflecting plate (size: 150 mm × 150 mm) obtained in the examples and comparative examples, a heat resistance test of 100 ° C. × 100 hours was performed, and the haze (haze) before and after evaluation was determined. The measurement was made, and the haze change (ΔH) <1% was marked with ◯, and the ΔH ≧ 1% was marked with x. The results are shown in Table 4.

1) Details of the dielectric crystal structures A to F are as shown in Table 3.
2) In the dielectric films of Comparative Example 3 and Comparative Example 4, the reflection peak derived from the crystal phase does not exist in the electron diffraction pattern, and the crystal region in the present invention does not exist.

  From Table 2 to Table 4, the heat reflecting films and laminated glass of Examples 1-1 to 1-8 and Examples 2-1 to 2-6, in which the dielectric layer is composed of a crystalline region and an amorphous region of a metal oxide Further, it is confirmed that the heat reflecting plate has excellent visible light transmittance, heat ray reflectivity, radio wave transmittance and durability.

  In particular, it can be seen that Examples 1-1 to 1-8, in which the size of the crystal region is small, are particularly excellent in visible light transmittance.

  Moreover, it turns out that the radio wave permeability improves remarkably in Examples 2-1 to 2-6 having cracks.

  On the other hand, the heat reflection films and laminated glass of Comparative Examples 3 and 4 in which the dielectric layer was composed only of the amorphous region of the metal oxide had insufficient radio wave transmission. Further, the heat reflecting film and the laminated glass of Comparative Example 4 constituted only by the ZnSnO crystal phase also had poor durability.

  Further, the heat reflecting films of Comparative Examples 1 and 2 in which the dielectric layer was composed only of the ZnO or AZO crystal phase had insufficient visible light transmittance and low durability.

1 Laminated glass,
11 First glass plate,
12 first intermediate layer;
13 heat reflective film,
14 second intermediate layer,
15 second glass plate,
16 transparent substrate film,
16a, 16b dielectric film,
17 dielectric layer,
17a amorphous region,
17b crystal region,
18 metal layer,
19 alternating laminates,
20 heat reflector,
21 substrate,
22 adhesive layer,
23 crack,
30 vacuum chamber,
31, 32 roll chambers,
33 Sputtering chamber,
34, 35 Roll attachment shaft,
36 tension detector,
37 speed detector,
38 Freeroll,
40 gas supply system,
41 exhaust system,
50, 51, 52 Box-type sputtering unit,
60 films,
60a, 60b film roll,
100a, 100b target part,
110a ₁ , 110a ₂ , 110b ₁ , 110b ₂ target,
120 opposite space,
130a, 130b permanent magnet (magnetic field generating means),
132a, 132b, 182a, 182b fixing plate,
151 frame,
151a, 151b, 151e, 151f Side surfaces of the frame,
152d, 152e shielding plate,
180a, 180b permanent magnet (magnetic field adjusting means),
191a, 191b Pole plate,
193b opening,
201b leg of tubular electrode,
D Crack width.

Claims (20)

A substrate;
An alternating laminate in which metal layers and dielectric layers are alternately laminated, and both outermost layers are dielectric layers, located on the substrate;
The dielectric layer is a heat reflecting structure including a metal oxide crystal region and an amorphous region.   The heat reflecting structure according to claim 1, wherein the metal oxide includes tin-doped zinc oxide (ZnSnO).   The heat reflecting structure according to claim 1 or 2, wherein the crystal region has a diameter of 15 nm or less.   The heat | fever reflective structure of any one of Claims 1-3 in which the said dielectric material layer has a crack.   The heat reflecting structure according to claim 4, wherein the metal oxide includes tin-doped zinc oxide (ZnSnO) and at least one of aluminum-doped zinc oxide (ZnAlO) and zinc oxide (ZnO).   The heat | fever reflective structure body of any one of Claims 1-5 whose occupation ratio of the crystal region in the said dielectric material layer is 20-90 volume%. The heat | fever reflective structure body of any one of Claims 1-6 whose electrical resistivity of the said dielectric material layer is 1.0 * 10 ^<-2 > (omega ^| ohm) * cm or more.   The heat | fever reflective structure body of any one of Claims 1-7 whose number of the said metal layers which comprise the said alternating laminated body is 1-5.   The heat | fever reflective structure body of any one of Claims 1-8 whose single layer thickness of the said metal layer is 5-30 nm, and whose single layer thickness of the said dielectric material layer is 5-100 nm.   The heat reflecting structure according to claim 1, wherein the base material is a transparent resin film.   The heat reflecting structure according to claim 10, wherein the transparent resin film includes a polyester film or a polyolefin film.   The heat reflecting structure according to claim 10 or 11, wherein the transparent resin film is a multilayer film obtained by alternately laminating a plurality of layers having different refractive indexes.   The heat reflecting structure according to claim 1, wherein the base material is a glass plate. A dielectric layer made of a metal layer and a metal oxide is formed on a substrate by a sputtering unit that applies a magnetic field in a facing direction between a pair of targets that are arranged to face each other at a predetermined interval and restrains plasma in a facing space. Including alternately forming layers by alternately laminating the layers,
The method for manufacturing a heat reflecting structure, wherein the dielectric layer is formed by using a target containing ZnSnO and using a sputtering gas having an oxygen concentration of 1% or less under vacuum. In the film forming step, a target containing tin-doped zinc oxide (ZnSnO) and at least one of aluminum-doped zinc oxide (ZnAlO) and zinc oxide (ZnO) is used,
The manufacturing method according to claim 14, further comprising a step of generating cracks in the dielectric layer by extending the alternate laminated body in an in-plane direction after the film forming step.   A first glass plate, a first intermediate layer, the heat reflecting structure according to any one of claims 1 to 12, or the heat reflecting film produced by the production method according to claim 14 or 15. A laminated glass in which a second intermediate layer and a second glass plate are laminated in this order.   A transparent dielectric film comprising a metal oxide crystal region and an amorphous region, wherein the crystal region has a reflection peak on the [311] plane.   The transparent dielectric film according to claim 17, wherein the metal oxide includes tin-doped zinc oxide (ZnSnO).   The transparent dielectric film according to claim 18, which has a crack.   The transparent dielectric film according to claim 19, wherein the metal oxide includes tin-doped zinc oxide (ZnSnO) and at least one of aluminum-doped zinc oxide (ZnAlO) and zinc oxide (ZnO).