JP2010064295A - Window glass - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat ray-reflecting window glass capable of being easily and inexcesively produced and showing superior heat ray reflection. <P>SOLUTION: The window glass has a metal-laminated base plate on one surface of the glass. The metal-laminated base plate has a random mesh-like metal layer on the transparent base plate. The mesh of the metal layer has an average line width of 0.01 to 2 μm and an average opening diameter of 0.5 to 10 μm. The metal-laminated base plate on the transparent base plate side is piled up on the glass. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention provides a heat ray reflective substrate suitable for an energy-saving window material that can be produced at low cost by making solar radiation incident from outside, suppressing heat radiation from the inside to the outside, and reducing the heating load. It relates to window glass.

  In recent years, it has become increasingly important to reduce the heating and cooling load from the viewpoint of energy saving, and window glass having heat insulation properties and heat ray reflectivity is being adopted as energy saving window materials. As a typical energy-saving window material, two or more single glass plates are combined at regular intervals, the periphery is sealed with a metal frame or an adhesive, etc., and multi-layer glass in which dry air is enclosed is common. There is a Low-E multi-layer glass in which the heat insulating performance is further improved by providing a metal thin film called a Low-E film on one surface of the single glass constituting the multi-layer glass. Also, heat ray reflective glass in which a metal thin film layer of metal or metal oxide is formed on a single plate glass, and heat ray reflective glass in which a thin metal substrate having heat ray reflectivity formed on a single plate glass by a vacuum deposition method or a sputtering method is attached. Etc.

Low-E film of Low-E multi-layer glass is a metal thin film made by thinning metal by sputtering method or vacuum evaporation method, so it requires high vacuum and is not suitable for large area. There are drawbacks. In addition, the heat ray reflective glass in which the metal thin film layer is formed on the single plate glass also has a problem of high cost as described above because the sputtering method is mainly used for forming the metal thin film layer.
A heat ray reflective glass in which a heat ray reflective film in which a metal thin film of metal or metal oxide is laminated is attached to a single plate glass is also a known technique, but a sputtering method or a vacuum evaporation method is used for forming a metal thin film. Therefore, in addition to the above-mentioned problems, it is difficult to obtain a film that achieves both visible light transmittance and heat ray blocking properties with respect to the metal vapor-deposited film. There is also a problem that only a thin film is obtained.

An object of the present invention is to provide a window provided with a heat ray reflective substrate that can be manufactured by a simple method without using an expensive physical film formation method, and that is inexpensive, highly productive, and heat ray reflective. To provide glass.

The heat ray reflective window glass of the present invention is as follows.
1) A window glass having a metal laminated substrate on one side of the glass,
The metal laminate substrate is a metal laminate substrate having a random network metal layer on a transparent substrate,
The metal layer has a mesh shape with an average line width of 0.01 μm to 2 μm and an average opening diameter of 0.5 μm to 10 μm.
A window glass, wherein a transparent substrate side of a metal laminated substrate is laminated with glass.
2) The window glass according to 1) above, having a surface specific resistance of 10 ⁶ Ω / □ or less.
3) The window glass according to 1) or 2) above, wherein the average reflectance of heat rays at a wavelength of 3 to 30 μm is 30% or more.
4) A random mesh-like metal layer is formed on a transparent substrate by applying a coating liquid containing a metal component on the transparent substrate, according to any one of 1) to 3) above. Window glass.
5) The coating liquid is an emulsion having a continuous phase and a discontinuous phase, the continuous phase contains at least one metal component, and the discontinuous phase is a droplet having an average droplet diameter of 0.1 to 5 μm. The window glass according to any one of 1) to 4) above, wherein
6) The window glass according to any one of 1) to 5), wherein the metal laminated substrate has a protective layer on the metal layer.
6) The window glass according to any one of 1) to 6), wherein the transparent substrate is a thermoplastic resin film.

  According to the present invention, as described below, a heat ray reflective window glass that can be produced by a simple method without using an expensive physical film formation method, can be produced at low cost, and has excellent heat ray reflectivity is provided. There is to do.

  The window glass of the present invention is a window glass having a metal laminated substrate on one side of the glass, the metal laminated substrate is a metal laminated substrate having a random mesh-like metal layer on a transparent substrate, and the metal layer is The window glass is characterized in that it has a mesh shape with an average line width of 0.01 μm to 2 μm and an average opening diameter of 0.1 μm to 10 μm, and the transparent substrate side of the metal laminated substrate is laminated with glass.

  First, the metal laminated substrate used for the window glass of the present invention will be described. The metal laminated substrate used for the window glass has a random mesh-like metal layer on a transparent substrate, and the metal layer has a mesh shape with an average line width of 0.01 μm to 2 μm and an average opening diameter of 0.5 μm to 10 μm. It is a feature.

  It is important that the average opening diameter of the metal layer of the metal laminated substrate according to the present invention is in the range of 0.5 to 10 μm, preferably in the range of 0.5 to 5 μm, more preferably 0.5 to 1 μm. Range. When the average aperture diameter is less than 0.1 μm, the visible light transmittance is low. Therefore, when a metal laminated substrate having such an average aperture diameter is used as part of the window glass, the visible light transmittance of the window glass is also reduced. Therefore, when the average aperture diameter exceeds 10 μm, the reflection efficiency for the heat rays to be blocked decreases, so that when the metal laminated substrate having such an average aperture diameter is used as a part of the window glass, Since it is not preferable in terms of reflectivity, it is important that the average opening diameter of the metal layer is in the range of 0.1 to 10 μm.

Here, the average opening diameter of the metal layer was calculated by the following method. First, the surface of the sample was observed at a magnification of 500 using a digital microscope (VHX-200, manufactured by Keyence Corporation), and photographic data was stored. Next, the stored photographic data was selected and displayed on the screen, and brightness extraction was performed with a measurement tool built in the apparatus, and the line part was binarized to black and the opening part to white. In that case, it was set as the luminance range 195-255. Next, a white spot (noise) having an area of 400 pixels or less existing in the black part (line part) is removed by the “small grain removal” process, and an area of 400 pixels existing in the white part (opening part) by the “fill hole” process The following black spots (noise) were removed. Thereafter, an opening that was cut off by the frame of the screen and was not entirely displayed was converted into a black portion by “deletion” processing. Subsequently, the total area and perimeter were obtained by the “batch calculation” process. Thereafter, the average area was calculated from the total area / number of openings, and the average opening diameter was calculated from the following formulas (1) and (2).
Average area = π × r ² Formula (1)
Average opening diameter = 2r Formula (2)
It is important that the average line width of the metal layer of the metal laminated substrate according to the present invention is 0.01 μm to 2 μm, preferably in the range of 0.1 to 1 μm, more preferably 0.1 to 0.5 μm. Range. When the average line width of the metal layer is less than 0.01 μm, conductivity cannot be obtained in the metal laminated substrate. Therefore, using the metal laminated substrate having such an average line width as a part of the window glass is a heat ray. In terms of reflectivity, it is not preferable as a window glass, and when the average line width of the metal layer exceeds 2 μm, the visible light transmittance of the metal multilayer substrate becomes low. Since it is not preferable as a window glass to be used as a part of the window glass, it is important that the average line width of the metal layer of the metal laminated substrate is 0.01 μm to 2 μm.

  Here, the average line width of the metal layer was measured using a digital microscope (manufactured by Keyence Corporation, VHX-200) as described later.

  The total light transmittance of the metal laminated substrate according to the present invention is preferably 50% or more, more preferably 60% or more, still more preferably 70% or more, and particularly preferably 80% or more. When the total light transmittance is less than 50%, there may be a problem in terms of transparency when the window glass is provided with such a metal laminated substrate. In addition, although the total light transmittance of a metal laminated substrate is so preferable that it is high, since it is thought to be practically difficult to make it higher than 90%, an upper limit is considered to be about 90%.

  It is important that the metal layer of the metal laminated substrate used for the window glass of the present invention is formed in a random network shape on the transparent substrate. By making the metal layer into a random network, the window glass provided with the metal laminated substrate having the metal layer exhibits a good reflection characteristic with respect to heat rays while maintaining transparency. It is important to be a layer. In the case of a metal layer having no random mesh openings, the transparency is inferior and unfavorable because of a problem in visibility, and when it becomes a regular mesh opening, the reflection characteristics with respect to heat rays may be inferior. Since it is considered, it is not preferable.

“Random mesh” is a shape having a linear portion and an opening surrounded by the linear portion, and one or both of the linear portion and the opening do not have a certain shape. Say.
Preferably, it has a linear portion that does not have a certain shape and an opening portion that is surrounded by the linear portion and does not have a certain shape, and a plurality of the opening portions are connected. Since the shape of the linear portion is usually grasped by its width and thickness, in the present invention, “the linear portion does not have a constant shape” means that the width and thickness are not constant (single It may be understood that the form does not have a width or thickness. In the present invention, since the metal layer has the above shape, the linear part is composed of a component containing metal, and the opening is open, the linear part exhibits conductivity, and the opening has transparency. Bear. Therefore, the total light transmittance can be controlled by the area occupied by the linear portion (or the area occupied by the opening).

  The formation method of the random mesh-like metal layer on the transparent substrate in the metal laminated substrate is not particularly limited, but it is random on the transparent substrate by applying a coating solution containing a metal component on the transparent substrate. A method of forming a reticulated metal layer is preferred. It is preferable to use such a method because it is excellent in that a random network structure can be formed using droplets in the coating liquid as a template. Preferably, a method of forming a random network metal layer on the transparent substrate by applying a coating solution containing a metal component on the transparent substrate and then heating is preferable.

  In addition, when a random network metal layer is formed on a transparent substrate by applying a coating solution containing a metal component on the transparent substrate, the coating solution used at that time includes a continuous phase and a discontinuous phase. Preferably, the continuous phase contains at least one metal component in the continuous phase, and the discontinuous phase is a droplet having an average droplet diameter of 0.1 to 5 μm. When a random network metal layer is formed on a transparent substrate using such a coating solution, the droplets of the discontinuous phase serve as a template, and the metal layer has a very fine random network opening. It is preferable because a metal laminated substrate can be formed. That is, the coating liquid is an emulsion having a continuous phase and a discontinuous phase, and the continuous phase contains at least one metal component, and the discontinuous phase is a droplet having an average droplet diameter of 0.1 to 5 μm. It is preferable to use an emulsion because the average opening diameter of the metal layer can be easily controlled in the range of 0.1 to 5 μm, and the average line width of the metal layer can be easily controlled to 0.01 μm to 2 μm.

  Here, the emulsion that is the coating liquid refers to a dispersion solvent in which both the solute and the solvent are liquid. In the W / O type emulsion, the continuous phase is an organic solvent, the discontinuous phase is an aqueous solvent, and O / In the W-type emulsion, the continuous phase is an aqueous solvent and the discontinuous phase is an organic solvent. The emulsion, which is the coating liquid of the present invention, contains a metal component-containing dispersion in which at least one metal component is dispersed in the solvent A and a solvent B that is hardly soluble in the solvent A, if necessary. It is an emulsion obtained by mixing. The solvent A and the solvent B may each be a single solvent or a mixed solvent. In the emulsion used as the coating liquid in the present invention, it is important that the solvent A in which at least one metal component is dispersed forms a continuous phase and the solvent B forms a discontinuous phase.

  When the solvent A is an aqueous solvent, the solvent B is composed of a solvent that is hardly soluble in the solvent A, and becomes an O / W (oil in water) type emulsion. On the other hand, when the solvent B is an aqueous solvent, the solvent A is composed of a solvent that is hardly soluble in the solvent B, and becomes a W / O (water in oil) type emulsion.

  As a method for preparing an emulsion solution that is a coating solution, mechanical emulsification methods such as a high-speed stirring device, a high-pressure emulsification device, an ultrasonic emulsification device, a membrane emulsification device, self-emulsification, phase inversion emulsification, liquid crystal emulsification, phase inversion Any of chemical methods such as temperature emulsification and D phase emulsification may be used, and examples thereof include a single method or a combination of plural methods.

  The emulsion, which is the coating solution, may be added to various additives such as a dispersant, a surface tension adjusting agent, a viscosity adjusting agent, a pH adjusting agent, an antiseptic, a chelating agent, an anti-oxidant, and the like within a range not impairing the effects of the present invention. Foaming agents, antioxidants and the like may be included. In order to improve the adhesion to the transparent substrate, the emulsion as the coating liquid may contain a known resin such as a thermoplastic resin, a thermosetting resin, or an ultraviolet curable resin. These various additives may be contained in either the continuous phase or the discontinuous phase, and may be contained in both the continuous phase and the discontinuous phase.

  The surfactant for forming the emulsion coating solution suitably used in the production method of the present invention is not particularly limited, and is a known anionic surfactant, cationic surfactant, or nonionic interface. Various surfactants such as an activator and an amphoteric surfactant can be used, and these can be used alone or in combination.

  The organic solvent used for the emulsion that is the coating solution may be any solvent that can be removed by drying at a temperature below the melting point of the thermoplastic resin film and is hardly soluble in an aqueous solvent. For example, toluene, xylene, benzene, hexane , Halogen solvents exemplified by heptane, octane, isooctane, petroleum ether, chloroform, cyclohexane, 1,1-dichloroethane, 1,2-dichloroethane, trichloroethane, etc., ketones exemplified by cyclohexanone, methylcyclohexanone, methyl isobutyl ketone, etc. And ester solvents exemplified by solvent, methyl benzoate, isobutyl acetate and the like. These solvents may be used alone or in combination of two or more.

  The emulsion form of the coating solution (that is, W / O type emulsion or O / W type emulsion) can be selected arbitrarily, taking into consideration the dispersibility of the metal component that is the main component of the coating solution and forms a network structure. May be selected as appropriate.

  As a step of applying the coating liquid on the transparent substrate, a known coating method such as reverse coating method, bar coating method, gravure coating method, rod coating method, die coating method, etc. can be used. This is not preferable because the average droplet size of the discontinuous phase may be out of the desired range.

  In addition, when the transparent substrate coated with the coating liquid is heated, the process may be heating at a temperature and time that can remove the solvent that forms the emulsion, but when a thermoplastic resin is used, It is necessary to heat at a temperature below the melting point of the thermoplastic resin. Further, in order to obtain a fine opening, it is necessary to have a temperature at which the droplets can be dried in a short time, and therefore heating at a temperature equal to or higher than the boiling point of the solution constituting the droplets. desirable. Moreover, since it may be impossible to obtain a favorable opening due to condensation when heating is performed in a high humidity environment, the humidity is preferably in the range of 20 to 60%, more preferably 20 to 40%.

  The shape of the metal component contained in the coating solution or the metal component contained in the continuous layer of the emulsion that is the coating solution may be particulate, fibrous, or plate-like, but is preferably particulate. The method for preparing the metal particles is not particularly limited. For example, (1) a chemical method in which metal ions are reduced to metal atoms in a liquid layer and grown into nanoparticles via atomic clusters, or (2) bulk metal A method of trapping particulate metal by evaporating in an inert gas with a cold trap, (3) breaking the metal thin film by heating the metal thin film obtained by vacuum deposition on the polymer thin film, The physical method etc. which disperse | distribute a metal nanoparticle in a polymer in a state can be used.

  The number average particle size of metal particles suitable as a metal component contained in the coating solution, particularly the number average particle size of metal particles suitable as a metal component contained in the continuous phase of the emulsion is in the range of 0.001 to 0.3 μm. More preferably, it is the range of 0.001-0.2 micrometer, More preferably, it is 0.001-0.1 micrometer. The particle size distribution of the metal particles may be large or small, and the particle size may be irregular or uniform, but if the particle size distribution is small and the particle size is uniform, random This is preferable because a simple network-like metal layer can be easily formed.

  Here, the number average particle diameter is an average particle diameter calculated based on the number of metal particles contained in the measurement sample, and the number average particle diameter of the metal particles is a copper mesh obtained by dispersing a solution in which the metal particles are dispersed. The metal particles were dropped and observed with a transmission electron microscope (H-7100FA type, manufactured by Hitachi, Ltd.), and the particle diameters of 100 metal particles selected arbitrarily were measured. The average particle size was taken.

The metal laminated substrate used for the window glass of the present invention preferably has a surface specific resistance value of 10 ⁶ Ω / □ or less. More preferably, it is 100Ω / □ or less, and further preferably 1Ω / □ or less. By reducing the surface specific resistance value of the metal laminated substrate, that is, by increasing the conductivity, the heat ray reflectivity is increased, which is preferable when such a metal laminated substrate is used as part of a window glass. In order to increase the conductivity, the metal layer is increased in conductivity by using a known method for increasing the conductivity, such as heat treatment, light treatment, energization treatment, acid treatment, etc., and the surface specific resistance value is reduced. Processing may be performed.

  Moreover, in order to reduce the surface specific resistance value by removing various additives contained in the metal layer, the metal layer may be cleaned using various solvents. However, when using the solvent, it is desirable to perform the treatment in a short time so as not to lower the adhesion between the metal layer and the transparent substrate.

  Moreover, you may make the surface specific resistance value of a metal laminated substrate small by laminating | plating a plating metal layer on a metal layer. A plating metal layer is a metal layer laminated | stacked by electroplating or electroless plating, and the electroconductivity of a metal laminated substrate becomes favorable by laminating | stacking a plating metal layer further on a metal layer. Since there is an acid treatment step as a pretreatment for laminating the plated metal layer, acid treatment is preferable as a method for reducing the surface specific resistance value of the metal laminated substrate.

  Although the metal which comprises a plating metal layer is not specifically limited, Cu, Ni, Cr, Zn, Au, Ag, Al, Sn, Pt, Pd, Co, Fe, In etc. can be used, 1 type or 2 types A combination of the above metals can be used. Among these, it is preferable to use Cu in terms of conductivity, electrolytic plating properties, and the like.

  Here, the measurement of the surface specific resistance of the metal laminated substrate is, for example, in a form conforming to JIS-K-7194-1994 after being left for 24 hours in a normal state (23 ° C., relative humidity 65%), The metal layer (or the plated metal layer on the metal layer) of the metal laminated substrate can be measured using Loresta-EP (manufactured by Mitsubishi Chemical Corporation, model number: MCP-T360).

In addition, although the surface specific resistance of a metal laminated substrate is so preferable that it is low, since it is considered difficult to make it practically less than 10 < ^-3 > ohm / square, a lower limit is considered to be about 10 < ^-3 > ohm / square.

  In the window glass of the present invention, it is important that the laminated order of the metal laminated substrate and the glass is laminated on the transparent substrate side of the metal laminated substrate with the glass. That is, the order is glass, the transparent substrate, and the metal layer, and the order in which the metal layer is outside the transparent substrate is desirable. For example, the order of glass, metal layer, and transparent substrate is not preferable because heat rays are absorbed by the transparent substrate disposed outside the metal layer and the heat ray reflection efficiency by the metal layer is reduced.

  The window glass of the present invention is intended to increase indoor heating efficiency by preventing indoor heat rays from leaking outside, so that the metal layer can be installed and used with the glass facing the indoor side and the glass facing the outside. desirable. If the glass is installed indoors and the metal layer faces outward, the outdoor heat rays are reflected, which is not preferable because warm heat rays are not incident indoors.

  Moreover, in the window glass of this invention, glass and a transparent substrate are laminated | stacked by the adhesion layer apply | coated to the opposite side (transparent substrate side) of the metal layer of a transparent substrate.

  The glass used for the window glass of the present invention to attach the metal laminated substrate may be a commonly used single plate glass or a multi-layer glass, but the multi-layer glass has a heat insulating performance. It is preferable from the viewpoint. The thickness of each glass in the multi-layer glass is not particularly limited to the thickness (width) of the air layer (heat insulating layer) between the glasses. For example, glass thickness 3 mm-air layer 6 mm-glass layer 3 mm, or glass thickness 3 mm -Multi-layer glass having a structure of air layer 12 mm-glass layer 3 mm is common. In addition, the glass thickness and air layer thickness of the multilayer glass can be designed as appropriate, and it is a multilayer glass of three or more layers, or one or both of the glasses are tempered glass or semi-tempered glass, Various heat insulating gases may be used as an alternative to air.

  As for the window glass of this invention, it is preferable that the average reflectance of a heat ray in the wavelength of 3-30 micrometers is 30% or more. More preferably, the average reflectance of heat rays at a wavelength of 3 to 30 μm is 40% or more. In addition, although the window glass is so preferable that the average reflectance of the heat ray in a wavelength of 3-30 micrometers is high, since it is thought that it is difficult to make it 90% or more realistically, an upper limit is considered to be about 90%. About window glass, it is preferable in order that heating efficiency can be improved, without letting an indoor heat ray leak outside by making the average reflectance of the heat ray in a wavelength of 3-30 micrometers into 30% or more.

  The heat transmissivity of the window glass can be calculated from the average heat reflectivity according to JISR3107. The higher the heat ray average reflectivity, the lower the heat transmissivity, that is, the higher the heat insulation performance. Increases heating efficiency. Here, the heat transmissivity indicates a numerical value representing the heat insulation performance of the building walls, floors, windows, etc., and the smaller this value, the less heat is transmitted and the higher the heat insulation performance, that is, the higher the heating efficiency. Show.

  A protective layer can be further provided on the window glass of the present invention. That is, a protective layer can be provided on the metal layer of the metal laminated substrate used for the window glass of the present invention. By providing the protective layer, it is possible to improve the scratch resistance of the metal layer as the heat ray reflective layer and improve the durability and weather resistance of the metal laminated substrate. In addition, since it is important to stack the transparent substrate side of the metal laminated substrate with glass, the order of laminating the metal laminated substrate and glass is, in the case of a window glass having a protective layer, glass, transparent substrate, metal layer, The protective layers are preferably laminated in this order. As the protective layer, a hard coat layer made of heat ray curable resin or ultraviolet curable resin can be laminated.

  As the heat ray curable resin suitably used for the protective layer, it can be used by appropriately selecting from conventionally known resins. For example, an acrylate polymer having a carbon-carbon double bond or a glycidyl group, Examples include saturated polyesters, isoprene polymers, butadiene polymers, epoxy resins, phenol resins, urea resins, melamine resins, vinyl resins, urethane resins, polyesters, polyamides, polycarbonates, polyimides, double-rate resins, and silicone resins.

  Examples of the ultraviolet curable resin suitably used for the protective layer include an ultraviolet curable composition such as urethane-acrylate, epoxy acrylate, and polyester-acrylate.

  As a method for forming the protective layer, a coating solution containing the above components is applied onto the metal layer by a known coating method such as a reverse coating method, a bar coating method, a gravure coating method, a rod coating method, a die coating method, or a spray coating method. The method can be used. And the thickness of a protective layer is 0.5-10 micrometers, Especially 1-5 micrometers is preferable. If the thickness of the protective layer is less than 0.5 μm, the scratch resistance function as a hard coat layer tends to be insufficient, while if it exceeds 10 μm, excessive characteristics increase the cost, which is not preferable.

  In this invention, when a transparent substrate is a thermoplastic resin film, it is preferable at points, such as being excellent in transparency, a softness | flexibility, and workability. The thermoplastic resin film as used in the present invention is a general term for films that are melted or softened by heat, and is not particularly limited, but representative examples include polyolefins such as polyester films, polypropylene films, and polyethylene films. Films, polylactic acid films, polycarbonate films, acrylic films such as polymethyl methacrylate films and polystyrene films, polyamide films such as nylon, polyvinyl chloride films, polyurethane films, fluorine films, polyphenylene sulfide films, and the like can be used.

  These thermoplastic resin films may be composed of homopolymers or copolymer polymers, but among these, polyester films, polypropylene films in terms of mechanical properties, dimensional stability, transparency, etc. Polyamide films are preferred, and polyester films are particularly preferred from the standpoint of mechanical strength and versatility.

  In such a polyester film, polyester is a general term for polymers having an ester bond as a main bond chain, and includes ethylene terephthalate, propylene terephthalate, ethylene-2,6-naphthalate, butylene terephthalate, propylene-2, It is preferable to use one having at least one component selected from 6-naphthalate, ethylene-α, β-bis (2-chlorophenoxy) ethane-4,4′-dicarboxylate as a main component. it can. These constituent components may be used alone or in combination of two or more. However, when quality, economy and the like are comprehensively judged, polyester having ethylene terephthalate as a main constituent, that is, polyethylene terephthalate is used. It is particularly preferable to use it. In addition, when heat or shrinkage stress acts on the substrate, polyethylene-2,6-naphthalate having excellent heat resistance and rigidity is more preferable. These polyesters may further be partially copolymerized with other dicarboxylic acid components and diol components, preferably 20 mol% or less.

  The intrinsic viscosity (measured in o-chlorophenol at 25 ° C.) of the polyester is preferably 0.4 to 1.2 dl / g, more preferably 0.5 to 0.8 dl / g. It is suitable for carrying out the invention.

  Further, in the thermoplastic resin, for example, polyester, various additives such as antioxidants, heat stabilizers, weathering stabilizers, ultraviolet absorbers, organic lubricants, pigments, dyes, organic or inorganic fine particles, Fillers, antistatic agents, nucleating agents and the like may be added to such an extent that the properties are not deteriorated.

  The thermoplastic resin film, such as a polyester film, is preferably biaxially oriented. Such a biaxially oriented polyester film is generally obtained by stretching an unstretched polyester sheet or film about 2.5 to 5 times in the longitudinal direction and in the width direction, and then performing heat treatment to complete the crystal orientation. Yes, it indicates a biaxially oriented pattern by wide-angle X-ray diffraction.

  The thickness of the thermoplastic resin film, for example, a polyester film is not particularly limited and is appropriately selected depending on the application and type, but from the viewpoint of mechanical strength, handling properties, etc., preferably 10 to 500 μm, More preferably, it is 38-250 micrometers, Most preferably, it is 75-150 micrometers. For example, when a polyester film is used as the substrate, a composite film by coextrusion may be used. On the other hand, a film obtained by bonding the obtained film by various methods can also be used.

In addition to the transparent substrate, the metal layer, and the protective layer, various layers may be laminated on the metal laminated substrate of the present invention. For example, although not particularly limited, an undercoat layer or the like may be provided between the transparent substrate and the metal layer to improve adhesion, and an adhesive layer or mold release may be provided on one or both sides of the transparent substrate. A layer, an adhesion-imparting layer, a weather-resistant layer, or the like may be provided. In addition, when forming various layers in the transparent substrate surface of the side which does not have a metal layer, various layers can be formed without being specifically limited.
[Method for measuring characteristics and method for evaluating effects]
The method for measuring the characteristics of the metal laminated substrate prepared in each example and the method for evaluating the effect are as follows.
(1) Droplet average particle size of the discontinuous phase The droplet average particle size of the discontinuous phase in the emulsion containing a metal component in the continuous phase is obtained by dropping several drops of the emulsion into the solvent used as the continuous phase. It measured with the laser diffraction scattering particle size distribution measuring apparatus (LS13320 by Beckman Coulter Co., Ltd.).
(2) Observation of random mesh-like metal layer The metal layer side surface of the metal laminated substrate was scanned with a scanning electron microscope (S-2100A type Hitachi scanning electron microscope, Hitachi, Ltd.) at a magnification of 500 times. Was observed, and it was confirmed whether or not a random mesh-like metal layer was formed or disconnected.
(3) Surface specific resistance of metal laminated substrate The surface specific resistance of the metal layer (or plated metal layer) of the metal laminated substrate was measured. After leaving the metal laminated substrate in a normal state (23 ° C., relative humidity 65%) for 24 hours, in that atmosphere, based on JIS-K-7194-1994, Loresta-EP (manufactured by Mitsubishi Chemical Corporation, model number: MCP) -T360).

However, the number of samples to be measured was one, five points were measured for each sample, and the average of the five points was defined as the surface specific resistance. In addition, the measurement upper limit in this measuring machine is 1.999 × 10 ⁶ Ω / □, and measurement is impossible when the surface specific resistance of the sample exceeds the upper limit.
(4) Total light transmittance of metal laminated substrate The total light transmittance is as follows. Fully automatic direct reading haze manufactured by Suga Test Instruments Co., Ltd. after leaving the metal laminated substrate for 2 hours in a normal state (23 ° C., relative humidity 65%). Measurement was performed using a computer “HGM-2DP”. The average value measured three times was defined as the total light transmittance of the metal laminated substrate. In addition, when the metal layer was laminated | stacked only on the single side | surface of the board | substrate, the electroconductive board | substrate was installed so that light may enter from the surface side which laminated | stacked the metal layer.
(5) Heat ray reflectivity and heat transmissivity In a Fourier transform infrared spectrophotometer (IR Prestige 21 manufactured by Shimadzu Corporation) attached with an integrating sphere for infrared spectroscopy, a single plate glass (3 mm thick), a transparent substrate, With respect to the window glass formed by attaching the metal layers in order, the reflectance measurement on the metal layer side of the window glass is performed in the range of 3 to 30 μm, and the average reflection of heat rays from the measured value according to JIS R3106 (established in 1985) The rate was calculated. Further, the heat transmissivity was calculated from the heat ray reflectivity according to JIS R3107 (established in 1998).
(6) Average opening diameter The surface of the metal layer of the sample was observed at a magnification of 500 using a digital microscope (manufactured by Keyence Corporation, VHX-200), and photographic data was stored. Next, the stored photographic data was selected and displayed on the screen, and brightness extraction was performed with a measurement tool built in the apparatus, and the line part was binarized to black and the opening part to white. In that case, it was set as the luminance range 195-255. Next, a white spot (noise) having an area of 400 pixels or less existing in the black part (line part) is removed by the “small grain removal” process, and an area of 400 pixels existing in the white part (opening part) by the “fill hole” process The following black spots (noise) were removed. Thereafter, an opening that was cut off by the frame of the screen and was not entirely displayed was converted into a black portion by “deletion” processing. Subsequently, the total area and perimeter were obtained by the “batch calculation” process. Thereafter, the average area was calculated from the total area / number of openings, and the average opening diameter was calculated from the following formulas (1) and (2).

Average area = π × r ² Formula (1)
Average opening diameter = 2r Formula (2)
(7) Average line width First, the surface of the metal layer of the sample was observed 500 times using a digital microscope VHX-200 manufactured by Keyence Co., Ltd., and photographic data was stored. The saved photo was opened with JTrim, the resizing ratio was 65%, and saved as a bitmap. The saved file was opened with Scion Image and binarized with the line portion being black and the opening portion being white. The binarized image lines, white spots in the openings, foreign matters, and the like were removed, and the total area and total length of the line portions were calculated (here, the unit is pixels). Thereafter, the average line width was calculated by the following formula (3).

Line width = 1.36 × (total area / total length) (1.36 is a coefficient) Expression (3)
(8) Number average particle diameter of metal particles The number average particle diameter of metal particles is determined by dropping a solution in which metal particles are dispersed onto a copper mesh and transmitting electron microscope (H-7100FA type, manufactured by Hitachi, Ltd.). ), The particle diameter of 100 arbitrarily selected metal particles was measured, and the average value was taken as the number average particle diameter.
(9) Analysis method of metal component The emulsion solution, which is a coating solution, is centrifuged at 10,000 rpm for 30 minutes using a centrifuge to separate the continuous phase and the discontinuous phase, and then included in each phase. The analyzed metal components were analyzed with an ICP emission analyzer.

Next, the present invention will be described based on examples.
Example 1
(1) Preparation of W / O type emulsion Silver particles (manufactured by Aldrich, particle size 30-50 nm) were coated with oleic acid and dispersed in 60 g of toluene. 20 g of an aqueous solution in which 0.5 g of the toluene solution and polyether-modified polydimethylsiloxane were dissolved was preliminarily stirred with a magnetic stirrer, and then at 12,000 rpm with a homomixer (TK HOMO MIXER, manufactured by Tokushu Kika Kogyo Co., Ltd.). The mixture was stirred for 5 minutes to form a W / O emulsion as a coating solution. The average droplet diameter (water droplet average particle diameter) in the W / O emulsion was 4 μm.
(2) Formation of metal laminated substrate and window glass adhered thereto The W / O emulsion was applied to a biaxially stretched polyethylene terephthalate film (Lumirror (registered trademark) U46 manufactured by Toray Industries, Inc.) and immediately at 150 ° C. A metal laminated substrate having a random network metal layer was formed by heating and drying for 2 minutes.

  After immersing the film in acetone for 10 minutes and drying at 25 ° C. for 3 minutes, the film was immersed in 25 ° C. 1N hydrochloric acid (manufactured by Nacalai Tesque) for 2 minutes, and the film was taken out and washed with water. Then, it dried at 150 degreeC for 2 minutes.

An adhesive layer was formed by applying SK dyne, which is an acrylic adhesive, on the surface opposite to the metal laminate surface of the metal laminate substrate, and an adhesive layer was adhered to a single plate glass to form a window glass.
(3) Evaluation of metal laminated substrate The obtained metal laminated substrate having a random network metal layer had an average opening diameter of 4 μm and an average line width of 1 μm. The total light transmittance was 63%, the surface specific resistance value was 50Ω / □, and the heat ray average reflectance of the window glass (single plate glass with a metal laminated substrate pasted) was 40%.
(4) Thermal conductivity of single glass and multi-layer glass provided with a metal laminated substrate The thermal conductivity of single glass (3 mm thickness) not provided with the metal laminated substrate is 6.0 W / m ² K The heat transmissivity of the window glass (single plate glass (3 mm thickness) in which the transparent substrate side of the metal laminated substrate was bonded with an adhesive layer) was 5.3 W / m ² K.

In addition, the thermal conductivity of the multilayer glass (single plate glass (3 mm thickness) + air layer (6 mm thickness) + single plate glass (3 mm thickness)) not provided with the metal laminated substrate is 3.4 W / m ² K. In contrast, a multi-layer glass (single glass (3 mm thickness) + transparent substrate + metal layer + air layer) in which the transparent substrate side of the metal laminated substrate is adhered to one inner surface of the multi-layer glass with an adhesive layer The thermal conductivity of (6 mm thickness) + single plate glass (3 mm thickness) was 3.1 W / m ² K.
(Comparative Example 1)
(1) Preparation of W / O type emulsion Silver particles (Aldrich, particle size 30 to 50 nm) were coated with oleic acid, and dispersed in 50 g of a toluene solution in which 1 g of sodium di-2-ethylhexylsulfosuccinate was dissolved. The toluene solution and 0.5 g of water were preliminarily stirred with a magnetic stirrer, and then stirred for 5 minutes at 12,000 rpm with a homomixer (TK HOMO MIXER, manufactured by Tokushu Kika Kogyo Co., Ltd.). An O-type emulsion was formed. The average droplet diameter in the W / O type emulsion was 0.05 μm.
(2) Formation of metal laminated substrate The W / O type emulsion was applied to a biaxially stretched polyethylene terephthalate film (Lumirror (registered trademark) U46 manufactured by Toray Industries, Inc.) and immediately dried by heating at 150 ° C. for 2 minutes. A metal laminated substrate was formed.
(3) Evaluation results The obtained metal laminated substrate was not formed with random mesh openings, and the heat ray reflectance was 40%, but the total light transmittance was 10%.
(4) Thermal transmissivity of single plate glass and multi-layer glass provided with metal laminated substrate Whereas the single tube glass not provided with metal multi-layer substrate has a heat transmissivity of 6.0 W / m ² K, the metal laminate The heat flow rate of the single plate glass in which the transparent substrate side of the substrate was bonded with an adhesive layer was 6.0 W / m ² K, and the effect as a window film for heat ray reflection was not observed. In addition, the thermal conductivity of the multilayer glass without the metal multilayer substrate was 3.4 W / m ² K, whereas the transparent substrate side of the metal multilayer substrate was adhered to one inner surface of the multilayer glass. The heat transmissivity of the multilayer glass stuck by the layer was also 3.4 W / m ² K, and the effect as a window film for heat ray reflection was not seen.

According to the present invention, it is possible to provide a heat ray reflecting window glass which can be produced by a simple and inexpensive method without using an expensive physical film forming method and which has excellent heat ray reflectivity.

Claims (7)

It is a window glass having a metal laminated substrate on one side of the glass,
The metal laminate substrate is a metal laminate substrate having a random network metal layer on a transparent substrate,
The metal layer has a mesh shape with an average line width of 0.01 μm to 2 μm and an average opening diameter of 0.5 μm to 10 μm.
A window glass, wherein a transparent substrate side of a metal laminated substrate is laminated with glass. 2. The window glass according to claim 1, wherein the surface resistivity of the metal laminated substrate is 10 ⁶ Ω / □ or less.   The window glass according to claim 1 or 2, wherein the average reflectance of heat rays at a wavelength of 3 to 30 µm is 30% or more.   The window glass according to any one of claims 1 to 3, wherein a random mesh-like metal layer is formed on the transparent substrate by applying a coating liquid containing a metal component on the transparent substrate. .   The coating liquid is an emulsion having a continuous phase and a discontinuous phase, the continuous phase contains at least one metal component, and the discontinuous phase is a droplet having an average droplet diameter of 0.1 to 5 μm. The window glass in any one of Claims 1-4 characterized by the above-mentioned.   The window glass according to claim 1, wherein the metal laminated substrate has a protective layer on the metal layer.   The window glass according to claim 1, wherein the transparent substrate is a thermoplastic resin film.