JP2001354456A - Low pressure sealed double-glazed unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inhibit the reflection of light from metallic spacers scattered in a gap in a low pressure sealed double-glazed unit so as to hold the gap. SOLUTION: An oxide coating film is formed on the surface of each metallic spacer produced from a metal having <=100 W/m deg.C heat conductivity by heat treatment or the like. The heat treatment is carried out at >=300 deg.C in air.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the construction field of houses, office buildings, store buildings, etc., automobiles, vehicles, ships and so on.
The present invention relates to a low-pressure double glazing having high heat insulating performance used for openings in the transportation field such as an aircraft, and the equipment field such as a freezer, a freezer showcase, and a constant temperature and humidity chamber.

[0002]

2. Description of the Related Art In recent years, in order to create a comfortable and healthy living environment with excellent energy saving, double glazing having heat insulation performance has been used more frequently than ever before and has been rapidly spreading.
Correspondingly, requirements for heat insulation performance, sound insulation performance, design, and the like for double-glazed glass have become strict.

[0003] A low-pressure multilayer glass has been proposed which reduces the pressure in the gap between the glass sheets in order to impart high heat insulation or sound insulation to one of the multilayer glasses. However, in the case of low pressure double glazing, the sheet glass is bent by the atmospheric pressure load, and the sheet glasses come into contact with each other, so that the heat insulating performance cannot be exhibited. In order to prevent this, a spherical or columnar metal spacer made of stainless steel or the like is provided in the gap to maintain the gap.

[0004] However, due to the metallic luster characteristic of metals,
There is a concern that the low-pressure double-glazed glass may appear glaring due to the reflection of sunlight or the like from the metal spacer, and that there may be a problem in traffic safety due to glare.
Therefore, the metal-specific luster of the metal spacer is reduced,
Suppressing the reflection of light is an important technique for eliminating defects in appearance of the low-pressure double-glazed glass and enabling safe use.

[0005]

SUMMARY OF THE INVENTION In a low pressure double glazing in which a metal spacer is interspersed in a gap to maintain the gap of the low pressure double glazing, suppressing the reflection of light from the metal spacer is achieved by a low pressure double glazing. This is a major issue for improving the appearance of the laminated glass so that it can be used safely.

[0006]

According to the low pressure double glazing of the present invention, the peripheral edges of a plurality of opposing sheet glasses are sealed,
The gap between the glass sheets is depressurized, and the metal spacers scattered in the gap are formed with an oxide film on the surface of the metal spacer in the low-pressure double-layer glass holding the gap. It is a low pressure double glazing characterized by the following.

The oxide film formed on the surface of the metal spacer is formed by heating the metal spacer in air at a temperature of 300 ° C. or higher. 100 ° C thermal conductivity
It is characterized by being made of a metal of W / m ° C or lower.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION A metal spacer for maintaining the interval between low pressure double glazings is formed of stainless steel, iron steel, titanium, nickel, chromium steel, carbon steel, or the like. In addition, an oxide film is formed on the surface.

As a method of forming an oxide film on a metal surface, there are a method of treating with an acidic solution and a method of anodizing. Further, a method of performing heat treatment at 300 ° C. or more in an atmosphere in which oxygen gas is present, for example, in air, is simple and preferable. Further, a metal film of silver, copper, tin, zinc or the like may be formed on the metal surface by plating or the like, and the metal film may be oxidized.

In order to reduce the heat conduction through the metal spacer, the heat conductivity of the metal spacer at 25 ° C. is 1
It is preferably at most 00 W / m ° C.

When the metal spacer on which such an oxide film is formed is used for holding the gap of the low-pressure double-glazed glass, the low-pressure double-glazed glass excellent in appearance can be obtained without noticeable metal spacers.

Since the reflection by the metal spacer is particularly conspicuous on the surface in contact with the glass sheet, an oxide film may be formed only on the surface of the micro spacer in contact with the glass sheet.

The visible light reflectance of the metal spacer is as follows:
A value measured by a method based on JIS R 3106,
It is preferably 40% or less, and more preferably 30% or less, because visible light reflection by the metal spacer can be suppressed.

As the shape of the metal spacer, shapes such as a sphere, a column, a cone, a line, and a mesh can be used.

[0015] The two or more sheet glass facing each other are clear float sheet glass, glass with a low radiation film, heat ray absorbing sheet glass, heat ray reflecting sheet glass, high-performance heat ray reflecting sheet glass, wire sheet sheet glass, net sheet sheet glass, tempered sheet glass, and tempered glass. Glass,
Various types of plate glass such as double strength glass, low reflection plate glass, high transmission plate glass, ground glass, tapesti (frost) glass, ceramic printing glass, laminated glass can be appropriately combined. At least one of these various plate glasses is coated with a special metal film. It is preferable to use a coated low radiation plate glass because the heat insulating performance is enhanced. As the low-emissivity film, not only a film formed by a CVD method having a relatively high vertical emissivity but also a film formed by a sputtering method having a low vertical emissivity can be adopted.

Further, JIS R3106-1985
(Test method for transmittance, reflectance and solar heat gain of sheet glass)
Vertical emissivity of 0.20 or less, preferably 0.1
It is preferable to use one or more low-emission glasses of 0 or less, or two low-emission glasses having a vertical emissivity of 0.35 or less, preferably 0.25 or less.

The thickness of the sheet glass is usually 1.9 mm.
The above materials are used, however, in the case of tempered glass, especially in the case of chemically tempered glass, etc.
Those having a size of 9 mm or less can also be used. Further, other than the inorganic glass, a resin glass such as an acrylic plate and a polycarbonate plate may be used, and there is no particular limitation.

The sealing material used for the peripheral edge of the low-pressure double glazing is made of polyisobutylene, silicone, polysulfide, polyethylene, polypropylene, polyvinylidene fluoride (PVDF) or fluoroelastomer for liquid injection molding manufactured by Shin-Etsu Chemical Co., Ltd. "SIFEL610", "SIFEL61
2 "," SIFEL650 "," SIFEL611 ",
Fluorine-based resins such as "X-70-631" (trade name), polyacrylonitrile, polymethacrylonitrile,
Monsanto “Lopag” (trade name), So
"Barrex" (trade name) manufactured by hio, polyamide such as polyethylene terephthalate, nylon 6, nylon 66, "Super Back Seal" manufactured by Anelva
(Trade name) such as epoxy resin, polyvinyl chloride, polyvinyl fluoride, polyimide, etc., and if necessary, a tackifier or a plasticizer, etc., and calcium carbonate as a filler if necessary , Talc, mica, silica, carbon black, ultrafine powdered silica, polymer material composited using ultrafine powder titania, etc., Sn, PB,
In, Zn-Sn based alloy, Pb-Sn based alloy, Bi-S
Low melting point metal such as n-based alloy, In-Sn-based alloy, lead borate glass, lead zinc borate glass, lead borosilicate glass, lead zinc borosilicate round glass, phosphate glass, fluorophosphorus Timely use of sealing materials such as silicate glass and low-melting-point glass combined with crystals having a low coefficient of thermal expansion such as lead titanate, lithium silicate-based crystals, and aluminosilicate-based crystals as required it can.

[0019]

EXAMPLES Example 1 Table 1 shows that a sheet of stainless steel (SUS304) having a size of 50 mm × 50 mm and a thickness of 0.2 mm was subjected to one sheet at each temperature.
This is the visible light reflectance of a sample that was heat-treated in air for 0 minutes.

[0020]

[Table 1]

The heat treatment at 300 ° C. or more lowers the visible light reflectance, and the heat treatment at 500 ° C. reduces the visible light reflectance to about 1/3 of that before the heat treatment, due to the metallic luster of the metal spacer. It can be seen that the glare is reduced. Also, other stainless steel SUS316, 43
The same result was obtained at 0.

A SUS304 sheet having a thickness of 0.2 mm was punched out by a press to form a cylinder having a diameter of 0.5 mm and a height of 0.2 mm. This was heat-treated at 500 ° C. for 10 minutes to obtain a metal spacer 1.

The metal spacers 1 are arranged at a pitch of 20 mm × 20 mm on a glass plate 3 having a size of 1000 mm × 1000 mm and a thickness of 3 mm by a float method.
In one corner of the glass sheet, 50mm from the side
A hole 4 of 2 mmφ is provided at a position of 50 mm.

Around the sheet glass, a width of 8 mm and a height of 0.25
A super-back seal (trade name, manufactured by Anelva Co.) of an epoxy resin mixed with 30% by weight of zeolite powder having a diameter of 50 μm and 30% by weight was applied to obtain a peripheral sealing material 5. A glass plate 6 coated with a low-emissivity film of the same size as the glass plate 3 and having a vertical emissivity of 0.1 was combined with a glass plate 6 while applying a sufficient load to form a multilayer body having an interval of 0.2 mm. A glass exhaust pipe 7 having an outer diameter of 2 mmφ and an inner diameter of 1.5 mmφ was connected to the hole 4, and a sealing material 5 was applied to the gap.

The multilayer body is heated at 110 ° C. for 1 hour to harden the resin component of the sealing material 5 to form a strongly integrated panel.
While maintaining the atmosphere temperature of 110 ° C., the exhaust glass tube 7
Is connected to an exhaust device (not shown), and the gap between the panels is
Then, the exhaust glass tube 7 was heated and sealed to obtain a low-pressure double-glazed glass 2 in which the gap was reduced in pressure.

The low pressure double glazing 2 thus produced has an initial dew point of -70 ° C. or less and a heat transmission coefficient of 1.5 W.
/ m ² ° C, it was confirmed that dew condensation hardly occurred and good heat insulating performance was obtained.

When the surface of the metal spacer 1 is oxidized to form an oxide film and is not oxidized, the metal spacer 1 is oxidized in a room illuminated by a general-purpose fluorescent lamp. If it is not treated, the metal spacer 1 can be recognized at a distance of 1 m from the low-pressure double glazing. On the other hand, if the oxide film has been formed by the oxidation treatment, the metal spacer 1 cannot be recognized. It was possible to obtain a low-pressure double glazing having an excellent appearance in which the spacer 1 was not noticeable.

[0028]

According to the present invention, the low pressure double glazing using a metal spacer having an oxide film formed on the surface to suppress the reflectance for holding the gap can suppress the reflection of light from the metal spacer.
A low-pressure double-glazed glass having a good appearance is provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a low-pressure double glazing in Example 1.

[Explanation of symbols]

 1. Metal spacer 2. Low pressure double glazing 3. Sheet glass 4. 4. Hole serving as exhaust opening Sealing material 6. 6. Glass plate with low radiation film Exhaust pipe

Claims (3)

[Claims] 1. The method according to claim 1, further comprising: sealing a peripheral edge of each of the plurality of glass sheets facing each other to reduce a pressure in a gap between the glass sheets; metal spacers scattered in the gap hold the gap. A low pressure double glazing, wherein an oxide film is formed on a surface of a metal spacer. 2. The low-pressure composite according to claim 1, wherein the oxide film formed on the surface of the metal spacer is formed by heating the metal spacer to 300 ° C. or more in air. Layer glass. 3. The low pressure double glazing according to claim 1, wherein the metal spacer is made of a metal having a thermal conductivity at 25 ° C. of 100 W / m ° C. or less.