JP5527480B2 - Heat ray reflective radio wave transparent transparent laminate - Google Patents

Description

  The present invention relates to a heat ray reflective radio wave transmission transparent laminate, and relates to a heat ray reflection radio wave transmission transparent laminate suitable for automobile windshields, building window glass, and the like. More specifically, the sun's heat rays are reflected to prevent the temperature inside the vehicle or building from rising, but radio waves in the frequency band of mobile devices such as communication devices and televisions that arrive on the window glass of buildings, automobiles, etc. The present invention also relates to a heat ray reflective radio wave transmitting transparent laminate capable of efficiently transmitting visible light.

  2. Description of the Related Art Conventionally, a window glass in which a conductive thin film such as a metal is coated on a window glass or a film coated with a conductive thin film is pasted for the purpose of preventing solar heat rays. However, this conventional technique has a problem that transparency and transparency are insufficient due to hindering transmission of visible light. Further, in order to improve transparency and transparency, a glass or a film in which an oxide film, a metal film, and an oxide film are alternately laminated is invented (for example, see Patent Document 1). However, such a conventional technique has a problem that it becomes difficult to receive a radio wave by reflecting a radio wave in a frequency band of a communication device or a television broadcast, and recently, a radio wave of a mobile phone is obstructed and a call cannot be made. There was a point. On the other hand, in order to solve the problem that it is difficult to receive such radio waves, an invention has been made in which transparent dielectrics having different refractive indexes are laminated in layers, and the surface resistance value is controlled to make it easier to receive radio waves. (For example, refer to Patent Document 2). By adopting these configurations, the amount of attenuation of radio waves is reduced, and radio waves can be easily received. However, these techniques have a problem that the transmittance of visible light is reduced. Therefore, many techniques for multilayering transparent dielectrics having different refractive indexes have been invented in order to satisfy any of these heat ray shielding of the sun, transmission of visible light, and transmission of radio waves for communication or the like (see, for example, Patent Document 3). ). However, this conventional technique has a problem that the number of manufacturing steps is increased and costs are increased because different transparent dielectrics are formed into multiple layers by a vacuum film forming technique such as sputtering. In addition, a method of forming a granular metal layer by post-processing a uniform layer containing metal has been invented (see, for example, Patent Document 4). However, since this conventional technique also has post-processing, there is a problem that the manufacturing process is increased and costs are increased.

JP-A-4-357525 Japanese Patent Laid-Open No. 4-139037 JP-A-3-65531 JP 2002-328220 A

  The present invention has been made against the background of such prior art problems. That is, the object of the present invention is to prevent the increase in indoor temperature by solar heat ray shielding, save energy, maintain and improve transparency by transmitting visible light, and to transmit radio waves in the frequency band of communication devices, televisions, mobile phones, etc. An object of the present invention is to provide an excellent heat ray reflective radio wave transmitting transparent laminate.

As a result of intensive studies, the present inventors have found that the above problems can be solved by the following means, and have reached the present invention. That is, the present invention has the following configuration.
1. A heat ray reflective radio wave transmission transparent laminate in which a transparent dielectric layer B, a discontinuous metal layer C, and a transparent dielectric layer D are sequentially laminated on at least one surface of a substrate A, the transparent dielectric layer B and A layer E having a surface energy of 40 dyn / cm or less is laminated between the metal layers C, and a 1 GHz radio wave shielding effect is 10 dB or less.
2. The base material A is a transparent plastic film or glass, The heat ray reflective radio wave transmitting transparent laminate according to the first aspect described above.
3. The transparent plastic film is a polyester film or a polycarbonate film, The heat ray reflective radio wave transmitting transparent laminate according to the second aspect.
4). The heat ray reflective radio wave transmitting transparent laminate according to any one of the first to third aspects, wherein visible light transmittance at a wavelength of 550 nm is 70% or more and infrared transmittance at a wavelength of 1500 nm is 30% or less. .
5). The heat ray reflective radio wave transmitting transparent laminate according to any one of the first to fourth aspects, wherein the metal of the metal layer C is silver.

  According to the present invention, it is possible to provide a transparent laminate that has excellent heat ray reflectivity and transmits radio waves in a frequency band such as communication equipment, television broadcasting, and mobile phones.

1 is a schematic cross-sectional view of one embodiment of a heat ray reflective radio wave transmission transparent laminate of the present invention in which a transparent dielectric layer B, a metal layer C, and a transparent dielectric layer D are sequentially laminated on a substrate A. FIG. Other heat ray reflective radio wave transmission transparent laminates of the present invention in which a transparent dielectric layer B, a layer E having a surface energy of 40 dyn / cm or less, a metal layer C, and a transparent dielectric layer D are sequentially laminated on a substrate A It is a cross-sectional schematic diagram of one aspect. 1 is a schematic surface view of a heat ray reflective radio wave transmission transparent laminate of one embodiment of the present invention in which a transparent dielectric layer B, a metal layer C, and a transparent dielectric layer D are sequentially laminated on a substrate A. FIG.

  Hereinafter, the present invention will be described in detail.

(Heat ray reflective radio wave transmission transparent laminate)
The heat ray reflective radio wave transmission transparent laminate of the present invention is a laminate in which a transparent dielectric layer, a discontinuous metal layer, and a transparent dielectric layer are sequentially laminated on at least one surface of a substrate. For example, FIG. And has a structure as shown in FIG. The substrate is preferably transparent, and is a substrate for each layer that is sequentially laminated, and can give a certain rigidity to the laminate. Any transparent dielectric is provided to prevent reflection of visible light, increase the transmittance of visible light, and improve transparency. Therefore, a dielectric having a large refractive index is preferable. A metal layer is provided to reflect heat rays. If this metal layer has a continuous structure, it will reflect radio waves in the television and communication areas, resulting in poor radio wave transmission, which is one of the objects of the present invention. . Therefore, by discontinuous the metal layer, the conductivity of the metal layer is reduced (surface resistance is increased), and radio wave permeability is improved (radio wave shielding property is deteriorated). Here, the term “discontinuous” means that the metal layer has an island-like structure or a minute independent layer, and each metal layer is in a physically or electrically non-contact state. The shape of the independent metal layer is not particularly limited, but the thickness is preferably 5 to 30 nm, and the ten-point average roughness (Rz) is preferably 5 to 100 nm.

(Base material)
In order to satisfy the object of the present invention, the base material is preferably a transparent base material, considering the workability in the step of laminating each layer to the base material and the adhesion with each layer, and further preferred uses of the present invention, etc. A transparent plastic film or glass is preferred.

(Base material made of transparent plastic film)
In the present invention, the substrate A in the case of comprising a transparent plastic film is formed into a film by melt extrusion or solution extrusion of an organic polymer into a film, and stretched in the longitudinal direction and / or the width direction as necessary. It is preferable that the film has been subjected to heat setting and heat relaxation treatment. Examples of the organic polymer include polyethylene, polypropylene, polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polycarbonate, polyamide, polyimide, polyamideimide, polytetrafluoroethylene, and tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer. In particular, polyethylene terephthalate, polyethylene naphthalate, polycarbonate and the like are preferable.

  These organic polymers may be copolymerized with a small amount of other organic polymer monomers, or may be blended with other organic polymers.

  The thickness of the substrate made of the transparent plastic film used in the present invention is preferably 10 μm or more and 200 μm or less, more preferably 20 μm or more and 100 μm or less. When the thickness of the plastic film is less than 20 μm, it is not preferable because wrinkles are likely to occur when being bonded to glass, and handling in the metal or transparent dielectric layer forming process becomes difficult. On the other hand, if the thickness exceeds 200 μm, the visible light transmittance is reduced and the weight and thickness of the window are increased, which is not preferable.

  The substrate made of a transparent plastic film used in the present invention is a range that does not impair the purpose of the present invention, such as corona discharge treatment, glow discharge treatment, flame treatment, ultraviolet irradiation treatment, electron beam irradiation treatment, ozone treatment, etc. A surface activation treatment may be performed.

  In addition, the base material made of the transparent plastic film used in the present invention is a cured product mainly composed of a curable resin for the purpose of improving adhesion, imparting chemical resistance, and preventing precipitation of low molecular weight substances such as oligomers. A layer may be provided.

  The curable resin is not particularly limited as long as it is a resin that is cured by application of energy such as heating, ultraviolet irradiation, electron beam irradiation, etc., and silicone resin, acrylic resin, methacrylic resin, epoxy resin, melamine resin, polyester resin, urethane Resin etc. are mentioned. From the viewpoint of productivity, a curable resin containing an ultraviolet curable resin as a main component is preferable.

  Examples of such ultraviolet curable resins are synthesized from polyfunctional acrylate resins such as acrylic acid or methacrylic acid ester of polyhydric alcohol, diisocyanate, polyhydric alcohol and hydroxyalkyl ester of acrylic acid or methacrylic acid. Such polyfunctional urethane acrylate resins can be mentioned. If necessary, a monofunctional monomer such as vinyl pyrrolidone, methyl methacrylate, or styrene can be added to these polyfunctional resins for copolymerization.

  In order to improve the adhesion between the coating film and the cured product layer, it is effective to further treat the cured product layer. Specific methods include a discharge treatment method that irradiates glow discharge or corona discharge, a method of increasing carbonyl group, carboxyl group, hydroxyl group, a chemical treatment method of treating with acid or alkali, and an amino group. And a method of increasing polar groups such as a hydroxyl group and a carbonyl group.

  The ultraviolet curable resin is usually used by adding a photopolymerization initiator. As the photopolymerization initiator, known compounds that absorb ultraviolet rays and generate radicals can be used without any particular limitation. Examples of such photopolymerization initiators include various benzoins, phenyl ketones, and benzophenones. And the like. The addition amount of the photopolymerization initiator is preferably 1 to 5 parts by mass with respect to 100 parts by mass of the ultraviolet curable resin.

  The concentration of the resin component in the coating solution can be appropriately selected in consideration of the viscosity according to the coating method. For example, the proportion of the total amount of the ultraviolet curable resin and the photopolymerization initiator in the coating solution is usually 20 to 80% by mass. Moreover, you may add other well-known additives, for example, leveling agents, such as a silicone type surfactant and a fluorine type surfactant, to this coating liquid as needed.

(Base material made of glass)
When the substrate A is made of glass, the glass includes float plate glass, mold plate glass, ground plate glass, netted glass, tempered plate glass, laminated glass, multi-layer glass, etc. depending on the production method and structure, and borosilicate glass and soda depending on the components. Examples include lime glass, quartz glass, lead glass, silica glass, and alkali-free glass. Among them, for the purposes of the present invention, it is highly transparent, resistant to thermal shock, and has a low coefficient of thermal expansion, so it is structurally tempered glass, flow and plate glass, componentally borosilicate glass, soda lime glass, etc. Is preferred. Further, the glass surface may be subjected to surface treatment such as plasma treatment, fluorine treatment, etching treatment, wet coating and the like within a range not impairing transparency and strength.

(Transparent dielectric layer)
The material of the transparent dielectric layers B and D may be any metal oxide, metal nitride, metal oxynitride or the like which is a transparent dielectric, but Zn, Al, Ti, Sn, Zr, Ta as metal components , Oxides of at least one element selected from the group consisting of W, Bi, Nb and Hf, nitrides of at least one element selected from the group consisting of Si and Al, Sn, Al, Si, Ti, Zr An oxynitride of at least one element selected from the group consisting of Hf and Hf is preferable. In particular, in order to improve transparency, an oxide made of Ta or Sn, which is a transparent dielectric having a high refractive index, is preferable.

  The two transparent dielectric layers B and D may be transparent dielectrics composed of the same components or compositions, or may be transparent dielectrics composed of different components or compositions.

  The thickness of the transparent dielectric layer is preferably 10 nm or more and 100 nm or less, and particularly preferably 20 nm or more and 80 nm or less. When the thickness of the transparent dielectric layer is less than 10 nm, the antireflection property of visible light becomes insufficient, and when it exceeds 100 nm, the transmittance of visible light is deteriorated.

(Discontinuous metal layer)
In the present invention, the metal used for the discontinuous metal layer is preferably a layer composed of a metal such as silver, palladium, gold, platinum, Ni, Al or an alloy thereof. In particular, a layer made of silver or a metal containing silver as a main component is preferable because infrared reflection performance is high and visible light is not absorbed.

  Furthermore, it is preferable to include a metal element such as Pd, Pt, Au, or Cu as another metal element because a layer having excellent chemical durability and migration resistance can be formed. However, if the added amount is too large, the visible light transmittance is lowered, so that it is suitably 5.0 at% or less, and particularly preferably 0.5 at% or more and 2.0 at% or less.

  The thickness of the discontinuous metal layer is preferably 5 nm or more and 30 nm or less. In particular, 7 nm or more and 20 nm or less are preferable. When the thickness of the discontinuous metal layer is less than 5 nm, the heat ray reflection becomes insufficient, and when it exceeds 30 nm, the visible light transmittance is deteriorated.

  As a method of adjusting the thickness of the discontinuous metal layer, the sputtering method can be adjusted by adjusting the pressure in the chamber, the discharge current, and the discharge time. In the case of the vacuum deposition method, the pressure in the chamber, the heating temperature, and the time can be adjusted. It is possible by adjusting. Further, in the case of a wet coating method, it is possible to adjust the coating solution concentration and the dry coating thickness.

  The ten-point average roughness (Rz) of the discontinuous metal layer is preferably 5 nm or more and 100 nm or less. 10 nm or more and 70 nm or less are particularly preferable. When the Rz of the discontinuous metal layer is less than 5 nm, the radio wave transmission of Tsu TV and communication band is deteriorated, and when it exceeds 100 nm, the visible light transmittance is deteriorated.

  As a method of adjusting Rz, a method of adjusting the thickness, a method of adjusting the surface energy of the base layer on which the metal layer is laminated, and a metal layer placed on the base layer when sputtering or vacuum deposition is used. There are a method of adjusting the hole diameter of the mask or mesh, a method of adjusting the shape and size of the discontinuous metal layer by etching or patterning after the continuous metal layer is formed.

  Moreover, it is preferable that the average diameter of an island-like discontinuous metal layer is 5 micrometers-10 mm. When the average diameter of the discontinuous metal layer is outside these ranges, it is difficult to transmit radio waves in the GHz band, and it is difficult to transmit radio waves in the television and communication bands.

  That is, by making the metal layer discontinuous, the conductivity of the metal layer is reduced (surface resistance is increased), and radio wave permeability is improved (radio wave shielding property is deteriorated). Here, the term “discontinuous” means that the metal layer has an island-like structure or a minute independent layer, and each metal layer is in a physically or electrically non-contact state. The shape of the independent metal layer is not particularly limited, but a gap between discontinuous metal layers is narrow (the area of the portion without the metal layer is small) and is in a physically or electrically non-contact state. Although a shape close to a circle may be used, a shape in which a discontinuous metal layer can be present in a close-packed shape is particularly preferable, even if it is a triangle, a quadrangle, a hexagon, or an indefinite shape.

  As for the size, in order to facilitate transmission of radio waves in the television or communication band, the average diameter of each metal island is preferably 5 to 100 μm, or 1 to 10 mm, because of its wavelength. Moreover, it is preferable that thickness is 5-30 nm. If the average diameter of each metal island exceeds 10 mm, it is difficult to transmit radio waves in a television or communication band, which is not preferable.

(Other layers)
In addition to these layers, a layer having a surface energy of 40 dyn / cm or less is preferably provided between the transparent dielectric layer B and the metal layer C in order to form a discontinuous metal layer. Fluorine compounds and silicon compounds are preferred, especially polytetrafluoroethylene (surface energy: 18 dyn / cm = 18 mN / m (= 18 mJ / m ² )), tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer, siloxane, silicone, and the like. preferable. The thickness of the layer having a surface energy of 40 dyn / cm or less is preferably 5 nm or more and 40 nm or less, and particularly preferably 8 nm or more and 30 nm or less. When the thickness is less than 5 nm, the metal layer is unlikely to be discontinuous, and when it exceeds 40 nm, the transmittance of visible light is deteriorated. When a layer having a surface energy of 40 dyn / cm or less is provided, the metal cohesive force is increased when the metal layer is formed by a sputtering method or the like, and as a result, the metal layer is likely to be island-shaped or uneven. The surface energy data is shown at 20 ° C.

  Further, in order to improve the chemical durability of the discontinuous metal layer, a layer made of a metal having high chemical stability, for example, a metal such as Ta, Ti, Pt, or Au, is provided on the discontinuous metal layer. It is also preferable. The thickness of this layer is preferably 1 nm or more and 5 nm or less. In particular, 1 nm or more and 3 nm or less are preferable. If it is less than 1 nm, it is insufficient to improve the chemical durability of the discontinuous metal layer, and if it exceeds 5 nm, the transparency of visible light or radio waves in the communication area is impaired.

  In the present invention, as a method for forming a transparent dielectric, a discontinuous metal layer, and other layers on a substrate made of a transparent plastic film or glass, a sputtering method, a vacuum deposition method, a CVD method, an ion plating method can be used. A dry film-forming method such as a coating method, a coating method (such as a bar coating method, a gravure coating method, or a reverse coating method) or a wet film-forming method such as plating can be used. Since it is easy to form a uniform thin film, a dry film forming method is preferable, and a sputtering method is particularly preferable.

  In order to form a discontinuous metal layer, it is also preferable to form a film by a dry film formation method with a mask, a mesh, or the like placed on the dielectric layer. It is also preferable to form a discontinuous metal layer by etching or patterning after forming a uniform metal layer.

  When a discontinuous metal layer is formed by a mask, the size of each metal island can be adjusted by the mask diameter and the distance between masks. Therefore, the mask diameter is preferably 0.5 to 7.0 mm.

In order for the heat ray reflective radio wave transmission transparent laminate of the present invention to satisfy the target properties of heat ray reflectivity, transparency, and radio wave shielding, specifically, the infrared ray transmittance at a wavelength of 1500 nm is 30% or less. In addition, the visible light transmittance at a wavelength of 550 nm is preferably 70% or more, and the radio wave shielding effect at 1 GHz is preferably 10 dB or less. Here, the infrared transmittance was measured at a wavelength of 1500 nm where a difference in transmittance in the infrared region was noticeable, and the visible light transmittance was measured at a wavelength of 550 nm where the difference in transmittance in the visible light region was noticeable. . In addition, the radio wave shielding effect (radio wave transmittance) was measured at a frequency of 1 GHz within the range because the frequency range of the radio wave of the mobile phone was approximately 800 to 1200 MHz .

  In order to reduce the infrared transmittance at a wavelength of 1500 nm to 30% or less, the visible light transmittance at a wavelength of 550 nm to 70% or more, and the radio wave shielding effect at 1 GHz to 10 dB or less, on at least one surface of the substrate, It is preferable that a transparent dielectric layer, a discontinuous metal layer, and a transparent dielectric layer are sequentially laminated. The thickness of the discontinuous metal layer is 5 nm or more and 30 nm or less, and the ten-point average roughness (Rz) is 5 nm. As mentioned above, it is preferable that it is 100 nm or less.

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the examples. In addition, the following Examples 8-10 shall be read as Reference Examples 8-10. Moreover, the performance of the heat ray reflective radio wave transmission transparent laminate was measured by the following method.

(1) Film thickness measurement (transparent dielectric layer, metal layer, other layers)
After embedding in 1 mm × 10 mm in cut epoxy resin for electron microscopy Samples were fixed to the article holder ultramicrotome to prepare a cross-section parallel thin slice the short side of the embedded sample pieces. Next, observation was performed using a transmission electron microscope (manufactured by JEOL Ltd., JEM2010) at a site where the sliced thin film was not significantly damaged. After observing the acceleration voltage at 200 kV and 20000 times, the film thickness of each layer was measured at 100 points, and the average was taken as the film thickness.

(2) Ten-point average roughness (Rz) (metal layer)
Using an atomic force microscope E-Sweep (manufactured by SII-NT), observe the morphology of the metal layer surface (DFM mode, 20 μm scanner, observation field of view: 10 × 10 μm 2), and determine the ten-point average roughness (Rz). It was measured.

(3) Visible light transmittance Visible light transmittance at a wavelength of 550 nm was measured using an ultraviolet-visible light spectrophotometer U-3500 manufactured by Hitachi, Ltd.

(4) Infrared transmittance The infrared transmittance at a wavelength of 1500 nm was measured using an ultraviolet-visible light spectrophotometer U-3500 manufactured by Hitachi, Ltd.

(5) Radio wave shielding performance (attenuation effect)
Heat-reflective radio wave transparent film or glass cut into a 5cm x 5cm square was affixed to a sample fixture made of aluminum with conductive tape, and an electric field was applied using a radio shield characteristic tester MA8602C manufactured by "Anritsu" ( KEC method). The radio wave shielding performance at 1 GHz was measured using “Anritsu” spectrum analyzer MS2661C.

(6) Average diameter of discontinuous metal layer A sample cut into 5 cm x 5 cm is observed with a differential interference microscope, 10 discontinuous metal layers are selected at random, and the major axis and minor axis of each island are measured. The average diameter was calculated. The major axis is the diameter of the circumscribed circle of the island, and the minor axis is the diameter of the inscribed circle of the island.

[Example 1]
A biaxially oriented transparent PET film (Toyobo Co., Ltd., A4300, thickness 50 μm, Tg 67 ° C.) having an easy-adhesion layer on both sides is cut into 5 × 5 cm and installed in a high-frequency sputtering apparatus SPC-350UHV manufactured by “Canon Anelpa” First, Ta was used as a target. The pressure in the chamber was evacuated to 2.0 × 10 ⁻³ Pa or less, Ar was introduced at 10 sccm, O ₂ was introduced at 5 sccm, and the total flow rate was 15 sccm. Thereafter, the pressure in the chamber was adjusted to 0.4 Pa, and the discharge current was set to 0.3 A using a direct current sputtering method. At this time, the substrate (PET film) temperature was room temperature. Thus it was formed a _Ta 2 _{O 5} on the substrate.

Next, the target was replaced with a PTFE (polytetrafluoroethylene, surface energy 18 dyn / cm) sheet (Fullon made by Asahi Glass), the pressure in the chamber was exhausted to 2.0 × 10 ⁻³ Pa or less, and Ar was 25 sccm as a discharge gas. Introduced. Thereafter, the pressure in the chamber was adjusted to 0.3 Pa, and the input power was set to 30 W using a high frequency sputtering method. At this time, the substrate (PET film) temperature was room temperature. Thereby, a PTFE layer was formed on the Ta ₂ O ₅ layer.

Next, the target was replaced with Ag, the pressure in the chamber was evacuated to 2.0 × 10 ⁻³ Pa or less, and 25 sccm of Ar was introduced as a discharge gas. Thereafter, the pressure in the chamber was adjusted to 0.4 Pa, and the discharge current was set to 0.2 A using a direct current sputtering method. At this time, the substrate (PET film) temperature was set to 180 ° C. Thereby, an Ag layer was formed on the PTFE layer.

Next, the target was changed to Ta, the pressure in the chamber was evacuated to 2.0 × 10 ⁻³ Pa or less, and 25 sccm of Ar was introduced as a discharge gas. Thereafter, the pressure in the chamber was adjusted to 0.4 Pa, and the discharge current was set to 0.3 A using a direct current sputtering method. At this time, the substrate (PET film) temperature was room temperature. Thereby, a Ta layer was formed on the Ag layer.

  Next, the target remains Ta and the pressure in the chamber is 2.0 × 10^-3Exhaust to Pa or less, Ar 10 sccm, O₂5 sccm was introduced, and the total flow rate was 15 sccm. Thereafter, the pressure in the chamber was adjusted to 0.4 Pa, and the discharge current was set to 0.3 A using a direct current sputtering method. At this time, the substrate (PET film) temperature was room temperature. As a result, Ta layer is formed on the Ta layer.₂O ₅Was deposited. This produced the heat ray reflective radio wave transmission transparent film. Microscopic observation confirmed that the Ag layer was discontinuous.

[Example 2]
Heat-reflecting radio wave transmitting transparent glass in the same manner as in Example 1 except that the base material is changed to a borosilicate glass having a thickness of 0.5 mm and a length and width of 5 cm × 5 cm, and the base material temperature during direct current sputtering of Ag is 240 ° C. Was made.

Example 3
A heat ray reflective radio wave transparent film was produced in the same manner as in Example 1 except that the Ta layer was not formed.

Example 4
A heat ray-reflecting radio wave transmitting transparent glass was produced in the same manner as in Example 2 except that the discharge current during the Ag film formation was 0.1 A.

Example 5
A heat ray-reflecting radio wave transmitting transparent glass was produced in the same manner as in Example 2 except that the discharge current during the Ag film formation was 0.4 A.

Example 6
A heat ray reflective radio wave transparent film was produced in the same manner as in Example 1 except that the base material was changed to polycarbonate (PC) and the base material temperature during direct current sputtering of Ag was 210 ° C.

Example 7
Reflection of heat rays in the same manner as in Example 1 except that the Ta target used for forming the Ta ₂ O ₅ layer was changed to zinc (Zn) and the discharge current using the direct current sputtering method was set to 0.4 A. A radio wave transparent film was produced.

Example 8
When PTFE is used as a target, a layer having a surface energy of 40 dyn / cm or less is not formed, and when a film is formed by a direct current sputtering method using Ag as a target, the thickness is 0.1 mm on the substrate. A heat ray reflective radio wave transparent film was produced in the same manner as in Example 1 except that a 5 mm stainless steel mask was installed. Microscopic observation confirmed that the Ag layer was discontinuous.

Example 9
A heat ray-reflecting radio wave transmitting transparent glass was prepared in the same manner as in Example 8 except that a borosilicate glass was used as a substrate and a stainless steel mask having a diameter of 1.5 mm was installed to form an Ag layer. Microscopic observation confirmed that the Ag layer was discontinuous.

Example 10
A heat ray-reflecting radio wave transmitting transparent glass was produced in the same manner as in Example 9 except that a stainless steel mask having a diameter of 2.0 mm was installed to form an Ag layer. Microscopic observation confirmed that the Ag layer was discontinuous.

Example 11
A heat ray reflective radio wave transparent film was produced in the same manner as in Example 1 except that Ni was used for the metal layer.

Example 12
A heat ray reflective radio wave transmitting transparent glass was produced in the same manner as in Example 2 except that the layer provided before the metal layer was laminated was changed from PTFE to hexamethyldisiloxane (surface energy 31.0 dyn / cm).

[Comparative Example 1]
A laminated film was produced in the same manner as in Example 1 except that the substrate temperature was set to room temperature when forming a film by direct current sputtering using Ag as a target.

[Comparative Example 2]
A laminated film was produced in the same manner as in Example 1 except that a layer having a surface energy of 40 dyn / cm or less was not formed and a target was formed by direct current sputtering using Ag as a target.

[Comparative Example 3]
Similar to Example 1 except that borosilicate glass is used as the base material, Ag is used as the target, and the base material temperature is 240 ° C. and the discharge current is 1.0 A when the direct current sputtering method is used. Thus, a laminated glass was produced.

[Comparative Example 4]
A laminated film was produced in the same manner as in Example 1 except that the transparent dielectric layer was not formed.

[Comparative Example 5]
A laminated film was produced in the same manner as in Example 1 except that a discontinuous metal layer was not formed.

[Comparative Example 6]
When PTFE is used as a target, a layer having a surface energy of 40 dyn / cm or less is not formed, and further, when a film is formed by direct current sputtering using Ag as a target, a thickness of 0. A laminated film was produced in the same manner as in Example 1 except that a 4 mm stainless steel mask (mesh) was installed.

[Comparative Example 7]
A laminated film was produced in the same manner as in Example 1 except that the transparent dielectric layer was formed on the substrate and not formed on the discontinuous metal layer. That is, the Ta layer was provided on a layer having a surface energy of 40 dyn / cm or less.

[Comparative Example 8]
A laminated glass was produced in the same manner as in Example 9 except that the transparent dielectric layer was not formed.

[Comparative Example 9]
A laminated film was produced in the same manner as in Example 1 except that neither the transparent dielectric layer nor the layer having a surface energy of 40 dyn / cm or less was formed, and the Ag layer was formed using a direct current sputtering method.

  From Table 1, the heat ray reflective radio wave transmission transparent laminates of Examples 1 to 12 satisfying the scope of the present invention form a transparent dielectric layer and a discontinuous metal layer, and heat ray reflectivity, visible light transmittance, and It was confirmed that the radio wave transmission of TV and communication band is excellent. On the other hand, in Comparative Example 1 in which the substrate temperature is set to room temperature, the cohesive force does not work when the metal adheres to the substrate by sputtering, and the uniformly attached state is maintained. The radio wave permeability of the band was insufficient. Particularly in Comparative Example 2 where no effort was made to make the metal layer discontinuous, the radio wave transmission was insufficient. In Comparative Example 3 in which the thickness of the metal layer was large, the radio wave transmission was not always sufficient, and the visible light transmission was not sufficient. In Comparative Example 4 having no transparent dielectric layer, the visible light transmittance was insufficient. Further, Comparative Example 5 having no metal layer has insufficient heat ray reflectivity, and Comparative Example 6 having an extremely fine mask diameter at the time of Ag film formation cannot make the metal layer sufficiently discontinuous. In addition to being insufficient, heat ray reflectivity was also insufficient. Further, Comparative Example 7 having only one transparent dielectric layer and Comparative Example 8 having no transparent dielectric layer had insufficient transparency. Further, in Comparative Example 9 in which only the metal layer was formed, the metal layer was not discontinuous and the radio wave permeability was deteriorated.

  The heat ray-reflecting radio wave transmission transparent laminate of the present invention has excellent heat ray reflectivity, so that the temperature rise in the room due to sunlight in the summer is reduced, and the heat in the room in the winter is difficult to escape to the outside. There is an effect to. Moreover, since it is excellent in transparency, it is safe without disturbing the field of view when driving a car, and the outdoor scenery and situation can be comfortably viewed. Further, since radio waves from a television, a communication band, a mobile phone, and the like are transmitted, it is possible to prevent the occurrence of a television ghost and the radio disturbance of a communication device and a mobile phone. For these reasons, the heat ray reflective radio wave transmitting transparent laminate of the present invention is expected to greatly contribute to daily life and industry.

1: Heat ray reflective radio wave transmission transparent laminate 2: Substrate A made of transparent plastic film or glass
3: Transparent dielectric layer B
4: Discontinuous metal layer C
5: Transparent dielectric layer D
6: Layer E having a surface energy of 40 dyn / cm or less

Claims (5)

A heat ray reflective radio wave transmission transparent laminate in which a transparent dielectric layer B, a discontinuous metal layer C, and a transparent dielectric layer D are sequentially laminated on at least one surface of a substrate A, the transparent dielectric layer B and A layer E having a surface energy of 40 dyn / cm or less is laminated between the metal layers C, and a 1 GHz radio wave shielding effect is 10 dB or less. Heat reflecting radio wave transmission transparent laminate according to claim 1, base material A, characterized in that a transparent plastic film or glass. The heat-reflecting radio wave transmission transparent laminate according to claim 2 , wherein the transparent plastic film is a polyester film or a polycarbonate film. And the visible light transmittance at a wavelength of 550nm is 70% or more, heat-reflecting radio wave transmission transparent laminate according to any one of claims 1 to 3, the infrared transmittance at a wavelength of 1500nm is equal to or less than 30%. The heat ray reflective radio wave transmitting transparent laminate according to any one of claims 1 to 4 , wherein the metal of the metal layer C is silver.