JP2013139107A - Laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transparent heat-reflective laminate that is higher in transparency, and lower in the shading coefficients than the past, and includes a protective film that does not damage the Low-E function.SOLUTION: The laminate comprises: a transparent heat reflection film of a low thermal emissivity that is formed of a transparent dielectric and the multilayer film of silver alloy and is transparent in the visible light; a transparent protective film; and the substrate, wherein the transparent protective film is an amorphous material fluororesin film that has the fluorine-containing aliphatic ring structure. The laminate has the excellent transparency, the near infrared barrier property, and the Low-E function (low radiative property), and is found having in well balance the transparent protective film function that defends the multilayer film from the mechanical and the chemical loading.

Description

  The present invention relates to a laminate that is covered with a transparent heat reflective film having high transparency and low thermal emissivity and protected with an amorphous fluororesin film having a fluorinated aliphatic ring structure.

  The transparent heat reflection film is a selective light transmission film that is transparent to visible light and has a high reflectance to infrared rays. It is a thin film that has a low thermal emissivity, prevents heat dissipation, exhibits heat insulation performance, and has an energy saving effect of about 30% through transparent openings such as windows while maintaining transparency. Moreover, the structure with high near-infrared light shielding performance has the effect of preventing inflow of heat due to the near-infrared light of sunlight and preventing unpleasant glare.

Transparent heat reflective film is a single layer film with a thickness of 200 nm or more such as tin oxide doped indium oxide (ITO, Indium Tin Oxide) with transparent conductivity. It uses infrared reflection by free electrons, transparent dielectric and silver There is a type in which a metal such as a multilayer film is used, and reflection of metal with visible light is prevented by a light interference effect and infrared light is highly reflected by the metal. Since a single layer film requires a thick film, there is a problem that the productivity is inferior and haze occurs. Multilayer film structures are frequently used in recent years because they can realize high productivity and excellent spectral characteristics by optimizing the structure. A three-layer film configuration such as TiO ₂ / Ag / TiO ₂ , ITO / Ag / ITO, or a five-layer configuration such as TiO ₂ / Ag / TiO ₂ / Ag / TiO ₂ is created on a glass or plastic film substrate, Used industrially.

In order to realize low thermal radiation (Low-E), it is necessary for these films to be exposed to the air layer side that radiates heat. In a single-layer building window glass, automobile glass, etc., the membrane surface faces the indoor side. In the case of double-glazed glass, the gap side surface of the counter glass is covered. Silver films are prone to oxidation when exposed to high temperatures and high humidity, and have environmental instability problems such as aggregation of silver atoms. Moreover, when exposed directly to the atmosphere, there is a problem in that the reaction proceeds with chemical substances such as sulfur and chlorine in the environment starting from the location, and deterioration proceeds.

  In the transparent heat reflecting film, the problem of instability of the silver film with respect to the environment has been improved by alloying silver with copper, gold or the like. An AgCu alloy obtained by adding several atomic percent of copper to silver improves the instability of silver and is therefore widely used industrially for transparent heat reflecting films. Furthermore, it has been reported that an AgCuAu alloy to which gold is added has an effect of improving transparency. However, the addition of gold is not used much industrially because of the high cost. By adding these metals to silver, the weather resistance of the transparent heat-reflecting film is improved, but there is a problem that light absorption increases with respect to visible light and transparency is lowered. In addition, there has been a problem of a decrease in reflectance with respect to infrared light from near infrared, and improvement has been desired. On the other hand, AgCuNd alloy, AgMgEu alloy and the like have excellent environmental resistance, optical properties are close to Ag, and show excellent spectral performance.

  When these transparent heat reflective films are exposed on the side of the air layer where heat is dissipated, a transparent protective film is coated to protect the film from mechanical loads such as scratches and chemical loads such as chemicals. is necessary. These transparent protective films are similar to protective films on the optical disk surface such as CD, DVD, and MOD that protect the film surface and / or substrate surface from mechanical and chemical loads under the same usage environment. However, a film such as an acrylic resin used for an optical disk for general purposes has a large light absorption in the heat (infrared) radiation wavelength region in the transparent heat reflecting film, and increases the heat emissivity, and the Low-E function and the heat insulation effect associated therewith. There was a problem to lose.

US Pat. No. 4,822,120 US Pat. No. 4,996,105 JP-A-7-66317 JP 2006-126861 A

  The problems to be solved are that the transparent heat reflecting film is highly transparent, has a Low-E function, and has a high near-infrared light shielding performance, and the film is subjected to mechanical loads such as scratches and chemical loads. It is realization of the structure covered with the transparent protective film which protects from and does not impair the low thermal emissivity.

  The present invention is a laminate comprising a transparent heat reflective film transparent to visible light and made of a multilayer film of a transparent dielectric and a silver alloy and a substrate, and the protective film of the multilayer film has a fluorine-containing aliphatic ring structure It is an amorphous fluororesin film having a laminate.

  The laminate of the present invention has a structure with a transparent protective film that protects the film from mechanical loads such as scratches and chemical loads, and does not impair the low thermal emissivity. In a more preferable configuration, the laminate has a surprisingly high near infrared light shielding property.

  The laminate of the present invention has a transparent protective film that protects the film from mechanical loads such as scratches and chemical loads, and does not impair the low thermal emissivity, and exhibits light coherence that produces selective light transmission, Further surprisingly, the present inventors have found a configuration having a Low-E function and having a shielding coefficient of 0.5 or less while maintaining a visible light transmittance of about 70% or more. The higher the visible light transmittance, the higher the transparency of the window visually, which is desirable. In addition, the present inventors have found a configuration in which the shielding coefficient reaches 0.4 or less while keeping the visible light transmittance at 70% or more. The visible light transmittance and the shielding coefficient in the present invention are values calculated based on Japanese Industrial Standard JIS A5759.

  The laminate in the present invention comprises a transparent heat reflective film transparent to visible light and comprising a multilayer film of a transparent dielectric and a silver alloy and having a low thermal emissivity, an amorphous fluororesin protective film having a fluorine aliphatic ring structure, and a substrate. It becomes more. More preferably, the laminate has a transparent dielectric / silver alloy (1) / transparent dielectric / silver alloy (2) / transparent dielectric film / amorphous fluororesin film structure from the substrate side, and the silver alloy The film thickness of (2) is in the range of 1.2 times to 2 times the film thickness of the silver alloy (1).

The laminate in the present invention is composed of an amorphous fluororesin protective film having a fluoroaliphatic ring structure. The amorphous fluororesin having a fluoroaliphatic ring structure used in the configuration of the present invention has been conventionally applied to antireflection films, optical fiber cores, cladding materials, etc. due to transparency in the visible to near-infrared wavelength region. However, there was no application form that actively utilized the optical characteristics in the infrared region industrially. As a result of intensive investigation of protective films that prevent heat dissipation from transparent openings such as windows, protect transparent heat-reflective films from mechanical and chemical loads, and maintain low heat emissivity. It has been surprisingly found that the amorphous fluororesin has a transparent window centered on the wavelength of 10 μm necessary for the heat insulation of the window and further in the wavelength range of 8 μm to 12 μm.

  The protective film constituting the laminate of the present invention is made of an amorphous fluororesin having a fluoroaliphatic ring structure. The amorphous fluororesin having a fluoroaliphatic ring structure may be any one having a transparent window in the wavelength range of 8 μm to 12 μm. For example, there is a perfluoropolymer. The cyclized polymer may be a copolymer with another copolymerizable monomer other than the structure in which the monomer is repeatedly polymerized. In order to increase the adhesion to the substrate, the terminal functional group may be an alkoxy group such as COOH, CONH, or Si. Furthermore, it is more preferable that the functional group contained in the structure is a compound having substantially no hydrogen atom. The thickness of the protective film is not particularly limited, and examples thereof include 1 μm to 10 μm.

  The protective film constituting the laminate of the present invention is made of an amorphous fluororesin having a fluoroaliphatic ring structure, but in order to further increase the adhesion to the base, a coupling agent such as a silane coupling material is applied to the base. Alternatively, a thickness of about several nm to several tens of nm may be provided. In addition, the protective film may be laminated with another protective film of about submicron to several μm, for example, an acrylic film, or fine particles such as titanium oxide may be included in the protective film as long as the effects of the present invention are hardly impaired.

  The transparent dielectric in the present invention is not particularly limited as long as it is a solid substance that is transparent to visible light and has a high refractive index, and examples thereof include metal oxides, metal nitrides, metal sulfides, and metal carbides. These metal compounds may be transparent electrical insulators and / or transparent semiconductors. Examples of the metal oxide include one or more metal oxides selected from the group consisting of titanium, zirconium, zinc, indium, tin, cadmium, and silicon. Examples of the metal nitride include nitrides such as silicon and aluminum. Examples of metal sulfides include sulfides such as zinc. Examples of the metal carbide include carbides such as silicon. Further, diamond-like carbon (DLC, Diamond Like Carbon) is also exemplified.

These oxides, nitrides, sulfides and / or carbides may be used alone or as a mixture. The refractive index is preferably 1.6 or more, and particularly preferably 1.8 or more, from the antireflection effect of the metal film. These high refractive index films may be used alone or in a laminated structure. A laminated structure of a high refractive index film and a low refractive index film such as SiO ₂ or MgF may be substantially a high refractive index film. AlSlN is particularly preferable from the viewpoint of environmental stability of the laminate and small film strain.

  The film thickness of these transparent dielectric films is not particularly limited as long as selective light transparency can be realized by the interference effect, but is preferably 10 nm or more and 500 nm or less, particularly preferably 30 nm or more and 200 nm or less.

  The silver alloy film in the present invention is not particularly limited as long as it is transparent to visible light by being laminated with the dielectric film, has a high reflectance to infrared light, and has a low thermal emissivity. In order to improve, at least one of the silver alloys is preferably made of a silver alloy containing one or more elements of neodymium, europium, gold, copper, and magnesium. In the present invention, an element such as titanium, chromium or rare earth may be further added to the silver alloy. The trace amount additive contained in such a film is not limited to these. In order to be used widely industrially including cost, including excellent performance, an alloy close to Ag such as an AgCuNd alloy, particularly an AgMgEu alloy is preferable because of its excellent transparency and environmental properties.

  The thickness of these metal films is not particularly limited as long as selective light transparency can be realized by the interference effect, but is preferably 7 nm to 24 nm, and particularly preferably 10 nm to 22 nm.

  Between these metals and the dielectric film, improvement of metal environmental resistance, reduction of film-forming damage to the metal film surface during dielectric production, improvement of adhesion between metal and dielectric film interface, etc. For the purpose, a very thin film such as Ti or Nichrome may be laminated.

  The substrate in the present invention is not particularly limited as long as it is transparent and can hold the transparent heat reflection film, and examples thereof include inorganic materials such as glass and polymer moldings such as plastics.

  The organic polymer compound constituting the polymer molding is not particularly limited as long as it is a transparent organic polymer compound excellent in heat resistance, but usually has a heat resistance of 80 ° C. or higher, preferably 100 ° C. Polyimide, polyethersulfone, cycloaliphatic polyolefin resin, polyethylene terephthalate, polyethylene 2,6 naphthalene dicarboxylate, polydiallyl phthalate, polycarbonate, and aromatic polyamide, polyamide, polypropylene, cellulose triacetate, etc. . These can be used as homopolymers, copolymers, alone or as a blend.

  Although the shape of such a polymer molded product is not particularly limited, it is usually preferably in the form of a sheet or film, and in particular, the one on the film can be rolled up and can be continuously produced. preferable. Further, when a film-like material is used, the thickness of the film is preferably 6 μm or more and 500 μm or less, and more preferably 12 μm or more and 200 μm or less.

  In the present invention, the laminate preferably comprises a transparent dielectric / silver alloy (1) / transparent dielectric / silver alloy (2) / transparent dielectric film / protective film from the substrate side, and the silver. The film thickness of the alloy (2) is in the range of 1.2 to 2 times the film thickness of the silver alloy (1). The film thickness of the silver alloy (1) layer is from 7 nm to 16 nm in terms of transparency, and the film thickness of the silver alloy (2) layer is from 15 nm to 24 nm, particularly preferably the metal (2 ) Layer thickness is 18 nm or more and 20 nm or less. In the laminated body having these film thickness configurations, the phase of the reflection of near-infrared light at the multilayer interface is disturbed without substantially impairing the transparency in the visible region, and this effect sharply reflects the reflection in the near-infrared region. This is because a configuration in which the shielding coefficient reaches 0.5 or less has been found. Moreover, it is because the structure in which the shielding coefficient reaches 0.4 or less was found while maintaining the visible light transmittance at 70% or more.

  Furthermore, by forming a pattern in which the film thickness of the silver alloy (2) is partially different within the film surface of the silver alloy (2), the pattern of transmission and / or reflection color is superimposed on the transparent heat reflection film. You can do that. A method for forming this pattern is not particularly limited, and there are a method of using a mask in forming a metal film, a method of applying a patterned nucleation seeds agent for accelerating film formation, and the like. Needless to say, patterning for increasing radio wave transmission is also included.

  In the laminate of the present invention, a transparent heat reflective film is formed on the substrate. The structure of these transparent heat reflection films is a dielectric / metal / dielectric / protective film, and more preferably a dielectric / metal / dielectric / metal / dielectric / protective film that can realize selective light transmission by interference effect. It consists of a membrane configuration. However, the configuration of the dielectric / metal / dielectric / metal / dielectric / metal / dielectric / protective film, which is an extension of the concept of the present configuration, may be any configuration that can realize the concept of the present invention. The dielectric may be composed of a laminated film or the like.

  Even if an undercoat layer is added between the substrate and the dielectric to increase adhesion and / or an inorganic coat layer is added on the uppermost dielectric to further increase the protective performance. Needless to say, it is good.

  The laminate of the present invention is used as a single-layer glass or a multi-layer glass, and as a plastic film, a form in which the film is bonded to a single-layer glass, or a multi-layer glass.

  The transparent heat reflective film of the present invention is formed by various industrial production methods. Although such a manufacturing method is not particularly limited, a method for producing the thin film may be a wet method and / or a physical vapor deposition method (PVD, Physical Vapor Deposition) such as a vacuum deposition method using a vacuum, a sputtering method, And / or chemical vapor deposition (CVD) using a reactive gas. Rather than industrial productivity, metal and dielectric films can be consistently and continuously formed. High-frequency and / or DC bipolar magnetron sputtering, dual magnetron sputtering, and high-speed film formation and silver alloy stability. From this point, the DC magnetron sputtering method is preferable. It goes without saying that depending on the application, a combination of an ion plating or CVD method and / or a wet method such as a sol-gel may be used in consideration of cost. For forming the protective film constituting the laminate of the present invention, a general wet coating method including a spin coating method, a dip coating method, a spray method and the like is used.

  A transparent heat-reflective film transparent to visible light and made of a transparent dielectric and metal multilayer film and having a low thermal emissivity, and the protective film of the multilayer film is an amorphous fluororesin film having a fluorine-containing aliphatic ring structure A laminate comprising a protective film and a substrate, wherein the laminate is preferably composed of transparent dielectric / silver alloy (1) / transparent dielectric / silver alloy (2) / transparent dielectric film from the substrate side. And the film thickness of the silver alloy (2) is in the range of 1.2 to 2 times the film thickness of the silver alloy (1), and the laminated body has a visible light transmittance of 70% or more to shield. Excellent transparency, high-performance near-infrared light blocking property, low thermal emissivity, and protective film that protects against mechanical and chemical loads, characterized by a coefficient of 0.5 or less. .

FIG. 1 shows a cross-sectional view of one embodiment of the laminate of the present invention. A multilayer film was formed by sputtering using a direct current bipolar magnetron sputtering apparatus. The substrate 1 is a biaxially stretched PET (polyethylene terephthalate) film substrate having a thickness of 75 μm. After the substrate was placed in the vacuum chamber, the vacuum chamber was evacuated to 2.7 × 10 ⁻⁴ Pa. Thereafter, argon gas mixed with 30% nitrogen was introduced into the vacuum chamber from the gas inlet, and the pressure was set to 5.3 × 10 ⁻¹ Pa. An AlSiN film 2 was formed with a sputtering power of 150 W using a target of Al ₇₀ Si ₃₀ (atomic%) having a diameter of 10.2 cm. Next, the target is an Ag _99.1 Mg _0.5 Eu _0.4 (atomic%) alloy with a diameter of 10.2 cm, and argon gas (purity 99.999%) is introduced to form a gas of 5.3 × 10 ⁻¹ Pa. In the atmosphere, the AgMgEu alloy film 3 was formed with a sputtering power of 50 W. Next, argon gas mixed with 30% of nitrogen was again introduced into the vacuum chamber to 5.3 × 10 ⁻¹ Pa. An AlSiN film 4 was formed with a sputtering power of 150 W using a target of Al ₇₀ Si ₃₀ (atomic%) having a diameter of 10.2 cm. By repeating these operations, a multilayer of AlSiN (47) / AgMgEu (11) / AlSiN (94) / AgMgEu (18) / AlSiN (47) (wherein the parentheses indicate the unit of nm in the film thickness) A film was formed. In addition, as a result of analyzing the composition of the produced AgMgEu film with a wavelength dispersive X-ray fluorescence apparatus manufactured by Rigaku Corporation, an alloy film of Ag _99.1 Mg _0.5 Eu _0.4 (atomic%) is formed. I understood. Further, a 9% fluororesin solution (CTL-809A, manufactured by Asahi Glass) was applied with a spin coater and baked at 120 ° C. for 10 minutes to form an amorphous fluororesin film 7 having a thickness of 5 μm. This sample is referred to as Example 1.

The laminate was irradiated with light from the film surface using a Shimadzu UV-3150 spectrometer, and the transmittance (%) and reflectance (%) were measured at a wavelength of 220 nm to 2200 nm. The transmittance was measured at normal incidence, and the reflectivity was measured at an oblique incidence of 6 degrees from the direction perpendicular to the film surface. The spectrum of the laminate showed selective light transmission, visible light transmittance of 78%, and excellent heat shielding performance with a shielding coefficient of 0.45. The approximate laminate infrared spectrometer by (manufactured by JASCO Corporation FT-IR device) to measure the reflection spectrum in the wavelength range of 4000 cm ^-1 from 400 cm ^-1. A slight absorption of about 2% was observed in the vicinity of 1300 cm ⁻¹ , but almost no absorption was observed in the wavelength range of 8 μm to 12 μm, and it was found that the protective film functions as a window of thermal emissivity.

As Comparative Example 1, instead of forming the amorphous fluororesin film in Example 1, an ultraviolet curable acrylic resin (SD2200, made by DICK) was applied with a spin coater, and a film having a thickness of 5 μm was formed by curing by ultraviolet irradiation. A multilayer film was prepared under the same conditions except that the formation was different. The approximate laminate infrared spectrometer by (manufactured by JASCO Corporation FT-IR device) to measure the reflection spectrum in the wavelength range of 4000 cm ^-1 from 400 cm ^-1. In the wavelength region of 8 μm to 12 μm, a large number of absorptions of 20% to 30% were observed, and it was found that the film did not function as a window of thermal emissivity.

  As is clear from these results, the laminate of the present invention is transparent to visible light necessary for transparent heat insulation, has a Low-E function in the infrared light region, and is a window of a moving object such as a building window or an automobile. In the case where the membrane surface is installed facing the indoor side, a structure that exhibits surprising performance with the excellent mechanical and chemical protection functions of fluororesin has been realized.

  As is clear from this example, the laminate of the present invention is an excellent transparent heat reflector having high light transmittance and infrared reflectance. In addition, this invention is not restrict | limited by a present Example.

It is explanatory drawing of Example 1 which showed the implementation structure of the laminated body.

1 Substrate 2 AlSiN film 3 AgMgEu alloy film 4 AlSiN film 5 AgMgEu alloy film 6 AlSiN film 7 Amorphous fluororesin film

Claims (3)

  A laminated body composed of a transparent heat reflecting film, a transparent protective film, and a substrate transparent to visible light and made of a transparent dielectric and a silver alloy multilayer film, wherein the transparent protective film of the multilayer film is a fluorine-containing aliphatic ring. A laminate comprising an amorphous fluororesin film having a structure.   The laminate has a structure of transparent dielectric / silver alloy (1) / transparent dielectric / silver alloy (2) / transparent dielectric film / amorphous fluororesin film from the substrate side. The film thickness is in the range of 1.2 to 2 times the film thickness of the silver alloy (1), the visible light transmittance of the laminate is 70% or more, and the shielding coefficient is 0.5 or less. The laminate according to claim 1. The laminate according to claim 1 or 2, wherein at least one of the silver alloys comprises a silver alloy containing one or more elements of neodymium, europium, gold, copper, and magnesium.