KR101560355B1 - Vacuum insulation material, refrigerator, equipment using vacuum insulation material - Google Patents

Abstract

SUMMARY OF THE INVENTION It is an object of the present invention to provide a vacuum insulator and a refrigerator having improved heat insulation performance.
In order to solve such a problem, the vacuum insulation material is a vacuum insulation material 50 having a core material 51 of a fiber aggregate and a cover material 53 having a gas barrier property covering the core material 51, (Mm / (kg / m 2)), which is a value obtained by dividing the thickness (mm) when the load is applied by the weight (kg / m 2) per 1 m 2 of the fibrous aggregate is 23 or more.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a vacuum insulator, a refrigerator, and a vacuum insulator using the vacuum insulator,

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

In recent years, the viewpoint of protecting the global environment and the improvement of the heat insulation of household appliances and industrial appliances have been examined from the viewpoint of energy saving. Resin foam or organic or inorganic fibers are used as a heat insulating material for inserting the device. However, when it is desired to improve the heat insulating property, it is necessary to increase the thickness of the heat insulating material. When the thickness of the heat insulating material is increased, the volume of the entire device is increased, and when the volume is not changed, the ratio of the space for mounting the parts or the like becomes lower. As a result, a vacuum heat insulator excellent in thermal insulation property such as resin foam or inorganic fiber has been proposed. The vacuum insulator is made by forming a shell material having gas barrier properties into a bag shape, putting a core material made of a fiber aggregate and a gettering agent for gas adsorption in the bag, decompressing the inside of the bag, do. The heat insulating property is 20 to 40 times higher than that of a conventional heat insulating material such as a resin foam or an inorganic fiber. Therefore, even if the thickness of the heat insulating material is made thin, it is possible to perform sufficient heat insulation.

In addition, various studies have been made to improve the heat insulating property and the functionality of the vacuum heat insulator.

BACKGROUND ART [0002] Japanese Patent Application Laid-Open No. 2006-38122 (Patent Document 1) and Japanese Patent Application Laid-Open No. 2011-236953 (Patent Document 2) are known as background arts in this technical field.

Patent Literature 1 discloses a laminate comprising a core material, a water adsorbent, a core material and an outer covering material having gas barrier properties covering the moisture adsorbent, wherein the core material is a glass fiber having an average fiber diameter of 3 to 5 m, And heated at 450 占 폚 for 5 minutes, which is lower than the melting point of the vacuum insulator.

Patent Document 2 discloses that "a core material having an average fiber diameter of not less than 3 μm and not more than 8 μm and an average fiber length of not less than 2 mm and not more than 10 mm in an inorganic or organic fiber laminate and a gas barrier property A vacuum insulator having a film, wherein the vacuum insulator has a porosity of 80% or more and 85% or less in the direction of extension in the direction of extension and a porosity of the cross section in the direction of thickness in the direction of heat insulation of 85% or more and less than 100% Quot; vacuum insulator ".

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

However, the vacuum insulator disclosed in Patent Document 1 uses a hot press method, and the fiber diameter of the glass wool is as small as 3 to 5 占 퐉, and the fibers are liable to dissolve.

Further, since the pressure by the press acts on the contact points between the fibers, the fibers are melted together.

Further, since the welded portion is a heat path for propagating heat in the heat insulating material, the thermal conductivity of the vacuum heat insulating material is lowered.

As described above, the fibers constituting the core material used in the conventional vacuum insulation material have a problem of propagation of heat caused by welding and propagation of heat caused by breaking of the fibers, that is, deterioration of the thermal conductivity of the vacuum insulation material.

The vacuum insulator disclosed in Patent Document 2 is a core material having an average fiber length of 2 mm or more and 10 mm or less and has a short fiber length. Therefore, it is difficult to control the orientation of the fibers, and the ratio of the fibers existing along the thickness direction from the plane of one side to the plane of the other side is increased. Then, by the fibers along the thickness direction, heat is easily transmitted from one plane to the other plane, and as a result, the thermal conductivity is increased.

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

In order to solve the above problems, for example, the configuration described in claims is adopted. The present invention includes a plurality of means for solving the above problems. For example, a vacuum insulator comprising a core material of a fiber aggregate and a shell material having gas barrier properties covering the core material, the vacuum insulator comprising: (Mm / (kg / m 2)), which is a value obtained by dividing the thickness (mm) of the fibrous aggregate by the weight per square meter (= basis weight) (kg /

In the vacuum insulator having the core material of the fiber laminate and the jacket material covering the core material, when D is an average length D of the fiber diameters of the fiber laminates and L is an average fiber length, / D has an aspect value of 48000 or more.

According to the present invention, it is possible to provide a vacuum insulator and a refrigerator with improved heat insulating performance.

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.
5 is a view for explaining a production method of a glass fiber.
6 is a front view showing a heat pump water heater according to the present embodiment.
7 is a diagram of measurement result tables of Examples 1 and 2 and Comparative Examples 1 and 2 of the present invention.
8 is a view for explaining the generation of wrinkles of the outer cover material in the comparative example;
FIG. 9A is a view for explaining the suppression of wrinkle generation of the outer cover material in the embodiment. FIG.
FIG. 9B is a diagram for explaining an elapsed time from the state of FIG. 9A; FIG.
Fig. 10 is a diagram of measurement result tables of Examples 1 and 2 and Comparative Examples 1 and 2 of the present invention. Fig.

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

(Configuration of Refrigerator 1)

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

The refrigerator 1 of the embodiment includes a refrigerator compartment 2 for cooling the refrigerator from the top to a refrigeration temperature, an ice-making compartment 3a for storing the ice cubes, an upper refrigerator compartment A freezing chamber 3b, a bottom freezing chamber 4, and a vegetable room 5 for storing vegetables.

The refrigerator compartment doors 6a and 6b, the ice-making compartment door 7a, the upper freezer compartment door 7b, the lower freezer compartment door 8 and the vegetable compartment door 9 are connected to the refrigerating compartment 2, The upper freezing chamber 3b, the lower freezing chamber 4, and the vegetables room 5 are opened and closed. In each of the doors, a foam insulating material 23 and a vacuum insulating material 50 are disposed.

The refrigerator compartment doors 6a and 6b shown in Figure 1 are rotatable about a hinge 10 and the like. The other freezing compartment door 7a, the upper freezing compartment door 7b, the lower freezing compartment door 8, The vegetable compartment door (9) is a pull-out door.

When the draw-out ice-making chamber door 7a, the upper freezing chamber door 7b, the lower freezing chamber door 8 and the vegetable chamber door 9 are taken out, the containers constituting each chamber are drawn out together with the doors.

2) is provided in each of the refrigerator compartment doors 6a and 6b, the freezing compartment door 7a, the upper freezer compartment door 7b, the lower freezing compartment door 8 and the compartment door 9 A packing (not shown) for sealing is attached to the outer peripheral edge of the refrigerator body 1H side.

A partition wall 12 for partitioning the refrigerating compartment 2 and the freezing compartment 3a and the upper freezing compartment 3b at the freezing temperature is disposed between the freezing compartment 2 and the freezing compartment 3a. The partition wall 12 is a heat insulating wall having a thickness of about 30 to 50 mm and is formed of a combination of a plurality of heat insulating materials such as styrofoam, foam insulating material (rigid urethane foam) and vacuum insulating material.

Since the ice making compartment 3a and the upper freezing compartment 3b and the lower freezing compartment 4 are equal to or smaller than the same freezing temperature and have a smaller temperature difference than the partitioning heat insulating wall for partitioning and insulating the partition, A member 13 is provided.

Between the lower freezing chamber (4) of the freezing temperature and the vegetable compartment (5) of the vegetable storage temperature, a partition wall (14) for partitioning and insulating the compartment is provided. The partition wall 14 is a heat insulating wall having a size of about 30 to 50 mm like the partition wall 12 and is made of styrofoam or foam insulation material (rigid urethane foam) or vacuum insulation material. In this manner, the partition walls of the storage compartment, which basically have different storage temperatures for the refrigeration temperature and the freezing temperature, are provided with the heat insulating walls 12, 14 having the heat insulating property.

The partition wall insulating walls 12 and 14 may be formed using expanded polystyrene 33 and vacuum insulator 50b as shown in Fig. 2, and are not particularly limited.

1, the interior of the refrigerator main body 1H is provided with a storage room for the refrigerating compartment 2, the ice making compartment 3a, the upper freezing compartment 3b, the lower freezing compartment 4 and the vegetable compartment 5 from above However, the arrangement of the respective storage chambers is not particularly limited to this. The opening and closing of the refrigerator compartment doors 6a and 6b, the ice making compartment door 7a, the upper freezing compartment door 7b, the lower freezing compartment door 8 and the vegetable compartment door 9 by rotation, And the like.

The refrigerator main body 1H shown in Fig. 2 is provided with a steel outer case 21 such as a PCM (Pre-Coated-Metal) steel plate and a resin inner case 22 such as ABS (Acrylonitrile Butadiene Styrene) have. The inner case 22 forms a refrigerating chamber 2, an ice making chamber 3a, an upper freezing chamber 3b, a lower freezing chamber 4, and a vegetables room 5.

The space formed between the outer case 21 and the inner case 22 is provided with a heat insulating portion as the heat insulating space 1s and insulates the respective storage spaces and the outer space in the refrigerator main body 1H.

A vacuum insulating material 50 is disposed in the heat insulating space 1s between the outer case 21 and the inner case 22 and a heat insulating material 1s such as a hard urethane foam is disposed in the heat insulating space 1s other than the vacuum heat insulating material 50. [ (23). The vacuum insulator 50 may be fixed to the outer case 21 or the inner case 22 by a fixing member or a supporting member not shown or may be fixed to the outer case 21 or the inner case 22 Is fixed.

In order to cool the respective chambers such as the refrigerating chamber 2, the ice making chamber 3a, the upper freezing chamber 3b, the lower freezing chamber 4 and the vegetables room 5 to a predetermined temperature, an ice making chamber 3a, a lower freezing chamber 4) is provided with a cooler 28 (see Fig. 2).

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

A blower 27 is disposed above the cooler 28 to circulate the cool air cooled by the cooler 28 inside the refrigerator 1 to maintain the cool air at a predetermined low temperature.

In the rear portion of the top surface 1H1 of the refrigerator main body 1H shown in Fig. 2, a recessed portion 40 for accommodating a power source board and the like on which the electric component 41 is mounted is formed. And controls various cooling operations of the refrigerator 1 and driving / stopping of various functions by control means such as a power supply board on which the electric component 41 is mounted. A cover 42 for covering the electric component 41 is provided above the concave portion 40. The height of the cover 42 is arranged to be substantially the same height as the top surface 1H1 of the refrigerator main body 1H in consideration of appearance design, . When the height of the cover 42 protrudes outward from the upper surface 1H1 of the refrigerator main body 1H, it is preferable that the height is within 10 mm.

The concave portion 40 is disposed in the concave portion 40 of the space for accommodating the electric component 41 in the concave portion on the side of the foaming heat insulating material 23 It is necessary to protrude to the inside of the refrigerator 1, and inevitably the contents of the refrigerator 1 will be sacrificed. On the other hand, when the inner volume of the refrigerator 1 is taken larger, the thickness of the foamed heat insulating material 23 between the concave portion 40 and the inner case 22 is reduced. Therefore, as shown in Fig. 2, a vacuum heat insulating material 50a is disposed in the foamed heat insulating material 23 opposed to the concave portion 40 to secure and enhance the heat insulating performance. In the present embodiment, the vacuum insulator 50a is a vacuum insulator 50a formed into a substantially Z-shape so as to extend over a case of an interior lamp not shown and an electric component 41. [

Since the compressor 30 and the condenser 31 disposed in the machine room in the lower portion of the rear surface of the refrigerator main body 1H shown in Fig. 2 (the lower right side of the refrigerator main body 1H in Fig. 2) The vacuum insulator 50c is disposed on the projection surface of the compressor 30 or the condenser 31 toward the inner case 22 in order to prevent the heat from entering the inner case 22 in the casing 22. 2, the vacuum insulator 50 is divided into a plurality of portions, but a single vacuum insulator 50c is bent to bend a plurality of portions to block the heat movement between the front of the machine room and the rear of the vegetable compartment 5 . In this case, the heat transfer through the sheath material (to be described in detail later) of the vacuum heat insulating material 50, that is, the so-called heat bridge phenomenon, is suppressed, and the heat insulating performance is improved.

(Basic structure of vacuum insulator 50)

Next, the construction of the vacuum insulator 50 (50a, 50b, 50c) will be described with reference to Figs. 3 and 4. Fig. 3 is a perspective view showing a vacuum insulator. 4 is a sectional view taken along the line C-C in Fig.

The vacuum insulator 50 includes a core 51 for forming a vacuum space, an encapsulating material 52 for maintaining the core 51 in a compressed state, an adsorbent 54 for adsorbing moisture, gas, And a cover material 53 having a gas barrier layer covering the core 51 held in a compressed state by the encapsulating material 52. As shown in Fig. In Fig. 4, the adsorbent 54 is emphatically shown.

The outer cover material 53 is disposed on both sides of the vacuum insulator 50 and has a bag shape in which portions of a certain width are adhered to each other by thermal welding from the outer edge of the laminate film of the same size. In addition, the fusion portion 50h prevents the heat bridge from being formed by bending toward the center.

The core member 51 of the vacuum heat insulating member 50 is a laminate of inorganic fibers which are not adhered or bonded with a binder or the like and glass wool of the following average fiber diameter is used.

As for the core material 51, it is advantageous in terms of heat insulation performance because outgas (generation of gas) is reduced by using a laminate of an inorganic fiber material. However, the core material 51 is not particularly limited to this. For example, Inorganic fibers such as wool, glass wool, glass fiber, alumina, silica alumina, silica, rock wool, and silicon carbide. Depending on the kind of the core material 51, the encapsulating material 52 may be unnecessary.

As the core material 51, an organic resin fiber material may be used in addition to the inorganic fiber material. In the case of the organic resin fiber, the use of the core material 51 such as the heat resistance temperature is not particularly restricted in its use. Specifically, polystyrene, polyethylene terephthalate, polypropylene or the like is formed into fibers with the fiber diameters of the following examples by a meltblown method, a spunbond method or the like, but it is not particularly limited as long as it is an organic resin or a fiberization method capable of forming fibers.

The fibrous aggregate is preferably made of inorganic fibers or organic fibers and has a low bulk density, and the compressive strength of the fibrous aggregate is measured as follows. The fibrous aggregate is cut into a predetermined size (100 mm x 100 mm), and a load is applied so as to be 25 g per 100 mm < 2 >. The value obtained by dividing the thickness (unit: mm) of the fibrous aggregate by weight and dividing the basis weight (weight per 1 m2 of fibrous aggregate, unit: kg / m2) by compressive strength (unit: mm / (kg / )). The higher the compressive strength is, the greater the resistance to weighting becomes, and it becomes a core material suitable for shape retention. In addition, as a method of bonding the fibers to each other, there are a use of a binder agent and a thermal press. When these methods are used, the compression strength is increased by bonding the fibers to each other. However, The thermal conductivity is deteriorated, which is undesirable.

The fiber diameter was measured by sprinkling the fibers into a fiber aggregate, which was enlarged by a microscope to obtain an average value of 30 measured values.

In the present embodiment, there is a method of performing enlargement measurement with a microscope or a measurement method using a micronaire measuring instrument. The micronaire measuring instrument measures the degree of fiber fineness of a face or the like and measures a fiber fineness by measuring a resistance of a predetermined amount of a fiber lump to an air flow. Specifically, fibers of a predetermined weight are accommodated in a sample holder so as to have a constant volume, and air at a constant pressure is blown. Then, by reading the air flow rate at that time, the fiber diameter is measured in the order of μ.

It is preferable that the fiber diameter is small, but it is preferably 10 占 퐉 or less and more preferably 5.2 占 퐉 or less in consideration of environmental consideration and industrial productivity.

The laminate structure of the outer cover material 53 is not particularly limited as long as it has gas barrier properties and is heat-weldable. In the present embodiment, the laminate structure of the surface (protective) layer, the first gas barrier layer, And a heat-sealable layer.

The surface layer is a resin film having a role as a protective material and the first gas barrier layer is provided with a metal vapor deposition layer on a resin film and the second gas barrier layer is provided with a metal vapor deposition layer on a resin film having high oxygen barrier property, 1 gas barrier layer and the second gas barrier layer are stacked so that the metal vapor deposition layers face each other. As for the thermal welding layer, a film having low hygroscopicity such as a surface layer was used.

Specifically, the outer covering member 53 is formed by laminating a surface layer of each film such as a biaxially stretched type polypropylene, polyamide, polyethylene terephthalate, or the like, a first gas barrier layer of biaxially oriented polyethylene terephthalate The second gas barrier layer is made of a biaxially oriented ethylene vinyl alcohol copolymer resin film with aluminum vapor deposition or a biaxially oriented polyvinyl alcohol resin film with aluminum vapor deposition or an aluminum foil, Of polyethylene, polypropylene and the like.

The layer structure and material of the four-layer laminate film are not particularly limited to these. For example, as the first and second gas barrier layers, a metal foil or a resin film may be provided with a resin-based gas barrier coating material such as an inorganic layered compound, polyacrylic acid, or the like, a gas barrier film made of DLC (diamond like carbon) For example, a polybutylene terephthalate film having a high oxygen barrier property may be used. Although the surface layer is the protection material for the first gas barrier layer, it is preferable to arrange a resin having low hygroscopicity, in order to improve the vacuum evacuation efficiency in the manufacturing process of the vacuum insulator 50. [

Further, since the resin film other than the metal foil used for the second gas barrier layer usually has a poor gas barrier property by moisture absorption, a resin with low hygroscopicity is arranged for the thermal welding layer, And to suppress the moisture absorption amount of the entire laminate film. Accordingly, in the vacuum exhaust process of the vacuum insulator 50 described above, since the moisture content of the encapsulant 53 can be reduced, the vacuum evacuation efficiency is greatly improved and the heat insulating performance is improved.

The lamination (adhesion) of each film is generally carried out by a dry lamination method through a two-component curing type urethane adhesive which is cured by two reaction heat sources. However, the kind of the adhesive and the bonding method are not particularly limited to this , A wet lamination method, a thermal lamination method, or the like.

In the present embodiment, a heat-sealable polyethylene film is used for the encapsulating material 52 and a physical adsorption type synthetic zeolite is used for the adsorbent 54. However, the present invention is not limited to these materials. The encapsulating material 52 may be a polypropylene film, a polyethylene terephthalate film, a polybutylene terephthalate film or the like, which is low in hygroscopicity and can be thermally fused, and has little outgassing.

The adsorbent 54 is adsorbed by water or gas, and both physical adsorption and chemical reaction adsorption can be used, and silica gel, calcium oxide, synthetic zeolite, activated carbon, potassium hydroxide, sodium hydroxide, lithium hydroxide and the like can be used.

(Production method of fiber aggregate (glass fiber)

A description will be given of the case of using glass wool as a core material 51 for use in the vacuum thermal insulator 50. Fig. The glass wool is not thermally cured by binder bonding or hot pressing but has flexibility after being packed with the encapsulating material 52 (high density polyethylene as an example) in a state of being flexible in a board shape and having flexibility, Degassing. The core material 51 pressed by the encapsulating material 52 is inserted into the bag-like shell material 53 and is opened and then the encapsulating material 52 and the envelope material 53 are vacuum-packed together, (50). The glass forming the glass wool uses borosilicate glass.

Here, FIG. 5 is a view for explaining a method for producing a glass fiber. The molten glass G is injected from the nozzle 101 connected to the glass melting furnace 100 toward the bottom of the hollow cylindrical cylindrical rotating body (spinner) 100. The hollow cylindrical cylindrical rotating body 100 rotates at a high speed around the rotating shaft 103 and the molten glass G thus charged is raised at the side wall of the rotating body 100 by the action of the centrifugal force. The molten glass G is ejected from pores 105 formed on the side wall of the rotating body 100. The molten glass G thus jetted is heated by a heating means 102 (flame radiating means such as a burner) which heats in the direction of arrow H. Here, the arrow H direction is a direction along the vertical direction of the plurality of pores 105 provided on the sidewall of the rotating body 100.

A gas discharging means 104 for discharging a gas is arranged concentrically around the side wall of the rotating body 100 at a discharge port of the heating means 102 (in the vicinity of the arrowhead of the arrow H) Respectively.

In this configuration, the molten glass G discharged from the plurality of pores 105 to the outside of the rotating body 100 is formed on filaments of a wire. The fibers are guided in the heating direction H of the heating means 102 to be made narrow in diameter and proceed downward. By the gas in the direction of the arrow F discharged from the gas discharging means 104, the length of the fibers, The density of the aggregate, and the like are adjusted.

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

As the fiber diameter becomes larger, individual heat conduction becomes easier and the thermal conduction resistance becomes smaller. When this fiber is used as a vacuum insulator, the heat insulating performance tends to deteriorate.

In order to prevent deterioration of the heat insulating performance, it is necessary to replace the pores 105 of the rotating body 100 with the new rotating body 100 at a time when the pores 105 reach a certain size. However, It is undesirable because the price is increased and the productivity is impaired.

Here, in the vacuum heat insulating material 50, the porosity, which is a ratio occupied by the space in the vacuum state other than the core 51 and the core 51 inside the encapsulating material 52 on the end surface of the vacuum insulating material 50, The measurement method of the above is shown below.

First, glass wool fibers prepared with predetermined fiber diameters and fiber lengths were produced and vacuum insulator 50 for measuring porosity (core material size 20 x 20 x 10t (mm)) using them as a core material (core material 51) . Next, in order to prevent the shape of the vacuum insulator 50 from being deformed when the inside is observed, a vacuum insulator is filled in the epoxy resin and then cut and polished to prepare a sample for measuring the porosity.

The produced sample was subjected to secondary electron photographing using a scanning electron microscope (Model S-4200 manufactured by Hitachi), image analysis was performed on the photographed secondary electron image, and the inside of the containing material 52 (Space area) in which the glass wool fibers do not exist in a certain area in the glass wool fibers is calculated as a percentage to obtain a porosity.

The porosity of the vacuum insulator of this embodiment is 90% or more. As a result, heat conduction from the contact points of the fibers is suppressed, and the heat insulating performance is improved.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the embodiments.

(Example 1)

The vacuum insulator 50 of the first embodiment uses glass wool as the core material 51. Glass wool is made by melt-spinning glass. The glass forming the glass wool was borosilicate glass. After the glass was melted at a temperature of about 1300 DEG C in the melting furnace, spinning was carried out by a centrifugal method using a rotating body 100 made of metal. The spun fibers were collected on a conveyor having a suction mechanism so as to have a basis weight of 1400 g / m 2. The basis weight is defined as the weight when the collected fibers have a size of 1 m < 2 > as seen from the unit. Further, in order to investigate the thickness of the spinning fiber, the average fiber diameter was measured by a micronaire measuring device to find that the average fiber diameter was 3.5 mu m.

In addition, the length of the fiber collected just under the rotating body 100 was measured and found to be about 350 mm on average. In addition, the compression strength was measured to be 25.7.

The glass wool thus obtained was cut into a size of 500 mm wide × 1000 mm long and dried in a drying furnace at 200 ° C. for 30 minutes and then two sheets each having a basis weight of 1400 g / Molecular Sieves 13X) were scattered between the layers of the glass wool, and the three chambers were placed in a jacket made of iron and formed into a bag shape. The inside of the bag was vacuum-sucked with a rotary pump for 10 minutes, After vacuum suction, the end of the bag was sealed with a heat seal.

The insulation property of the obtained vacuum insulation material (thickness: about 12 mm) was measured at 10 캜 using AUTO-λ manufactured by Eiko Seiki Co., The insulation property was 116 (exponent). The adiabatic characteristic is represented by an index, and the higher the adiabatic characteristic is, the better the adiabatic characteristic becomes.

From these results, it was found that a vacuum heat insulating material having excellent heat insulating properties was obtained.

In the same manner, a vacuum insulator 50 of various sizes was manufactured and applied to the refrigerator 1 shown in Fig. When the power consumption of the refrigerator 1 was measured, it was found to be about 3% lower than in the case of using a conventional vacuum insulator. Thus, it has been found that by using the vacuum insulation material of this embodiment, the power consumption of the refrigerator 1 (equipment requiring insulation at low temperature and high temperature) can be suppressed to a low level.

(Example 2)

As the vacuum insulator of Example 2, glass wool is used as a core material as in the first embodiment. The thickness of the spinning fibers was measured by a micronaire meter, and the average fiber diameter was 3.5 탆. In addition, the length of fibers taken under the rotating body 100 was measured and found to be about 180 mm on average. Further, the compressive strength was measured and found to be 23.4.

The glass wool thus obtained was cut into a size of 500 mm wide × 1000 mm long and dried in a drying furnace at 200 ° C. for 30 minutes and then two sheets each having a basis weight of 1400 g / The inner part of the bag was vacuum-sucked for 10 minutes by a rotary pump, and then the inside of the bag was vacuum-sucked with a diffusion pump for 10 minutes, Sealed with a heat seal.

The insulation property of the obtained vacuum insulation material (thickness: about 12 mm) was measured at 10 캜 using AUTO-λ manufactured by Eiko Seiki Co., The adiabatic property was 120 (exponent).

From these results, it was found that a vacuum heat insulating material having excellent heat insulating properties was obtained.

In the same manner, a vacuum insulator having a size of 800 mm × 1200 mm and a thickness of 15 mm was fabricated and applied as a heat insulating material for 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 storage tank 60 of the heat pump water heater. When the hot water in the tank is lowered when the hot water is not used, it is necessary to boil again, so that the coefficient of performance (COP) of the hot water heater is lowered. When comparing the case of applying the vacuum insulator 50 of the present embodiment and the COP of the conventional vacuum insulator, improvement of about 10% was confirmed. From this, it has been found that the power consumption of the heat pump water heater (equipment requiring heat insulation of the high temperature portion) is suppressed to be low.

(Comparative Example 1)

In Comparative Example 1, as in Examples 1 and 2, glass wool is used as a core material. The thickness of the spun fibers was measured with a micronaire meter, and the average fiber diameter was 6.0 mu m. In addition, the length of fibers taken under the rotating body 100 was measured and found to be about 250 mm on average. Also, the compressive strength was measured to be 21.7.

The glass wool thus obtained was cut into a size of 500 mm wide × 1000 mm long and dried in a drying furnace at 200 ° C. for 30 minutes. Two pieces of the glass wool having a basis weight of 1400 g / m 2 were laminated and a getter agent (Union Showa Co., The inside of the bag was vacuum-sucked for 10 minutes by a rotary pump, and then the bag was vacuum-sucked with a diffusion pump for 10 minutes. Then, the end of the bag was hit with a heat pump Sealed with a seal.

The insulation property of the obtained vacuum insulation material (thickness: about 12 mm) was measured at 10 캜 using AUTO-λ manufactured by Eiko Seiki Co., The insulation property was 100 (exponent).

From these results, it was found that the fiber diameter was thicker than that in Examples 1 and 2, and the heat insulating property was lowered when the compressive strength was low.

(Comparative Example 2)

In Comparative Example 2, glass wool is used as a core material as in Comparative Example 1. [ The thickness of the spun fibers was measured with a micronaire meter, and the average fiber diameter was 4.2 m. In addition, the length of fibers taken under the rotating body 100 was measured and found to be about 250 mm on average. In this comparative example, the glass wool was heat-pressed at 450 DEG C for 5 minutes. The compressive strength of this fibrous aggregate was measured to be 6.3.

The glass wool thus obtained was cut into a size of 500 mm wide × 1000 mm long and dried in a drying furnace at 200 ° C. for 30 minutes. Two pieces of the glass wool having a basis weight of 1400 g / m 2 were laminated and a getter agent (Union Showa Co., The inner part of the bag was vacuum-sucked for 10 minutes by a rotary pump, and after suctioning for 10 minutes by a diffusion pump, the end of the bag was hit with a heat pump Sealed with a seal.

The insulation property of the obtained vacuum insulation material (thickness: about 12 mm) was measured at 10 캜 using AUTO-λ manufactured by Eiko Seiki Co., The insulation property was 90 (exponent).

From these results, it was found that the fiber diameter was thicker than that in Examples 1 and 2, and the heat insulating property was lowered when the compressive strength was low.

(Comparative Example 3)

In Comparative Example 3, as in Comparative Examples 1 and 2, glass wool is used as a core material. The thickness of the spun fibers was measured with a micronaire meter, and the average fiber diameter was 4.5 탆. In addition, the length of the fibers collected under the rotating body 100 was measured and found to be about 200 mm on average. In addition, the compressive strength was measured to be 18.7.

The glass wool thus obtained was cut into a size of 500 mm wide × 1000 mm long and dried in a drying furnace at 200 ° C. for 30 minutes. Two pieces of the glass wool having a basis weight of 1400 g / m 2 were laminated and a getter agent (Union Showa Co., The inner part of the bag was vacuum-sucked for 10 minutes by a rotary pump, and after suctioning for 10 minutes by a diffusion pump, the end of the bag was hit with a heat pump Sealed with a seal.

The adiabatic characteristics of the obtained vacuum insulation material (thickness: about 12 mm) were measured at 10 캜 using AUTO-λ manufactured by Eiko Seiki Co., Ltd. The insulation property was 95 (exponent).

From these results, it was found that the fiber diameter was thicker than that in Examples 1 and 2, and the heat insulating property was lowered when the compressive strength was low.

From the above results, it can be seen from Fig. 7 that as the fiber diameter becomes smaller, the thermal conductivity also becomes lower and the heat insulating performance of the vacuum heat insulator tends to be improved.

If the compressive strength is small, it is impossible to expect a significant improvement in the heat insulating performance. Therefore, the compressive strength is controlled to be 23 or more by increasing the fiber length. As a result, a vacuum heat insulating material excellent in heat insulating property can be obtained.

Next, suppression of wrinkle generation of the outer cover material will be described. Fig. 8 is a view for explaining the occurrence of wrinkles of the outer cover material in the comparative example. Fig. Fig. 9A is a view for explaining suppression of wrinkle generation of the outer cover material in the embodiment. Fig. FIG. 9B is a diagram for explaining a time lapse after the state of FIG. 9A. FIG. The core member 51 in each drawing is schematically shown to facilitate understanding of the orientation of the fibers.

8 shows a comparative example in which the fiber length is short. When the fiber length of the core material 51 is short, the fiber aggregate housed in the jacket material 53 is uneven in the orientation of the fibers, and the fibers along the thickness direction exist in a considerable ratio with respect to the fibers along the planar direction. In this case, when the inside of the outer shell 53 is depressurized, the outer shell 53 is drawn into the core 51 at a position where there are a relatively large number of fibers extending in the thickness direction. Then, a corrugation 53a is generated in the outer covering material 53 of the drawn portion. When the corrugations 53a are generated in the vacuum insulator 50 of the comparative example, the cores 51 having a short fiber and weak repulsive force or elasticity do not have a force for restoring the corrugation 53a against the reduced pressure. There is no way to repair the fold 53a of the jacket material 53 that has occurred once.

On the other hand, the fiber length of the embodiment is long as shown in Figs. 9A and 9B, and orientation along the plane direction is easily obtained. In this configuration, when the pressure is reduced, as shown in FIG. 9A, the cover material 53 is drawn in a part of the core 51 side to form the corrugation 53a temporarily. However, the fibrous aggregate constituting the core material 51 has a long fiber length, an orientation along the planar direction, and a compressive strength of 23 or more. Therefore, it has the force to push the corrugated sheet 53a outward against the depressurizing force. Therefore, since the force for restoring the state shown in Fig. 9B is provided, the formation of the corrugations 53a of the casing member 53 can be suppressed. When the corrugations 53a of the casing member 53 are generated, a crack is generated in the corrugations 53a, and the gas barrier property is deteriorated, making it difficult to maintain the vacuum degree for a long term.

In each embodiment, since the formation of the corrugations 53a is suppressed, the gas barrier property of the casing member 53 can be maintained for a long time, and the heat insulating performance can be maintained for a long period of time.

In addition, the vacuum insulator of each embodiment can be applied to a variety of appliances, architectural members, especially wall materials and the like that require heat insulation.

(Example 3)

A third embodiment of the present invention will be described with reference to Figs. 3, 4, and 10. Fig. Fig. 10 is a diagram showing measurement result tables of Examples 3 to 4 and Comparative Examples 4 to 5 of the present invention. Fig.

In Example 3, a fiber aggregate having an average fiber diameter of 5.2 占 퐉 and an average fiber length of 250 mm was used as the fiber aggregate serving as the core material of the vacuum insulator.

The fiber diameter was measured by sprinkling the fibers into a fiber aggregate, which was enlarged by a microscope to obtain an average value of 30 measured values.

In the present embodiment, magnification measurement is performed by a microscope, but there is also a measurement method by a micronaire measuring device. The micronaire meter measures the fiber fineness of a cotton or the like and measures the fiber fineness by measuring the resistance of a certain amount of the fiber loom against the air flow. Specifically, fibers of a predetermined weight are accommodated in a sample holder so as to have a constant volume, and air at a constant pressure is blown. Then, by reading the air flow rate at that time, the fiber diameter is measured in the order of μ.

As to the average fiber length, the fibers were gathered immediately after the fiber was spun at the time of fiber spinning, and the average fiber length was determined from the average of the lengths of fibers gathered in a state in which the fibers were not entangled. Further, in order to measure the fiber length of the glass wool which is made into a fibrous aggregate once, since the fibers are entangled with each other, the fibers are loosened once or one fiber is enlarged and measured. In addition, measurement is easy as it is measured immediately after the fiber is radiated.

When the average fiber diameter is D and the average fiber length is L, the fiber having a large aspect ratio indicated by L / D is liable to have a large fiber length to fiber diameter and entangled. Therefore, It is easy to arrange. In other words, since the fibers are hard to be oriented in the thickness direction, the thermal conductivity in the thickness direction can be lowered.

On the other hand, a fiber having a small aspect ratio (L / D) has a small fiber length ratio to a fiber diameter, and a short fiber is easily arranged in a thickness direction, and is difficult to be arranged in a planar direction. Therefore, the thermal conductivity in the thickness direction tends to be high.

The fiber aggregate of Example 3 was produced by using a fiber aggregate having an average fiber diameter D of 5.2 mu m, an average fiber length L of 250 mm, and an aspect ratio (L / D) of 48077.

The glass wool was cut into a size of 500 mm wide × 1000 mm long and dried in a drying furnace at 200 ° C. for 30 minutes and then two sheets each having a basis weight of 1400 g / m 2 were laminated and a getter agent (Molecular Sieves 13X ) Were sandwiched between the fibrous aggregate layers, and the three chambers were placed in a jacket made of a steel bar, and the inside of the bag was vacuum-sucked for 10 minutes by a rotary pump. After vacuum suction for 10 minutes by a diffusion pump, Was sealed with a heat seal. The basis weight means the weight per 1 m 2 of the fibrous aggregate, and the unit is expressed in kg.

The insulation property of the obtained vacuum insulation material (thickness: about 12 mm) was measured at 10 캜 using AUTO-λ manufactured by Eiko Seiki Co., The insulation property was 200 (exponent). The adiabatic characteristic is represented by an index, and the higher the adiabatic characteristic is, the better the adiabatic characteristic becomes. From these results, it has been found that a vacuum insulation material having excellent heat insulating properties can be produced.

(Example 4)

The vacuum insulation material of Example 4 used a fiber aggregate having an average fiber diameter D of 4.5 占 퐉, an average fiber length L of 250 mm, and an aspect ratio (L / D) of 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 ratio (L / D) becomes large.

The glass wool was cut into a size of 500 mm wide × 1000 mm long and dried in a drying furnace at 200 ° C. for 30 minutes and then two sheets each having a basis weight of 1400 g / m 2 were laminated and a getter agent (Molecular Sieves 13X ). The three bags were placed in a bag-shaped outer bag made of iron and the inside of the bag was vacuum-sucked with a rotary pump for 10 minutes. Then, the bag was vacuum-sucked with a diffusion pump for 10 minutes and then the end of the bag was sealed with a heat seal .

The insulation property of the obtained vacuum insulation material (thickness: about 12 mm) was measured at 10 캜 using AUTO-λ manufactured by Eiko Seiki Co., The insulation property was 218 (exponent). The adiabatic characteristic is represented by an index, and the higher the adiabatic characteristic is, the better the adiabatic characteristic becomes. From these results, it has been found that a vacuum insulation material having excellent heat insulating properties can be produced.

(Comparative Example 4)

The vacuum insulation material of Comparative Example 4 used a fiber aggregate having an average fiber diameter D of 6.0 mu m, an average fiber length L of 70 mm, and an aspect ratio (L / D) of 11667.

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

The glass wool was cut into a size of 500 mm wide × 1000 mm long and dried in a drying furnace at 200 ° C. for 30 minutes and then two sheets each having a basis weight of 1400 g / m 2 were laminated and a getter agent (Molecular Sieves 13X ). The three bags were placed in a bag-shaped outer bag made of iron and the inside of the bag was vacuum-sucked with a rotary pump for 10 minutes. Then, the bag was vacuum-sucked with a diffusion pump for 10 minutes and then the end of the bag was sealed with a heat seal .

The insulation property of the obtained vacuum insulation material (thickness: about 12 mm) was measured at 10 캜 using AUTO-λ manufactured by Eiko Seiki Co., The insulation property was 100 (exponent).

This is because compared with Examples 3 and 4, since the average fiber diameter D of the fibers is large, the thermal conduction resistance is reduced and the thermal conductivity is increased, and the average fiber length L is small, It is difficult to be arranged in the plane direction, so that the thermal conductivity in the thickness direction is increased.

When the fibers are short, they are deformed to fill the gaps between the fibers at the time of decompression, and voids are hard to form. As a result, the number of contact points between the fibers increases, and heat is likely to be transmitted through the contact points.

From these results, it was found that when the aspect ratio (L / D) was small as compared with Examples 3 and 4, the heat insulating property was lowered.

(Comparative Example 5)

The vacuum insulation material of Comparative Example 5 used a fiber aggregate having an average fiber diameter D of 6.8 mu m, an average fiber length L of 180 mm, and an aspect ratio (L / D) of 26471. [

Compared with Comparative Example 4, the average fiber diameter D and the average fiber length L of the fibers are increased, and the aspect ratio (L / D) becomes larger.

The glass wool was cut into a size of 500 mm wide × 1000 mm long and dried in a drying furnace at 200 ° C. for 30 minutes and then two sheets each having a basis weight of 1400 g / m 2 were laminated and a getter agent (Molecular Sieves 13X ). The three bags were placed in a bag-shaped outer bag made of iron and the inside of the bag was vacuum-sucked with a rotary pump for 10 minutes. Then, the bag was vacuum-sucked with a diffusion pump for 10 minutes and then the end of the bag was sealed with a heat seal .

The insulation property of the obtained vacuum insulation material (thickness: about 12 mm) was measured at 10 캜 using AUTO-λ manufactured by Eiko Seiki Co., The insulation property was 126 (exponent).

This is because, as in Comparative Example 4, since the average fiber diameter is larger than that in Examples 3 and 4, the thermal conduction resistance is small and the thermal conductivity is high. Further, since 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 these results, it was found that when the aspect ratio (L / D) was small as compared with Examples 3 and 4, the heat insulating property was lowered.

From the above, it can be seen from Fig. 10 that the fiber length is controlled so that the average fiber diameter of the fibers is 4.5 mu m or more and the aspect ratio (L / D) is 48000 or more.

Further, if the spinning time is prolonged, the pore diameter of the rotating body becomes large due to friction or the like, and the fiber diameter to be radiated tends to gradually increase. Further, when the fiber diameter becomes larger, the thermal conduction resistance becomes smaller and the thermal conductivity becomes higher. Thus, in this embodiment, by controlling the fiber length and setting the aspect value to 48000 or more, deterioration of the heat insulating performance can be suppressed by controlling the aspect value in relation to the fiber length even if the fiber diameter is increased by using the rotating body for a long time have.

By setting the void ratio to 90% or more with an aspect value of 48000 or more, thermal conduction at the contact points of the entangled fibers is suppressed, and a vacuum insulating material excellent in heat insulating performance can be obtained.

1 Refrigerator
50, 50a, 50b, 50c vacuum insulator
51 Core
52 Nesting material
53 Sheath material
53a wrinkles
100 times overall

Claims (7)

A vacuum insulator comprising a core material of a fiber aggregate and a shell material having a gas barrier property covering the core material,
(Mm / (kg / m 2)) which is a value obtained by dividing the thickness (mm) of the fibrous aggregate when a predetermined load is applied divided by the weight per square meter of the fibrous aggregate (kg / m 2)
D is the average fiber diameter of the fibrous aggregate, D is the average length of the fibers, and D is the average fiber length, and the aspect ratio obtained by L / D is 48000 or more. delete The method according to claim 1,
Wherein the core material has a porosity of 90% or more. delete delete Wherein a vacuum insulation material and a foam insulation material are disposed between the outer case and the inner case, wherein the vacuum insulation material has the configuration according to claim 1. An apparatus having a high temperature part, characterized by comprising the vacuum heat insulator according to claim 1 for inspecting the high temperature part.

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