JPS6338515B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a window structure in which a transparent heat insulating film is applied to multiple windows such as double-glazed windows or triple-paned windows to improve the heat insulation properties of the window. and regarding superior window structures.

In recent years, energy conservation has become a serious issue, and various techniques have been proposed for controlling heat radiation from windows, walls, ceilings, floors, etc. in buildings. When it comes to windows, single-glazed windows are replaced with double-glazed windows to improve the insulation effect, and in cold regions such as Hokkaido and Scandinavian countries, one side of double-glazed glass is improved to double-glazed glass and triple-glazed windows are replaced with double-glazed windows. The idea of using it as a window is about to take shape. However, such methods require high construction costs, and it is not clear whether they will become widespread.

The present inventor has developed a transparent heat insulating film that is transparent to visible light and has the ability to reflect low-temperature radiation emitted from stoves, other heating appliances, indoor walls, etc. It was discovered that when applied to glass windows, it provides the same insulation effect as double-glazed windows. Then, when this transparent heat insulating film was applied to a double-glazed window, it was found that the heat insulating effect changes depending on the structure of the transparent heat insulating film and the structure of the window to which this film is applied. Furthermore, if a protective film is provided on the surface of a transparent heat insulating film to increase its scratch resistance as a window, the reflective performance of low-temperature radiation will be reduced. The heat insulation effect changes depending on the air flow velocity when air is passed between the glass plates of double-glazed windows to prevent condensation, and the amount of energy acquired varies depending on the installation position of the transparent heat insulation film. I found out some things.

The present invention was achieved as a result of studying the preferred performance and form of a window structure when applying a transparent heat insulating film to double-glazed windows.

That is, the present invention provides a transparent plate serving as an inner window facing indoors, another transparent plate provided through a space from the transparent plate serving as an outer window, a window frame for holding these transparent plates, and a window frame for holding the transparent plate, and In a multi-layer window formed from a transparent heat insulating film, the transparent heat insulating film comprises a plastic film base material and a processed layer provided on the base material, which includes a thin film of a high refractive index dielectric, a thin film of metal, and a protective film. The transparent film is provided so that the plastic film base material is in close contact with the surface of the transparent plate serving as the inner window on the space side, if necessary via an adhesive or adhesive; the transparent heat insulating film has a solar energy absorption rate of 10% or more,
The sum of solar energy transmittance and solar energy absorption rate is 50% or more, and the visible light transmittance is 50% or more; the thickness d (μm) of the protective film is determined by the infrared absorption capacity Q (%) and water permeability. A (g/100cm ² /24hr/
The present invention is a multi-layer window having a transparent heat insulating film, characterized in that it satisfies the following relationship: Q.d≦120 d/A≧1 at 10 μm/1 atm).

The present invention selects a transparent heat insulating film for multi-layered windows that has a high visible light transmittance with solar energy transmittance and solar energy absorption within a specific range, and also uses this transparent heat insulating film as a transparent plate that becomes an inner window. The insulation effect was enhanced by installing the Furthermore, the multiple windows of the present invention include:
By specifying the thickness of the protective film layer of the transparent heat insulating film based on infrared absorption ability and water permeability, it has low infrared absorption and excellent durability.

The present invention will be explained using the drawings. Figure 1 shows the multiple window of the present invention (the figure shows a link to a double window)
FIG. The multi-layer window of the present invention includes a transparent plate 20 serving as an inner window facing the room, and a space 25 between the transparent plate and the transparent plate 20.
Another transparent plate 22 serving as an external window provided through the
Window frame 16 and transparent plate 2 that hold these transparent plates
It is formed from a transparent heat insulating film 30 provided on the space side of 0. A pad 12 that limits the amount of ventilation between the room and the space or makes it airtight is provided on the outer periphery of the window frame on the inner window side. Air from outside is introduced into the space 25 through the filter 14.

FIG. 2 is an enlarged view showing a transparent heat insulating film attached to a transparent plate, and shows a cross section of the transparent heat insulating film. The transparent heat insulating film that is attached to the transparent plate 20 that serves as the interior window on the indoor side with adhesive or adhesive 31 includes a thin film 34 of a high refractive index dielectric material and a thin film 3 of metal on one side of the plastic film 32.
6. Thin films 38 of high refractive index dielectric material are laminated in this order, and a transparent protective layer 39 is further provided so as to be in contact with the outer high refractive index dielectric material 38. and,
The transparent heat insulating film is attached so as to be in close contact with the transparent plate.

In the present invention, a multi-layer window is one in which at least two transparent plates are provided facing each other with a space between them, and a space is defined by these and a window frame body provided as necessary. It is.

For example, specifically, a double-glazed window consisting of a single-glazed window and a single-glazed window, a window where one or both of them is composed of double-glazed glass or triple-glazed glass, or a window where single-glazed glass is triple-layered. and double-layered windows.

Transparent plates include plates made of plastic and glass, while window frames include metal such as aluminum,
Examples include wood, plastics, etc. alone or a combination thereof.

A multi-panel window may be one in which a plurality of panels come together to move left and right to open and close, and a plurality of panels together rotate around one side of the window frame to open and close as needed. Furthermore, the panel may be one in which other panels are opened and closed by rotating around one side of the panel (a so-called linked window).
Alternatively, a plurality of panels may be integrally fitted into the window frame, and some or all of these panels may be removable. Among these,
"Linked windows" or "inset type" are easy to achieve airtightness of the inner window due to the window structure, and the gap between the inner and outer windows can be opened as necessary. It is easy to apply the transparent heat insulating film and to clean the inside of the window, so it can be preferably applied to the present invention.

A mode in which the transparent heat insulating film constituting the multilayer window of the present invention is provided is that it is attached to the outward facing surface of the transparent plate on the indoor side in a space formed by at least two transparent plates and a window frame. The plastic film layer, which is the base material of the transparent heat insulating film, is attached to the transparent plate through an adhesive so that it is in close contact with the transparent plate.

As for the function of windows, it is sometimes desirable to prevent indoor heat from escaping to the outside, while at the same time allowing as much solar energy into the room as possible.
The window structure of the present invention is excellent in having such a function. In particular, from the perspective of thermal efficiency, a material with high thermal conductivity (in the present invention, a thin film of a high refractive index material, a thin film of metal) and a transparent plate (glass The plastic film layer, which has low thermal conductivity, must be brought into close contact with the glass plate.

In addition, the transparent heat insulating film is required to have a solar energy absorption rate of at least 10%, and in order to make this solar energy absorption function effectively, the transparent board (inner window) on the indoor side must be transparent. It is necessary to apply a heat insulating film. When constructed in this way, most of the amount of solar energy transmitted and the amount of solar energy absorbed is taken into the room.
If a transparent heat insulating film is attached to a transparent plate serving as an exterior window, most of the absorbed solar energy will be lost to the outdoors. Another advantage of the transparent heat insulating film, which has a solar energy absorption rate of 10% or more, is that it increases the surface temperature of glass, etc., thereby avoiding condensation, and it also increases the temperature of the interior of the room by increasing the temperature of the surface of the glass, etc., thereby avoiding condensation. Once the heat energy is absorbed by the window material, the heat is dissipated and supplied into the room by low-temperature radiation.
Another advantage is that the living environment will be further improved.

The transparent heat insulating film attached to the space side (opposite the indoor side) of the transparent plate that is the inside of the multi-layer window consists of a plastic film base material, a metal thin film processed on the surface of the base material, and a high refractive index dielectric thin film. and a transparent protective film. These structures can be appropriately selected from known materials so as to have functions having the characteristics of the present invention. Further, the thickness of the thin film or protective film can be determined as appropriate.

The plastic film used as the base material is required to be transparent, as well as having dimensional stability and mechanical strength.
Therefore, wholly aromatic polyamides, polyethylene terephthalate, etc., which have excellent heat resistance and dimensional stability, are preferred.

A thin film of metal or metal oxide is laminated on one side of this plastic film by vapor deposition or the like.

As metals, gold, silver, copper, gold-silver alloys, silver-copper alloys, gold-silver-copper alloys, and gold-copper alloys are usually used, and as metal oxides, In ₂ O ₃ , SnO ₂ and
Cd ₂ SnO ₄ etc. are used, but are not necessarily limited to these. Although these metal or metal oxide thin films may be provided as individual thin films, it is preferable to use them in combination with a high refractive index dielectric thin film in order to improve transparency.

As a high refractive index dielectric, the refractive index is 1.6 or more,
Preferably, the transparent dielectric material has a dielectric strength of 1.8 or more, such as titanium dioxide, titanium oxide, bismuth oxide, hardened zinc, tin oxide, and indium oxide.

Furthermore, the transparent heat insulating film used in the multi-layer window of the present invention requires a protective film as described below.

The transparent heat insulating film used in the present invention is a composite film in which a base material, a high refractive index dielectric thin film, a metal thin film, a high refractive index dielectric thin film, and a protective film are laminated in the following order. Typical examples include (a) PET film/TiO ₂ /Ag/TiO ₂ /protective film (b) PET film/TiO ₂ /Ag-Cu/TiO ₂ /protective film (c) PET film/TiO ₂ /Ag-Au /TiO ₂ /Protective film (d) PET film /TiO ₂ /Ag―Au―Cu/
TiO ₂ / Protective film (E) PET film / Au / TiO ₂ / Protective film (F) PET film / TiO ₂ / Au / TiO ₂ / Protective film (G) PET film / Au / Protective film (H) PET film / Examples include TiO ₂ /Au/protective film (Li) PET film/TiO ₂ /Cu/TiO ₂ /protective film.

A transparent heat insulating film must have a solar energy transmission amount of 50% or more, which is the sum of solar energy transmittance and solar energy absorption rate, and must also have a visible light transmittance of 50% or more and a solar energy absorption rate of 10. % or more.

When the amount of solar energy transmitted through the window structure of a building is 50% or more, there is generally less energy leakage when looking at the indoor energy balance, resulting in an energy-saving effect.

In addition, the visible light transmittance is directly related to the brightness of the room, and when the visible light transmittance is less than 50%, it gives a dark feeling to the occupants of the room, and when it is less than 30%, it gives a feeling of oppression.

When applying transparent heat insulating film to window glass,
Scratch resistance is required since it is susceptible to damage during use and when cleaning the windows. This scratch resistance is achieved by providing a transparent hard protective layer on top of a thin film of high refractive index dielectric material or thin metal film, which is the processed layer of the transparent heat insulating film.

Conventionally known polyester copolymers, styrene resins, acrylate resins, etc. are transparent and hard polymers that seem to be suitable for protective layers, but these are not necessarily satisfactory in terms of their heat insulation effects. . The material of the protective film that can actually be applied is as follows:
It is preferable that the infrared absorption ability Q is 30% or less. Further, a limited range is suitable for the film thickness, and the relationship between the film thickness d (μm) and the infrared absorption capacity Q is essential: Q×d≦120. More preferably, Q×d is
It is 60 or less, more preferably 40 or less.

Furthermore, since dew condensation may occur on the window surface when using the material for the protective film, the waterproof effect of the metal thin film or metal oxide thin film is required as well as the scratch resistance. Protective films with low waterproofing effects often cause speckled stains on transparent heat insulating films.

Therefore, it is preferable that the material forming the protective film has properties that do not allow water to pass through, and it is desirable that the material has a low water permeability and has a large film thickness within a range that does not impair transparency or heat insulation effect. Now, the water permeability of the material that forms the protective film is A (g/100cm ² /24hr/10μm/
1 atm), a film thickness that satisfies the relationship d/A≧1 is required.

The water permeability here is a measurement of the amount of water in liquid phase (room temperature) that permeates through a film with a thickness of about 10 μm under 1 atmosphere, and the details will be described later.

The protective film is required to have a material and a film thickness that simultaneously satisfy the above two equations.

Suitable materials for such a protective film include, for example, homopolymers of polyolefins such as polyethylene, polypropylene, 4-methylpentene-1, and copolymers such as ethylene-propylene rubber; polyacrylonitrile, polymethacrylonitrile, acrylonitrile-styrene, polybutadiene, etc. Examples include vinyl homopolymers or copolymers such as polyisoprene rubber. These polymers can be subjected to crosslinking, crystallization, and even multilayer formation in order to harden the surface. In addition, as a means to further increase the solar energy absorption rate of the transparent heat insulating film, a metal oxide with high near-infrared absorption ability is added to the plastic film base material and the adhesive or pressure-sensitive adhesive used to closely adhere it to the transparent plate. Can be added.

As a window structure to which the present invention can be applied, a transparent plate facing indoors (inner window) and a transparent plate facing outdoors (outer window)
In addition to double-glazed windows, triple- or quadruple-paned windows with a large number of transparent panels may be used. As with double-glazed windows, a transparent heat insulating film can be provided on the surface of the transparent plate that serves as the inner window.

In order to increase the solar energy absorption efficiency of the multi-layer window of the present invention, the air flow in the space formed by at least two transparent plates and the window frame must be small. That is, the air velocity within this space must be at most 0.5 m/sec. This is because the thermal energy absorbed by the transparent insulating film
Heat is transferred by the air flow in the room, resulting in the effect of increasing the temperature in the room. Therefore, increasing the air flow velocity along the windows in the room and lowering the air flow velocity within the multi-paned window space provides an effective heat absorption effect.

Note that the structure of the multi-layer window of the present invention is preferably such that air with high humidity (moisture content) on the indoor side does not flow into the space. The inflow of moisture-rich air into a space tends to cause condensation, and to avoid this, it is desirable to reduce or close ventilation from the room. Of course, dew condensation can also be avoided by creating a multi-pane structure that allows a larger amount of outdoor air to flow in than the amount of indoor air.

Infrared absorption ability is determined as follows. By depositing silver on polyester film
Provide a film thickness of 3000 Å or more. This silver layer has a wavelength of 4~
Reflects 100% of infrared light at 20μm. A polymer compound is provided on this silver layer to a thickness of 2 μm. Infrared rays are thus irradiated from the polymer compound layer of this laminate, and the reflectance R (%) of each wavelength is measured. On the other hand, if the black body radiation energy of each wavelength at 300㎜ is E, then the infrared absorption ability for wavelengths of 4 to 20 μm is given by the following formula.

Infrared absorption ability Q (%) = 100 - ( ₂₀ 〓 ⁴ (R x E) / ₂₀ 〓 ⁴ E) It is necessary to select a polymer compound whose infrared absorption ability obtained from the above formula is 30% or less.

Solar energy transmittance, solar energy absorption rate, and visible light transmittance were determined as follows. Let the transmittance and absorption rate at wavelength λ (mμ) be T (%) and A (%), respectively. Also, if the intensity of solar energy at wavelength λ is G, then It can be found as

The amount of water passing through the polymer membrane forming the protective layer is determined as follows.

A solution obtained by dissolving a polymer to be used as a protective film in an appropriate solvent is applied onto a glass substrate or a polyester film using a bar coater, dried, and then the dried coating film is peeled off from the substrate. A film is obtained by melting the molecules. This film was sandwiched between two disc-shaped filter papers, and then
A film sandwiched between filter paper is placed on a mesh stainless steel wire gauze, packing is placed around the periphery, the film is attached to a cylindrical body, and the film is pressurized with 1 atmosphere of nitrogen gas to measure the water permeability through the film.

Example 1 A 250 Å titanium oxide thin film layer was applied as the first layer to a 50 μm thick biaxially stretched polyethylene terephthalate film with a light transmittance (500 nm) of 86%, and a 250 Å titanium oxide thin film layer as the second layer.
A 140 Å metal thin film layer consisting of silver and copper (the weight ratio of silver and copper is 90:10) and a 300 Å titanium oxide thin film layer as the third layer were sequentially laminated (the obtained transparent heat insulating film is hereinafter referred to as transparent heat insulating film). (abbreviated as Film-1).

Each titanium oxide thin film layer was formed by applying a solution consisting of 3 parts of a tetramer of tetrabutyl titanate, 65 parts of isopropyl alcohol, and 32 parts of n-hexane using a percoater and heating at 100° C. for 20 minutes.

The metal thin film layer is made of an alloy of silver and copper (silver content 90% by weight, copper content 10% by weight) in a vacuum of 5 × 10 ^-5 Torr.
was heated in an aluminum crucible and vacuum-deposited.

A polyacrylonitrile copolymer (a copolymer containing 10 mol% of 2-hydroxyethyl methacrylate) having an infrared absorption capacity Q of 14% is dissolved in a cyclohexanone solvent as a protective film layer on top of the transparent heat insulating film-1, and this solution is coated. In particular, a protective film layer with a thickness of 3 μm was provided. This transparent thermal insulation film with a protective film has a solar energy transmittance of 45%, a solar energy absorption rate of 18%, and
It had a visible light transmittance of 65%.

The water permeability A of the protective film layer is 1.5g/100cm ² /
24hr/10μm/1atm, and finally had the values of d/A=2 and Q×d=30.

This film was sprayed with tap water (containing a small amount of chlorine-based disinfectant) a total of 20 times for 1 minute every 2 hours, and the appearance of "stains" on the transparent insulating film was observed. ” was not observed to occur.

This transparent heat insulating film was attached to the indoor panel surface of the linked window as shown in FIG.

The amount of ventilation in the space (inner window side) is as per pad 12 in the drawing.
It can be changed by changing various packing materials. In addition, the amount of ventilation through the outside window was adjusted by changing the filter 14. This multilayered window was attached to one side of the box, which resembles a building, and the other sides were insulated with styrofoam plates to control the temperature inside the box at 20°C.

The box with this window was placed in a constant temperature room controlled at -10℃, and a heat flow meter sensor was attached to the surface of the window, and the heat transfer coefficient K value (K value (KCal/m ²・hr・℃).The K value was 1.75.On the other hand, for a window with the same structure without a transparent heat insulating film, the K value was 2.65.By using a heat insulating film, ,
It was found that an energy saving effect of 34% was achieved.

Next, this box with a window was placed outdoors with the window facing south. A small heating element (an electric stove) was placed inside the box, and when the temperature inside the box fell below 25°C, the heating element was turned on, and the integrated amount of electricity was calculated. A comparative experiment was conducted using the same box set up in the same manner, except that the transparent heat insulating film was not attached. After conducting an experiment for one week, we determined the ratio of power consumption: with film: without film: 0.71:1.0
It was hot. The average temperature of the outside air was 2°C, and the weather was sunny except for one day during the week of observation. The surface temperature of the glass on the indoor side was approximately 2°C higher at night with the transparent heat insulating film than without the transparent heat insulating film, and 4°C higher during the daytime on clear skies.

Example 2 A 150 Å thick titanium oxide thin film layer was provided on the surface of a 25 μm thick polyethylene terephthalate film, and then a 150 Å thick titanium oxide thin film layer (silver/copper =
90/10) A thin film layer was provided, and a titanium oxide thin film layer with a thickness of 200 Å was further provided. The obtained transparent heat insulating film is hereinafter referred to as transparent heat insulating film-2. Each of these layers was formed by sputtering under conditions of an argon gas atmosphere and a degree of vacuum of 5×10 ^-3 Torr.
A urethane adhesive with a thickness of approximately 0.3 μm was applied to the outer layer (titanium oxide layer) of the transparent heat insulating film-2, and a polypropylene film with a thickness of 13 μm was further laminated. This double-protected transparent heat-insulating film had a solar energy transmittance of 52%, a solar energy absorption rate of 19%, and a visible light transmittance of 71%. The infrared absorption capacity of the protective film including the adhesive layer is 3%.
The water flow rate A was 0.1.

Therefore, Q×d was 39 and d/A was 133.
When this transparent heat insulating film was evaluated for energy saving under the same conditions as in Example 1, the K value of the window with the transparent heat insulating film was 1.80. In this example, an energy saving effect of 32% was obtained.

In a sunny noon test, the electric power ratio of the small stove with transparent insulation film: without transparent insulation film was 0.70:1.0. Note that this protective film had excellent durability.

Example 3 A film containing isodium oxide as a main component was provided on a biaxially stretched polyethylene terephthalate film having a thickness of 75 μm by sputtering.

Sputtering uses an indium oxide sintered target containing 9 mole% tin oxide, introduces a mixed gas with a molar ratio of argon and oxygen of 95:5, maintains the degree of vacuum at 5 × 10 ^-3 Torr, and spreads the substrate. temperature 80
It was carried out under the conditions of ℃. The film thickness of the obtained indium oxide was 2700 Å.

The outermost layer of the thus obtained laminated film (hereinafter referred to as transparent heat insulating film-3)
A 2 μm coating of propylene copolymer was applied, followed by a 1 μm coating of polyacrylonitrile. The obtained transparent heat insulating film had a solar energy absorption rate of 21%, a solar energy transmittance of 64%, and a visible light transmittance of 73%. The infrared absorption capacity Q of the protective film was 6, and the water permeability A was 0.6. Therefore, Q.d was 18 and d/A was 5.

When a transparent heat insulating film with a protective film was attached to a box as in Example 1 and the amount of energy saved was determined, the heat transmission coefficient K value was 1.90, resulting in a heat transfer coefficient of 28
% energy savings were obtained. A comparison of power consumption with film and without film was 0.75:1.0. Furthermore, when we forced a flow of air at a wind speed of 3 m/sec between the outer transparent plate and the inner transparent plate, the K value was the same for windows with and without transparent heat insulating film. It was found that there is no energy saving effect if there is significant ventilation in the window space.

Comparative Example 1 A methacrylate resin was applied as a protective film on the surface of the transparent heat insulating film 1 in Example 1.
It was coated with a thickness of 10 μm.

The heat ray absorption capacity Q of this protective film is 26%, and Q×
d was 260.

Even when a transparent heat insulating film with this protective film was attached to a window, no energy saving effect was observed.

Comparative Example 2 The outermost layer of the transparent heat insulating film 2 in Example 2 was coated with a cellulose triacetate film having a thickness of 2 μm as a protective film. The heat ray absorption capacity of the protective film was 34%, and Q×d was 68. The water permeability A is 6.7 and d/A is equivalent to 0.3. When this transparent heat insulating film was pasted on a window and dew condensed on the surface of the film once every two hours, two speckled "stains" appeared on the surface after 10 days.

It was found that the protective film of the transparent heat insulating film of Comparative Example 2 lacked durability.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a multiplexed window (linked window) of the present invention. FIG. 2 is an enlarged sectional view of a transparent heat insulating film applied to a transparent plate. In the drawing, 16 is a window frame, 20 and 22 are transparent plates, 25 is a space, and 30 is a transparent heat insulating film. Further, 31 is an adhesive or adhesive, 32 is a plastic film, 34 and 38 are high refractive index dielectric thin films, 36 is a metal thin film, and 39 is a protective film.

Claims (1)

[Scope of Claims] 1. A transparent plate serving as an inner window facing the interior of the room, another transparent plate provided through a space from the transparent plate serving as an outer window,
In a multilayer window formed from a window frame holding these transparent plates and a transparent heat insulating film provided in the space; the transparent heat insulating film is made of a plastic film base material and a high refractive index dielectric material provided on the base material. The transparent heat insulating film is made up of a processed layer consisting of a thin film of metal, a thin film of metal, and a protective film, and the transparent heat insulating film is provided so that the plastic film base material is in close contact with the space of the transparent plate that becomes the inner window; The sum of energy transmittance and solar energy absorption rate is 50% or more, and the visible light transmittance is 50% or more; the thickness d (μm) of the protective film is equal to the infrared absorption ability Q
(%) and water permeability A (g/100cm ² /24hr/10μm/
A multilayer window having a transparent heat insulating film, characterized in that it satisfies the following relationship: Q・d≦120 d/A≧1 at 1atm). 2. A multi-layer window having a transparent heat insulating film according to claim 1, which is provided with a transparent heat insulating film having a solar energy absorption rate of at least 10%. 3. A multi-layer window having a transparent heat insulating film according to claim 1, wherein the air flow velocity in the space formed by at least two transparent plates is 0.5 m/sec or less. 4. A multi-layer window having a transparent heat insulating film according to claim 1, wherein the multi-layer window has a linked window structure.