JP3490426B1 - Vacuum heat insulating material, and refrigeration equipment, cooling / heating equipment using the same, and vacuum heat insulating material core material and manufacturing method thereof - Google Patents

Abstract

[PROBLEMS] To provide a vacuum heat insulating material having excellent heat insulating performance, light weight, excellent productivity, rigidity and high flatness accuracy in a heat insulation and cooling device such as a refrigerator, a freezer, and a vending machine, and a vacuum heat insulating material core used therefor A material and a method for manufacturing the same are provided. Moreover, the refrigerator which consists of a heat insulation box with high heat insulation performance and was excellent in appearance quality with energy saving is provided. SOLUTION: A vacuum heat insulating material comprising a board-shaped core material and a jacket material enclosing the core material, the inside of which is sealed after decompression, and the board-shaped core material is made of a laminate of fiber nonwoven webs. Thus, a hardened layer in which the fibers are heat-fixed with a binder is formed on at least one surface of the core material. This vacuum heat insulating material is arranged on the outer box side of the space formed by the outer box and the inner box so that the surface of the vacuum insulating material on the hardened layer side faces the inner surface of the outer box. By filling a foamed heat insulating material, a refrigerator excellent in heat insulation and appearance quality can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum heat insulating material which can be used as a heat insulating material such as a refrigerator, a heat and cold container, a vending machine, an electric water heater, a vehicle, and a house which require heat insulation.

[0002]

2. Description of the Related Art In recent years, energy saving has been strongly demanded from the viewpoint of preventing global warming, and energy saving has become an urgent issue for household electric appliances. In particular, a heat insulating material having excellent heat insulating performance is demanded from the viewpoint of efficiently utilizing heat in a heat insulating and cooling device such as a refrigerator, a freezer, and a vending machine.

As a general heat insulating material, a fiber material such as glass wool or a foamed material such as urethane foam is used. However, in order to improve the heat insulating property of these heat insulating materials, it is necessary to increase the thickness of the heat insulating material, and there is a limit to the space that can be filled with the heat insulating material, and when space saving or effective use of space is required. Cannot be applied.

Therefore, a vacuum heat insulating material has been proposed as a high performance heat insulating material. This is a heat insulating material in which a core material having a role of a spacer is inserted into an outer covering material having a gas barrier property, and the inside is reduced in pressure to be sealed. As a vacuum insulation material,
For example, as disclosed in Japanese Patent Application Laid-Open No. 9-138058, as the core material, a fibrous material such as glass wool which is solidified and molded using an organic binder can be used.

By the way, when the vacuum heat insulating material is applied to a heat insulating box such as a refrigerator, the foam heat insulating material formed by the outer and inner boxes is filled in the outer box side, the inner box side, or the outer side. It can be placed at any intermediate position between the box and the inner box, but actually it is placed on the outer box side. Specifically, a vacuum heat insulating material is often adhered to the inner surface of the outer box using an adhesive such as a double-sided tape or hot melt.

The reason why the vacuum heat insulating material is rarely arranged on the inner box side is that if it is arranged on the inner box side, the application area of the vacuum heat insulating material can be reduced, but the inner box is the outer box. It is easier to deform compared to the inner box and the outer surface of the inner box is uneven compared to the inner surface of the outer box, so it is difficult to firmly fix the vacuum heat insulating material to the outer surface of the inner box, and it is filled with foamed heat insulating material. This is because a cavity is likely to be formed between the vacuum heat insulating material and the inner box, and the inner box may be deformed due to the formation of the cavity or the heat insulating performance may be deteriorated.

The reason why the vacuum heat insulating material is rarely arranged at the intermediate position between the outer box and the inner box is that if the vacuum heat insulating material is arranged at the intermediate position between the outer box and the inner box, it will be close to the outer box or the inner box. There is an advantage that the vacuum heat insulating material can be applied to the surface with the existing objects such as the refrigerant pipe, the water distribution pipe, and the electric wiring buried in the foam heat insulating material, but the vacuum heat insulating material can be applied to the outer box and the inner box. Since it is fixed in the middle position, the number of parts increases and the workability is poor, and when the foam insulation is filled, the vacuum insulation and its fixing member only become a flow resistance of the foam insulation. Instead, since the flow of the foam insulation material is divided into the inner box side and the outer box side by the vacuum insulation material, it is difficult to reduce the wall thickness of the insulation box body, and the packing density of the foam insulation material varies. Cavities are easily formed, and the outer or inner box may be deformed or broken due to the formation of cavities. Performance there is a problem that is likely to decrease.

[0008]

However, when a fiber such as glass wool and a binder are used as the core material of the vacuum heat insulating material and the binder is dispersed throughout the glass fiber, the inside of the fiber molded body is evenly distributed. When the core material that is bound is used, the solid thermal conductivity of the core material increases, and the heat insulating performance of the vacuum heat insulating material deteriorates.

Further, since the exhaust resistance is increased during the production of the vacuum heat insulating material and the degree of vacuum inside the vacuum heat insulating material is less likely to decrease, the exhaust time becomes longer to obtain a predetermined heat insulating performance, and the productivity of the vacuum heat insulating material deteriorates. There was a problem of doing.

Further, in Japanese Patent Laid-Open No. 62-14725, a proposal has been made to use a hard urethane foam having an open cell structure as a core material. Since it is necessary to remove the high-density skin layer having closed cells formed on the surface of the foam block, the product yield is deteriorated, and there is a problem that it cannot be manufactured industrially at low cost.

On the other hand, when the vacuum heat insulating material is arranged on the inner surface of the outer box of the heat insulating box, the unevenness of the bonding surface of the vacuum heat insulating material tends to appear as the unevenness of the outer surface of the outer box. The appearance quality (plane accuracy) of the outer box, which is composed of a large flat surface, is severe and has a great impact on the commercial value.

Therefore, conventionally, in order to reduce the influence of the unevenness of the bonding surface of the vacuum heat insulating material on the outer box, the unevenness of the bonding surface of the vacuum heat insulating material is eliminated (the bonding surface of the vacuum heat insulating material and the outer box). Since a thicker adhesive layer is provided (so that no space is generated between the inner surface), a soft member that absorbs irregularities is interposed, and a vacuum heat insulating material with a large area for thickness tends to warp, I gave up on covering one plane with one vacuum heat insulating material, and unavoidably use multiple vacuum heat insulating materials,
A vacuum insulation material having high rigidity and high plane accuracy has been required in order to achieve a high level of compatibility between the outer box appearance quality (plane accuracy) and the heat insulation performance of the heat insulation box.

In view of the above, the present invention provides a vacuum heat insulating material which is capable of efficiently utilizing heat in a heat insulating and cooling device such as a refrigerator, a freezer, and a vending machine, and which is excellent in heat insulating performance, lightweight and excellent in productivity. The purpose is to provide. Another object of the present invention is to provide a vacuum heat insulating material having high rigidity and high plane accuracy. Another object of the present invention is to provide a refrigerator that is made of a heat-insulating box having high heat-insulating performance and that saves energy and has excellent appearance quality. It is another object of the present invention to provide a vacuum heat insulating material core material and a method for manufacturing the vacuum heat insulating material core material.

[0014]

In order to solve the above-mentioned problems, a vacuum heat insulating material of the present invention comprises a board-shaped core material and an outer covering material for enclosing the core material, and a vacuum in which the inside is depressurized and then sealed. A heat insulating material, wherein the board-shaped core material is composed of a laminated body of fiber nonwoven webs, and a cured layer in which the fibers are heat-fixed by a binder is formed on at least one surface of the core material ,
The board-shaped core material is packaged with the outer covering material.
The surface hardness as a vacuum heat insulating material is 50-80.
And characterized in that. Another vacuum insulation material of the present invention is
Consisting of a board-shaped core material and an outer covering material enclosing the core material,
It is a vacuum heat insulating material whose inside is depressurized and then sealed.
The core material is made of a laminate of non-woven fibrous webs.
Even if the above fibers are heat-fixed on one side surface with a binder
Hardened layer is formed, and the board-shaped core material is applied to the outer cover.
Table as a vacuum insulation after packaging by material
The surface hardness is in the range of 50-80 and the use of vacuum insulation
The vowel removed after breaking the outer cover material after use
The surface hardness of the core material should be in the range of 15-50.
Characterize .

By using the laminated material of the fibrous non-woven web, it is possible to obtain a vacuum heat insulating material having excellent heat insulating property in which the heat transfer between the respective layers of the fibrous non-woven web is hard to be performed, and the cured layer formed on the surface is used for handling. The good property and the good surface smoothness improve the stability during installation and the heat insulating property. On the other hand, a layer that is hardly cured is formed in the inner layer, so that the heat conductivity in the inner layer is lowered and the heat insulating effect is improved. In addition, because a non-woven fiber web is used,
A continuous open structure is formed in the entire core material, and due to this continuous open structure, the residual air between the jacket material and the molded body expands during depressurization in a decompression container, and the peripheral edge of the weld is broken and the jacket material is removed. Since it is possible to avoid the situation where the effect provided is lost, the quality is stabilized.

In the vacuum heat insulating material of the present invention, the density of the board-shaped core material is preferably in the range of 100 to 400 kg / m ³ . When the density is 100 kg / m ³ or more, the ratio of the materials forming the core material can be secured, so that it is possible to give practically sufficient strength, while the density is 4
When the amount is 00 kg / m ³ or less, the ratio of the core material in the heat insulating material can be suppressed to be low, so that the heat insulating property becomes good.

In the vacuum heat insulating material of the present invention, it is preferable that the board-shaped core material has a surface hardness of 15 to 70. If the surface hardness is 15 or more, the handling property and the surface smoothness can be secured, while the surface hardness is 70.
In the following cases, it becomes easy to dispose of the heat insulating material after the refrigerator or the like is discarded.

This surface hardness is developed by forming a hardened layer on the surface of the core material. In the hardened layer, the fibers are heat-fixed by the binder, that is, the fibers are bound by the binder. It is formed by The cured layer has a small void ratio and is formed by binding the fiber and the binder, and thus has high rigidity. Therefore, by forming the hardened layer on at least one surface (preferably both surfaces) of the core material, the rigidity of the core material is improved and the handleability is improved. In addition, since the hardness of the core material becomes high, the surface of the heat insulating material can be kept smooth without being dented or having large irregularities even after the outer covering is wrapped and the inside is vacuum-sealed. Therefore, the adhesiveness at the time of attachment to the refrigerating / cooling device is improved, and the heat insulating effect is further improved.

In the vacuum heat insulating material of the present invention, the binder is preferably made of an inorganic material. By using an inorganic material for the binder, the amount of gas generated from the binder over time is reduced, and the heat insulating performance over time of the vacuum heat insulating material is improved.

Further, it is more preferable that the binder is at least one compound selected from the group of compounds consisting of boric acid, borate, phosphoric acid, phosphoric acid salts and their heated products. Since these compounds form a glassy substance by themselves, it is easier to form a hardened layer, and particularly they have a good affinity with inorganic fibers and are unlikely to cause migration.

In the vacuum heat insulating material of the present invention, the cured layer may be formed by spraying water on the surface of the laminated body of the fibrous nonwoven web. This hardened layer is formed by simply spraying water on the surface of the fiber nonwoven web laminate, and binds the fibers with a substance (binder) that is eluted from the fibers by the attachment of water. In the method of spraying water, water does not completely penetrate to the inner layer and the inner layer has a weak binding strength, so that a softer core material can be obtained as the inner layer.

As the above-mentioned fibers, inorganic fibers are preferable,
Especially, glass wool or glass fiber is preferable.

Further, in the vacuum heat insulating material of the present invention, it is preferable that the outer covering material is a plastic-metal foil laminate film. The heat insulation effect is improved by coating the core material with a laminate film, and in particular, by using the metal foil as the inner layer and the plastic as the outer layer, excellent heat insulation performance with less heat conduction by the metal foil is obtained,
The attachment to the heat insulating box becomes easy and the affinity with the foam heat insulating material becomes high, so that the heat insulating effect is further improved.

Therefore, the vacuum heat insulating material of the present invention has a thermal conductivity of 0.0015 because it has the above-mentioned specific structure.
Is in the range of 0.0025 W / mK. This heat insulating performance is equivalent to 10 times that of conventional urethane heat insulating materials and 20 times that of glass wool, and is at an extremely high level.

Next, the refrigerating machine and the cold machine of the present invention have an outer box, an inner box, and a foam insulation material and a vacuum insulation material in a space formed by the outer box and the inner box. A refrigerating machine and a cold / warm machine in which a vacuum heat insulating material is arranged in the space, and the space other than the vacuum heat insulating material is filled with a foam heat insulating material, wherein the vacuum heat insulating material is the vacuum heat insulating material of the present invention. It is characterized by

A refrigerating machine having excellent heat insulation performance is provided by arranging a vacuum heat insulation material of the present invention having excellent heat insulation performance in a space consisting of an outer box and an inner box and filling a foam insulation material in the other space. And cold and warm equipment can be obtained.

Further, the refrigerator of the present invention has an outer box, an inner box, a foam heat insulating material and a vacuum heat insulating material in a space formed by the outer box and the inner box, and the vacuum heat insulating material A refrigerator which is arranged on the outer box side of a space and is filled with a foamed heat insulating material in the space other than the vacuum heat insulating material, wherein the vacuum heat insulating material is the vacuum heat insulating material of the present invention. The surface of the material on the side of the hardened layer faces the inner surface of the outer box.

The vacuum heat insulating material of the present invention has a lower binder concentration in the inner layer of the core material, and is lighter in weight than a conventional vacuum heat insulating material using a core material having a uniform binder concentration even inside the core material. Can be higher Further, the vacuum heat insulating material of the present invention has a high rigidity because the hardened layer is formed on the surface of the core material. In addition, the vacuum heat insulating material of the present invention can improve the flatness of the surface on the side of the hardened layer by compressing and heating with a press of a smooth mold to form the hardened layer on the core material. Further, since the vacuum heat insulating material of the present invention is lightweight, has high rigidity, and has high plane accuracy, it can be used in a wide area.

On the outer box side of the space consisting of the outer box and the inner box, a vacuum heat insulating material according to the present invention having a wide area is arranged with a large area, and a vacuum heat insulating material having high rigidity, high heat insulation performance and high plane accuracy is arranged. By filling the foam insulating material with the foamed heat insulating material, it is possible to achieve a high level of compatibility between the outer box appearance quality (planar accuracy) and the heat insulation performance of the heat insulating box body, and it is possible to obtain a refrigerator that is energy-saving and has excellent appearance quality.

Further, the refrigerator of the present invention includes an outer box and an inner box.
And foam in the space formed by the outer box and the inner box
A heat insulating material and a vacuum heat insulating material;
Placed on the side of the outer box between
A refrigerator having a foam insulation material filled between
The air-insulating material is a board-shaped core material, and a jacket material enclosing the core material.
It is a vacuum insulation material that consists of
The board-shaped core material is made of a laminate of fibrous non-woven webs.
The fiber on at least one surface of the core material.
To form a hardened layer that is heat set,
The hardened layer side surface of the material is arranged so as to face the inner surface of the outer box.
In addition, with respect to the portion where the refrigerant pipe is arranged on the inner surface of the outer box, the refrigerant pipe can be housed on the surface of the vacuum heat insulating material on the side of the hardened layer by pressing from the outside of the outer covering material. forming a groove, and wherein said that the refrigerant pipe is disposed the vacuum heat insulating material to fit in the groove. The vacuum heat insulating material of the present invention has a binder concentration in the inner layer of the core material which is softened to soften the inner layer of the core material. A groove can be formed in the groove. Then, even for the portion where the refrigerant pipe is arranged on the inner surface of the outer box, a large vacuum heat insulating material is arranged so as to cover the refrigerant pipe without arranging a plurality of small vacuum heat insulating materials while avoiding the refrigerant pipe. Therefore, it is possible to efficiently insulate the heat of the outer box and the refrigerant pipe from being transferred to the interior with a small number of vacuum heat insulating materials, and it is possible to obtain a refrigerator excellent in energy saving.

The vacuum heat insulating material of the present invention can be fixed to the outer box with an adhesive such as hot melt, and the thickness of the adhesive layer is preferably in the range of 70 to 130 μm. Providing a layer of adhesive having a thickness of more than 130 μm is a waste of the adhesive, and since the adhesive is more likely to transfer heat than the foamed heat insulating material, the heat insulating performance is deteriorated. If the thickness of the adhesive layer is less than 70 μm, the reliability of adhesion will be reduced.

The vacuum heat insulating material core material of the present invention is composed of a laminated body of fibrous non-woven webs, and a cured layer in which the fibers are thermally fixed by a binder is formed on at least one surface of the core material. It is characterized by

In general, depending on the binder, a hardened layer is formed only on the surface layer of the molded product, and a small amount of the binder that has penetrated into the inside is mostly transferred to the surface layer by migration, and a hardened layer is hardly formed inside. There is also. In this case, there is a concern that internal cracking may occur and the strength of the entire molded body may be reduced. However, for example, according to a method of forming a board in the form of a board and then applying a binder to the surface and compressing and heating the board to obtain a board-like molded body, in the surface layer, a layer having a high concentration of the applied binder cured is formed. A small amount of the binder that has permeated inside does not migrate so much and hardens inside the surface layer. As a result, it is possible to obtain a molded product having a different binder concentration in the thickness direction of the board and also a board-shaped molded product in which a small amount of the binder is hardened even inside the board and which has excellent strength.

Therefore, the method for manufacturing a vacuum insulation core material of the present invention comprises the steps of laminating fibers into a predetermined shape, and applying a binder aqueous solution or water to at least one outer surface of the laminated fiber web. A step of compressing the laminated fiber web coated with the binder at a temperature of 100 ° C. or lower;
Heating and compressing at a temperature of 0 ° C. or higher.

[0035]

BEST MODE FOR CARRYING OUT THE INVENTION The vacuum heat insulating material of the present invention is a vacuum heat insulating material comprising a board-shaped core material and an outer covering material for enclosing the core material, the interior of which is decompressed and hermetically sealed. The core material is made of a laminate of non-woven fiber webs, and a cured (solidified) layer in which the fibers are heat-fixed by a binder is formed on at least one surface of the core material. The board-shaped core material preferably has a surface hardness of 15 to 70, and this surface hardness represents the surface hardness of the core material before packaging with the outer covering material. Therefore, the surface hardness of the vacuum heat insulating material after packaging with the outer covering material is preferably 50 to 80, and more preferably 60 to 75.

The surface hardness of the core material taken out by breaking the jacket material after using the vacuum heat insulating material is 15
It is preferably in the range of 50 to 50, and more preferably in the range of 20 to 40. If the surface hardness is too low, the handling property may be poor, and the work efficiency in the disposal process may be reduced.On the other hand, considering the durability of the core material, the surface hardness is high even if there is some decrease in hardness. If it is too much, a process such as cutting off the cured (solidified) layer separately is required, which may complicate the process.

In the present invention, the hardness is defined as a value when the hardness of the surface of the core material is measured by a durometer, and the larger the numerical value is, the harder the hardness is, and the smaller the numerical value is, the softer the softness is.

In the vacuum heat insulating material of the present invention, since a hardening (solidifying) layer formed by binding the fibers with a binder is formed on at least one surface of the board-shaped core material, a hardening layer is formed. The binder concentration in the outer layer is different from that in the inner layer. More specifically, in the vacuum heat insulating material of the present invention, the binder concentration of the surface layer in the thickness direction of the board-shaped molded body is higher than that of the other layers. By increasing the binder concentration of the surface layer more than other layers, in addition to the above effects,
A core material having excellent surface smoothness can be obtained, and a vacuum heat insulating material having excellent appearance can be obtained.

Further, by providing a portion having a low binder concentration inside the portion other than the surface layer, it is possible to reduce the solid heat conduction inside, and the heat insulating performance is improved. further,
Exhaust resistance of the part where the binder concentration is small becomes small,
The degree of vacuum during evacuation can be easily lowered, and the productivity of the vacuum heat insulating material can be expected to improve. As described above, by using core materials having different binder concentrations in the thickness direction of the molded body, a vacuum heat insulating material having excellent core material rigidity, heat insulation performance, and productivity can be obtained.

The board-shaped core material in the present invention is not particularly limited as long as it is a board made of a fiber non-woven web laminate. The fibers constituting the core material may be either organic fibers or inorganic fibers as long as they can satisfy the characteristics of the board-shaped core material of the present invention. As the fiber, for example, glass wool, glass fiber, alumina fiber,
Inorganic fibers such as silica-alumina fibers, silica fibers, rock wool, silicon carbide fibers, or natural fibers such as cotton,
Examples thereof include organic fibers such as synthetic fibers such as polyester, nylon, and aramid, and known materials can be used. Inorganic fibers are desirable from the viewpoint of heat resistance during compression heating. Among them, glass wool and glass fiber are preferably used because they have high weather resistance and good water resistance. In particular, because of its excellent weather resistance and water resistance,
It is desirable to use glass containing boron as a material.

The fiber diameter used in the present invention is not particularly limited, but from the viewpoint of obtaining a lightweight core material capable of forming a continuous open structure and having high surface hardness. -20 μm, preferably 1-10 μm,
More preferably, it is 2 to 7 μm. Further, from the viewpoint of preventing peeling of the laminate, the average fiber length is 5 to 1
It is preferably 5 mm, but is not limited to this.

Powder may be added to the fibrous material as long as the characteristics of the board-shaped core material of the present invention are not impaired. Examples of the powder include inorganic powder such as silica, pearlite, and carbon black, and organic powder such as synthetic resin powder. Further, known materials such as pulverized products of foamed resin such as urethane foam, phenol foam and styrene foam can be appropriately used.

As the binder used in the present invention, an inorganic or organic binder can be used. In particular,
Colloidal silica, alumina sol, water glass, gypsum, boric acid or its salt, boron oxide, phosphoric acid or its salt, sodium silicate, an inorganic binder such as alkyl silicate, or phenol resin, urea resin, melamine resin, xylene resin, furan Examples thereof include thermosetting resins such as resins and epoxy resins, thermoplastic resins such as vinyl acetate and acrylic resins, and organic binders such as natural product adhesives. These may be used alone or as a mixture, or may be diluted with water or a known organic solvent before use. Above all,
Inorganic binders are preferred, especially boric acid, borates,
It is preferable to include at least one compound selected from phosphoric acid, phosphate, and heat products thereof.

Examples of the boric acid compounds include sodium borates such as boric acid, metaboric acid, boron oxide, sodium tetraborate hydrates or anhydrides, ammonium borate, lithium borate, borates. Examples thereof include magnesium acids, calcium borates, aluminum borates, zinc borates, perborates, alkylboric acids, boroxine derivatives and the like.

Examples of the phosphoric acid compounds include phosphoric acid, phosphorus oxide such as diphosphorus pentoxide, primary phosphate, secondary phosphate, tertiary phosphate, pyrophosphate, tripolyphosphate, Examples thereof include phosphates such as metaphosphates, their sodium salts, potassium salts, ammonium salts, magnesium salts, aluminum salts and the like.

Of these, glass-forming materials or water-soluble substances are preferred. For example, boric acid, metaboric acid, boron oxide, borax, phosphoric acid, aluminum monophosphate, sodium hexametaphosphate and the like.

When a board-shaped fiber molded body is prepared by using it as a binder for a molded body, it is used by mixing one or more of the above compounds, or by mixing other binders, or by diluting them. To do.

The method of attaching the binder to the core material is not particularly limited, but the binder or its diluent is applied or sprayed to be attached. Specifically, by molding the core material to some extent, spraying the binder, and then heat-compressing the molded product, a molded product having different binder concentrations in the thickness direction of the board-shaped molded product can be obtained.

When the fiber is made into a fiber, a binder or its diluting liquid is sprayed, and a fiber having a high binder concentration is arranged in a part of the board, and a fiber having a low binder concentration or a fiber having no binder is arranged in the other part. It is also possible to obtain a board having different binder concentrations in the thickness direction of the molded product by subsequently solidifying the fiber laminate by compression heating or the like. The use of the fiber laminate makes it difficult for heat to move between the layers, thereby improving the heat insulating property.

Further, without using the above binder,
Water may be sprayed on the surface of the fiber nonwoven web laminate, and the fibers may be bound by a substance (binder) that is eluted from the fibers by the attachment of water. In this case, since water does not completely penetrate to the inner layer and the inner layer has a weak binding strength,
A softer core material can be obtained as the inner layer.

Alternatively, a board-shaped molded body having a high binder concentration and a board-shaped molded body having a low binder concentration are used.
By combining more than one sheet, it is possible to obtain core materials having different concentrations in the thickness direction.

The binder concentration is preferably such that the solid content of the binder is 0.1 wt% or more and 20 wt% or less with respect to the core material. This is because when the amount of the binder increases, there is concern that the amount of gas generated from the binder and the solid thermal conductivity may increase, which may adversely affect the heat insulating performance of the vacuum heat insulating material. On the other hand, if the amount of binder is small, the solidification of the fiber laminate will be insufficient.

The binder concentration is preferably different in the thickness direction of the board-shaped molded product, but the effect of reducing solid thermal conductivity and exhaust resistance is given to a portion having a low binder concentration, and the rigidity of the board is given to a portion having a large binder concentration. You can give each effect. In particular, a board-shaped molded article having a high binder concentration in at least one surface layer or both surface layers of the board-shaped molded article is preferable, and thereby a surface property becomes good when used as a vacuum heat insulating material. After the binder is attached, the laminated molded body is compressed or heat-compressed to form a board.

In this case, it is desirable to press the board-shaped core material so that the density (density) of the board-shaped core material becomes 100 to 400 kg / m ^3, and the densities in the board may be different. Density hardly retain shape as the molded body and 100 kg / m ³ smaller because the insulating performance of the vacuum heat insulating material becomes large solid heat conductivity becomes greater than 400 kg / m ³ is considered to be worse . The density of the board is preferably 120-300 kg / m ³ ,
More preferably, it is in the range of 150 to 250 kg / m ³ .

The thermal conductivity of the board-shaped core material is in the range of 0.030 to 0.038 W / mK, preferably in the range of 0.033 to 0.037 W / mK at an average temperature of 24 ° C. Good to have. In addition, the board-shaped core material
Considering productivity and the like, it is desirable to have a certain degree of rigidity. The thickness of the core material (total thickness when two or more sheets are laminated) is not particularly limited, but is usually 5 to 20 mm.

The jacket material in the present invention is not particularly limited as long as it has at least a gas barrier layer and a heat fusion layer, and a surface protective layer or the like may be provided if necessary.

As the gas barrier layer, a metal foil, a metal, an inorganic oxide, a plastic film vapor-deposited with diamond-like carbon, or the like can be used. If it is used for the purpose of reducing gas permeation, It is not particularly limited.

As the metal foil, foils of aluminum, stainless steel, iron and the like can be used, but the foil is not particularly limited.

The material of the plastic film as the base material on which the metal or the like is vapor-deposited is not particularly limited, but polyethylene terephthalate, ethylene-vinyl alcohol copolymer resin, polyethylene naphthalate, nylon, polyamide, Deposition on polyimide or the like is preferable.

Materials for vapor deposition of metal on the plastic film are aluminum, cobalt, nickel, zinc,
Examples thereof include copper, silver, and a mixture thereof, but are not particularly limited.

The material for depositing the inorganic oxide on the plastic film may be silica, alumina or the like, but is not particularly limited.

As the heat-welding layer, a low-density polyethylene film, a chain low-density polyethylene film, a high-density polyethylene film, a polypropylene film, a polyacrylonitrile film, an unstretched polyethylene terephthalate film, an ethylene-vinyl alcohol copolymer film, Alternatively, a mixture thereof or the like can be used, but it is not particularly limited.

It is also possible to provide a surface protective layer on the outer surface of the gas barrier layer.

As the surface protective layer, a nylon film,
A polyethylene terephthalate film, a stretched product of a polypropylene film, or the like can be used. Further, if a nylon film or the like is provided on the outside, flexibility is improved, and bending resistance is improved.

The above film is laminated and used. Above all, a plastic-metal foil laminate film is preferably used. Alternatively, a metal container using a metal plate such as an iron plate, a stainless plate, or a zinc plate may be used as the outer covering material.

The bag shape of the outer covering material is not particularly limited, such as a four-sided sealed bag, a gusseted bag, a three-sided sealed bag, a pillow bag, and a center tape sealed bag. There is also a method of molding a metal plate into a rectangular parallelepiped and using it.

Further, in order to further improve the reliability of the vacuum heat insulator, a getter substance such as a gas adsorbent or a water adsorbent can be used.

In the production of the vacuum heat insulating material of the present invention, first, an outer covering material may be produced, and then a core material may be inserted into the outer covering material and the inside may be depressurized and sealed. A vacuum is created by installing a jacket material consisting of a core material and a roll-shaped or sheet-shaped laminated film, placing the roll-shaped or sheet-shaped jacket material along the core material, and then heat-sealing the jacket material. A heat insulating material may be produced, or a vacuum heat insulating material is manufactured by directly depressurizing the inside of the jacket material into which the core material is inserted to seal the opening of the jacket material, or a container formed of a metal plate. There is a method in which a board-shaped core material is inserted into the vacuum pump, the vacuum pump and the metal container are connected by a pipe to reduce the pressure inside the container, and then the pipe is sealed to obtain a vacuum heat insulating material, Not specified. Further, the board-shaped core material may be dried with water before insertion of the outer covering material, or an adsorbent may be inserted together when the outer covering material is inserted.

Since the vacuum heat insulating material of the present invention has the hardened layer formed on the surface thereof, a material having excellent surface smoothness can be obtained even after the pressure reduction treatment. The surface roughness is JIS B
It can be determined by 0601.

Further, the vacuum heat insulating material of the present invention is preferably used as a heat insulating material for a refrigerating machine or a cold machine. In that case, the foamed heat insulating material and the vacuum heat insulating material are arranged in a space formed by the outer box and the inner box of the refrigerating machine or the cold machine, but the vacuum heat insulating material is arranged in the space, and the vacuum heat insulating material is arranged. The space other than is filled with the foamed heat insulating material. For example, when applied to a refrigerator, a vacuum heat insulating material is attached to the outer box side or the inner box side of the space between the outer box and the inner box of the refrigerator and the other space is filled with resin foam, or the vacuum heat insulator and foam The method of use is specified, such as disposing a heat-insulating body integrally foamed with a resin body in the space between the outer box and the inner box of the refrigerator, using it in the same way as the door part, or using it as a partition plate. Although not a matter, it is preferable to use the vacuum heat insulating material between the machine room and the inner box or around the freezing room because the heat insulating efficiency is particularly excellent and the refrigerator can be operated with a low electric energy.

When a vacuum heat insulating material is attached to a refrigerating device such as a refrigerator or a cold temperature device, a hardened layer of the vacuum heat insulating material is used in order to prevent the formation of a cavity between the vacuum heat insulating material and the outer box to enhance the heat insulating effect. It is preferable that the side surface is fixed so as to face the inner surface of the outer box of the refrigerator. An adhesive such as a double-sided tape or hot melt can be used for fixing, but a hot melt adhesive is preferably used from the viewpoint of high reliability of adhesion.
The type of hot melt adhesive is not particularly limited, and examples thereof include those based on ethylene-vinyl acetate copolymer resin, polyamide resin, polyester resin, synthetic rubber and the like.

As the resin foam, for example, hard urethane foam, phenol foam or styrene foam can be used, but it is not particularly limited.

The foaming agent used for foaming the rigid urethane foam is not particularly limited, but cyclopentane, isopentane, n-pentane, isobutane are used from the viewpoint of ozone layer protection and global warming prevention. , N-butane, water (carbon dioxide gas foaming), an azo compound, argon and the like are preferable, and cyclopentane is particularly preferable from the viewpoint of heat insulating performance.

Further, the refrigerant used for the refrigerating machine / cooling machine is CFC 134a, isobutane, n-butane, propane, ammonia, carbon dioxide, water, etc., but it is not particularly specified.

In the present invention, the refrigerating machine and the cold machine are shown as representatives of machines that require heat insulation from the operating temperature range of −30 ° C. to room temperature, for example, a refrigerator and a refrigerator utilizing electronic cooling. Etc., such as automatic vending machines, which use cold / hot equipment that uses hot / cold heat up to a higher temperature range, and equipment that does not require power, such as gas equipment or cooler boxes.

Further, the vacuum heat insulating material of the present invention can be used for personal computers, jars, rice cookers and the like.

Next, a method of manufacturing the vacuum insulation core material of the present invention will be described. In the production method of the present invention, a step of laminating the fiber web into a predetermined shape, a step of applying a binder aqueous solution diluted with water (or water) to at least one outer surface of the laminated fiber web, and a binder Compressing the applied laminated fiber web at a temperature of 100 ° C. or lower;
Heating and compressing at a temperature of 0 ° C. or higher. The fibrous webs are laminated in a predetermined shape, and a binder aqueous solution (or water) diluted with water is applied to the outer surface of the laminated fibrous webs. At this time, the aqueous binder solution (or water) diluted with water is applied to one or both surfaces of the laminated fiber or an arbitrary outer surface such as the entire surface. afterwards,
The laminated fibrous web coated with the binder is compressed at a temperature of 100 ° C. or lower, and it is preferable to compress the laminated fiber web at room temperature so that water does not easily evaporate.

Here, the concentration of the aqueous binder solution cannot be unconditionally specified because it varies depending on the type of binder, the coating amount, and the addition amount, but is 0.5 to 20% by weight in consideration of the solubility in water. It is desirable to do. The coating amount of the binder aqueous solution is not particularly limited, but it is preferably used in a ratio of 50 parts by weight or more and 300 parts by weight or less with respect to 100 parts by weight of the fiber laminate. 50 used
When the amount is less than the weight part, the aqueous solution hardly penetrates into the fiber laminate, and when the amount is more than 300 parts by weight, the excess water flows out in the liquid state in the subsequent heating and compression step, and the binder flows out together with the water content. This is because loss will occur.

Thereafter, the laminated fiber is heated and compressed at a temperature of 100 ° C. or higher. The purpose of this is to evaporate the water content and to cure the binder, and it is preferable to heat the laminated fiber at the binder curing temperature or higher. The temperature is preferably 600 ° C. or lower from the viewpoint of preventing the binder from penetrating too much into the laminate during heating and compression and preventing the fibers from melting.

In general, when a molded product is prepared by using a fiber coated with a binder during fiberizing, it is easy to obtain a board having a uniform binder distribution in the molded product, and it is difficult to obtain a molded product having a concentration gradient. However, according to the production method of the present invention, fibers are laminated in a predetermined shape, a binder is applied to at least one surface of the laminated fibers, and the binder is compressed once at a temperature of 100 ° C. or lower, that is, moisture evaporation or lower. The surface layer has a high binder concentration and a low binder concentration inside, and then compressed and heated at a temperature of 100 ° C. or higher to evaporate water,
It is possible to obtain a core material in which the binder concentration is different in the thickness direction, and moreover, a small amount of binder is easily bound even inside the molded body, and the strength is excellent.

[0081]

EXAMPLES The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples.

(Embodiment 1) FIG. 1 is a sectional view of a vacuum heat insulating material in an embodiment of the present invention. Reference numeral 1 denotes a vacuum heat insulating material, which is a vacuum heat insulating material 1 in which a board-shaped core material 2 is inserted into an outer covering material 3 and the inside is reduced in pressure to be sealed.

First, the board-shaped core material 2 has an average fiber diameter of 5 μm.
m, an average fiber length of 10 mm, and a true specific gravity of 2.5 g / cm ³ of glass wool 4 were laminated to a predetermined density. The binder is 5 parts by weight of glass wool 100 parts by weight.
As the solution, 10 parts by weight of water glass was dissolved in 90 parts by weight of water to prepare 100 parts by weight of aqueous solution of water glass. This water glass aqueous solution is sprayed on both surfaces of the laminated glass wool 4 with a spraying device, and then pressed in a hot air circulation furnace at 450 ° C. for 20 minutes so that the density becomes 230 kg / m ^3, and a board-shaped core Material 2 was obtained. Board-shaped core material has a density of 2
The heat conductivity was 35 kg / m ³ , and the thermal conductivity was 0.35 W / mK.

A cross-sectional view of this board-shaped core material 2 is shown in FIG. It was confirmed that the binder 5 did not remain much in the board inner surface layer, and a large amount of the binder was hardened in the board outer layer, and a hardened layer was formed on the surface. The surface hardness of this core material was measured and found to be 65.

FIG. 11 shows the appearance of the surface of the board-shaped core material observed with an Olympus optical microscope BH-2 (magnification: 580 times). It can be seen that the crossed fibers are bound and hardened by the binder.

As the jacket material 2, two laminated films were formed into a bag by three-way sealing. One of the two laminated films is a linear low-density polyethylene film (hereinafter referred to as LLDPE) having a thickness of 50 μm as a heat-sealing layer,
As a gas barrier layer, an ethylene-vinyl alcohol copolymer film (hereinafter referred to as EVOH) having a thickness of 15 μm, which is formed by aluminum vapor deposition with a thickness of 450 Å, and a polyethylene terephthalate film having a thickness of 12 μm (hereinafter, referred to as PET) are 450 LLDP, which is a heat-sealing layer, made of a film obtained by sticking aluminum vapor-deposited surfaces to each other with a film formed by aluminum vapor deposition of Angstrom
E and EVOH of the gas barrier layer are dry-laminated. For the other one, the heat-sealing layer is LL having a thickness of 50 μm.
A DPE, a gas barrier layer having a thickness of 6 μm on the aluminum foil, a protective layer having a thickness of 12 μm nylon, and an outermost layer having a thickness of 12 μm are used.

The board-shaped core material 2 was dried in a drying oven at 140 ° C. for 1 hour, inserted into the jacket material 3, and the inside was depressurized to 3 Pa for 5 minutes and sealed.

The thermal conductivity of the vacuum heat insulating material 1 produced as described above is 0.0022 W / mK at an average temperature of 24 ° C.
And its surface hardness was 70.

In order to confirm the reliability over time, the deterioration of the heat insulating material was evaluated by an acceleration test, but the thermal conductivity under the condition of 10 years elapsed was 0.005 W / mK at an average temperature of 24 ° C. The outer coating material of the vacuum heat insulating material was broken, the core material was taken out, and the surface hardness was 60.

Example 2 A vacuum heat insulating material having the structure shown in FIG. 3 was produced. The board-shaped core material 2A was inserted into the outer covering material 3 and the inside was reduced in pressure to be sealed to obtain a vacuum heat insulating material. The board-shaped core material 2A has an average fiber diameter of 5 μm and an average fiber length of 1
Glass wool 4 having 0 mm and a true specific gravity of 2.5 g / cm ³ was laminated to a predetermined density. Binder 5A is boric acid 3 as a binder for 100 parts by weight of glass wool.
One part by weight was dissolved in 97 parts by weight of water and 100 parts by weight of an aqueous boric acid solution was used. This boric acid aqueous solution is sprayed on both surfaces of the laminated glass wool 4 with a spraying device,
It was pressed once at room temperature. Then, it was pressed for 20 minutes in a hot air circulation furnace at 350 ° C. so that the density was 230 kg / m ³ , to obtain a board-shaped core material 2A. This board-shaped core material has a density of 233 kg / m ³ and a thermal conductivity of 0.34 W /
It was mK.

A sectional view of the board-shaped core material 2A is shown in FIG. It was confirmed that the inner layer of the board was also bound by the binder although it was weaker than the outer layer, the amount of the binder increased toward the outer layer, and the hardened layer was formed on the surface.
The surface hardness of this core material was 45 as measured.

The board-shaped core material 2A was dried in a drying oven at 140 ° C. for 1 hour, inserted into the jacket material 3, and the inside was depressurized to 3 Pa for 5 minutes and sealed. In addition, as the outer covering material 3, the first embodiment is used.
The same outer covering material as used in 1. was used.

The thermal conductivity of the vacuum heat insulating material produced as described above was 0.002 W / mK at an average temperature of 24 ° C., and its surface hardness was 60.

Further, in order to confirm the reliability over time, deterioration of the heat insulating material was evaluated by an acceleration test, but the thermal conductivity under the condition of 10 years elapsed was 0.005 W / mK at an average temperature of 24 ° C. The core material was taken out by breaking the jacket material of the vacuum heat insulating material, and the surface hardness thereof was measured.

Compared with the vacuum heat insulating material obtained in Example 1, this vacuum heat insulating material uses boric acid as the binder and is pressed at room temperature before being heat-compressed. Remains, the crack did not occur inside the core material, and the strength was improved.

Example 3 A vacuum heat insulating material having the structure shown in FIG. 5 was produced. Insert the board-shaped core material 2B into the jacket material 3,
The inside was evacuated and sealed to obtain a vacuum heat insulating material. The board-shaped core material 2B is composed of three boards. Two of them (21B) have an average fiber diameter of 5 μm and an average fiber length of 10 m.
m and a true specific gravity of 2.5 g / cm ³ of glass wool 4 laminated to a predetermined density.
One part by weight was dissolved in 95 parts by weight of water, and 100 parts by weight of an aqueous boric acid solution was used. This boric acid aqueous solution is sprayed on both surfaces of the laminated glass wool 4 with a spraying device,
It was pressed once at room temperature. Then, it was pressed in a hot air circulation furnace at 350 ° C. for 20 minutes so that the density became 230 kg / m ³ . The other sheet (22B) has an average fiber diameter of 5μ.
Glass wool 4 having an average fiber length of 10 mm was compressed and heated at 350 ° C. to be used. It was confirmed that a hardened layer was formed on the surface of the board-shaped core material (21B) using the binder, and the surface hardness was 45.

A board (21B) using boric acid on the outer side and a board (22B) using only glass wool on the inner side were laminated on these three boards to form a board-shaped core material 2B.
A cross-sectional view of this board-shaped core material 2B is shown in FIG. As the outer covering material 3, the same outer covering material as that used in Example 1 was used. The density of this board-shaped core material is 190 kg / m ³ ,
The thermal conductivity was 0.34 W / mK.

The board-shaped core material 2B was dried in a drying oven at 140 ° C. for 1 hour, inserted into the jacket material 2, and the inside was depressurized to 3 Pa for 5 minutes and sealed.

Vacuum heat insulating material 1B produced as described above
Has a thermal conductivity of 0.0019 W / m at an average temperature of 24 ° C.
K, and the surface hardness was 60.

In order to confirm the reliability over time, the deterioration of the heat insulating material was evaluated by an acceleration test, but the thermal conductivity under the conditions of 10 years was 0.005 W / mK at an average temperature of 24 ° C. The core material was taken out by breaking the jacket material of the vacuum heat insulating material, and the surface hardness thereof was measured.

By using a board with a boric acid binder in the surface layer and a board made only of glass wool in the inner layer, it is possible to obtain a core material having a small solid thermal conductivity and excellent heat insulation performance because there is no binder in the inner layer. I was able to.

(Embodiment 4) FIG. 7 is a sectional view of a freezer-refrigerator according to an embodiment of the present invention, and FIG. 8 is an enlarged sectional view of a main part of a ceiling surface portion of a heat insulating box of the same refrigerator-freezer. 6 is a refrigerator,
Reference numeral 7 is a heat insulating box forming a refrigerator, and 1A is a vacuum heat insulating material. In this embodiment, the vacuum heat insulating material 1A is arranged on the outer box 8 side inside the box body so that the surface of the core material 2A on which the hardened layer is formed faces the inner surface of the outer box 8.

Further, in the present embodiment, the inner surface of the outer box 8 is pressed from the outside of the outer covering material 3 to the surface of the core material 2A on which the hardened layer is formed, with respect to the portion where the refrigerant pipe 21 is arranged. The vacuum heat insulating material 1A in which the groove 22 capable of accommodating the refrigerant pipe 21 is formed is arranged so that the refrigerant pipe 21 fits in the groove 22.

In this embodiment, the vacuum heat insulating material 1A is
Outer box 8 with thermoplastic gel-like hot melt adhesive 23
Fixed to. The layer of the adhesive 23 has a thickness of about 100 μm.
m, but it is preferably in the range of 70 to 130 μm. The adhesive 23 is uniformly applied to the surface of the vacuum heat insulating material 1A to be adhered to the outer box using a roller or the like without excess or deficiency.

The heat-insulating box body 7 has a vacuum heat-insulating material 1A disposed in advance inside the box body constituted by an outer box 8 formed by press-molding an iron plate and an inner box 9 vacuum-molding ABS resin through a flange. The space other than the vacuum heat insulating material 1A is foamed and filled with a hard urethane foam 10. The rigid urethane foam 10 uses cyclopentane as a foaming agent.

The heat insulating box 7 is divided by a partition plate 12, and an upper part is a refrigerating chamber 13 and a lower part is a freezing chamber 14. A damper 15 is attached to the partition plate 12.

Reference numeral 16 denotes an evaporator arranged in the refrigerator, which includes a compressor 18, a condenser 19 and a capillary tube 20.
And are sequentially connected in an annular shape to form a refrigeration cycle. Isobutane, which is a refrigerant, is enclosed in the refrigeration cycle.

The evaporator is divided into a refrigerating room 13 and a freezing room 14.
You may provide in a place and connect them in series and parallel, and you may form a refrigerating cycle.

Further, a door body 11 is attached to the refrigerator 6, a vacuum heat insulating material 1A is disposed inside the door body 11, and a space portion other than the vacuum heat insulating material is foamed and filled with a hard urethane foam 10. ing.

The vacuum heat insulating material 1A has the same structure as that shown in the second embodiment. When the power consumption of the thus constructed refrigerator was measured, it was 25% lower than that of a refrigerator not equipped with a vacuum heat insulating material, confirming the heat insulating effect.

Comparative Example 1 FIG. 9 is a sectional view of a vacuum heat insulating material in a comparative example of the present invention. Reference numeral 1a is a vacuum heat insulating material, and the board-shaped core material 2a is inserted into the outer covering material 3a, and the inside is reduced in pressure and sealed to form the vacuum heat insulating material 1a. The material composition of the outer covering material 3a is the same as that of the outer covering material 3 used in the first embodiment, and the outer covering material 3a is formed into a bag by a three-way seal.

The board-shaped core material 2a is made of glass wool 4a.
After fiberizing (the same as that used in Example 1), the binder 5a was sprayed so as to be uniformly attached to the fiber surface.
The binder solution is 100 parts by weight of glass wool,
As a binder, 10 parts by weight of a phenol resin was dissolved in 90 parts by weight of water to prepare 100 parts by weight of an aqueous phenol solution. The raw cotton with the binder was laminated so as to have a predetermined density, and then pressed in a hot air circulation furnace at 200 ° C. for 20 minutes so that the density became 230 kg / m ³ . The surface hardness of this board-shaped core material was measured to be 75.
Met. The density of this board-shaped core material is 240 kg.
/ M ³ , and the thermal conductivity was 0.32 W / mK.

The board-shaped core material 2a is dried in a drying oven at 140 ° C. for 1 hour, inserted into the outer covering material 2a, and the inside is 3 Pa.
Was vacuumed for 10 minutes and sealed. A cross-sectional view of the board-shaped core material 2a is shown in FIG.

The vacuum heat insulating material 1a produced as described above
Has a thermal conductivity of 0.003 W / mK at an average temperature of 24 ° C.
And its surface hardness was 80.

Further, the deterioration of the heat insulating material was evaluated by an acceleration test in order to confirm the reliability over time, but the thermal conductivity under the conditions of 10 years elapsed was 0.021 W / mK at an average temperature of 24 ° C. The outer coating material of the vacuum heat insulating material was broken, the core material was taken out, and the surface hardness was measured and found to be 75.

Compared with Example 1, since the phenol resin was used as the binder and the resin was uniformly cured in the board, both initial performance and aging performance deteriorate.

Comparative Example 2 FIG. 9 is a sectional view of a vacuum heat insulating material in a comparative example of the present invention. Reference numeral 1b is a vacuum heat insulating material, and the board-shaped core material 2b is inserted into the outer covering material 3b, and the inside is sealed by reducing the pressure to obtain a vacuum heat insulating material 1b. Outer material 3b
The material composition of was the same as that of the outer jacket material 3 used in Example 1, and the outer jacket material 3b was manufactured by bag making with a three-way seal.

The board-shaped core material 2b is made of glass wool 4b.
After fiberizing (same as that used in Example 2), it was sprayed so that the binder 5b was uniformly attached to the fiber surface.
As the binder, 3 parts by weight of boric acid was dissolved in 97 parts by weight of water as 100 parts by weight of glass wool, and 100 parts by weight of an aqueous boric acid solution was used. The raw cotton with the binder is laminated to have a predetermined density, and then the density is 230 kg / m in a hot air circulation furnace at 350 ° C.
^It was pressed for 20 minutes so as to be ³ .

The board-shaped core material 2b was dried in a drying oven at 140 ° C. for 1 hour, inserted into the outer covering material 2b, and the inside was 3 Pa.
Was vacuumed for 10 minutes and sealed. A cross-sectional view of the board-shaped core material 2b is shown in FIG. The density of this board-shaped core material is 2
It was 33 kg / m ³ , and the thermal conductivity was 0.34 W / mK. When the surface hardness of this board-shaped core material was measured, it was 4
It was 5.

The vacuum heat insulating material 1b produced as described above.
Has a thermal conductivity of 0.0025 W / m at an average temperature of 24 ° C.
K, and the surface hardness was 60.

In order to confirm the reliability over time, the deterioration of the heat insulating material was evaluated by an acceleration test, but the thermal conductivity under the conditions of 10 years was 0.015 W / mK at an average temperature of 24 ° C. The outer coating material of the vacuum heat insulating material was broken, the core material was taken out, and the surface hardness was 35.

As compared with Example 2, since the binder was uniformly hardened, the initial performance was deteriorated and a long exhaust time was required.

[0123]

As described above, according to the present invention,
It is possible to obtain a vacuum heat insulating material that is easy to mold, has excellent handling properties, has high surface hardness, excellent surface smoothness, and has a small solid thermal conductivity and excellent heat insulating properties.

Further, since the hardened layer formed by binding the fibers with the binder is formed on at least one surface of the vacuum heat insulating material core material, rigidity is imparted to the core material to facilitate handling, and The smoothness is improved, and the productivity at the time of manufacturing the vacuum heat insulating material is improved. In addition, since the concentration of the binder that binds the fibers in the thickness direction of the core material is higher in the surface layer than in the other layers, and a small portion is provided inside, the solid heat conduction inside is reduced and the heat insulation performance is reduced. improves. Further, the exhaust resistance of the portion where the binder concentration is low can be reduced, the vacuum degree at the time of exhaust can be easily lowered, and the productivity of the vacuum heat insulating material can be expected to be improved.

Further, according to the refrigerating machine and the cold / warm machine of the present invention, the vacuum heat insulating material of the present invention having excellent heat insulating performance is arranged in the space consisting of the outer box and the inner box, and the foam insulation is provided in the other spaces. By filling the material, it is possible to obtain a refrigerating machine and a cold machine having excellent heat insulation performance.

Further, according to the method for producing a core material for a vacuum heat insulating material of the present invention, the core material of the present invention in which the binder concentration is different in the thickness direction and a small amount of the binder is bound even inside the molded body is easily obtained, It is possible to obtain an excellent core material.

Also, according to the refrigerator of the present invention, the vacuum heat insulating material of the present invention which is lightweight, has high rigidity, has excellent heat insulating performance and has high plane accuracy is provided on the outer box side of the space formed by the outer box and the inner box. It is possible to achieve a high level of appearance quality (flatness accuracy) of the outer box and the insulation performance of the insulation box body by filling the other space with foam insulation material, which saves energy and provides excellent appearance quality. You can get a fridge.

Further, in the vacuum heat insulating material of the present invention, after the vacuum heat insulating material is manufactured, the grooves can be formed on the surface of the vacuum heat insulating material by pressing from the outer covering material. By arranging a vacuum heat insulating material having grooves formed in the refrigerant pipes in the installed portion, a refrigerator excellent in energy saving can be obtained by using a small number of vacuum heat insulating materials.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of a vacuum heat insulating material according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of a board-shaped core material according to an embodiment of the present invention.

FIG. 3 is a schematic sectional view of a vacuum heat insulating material according to an embodiment of the present invention.

FIG. 4 is a schematic cross-sectional view of a board-shaped core material according to an embodiment of the present invention.

FIG. 5 is a schematic sectional view of a vacuum heat insulating material according to an embodiment of the present invention.

FIG. 6 is a schematic cross-sectional view of a board-shaped core material according to an embodiment of the present invention.

FIG. 7 is a schematic sectional view of a refrigerator-freezer according to an embodiment of the present invention.

FIG. 8 is an enlarged cross-sectional view of a main part of a ceiling surface portion of a heat insulating box of a refrigerator-freezer.

FIG. 9 is a schematic sectional view of a vacuum heat insulating material in a comparative example of the present invention.

FIG. 10 is a schematic sectional view of a board-shaped core material in a comparative example of the present invention.

11 is an optical micrograph for observing the appearance of the surface of the board-shaped core material of Example 1. FIG.

[Explanation of symbols]

1 vacuum insulation 2 Board-shaped core material 3 jacket material 4 glass wool 5 binders 6 refrigerator 7 Insulated box 8 outer box 9 inner box 10 Rigid urethane foam 11 door body 12 partition boards 13 Refrigerator 14 Freezer 15 damper 16 evaporator 17 Machine room 18 compressor 19 condenser 20 capillary tubes 21 Refrigerant piping 22 groove 23 Hot melt adhesive

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) F16L 59/00-59/22 F25D 23/02-23/08

Claims (16)

(57) [Claims] 1. A vacuum heat insulating material comprising a board-shaped core material and an outer covering material enclosing the core material, the interior of which is depressurized and hermetically sealed, wherein the board-shaped core material is a laminated body of non-woven fibrous webs. from it, the fibers at least on one surface of the core material is heat-set hardened layer is formed by the binder, like the board
Vacuum break after packaging the core material with the outer coating material
A vacuum heat insulating material having a surface hardness of 50 to 80 as a heat material. 2. A vacuum heat insulating material comprising a board-shaped core material and an outer covering material for enclosing the core material, the interior of which is decompressed and hermetically sealed, wherein the board-shaped core material is a laminated body of non-woven fibrous webs. from it, the fibers at least on one surface of the core material is heat-set hardened layer is formed by the binder, like the board
Vacuum break after packaging the core material with the outer coating material
The surface hardness as a heat material is in the range of 50 to 80, and
After using the vacuum insulation material, remove it by breaking the outer covering material.
The surface hardness of the board-shaped core material taken out is in the range of 15 to 50.
A vacuum heat insulating material characterized by being enclosed . 3. The density of the board-shaped core material is 100 to 4
The vacuum heat insulating material according to claim 1 or 2 , having a range of 00 kg / m ³ . 4. The vacuum heat insulating material according to claim 1, wherein the binder is made of an inorganic material. 5. The binder is boric acid, borate,
The vacuum heat insulating material according to claim 4, wherein the vacuum heat insulating material is at least one compound selected from the group of compounds consisting of phosphoric acid, a phosphate, and a heated product thereof. 6. The vacuum heat insulating material according to claim 1, wherein the cured layer is formed by spraying water on the surface of the laminated body of the fibrous nonwoven web. 7. The vacuum heat insulating material according to claim 1, wherein the fiber is glass wool or glass fiber. 8. The vacuum heat insulating material according to claim 1, wherein the outer covering material is a plastic-metal foil laminate film. 9. The thermal conductivity is 0.0015 to 0.0025.
The vacuum heat insulating material according to any one of claims 1 to 8, which has a W / mK range. 10. An outer box, an inner box, and a foam heat insulating material and a vacuum heat insulating material in a space formed by the outer box and the inner box, wherein the vacuum heat insulating material is disposed in the space, and A refrigerating machine and a cold / warm machine in which the space other than the vacuum heat insulating material is filled with a foam heat insulating material, wherein the vacuum heat insulating material is used.
10. A refrigerating machine and a cold machine, which are the vacuum heat insulating material according to any one of 9 to 10. 11. An outer box, an inner box, and a foam heat insulating material and a vacuum heat insulating material in a space formed by the outer box and the inner box, wherein the vacuum heat insulating material is on the outer box side of the space. And a vacuum insulation material filled in the space other than the vacuum insulation material, wherein the vacuum insulation material is a refrigerator.
The vacuum heat insulating material according to any one of claims 9 to 11, wherein the surface of the vacuum heat insulating material on the side of the cured layer faces the inner surface of the outer box. 12. An outer box, an inner box, the outer box and the inner box
Foam insulation and vacuum insulation in the space formed by
And having the vacuum heat insulating material on the outer box side of the space
And fill the space other than the vacuum insulation with foam insulation
In the refrigerator, the vacuum heat insulating material has a board shape.
It consists of a core material and a jacket material that encloses the core material
A vacuum heat insulating material that is sealed after being pressed, wherein the board-shaped core material is
At least the core material is made of a laminate of non-woven fibrous webs.
The fibers are heat-fixed on one side with a binder
Is formed on the surface of the vacuum heat insulating material on the side of the hardened layer.
While being arranged to face the inner surface of the outer box, for the portion where the refrigerant pipe in the inner surface of the outer box is arranged ,
The vacuum heat insulating material wherein said outer form a receiving groove capable of the refrigerant pipe by press from the outside of the covering material on the surface of the hardened layer side of the vacuum heat insulating material so that the refrigerant pipe fits in the groove < br /> Refrigerator placed. 13. The refrigerator according to claim 11, wherein the vacuum heat insulating material is fixed to the outer box with an adhesive. 14. The refrigerator according to claim 13, wherein the adhesive is hot melt. 15. The thickness of the adhesive layer between the vacuum heat insulating material and the outer box is 70 to 130 μm.
The refrigerator according to 3 or 14. 16. A step of laminating fibers into a predetermined shape, a step of applying an aqueous binder solution or water to at least one outer surface of the laminated fiber web, and a step of applying the binder-coated laminated fiber web to 100 ° C. or less. A method for producing a vacuum insulation material core material, comprising: a step of compressing at a temperature; and a step of heating and compressing a compressed laminated fiber web at a temperature of 100 ° C. or higher.