KR20140013888A - Vacuum insulation material, refrigerator, equipment using vacuum insulation material - Google Patents

Abstract

The purpose of the present invention is to provide a vacuum insulation material and a refrigerator with improved insulation performance. The vacuum insulation material to solve problems includes a core material (51) of a fiber assembly and an outer cover material (53) having gas barrier properties of covering the core material (51). Compressive strength (mm/(kg/mg^2)) that the thickness (mm), when a predetermined load is applied to the fiber assembly, is divided by the weight (kg/m^2) per 1 m^2 of the fiber assembly is more than or equal to 23. [Reference numerals] (AA) Thickness direction; (BB) Plane direction

Description

Vacuum Insulator, Refrigerator, Equipment with Vacuum Insulation {VACUUM INSULATION MATERIAL, REFRIGERATOR, EQUIPMENT USING VACUUM INSULATION MATERIAL}

The present invention relates to an apparatus using a vacuum insulator, a refrigerator, and a vacuum insulator.

In recent years, from the viewpoint of global environmental protection and energy saving, improvement of thermal insulation of home appliances and industrial equipment has been considered. As a heat insulating material which insulates an apparatus, resin foam, organic, and inorganic fiber are used, but when it is going to improve heat insulation, it is necessary to thicken the thickness of a heat insulating material. If the thickness of the heat insulating material is thicker, the volume of the entire apparatus increases, and if the volume is not changed, the ratio of the space for mounting parts and the like is lowered. Accordingly, a vacuum insulator having excellent heat insulating properties than a resin foam or an inorganic fiber has been proposed. The vacuum insulator is made of a bag having a gas barrier property in the shape of a bag, a core material made of a fiber aggregate and a gas adsorption getter agent therein, the inside of the bag is decompressed, and the end of the bag is sealed. do. Compared with conventional heat insulating materials, such as resin foam and inorganic fiber, since it has 20-40 times of heat insulation, even if thickness of a heat insulating material is made thin, sufficient heat insulation can be performed.

Moreover, the examination for improving the heat insulation of a vacuum heat insulating material, and improving a functionality is performed variously.

As background art of this technical field, Unexamined-Japanese-Patent No. 2006-38122 (patent document 1) and Unexamined-Japanese-Patent No. 2011-236953 (patent document 2).

Patent document 1 consists of a core material, a moisture adsorption agent, and the outer cover material which has the gas barrier property which coat | covers the said core material and the said moisture adsorption agent, The said core material is glass short fiber of an average fiber diameter of 3-5 micrometers A vacuum insulator molded into a board shape by heat-pressing at 450 ° C. for 5 minutes lower than the melting point of is described.

Patent Literature 2 discloses a "core material having an average of 3 mm or more and 8 mm or less while having a fiber diameter of an inorganic or organic fiber laminate, and having an average fiber length of 2 mm or more and 10 mm or less, and a gas barrier property covering the core material. A vacuum insulator having a film, wherein the vacuum insulator has a porosity of 80% or more and 85% or less in an extension direction cross section in its broadening direction, and a porosity of a thickness direction cross section in the heat insulation direction of 85% or more and less than 100%. Vacuum insulator to be used ”.

Japanese Patent Application Laid-Open No. 2006-38122 Japanese Patent Application Laid-Open No. 2011-236953

However, the vacuum heat insulating material of patent document 1 uses the heat press method, and the fiber diameter of glass wool is 3-5 micrometers, and fiber is easy to melt | dissolve.

In addition, the pressure by the press acts on the contact point between the fibers, whereby the fibers are welded together.

Moreover, since the welded part becomes a heat path which propagates heat in a heat insulating material, the thermal conductivity of a vacuum heat insulating material will fall.

Thus, the fiber which comprises the core material used for the conventional vacuum heat insulating material becomes a problem of the propagation of the heat which arises by welding, and the propagation of the heat which arises by breaking of a fiber, ie, the deterioration of the thermal conductivity in a vacuum heat insulating material.

Moreover, the vacuum heat insulating material of patent document 2 is a core material in which fiber length is formed in 2 mm-10 mm on average, and fiber length is short. Therefore, it is difficult to control the orientation of the fiber, and the ratio of the fiber existing along the thickness direction from the plane on one side to the plane on the other side becomes high. Then, with the fiber along this thickness direction, heat becomes easy to be transmitted from the plane of one side to the plane of the other side, and as a result, heat conductivity becomes high.

Accordingly, an object of the present invention is to provide a vacuum insulator and a refrigerator having improved thermal insulation performance.

In order to solve the above problems, for example, the configuration described in claims is adopted. The present application includes a plurality of means for solving the above problems. For example, in the vacuum insulator provided with a core member of a fiber assembly and an outer cover material having a gas barrier property covering the core member, a predetermined load is applied to the fiber assembly. The compressive strength (mm / (kg / m < 2 >)), which is a value obtained by dividing the thickness (mm) by 1 by the weight (= basis weight) (kg / m < 2 >) of the fiber aggregate, is 23 or more.

Moreover, in the vacuum heat insulating material which has the core material of a fiber laminated body and the outer cover material which covers the said core material, when it is set as the average D of the fiber diameter of the said fiber laminated body, and the average L of fiber length, D is 4.5 micrometers or more, and L The aspect value obtained by / D is 48000 or more, It is characterized by the above-mentioned.

According to this invention, the vacuum heat insulating material and the refrigerator which improved the heat insulation performance can be provided.

1 is a front view showing a refrigerator according to the present embodiment.
2 is a sectional view taken along the line AA in Fig.
3 is a perspective view showing a vacuum insulator.
4 is a cross-sectional view taken along line CC of FIG. 3.
5 A diagram for describing a method for producing glass fiber.
6 is a front view showing a heat pump water heater according to the present embodiment.
7 is a view of a measurement result table of Examples 1 to 2 and Comparative Examples 1 to 2 of the present invention.
8 is a diagram illustrating wrinkles generation of an outer cover material in a comparative example.
It is a figure explaining the suppression of wrinkles of an outer cover material in an Example.
9B is an explanatory diagram illustrating the passage of time from the state of FIG. 9A.
10 is a view of a measurement result table of Examples 1-2 and Comparative Examples 1-2 of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Configuration of the refrigerator 1)

1 is a front view illustrating the refrigerator 1 according to the embodiment. 2 is a sectional view taken along the line A-A in Fig.

The refrigerator 1 of embodiment is the refrigerating chamber 2 which cools to a refrigerating temperature from the top, the ice-making (storage) chamber 3a which stores ice-making ice, and the upper freezer compartment (switching chamber or rapid supply cooling by freezing temperature). (Freezer compartment) 3b, the lower freezer compartment 4, and the vegetable compartment 5 which accommodates vegetables.

The refrigerating chamber doors 6a and 6b, the deicing (sealing) door 7a, the upper freezing door 7b, the lower freezing door 8 and the vegetable door 9 are respectively a refrigerating chamber 2, an ice making chamber 3a, The front opening part of each chamber front of the upper freezer compartment 3b, the lower freezer compartment 4, and the vegetable compartment 5 is opened and closed. In each door, the foam heat insulating material 23 and the vacuum heat insulating material 50 are arrange | positioned.

The refrigerating chamber doors 6a and 6b shown in FIG. 1 are the doors which rotate around the hinge 10 etc., and other ice making doors 7a, the upper freezing chamber door 7b, the lower freezing chamber door 8, The vegetable room doors 9 are all pull-out doors.

When the withdrawal type ice making door 7a, the upper freezing chamber door 7b, the lower freezing chamber door 8 and the vegetable chamber 9 are taken out, the containers constituting the chambers are taken out together with the doors.

In each of the refrigerating chamber doors 6a and 6b, the ice making door 7a, the upper freezing chamber door 7b, the lower freezing chamber door 8, and the vegetable chamber door 9, a space between the refrigerator main body 1H (see FIG. 2) is provided. A packing (not shown) for sealing is attached to the outer periphery of the refrigerator main body 1H side.

The partition heat insulation wall 12 for partitioning and insulating each is arrange | positioned between the refrigerating chamber 2 of a refrigerating temperature, the ice making (storing) chamber 3a of a refrigerating temperature, and the upper end freezing chamber 3b. The partition heat insulating wall 12 is a heat insulating wall having a thickness of about 30 to 50 mm, and each of these is used alone or in combination of a plurality of heat insulating materials such as styrofoam, foamed heat insulating material (hard urethane foam), and vacuum heat insulating material.

Between the ice making chamber 3a, the upper freezing chamber 3b, and the lower freezing chamber 4, because the same freezing temperature range and the temperature difference are the same or small, the partition which formed the packing receiving surface, not the partition insulating wall which divides and insulates. The member 13 is provided.

Between the lower end freezing chamber 4 of a freezing temperature, and the vegetable chamber 5 of a vegetable storage temperature, the partition heat insulation wall 14 for partitioning and insulating each is provided. The partition heat insulation wall 14 is a heat insulation wall about 30-50 mm like the partition heat insulation wall 12, and is similarly made of styrofoam, a foam insulation (hard urethane foam), a vacuum insulation, etc. As described above, the partition insulation walls 12 and 14 having heat insulation are provided in the partition of the storage compartment in which the storage temperature ranges of the refrigerating temperature and the freezing temperature are different.

The partition heat insulation walls 12 and 14 may be comprised using foamed polystyrene 33 and the vacuum heat insulating material 50b, as shown in FIG. 2, and are not specifically limited.

Moreover, as shown in FIG. 1, inside the refrigerator main body 1H, the storage compartment of the refrigerating compartment 2, the ice-making compartment 3a, the upper freezer compartment 3b, the lower freezer compartment 4, and the vegetable compartment 5 is shown from the top. Although partitions are formed respectively, the arrangement of the storage compartments is not particularly limited thereto. In addition, the refrigerating chamber doors 6a and 6b, the ice making door 7a, the upper freezing chamber door 7b, the lower freezing chamber door 8, and the vegetable door 9 also open and close by rotation, opening and closing by drawing out and dividing the door. The number is not particularly limited.

The refrigerator main body 1H shown in FIG. 2 includes an outer case 21 made of steel sheet such as PCM (Pre-Coated-Metal) steel sheet, and an inner resin case 22 made of resin such as ABS (Acrylonitrile Butadiene Styrene) resin. have. The inner case 22 forms a refrigerating chamber 2, an ice making chamber 3a and an upper freezing chamber 3b, a lower freezing chamber 4, and a vegetable chamber 5.

The space formed between the outer case 21 and the inner case 22 is provided with a heat insulation portion as the heat insulation space 1s, and insulates each storage compartment and the external space in the refrigerator main body 1H.

The vacuum heat insulating material 50 is arrange | positioned in the heat insulating space 1s between this outer case 21 and the inner case 22, and foam heat insulating materials, such as a hard urethane foam, in the heat insulating space 1s other than the vacuum heat insulating material 50. (23) is charging. Although the vacuum insulation material 50 is mentioned later, it is fixedly supported by the outer case 21 or the inner case 22 with the fixing member, support member, etc. which are not shown in figure, or it is attached to the outer case 21 or the inner case 22 with an adhesive agent. It is fixed.

Furthermore, in order to cool each room | chamber of the refrigerating chamber 2, the ice-making chamber 3a, the upper freezer chamber 3b, the lower freezer chamber 4, the vegetable chamber 5, etc. to predetermined | prescribed temperature, the ice-making chamber 3a and the lower freezer compartment ( On the back side of 4), the cooler 28 (refer FIG. 2) is provided.

The cooler 28, the compressor 30, the condenser 31, and a capillary tube (not shown) are connected to each other to form a refrigeration cycle.

Above the cooler 28, the blower 27 which circulates the inside of the refrigerator 1 by cooling the cold air cooled by the cooler 28, and arrange | positions it is arrange | positioned.

Moreover, in the rear part of the upper surface 1H1 of the refrigerator main body 1H shown in FIG. 2, the recessed part 40 for accommodating the power supply board etc. in which the electrical component 41 was mounted is formed. The control means such as a power supply board on which the electric parts 41 are mounted controls the various cooling operations of the refrigerator 1 and the driving / stop of various functions. Moreover, the cover 42 which covers the electrical component 41 is provided above the recessed part 40. The height of the cover 42 is arrange | positioned so that it may become substantially the same height as the upper surface 1H1 of the refrigerator main body 1H in consideration of external appearance design, ensuring the volume resistance of the refrigerator 1, and heat resistance. . Although it does not specifically limit, When the height of the cover 42 protrudes outward from the upper surface 1H1 of the refrigerator main body 1H, it is preferable to enter into the range within 10 mm.

Thereby, since the recessed part 40 is arrange | positioned in the recessed state as much as the recessed part 40 of the space which accommodates the electrical component 41 in the foam heat insulating material 23 side (high-inside side), it is possible to increase the heat insulation thickness. If it is to be secured, it protrudes toward the inside of the refrigerator, and inevitably satisfies the contents of the refrigerator 1. On the other hand, when the content of the refrigerator 1 is made larger, the thickness of the foamed heat insulating material 23 between the recess 40 and the inner case 22 becomes thinner. For this reason, as shown in FIG. 2, the vacuum heat insulating material 50a is arrange | positioned in the foam heat insulating material 23 which opposes the recessed part 40, and ensures and strengthens heat insulation performance. In this embodiment, the vacuum heat insulating material 50a is made into the one vacuum heat insulating material 50a shape | molded in substantially Z shape so that it may be over the case and the electric component 41 of an internal lamp which are not shown in figure.

In addition, since the compressor 30 and the condenser 31 which are arrange | positioned in the machine room of the back lower part (lower right of the refrigerator main body 1H of FIG. 2) of the refrigerator main body 1H shown in FIG. In order to prevent heat penetration into the inner case 22 inside, a vacuum insulator 50c is disposed on the projection surface of the compressor 30 or the condenser 31 toward the inner case 22 side. In addition, although the vacuum heat insulating material 50 is divided into several in FIG. 2, the structure which interrupts the thermal movement between the front of a machine room and the back of the vegetable chamber 5 by bending a plurality of single vacuum heat insulating materials 50c in the place. You may make it. In this case, the heat transfer through the shell material (detailed later) of the vacuum heat insulating material 50, what is called a heat bridge phenomenon, is suppressed, and heat insulation performance improves.

(Basic Configuration of Vacuum Insulation Material 50)

Next, the structure of the vacuum heat insulating material 50 (50a, 50b, 50c) is demonstrated using FIG. 3, FIG. 3 is a perspective view showing a vacuum insulator. 4 is a cross-sectional view taken along the line C-C of FIG.

The vacuum insulator 50 includes a core material 51 for forming a vacuum space, an inner packing material 52 for holding the core material 51 in a compressed state, and an adsorbent 54 for adsorbing moisture, gas, and the like. And an outer cover material 53 having a gas barrier layer covering the core material 51 held in a compressed state by the inner packing material 52. In addition, in FIG. 4, the adsorbent 54 is emphasized and shown.

The outer cover material 53 is arrange | positioned at the both sides outer side of the vacuum heat insulating material 50, and is comprised in the bag shape which bonded together the part of constant width from the outer edge of the laminated film of the equal size by heat welding. In addition, the bonding point 50h is prevented from forming a heat bridge by bending to the center side.

About the core material 51 of the vacuum heat insulating material 50, the glass wool of the following Example uses the average fiber diameter as a laminated body of the inorganic fiber which is not adhere | attached or bound with a binder etc.

The core material 51 is advantageous in thermal insulation performance because the outgas (the generation of gas) is reduced by using a laminate of inorganic fiber materials. However, the core material 51 is not particularly limited thereto. Inorganic fibers such as wool, glass wool, glass fiber, alumina, silica alumina, silica, rock wool, silicon carbide, and the like. Depending on the type of core material 51, the inclusion material 52 may be unnecessary.

In addition, for the core material 51, an organic resin fiber material can be used in addition to the inorganic fiber material. In the case of organic resin fiber, if the performance as the core material 51, such as heat resistance temperature, is cleared, it will not restrict | limit especially in use. Specifically, polystyrene, polyethylene terephthalate, polypropylene, and the like are fiberized so as to have a fiber diameter of the following examples by a melt blown method, a spunbond method, and the like, but are not particularly limited as long as they are organic resins or fiberization methods that can be fiberized.

It is preferable that a fiber aggregate consists of inorganic fiber or organic fiber, and is low in bulk density, and the compressive strength of a fiber aggregate is measured as follows. The fiber assembly is cut into a predetermined size (100 mm x 100 mm) and a load is applied to 25 g per 100 mm 2. After measuring the thickness (unit: mm) of the fiber aggregate in the weighted state, the value obtained by dividing the basis weight (weight per square meter of the fiber aggregate, unit: kg / m 2) by the compressive strength (unit: mm / (kg / m 2) )). The higher the compressive strength, the greater the resistance to weighting and the core material suitable for shape retention. In addition, as a method of bonding the fibers to each other, there is a use of a binder agent, a hot press, and the like. When these methods are used, the fibers are bonded to each other to increase the compressive strength. It is not preferable because the thermal conductivity deteriorates.

In the measuring method of the fiber diameter, the fiber was spun to obtain a fiber aggregate, which was enlarged under a microscope to an average value of 30 measured values.

Moreover, in this Example, there exists a method of performing a magnification measurement by a microscope, and the measuring method by a microneedle measuring machine. A microneedle measuring instrument is an instrument which measures fiber fineness, such as cotton, and measures fiber fineness by measuring the resistance with respect to the airflow of a certain amount of fiber masses. Specifically, the fiber of a certain weight is accommodated in a sample holder so that a fixed volume, and air of a fixed pressure is blown. Then, the fiber diameter is measured in µ order by reading the air flow rate at that time.

Although thinner is more preferable about a fiber diameter, it is preferable that it is 10 micrometers or less in consideration of environmental considerations and industrial productivity, and it is more preferable that it is 5.2 micrometers or less.

The laminate configuration of the outer cover material 53 is not particularly limited as long as it has gas barrier properties and can be thermally welded. In this embodiment, the surface (protective) layer, the first gas barrier layer, the second gas barrier layer, It is set as the laminated film which consists of a four-layered constitution of a heat welding layer.

The surface layer is a resin film having a role of a protective material, the first gas barrier layer is provided with a metal deposition layer on the resin film, the second gas barrier layer is provided with a metal deposition layer on the resin film having high oxygen barrier property, The first gas barrier layer and the second gas barrier layer are bonded so that the metal vapor deposition layers face each other. About the heat welding layer, the film with low hygroscopicity was used like a surface layer.

Specifically, the outer shell material 53 is a biaxially stretched polyethylene tere with a surface layer of biaxially stretched polypropylene, polyamide, polyethylene terephthalate or the like, and a first gas barrier layer with aluminum vapor deposition. A phthalate film and a 2nd gas barrier layer are made into the biaxially stretched ethylene vinyl alcohol copolymer resin film with aluminum vapor deposition, or the biaxially stretched polyvinyl alcohol resin film with aluminum vapor deposition, or aluminum foil, and a heat welding layer is an unstretched type It was set as each film, such as polyethylene and polypropylene.

About the laminated constitution and material of this laminated film of 4-layer structure, it is not specifically limited to these. For example, as a 1st and 2nd gas barrier layer, the metal foil or resin film provided with the gas barrier film by resin gas barrier coating materials, such as inorganic layer compound, polyacrylic acid, DLC (diamond-like carbon), etc., and heat-welding As the layer, for example, a polybutylene terephthalate film having a high oxygen barrier property or the like may be used. Although it is a protective material of a 1st gas barrier layer with respect to a surface layer, in order to improve the vacuum exhaust efficiency in the manufacturing process of the vacuum heat insulating material 50, it is preferable to arrange | position resin with low hygroscopicity.

In addition, since resin-based films other than metal foil normally used for a 2nd gas barrier layer deteriorate gas barrier property significantly by moisture absorption, deterioration of gas barrier property is arrange | positioned by arrange | positioning resin with low hygroscopicity also about a heat welding layer. While suppressing, the moisture absorption amount of the whole laminate film is suppressed. As a result, even in the vacuum evacuation step of the vacuum insulator 50 described above, since the amount of moisture contained in the envelope 53 can be reduced, the vacuum evacuation efficiency is greatly improved, leading to high performance of the insulation performance.

In addition, although the lamination (bonding) of each film is generally bonded by the dry lamination method via the two-component curable urethane adhesive hardened by two-component reaction heat, it is not specifically limited to the kind of bonding agent and the bonding method in this. Or by other methods such as a wet lamination method or a thermal lamination method.

In addition, although the polyethylene film which can be heat-welded was used for the wrapping material 52 in this embodiment, and the synthetic zeolite of the physical adsorption type was used for the adsorbent 54, all are not limited to these materials. The inner packaging material 52 can be heat-welded with low hygroscopicity, such as a polypropylene film, a polyethylene terephthalate film, and a polybutylene terephthalate film, and should just be a thing with few outgases.

As for the adsorbent 54, it adsorbs water and gas, and it becomes both physical adsorption and chemical reaction type adsorption, and silica gel, calcium oxide, synthetic zeolite, activated carbon, potassium hydroxide, sodium hydroxide, lithium hydroxide, etc. can be used.

(Manufacturing method of fiber aggregate (glass fiber))

As a core material 51 used for the vacuum heat insulating material 50, the case where glass wool of a fiber assembly is used is demonstrated. The glass wool is not cured by a binder bond or a heat press, is not hardened into a board shape, is flexible, and is packaged with a wrapping material 52 (for example, high density polyethylene) in a state having resilience to the compression direction. Degassing The core material 51 pressurized and compressed by the inner packing material 52 is inserted into the bag-shaped outer packing material 53 and opened, and the vacuum packing material is then vacuum-packed together with the inner packing material 52 and the inside of the outer packing material 53. It is formed as 50. Borosilicate glass is used for the glass which forms glass wool.

5 is a figure explaining the manufacturing method of glass fiber. The molten glass G is thrown in from the nozzle 101 connected to the glass melting furnace 100 toward the bottom of the hollow cylindrical rotating body (spinner) 100. The hollow cylindrical rotor 100 rotates at a high speed around the rotary shaft 103, and the injected molten glass G rises at the side wall of the rotor 100 by the action of centrifugal force. And molten glass G is blown out from the pore 105 formed in multiple at the side wall of the rotating body 100. The blown molten glass G is heated by the heating means 102 (flame spinning means, such as a burner), which heats in the arrow H direction. Here, the arrow H direction is a direction along the up-down direction of the some pore 105 provided in the side wall of the rotor 100.

Moreover, the gas discharge means 104 which discharges a gas by arrange | positioning it continuously or spaced concentrically around the side wall of the rotating body 100 on the outer periphery of the discharge port (near arrowhead of arrow H) of the heating means 102 Has

In this structure, the molten glass G discharged | emitted from the some pore 105 to the exterior of the rotating body 100 is formed in fibrous fiber. The fiber is guided in the heating direction H of the heating means 102 and made thinner, and proceeds downward, and the length of the fiber and the fiber are caused by the gas in the arrow F direction discharged from the gas discharging means 104. The density of an aggregate is adjusted.

The glass fibers thus spun are laminated so as to have a uniform density by a collecting device (not shown). However, as the cumulative time of spinning becomes longer, the pores 105 of the rotating body 100 gradually increase due to friction or the like. Therefore, the fiber diameter also tends to increase gradually.

The larger the fiber diameter, the easier the individual thermal conduction becomes and the smaller the thermal conduction resistance becomes. And when this fiber is applied as a vacuum heat insulating material, it will tend to worsen as heat insulation performance.

In order to prevent this deterioration of heat insulation performance, when the pore 105 of the rotating body 100 reaches a certain size, the new rotating body 100 may be replaced, but the rotating body 100 is frequently replaced in a short period of time. This is not preferable because the price is high and productivity is impaired.

Here, in the vacuum heat insulating material 50, the porosity which is the ratio which the said space occupies among the space which becomes the vacuum state other than the core material 51 and the core material 51 inside the wrapping material 52 in the cross section of the vacuum heat insulating material 50 here. The measuring method of is shown below.

First, the glass wool fiber prepared by the predetermined fiber diameter and fiber length was produced, and the vacuum insulation material 50 for porosity measurement (core material size 20x20x10t (mm)) which used them as a core material (core material 51) To produce. Next, in order to prevent the shape deformation of the vacuum heat insulating material 50 when observing the inside, the vacuum heat insulating material is filled in an epoxy resin, cut | disconnected, and then grind | polished, and the sample for porosity measurement is produced.

The produced sample was subjected to secondary electron image photographing using a scanning electron microscope (Hitachi Form S-4200), and image analysis was performed on the photographed secondary electron image, thereby forming the interior of the inclusion material 52. The area (space area) in which glass wool fibers do not exist in a certain area in Calcium is calculated as a percentage to set the porosity.

The porosity of the vacuum insulator of this embodiment is 90% or more. Thereby, heat conduction from the contact of fibers is suppressed, and heat insulation performance improves.

EMBODIMENT OF THE INVENTION Hereinafter, the Example by this invention is described in detail using drawing. In addition, an invention is not limited by this Example.

(Example 1)

The vacuum insulator 50 of Example 1 uses glass wool as the core material 51. Glass wool is produced by melting and spinning glass. Borosilicate glass was used for the glass forming glass wool. After melt | dissolving a glass in the melting furnace at the temperature of about 1300 degreeC, spinning was performed by the centrifugal method using the metal rotating body 100. As shown in FIG. The spun fibers were collected on a conveyor with a suction mechanism such that the basis weight was 1400 g / m 2. As is understood from the unit, the basis weight defines the weight when the collected fibers have a size of 1 m 2. In addition, in order to investigate the thickness of the spun fiber, the average fiber diameter was 3.5 micrometers when measured with the microneedle measuring device.

Moreover, when the length of the fiber collected directly under the rotating body 100 was measured, it became about 350 mm on average. Moreover, it was 25.7 when the compressive strength was measured.

The glass wool thus obtained was cut into a size of 500 mm in width x 1000 mm in length, and then dried in a 200 ° C drying furnace for 30 minutes, followed by laminating two sheets having a basis weight of 1400 g / m 2. Molecular sieves 13X) are interspersed between the layers of glass wool, and placed in a bag-shaped envelope made of three sides, vacuum-sucked the inside of the bag with a rotary pump for 10 minutes, and then 10 minutes with a diffusion pump. After the vacuum suction, the end of the bag was sealed with a heat seal.

About the obtained vacuum heat insulating material (thickness: about 12 mm), the heat insulating property was measured at 10 degreeC using AUTO-λ made from Eiko Seiki. The thermal insulation property was 116 (exponent). The heat insulation characteristic is represented by an index, and the higher it becomes, the better the heat insulation characteristic becomes.

From this result, it turned out that the vacuum heat insulating material excellent in heat insulation is obtained.

In addition, the vacuum insulation material 50 of various sizes was produced by the same method, and it applied to the refrigerator 1 of FIG. When the power consumption of this refrigerator 1 was measured, the result was about 3% lower than when it produced using the conventional vacuum heat insulating material. From this, it was found that the power consumption of the refrigerator 1 (apparatus requiring heat insulation of the low temperature part and the high temperature part) can be reduced by using the vacuum heat insulating material of the present embodiment.

(Example 2)

In the vacuum insulator of the second embodiment, glass wool is used as the core material as in the first embodiment. When the thickness of the spun fiber was measured with a microneedle measuring instrument, the average fiber diameter was 3.5 µm. Moreover, when the length of the fiber collected directly under the rotating body 100 was measured, it became about 180 mm as an average. Moreover, it was 23.4 when the compressive strength was measured.

The glass wool thus obtained was cut into a size of 500 mm in width x 1000 mm in length, and then dried in a 200 ° C drying furnace for 30 minutes, followed by laminating two sheets having a basis weight of 1400 g / m 2. With Molecular Sieves 13X), three bags were placed in a shell-like envelope and the inside of the bag was vacuum sucked for 10 minutes with a rotary pump, followed by vacuum suction for 10 minutes with a diffusion pump. Enclosed with a heat seal.

About the obtained vacuum heat insulating material (thickness: about 12 mm), the heat insulating property was measured at 10 degreeC using AUTO-λ made from Eiko Seiki. The thermal insulation property was 120 (exponent).

From this result, it turned out that the vacuum heat insulating material excellent in heat insulation is obtained.

In addition, a vacuum insulator having a size of 800 mm × 1200 mm and a thickness of 15 mm was produced in the same manner, and was applied as a heat insulating material of a storage tank of a heat pump water heater. A cross-sectional schematic diagram is shown in FIG. The hot water heated by the heat pump unit is stored in the water storage tank 60 of the heat pump water heater. When hot water is not used, when the hot water in the tank is lowered, it needs to be boiled again, and thus, the coefficient of performance (COP) of the hot water heater is lowered. An improvement of about 10% was confirmed as a result of comparing the COP of the case of applying the vacuum insulator 50 of the present example with the case of using the conventional vacuum insulator. From this, it was found that the power consumption of the heat pump hot water heater (apparatus requiring heat insulation of the high temperature portion) is kept low.

(Comparative Example 1)

In Comparative Example 1, glass wool is used as the core as in Examples 1 and 2. When the thickness of the spun fiber was measured with a microneedle measuring instrument, the average fiber diameter was 6.0 µm. Moreover, when the length of the fiber collected directly under the rotating body 100 was measured, it became about 250 mm as an average. Moreover, it was 21.7 when the compressive strength was measured.

The glass wool thus obtained was cut into a size of width 500 mm x length 1000 mm, dried in a drying furnace at 200 ° C. for 30 minutes, and then laminated on two sheets of a basis weight of 1400 g / m 2 and obtained by a getter agent (Union Showa, Mole). With three sheaths, 3 bags were put in a bag-like outer shell material, and the inside of the bag was vacuum sucked for 10 minutes with a rotary pump, and after vacuum suction for 10 minutes with a diffusion pump, the end of the bag was heated. Sealed with a seal.

About the obtained vacuum heat insulating material (thickness: about 12 mm), the heat insulating property was measured at 10 degreeC using AUTO-λ made from Eiko Seiki. The thermal insulation property was 100 (exponent).

From this result, it turned out that heat insulation property becomes low when fiber diameter is thick and compressive strength is low compared with Example 1, 2.

(Comparative Example 2)

In Comparative Example 2, as in Comparative Example 1, glass wool is used as the core material. When the thickness of the spun fiber was measured with a microneedle measuring instrument, the average fiber diameter was 4.2 탆. Moreover, when the length of the fiber collected directly under the rotating body 100 was measured, it became about 250 mm as an average. In addition, in this comparative example, glass wool was hot-pressed at 450 degreeC for 5 minutes. It was 6.3 when the compressive strength of this fiber aggregate was measured.

The glass wool thus obtained was cut into a size of width 500 mm x length 1000 mm, dried in a drying furnace at 200 ° C. for 30 minutes, and then laminated on two sheets of a basis weight of 1400 g / m 2 and obtained by a getter agent (Union Showa, Mole). With three sheaths, 3 bags were put in a bag-shaped envelope, and the inside of the bag was vacuum sucked for 10 minutes with a rotary pump, and after vacuum suction for 10 minutes with a diffusion pump, the end of the bag was heated. Sealed with a seal.

About the obtained vacuum heat insulating material (thickness: about 12 mm), the heat insulating property was measured at 10 degreeC using AUTO-λ made from Eiko Seiki. The thermal insulation property was 90 (exponent).

From this result, it turned out that heat insulation property becomes low when fiber diameter is thick and compressive strength is low compared with Example 1, 2.

(Comparative Example 3)

In Comparative Example 3, glass wool is used as the core as in Comparative Examples 1 and 2. When the thickness of the spun fiber was measured with a microneedle measuring instrument, the average fiber diameter was 4.5 µm. Moreover, when the length of the fiber collected directly under the rotating body 100 was measured, it became about 200 mm on average. Moreover, it was 18.7 when the compressive strength was measured.

The glass wool thus obtained was cut into a size of width 500 mm x length 1000 mm, dried in a drying furnace at 200 ° C. for 30 minutes, and then laminated on two sheets of a basis weight of 1400 g / m 2 and obtained by a getter agent (Union Showa, Mole). With three sheaths, 3 bags were put in a bag-shaped envelope, and the inside of the bag was vacuum sucked for 10 minutes with a rotary pump, and after vacuum suction for 10 minutes with a diffusion pump, the end of the bag was heated. Sealed with a seal.

About the obtained vacuum heat insulating material (thickness: about 12 mm), the heat insulation characteristic was measured at 10 degreeC using AUTO-λ made from Eiko Seiki. The thermal insulation property was 95 (exponent).

From this result, it turned out that heat insulation property becomes low when fiber diameter is thick and compressive strength is low compared with Example 1, 2.

In summary, from Fig. 7, the smaller the fiber diameter, the lower the thermal conductivity, and the heat insulating performance of the vacuum insulator tends to be improved.

In addition, if the compressive strength is small, a significant improvement in the thermal insulation performance cannot be expected. Therefore, the fiber length is increased to control the compressive strength to be 23 or more. Thereby, the vacuum heat insulating material excellent in heat insulation can be obtained.

Next, the generation of wrinkles in the outer cover material will be described. It is a figure explaining the generation | occurrence | production of the wrinkle of the outer shell material in a comparative example. It is a figure explaining the wrinkle generation suppression of the outer skin material in an Example. FIG. 9B is a diagram illustrating the time elapsed after the state of FIG. 9A. In addition, the core material 51 in each figure is shown typically, in order to make it easy to grasp the direction of a fiber.

In FIG. 8, the comparative example at the time of short fiber length is shown. When the fiber length of the core material 51 is short, the fiber assembly accommodated in the outer shell material 53 is nonuniform in the orientation of the fibers, and the fibers along the thickness direction are present in a substantial proportion relative to the fibers along the plane direction. In this case, when the inside of the shell material 53 is depressurized, the shell material 53 is drawn in to the core material 51 at a position where a relatively large number of fibers extending in the thickness direction are present. Then, wrinkles 53a are generated in the outer shell material 53 of the drawn portion. When the wrinkles 53a are generated in the vacuum insulator 50 of the comparative example, the core material 51 having a short fiber and weak repulsion force or elastic force does not have a force to push the wrinkles 53a against the pressure reducing force. Then, there is a method of repairing the wrinkle 53a of the shell material 53 that occurred once.

On the other hand, the fiber length of an Example is long as shown to FIG. 9A and FIG. 9B, and the orientation along a plane direction is easy to be obtained. In this configuration, if the pressure is reduced, the outer shell material 53 is drawn in to the core material 51 side as shown in Fig. 9A, and the wrinkles 53a are temporarily formed. However, the fiber aggregate constituting the core 51 has a long fiber length and orientation along the planar direction, and has a compressive strength of 23 or more. Therefore, it is provided with the force which pushes out the wrinkles 53a outward against a pressure reduction force. Therefore, since the force of restoring to the state of FIG. 9B is provided, formation of the wrinkles 53a of the outer shell material 53 can be suppressed. If the wrinkle 53a of the outer shell material 53 is generated, a crack will arise in the part, gas barrier property will fall, and long term vacuum degree maintenance will become difficult.

In each embodiment, since formation of the wrinkles 53a is suppressed, the gas barrier property of the outer cover material 53 can be maintained for a long time, and heat insulation performance can be maintained for a long time.

Moreover, the vacuum heat insulating material of each Example can also be applied to the various apparatuses, building members, especially a wall material etc. which need heat insulation.

(Example 3)

A third embodiment of the present invention will be described with reference to FIGS. 3, 4, and 10. It is a figure of the measurement result table of Examples 3-4 and Comparative Examples 4-5 of this invention.

In Example 3, as a fiber aggregate used as the core material of a vacuum heat insulating material, the fiber aggregate whose average fiber diameter of a fiber was 5.2 micrometers, and average fiber length was 250 mm.

In the measuring method of the fiber diameter, the fiber was spun to obtain a fiber aggregate, which was enlarged under a microscope to an average value of 30 measured values.

In addition, in the present Example, although the magnification measurement was performed by the microscope, there also exists a measuring method by a microneedle measuring machine. A microneedle measuring instrument is an instrument which measures fiber fineness, such as cotton, and measures fiber fineness by measuring the resistance with respect to the airflow of a certain amount of fiber masses. Specifically, the fiber of a certain weight is accommodated in a sample holder so that a fixed volume, and air of a fixed pressure is blown. Then, the fiber diameter is measured in µ order by reading the air flow rate at that time.

In the average fiber length, at the time of fiber spinning, the fibers were collected immediately after the fiber was formed, and the average fiber length was set from the average of the lengths of the focused fibers in a state where the fibers were not entangled. Moreover, in order to measure the fiber length of the glass wool which became once fiberized and became a fiber aggregate, since fibers are entangled, it loosens once or expands and measures one fiber. In addition, it is easy to measure the measurement immediately after spinning the fiber.

In addition, when the average fiber diameter is D and the average fiber length is L, a fiber having a large aspect value expressed in L / D has a large ratio of fiber length to fiber diameter and is easily entangled. Easy to arrange In other words, since the fiber is hardly oriented in the thickness direction, the thermal conductivity in the thickness direction can be lowered.

On the other hand, fibers having a small aspect value (L / D) have a small ratio of fiber length to fiber diameter, and short fibers tend to be arranged in the thickness direction, and are difficult to arrange in the planar direction. Therefore, the thermal conductivity in the thickness direction tends to be high.

The fiber aggregate of this Example 3 was produced using the fiber aggregate whose average fiber diameter D of a fiber is 5.2 micrometers, average fiber length L is 250 mm, and aspect value (L / D) is 48077.

After cutting glass wool to the size of width 500mm x length 1000mm, it dries for 30 minutes in the 200 degreeC drying furnace, and it laminates two sheets of basis weight 1400g / m <2>, and getters (Union Showa, Molecular Sieves 13X) ) Is interspersed between the fiber aggregate layers, placed in a bag-shaped envelope made of iron, and the inside of the bag is vacuum sucked for 10 minutes with a rotary pump, followed by vacuum suction for 10 minutes with a diffusion pump, and then the end of the bag. Sealed with a heat seal. In addition, a basis weight is a weight per 1 m <2> of a fiber aggregate, and a unit is represented by kg.

About the obtained vacuum heat insulating material (thickness: about 12 mm), the heat insulating property was measured at 10 degreeC using AUTO-λ made from Eiko Seiki. The thermal insulation property was 200 (exponent). The heat insulation characteristic is represented by an index, and the higher it becomes, the better the heat insulation characteristic becomes. From this result, it turned out that the vacuum heat insulating material excellent in heat insulation can be manufactured.

(Example 4)

The vacuum heat insulating material of Example 4 used the fiber aggregate whose average fiber diameter D of a fiber is 4.5 micrometers, average fiber length L is 250 mm, and an aspect value (L / D) is 55556.

Compared with Example 3, since the average fiber diameter D of the fibers is small and the average fiber length L is the same, the aspect value (L / D) becomes large.

After cutting glass wool to the size of width 500mm x length 1000mm, it dries for 30 minutes in the 200 degreeC drying furnace, and it laminates two sheets of basis weight 1400g / m <2>, and getters (Union Showa, Molecular Sieves 13X) ) Was put in a bag-shaped outer bag, and the inside of the bag was vacuum sucked for 10 minutes with a rotary pump, and after vacuum suction for 10 minutes with a diffusion pump, the end of the bag was sealed with a heat seal. .

About the obtained vacuum heat insulating material (thickness: about 12 mm), the heat insulating property was measured at 10 degreeC using AUTO-λ made from Eiko Seiki. The thermal insulation property was 218 (index). The heat insulation characteristic is represented by an index, and the higher it becomes, the better the heat insulation characteristic becomes. From this result, it turned out that the vacuum heat insulating material excellent in heat insulation can be manufactured.

(Comparative Example 4)

The vacuum heat insulating material of the comparative example 4 used the fiber aggregate whose average fiber diameter D is 6.0 micrometers, average fiber length L is 70 mm, and the aspect value (L / D) is 11667.

Compared with Examples 3 and 4, since the average fiber diameter D of the fiber is large and the average fiber length L is small, the aspect value (L / D) becomes small.

After cutting glass wool to the size of width 500mm x length 1000mm, it dries for 30 minutes in the 200 degreeC drying furnace, and it laminates two sheets of basis weight 1400g / m <2>, and getters (Union Showa, Molecular Sieves 13X) ) Was put in a bag-shaped outer bag, and the inside of the bag was vacuum sucked for 10 minutes with a rotary pump, and after vacuum suction for 10 minutes with a diffusion pump, the end of the bag was sealed with a heat seal. .

About the obtained vacuum heat insulating material (thickness: about 12 mm), the heat insulating property was measured at 10 degreeC using AUTO-λ made from Eiko Seiki. The thermal insulation property was 100 (exponent).

This is because compared with Examples 3 and 4, since the average fiber diameter D of the fiber is large, the heat conduction resistance is small, so that the thermal conductivity is increased and the average fiber length L is small, so that the fibers are easily arranged in the thickness direction, Since it is hard to arrange in a planar direction, it is because the thermal conductivity in the thickness direction became high.

Moreover, when a fiber is short, it deform | transforms so that the space | interval of fibers may fill up at the time of pressure reduction, and it is hard to form a space | gap. For this reason, the contact of fibers increases, and heat is easily transmitted through the contact.

From this result, it turned out that heat insulation characteristics become low when an aspect value (L / D) is small compared with Example 3, 4.

(Comparative Example 5)

The vacuum heat insulating material of the comparative example 5 used the fiber aggregate whose average fiber diameter D of fiber is 6.8 micrometers, average fiber length L is 180 mm, and aspect value (L / D) is 26471.

Compared with the comparative example 4, the average fiber diameter D and the average fiber length L of a fiber are made large, and an aspect value (L / D) becomes large.

After cutting glass wool to the size of width 500mm x length 1000mm, it dries for 30 minutes in the 200 degreeC drying furnace, and it laminates two sheets of basis weight 1400g / m <2>, and getters (Union Showa, Molecular Sieves 13X) ) Was put in a bag-shaped outer bag, and the inside of the bag was vacuum sucked for 10 minutes with a rotary pump, and after vacuum suction for 10 minutes with a diffusion pump, the end of the bag was sealed with a heat seal. .

About the obtained vacuum heat insulating material (thickness: about 12 mm), the heat insulating property was measured at 10 degreeC using AUTO-λ made from Eiko Seiki. The thermal insulation property was 126 (exponent).

This is because, as in Comparative Example 4, since the average fiber diameter is larger than those in Examples 3 and 4, the thermal conduction resistance is small and the thermal conductivity is high. In addition, because the average fiber length is short, the fibers are arranged in the thickness direction, and the thermal conductivity in the thickness direction is increased.

From this result, it turned out that heat insulation characteristics become low when an aspect value (L / D) is small compared with Example 3, 4.

In summary, from Fig. 10, by controlling the fiber length such that the average fiber diameter of the fiber is 4.5 µm or more and the aspect value (L / D) is 48000 or more, a vacuum insulator having excellent heat insulation can be obtained.

In addition, as the spinning time becomes longer, the pore diameter of the rotating body becomes larger due to friction and the like, and the fiber diameter to be spun increases gradually. In addition, the larger the fiber diameter, the smaller the thermal conduction resistance, and the higher the thermal conductivity. Accordingly, in the present embodiment, by controlling the fiber length so that the aspect value is 48000 or more, even if the fiber diameter increases by using the rotating body for a long time, by controlling the aspect value in relation to the fiber length, it is possible to suppress the decrease in the thermal insulation performance. have.

Moreover, by having an aspect value of 48000 or more and a porosity of 90% or more, heat conduction at the contact point of the entangled fiber is suppressed and it can be set as the vacuum heat insulating material excellent in heat insulation performance.

1 refrigerator
50, 50a, 50b, 50c vacuum insulation
51 heartwood
52 inclusions
53 Jacketed Material
53a wrinkle
100 rotator

Claims (7)

In the vacuum heat insulating material provided with the core material of a fiber assembly, and the outer skin material which has gas barrier property which covers the said core material,
The compressive strength (mm / (kg / m 2)), which is a value obtained by dividing the thickness (mm) by applying a predetermined load to the fiber assembly by the weight (kg / m 2) per m 2 of the fiber assembly, is 23 or more, characterized in that the vacuum insulator . The method of claim 1,
The core material having the compressive strength is a vacuum insulating material, characterized in that to push out the wrinkles formed by the shell material is drawn into the core material side by the reduced pressure in the shell material. 3. The method according to claim 1 or 2,
The porosity of the core material is a vacuum insulator, characterized in that more than 90%. In the vacuum insulation material which has a core material of a fiber laminated body, and the outer cover material which covers the said core material,
When the average D of the fiber diameter of the said fiber laminated body and the average L of fiber length, D is 4.5 micrometers or more, and the aspect value obtained by L / D is 48000 or more, The vacuum heat insulating material characterized by the above-mentioned. 5. The method of claim 4,
The porosity of the core material is a vacuum insulator, characterized in that more than 90%. A refrigerator in which a vacuum insulator and a foam insulator are disposed between an outer case and an inner case, wherein the vacuum insulator has a configuration according to claim 1 or 4. The apparatus which has a high temperature part WHEREIN: The apparatus provided with the said vacuum heat insulating material of Claim 1 or 4 which insulates the said high temperature part.

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