JPH0588451U - Vacuum insulation container made of synthetic resin - Google Patents

Abstract

(57) [Abstract] [Purpose] Has sufficient gas barrier properties, prevents vacuum deterioration of the vacuum insulation layer due to outgas, suppresses radiation and heat loss from the inner container mouth, and further reduces the heat effect during use. Provided is a vacuum insulation container made of synthetic resin, which can sufficiently withstand even the above and can maintain the heat insulation performance as a heat insulation container for a long time. [Structure] An inner container 1 and an outer container 2 are joined and integrated at a mouth portion to form a double wall structure 5, and a space portion between the inner container 1 and the outer container 2 is evacuated to form a vacuum heat insulating layer 6. Along with
A synthetic resin vacuum heat insulation container in which at least the inner container 1 of the inner container 1 and the outer container 2 is formed of a synthetic resin,
A film thickness 1 made of copper is formed on the entire surface on the vacuum heat insulating layer 6 side of the inner container 1 and the outer container 2 made of synthetic resin.
Total thickness 10 having a plating layer 12 of less than 0 μm and a plating layer 13 made of another metal having a thermal conductivity lower than that of copper
The multi-layer plating film 10 having a thickness of 25 μm is formed.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a vacuum heat insulating container used as a thermos bottle, a heat retention lunch box or the like, and more particularly to a synthetic resin vacuum heat insulating container in which at least an inner container is made of synthetic resin.

[0002]

[Prior Art]

 Conventionally, a vacuum insulating container made of glass or metal made of stainless steel has been used as a thermos bottle, a heat-insulating lunch box, or the like. These glass or metal vacuum insulation containers are composed of an inner container, an outer container, and a space between the inner and outer containers, and the space is evacuated to form a vacuum heat insulation layer. This vacuum insulation container has excellent heat insulation properties and can maintain a high vacuum state for a long time, and therefore has the advantage of excellent heat retention properties. In addition to design restrictions, the product is heavy and inconvenient to carry.

Therefore, there has been proposed a synthetic resin vacuum heat insulating container using a synthetic resin that is easy to mold and is lightweight, instead of glass or metal. Similar to glass or metal, it has a double wall structure consisting of an inner container, an outer container and a vacuum heat insulating layer between them, and at least one of the inner container and the outer container is made of synthetic resin. Has been done. However, in this vacuum insulating container made of synthetic resin, the gas barrier property is deteriorated because the inner container and the outer container are made of synthetic resin. For this reason, a method of forming a metal plating film on the surfaces of the inner container and the outer container on the side of the vacuum heat insulating layer is usually adopted during manufacturing. This metal thin film not only enhances gas barrier properties, but also has the effect of reducing heat loss due to radiation, and is usually formed by a combination of chemical plating and electroplating. The thickness of this plating film is required to be 10 μm or more in order to have a sufficient gas barrier, and a thickness of 30 μm or less is appropriate in consideration of heat loss from the plating film. In addition, solder is used at the joint between the inner container and the outer container to achieve metallization. As described above, in the case of a synthetic resin vacuum insulation container, by metallizing the surface and joints of the synthetic resin part, the vacuum degree of the vacuum insulation layer is prevented from lowering, and Has been devised to maintain the performance of.

[0004]

[Problems to be solved by the device]

 By the way, in the case of a synthetic resin vacuum insulation container, the adhesion between the synthetic resin portion and the plating film is important in order to maintain the gas barrier property. However, when using this synthetic resin vacuum vessel insulation container, the hot water such as hot water or the cold water such as ice water is put in the inner container, and the surface temperature of the outer container becomes 80 ° C or more in the car in midsummer. Sometimes. When the heat insulating container is repeatedly heated or cooled in this way, the synthetic resin portion and the plated coating are naturally affected by heat, and each expands or contracts. Since the coefficient of thermal expansion of synthetic resin is generally 5 to 10 times that of metal, there is a difference in the amount of expansion and contraction between the synthetic resin part and the plating film, which results in stress between the synthetic resin part and the plating film. Occurs. The stress causes defects such as cracking and swelling in the plated coating, which lowers the adhesion of the plated coating and causes loss of gas barrier properties.

Furthermore, even if the plating film formed on the surface of the inner container has gas barrier properties, heat loss from the plating film may increase depending on the type and thickness of the plating film. Then, the amount of solid heat conduction at the mouth of the inner container becomes larger than that of the conventional metal vacuum heat insulating container, which causes a problem that the heat insulating performance deteriorates.

The present invention has been made in view of the above circumstances, and has sufficient gas barrier properties, prevents vacuum deterioration of the vacuum heat insulating layer due to outer gas, and prevents radiation and heat loss from the inner container mouth. To provide a synthetic resin vacuum heat insulation container that is equivalent to or less than the metal vacuum heat insulation container described above, and that can sufficiently withstand the heat effect during use and can maintain the heat insulation performance as a heat insulation container for a long time. Has a purpose.

[0007]

According to the present invention, an inner container and an outer container are joined and integrated at a mouth to form a double wall structure, and the space between the inner container and the outer container is evacuated. A vacuum heat insulating container made of synthetic resin, which is a vacuum heat insulating layer, and at least the inner container of the container and the outer container is made of synthetic resin. A plating film having a total film thickness of 10 to 25 μm is formed on the entire surface on the heat insulating layer side, including a plating layer made of copper and having a film thickness of less than 10 μm, and a plating layer made of another metal having a thermal conductivity smaller than that of copper. That was the solution.

[0008]

[Action]

 The synthetic resin vacuum insulation container of the present invention has a metal coating formed on the surface of the inner container or the outer container, and has a multi-layer structure including a plating layer made of highly ductile copper and a plating layer made of another metal. Since it is a plated coating, each layer buffers expansion and contraction caused by heat. Moreover, since the plating film is a multi-layer metal film that is made of copper and another metal whose thermal conductivity is smaller than that of copper and has a total film thickness of 10 to 25 μm, it is a solid at the mouth of the inner container. The heat loss due to heat conduction can be made equal to or less than that of a conventional vacuum heat insulating container made of metal. In addition, the adhesion between the synthetic resin portion and the plating film is improved.

[0009]

【Example】

 An embodiment of the synthetic resin vacuum insulation container according to the present invention will be described below with reference to FIGS. 1 is a sectional view showing an embodiment of the present invention, FIG. 2 is a partially enlarged sectional view of an inner container thereof, FIG. 3 is a sectional view of an inner container, and FIG. 4 is a sectional view of an outer container.

Reference numeral 1 in FIG. 1 is an inner container. The inner container 1 is a bottomed cylindrical container having a U-shaped cross section, which is molded from a synthetic resin such as ABS resin or polypropylene. Further, reference numeral 2 is an outer container. Similar to the inner container 1, the outer container 2 is a cylindrical container having a U-shaped cross section, which is made of a synthetic resin such as ABS resin or polypropylene and covers the outer side of the inner container 1 with a predetermined gap. .. The outer periphery of the mouth of the inner container 1 and the outer periphery of the mouth of the outer container 2 are provided with annular flanges 3 and 4, respectively, which project outward, and the lower surface of the content container flange 3 and the outer container flange are provided. Since the upper surface of 4 is joined via the plated coating 10 as described later, the inner container 1 and the outer container 2 are joined and integrated at their respective mouths, and the double wall structure 5 is formed. Has been formed. A low melting point solder is used to connect the inner and outer containers 1 and 2. An opening 7 for exhaust is provided at the bottom of the outer container 2, and the space between the exhaust opening 7 and the inner and outer containers 1, 2 is vacuum-exhausted to form a vacuum heat insulating layer 6. ing. The exhaust opening 7 is sealed by a sealing plate 8. As the sealing plate 8, a metal sealing plate or a synthetic resin sealing plate coated with a plating film as described later is used.

As shown in FIG. 2, on the outer surface of the inner container 1, that is, the entire surface on the side of the vacuum heat insulating layer 6, a chemical Ni plating layer 11 is used as a base, and the upper surface thereof is provided with a glossy electric Cu plating with high ductility. The layer 12 is further formed with a bright electric Ni plating layer 13 made of metallic Ni 2 having a thermal conductivity smaller than that of Cu on the upper surface of the layer 12 to provide a multi-layer plating film 10. In this multi-layer plating film 10, the base chemical Ni plating layer 11 is formed to a film thickness of about 0.8 to 1 μm, and the glossy electric Cu plating layer 12 is formed to a film thickness of about 1 to 9 μm. The glossy electric Ni plating layer 13 thereon is formed so that the total thickness of the glossy electric Ni plating layer 13 and the light electric Cu plating layer 12 is within the range of 10 to 25 μm. The bright electric Cu plating layer 12 is formed by the electroplating method using the base chemical Ni plating layer 11 as a conductor, and the bright electric Ni plating layer 13 is also formed by the electroplating method. Here, the total film thickness of the electroplated coating 10 composed of the bright electric Cu plating layer 12 and the bright electric Ni plating layer 13 is set to 10 to 25 μm because the gas barrier property is less than 10 μm. This is because the vacuum is difficult to maintain for a long time, and the performance as a vacuum insulation container cannot be maintained for a long time. Further, when it exceeds 25 μm, the plating film 10 swells or peels off due to the heat effect. This is because defects such as the above occur and the adhesion of the plating film 10 is lowered, and the gas barrier property is rapidly lost.

Further, the same multi-layer plating film 10 as described above is formed on the entire inner surface of the outer container 2, that is, the surface on the vacuum heat insulating layer 6 side. A multi-layer plating film 10 is also formed on the lower surface of the inner container flange 3, the upper surface of the outer container flange 4, and the sealing surface of the exhaust opening 7.

Next, a method for manufacturing the synthetic resin vacuum insulation container 15 will be described. First, the inner container 1 and the outer container 2 each having a flange portion at the mouth are formed of a synthetic resin such as ABS resin, polypropylene, or polycarbonate. An exhaust opening 7 is provided at the bottom of the outer container 2. Then, on the outer surface of the inner container 1 and the lower surface of the collar portion 3, a chemical Ni plating layer 11 is continuously formed on the entire surface thereof, and a bright electric Cu plating layer 12 is further formed on the chemical Ni plating layer 11 as a conductor. Then, a glossy electric Ni plating layer 13 is sequentially formed, and a multi-layer plating film 10 is provided. Similarly, the multilayer plating film 10 is continuously formed on the entire inner surface of the outer container 2, the upper surface of the collar 4 and the sealing surface of the exhaust opening 7 in the same manner. Then, the flange portions 3 and 4 of the inner and outer containers 1 and 2 are joined and integrated by a low melting point solder to form a main body 5 having a double wall structure. Then, after evacuating the space between the inner and outer containers 1 and 2 from the exhaust opening 7 at the bottom of the outer container 2, the sealing plate 8 is attached to the sealing surface of the exhaust opening 7. Is fixed with a low melting point solder, the space is vacuum-sealed, and the vacuum heat insulating layer 6 is formed. It should be noted that the sealing plate 8 should be hermetically sealed with a low melting point solder by using a metal or a plate coated with a plating film 10 having the same gas barrier property as the inner and outer containers 1 and 2 described above. You can The synthetic resin vacuum insulation container 15 thus manufactured has sufficient gas barrier properties and can prevent the vacuum insulation layer 6 from being deteriorated in vacuum due to outgas. Moreover, the radiation and heat loss from the joint between the inner and outer containers 1, 2 are equal to or less than those of the conventional metal vacuum insulation container, and furthermore, they can withstand the heat effect during use. There is no strain cracking or peeling of the plating film 10, and the performance as a heat insulating container can be maintained for a long time.

Next, by specifically showing examples and comparative examples, a test of adhesion and gas barrier property of the plating film and a test of heat retention performance were conducted to clarify the effect of the synthetic resin vacuum heat insulation container of the present invention. To

[Test of Adhesion and Gas Barrier Property of Plating Coating] (Example 1) First, a chemical plating Ni plating layer was formed to a thickness of 1 μm on the surface of a container injection-molded with ABS resin. Then, a multi-layered plating film consisting of a glossy electric Cu plating layer and a glossy electric Ni plating layer was formed thereon to have a thickness of 25 μm. A plurality of these containers were prepared, and a heat cycle test was performed on each container to evaluate the adhesion of the plating film. In the heat cycle test, the process of raising and lowering the ambient temperature to + 20 ° C to -20 ° C, -20 ° C to + 20 ° C, + 20 ° C to -80 ° C, and leaving for 30 minutes at each temperature is defined as one cycle. Was repeated for 5 cycles. As a result, no swelling was observed in the plated coatings of all the containers. (Comparative Example 1) A container was prepared in the same manner as in Example 1 except that the thickness of the plating film was formed to be less than 10 µm, and its gas burrability was evaluated by a He permeation test. As a result, He permeation of the order of 10 ⁻⁹ Torr · l / sec was detected in all the containers. Comparative Example 2 A container was prepared in the same manner as in Example 1 except that the thickness of the plated coating was 30 μm, and the adhesion of the plated coating was evaluated by the heat cycle test. As a result, swelling was observed in the plating of some containers. Further, when a He permeation test was carried out on a container in which no swelling was observed, no He permeation was detected. From the above results, it was found that the thickness of the multilayer plating film is preferably in the range of 10 to 25 μm. Comparative Example 3 Next, a chemical Ni plating was formed on a container injection-molded with ABS resin, and a glossy electric Ni plating layer was formed thereon so as to have a thickness of 10 μm. Using this container, the adhesion of the plating and the gas barrier property were evaluated by a heat cycle test and a He permeation test. As a result, cracking occurred in the bright electric Ni plating film, and the permeation of He was detected. From this result, when the electric Cu plating layer is not provided and only the plating layer made of Ni, which is inferior to Cu in ductility, is provided, even if the film thickness is appropriate, there is a problem such as cracking. I understood it.

[Test of Thermal Insulation Performance] (Example 2) After forming a chemical Ni plating layer as a base on inner and outer containers injection-molded with ABS resin, a glossy electric Cu plating layer is formed to a thickness of 9 μm. Then, a bright electroplated Ni plating layer having a thickness of 16 μm was formed thereon. (Example 3) After forming a chemical Ni plating layer as a base on an inner / outer container injection-molded with ABS resin, a gloss electric Cu plating layer was formed to a thickness of 5 μm, and a gloss electric The Ni plating layer was formed to a thickness of 20 μm. (Comparative Example 4) A stainless steel vacuum heat insulating container having the same shape as the synthetic resin vacuum heat insulating containers of Examples 2 and 3 was used. A heat insulation performance test was performed using the vacuum heat insulating containers of Examples 2 and 3 and Comparative Example 4. The heat retention performance test was carried out in accordance with JIS standard, and hot water was put in each vacuum heat insulation container and evaluated by measuring the temperature of the hot water after standing for 6 hours. As a result, the synthetic resin vacuum insulation container of Example 2 has a temperature of 49.5 ° C., the synthetic resin vacuum insulation container of Example 3 has a temperature of 53.0 ° C., and the stainless steel vacuum insulation container of Comparative Example 4 has a temperature of 50.0 ° C. The value was shown. From the above results, the heat insulation performance of the synthetic resin vacuum insulation container of Example 2 was equivalent to that of the conventional stainless vacuum insulation container. It was also confirmed that the vacuum insulation container made of synthetic resin of Example 3 had better heat retention performance than the vacuum insulation container made of stainless steel. This is because the solid heat transfer amount at the inner container mouth of the synthetic resin vacuum heat insulating container of Example 3 was smaller than that of the stainless steel vacuum heat insulating container.

[0017]

[Effect of the device]

 As explained above, the synthetic resin vacuum heat insulation container of the present invention has a perfect gas barrier property without the plating coating being distorted or expanded and peeled off by the thermal influence. It also prevents vacuum deterioration of the vacuum insulation layer due to outgas, and the radiation and heat loss from the mouth of the inner container are equal to or less than those of the metal vacuum insulation container. In addition, it can sufficiently withstand the heat effect during use, and can maintain its performance as a vacuum insulation container for a long time. In addition, the vacuum insulation container made of synthetic resin is much lighter than the vacuum insulation container made of metal, which makes it convenient to carry and easy to mold. There are also advantages such as large.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a synthetic resin vacuum heat insulating container of the present invention.

FIG. 2 is a partially enlarged cross-sectional view of a multi-layer plating film formed on the inner container of the synthetic resin vacuum heat insulating container of FIG.

FIG. 3 is a cross-sectional view of an inner container in the synthetic resin vacuum heat insulating container of FIG.

FIG. 4 is a cross-sectional view of an outer container in the synthetic resin vacuum heat insulating container of FIG.

[Explanation of symbols]

 1 Inner Container 2 Outer Container 5 Double Wall Structure 6 Vacuum Insulation Layer 10 Multi-Layered Coating 12 Bright Electric Ni Plating Layer 13 Bright Electric Cu Plating Layer 15 Synthetic Resin Vacuum Insulation Container

Continuation of the front page (72) Minoru Morita 4-320 Tsukagoshi, Sachi-ku, Kawasaki City, Kanagawa Prefecture

Claims (1)

[Scope of utility model registration request] 1. An inner container and an outer container are joined and integrated at a mouth to form a double wall structure, and a space between the inner container and the outer container is evacuated to form a vacuum heat insulating layer. vessel,
A synthetic resin vacuum heat insulating container in which at least an inner container is formed of a synthetic resin, wherein the inner surface of the outer container and the outer container formed of synthetic resin are made of copper on the entire surface on the vacuum heat insulating layer side. Film thickness 10 μm
Vacuum heat insulation made of synthetic resin, wherein a multi-layer plating film having a total film thickness of 10 to 25 μm is formed, which has a plating layer of less than 1 and a plating layer made of another metal having a lower thermal conductivity than copper. container.