JPH0683689B2 - Window frame for frozen storage case - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a highly heat-insulating refrigeration showcase assembled from transparent panels, and more specifically, to fog generated when the door of the refrigeration showcase is opened and closed. The present invention relates to a window frame for a refrigeration showcase, which is improved with respect to prevention of the above.

[Conventional technology]

With the spread of frozen foods, frozen showcases have become indispensable in grocery stores. Conventionally, there was a frozen showcase known by the general name of ice stocker that is seen in over-the-counter sales of ice cream, but only one side of the top of the showcase is made up of a transparent window frame and the other side is made of heat insulating material. And the thermal efficiency was relatively good,
These are comparatively small, and when it comes to a large frozen showcase, there is a limit in thermal efficiency and the like.

Further, in recent years, a frozen showcase has been developed into a show window, and a large-sized frozen showcase having a large transparent window area has been generalized. In this type of frozen showcase, the transparent portion is generally a glass panel, but the heat loss is extremely large. For this reason, it has become common to use transparent glass parts of these frozen showcases as panels made of double glass.

Recently, heat-reflecting films, which are more energy-saving, are joined to the above-mentioned panel and bonded to each other, and have been used for the transparent window portion. (For example, the actual exploitation 54
−96464 publication, etc. ) [Problems to be solved by the invention] With these improvements, the energy loss of the frozen showcase has been greatly improved, but another condition of the frozen showcase is that it is always transparent and does not fog. Is required. It is common for the doors of the frozen showcases to be opened and closed frequently, but in such a case, the problem was that the inside of the door in the low temperature state could come into contact with the atmosphere on the high temperature side to cause dew condensation by opening the door. . If condensation forms inside the door,
Due to the low temperature inside the frozen showcase, it freezes in a short time, and the wall surface becomes cloudy, making it difficult to see the products inside. Such a phenomenon has become a remarkable problem since the double glass has been widely used for the window frame of the frozen showcase.

In order to eliminate the disadvantage that this frozen showcase freezes and causes condensation on the high temperature side of the door or frost on the low temperature side of the door, conventionally, you should wipe the inside of the door well with a dry cloth before closing it. , Was very inconvenient. Another method to overcome this drawback is to use two transparent acrylic plates coated with a surface active agent, etc. and enclose dry air or gas to prevent dew condensation. When applied to a complete, large-scale frozen showcase, the thermal insulation is likewise insufficient. (For example, Japanese Utility Model Publication No. 38-16865.) Furthermore, a transparent surface heating element, for example, a thin film such as tin oxide or indium oxide is laminated on the inside of the door, and moisture is condensed by appropriately energizing this. Had been evaporated. However, this method is also backward from the viewpoint of energy saving, and the accessory equipment of the frozen showcase becomes complicated,
It is hard to say that the problem of condensation on the inner surface of the frozen showcase has been solved.

SUMMARY OF THE INVENTION The present invention has been made to improve the problems of the prior art as described above, to be sufficiently applicable to a large-sized frozen showcase, to further improve the heat insulating property and to prevent dew condensation on the wall surface.

[Means for solving problems]

In order to solve the above problems, as a result of intensive studies, the present invention has been completed.

That is, the present invention is used for a door portion in a frozen showcase manufactured by using a transparent panel (2) which is constructed by assembling two transparent plates (1) made of inorganic glass or organic glass with a certain gap. Inside the panel (2)
A transparent high-refractive-index metal oxide is formed on a transparent resin film by laminating a film (3) having a transparent antifogging property-imparting layer, and between two transparent plates (1) of a transparent panel (2). A frozen show characterized in that a heat ray reflective film (4) obtained by laminating, then laminating a metal film, and further laminating a transparent high-refractive-index metal oxide is sandwiched at regular intervals and assembled. It is a window frame for a case.

The film (3) having an antifogging property-imparting layer as used in the present invention means, for example, a film prepared by mixing a transparent soft vinyl chloride resin film and a surfactant at the time of forming both films, or partially cross-linked polyvinyl alcohol. Films and the like correspond to this. In addition, an antifogging paint, for example, a mixture of the soft vinyl chloride resin and a surfactant dissolved in an organic solvent and dried, or a copolymer of hydroxyethyl methacrylate and a vinyl compound having a copolymerizability therewith is used. Examples include those applied and dried with an organic solution. Other commercially available anti-fog films and anti-fog paints can all be provided as the material of the present invention.

Since these antifogging materials generally have organic substances on the surface in many cases, they tend to be stained more easily than the conventionally used glass panels and tend to be economically deteriorated. The anti-fog film is more preferable than the fog paint because it can be easily replaced. When adopting an anti-fog film, as mentioned above, it is preferable to use an adhesive so that it can be easily replaced, and when strongly bonding with an adhesive, the old adhesive becomes a transparent plate at the time of replacement. Inconveniences such as being left behind or being difficult to peel off the anti-fog film from the transparent plate may occur. When an anti-fog coating is used, the coating can be done in a much thinner film than the anti-fog film, saving the material. Although it is possible to work by wiping with a small amount of solvent even when repainting due to stains and aging, it is preferable to use a film from the above point.

The material of the transparent plate (1) used in the present invention is selected from inorganic glass or organic glass such as acrylic resin and polycarbonate resin, but it is preferable to use inorganic glass from the viewpoint of surface hardness and durability.

Further, the heat ray reflective film used in the present invention can be easily formed by laminating a transparent high refractive index metal oxide on a transparent resin film, then laminating a metal film, and further laminating a transparent high refractive index metal oxide. Can be manufactured, for example, Mitsui Toatsu Chemical Co., Inc., heat mirrors are commercially available,
Various kinds of commercially available films for heat ray reflection can be used.

[Action and effect]

The antifogging treatment effect of the present invention is more effective when the frozen showcase door portion is highly insulated, and therefore the door window frame has two transparent plates (1).
Further effects can be expected in the case of a combination of the above with a constant spacing, or in the case of a panel structure having more excellent heat insulation. Particularly, a transparent panel assembled by sandwiching a heat ray reflective film (4) with a certain gap between the two transparent plates (1) or one of the two transparent plates (1) is provided with a heat ray. It is clear that a transparent panel or the like assembled by bonding and laminating the reflective film (4) has a good heat insulating effect, and in particular, the heat insulating effect of the former one is remarkably improved. Therefore, this method of the present invention is used. Thus, the effect of preventing dew condensation was remarkably improved by sandwiching the heat ray reflecting film and further subjecting the transparent plate to antifogging treatment.

Frozen showcase panels assembled by the above method and subjected to anti-fog treatment have a high degree of heat insulation, and can be opened and closed under the hot and humid conditions of summer. Also does not fog inside the panel.

In recent years, frozen showcases with highly heat-insulating properties are generally desired, and in particular, due to the tendency to increase in size, the phenomenon of fog inside the transparent panel has not been sufficiently resolved, so heat-insulating panels are expected. It's not as popular as it gets. Therefore, although it was unavoidable to take emergency measures such as using a panel with a slightly large energy loss, the present invention makes it possible to prevent fogging at the same time while imparting a high degree of heat insulation, and to a large frozen showcase. The fact that it can be applied also has great effects in terms of both energy saving and the value of the products displayed in the frozen showcase.

〔Example〕

 Hereinafter, the present invention will be described with reference to examples.

Examples 1 and 2 As shown in FIG. 1, a heat ray reflective film (trade name; manufactured by Mitsui Toatsu Kagaku Co., Ltd.) between two pieces of float glass having a thickness of 3 mm.
The heat mirrors 88) were arranged with a certain interval shown in Table-1. Further, a film having an antifogging property-providing layer shown in Table 1 was attached to one glass surface to prepare a window frame for a frozen showcase. The glass surface to which the anti-fog film was attached was set to -10 ° C in Example 1, and the glass surface in Example 2 was used.
Then, the other side was faced to a constant temperature and humidity chamber of -15 ° C and 25% and 65% RH. As a result of leaving it in this state for 24 hours, Table-1
As shown in, no condensation occurred on the glass surface at 25 ° C (outside of the refrigerator). The heat transmission coefficient at this time was measured, and each value is shown in Table-1. Furthermore, after that, the window frame for the frozen showcase was opened and closed twice, but no frost was observed on the minus temperature side (inside the refrigerator).

However, the antifogging film is a film obtained by partially cross-linking polyvinyl alcohol in Example 1, and in Example 2,
A polyethylene terephthalate film laminated with a copolymer of hydroxyethyl methacrylate and N-isopropylacrylamide was used.

Comparative Example 1 As shown in FIG. 2, two transparent plates each having a 3 mm-thick acrylic plate coated with a surfactant on one side were provided with air spaces shown in Table 1 to prepare a window frame for a frozen showcase. .

When the same test as in Example 1 was conducted, it was confirmed that dew was generated on the surface of the transparent plate and the surface of the transparent plate was below the dew condensation limit temperature.

The measured values of the heat transmission coefficient at this time were as shown in Table-1.

Further, when the window frame for the frozen showcase was opened and closed twice, frost was generated inside.

Comparative Example 2 A heat ray reflection film (trade name: Mitsui Toatsu Chemicals heat mirror 88) was attached to a float glass having a thickness of 3 mm with an adhesive, and the heat ray reflection film was placed on the inner surface to expose the float glass. The window frames for frozen showcases were prepared by arranging them at intervals shown in FIG.

One glass surface was exposed to a constant temperature and humidity chamber of minus 15 ° C and the other 25 ° C and 65% RH.

When left in this state for 24 hours, dew condensation occurred on the glass surface at 25 ° C.

The heat transmission coefficient at this time is as shown in Table-1. Also,
When the window frame for the frozen showcase was opened and closed twice, frost was generated inside.

Comparative Example 3 As shown in FIG. 3, a heat ray reflective film (trade name; heat mirror 88, manufactured by Mitsui Toatsu Chemicals, Inc.) was attached to a float glass having a thickness of 3 mm with an adhesive, and the heat ray reflective film was placed on the outer surface. And the float glass was arranged at the intervals shown in Table-1. A polyethylene terephthalate film in which a copolymer of hydroxyethyl methacrylate and N-isopropylacrylamide was laminated was attached to the glass surface on the low temperature side to prepare a window frame for a frozen showcase.

The glass surface pasted with anti-fog film is -15 ° C,
The other was faced to a constant temperature and humidity chamber at 25 ° C and 65% RH. When left in this state for 24 hours, the glass surface on the 25 ° C side
Condensation has occurred.

The heat transmission coefficient at this time is as shown in Table-1.

Further, the window frame for the frozen showcase was opened and closed twice, but no frost was found inside.

The above results are summarized in Table 1.

〔The invention's effect〕

From the above results, the value of the heat transmission coefficient representing the index of heat insulation is significantly improved compared to the value of the comparative example, the heat insulation is significantly improved, frost on the inside of the refrigerator, dew condensation on the outside of the refrigerator The occurrence of

[Brief description of drawings]

Figure 1 is designed so that the outside (outside) of the panel (2) made by laminating two transparent plates (1) with a certain gap between them is the atmospheric temperature (high temperature side) and the inside is the inside of the frozen showcase (low temperature side). The heat ray reflective film (4) was sandwiched between the two transparent plates by laminating a film (3) having an antifogging property-imparting layer on the surface corresponding to the inner side, and further sandwiching a heat gap between the two transparent plates. 1 is a cross-sectional view of a panel (2) having a layered structure according to Examples 1 and 2 of the present invention. FIG. 2 shows that the outside of a panel (2), which is made by laminating two transparent plates (1) with a certain gap, is the atmospheric temperature (high temperature side),
A cross-section that is designed so that the inside is the inside of the frozen showcase (low temperature side), and illustrates the structure of a panel (2) in which a film (3) having an antifogging property-imparting layer is laminated on the surface corresponding to the inside. It is a figure and corresponds to the above-mentioned comparative example 1. FIG. 3 is a sectional view of a panel having a structure in which a heat ray reflective film (4) is attached to a transparent plate (1) on the outer side (high temperature side) of the panel (2) assembled in FIG. This corresponds to Comparative Example 3 described above.

Claims (1)

[Claims] 1. A frozen showcase manufactured by using a transparent panel (2) assembled from two transparent plates (1) made of an inorganic glass or an organic glass with a certain gap therebetween. Inside the used panel (2),
A transparent high-refractive-index metal oxide is formed on a transparent resin film by laminating a film (3) having a transparent antifogging property-imparting layer, and between two transparent plates (1) of a transparent panel (2). A frozen show characterized in that a heat ray reflective film (4) is formed by laminating, then laminating a metal film, and further laminating a transparent high refractive index metal oxide, with a certain gap therebetween. Window frame for the case.