JP3073580U - Glass for freezing / refrigeration and glass articles using the glass - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To improve the heat insulating property of a glass window, to prevent dew condensation from occurring when taking out a product, etc. Provide a used glass article. SOLUTION: The main component is soda-lime glass manufactured by a glass substrate 1 float method. On the surface of the glass substrate 1, a tin oxide film (SnO ₂
2), a silicon oxide film (SiO ₂ film) 3 is formed on the surface of the SnO ₂ film 2 as a permeability increasing layer, and SnO ₂ : F is formed on the surface of the SiO ₂ film 3 as a low radiation layer. Membrane 4
The SnO ₂ film 2 and the SiO ₂ film 3 constitute the intermediate layer 5, and the intermediate layer 5 and the SnO ₂ : F film 4 constitute the laminated film 6.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a glass for freezing / refrigerator and a glass article using the glass, and more particularly, to a glass for freezing / refrigerating used as a glass window that allows the inside state to be seen from the outside while maintaining heat insulation. Also, the present invention relates to a glass article such as a double-glazed glass having improved heat insulating properties as a glass window by using at least one glass.

[0002]

[Prior art]

 Freezers and refrigerators used in stores such as supermarkets and convenience stores are required to have a product display function for displaying products and a product selection function for consumers to freely select products. Glass windows with an opening and closing mechanism that can maintain transparency while maintaining heat insulation are used. In addition, frozen and refrigerated showcases for ice cream and frozen food display, and merchandise inventory, so that product buyers can easily see the product and the store owner can easily enter and exit the product. Similarly to the above, a so-called see-through type vending machine, which allows a consumer to immediately determine the situation, has been proposed a glass window capable of maintaining transparency and maintaining transparency.

[0003] In this type of glass window, there is also known a double glazing in which the heat insulating property of the glass window is improved from the viewpoint of minimizing the energy consumption for maintaining the temperature inside the refrigerator / refrigerator. ing. Examples of such a multi-layer glass include a multi-layer glass in which a plurality of glasses are arranged to face each other and a hollow layer is provided between these glasses, or a plastic film is formed on the glass surface on the side opposite to the plurality of glasses. A laminated glass is known, and a low-emission layer is formed on the glass surface facing the hollow layer, and a double-glazed glass in which the hollow layer is depressurized is also known. There is also known a double-glazing system in which a heat insulating gas such as krypton gas is supplied to a hollow layer to improve heat insulating properties (hereinafter, referred to as “first conventional technology”).

In the first prior art, the surface temperature of the outside glass approaches the outside ambient temperature due to the heat insulating effect of the glass, so that the outside surface of the outside glass is less likely to condense, which impairs the transparency as a glass window. Also, it is possible to prevent the floor from slipping due to dew water flowing down to the outside of the storage.

[0005] In addition, a resin film having a transparent conductive coating acting as a transparent heater on the surface of the outer glass plate on the hollow layer side is adhered to these double-glazed glasses, or A transparent conductive coating is directly applied to the surface of the glass plate, and the transparent conductive coating (transparent heater) is energized and heated to increase the surface temperature of the outer glass plate, thereby condensing the outer surface of the refrigerator further. It is also known to make it difficult (hereinafter, referred to as "second prior art").

Further, as another prior art, a glass window in which a plastic film on which a low-emissivity layer is formed is adhered to the inner surface of a glass plate is known (hereinafter, referred to as “third prior art”). ).

[0007] In the third conventional technique, a heat insulating property is increased and a surface temperature of a glass window inside the refrigerator is increased by sticking a plastic film having a low radiation layer formed on the inner surface of the glass plate. This prevents dew condensation from occurring even when the outside temperature enters the inside of the refrigerator and touches the inner surface of the glass.

[0008]

[Problems to be solved by the invention]

 However, according to the first prior art, while the heat insulating property of the glass window is enhanced, the inside temperature of the inside of the glass window approaches the atmospheric temperature of the inside space. When replenishing products in a refrigerator or refrigerator, the outside atmosphere easily enters the inside of the refrigerator. For this reason, when the outside atmosphere that has entered the inside of the refrigerator contacts the inner surface of the glass window, dew condensation easily occurs, and the visibility of the glass window is hindered for a long time, or dew condensation on the inner surface of the glass window occurs. There was a problem that water could enter the storage and freeze.

In the second prior art, the surface temperature of the outer glass can be increased by applying a current to the transparent conductive coating (transparent heater), which is effective in preventing dew condensation on the outer surface of the refrigerator. However, the transparent conductive coating is conductive and has low emissivity because of its conductivity, so heat can only be transferred to the inside of the refrigerator by heat conduction. Actually, the temperature rise on the surface is extremely low. Moreover, on the one hand, energy is used to energize and heat the transparent conductive coating, and on the other hand, energy is used to cool the inside of the freezer / refrigerator. Was also extremely inefficient.

[0010] Further, in the third conventional technique, a plastic film having a low-emission layer is adhered to the inner surface of the glass window to prevent dew condensation on the inner surface of the glass window as described above. However, since the plastic film generally has a low hardness, for example, in an ice cream showcase or a frozen food display showcase, the plastic film including the low emissivity layer is damaged at the time of cleaning or entering and exiting the product. There is a problem that there is a risk of the occurrence. In other words, the plastic film is easily damaged, so it is necessary to take care not to touch the plastic film when entering and exiting the product, and to take care to wipe it lightly with a soft cloth when cleaning. For this reason, it is practically impossible for the retailer to use the product, and it is virtually impossible to alert the purchaser of the product from touching the inner surface of the glass window. There was a problem that it would be damaged.

In addition, in the third prior art, the plastic film on which the low-emissivity layer is formed is expensive, and requires a lot of work for sticking to the surface of the glass plate, and also secures an aesthetic appearance. For this purpose, there is a problem that a special device for attaching and finishing the plastic film is required.

[0012] The present invention has been made in view of such a problem, and in addition to improving the heat insulating property of the glass window, dew condensation hardly occurs when the product is taken out, etc. In addition, the internal confirmation is improved. It is an object of the present invention to provide an improved glass for freezing / refrigeration and a glass article using the glass.

[0013]

[Means for Solving the Problems]

 The present inventors have conducted intensive studies to achieve the above object, and as a result, formed an oxide semiconductor film on the surface of a glass plate facing the inside of a refrigerator / refrigerator, and the oxide semiconductor film was formed on the glass plate. A middle layer including a first tin oxide film and a silicon oxide film formed in this order on the surface of the substrate, and a low-emission layer including a second tin oxide film formed on the silicon oxide film. In addition to improving the heat insulating properties of the windows, it has been found that dew condensation is less likely to occur on the glass surface when products are taken out, etc., and in addition, the internal confirmation can be improved.

Therefore, the glass for freezing and refrigerator according to the present invention is a glass for freezing and refrigerator that separates the first space at room temperature from the second space at lower temperature than room temperature. An oxide semiconductor film is formed on the surface of the glass plate on the space side, and the oxide film semiconductor film is formed of a first tin oxide film and a film formed on the surface of the glass plate on the second space side in order. It is characterized by comprising an intermediate layer including a silicon oxide film and a low-emission layer including a second tin oxide film formed on the silicon oxide film.

According to the above configuration, the following effects can be obtained.

Since the second tin oxide film acts as a low-radiation layer, the emissivity for radiant heat is reduced between the second space (inside the refrigerator) and the surface of the low-radiation layer, and radiant heat transfer is suppressed. In addition to improving the heat insulating properties of the glass window, the surface temperature of the low-emissivity layer is raised, and the atmosphere in the first space (outside the warehouse) is changed to the second space (outside the warehouse) when taking out or refilling goods from the warehouse. Even when the surface of the low emissive layer is intruded and touches the surface of the low emissive layer, dew condensation is less likely to occur on the surface of the low emissive layer. As the size becomes larger, convective heat transfer is more likely to occur, so that the air on the surface of the lower radiation layer is also easily replaced, and even if dew condensation occurs, it can be eliminated in a short time.

Further, since an intermediate layer made of an inorganic substance including the first tin oxide film and the silicon oxide film is interposed between the low-emission layer and the glass plate, this intermediate layer functions as a refractive index adjusting layer. As a result, the reflection color tone of the refrigerator / refrigerator glass can be easily adjusted to an achromatic color that exhibits a natural color, that is, a neutral color, and is used for a refrigerator / refrigerated showcase or a see-through vending machine. Even in such a case, high transparency can be maintained with a neutral reflection color tone. Since the above-mentioned inorganic substance is composed of a tin oxide film and a silicon oxide film, it does not impair the physical durability of the low-emissivity layer.

Further, since the intermediate layer includes the first tin oxide film and the silicon oxide film, the first tin oxide film acts as an alkali ion release preventing layer, thereby preventing a decrease in low radiation performance. In addition, since the silicon oxide film acts as the permeability increasing layer, the visible light transmittance is increased, and the internal confirmability can be improved.

The low emissivity layer can be easily formed by a chemical vapor deposition (hereinafter, referred to as “CVD”) method in a float glass manufacturing process, is suitable for mass production, and is inexpensive. And a tin oxide film that can be manufactured. Since the tin oxide film is an oxide semiconductor film having excellent physical and chemical durability, the work of cleaning the low-emissivity layer can be easily performed, and the usability is improved at a low cost. In addition, since the characteristics do not deteriorate even when the heat treatment is performed, the heat treatment can be performed after the film formation, thereby simplifying the entire process and performing the heat treatment at a low cost and quickly. it can. The low-emissivity layer can not only be constantly exposed to a low-temperature atmosphere in a refrigerator / refrigerator, but also maintain durability even if a sudden change in temperature occurs due to the intrusion of a room temperature atmosphere outside the refrigerator. When the inside of the freezer / refrigerator is cleaned, it can be prevented from being worn by being rubbed, and the ingress and egress of goods and the careless contact of the purchaser with the low radiation layer can be prevented.

The tin oxide film constituting the low emissivity layer preferably contains fluorine in order to increase the conductivity of the film and improve the heat insulating performance. Hereinafter, the tin oxide film containing fluorine is also referred to as “SnO ₂ : F film”.

[0021] The total thickness of the oxide semiconductor film is preferably from 250 to 750 nm. When the total film thickness is less than 250 nm, the vertical emissivity is increased and the rise of the surface temperature of the low emissive layer is prevented, and when the total film thickness is large, the scratch resistance of the film is improved. If it exceeds, the permeability decreases.

Preferably, the thickness of the first tin oxide film is 10 to 50 nm, the thickness of the silicon oxide film is 10 to 100 nm, and the thickness of the low emissivity layer is 200 to 600 nm. No.

The glass for refrigerators and refrigerators of the present invention has a heat transmission coefficient of 4 to improve heat insulation. It is preferably at most 00 W / m ² · K.

The glass for freezing / refrigerator of the present invention has a visible light transmittance of 75% or more in order to sufficiently confirm the inside of the product inside the freezing / refrigerator from the outside at room temperature. And more preferably 80% or more, and it is necessary to select a glass plate having such visible light transmittance as a material.

Furthermore, the glass for freezing / refrigerator of the present invention minimizes radiation heat exchange between the inside of the freezing / refrigerator and the surface of the low-radiation layer while maintaining high transparency as a glass window, thereby reducing radiant heat. It is necessary to reduce the emissivity, and for that purpose, it is preferable that the vertical emissivity of the oxide semiconductor film be 0.15 or less.

In the glass for freezing / refrigeration of the present invention, the thickness of the glass plate is preferably 2 to 4 mm from the viewpoint of weight reduction and the viewpoint of securing the strength of the glass.

[0027] The freezing / refrigerating glass of the present invention is preferably air-cooled to increase the strength.

[0028] The glass for refrigerators and refrigerators of the present invention may be subjected to a predetermined heat treatment at a predetermined temperature after the low emissivity layer is formed.

Glass for freezing / refrigeration may be subjected to a predetermined heat treatment in order to improve the strength or bend, and heat treatment is necessary even in coating with a substance having hydrophilic / photocatalytic activity or antibacterial treatment. However, when heat treatment is performed after the formation of the low-emissivity layer, the entire process can be performed quickly and at low cost, and the semiconductor oxide film forming the low-emissivity layer is resistant to heat treatment. Therefore, the characteristics do not deteriorate.

Further, in the case of the glass for freezing / refrigeration of the present invention, when a surface layer having a hydrophilicity / water retention function is formed on the surface of the low emissivity layer, the contact angle of water droplets can be reduced. Even if moisture condenses on the surface layer, the dew condensation hardly occurs and the transparency is not hindered.Therefore, from the viewpoint of maintaining high chemical and physical durability, the glass for freezing and refrigerator of the present invention is made of silicon, It is preferable that a surface layer mainly composed of a composite oxide or a mixed oxide containing at least one of aluminum and titanium is formed on the surface of the low-emissivity layer.

The thickness of the surface layer is preferably as low as possible provided that a desired hydrophilicity / water retention function is ensured in order not to impair the low emissivity of the low emissivity layer, ie, the high infrared reflection performance. It is preferably thin, specifically, 0.5 nm to 1000 nm, and most preferably 1 nm to 300 nm.

Further, since the inside of the freezer / refrigerator is often illuminated by lighting equipment such as a fluorescent lamp, it is preferable that the surface layer contains a photocatalytically active substance. As a result, the organic dirt on the glass surface can be decomposed, and the hydrophilic / water retaining function can be maintained for a long period of time.

When the freezer / refrigerator is used for preserving and displaying food, antibacterial treatment is applied to at least one of the inner surface and the outer surface of the refrigerator / fridge from the viewpoint of hygiene. Is preferred. In the case of silver-based treatment, which is often performed as an antibacterial treatment, the antibacterial property is unlikely to occur at low temperatures, and the glass of the present invention, which can maintain a high internal surface temperature of the glass, is suitable for the antibacterial treatment. ing.

The refrigeration / refrigerator glass of the present invention has a greater effect of convective heat transfer when installed in a refrigerator so that the inside of the refrigerator is viewed upward from below, as compared with the case where the glass is installed vertically. The effect is small, but conversely, if the freezer / fridge glass is installed at an angle not more than a predetermined angle with respect to the horizontal direction so that the inside of the refrigerator can be seen from diagonally above or from above, Not only radiative heat transfer but also convective heat transfer is unlikely to occur with the low emissive layer surface, and the surface temperature of the low emissive layer further rises, effectively preventing fogging of the glass plate It becomes possible.

That is, the freezing / refrigerating glass of the present invention has a freezing surface in which the glass surface is horizontal and the inclination angle is 0 to 135 ° with respect to the state in which the low radiation layer is provided on the lower surface in the vertical method. -It is preferable to attach to the refrigerator main body, and desirably, the inclination angle is 0 ° to 60 °.

Further, conventionally, a double-layer glass as a glass article in which an air layer, a heat-insulating gas layer, or a depressurization layer is interposed between a plurality of glass substrates, has a very excellent heat-insulating performance. However, when the above-mentioned glass for refrigerators and refrigerators of the present invention is incorporated into a double-glazed glass, it is necessary to further improve the heat insulation performance while preventing the occurrence of dew condensation. Can be.

In the glass article according to the present invention, a plurality of glasses including one or more of the above-mentioned glasses are disposed so as to face each other such that the low-emitting layer side faces a space in a low-temperature atmosphere lower than room temperature. A hollow layer is formed between the glasses, and the hollow layer is any one of an air layer, a heat-insulating gas layer, and a reduced pressure layer.

When producing a glass article including a reduced pressure layer, it is preferable to perform degassing by heating to 150 ° C. or more so as to maintain the reduced pressure state of the reduced pressure layer for a long period of time. The oxide semiconductor film forming the low-emissivity layer is preferable because characteristics do not deteriorate.

Further, the glass article of the present invention is a transparent film containing a low-emissivity layer or a low-emissivity substance on at least one of the plurality of glasses facing each other, the surface facing the hollow layer. Or a low-emissivity layer or a transparent film containing a low-emissivity substance is disposed in the hollow layer at a distance from the surface of the glass. Thereby, the heat insulating property can be further improved.

In the glass article of the present invention, a plurality of glasses including the above-mentioned glass for freezing / refrigeration are arranged such that the lower radiation layer side faces a space of a low-temperature atmosphere lower than room temperature and a transparent resin layer is interposed therebetween. It is also preferable to form a so-called laminated glass which is superimposed on each other.

Further, it is also preferable to select two pieces of double-glazing from the above-mentioned double-glazing and to overlap the two pieces of double-glazing via a transparent resin layer.

In addition, it is preferable that the above-mentioned double glazing and laminated glass are also subjected to antibacterial treatment from the viewpoint of hygiene, similarly to the above-mentioned freezing / refrigeration glass.

[0043]

[Embodiment of the invention]

 Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a cross-sectional view schematically showing one embodiment (first embodiment) of the glass for freezing / refrigerator according to the present invention.

In FIG. 1, reference numeral 1 denotes a glass substrate mainly composed of soda-lime glass manufactured by a float method, and a tin oxide film (hereinafter, referred to as an alkali elution preventing layer) is formed on the surface of the glass substrate 1. of "SnO ₂ film") 2 is formed, a silicon oxide film as ZoToruso the front surface of the SnO ₂ film 2 (hereinafter, referred to as "SiO ₂ film") 3 is formed, further wherein the SiO ₂ film 3 A SnO ₂ : F film 4 is formed on the surface of the substrate as a low-emission layer. The SnO ₂ film 2 and the SiO ₂ film 3 constitute an intermediate layer 5, and the intermediate layer 5 and the SnO ₂ : F film 4 The laminated film 6 (oxide semiconductor film) is formed. The thickness of the glass substrate 1 is preferably 2 to 4 mm.

In the present embodiment, the surface on which the film is not formed faces the outside (first space) in a room temperature atmosphere, and the surface on which the SnO ₂ : F film 4 is formed is at room temperature. It is installed as a glass window facing the inside of the refrigerator (second space) in a lower temperature atmosphere, such as a supermarket or a convenience store, especially for ice cream and frozen food refrigerators for displaying frozen foods. .

When the above-mentioned glass for freezing / refrigerator is used by being attached to a freezing / refrigerator in a supermarket, a convenience store, or the like, it frequently enters and leaves the product and replenishes the product. It is necessary that the glass substrate 1 has visible light transmittance of 75% or more, more preferably 80% or more. For this purpose, the glass substrate 1 has a composition having a visible light transmittance of 75% or more. Selected and used. In addition, the glass for freezing / refrigeration preferably has a heat transmission coefficient of 4.00 W / m ² · K or less from the viewpoint of improving the heat insulating property. A composition having a heat transmission coefficient of 00 W / m ² · K or less is selected and used.

The thickness of each of the laminated films 6 is adjusted as follows. (1) SnO _2: F film 4 having a thickness of SnO _2: F film 4 is a thin film doped with fluorine (containing) in tin oxide, conductive thin film by doping fluorine in an acid tin As a result, light in the infrared wavelength range (5.5 μm to 50 μm) can be effectively reflected to improve the heat insulation performance. In the heat transfer between the inside of the refrigerator and the refrigerator, there are radiant heat transfer and convective heat transfer. However, the SnO ₂ : F film 4 suppresses the radiant heat transfer by lowering the emissivity to the radiant heat. As a result, the temperature of the glass surface inside the refrigerator rises, thereby preventing the occurrence of dew condensation. The low emissivity can be evaluated by the vertical emissivity (JIS R3106). In order to secure a desired low emissivity, the vertical emissivity is desirably 0.15 or less. In the present embodiment, the thickness of the SnO ₂ : F film 4 needs to be set to 200 nm or more as a range in which such a vertical emissivity can be obtained. On the other hand, the greater the thickness of the SnO ₂ : F film 4, the lower the emissivity can be. However, it is desirable to set the thickness to 600 nm or less, preferably 500 nm or less due to the restrictions on the cost of production equipment.

(2) Thickness of SnO ₂ Film 2 and SiO ₂ Film 3 The refrigerator / refrigerator glass is desirably a neutral type which not only has a high visible light transmittance but also exhibits a natural reflection color tone. . That is, the reflection color tone of an object such as a glass window is quantitatively expressed on a chromaticity diagram by the chromaticness index a ^* , b ^* of the L ^* a ^* b ^* color system specified by the International Commission on Illumination (CIE). (JIS Z8729). To obtain a neutral reflection color tone, the chromaticness indices a ^* and b ^* are | a ^* | ≦ 10, | b ^* | ≦ 10, more preferably | a ^* | ≦ 5, | b ^* | It is preferred that ≦ 5.

However, the adjustment of the reflection color tone is limited only by the SnO ₂ : F film 4, and there is a possibility that a rainbow-colored reflection color may be exhibited due to light interference.

Therefore, in the present embodiment, the intermediate layer 5 having a double structure of the SnO ₂ film 2 and the SiO ₂ film 3 as inorganic substances that does not impair the physical durability of the SnO ₂ : F film 4 is made of glass. The reflection color tone is adjusted so as to be of a neutral type by being interposed between the substrate 1 and the SnO ₂ : F film 4. That is, the glass substrate 1 and SnO _2: When interposing a SnO ₂ film 2 and the SiO ₂ film 3 between the F layer 4, the SnO ₂ film 2 and Si O ₂ film 3 acts as a refractive index adjusting layer, This makes it possible to easily adjust the reflection color tone of the glass for freezing / refrigeration to an achromatic color system exhibiting a natural color tone, that is, a neutral color system.

In the present embodiment, as a range in which such color tone adjustment can be performed, the thickness of the SnO ₂ film 2 is 10 to 50 mm, and the thickness of the SiO ₂ film 3 is 10 to 100 nm. preferable. The total thickness of the laminated film 6 is preferably from 250 to 750 nm. When the total film thickness is 250 or less, the vertical emissivity decreases and contributes to an increase in the surface temperature of the glass. When the total film thickness is large, the scratch resistance of the film is improved. At times, the permeability is below the acceptable range.

In the present embodiment, the intermediate layer 5 has a two-layer structure including the SnO ₂ film 2 and the SiO ₂ film 3, but the intermediate layer 5 is interposed for the purpose of adjusting the color tone as described above. Therefore, the present invention is not limited to the two-layer structure as long as such color tone adjustment is possible, and may be a one-layer structure or a three- or more-layer structure as long as the low radiation performance is not impaired. Alternatively, it may be a gradient composition layer in which a specific film component (for example, Si or Sn) is distributed in a gradient in the film.

In this embodiment, the SnO ₂ : F film 4, which is a low-emission layer, is formed on the surface of the glass substrate 1 facing the inside of the refrigerator. The emissivity for radiant heat is lower between the glass and the inner surface of the glass, radiative heat transfer is suppressed, and convective heat transfer becomes dominant. As a result, not only the heat insulation of the glass window is improved, but also However, when the inside temperature of the glass rises, the outside atmosphere enters the inside of the refrigerator and touches the inside surface of the glass when the product is taken out of the refrigerator or refrigerator or when the product is refilled. Dew condensation is less likely to occur, and even if it occurs, transparency can be restored in a short time.

Moreover, since the SnO ₂ : F film 4 constituting the low-emission layer has excellent physical and chemical durability, it has excellent durability and can be easily cleaned.

Further, in the present embodiment, since the radiant heat transfer is suppressed, the surface temperature of the low radiation layer approaches the surface temperature of the glass plate outside the refrigerator, and the surface temperature of the low radiation layer increases, This also prevents the occurrence of dew condensation, and can prevent loss of transparency.

Further, since the surface temperature of the SnO ₂ : F film 4 rises, the difference between the temperature of the internal space and the surface temperature of the low-radiation layer increases, so that convection heat transfer easily occurs, and therefore the low-radiation layer surface The air is easily exchanged, and even if dew condensation occurs, it can be eliminated in a short time.

Further, in the present embodiment, the rise in the inner surface temperature of the glass is caused by the influence of the ambient temperature outside the glass, so that a heater or the like that requires electric power is not used. It is economical and can contribute to energy saving.

When the glass for freezing / refrigeration of the present invention is used as a glass window for a showcase for ice cream, for displaying frozen foods, etc., the glass itself of the present invention is provided with an opening / closing mechanism to provide the glass. It is also preferable to attach it to the case, and when fitting the main glass to the window frame, provide an opening / closing mechanism such as a so-called pulling mechanism, single pulling mechanism, and opening mechanism on the window frame, and attach the main glass to the showcase so that it can be opened and closed freely. Is also preferred.

FIG. 2 is a view showing an example of a mounting mode when the present freezing / refrigerator glass is mounted on the freezing / refrigerator main body 8. In the figure, the X axis indicates the horizontal direction, and the Y axis indicates the vertical direction. Is shown.

That is, the glass 7 is horizontal, and the low-radiation layer 6 faces the interior at an inclination angle θ with reference to the case where the laminated film 6 on which the low-radiation layer 4 is formed faces downward. Thus, it is attached to the refrigerator / refrigerator body 8.

Further, as shown in FIG. 2A, the inclination angle θ is desirably 135 ° or less even when the glass 7 is attached to the refrigerator / refrigerator body 8 so that the inside of the refrigerator is looked up from outside. Preferably, the angle is 60 ° or less, as shown in FIG. 2 (b). The best mounting mode is as shown in FIG. It is a case where it is attached as follows.

That is, as shown in FIGS. 2B and 2C, when the glass of the present invention is installed in the refrigerator / refrigerator main body 8 in such a manner that it can be seen obliquely from above or from above, the temperature is low. Between the SnO ₂ : F film 4, which is the radiating layer, and the space inside the refrigerator / fridge, not only radiative heat transfer but also convective heat transfer is unlikely to occur, and the surface temperature of the SnO ₂ : F film 4 becomes outside the refrigerator. , The temperature of the SnO ₂ : F film 4 is increased, and the occurrence of dew condensation can be more effectively prevented.

Next, a method for producing the present freezing / refrigerating glass will be described.

As a method for manufacturing the present freezing / refrigerating glass by forming the laminated film 6 on the glass substrate 1, a vacuum deposition method, a sputtering method, a coating method, or the like is possible. It is most preferable to use a CVD method which can easily form a film, is suitable for mass production, and is inexpensive in terms of cost.

FIG. 3 is a schematic configuration diagram schematically showing a CVD film forming apparatus. The CVD film forming apparatus is provided with a heater 9 for heating the glass substrate 1 to a predetermined temperature, and is conveyed in the direction of arrow A. A plurality of film-forming material supply units 10 (in the present embodiment, first to fifth film-forming material supply units 10a to 10e) are arranged so as to cover the width direction of the incoming glass substrate 1. .

In the CVD film forming apparatus, the glass substrate 1 cut into a predetermined shape is heated to a predetermined high temperature by a heater 9 and conveyed on a mesh belt. Is supplied to the surface of the glass substrate 1, the film forming material is thermally decomposed on the glass substrate 1 through the thermal energy of the glass substrate 1, and a desired thin film is deposited on the glass substrate 1. For example, when the laminated film 6 as shown in FIG. 1 is manufactured, a mixed gas comprising a tin compound, oxygen, water vapor, and nitrogen is supplied from the first film forming material supply unit 10a to the glass substrate 1. The SnO ₂ film 2 is formed as a first layer by being supplied to the surface, and a silicon compound, oxygen, and nitrogen are supplied onto the glass substrate 1 from a second film forming material supply unit 10b to form a second layer. The SiO ₂ film 3 is formed. Further, a mixed gas comprising a tin compound, oxygen, water vapor, nitrogen and a fluorine compound is supplied from the third film forming material supply unit 10c and, if necessary, the fourth and fifth film forming material supply units 10d and 10e. The SnO ₂ : F film 4 is supplied on the glass substrate 1 to form a third layer. That is, when a thick film is formed, as described above, the same film forming material is supplied to a plurality of stages (for example, three stages of the third to fifth film forming material supply units 10c to 10e) as described above. ) And supplied onto the glass substrate 1.

The tin raw material for forming the SnO ₂ film 2 includes monobutyltin trichloride, tin tetrachloride, dimethyltin dichloride, dibutyltin dichloride, dioctyltin dichloride, tetramethyltin, tetrabutyltin, tetrabutyltin Tin compounds such as laoctyl tin can be used, and oxygen, steam, dry air, etc. can be used as the oxidizing material.

Further, as a silicon raw material when forming the SiO ₂ film 3, monosilane, disilane, trisilane, monochlorosilane, dichlorosilane, 1,2-dimethylsilane, 1,1,2-trimethyldisilane, 1 Silane compounds such as 1,1,2,2-tetramethyldisilane, tetramethylorthosilicate, tetraethylorthosilicate, and the like can be used. Oxidation materials such as oxygen, steam, dry air, carbon dioxide, Carbon oxide, nitrogen dioxide, ozone and the like can be used.

Further, as the fluorine compound for forming the SnO ₂ : F film 4, trifluoroacetate, hydrogen fluoride, bromotrifluoromethane, chlorodifluoromethane, difluoroethane and the like can be used.

As described above, the freezing and refrigerator glass of the present invention can be easily formed into a film during the float glass manufacturing process, and can be mass-produced at low cost.

Further, the SnO ₂ : F film 4 is hardly deteriorated by heat treatment, and a strengthening process, a bending process, a degassing process and the like can be performed after the formation of the SnO ₂ : F film 4. Can be simplified, and can be performed quickly and at low cost.

[0073] For example, in order to improve the strength of glass by air cooling tempering through heat tempering furnace or the like, SnO a low emissivity layer _2: SnO ₂ by heat treatment after the formation of the F film 4: Characteristics of the F film 4 It can be performed quickly and at low cost without causing deterioration.

That is, the tempered glass is generally obtained by using a heat strengthening furnace having a heater section and an air cooling section. In such a case, first, the glass on which the SnO ₂ : F film 4 is formed is firstly heated. After heating to 600 ° C. or higher in the air-cooling section, the air-cooling section discharges compressed air at normal temperature from the compressor and supplies the compressed air to the glass surface, whereby the glass surface is heated. Upon cooling, a compressive stress is generated, and the air cooling is strengthened. As a result, tempered glass having a surface compressive stress of 60 MN / m ² or more and a crushing number of 40 or more specified in JIS R3206 can be quickly obtained at low cost.

Further, by adjusting the air cooling rate of the glass by the same method, it is also possible to obtain a double strength glass having a surface compressive stress of 20 to 60 MN / m ² specified by JIS R3222.

[0076] Similarly, when performing the bending process, SnO _2: By performing the heat treatment at 600 ° C. or higher after the formation of the F layer 4, SnO _2: degrading the properties of a low emissivity layer of F film 4 A curved glass can be obtained by performing a bending process without the need.

Also, when degassing is performed at the time of producing a double glazing having a hollow layer as a decompression layer, the SnO ₂ : F film 4 is formed, and then a heat treatment is performed at 150 ° C. or more, so that the SnO ₂ : F ₂ : A desired degassing process can be performed without deteriorating the characteristics of the F film 4 as a low radiation layer.

In addition, refrigerators and refrigerators in supermarkets, convenience stores, and the like are generally used for storage and display of foods. In order to prevent the propagation of pathogenic bacteria such as Escherichia coli and O157 from the viewpoint of hygiene, silver colloids It is preferable to apply an antimicrobial agent such as a dispersion to the surface of the glass substrate 1 and the surface of the SnO ₂ : F film 4 to perform an antimicrobial treatment. However, and in this case, SnO _2: For antimicrobial treatment on the F layer 4 is the SnO _2: so as not to impair the low radiation function of chromatic of F film 4 is required to apply the antibacterial treatment.

Next, FIG. 4 is a cross-sectional view schematically showing a second embodiment of the glass for freezing / refrigerator according to the present invention. In the second embodiment, FIG. As in the embodiment, SnO is formed on the surface of the glass substrate 1._TwoFilm 2, SiO_TwoFilm 3 and SnO_Two: F film 4 is sequentially formed and the SnO_Two: TiO which is a photocatalytic active layer is formed on the surface of the F film 4._TwoA film 11 is formed and the TiO_TwoThe surface of the film 11 is made of SiO containing aluminum (Al)._TwoFilm (hereinafter referred to as “SiO_Two: Al film) is formed. _Two Film 11 and SiO_Two: A surface layer 13 is formed with the Al film 12, and the surface layer 13 has a hydrophilic / water retaining function.

That is, when the surface layer 13 having a hydrophilicity / water retention function is formed on the surface of the SnO ₂ : F film 4 which is a low-emission layer, even when water droplets adhere to the surface layer 13, the contact angle is reduced. Therefore, even if moisture condenses on the surface layer 13, dew condensation is unlikely to occur, so that it is possible to prevent the visibility from being impaired. Moreover, in the second embodiment, since the surface layer 13 having the hydrophilic / water retaining function includes the TiO ₂ film 11 which is the photocatalytic active layer, the interior of the freezing / freezer is a lighting device such as a fluorescent lamp. It can decompose organic dirt on the surface of the refrigerator / refrigerator glass even if it is illuminated by the water, and maintain the hydrophilicity / water retention function for a long time.

The surface layer 13 needs to be formed so as not to impair the high-infrared reflection performance of the low-emissivity layer. For this purpose, it is necessary to consider the balance between the hydrophilicity / water retention function and the low-emission performance. It is desirable to be as thin as possible, and the total thickness of the surface layer 13 is 0.5 to 1000 nm or less, preferably 0.5 to 700 nm or less, more preferably 1 to 500 nm or less, and still more preferably 1 to 300 nm or less. It is preferred that

The surface layer 13 can be manufactured by a vacuum evaporation method, a sputtering method, a CVD method, a coating method, or the like. However, in order to activate the photocatalytic substance, heat treatment is performed during or after film formation. It is effective to apply.

Next, a case where the surface layer 13 is manufactured by the sputtering method will be described.

FIG. 5 shows a load-lock type in-line type magnetron sputtering apparatus (hereinafter, referred to as a “sputtering apparatus”) for forming a surface layer 13 on the surface of the SnO ₂ : F film 4. It has a load lock chamber 15 and a film forming chamber 16, and the film forming chamber 16 is provided with first and second cathodes 17 and 18 and a heater 19.

For example, in the case of forming the surface layer 13 as shown in FIG. 4, the glass 7 having the laminated film 6 formed on the surface thereof in the first embodiment is transported to the load lock chamber 15. After being evacuated and evacuated to a predetermined pressure, it is transferred to the film forming chamber 16 as shown by arrow B. Then, a sputtering gas is supplied from a gas supply port 20 to the film forming chamber 16 and the glass 7 is heated to a predetermined temperature, and a predetermined voltage is applied to the first cathode 17 on which titanium as a target material is set. This causes reactive sputtering with oxygen at a predetermined high temperature, and the glass 7 reciprocates under the first cathode 17 so that TiO ₂ as a fourth layer is formed on the surface of the laminated film 6. A film 11 is formed. Further, silicon to which Al is added is set as a target on the second cathode 18, and the glass 7 is transported in the direction of arrow C after the TiO ₂ film 11 is formed. A reciprocating motion is made below 18, and a SiO ₂ : Al film 12 as a fifth layer is formed on the surface of the TiO ₂ film 11 by reactive sputtering, thereby producing a refrigerator / refrigerator glass having the surface layer 13. be able to. The thickness of the surface layer 13 is controlled by adjusting the number of reciprocations and the moving speed of the glass 7.

FIG. 6 is a cross-sectional view of a principal part showing a first embodiment of a double glazing as a glass article using the above-mentioned glass for freezing / refrigerator. The frozen glass 7 for refrigerator and refrigerator and the float glass 27 as a single glass plate made of soda-lime glass or the like are arranged so that the laminated film 6 is exposed to the outside air, and a desiccant is provided near both ends thereof. Are interposed, and both ends are heat-sealed and sealed by a sealing material 22 such as butyl rubber. Thus, the hollow layer 23 is defined by being surrounded by the freezing / refrigerating glass 7, the float plate glass 27, the spacer member 21, and the sealing material 22.

It is said that this type of double glazing can improve the heat insulating performance even more than a single glass plate. Therefore, the use of the freezing / refrigerating glass 7 of the present invention is considered. Accordingly, it is possible to prevent the occurrence of dew condensation and to further improve the heat insulating performance. The hollow layer 23 is preferably an air layer or an insulating gas layer filled with argon gas or the like from the viewpoint of enhancing the heat insulating performance, and the hollow layer 23 is in a dry state from the viewpoint of preventing dew condensation. Is preferred. In order to keep the hollow layer 23 in a dry state and a clean state, it is preferable that both ends are completely sealed with the sealing material 22 as described above, but the sealing state is incomplete. Even if a device for replacing the gas in the hollow layer 23 is provided, it is sufficient that the heat insulating property and the transparency of the double-glazed glass are not adversely affected.

Further, from the viewpoint of ensuring the desired heat insulating performance of the hollow layer 23, it is preferable that the interval t between the freezing / refrigerating glass 7 and the float plate glass 27 is set to 4 mm or more.

FIG. 7 is a cross-sectional view of a principal part showing a second embodiment of a double glazing. The double glazing is obtained by applying a low-emission coating to the glass substrate 1 in contact with the hollow layer 23, The low emissive layer 24 is formed by attaching a transparent film containing a radioactive substance, and the heat insulating property is further improved.

FIG. 8 is a cross-sectional view of a principal part showing a third embodiment of a double-layer glass. The double-layer glass is configured such that the laminated film 6 is exposed to the outside air and the hollow layer 23 has a distance t. Is set to 0.2 mm to 1 mm, and a predetermined reduced pressure state is set. Further, both ends are sealed with low melting point glass 25, and the freezing / refrigerating glass 7 and the flat plate glass A minute spacer member 26 for adjusting the distance from the space 27 is provided.

[0091] By configuring the hollow layer 23 with a reduced pressure layer in this manner, the same operation and effect as described above can be achieved.

Note that the present invention is not limited to the above embodiment, and can be similarly applied to so-called laminated glass. That is, a plurality of glasses including one or more glasses for freezing / refrigerating glass face each other via a transparent resin such as polyvinyl butyral such that the low radiation layer side faces the space of a low-temperature atmosphere lower than room temperature. It is also preferable that the glass is adhered to improve safety when the glass is broken.

In addition, the present invention provides a double-layer glass having two or more hollow layers, or a transparent film in a hollow layer separated from a glass surface facing each other (including a case where a low-emission substance is contained). It is also preferable that the present invention is applied to a glass article in which a double-glazed glass and a laminated glass are combined.

In the above embodiment, a planar glass plate has been described, but the present invention can be similarly applied to a curved glass plate.

[0095]

【Example】

 Next, embodiments of the present invention will be specifically described.

The present inventor washed and dried a float plate glass having a thickness of 3 mm, and laminated the float plate glass on the glass substrate 1 using a CVD film forming apparatus (see FIG. 3). Film 6 was formed. That is, the glass substrate 1 is conveyed by an open-to-atmosphere type mesh belt, the surface temperature of the glass substrate 1 is heated to about 650 ° C. by the heater 9, and then the glass substrate 1 passes below the film forming material supply unit 10. In the meantime, a predetermined film forming material is supplied from the film forming material supply unit 10 onto the glass substrate 1, and a chemical reaction is caused on the glass substrate 1 to precipitate a solid phase, and the SnO ₂ film 2, the SiO ₂ film 3, and SnO _2: F film 4 are sequentially stacked on a glass substrate 1, thereby the film structure is a glass substrate 1 / Sn O ₂ film 2 / SiO ₂ film 3 / SnO _2: F film 4 (see FIG. 1) (Examples 1 to 4) were prepared.

[0097] Specifically, using monobutyltin trichloride (hereinafter referred to as "MBTC") as a tin raw material, heating the MBTC to 150 ° C to reduce the vapor of the MBTC to 0.001 per mole of nitrogen. Nitrogen is transported as a carrier gas at a molar concentration and supplied to the first film forming material supply unit 10a, and oxygen as a gas oxide is supplied to the first film forming material supply unit 10a from another system. A thermal decomposition reaction and an oxidation reaction were caused on the glass substrate 1, and a SnO ₂ film 2 having a thickness of 25 nm was laminated on the glass substrate 1 to form a first layer. Next, monosilane is used as a silicon raw material, a monosilane gas is directly supplied from a cylinder to the second film forming raw material supply section 10b, and oxygen as an oxidizing gas is formed from another system as in the case of forming the SnO ₂ film 2 described above. is supplied to the film raw material supply unit 10b, by causing thermal decomposition reaction and oxidation reaction on SnO ₂ film 2 by laminating a SiO ₂ film 3 having a thickness of 25nm on the SnO ₂ film 2, to form a second layer . Then, MTBC as tin raw material, using the trifluoroacetate as a fluorine raw material, SiO third to fifth to inject deposition material from the deposition material supplying section 10c~10e of thickness 350nm on the SiO ₂ film 3 ₂ : F film 4 was laminated to form a third layer. That is, since the film thickness of the SiO ₂ : F film 4 is as thick as 350 nm, the supply of the film forming raw material onto the SiO ₂ film 3 was performed in multiple stages. Specifically, the MBTC is heated to about 150 ° C. to transport the MBTC vapor at a concentration of 0.01 mol per mol of nitrogen with nitrogen as a carrier gas. Nitrogen was transported as a carrier gas at a concentration of 5 moles per mole, and trifluoroacetate was heated to about 150 ° C., and the vapor of the trifluoroacetate was transported from another system using nitrogen as a carrier gas, and MTBC was removed. Vapor, water vapor and trifluoroacetate vapor are supplied to the third to fifth film-forming raw material supply units 10c to 10e, and the third to fifth film-forming raw material supply units 10c to 10e are oxidized. Oxygen as gas was supplied from another system. Then, vapors of these MTBC vapor trifluoroacetate, water vapor, oxygen is supplied onto the SiO ₂ film 3 cause thermal decomposition reaction and oxidation reaction, SiO ₂ on the SiO ₂ film 3: F film 4 Lamination was performed to form a third layer (Example 1).

Next, the inventors of the present invention used freezing / refrigerating glasses having different thicknesses of the SnO ₂ film 2, the SiO ₂ film 3, and the SiO ₂ : F film 4 in Examples 2 to 4 of the present invention and It was produced as Comparative Examples 1 and 2. They are shown in Table 1.

[0099]

[Table 1]

Next, the present inventors set the test pieces (Examples 1 to 4 and Comparative Examples 1 and 2) to have the SnO ₂ : F film 4 facing the inside of the refrigerator as a glass window of a vertical door which can be freely opened and closed. At the inside temperature of -20 ° C and outside temperature of 20 ° C, the surface temperature of the SnO ₂ : F film 4 side (hereinafter referred to as “inside surface temperature”) and the glass substrate 1 side. The surface temperature (hereinafter, referred to as “outside-chamber surface temperature”) was measured, and the heat transmission coefficient as a measure of the heat insulation performance was measured in accordance with JIS A4710. However, natural convection was used for both the inside of the heating box on the constant temperature room side and the low temperature room side without using an airflow stirrer.

Further, the inventor of the present invention sets Comparative Example 3 in which the float plate glass alone was attached to the refrigerator, and further provided the freezer with the SnO ₂ : F film 4 facing the outside of the refrigerator for the test piece of Example 1. In the same manner as described above, the inside temperature, the outside surface temperature, and the heat transmission coefficient were measured at a temperature of −20 ° C. and an external temperature of 20 ° C.

The surface temperature was measured by using the infrared radiation temperature corrected by the emissivity of the glass surface and the low radiation layer. The heat transmission coefficient was 5 m / sec for the external wind speed, 20 ° C. for the external air temperature, and Inner wind speed Measured under the conditions of natural convection and an internal temperature of 0 ° C.

Further, since the glass for freezing / refrigeration is required to have excellent transparency, the visible light transmittance is measured in accordance with JIS R3106. The emissivity was measured according to JIS R3106.

Table 1 shows the measurement results of Examples 1 to 4 and Comparative Examples 1 to 4.

In Table 1, in Comparative Example 1, since the thickness of the SnO ₂ : F film 4 of the third layer is less than 200 nm and the thickness of the laminated film 6 is less than 250 nm, visible light Although the transmittance was 83.4% and the internal confirmation was good, the surface temperature inside the refrigerator was 1.80 ° C, the surface temperature outside the refrigerator was 2.30 ° C, and surface dew condensation occurred. Was as high as 4.6 W / m ² · K, and the heat insulation was poor.

In Comparative Example 2, since the thickness of the third layer SnO ₂ : F film 4 exceeds 750 nm and the thickness of the multilayer film 6 exceeds 600 nm, the heat transmission coefficient is 3.68 W / m ^2. -Low K and good heat insulation. The inside surface temperature of the refrigerator was 3.80 ° C and the outside surface temperature of the product was 4.30 ° C. No surface condensation occurred, but the visible light transmittance was 74.5. %, The internal confirmation was poor.

In Comparative Example 3, since the float plate glass alone was used, the visible light transmittance was 90.1%, and the internal confirmability was good. However, the inside surface temperature of the refrigerator was 0.50 ° C., and the outside surface temperature of the refrigerator was 0.50 ° C. However, since the surface dew condensation was as low as 1.10 ° C. and no low-emission layer was formed, the heat transmission coefficient was as high as 4.60 (W / m ² · K), and the heat insulating property was poor.

Further, in Comparative Example 4, since a low radiation layer (SiO ₂ : F film 4) was formed, the heat transmission coefficient was as low as 3.60 W / m ² · K and the heat insulating property was good. And the inside surface temperature was -3.20 ° C and the outside surface temperature was -2.70 ° C, and surface dew condensation occurred.

On the other hand, in Examples 1 to 4, the first layer of the SnO ₂ film 2 has a thickness of 10 to 50 nm, the second layer of the SiO ₂ film has a thickness of 10 to 100 nm, and the third layer has a thickness of 10 to 100 nm. Since the thickness of the SnO ₂ : F film 4 is 200 to 600 nm and the layer thickness of the laminated film 6 is 250 to 750 nm, the internal surface temperature of the chamber is 3.20 to 3.82 ° C. The outside surface temperature is 4.10 ° C to 4.30 ° C and the surface temperature inside and outside the room is high and no surface condensation occurs, and it is possible to prevent clouding or dew condensation on the window glass. However, it was confirmed that visibility from the outside to the refrigerator / refrigerator can be prevented from being impaired. Moreover, the heat transmission coefficient was 3.68 to 3.78 W / m ² · K, and the desired heat insulating performance was able to be secured.

Further, in Examples 1 to 4, the visible light transmittance was 75% or more, sufficient transparency could be secured, and the vertical emissivity was 0.15 or less. It can be seen that the radiant heat exchange between them is suppressed and the emissivity for radiant heat is reduced, contributing to the rise in surface temperature.

Since it is preferable that the reflection color tone is of a neutral type, the reflectance spectrum from the thin film surface side of Example 1 was measured in accordance with JIS R3106, and in accordance with JIS Z8729. The chromaticity indices a ^* and b ^* were calculated, and the reflection color tone was evaluated. As a result, the chromaticness indices a ^* and b ^* are “−1.5” and “−1.0”, respectively, and are therefore in the range of | a ^* | ≦ 5, | b ^* | ≦ 5, and are neutral. It was confirmed to have a system reflection color tone.

As is clear from Table 1, in Examples 1 to 4, the thicker the SiO ₂ : F film 4 is, the lower the emissivity to radiant heat is. It was found to be effective in prevention.

Second Embodiment Next, the inventors of the present invention performed a heat treatment using a test piece having the same film configuration as that of the above-described first embodiment to produce a reinforced glass.

Specifically, in order to enhance the convection heating, the test piece is heated at a heating temperature of 640 ° C. by adjusting the upper inflow air amount in a heater portion of the heat strengthening furnace, and then is heated from a compressor to a normal temperature in a wind cooling portion. Compressed air was supplied to the test piece to produce a tempered glass having a surface compressive stress of 80 MN / m ² and having no apparent distortion.

In addition, JIS R3206 does not specify a tempered glass for a glass plate having a thickness of 3 mm. However, in the present embodiment, the number of shatters is 40 or more according to the method specified in JIS R3206, Was determined.

Then, the visible light transmittance and the vertical emissivity of the tempered glass were measured to be 83% and 0.13, respectively, and there was no change before and after the heat treatment.

That is, it was confirmed that the glass for freezing / refrigeration of the present invention can obtain a tempered glass which is not impaired in terms of performance even when subjected to heat treatment, and is therefore excellent in heat insulation performance and does not impair transparency. Was done.

The same measuring instrument as that used in the first embodiment was used for calculating the visible light transmittance and the vertical emissivity.

Third Embodiment Next, the present inventors performed an antibacterial treatment using a test piece having the same film configuration as that of the first embodiment described above.

That is, the test piece was heated to about 300 ° C., and a dispersion of silver colloid (concentration: 0.1%) was sprayed on both sides of the test piece to perform antibacterial treatment.

Then, with respect to the test piece of the third embodiment subjected to the antibacterial treatment as described above, the film adhesion method of the antibacterial force test method I (1998 version) proposed by the Antibacterial Product Technology Council was When the film was changed to 0.1 ml with no film for glass, the antimicrobial properties were observed on both sides of the test piece.

The visible light transmittance and the vertical emissivity of the test piece of the third example were measured to be 83% and 0.13, respectively, and the chromaticness index of the reflection color tone was measured. a ^* and b ^* were "-1.5" and "-1.0", respectively, and there was no change before and after the antibacterial treatment.

The same measuring device as in the first embodiment was used for measuring the visible light transmittance, the vertical emissivity, and the reflection color tone.

Next, the inventors of the present invention attached the test piece of the third embodiment to a freezer with the SiO ₂ : F film 4 facing the inside of the refrigerator as a glass window of a vertical door which can be opened and closed. When the inside surface temperature, outside surface temperature, and heat transmission coefficient were measured at a temperature of -5 ° C and an outside temperature of 20 ° C, they were 10.1 ° C, 10.4 ° C, and 3.4 (W / m, respectively). ²・ K), which indicates that it has sufficient heat insulation performance and can prevent the occurrence of dew condensation inside and outside the refrigerator which deteriorates the transparency.

The measurement of the inner surface temperature, the outer surface temperature, and the heat transmission coefficient was performed using the same measuring apparatus as in the first embodiment.

Fourth Embodiment Next, as shown in FIG. 2B, the present inventors raise and lower the refrigerator / refrigerator body 8 at an angle of 20 ° (= θ 2) with respect to the horizontal direction. Glass and float plate glass of the present invention were attached as door glass, and the transparency was confirmed.

That is, a test piece having the same film configuration as in Example 1 was used for one glass of the door glass, and a float glass alone was used for the other glass, and the test piece was made of SiO ₂ : The F membrane 4 was attached to the freezer / refrigerator body 8 so as to face the inside of the refrigerator.

When the inside temperature was set to −30 ° C. and the outside atmosphere temperature was set to 20 ° C., the product was put into the inside of the refrigerator and an opening / closing door opening / closing test was performed. In contrast, the test piece of the present invention showed only a slight fogging, which did not affect the visibility, and thus impaired the transparency. Not confirmed.

[Fifth Embodiment] Next, the present inventors stacked a surface layer 13 on the surface of a test piece having the same film configuration as that of the first embodiment by using a sputtering apparatus (see FIG. 5). Specimen of glass substrate 1 / SnO ₂ film 2 / SiO ₂ film 3 / SnO ₂ : F film 4 / TiO ₂ film 11 / SiO ₂ : Al film 12 (see FIG. 4) (Example 11) Was prepared.

That is, the glass 7 having the same film configuration as in Example 1 was washed, evacuated to a predetermined pressure in the load lock chamber 15, and then transferred to the film formation chamber 16 as shown by the arrow B. Then, oxygen is supplied from the gas supply port 20 so that the pressure in the film forming chamber 16 becomes 0.3 Pa, the glass 7 is heated to about 350 ° C. by the heater 19, and then titanium as a target substance is set. A DC voltage of 440 V is applied to the first cathode 17, which causes reactive sputtering with oxygen, and the glass 7 reciprocates under the first cathode 17, whereby the SnO ₂ : F film 4 A TiO ₂ film 11 having a thickness of 250 nm was laminated on the surface to form a fourth layer. Next, after turning off the power of the heater 19, the same reactive sputtering as described above was caused by using the second cathode 18 set with silicon to which 10 wt% of Al was added as a target, and the test piece was removed. By reciprocating below the second cathode 18, the SiO ₂ : Al film 12 having a film thickness of 10 nm was laminated to form a fifth layer (Example 11).

The obtained glass was measured for the vertical emissivity in the same manner as in the first example, and was further subjected to a measurement of a contact angle of a water drop and a photocatalytic activity test.

As a result, the vertical emissivity was 0.13 as in the case of Example 1, and therefore, no performance deterioration due to the formation of the surface layer 13 was observed. In addition, it was confirmed that the contact angle of water droplet can be as small as 5 °. Further, the photocatalytic activity test was carried out by applying triolein to the surface of the surface layer 13 and irradiating it with ultraviolet rays, and good results were obtained.

Next, the inventors of the present invention confirmed the transparency when the present test piece (Example 11) was used as a glass window of a double door installed in a vertical direction of a freezer.

That is, the test piece of Example 11 was used for one glass window of the double door glass, and the float glass sheet alone as a comparative example was used for the other glass window (Comparative Example 11). The piece was attached to the freezer body with the surface layer 13 facing the inside of the refrigerator.

The temperature inside the refrigerator is set to −20 ° C., the ambient temperature outside the refrigerator is set to 20 ° C., the inside of the refrigerator is turned on from 9 to 20 o'clock, and the door is regularly opened and closed for 30 days. A door open / close test was thus conducted.

Table 2 shows the measurement results of Example 11 and Comparative Example 11.

[0137]

[Table 2]

As is clear from Table 2, the opening / closing of the door fogged the float plate glass alone and lowered the transparency, and the result of the opening / closing test was poor. Medium (30 days), no fogging occurred, and good results were obtained.

As a result, it was confirmed that even if the inside of the freezer / refrigerator was illuminated with a fluorescent lamp or the like, organic dirt on the surface could be decomposed and the hydrophilicity / water retention function could be maintained for a long period of time.

Sixth Example Next, the present inventor produced three different types of double-glazed glass (Examples 21 to 23) using the test piece of Example 1.

That is, as shown in FIG. 6 above, a float plate glass made of the test piece of the present invention, the freezing / refrigerating glass (hereinafter referred to as “the present invention glass”) 7 and the soda-lime glass, which are the test pieces of the first embodiment. 27, the glass 7 of the present invention and the float glass 27 are arranged so as to face each other such that the surface on which the laminated film 6 of the test piece is formed is located outside, and the hollow glass 23 is filled with air. Produced. The interval t between the hollow layers 23 was adjusted to 12 mm by the spacer member 21 made of aluminum (Example 21).

Next, similarly to the above, using the glass 7 of the present invention and the float plate glass 27, a double glazing in which the hollow layer 23 was filled with argon gas as a heat insulating gas was produced. The introduction of argon gas was carried out by penetrating two holes in the aluminum spacer member 21 and supplying argon gas to the hollow layer 23 from one of the holes by means of a cylinder. The gas inside the hollow layer 23 was replaced with argon gas by sealing the two holes with a sealing material. The interval t between the hollow layers 23 was adjusted to 6 mm by the spacer member 21 (Example 22).

Next, as shown in FIG. 8, the glass 7 of the present invention and the float glass 27 are used, and the glass 7 of the present invention is placed so that the surface of the test piece on which the laminated film 6 is formed is located outside. The float glass plate 27 is arranged to face the same, and the minute spacer member 26 made of metal is sandwiched between the glass 7 of the present invention and the float glass plate 27 to adjust the interval t between the hollow layers 23 to 0.2 mm. Both upper and lower ends were sealed with a melting point glass 25. That is, a small hole is provided in the float glass sheet 27, and the glass sheet 7 and the float glass sheet 27 are heated to about 350 ° C. to fuse the low-melting glass 25 to about 250 ° C. After the layer 23 was put in a reduced pressure state, the layer 23 was sealed off, and the hollow layer 23 was used as a reduced pressure layer. The pressure in the reduced pressure layer was 1 Pa or less (Example 23).

Next, after measuring the visible light transmittance of the test piece of each of the above embodiments, the present inventors set the present invention glass 7 inside the refrigerator as a glass window of a vertical door which can be freely opened and closed. It was attached to the freezer and the inside temperature was -20 ° C, the outside temperature was 20 ° C, and the inside surface temperature, outside surface temperature, and heat transfer coefficient were measured.

Further, in the same manner as described above, a comparative example in which the hollow layer 23 was used as an air layer, an argon gas layer, and a reduced pressure layer using two float plate glasses (Comparative Examples 21 to 23) was prepared. In the same manner as in the above, it was attached to a freezer as a glass window of a vertical door, and the same measurement as in Examples 21 to 23 was performed. The measurement was performed using the same device as in the first embodiment.

Table 3 shows the measurement results of the respective examples and comparative examples.

[0147]

[Table 3]

As is clear from Table 3, Comparative Examples 21 to 23 have a visible light transmittance of 80% or more and a heat transmission coefficient of 2.5 (W / m ² · K) or less. Although it has excellent heat insulation performance, it does not have a low radiation layer, so the surface temperature inside and outside the refrigerator is low, fogging and dew condensation are likely to occur on the glass, and transparency is impaired.

On the other hand, in Examples 21 to 23, the low emissive layer was formed, so that the heat insulation performance was excellent and the surface temperatures inside and outside the refrigerator were high as compared with Comparative Examples 21 to 23. However, it was confirmed that the loss of visibility could be avoided as much as possible.

[0150]

[Effect of the invention]

 As described in detail above, according to the glass for refrigerators and refrigerators of the present invention, the second tin oxide film acts as a low-emissivity layer, so that the second space (inside the refrigerator) and the low-emission layer can be used. The emissivity of radiant heat to the surface is reduced, radiant heat transfer is suppressed, and not only the heat insulation of the glass window is improved, but also the surface temperature of the low radiant layer is raised, so that products can be taken out of the warehouse or products can be removed. Even when the first space (outside the refrigerator) atmosphere enters the second space (inside of the refrigerator) and touches the surface of the low emissivity layer at the time of replenishment, dew condensation hardly occurs on the surface of the low emissivity layer. As a result, the difference between the temperature in the second space and the surface temperature of the low-radiation layer increases, so that convective heat transfer easily occurs. Therefore, the air on the low-radiation layer surface is also easily exchanged. It can be resolved in time.

[0151] Further, since an intermediate layer made of an inorganic material including the first tin oxide film and the silicon oxide film is interposed between the low emission layer and the glass plate, this intermediate layer functions as a refractive index adjusting layer. As a result, the reflection color tone of the refrigerator / refrigerator glass can be easily adjusted to an achromatic color that exhibits a natural color, that is, a neutral color. Even in such a case, high transparency can be maintained with a neutral reflection color tone. Since the above-mentioned inorganic substance is composed of a tin oxide film and a silicon oxide film, it does not impair the physical durability of the low-emissivity layer.

Further, since the intermediate layer includes the first tin oxide film and the silicon oxide film, the first tin oxide film acts as an alkali ion release preventing layer, thereby preventing a decrease in low radiation performance. In addition, since the silicon oxide film acts as the permeability increasing layer, the visible light transmittance is increased, and the internal confirmability can be improved.

The low emissivity layer includes a tin oxide film. Since the tin oxide film is an oxide semiconductor film having excellent physical and chemical durability, the low emissivity layer can be easily cleaned. It is possible to improve the usability at a low cost, and since the characteristics do not deteriorate even if the heat treatment is performed, the heat treatment can be performed after the film formation. Heat treatment can be performed quickly at a low cost with simplification. The durability can be maintained even if the low-emission layer is constantly exposed to the low-temperature atmosphere in the freezer / refrigerator, even if a sudden change in temperature occurs due to the intrusion of the room temperature atmosphere outside the refrigerator. When the inside of the freezer / refrigerator is cleaned, it can be prevented from being rubbed and worn, and the ingress and egress of goods and the careless contact of the purchaser with the low radiation layer can be prevented.

[0154] Since the tin oxide film constituting the low-emissivity layer contains fluorine, the conductivity of the film can be increased and the heat insulating performance can be improved.

[0155] Since the total thickness of the oxide semiconductor film is 250 to 750 nm, the vertical emissivity can be kept low, the surface temperature of the low-emissivity layer can be increased, and the film has anti-scratch characteristics. And the transparency can be maintained. Since the heat transmission coefficient of the glass for refrigerators and refrigerators of the present invention is 4.00 W / m ² · K or less, the heat insulation can be improved.

[0156] Further, since the glass for refrigerators and refrigerators of the present invention has a visible light transmittance of 75% or more, it is possible to sufficiently ensure the internal confirmation of the products inside the refrigerator or refrigerator from the outside at room temperature. it can.

[0157] Further, in the refrigerator / refrigerator glass of the present invention, the oxide semiconductor film has a vertical emissivity of 0.2. Since it is 15 or less, radiant heat exchange between the inside of the freezer / refrigerator and the surface of the low radiation layer can be minimized while maintaining high transparency as a glass window.

Further, when a surface layer mainly composed of a composite oxide or a mixed oxide containing at least one element of silicon, aluminum and titanium is formed on the surface of the low-emissivity layer, the surface layer is It has a hydrophilic and water-retaining function and can reduce the contact angle even if water droplets adhere to it. it can. In particular, when the photocatalytically active substance is contained in the surface layer, organic dirt on the surface can be decomposed to maintain the hydrophilicity / water retention function for a long period of time.

Further, the double glazing or laminated glass using the glass for freezing / refrigerator of the present invention has excellent transparency, so that the glass for freezing / refrigerating is insulated while maintaining the desired transparency. The performance can be further improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view schematically illustrating one embodiment of a glass for freezing and refrigerator according to the present invention.

FIG. 2 is a view showing an example of a state in which the refrigerator / refrigerator glass of the present invention is attached to the refrigerator / refrigerator body.

FIG. 3 is a schematic configuration diagram schematically showing a CVD film forming apparatus.

FIG. 4 is a cross-sectional view schematically showing a second embodiment of the glass for a refrigerator / refrigerator according to the present invention.

FIG. 5 is a schematic configuration diagram schematically showing a sputtering apparatus.

FIG. 6 is a cross-sectional view schematically showing the first embodiment of the glass article according to the present invention.

FIG. 7 is a cross-sectional view schematically illustrating a second embodiment of the glass article according to the present invention.

FIG. 8 is a sectional view schematically showing a third embodiment of the glass article according to the present invention.

[Explanation of symbols]

Reference Signs List 1 glass substrate (glass plate) 2 SnO ₂ film 3 SiO ₂ film 4 SnO ₂ : F film (low reflection layer) 5 intermediate layer 6 laminated film (oxide semiconductor film) 11 TiO ₂ film (photocatalytic active layer) 13 surface layer

Claims (23)

[Utility model registration claims] 1. A freezing / refrigerating glass partitioning a first space in a room temperature atmosphere and a second space in an atmosphere lower than room temperature, wherein an oxide semiconductor film is formed on a surface of a glass plate on the second space side. Is formed, and the oxide semiconductor film is an intermediate layer including a first tin oxide film and a silicon oxide film sequentially formed on the surface of the glass plate on the second space side; And a low-emission layer including a second tin oxide film formed on the glass. 2. The glass for refrigerators and refrigerators according to claim 1, wherein the low-emissivity layer contains fluorine. 3. The total thickness of the oxide semiconductor film is 250.
The glass for refrigerators and refrigerators according to claim 1 or 2, wherein the thickness is from 750 to 750 nm. 4. The film thickness of the first tin oxide film is 10 to 5
0 nm, and the thickness of the silicon oxide film is 10 to 100.
and the thickness of the low-emissivity layer is 200 to 600 nm.
The refrigerator / refrigerator glass according to claim 3, wherein: 5. The freezing / refrigerating glass according to claim 1, wherein the heat transmission coefficient is 4.00 W / m ² · K or less. 6. The glass for refrigerators and refrigerators according to claim 1, wherein the visible light transmittance is 75% or more. 7. The oxide semiconductor film has a vertical emissivity of 0.5.
The glass for freezing / refrigeration according to any one of claims 1 to 6, wherein the number is 15 or less. 8. The refrigerator / refrigerator glass according to claim 1, wherein the thickness of the glass plate is 2 to 4 mm. 9. The freezing / refrigerating glass according to claim 1, wherein the glass is strengthened by air cooling. 10. The freezing / refrigerating glass according to claim 1, wherein a predetermined heat treatment is performed at a predetermined temperature after the formation of the low-emissivity layer. 11. A low emission layer having a surface layer mainly composed of a composite oxide or a mixed oxide containing at least one element of silicon, aluminum and titanium. Any one of claims 1 to 10
The glass for refrigerators and refrigerators according to the item. 12. The film thickness of the surface layer is 0.5 to 1000.
The glass for refrigerators and refrigerators according to claim 11, wherein 13. The refrigerator / refrigerator glass according to claim 11, wherein the surface layer contains a photocatalytically active substance. 14. The surface for the first space and the second space.
2. A predetermined antibacterial treatment is applied to at least one of the surfaces to the space.
14. The glass for refrigerators and refrigerators according to any one of claims 13 to 13. 15. A refrigerator / refrigerator body having a horizontal glass surface and a tilt angle of 0 to 135 ° with respect to a state in which the oxide semiconductor film is provided on a lower surface in a vertical direction. 2. The method according to claim 1, wherein:
The glass for freezing / refrigeration according to any one of 4 to 5. 16. The glass for a refrigerator / refrigerator according to claim 15, wherein the inclination angle is 0 ° to 60 °. 17. The method according to claim 1, wherein a plurality of glasses including the glass for a refrigerator / refrigerator according to claim 1 are disposed on the surface of the glass plate on which the oxide semiconductor film is formed, in the second space side. And a hollow layer is formed between the plurality of glasses. 18. The glass article according to claim 17, wherein the hollow layer is any one of an air layer, a heat insulating layer, and a reduced pressure layer. 19. A low-emissivity layer or a transparent film containing a low-emissivity substance is formed on a surface of at least one of the plurality of glasses facing each other facing the hollow layer. 19. The glass article according to claim 17 or 18, wherein 20. The low emission layer or a transparent film containing a low emission substance is disposed in the hollow layer at a distance from the surface of the glass. A glass article according to claim 1. 21. A plurality of glasses including the refrigerator / refrigerator glass according to claim 1, wherein the surface of the glass plate on which the oxide semiconductor film is formed is placed on the second space side. Characterized in that they are overlapped with each other via a transparent resin layer. 22. A glass article, wherein the two glass articles according to claim 17 are overlaid with a transparent resin layer interposed therebetween. 23. A surface for said first space and said second space.
2. A predetermined antibacterial treatment is applied to at least one of the surfaces to the space.
The glass article according to any one of 7 to 22.