KR20070035607A - Vacuum heat insulation material - Google Patents

Abstract

The present invention provides a vacuum insulator having a very low environmental load during production and recycling, and excellent in handleability and workability, and maintaining a good thermal insulation property over a long period of time. The present invention comprises at least a core material and an outer cover material capable of accommodating the core material and maintaining the inside at a reduced pressure, wherein the core material contains 50% by weight or more of polyester fibers having a fiber thickness of 1 to 6 denier. It is related with the vacuum heat insulating material characterized by being a phase fiber assembly.

Description

Vacuum Insulation Material {VACUUM HEAT INSULATION MATERIAL}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to vacuum insulators used as insulation materials for refrigerators, vending machines, cold storage boxes, cold storage cars, storage tanks, storage tanks, vacuum insulated pipes, molded ceilings of automobiles, bathtubs, and the like.

Background Art Conventionally, insulation materials having various structures and performances have been used for insulation of refrigerators, vending machines, cold storage boxes, cold storage cars, storage tanks, storage tanks, vacuum insulation piping, molded ceilings of automobiles, bathtubs, and the like. In recent years, many vacuum insulators having very good thermal insulation have been used for the above applications. The vacuum insulator generally has a structure in which a core member is filled in an external packing member made of a gas-barrier metal vapor deposition film or the like, and the inside is sealed under reduced pressure. Although the heat insulating property, productivity, and handling performance of such a vacuum heat insulating material largely depend on the said core material, as a core material currently universally used, a continuous foamed polyurethane foam (patent document 1), glass fiber aggregates (patent documents 2 and 3), and glass fiber aggregates are mentioned. The composite (patent document 4) of another thermoplastic resin fiber is mentioned.

However, the general purpose vacuum insulation core material has the following problems. Although the core material using continuous foam polyurethane foam is very excellent in workability, handleability, light weight, etc., there exists a surface which is inferior in heat insulation compared with fibrous materials, such as glass fiber.

The core material using the glass fiber aggregate has a very excellent heat insulating property without generation of outgas (gas powder volatilized from the core material), but has a great disadvantage in handling and workability of the material itself called glass fiber. In order to improve the handleability, efforts have been made to improve the operation of inserting the core material into the outer cover material by needle punching the sheet of glass fiber, but the handleability and workability due to the material itself are improved. The difficulty could not be solved. In particular, at the time of recycling the core material, problems of work environment and handling still remain. For example, when the outer packaging material is opened during recycling, the glass fiber aggregate core material is scattered, which causes not only problems in handling and workability but also in terms of environmental load.

The core material using the composite of glass fiber aggregates and other thermoplastic resin fibers slightly improves handleability but is not satisfactory. In particular, Patent Document 4 describes a core material having a composition of 80% by mass of glass wool and 20% by mass of polypropylene resin fiber, and molded into a mat by a hot press method. However, there is still a problem of deterioration in workability due to the glass wool itself, and a problem of deterioration in heat insulation resulting from outgases generated from polypropylene resin fibers. In addition, from the point of mixing and using an organic fiber and an inorganic fiber, classification after use is very difficult, and recycling property is very low. Some combinations of fibers such as rock wool and pulp, such as thermoplastic fibers, have been reported, but since glass fibers are used, the handling and workability and environmental loads inherent in the glass fibers themselves are difficult. Still remains.

Vacuum insulating materials using only organic fibers such as thermoplastic resin fibers as core materials are also considered, but there are no commercially specified examples due to the problem of outgases generated from organic fibers. Although the example which used the 0.75d polyester fiber floc as a core material is also seen (patent document 5), when used as a fiber floc, handling is very bad and it is not considered a realistic product. Therefore, although it is also considered to make the spherical body into a sheet for the purpose of improving handleability, when using the ultrafine fibers as described above, the needle punching method is difficult to use, and therefore, the binder is formed by a chemical bonding method. When using out, there is a problem that outgas is generated, the change over time is large, and the thermal insulation is greatly reduced with time.

On the other hand, the use of vacuum insulators is gradually expanding in recent years. For example, the vacuum insulation material is wound on the cylindrical tank of a water supply equipment or the cylindrical piping of a piping installation from the outer periphery, and is coat | covered, and the use which improves the thermal efficiency of a tank or piping is mentioned. In such a use, the vacuum insulator needs to be deformed and brought into close contact with the outer circumferential surface of the tank or pipe, and furthermore, a through-hole part and a cutout part for allowing wiring or pipes to pass therethrough. It is required to install a notched area or a bent groove for bending. However, it was difficult to deform the conventional thick vacuum heat insulating material whose core material thickness after vacuum suction is 10 mm or more after vacuum suction. For example, even if the core material could be easily deformed before vacuum suction, it was difficult to manufacture a vacuum insulator using the modified core material.

Therefore, it is considered that the core material thickness after vacuum suction is set to 5 mm or less, for example, to facilitate deformation after vacuum suction. However, in the case where a core made of glass fiber having an average fiber length of 1 mm or less was used, sufficient curvature was not obtained when the thickness was thinned. That is, even if the obtained vacuum heat insulating material can be easily deformed, since it is going to return to flat form and a relatively large bending wrinkle arises in a deformation | transformation state, it is difficult to wind up or after winding up the said vacuum heat insulating material. The adhesion could not be achieved sufficiently.

As a technique for forming a through hole and a cutout portion in a vacuum insulator, a flat heat insulating core material having through holes and / or cutouts is stored in a bag from an opening of a bag made of a gas barrier packaging material, and then from the opening of the bag. A seal portion in which gas barrier packaging materials are fused together along a vacuum insulator side inner peripheral portion of the through hole and / or the cutout portion while evacuating the inside of the bag and maintaining the desired vacuum degree, and the opening of the bag. The method of forming the seal part which fused the gas barrier packaging materials of this by the press welding by a heating member is reported (patent document 6).

However, when evacuating the outer shell material (covering material) of the inner circumferential portion of the through hole or the cutout part or sealing the outer material, it depends on the film flexibility of the outer material or the film type of the outer material. In a hard core material such as inorganic powder, a heavy load is applied to the shell material at the inner circumferential portion, and a breakage of the shell material and a large void portion occur between the shell material and the core material. The same problem occurs when a plurality of core materials are accommodated in the outer cover material and the back surface of the outer cover material is sealed along the outer edge of the outer cover material and the outer circumferential portion of each core material. In particular, a problem is likely to occur in the portion between the plurality of core materials during the vacuum evacuation step.

However, it is also possible to smooth the core surface to improve the adhesion between the shell material and the core material. However, chamfering processing is required for the core material and the productivity is lowered. In particular, in the case of an inorganic core material, chamfering processing itself is cumbersome.

In addition, since either of the above vacuum insulators is manufactured by sealing the core member directly in the outer cover material and keeping the inside of the outer cover material under reduced pressure, the production efficiency of the vacuum insulator has been a problem. In other words, if the core material is directly accommodated in the outer cover material, scratches easily occur in the outer cover material, so that the yield of the vacuum insulator decreases. In addition, if the core material is directly accommodated in the outer cover material, the core material easily adheres to the finally sealed outer material opening part by static electricity or the like, and it is difficult to remove the attached core material sufficiently. Was formed between the inside and the outside of the outer cover material, and the yield of the vacuum insulator fell. The problem of such a yield fall was remarkable when using the cotton core material which is difficult to handle. Moreover, when accommodating a cotton core material directly in an outer cover material, since an accommodation operation | work is limited in view of the flaw of an outer cover material as mentioned above, it was difficult to accommodate so that it might become a uniform thickness. Therefore, heat insulation fell. Patent Document 1: Japanese Patent Application Laid-Open No. 1993-213561

Patent Document 2: Japanese Patent Application Laid-Open No. 1996-28776

Patent Document 3: Japanese Patent Laid-Open No. 1997-4785

Patent Document 4: Japanese Patent Application Laid-Open No. 2003-155651

Patent Document 5: Japanese Patent Application Laid-Open No. 2002-188791

Patent Document 6: Japanese Patent Application Laid-Open No. 1996-303686

Disclosure of the Invention

Problems to be Solved by the Invention

This invention consists of 1st invention, 2nd invention, and 3rd invention, These inventions are the vacuum heat insulating material with very low environmental load at the time of manufacture and recycling in common, and it is excellent in handleability and workability, and It is an object of the present invention to provide a vacuum insulator that maintains good thermal insulation over a long period of time.

In particular, the second invention aims to provide a vacuum insulator having a through hole and / or a cutout portion or a vacuum insulator having a plurality of core materials, which has good adhesion between the outer material and the core material and provides a vacuum insulator with little damage to the outer material. do.

Moreover, especially a 3rd invention aims at providing the vacuum heat insulating material excellent in the production efficiency.

Means to solve the problem

The first invention comprises at least a core material and an outer cover material for accommodating the core material and maintaining the inside at a reduced pressure, wherein the core material contains 50% by weight or more of polyester fibers having a fiber thickness of 1 to 6 denier. It relates to a vacuum insulator, characterized in that the sheet-like fiber aggregate (aggregate).

2nd invention is related with the vacuum heat insulating material in 1st invention which has the sealing part which the outer surface of the outer surface material fuse | welded in the peripheral part of the outer material, and the inner region of the said peripheral part.

In 1st invention, 3rd invention is related with the vacuum heat insulating material characterized by accommodating the inner material which accommodated the core material in the outer material in a reduced pressure state.

Although the organic fiber core material was not considered as a core material for vacuum heat insulating materials due to problems such as a decrease in heat insulating property due to outgas generation, the inventors of the present invention focus on polyester fibers having a specific thickness and form the fiber in a sheet form. What was settled was that it exhibited over time the heat insulation exceeding the conventional continuous bubble urethane foam, and came to complete this invention.

Effects of the Invention

Since the core material is comprised from the polyester fiber, the vacuum heat insulating material of 1st invention-3rd invention has small environmental load, and is very excellent in the recycling property after use. In addition, the vacuum insulators of the first to third inventions exhibit heat insulation that exceeds the vacuum insulator using the continuous foam urethane foam employed in refrigerators and the like for a long time, and is superior in handleability and workability as compared with glass fibers. Do.

In particular, in the first invention, the thin core material having a thickness after vacuum suction within a certain range shows a significantly improved curved formability. That is, since the polyester fibers constituting the core material, particularly the polyethylene terephthalate fibers, are flexible, the fibers behave smoothly in response to deformation inside the vacuum insulator even after vacuum suction. The vacuum insulator has a relatively weak restoring force at deformation, and furthermore has a relatively small and small bending wrinkle. Therefore, the said vacuum heat insulating material is easy to wind up to the cylindrical tank of a water supply equipment, the cylindrical piping of a piping installation, etc., Furthermore, sufficient close contact with them can be achieved. Moreover, it exhibits heat insulating property exceeding the vacuum heat insulating material using a continuous bubble foam, and is very excellent in handleability compared with glass fiber.

Moreover, especially in 1st invention, when using the core material which consists of at least 2 types of polyester fiber from which melting | fusing point differs, since it can process into a sheet form at comparatively low temperature by a thermal bonding method, while suppressing generation | occurrence | production of outgas, The handleability and workability of the core material can be improved. In particular, the handleability and workability are remarkably improved in comparison with the conventional fibrous core, and inferior to the urethane foam plate core.

Since the vacuum heat insulating material of 2nd invention has a through-hole part and / or a cutout part, or has a some core material, it can be used for various uses. In addition, since the flexibility of the fiber is abundant using a polyester fiber core material, vacuum exhaust is carried out at the inner peripheral part of the through hole and / or the cutout part, and at the outer peripheral part of each core material when storing the plurality of core materials in the outer cover material. The breakage of the cover material at the time of a process hardly occurs, and the adhesiveness of a cover material and a core material is good.

In the vacuum insulator of the third aspect of the invention, since the core is accommodated in the envelope in a state accommodated in the envelope, scratches are less likely to occur in the envelope, and moreover, attachment of the core to the envelope opening is unlikely to occur. Therefore, the yield of a vacuum heat insulating material improves and a production efficiency rises.

1 (A) to (H) are schematic diagrams showing examples of the structures of the low melting polyester fibers and the high melting polyester fibers.

FIG. 2 (A) is a schematic illustration of an example of the vacuum insulator of the second invention, and FIG. 2 (B) is a schematic cross-sectional view taken along the line I-I of the vacuum insulator in FIG.

3 (A) and 3 (B) are schematic flowcharts showing a part of the manufacturing method when the vacuum insulator of FIG. 2 is manufactured.

4 (A) is a schematic illustration of an example of the vacuum insulator of the second invention, and FIG. 4 (B) is a schematic cross-sectional view taken along the line II-II of the vacuum insulator in FIG. 4 (A).

5 (A) and 5 (B) are schematic flowcharts showing part of the manufacturing method when the vacuum insulator of FIG. 4 is manufactured.

FIG. 6 (A) is a schematic illustration of an example of the vacuum insulator of the second invention, and FIG. 6 (B) is a schematic cross-sectional view taken along the line III-III of the vacuum insulator in FIG. 6 (A).

7 (A) and 7 (B) are schematic flowcharts showing a part of the manufacturing method when the vacuum insulator of FIG. 6 is manufactured.

Explanation of the sign

1: heartwood 2: outer material

3A, 3B, 3C, 3D and 3E: Seal 3F: Through hole of vacuum insulation

3G: Seal part formed in process (c) 5: Through hole of core material

6: Adsorption part between outer back surface materials 11: Heartwood

12: outer material 13A, 13B, 13C, 13D and 13E: seal part

13F: part of cutout 13G: seal formed in step (c)

15: Through-hole of core material 16: Adsorption part between outer surface of outer cover materials

21: Heartwood 22: Sheathing

23A, 23B, 23C, 23D, and 23E: Seal

26: The adsorption part between the back surfaces of the outer covering material.

Best Mode for Carrying Out the Invention

(1st invention)

The vacuum insulator of the first invention consists of at least a core material and an outer cover material which accommodates the core material and can keep the inside at a reduced pressure.

In the first invention, the core material of the first embodiment is a sheet-like fiber aggregate containing polyester fibers having a fiber thickness of 1 to 6 denier, preferably 1 to 3 denier. In detail, the core material is obtained by processing the fiber aggregate containing the polyester fiber in the form of a sheet. By using such core material, handling and workability can be improved, and the environment at the time of manufacture and recycling The load can be reduced. Moreover, good heat insulation can be exhibited over a long period of time. The average fiber diameter of the polyester fiber having the fiber thickness is usually 9 to 25 µm, preferably 9 to 17 µm. The average fiber diameter was measured by processing two diameters per fiber with a CCD camera image with respect to 10 fibers, and obtained an average value of 20 diameters in total and used the average fiber diameter value.

"Sheet-like" means having a flat plate shape. If the core material is not in sheet form, such as when the fiber aggregate is used as it is, the handleability of the core material is deteriorated, so that the process of storing the core material in the outer cover material is complicated, and workability is deteriorated. Moreover, initial heat insulation is not expressed.

The thickness of the sheet-like fiber assembly (core material) of the first embodiment is not particularly limited as long as the object of the first invention is achieved, and is usually about 0.1 mm to 100 mm when preferably a vacuum insulator (after vacuum suction), preferably May be about 1 mm to 50 mm, particularly about 5 mm to 20 mm. When the thickness of the sheet-like fiber assembly (core material) at the time of setting it as a vacuum heat insulating material is set to the thin shape like especially 0.1 mm-5 mm in the said range, the surface formability after vacuum suction improves. In particular, the thickness is in the range of about 0.5 mm to 3.5 mm, which is balanced in terms of heat insulation and productivity. In the measurement of the core thickness (after vacuum suction), the thickness of the outer cover material is very small and shall not be considered.

The sheet-like fiber aggregate may be a single layer sheet, but when the vacuum insulation made of a single layer sheet of polyester fiber is about 5 mm or thicker, it is difficult to manufacture a sheet, and thus the laminated sheet fiber in which two or more layers are laminated It is preferable to use an aggregate (core material). The fiber aggregate is preferably processed without using another material such as a binder, and is made to be processed into a sheet by, for example, a so-called needle punching method. In the chemical bonding method using a binder, a decrease in heat insulation with outgassing occurs over time. In the fiber aggregate using the needle punching method, the sliding characteristics between the fibers are also good and the surface formability is more excellent. On the other hand, the needle punching method refers to a polyester fiber mass in which fibers are oriented to a certain direction, that is, to a polyester fiber web, by punching a plurality of needles with hooks vertically and oppositely, thereby allowing fibers in the web to mutually cross each other. It is a method of forming a sheet by entanglement.

If the average fiber diameter of the polyester fiber is too small, the needle punching machine cannot be used. Therefore, the needle punching machine is used as it is, or it is shaped into a sheet by a chemical bonding method, and the above-described problem occurs. On the other hand, when an average fiber diameter is too big | large, there exists a tendency for heat insulation to fall, and in order to ensure favorable heat insulation, it is necessary to make it high density, and weight becomes a problem.

When other organic fibers, such as polyethylene fiber, are used instead of polyester fiber, the time-dependent fall of the heat insulation by outgas generation will arise.

In this specification, polyester fiber means the fiber which consists of a polymer which a chemical structural unit mainly couple | bonded with an ester bond, and a manufacturing method is not specifically limited. For example, the polyester fiber obtained by reaction of a dicarboxylic acid component and a diol component may be sufficient, or the polyester fiber obtained by reaction of the hydroxycarboxylic acid components which have a hydroxyl group and a carboxyl group in 1 molecule may be sufficient.

Specific examples of the polyester fibers include polyethylene terephthalate (PET) fibers, polybutylene terephthalate (PBT) fibers, polypropylene terephthalate fibers, polyallylate fibers and the like. For example, PET fiber is obtained by the reaction of terephthalic acid dimethyl (DMT) and ethylene glycol (EG) or terephthalic acid (TPA) and EG, and the PBT fiber is made of DMT and tetramethylene glycol (TMG) or TPA. Obtained by reaction of TMG or the like. In addition to sheet-like shaping, mass productivity, and cost, polyethylene terephthalate fibers are preferable. Naturally, there is no problem even when using recycled PET fibers.

Although polyester fiber is not specifically limited, The thing of the softening point about 200-260 degreeC, and about 0.3-1.2 GPa of strength is preferable from a viewpoint of the ease of fiber manufacture.

As a method of fiberizing polyester, there exist melt spinning method, wet spinning method, dry spinning method, etc., Preferably it is melt spinning method. The melt spinning method is a method in which a melt of a polymer is discharged into air from a pore nozzle, cooled and solidified with air while the discharged molten sand is refined, and then drawn at a constant speed thereafter. . In this method, the polyester fiber which has the said fiber thickness can be manufactured easily.

The preferred fiber length (average fiber length) of polyester fiber is 10 to 150 mm. If it is less than 10 mm, it will become difficult to process into a sheet form. When it exceeds 150 mm, heat insulation tends to decrease. Preferably, it is 20 to 80 mm.

The content of the polyester fibers in the fiber aggregate is not particularly limited as long as the object of the first invention is achieved, and is usually 50% by weight or more, based on the total amount of the core material, from the viewpoint of preventing the time-dependent reduction of the thermal insulation caused by the outgas generation. Preferably 90 to 100% by weight. It is most preferable that a core material consists only of polyester fiber from a viewpoint of further improving heat insulation.

Other fibers that may be contained in the fiber aggregate together with polyester fibers, such as polyethylene fibers, polypropylene fibers, acrylic fibers, aramid fibers, nylon fibers, polyvinyl alcohol fibers, fluorine fibers, polyurethane fibers, polynosic Synthetic fibers such as fibers and rayon fibers, inorganic fibers such as alumina and potassium titanate, and natural fibers such as hemp, silk, cotton and wool.

In the first invention, the density of the core material of the first embodiment is preferably 100 to 450 kg / m ³ , particularly 100 to 300 kg / m ³ , and more preferably 150 to 300 kg / m ³ . When density is too small, there exists a tendency for the intensity | strength as a core material to fall, and heat insulation property to fall. On the other hand, when too large, it will become heavy and there exists a tendency for heat insulation to fall. That is, even if the density is too light or too heavy, the heat insulating property tends to be lowered. In the average fiber diameter, the most preferable density is 170 to 270 kg / m ³ , in particular 180 to 250 kg / m ³ .

In this specification, the density of a core material measures the density after accommodating a core material in an outer cover material, and vacuum-sucking. That is, after preparing a vacuum heat insulating material, the weight of a core material is obtained by subtracting the weight of the outer envelope material, gas adsorption material, etc. which were measured previously from the weight of a vacuum heat insulating material. In addition, the volume of the core material is obtained by subtracting the volume of the gas adsorbent or the like measured in advance from the volume of the vacuum insulator. On the other hand, since the outer cover material is very small in thickness, it is not considered for volume calculation. The density is calculated from the weight and volume of the core material obtained.

The core material of the second embodiment of the first invention is a sheet-like fiber aggregate containing polyester fibers having a fiber thickness of 1 to 6 denier, preferably 1 to 3 denier, and at least two kinds of polyester fibers having different melting points. Polyester fibers, ie fibers comprising at least, relatively low melting polyester fibers (hereinafter referred to as low melting polyester fibers) and relatively high melting polyester fibers (hereinafter referred to as high melting polyester fibers) It is an aggregate. By using such a core material, the environmental load at the time of manufacture and recycling can be reduced, and also favorable heat insulation can be exhibited. In addition, by using at least two kinds of polyester fibers having different melting points, the fiber aggregate can be processed into a sheet form at a relatively low temperature by thermal bonding, so that the handling of the core material and the outgassing are suppressed. Workability can be improved. In particular, when the thermal bonding method is employed, the surface of the sheet-shaped core material obtained is hardly brushed and the volume is effectively reduced, so that the handleability and workability of the core material are remarkably improved as compared with the conventional fibrous core material. Compared to foam plate core material, it is improved to the level comparable.

Hereinafter, the core material of 2nd Embodiment is demonstrated. In addition, the core material of 2nd Embodiment is the same as the core material of said 1st Embodiment except having used at least 2 type of polyester fiber from which melting | fusing point differs as polyester fiber unless it mentions specially.

In the second embodiment, the melting point T _L of the low melting polyester fiber is not particularly limited as long as the object of the first invention is achieved. The lower melting point side is preferable in consideration of the required amount of heat and productivity in shaping into a sheet form, and the lower melting point side is not preferable in view of heat conduction performance, since the contact area between fibers due to melting becomes smaller. . After all, it is preferable to set the most preferable melting point in consideration of productivity, cost and heat conduction performance. Typically, the low melting polyester fibers have a low melting point of 110 to 170 ° C, preferably 110 to 150 ° C.

The melting point (T _H ) of the high melting point polyester fiber is not particularly limited as long as it is higher than the melting point (T _L ) of the low melting point polyester fiber, but from the viewpoint of productivity, the high melting point polyester fiber is higher than the melting point of the low melting point polyester fiber. More preferably at least 20 ° C. High melting point polyester fibers typically have a high melting point of 240 to 280 ° C, preferably 250 to 270 ° C.

If only the low melting polyester fibers are used without using the high melting polyester fibers, shaping cannot be performed in the sheet form by the thermal bonding method. In other words, the fiber aggregate is melted by heat treatment by the thermal bonding method, resulting in agglomerates of amorphous resin. In addition, when the low melting polyester fiber is not used and only the high melting polyester fiber is used, there is no low melting polyester fiber for the sheet shaping, and thus the sheet-like shaping method that does not use a binder such as the needle punching method is used. Only is allowed, and further improvement of the core material storage performance to an outer cover material, ie, further workability cannot be expected.

As shown in the schematic diagram of Fig. 1, the structure of the fiber is generally a so-called normal structure composed of one component (Fig. 1 (A)), and a composite structure composed of multiple components (Figs. 1 (B) to (F)). ) And mixed structure (Figs. 1 (G) to (H)). The composite structure is a structure in which a plurality of components are each continuous in the longitudinal direction of the fibers, and are bonded to each other in the short fibers. The composite structure is further a two component composite type, so-called core / shell type (Fig. 1 (B)) and side-bye-side (parallel) type (Fig. 1 (C)). And a multi-component complex of two or more components are classified into so-called multiple parallel type (Fig. 1 (D)), multicore type (Fig. 1 (E)), and radial type (Fig. 1 (F)). In the mixed structure, at least one component is dispersed in other components (matrix components) in the form of discontinuous granules or needles in the longitudinal direction of the fiber, and further, the granular mixed type (Fig. 1 (G)) and the needle-shaped mixed type (Fig. 1). (H)).

As long as the low melting polyester fiber contains the polyester having the low melting point, the fiber structure is not particularly limited, and preferably, at least a part of the surface of the fiber is made of the low melting polyester, for example, It has a structure in any one of 1 (A)-(H). More preferred low-melting polyester fibers have a structure in which all of the fiber surface is made of the low-melting polyester, for example, any one of Figs. 1 (A), (B), (E), (G) and (H). Has the structure of. In the case where the low melting polyester fiber has the structure of Figs. 1 (A) to (H), the blank area of Figs. 1 (A) to (H) is made of the above low melting polyester, and the diagonal area is particularly limited. For example, polyester, polyethylene, polypropylene, nylon and the like. At this time, the melting point of the polymer constituting the diagonal region is not particularly limited. On the other hand, the polyester capable of forming the diagonal region is a polyester having a melting point and / or a raw material monomer different from the low melting point polyester.

It is most preferable that the low melting polyester fiber has the core / shell structure of FIG. 1 (B) from the viewpoint of ease of sheet production. At this time, in FIG. 1B, the shell part (blank area) is made of the low melting polyester (preferably PET), and the core part (the diagonal area) is made of the high melting polyester (especially PET). It is preferable to make.

As long as the high melting polyester fiber contains the polyester having the high melting point, the fiber structure is not particularly limited, and preferably, at least a part of the surface of the fiber is made of the high melting polyester, for example, It has a structure in any one of 1 (A)-(H). A more preferable high melting polyester fiber has a structure in which all of the fiber surface is made of the high melting polyester, for example, any one of Figs. 1 (A), (B), (E), (G) and (H). Has the structure of. In the case where the high melting point polyester fiber has the structure of Figs. 1 (A) to (H), the blank area of Figs. 1 (A) to (H) is made of the high melting point polyester, and the diagonal area is particularly It is not limited, for example, made of polyester, polyethylene, polypropylene, nylon and the like. At this time, the melting point of the polymer constituting the diagonal region is not particularly limited. On the other hand, the polyester capable of forming the diagonal region is a polyester having a melting point and / or a raw material monomer different from the high melting point polyester.

It is most preferable that the high melting point polyester fiber has the normal structure of FIG. 1 (A) from a viewpoint of sheet strength. At this time, in FIG. 1 (A), the fiber is composed of only the polyester having the high melting point (preferably PET).

1 (A) to (H) is a circular cross section, although FIG. 1 (A) to (H) shows the fiber structure of any one of a low melting polyester fiber or a high melting polyester fiber, FIG. The cross sections of A) to (H) should not be construed as being limited to circular, but may be, for example, approximately circular, approximately elliptic, approximately star, approximately polygonal, or the like.

In this specification, melting | fusing point uses the value measured using the differential scanning calorimetry apparatus (DSC-7 from PerkinElmer Japan Co., Ltd.). Specifically, by differential scanning calorimetry, the crystal absorbs heat at the melting point and an endothermic peak is detected. The melting point is determined by this endothermic peak. When a fiber consists of two components, melting | fusing point of each component can be measured by extracting each component separately from the said fiber, etc., and supplying it to the said measurement.

In the second embodiment, the fiber thicknesses of the low melting polyester fibers and the high melting polyester fibers can be independently selected within the range of 1 to 6 denier, preferably 1 to 3 denier. When the said fiber band is represented by the average fiber diameter, it respond | corresponds to "9-25 micrometers" and "preferably 9-17 micrometers", respectively.

In addition, the fiber length of the low-melting polyester fiber and the high-melting polyester fiber is not particularly limited, and may be, for example, independently in the range of 17 to 102 mm.

The method for forming the low melting polyester fiber and the high melting polyester fiber can adopt a known method generally known as the method for forming the fiber, and is usually selected depending on the structure of the fiber. For example, when forming a fiber having a normal structure, a so-called melt spinning method, a wet spinning method, a dry spinning method and the like can be employed, but preferably a melt spinning method is adopted. In the melt spinning method, a melt of a polymer having a predetermined melting point is discharged into the air from a pore nozzle, cooled and solidified with air while making the discharged molten yarn fine, and then taken out at a constant speed. In this method, polyester fibers having a fiber thickness of about 1 to 6 denier can be easily produced.

For example, in the case of forming a fiber having a core / shell structure, a polymer inter-array spinning method, a peeling type composite fiber spinning method, a multilayer type composite fiber spinning method, or the like can be employed. A polymer inter-array spinning method is adopted in which a sea) composite fiber is obtained. In the polymer inter-array spinning method, two kinds of fibers having different solubility are used to intermix fibers of sea components and fibers of a small amount of island components and pull them into an iris shape. It is placed in a funnel channel, heated and melted, extruded from the nozzle and concentrated as a single strand of fiber to spin.

The fiber aggregate (core material) containing such a low melting point polyester fiber and a high melting point polyester fiber is normally processed into the sheet form by a thermal bonding method. From the viewpoint of the processability improvement by the thermal bonding method, it is preferable to process a fiber assembly preliminarily into a sheet form by the needle punching method before processing by the thermal bonding method.

In the thermal bonding method, heat and pressure are applied between two rollers to the fiber aggregate, and the low melting polyester portion of the low melting polyester fiber is melted to bond the surfaces of the fibers to form a sheet and Processing. Compared with the needle punching method, the shape retaining property is higher, and the storage property to the outer cover material is remarkably good. In 2nd Embodiment, since a low melting polyester fiber is contained in a fiber assembly, the heating temperature at the time of the said process can be reduced effectively. Therefore, the handleability and workability of a core material can be improved, effectively preventing generation of outgas.

When processing into a sheet form is performed by the chemical bonding method using a low melting point organic binder, for example, recycling property will fall and the heat insulation performance by the outgas will fall.

In the second embodiment, the thickness of such a sheet-like fiber assembly (core material) is not particularly limited as long as the object of the first invention is achieved, and is usually about 1 mm to 50 mm, particularly about 5 mm to 20 mm, when the vacuum insulator is used. You just need In the second embodiment, since the sheet-shaped core material has little napping on the surface and is excellent in handling and workability, it is advantageous for laminating two or more layers of the core material and inserting it into the outer cover material. In addition, the sheet-shaped core material whose thickness is about 50 mm or more under atmospheric pressure is difficult to manufacture. Therefore, it is preferable that the thickness under atmospheric pressure of a sheet-shaped core material is 0.1-20 mm, especially 1-10 mm. Moreover, in 2nd Embodiment, when inserting a core material into an outer cover material, it does not prevent using a sheet-shaped core material by 1 layer alone.

The blending ratio of the low melting polyester fiber and the high melting polyester fiber in the fiber assembly of the second embodiment is from 5:95 to 50:50, particularly from 10:90 to weight ratio, from the viewpoint of further improving heat insulation. It is preferable that it is 30:70.

The total content of the low-melting polyester fiber and the high-melting polyester fiber in the fiber assembly of the second embodiment is not particularly limited as long as the object of the first invention is achieved, and usually the viewpoint of preventing the outgas more effectively. At least 50% by weight, preferably 90 to 100% by weight, based on the total amount of the fiber aggregate. From a viewpoint of further improving heat insulation, it is most preferable that a core material consists only of a low melting polyester fiber and a high melting polyester fiber.

As other fibers which may be contained in the fiber aggregate together with the low melting polyester fibers and the high melting polyester fibers, fibers such as "other fibers" in the first embodiment may be mentioned. Further, the fiber aggregate may contain, as the other fibers, polyester fibers having different melting points and / or raw material monomers from the low melting polyester fibers and the high melting polyester fibers.

In the second embodiment, the density of the core is 100 to 350kg / m ³ and more preferably 150 to 330kg / m ^3. The most preferable density is 200-300 kg / m <^3> .

As long as the outer cover material which accommodates the core material of 1st Embodiment and 2nd Embodiment has gas barrier property and can hold | maintain the inside under reduced pressure, any can be used, Preferably it can heat-seal will be. As a preferred embodiment, for example, a gas barrier film composed of a four-layer structure of nylon, aluminum deposited PET (polyethylene terephthalate), aluminum foil, and high density polyethylene as the innermost layer from the outermost layer; A gas barrier film made of a polyethylene terephthalate resin from an outermost layer, an aluminum foil in an intermediate layer, and a high density polyethylene resin in an innermost layer; The gas barrier film etc. which consist of PET resin in outermost layer, ethylene-vinyl alcohol copolymer resin which has an aluminum vapor deposition layer in an intermediate | middle layer, and high density polyethylene resin in an innermost layer are mentioned. Such envelopes are usually used after being processed into a bag shape, and for example, they are used by heat-sealing three sides leaving an opening. On the other hand, the envelope material of this embodiment is used so that the innermost layer constitutes the back surface, that is, the innermost layer constitutes the inside of the bag.

In the vacuum insulator of the first aspect of the invention, a vacuum insulator having excellent heat insulating properties can be obtained only by placing only a core material in the outer cover material. However, in view of further improving heat insulation over time, a gas generated inside the vacuum insulator after vacuum suction, for example, It is preferable to accommodate together the core material the gas adsorbent which adsorbs outgas and water which generate | occur | produce from a core material, and the gas and water which invade from the outside.

The gas adsorbent may be used as it is in the form of powder, granules or tablets, but from the viewpoint of handling, the gas adsorbent is preferably used in a form accommodated in a breathable container.

Although it does not specifically limit as a gas adsorption substance, As physically adsorbing gas, water, etc., activated carbon, a silica gel, aluminum oxide, molecular sieve, zeolite etc. are mentioned, for example. Examples of chemically adsorbing gas, water, and the like include calcium oxide, barium oxide, calcium chloride, magnesium oxide, magnesium chloride, metal powder materials such as iron and zinc, barium-lithium alloys, zirconium alloys, and the like. Can be.

The breathable container in which the gas adsorption substance is accommodated is not particularly limited as long as the object of the first invention is achieved, and for example, hard containers such as metal containers and plastic containers, paper bags, film bags, and organic materials Soft bags, such as a fiber nonwoven fabric bag, are mentioned. If the air permeability of the container is too small, the gas inside the container is difficult to escape to the outside during the manufacture of the vacuum insulator, and the time for evacuation by the vacuum pump becomes long. Larger is preferable in the range which is not received.

It is preferable that a gas adsorption material is accommodated in a soft bag from a viewpoint of the curability of a vacuum heat insulating material, especially when a core material is thin as mentioned above. Specific materials constituting the soft bag include, for example, paper, porous polyethylene film, porous polypropylene film, polyester fiber nonwoven fabric, polyethylene fiber nonwoven fabric, nylon fiber nonwoven fabric, and the like. It is a terephthalate fiber nonwoven fabric. It is because it is a polyester fiber core material which is a preferable material as a core material, especially a polyethylene terephthalate fiber core material, and a copper material, and its hygroscopicity of the material itself is small and workability at the time of curved surface processing is very good. Per unit area of the nonwoven fabric constituting the turret weight (basis weight) it is preferably from the viewpoint of operation-maintenance and vacuum process of the gas absorption material 30 to 200g / m ^2, particularly from 35 to 130g / m ^2.

Polyester fiber and polyethylene terephthalate fiber which preferably comprise the bag of a gas adsorption material are the same as the polyester fiber and polyethylene terephthalate fiber which can comprise a core material, respectively.

Preferable 1 Embodiment is described below about the manufacturing method of the vacuum heat insulating material of 1st invention.

The fiber aggregate is molded into a sheet by needle punching or the like to obtain a core material. When using low-melting polyester fibers and high-melting polyester fibers, they are uniformly mixed, the fibers are oriented to some extent in one direction, and then molded into a sheet by needle punching method first, followed by thermal bonding. The core material is obtained by molding into a sheet having a rigid dimensionally-stable shape. The obtained core material is cut into an appropriate size and shape (for example, square), and dried to remove moisture and the like contained therein. Although the said drying is normally performed on condition of about 1 hour at 120 degreeC, it is preferable to vacuum-dry at 120 degreeC in order to remove water etc. of a polyester fiber more effectively. In particular, when using low-melting polyester fibers and high-melting polyester fibers, drying is at a temperature of 100 ° C. or higher and below the melting point (T _L ) of the low melting polyester fibers, preferably T _L -10 to T _L −. Although carried out under a condition of about 1 hour at a temperature of 5 ° C., for example, 100 to 105 ° C., in order to more effectively remove moisture and the like of the polyester fiber, vacuum drying at the above temperature is preferable. Regardless of the type of fiber, the drying may be combined with far-infrared drying, and the degree of vacuum is preferably about 0.5 to 0.01 Torr.

Next, the core is inserted into the outer envelope sealed in a bag shape. In this case, the gas adsorbent may be inserted together. Although the insertion position of a gas adsorption material is not specifically limited, From a viewpoint of surface smoothness, the thickness of the core material in the insertion position of a gas adsorption material can be made thinner than the periphery. It is put in a vacuum suction apparatus in this state, and it evacuates under reduced pressure so that internal pressure may be a vacuum degree of about 0.1-0.01 Torr. Thereafter, the bag-shaped opening of the outer cover material is sealed by heat fusion to obtain a vacuum insulator. On the other hand, the core material density can also be controlled by press working at room temperature in order to adjust the core material thickness.

(2nd invention)

The vacuum insulator of the second invention is the vacuum insulator of the first invention, characterized in that a seal portion formed by fusion of the outer surface of the outer cover material is provided at the peripheral portion of the outer cover material and the inner region of the peripheral edge portion. That is, the vacuum heat insulating material of 2nd invention is the same as that of the vacuum heat insulating material of 1st invention except having the sealing part which the back surface of the outer wrapper material fused together unless it mentions specially in the peripheral part of the outer wrapper and the said inner peripheral part. Hereinafter, although 2nd invention is demonstrated, the description similar to 1st invention is abbreviate | omitted.

Specifically, the vacuum insulator of the second invention comprises at least a core material and an outer material which accommodates the core material and maintains the inside in a reduced pressure state, and a seal portion in which the outer surfaces of the outer material are fused together (hereinafter, simply The " seal portion " in the periphery of the outer cover and in the inner region of the periphery. In the second aspect of the present invention, the inner region of the outer periphery of the envelope means an area enclosed by the seal portion formed on the periphery of the envelope. For example, the region enclosed by the seal portions 3A, 3B, 3C, and 3D in FIG. In FIG. 4A, the region surrounded by the seal portions 13A, 13B, 13C, and 13D, and in FIG. 6A, the region surrounded by the seal portions 23A, 23B, 23C, and 23D are meant.

For example, the vacuum insulator shown in the schematic aiming drawing of FIG. 2A has a seal part in the peripheral part 3A, 3B, 3C, and 3D of the outer cover material 2, and the inner region 3E of the said peripheral part. That is, the vacuum insulator of FIG. 2 (A) has a through hole 3F (an oblique line region formed by dashed lines), and at the same time the peripheral portion 3A, 3B, 3C and 3D of the outer covering material and the inner circumferential portion 3E of the through hole. Accordingly, the outer surface of the envelope is sealed. In particular, the vacuum insulator of FIG. 2 (A) has a through hole 3F (an oblique line region formed by dashed lines), and a seal portion 3E is formed along the vacuum insulator side inner circumference of the through hole 3F. . In addition, the area | region 3F shows the area | region of the part cut out of the seal part 3G formed. FIG. 2 (B) is a schematic cross-sectional view of the I-I cross section of the vacuum insulator of FIG. 2A, wherein 1 represents a core material and a divalent outer cover material.

For example, the vacuum heat insulating material shown in the schematic aiming drawing of FIG. 4 (A) has a seal part in the peripheral part 13A, 13B, 13C, and 13D of the outer packaging material 12, and the inner region 13E of the said peripheral part. That is, the vacuum heat insulating material of FIG. 4 (A) has notch 13F (dashed line region made of dashed lines), and the peripheral portions 13A, 13B, 13C, and 13D of the outer covering material and the inner peripheral part 13E of the notch. Accordingly, the outer surface of the envelope is sealed. In particular, the vacuum insulator of FIG. 4 (A) has a cutout portion (the entire dashed line region of the dashed line), and a seal portion 13E is formed along the vacuum insulator side inner circumferential portion of the cutout 13F. In addition, area | region 13F shows the area | region of the part cut out of the seal part 13G formed. Fig. 4B is a schematic sectional view taken along the line II-II of the vacuum insulator of Fig. 4A, wherein 11 represents a core material and 12 represents an outer covering material.

In addition, for example, the vacuum heat insulating material shown to the schematic aiming drawing of FIG. 6 (A) has a seal part in the peripheral part 23A, 23B, 23C, and 23D of an outer cover material, and the inner region 23E of the said peripheral part. That is, in the vacuum insulator of FIG. 6 (A), two or more core materials are accommodated in the outer cover material, and at the same time, the peripheral portions 23A, 23B, 23C and 23D of the outer cover material and the outer peripheral parts 23A, 23B, 23C, 23D and 23E of the core material. The outer surface of the envelope is sealed along). In particular, the vacuum insulator of FIG. 6 (A) forms a bent groove for the seal portion 23E to bend and use the vacuum insulator, and has a bending function by the groove. FIG. 6 (B) is a schematic sectional view taken along the line III-III of the vacuum insulator of FIG. 6 (A), wherein 21 represents a core material and 22 represents an outer covering material.

As the core materials 1, 11, 21 which concerns on 2nd invention, the same thing as the core material which concerns on 1st invention is preferable. The second invention does not prevent the core material from containing inorganic fibers such as glass fibers (glass wool), alumina fibers, slag wool fibers, silica fibers, and rock wool.

In the second invention, when the through hole or the cutout is formed, a portion corresponding to the through hole or the cutout is also formed in the core material. In addition, the said part may be previously formed as a sheet-like fiber assembly core material, and the through-hole part or the notch part may be formed at the time of insertion into an outer cover material. The position at which the through-holes and cutouts are formed is appropriately determined according to the use of the vacuum insulator to be obtained, and the shapes and dimensions of the through-holes and the cutouts are their uses, that is, the wirings to pass through the through-holes, It can determine suitably according to the cross-sectional shape, size, etc. of an apparatus, etc., and the shape and size of the part using a notch. The shape of the through hole is usually a polygon such as a circle, a square, a hexagon, etc., but in order to prevent the occurrence of wrinkles in the outer material, the through hole and the cutout portion are preferably close to a circle, for example, forming a rectangular through polygonal through hole. Even in this case, it is preferable to chamfer the curved portions of each corner portion.

In the second invention, the thickness of the core material is not particularly limited as long as the object of the second invention is achieved, and is usually about 0.1 to 50 mm, especially about 0.3 to 20 mm, and preferably about 0.5 to 5 mm when the vacuum insulator is used.

One preferable embodiment of the manufacturing process of the vacuum heat insulating material of 2nd invention is demonstrated below using FIG. 2, FIG. 4, and FIG. 2 (A) and (B) are schematic plan views and cross-sectional views of the vacuum insulator of the second invention each having a through hole. 4 (A) and (B) are schematic plan views and cross-sectional views of the vacuum insulator of the second invention having a cutout. 6A and 6B are schematic plan views and cross-sectional views of the vacuum insulator of the second invention having a plurality of core materials.

The fiber aggregate is molded into a sheet by needle punching or the like to obtain a core material. The obtained core material is cut into an appropriate size and shape (for example, a square), and in the case of a through-work, a penetrating portion is formed in the core material itself, and in the case of a cutout product, a cutout is formed in the core material itself. Both through holes and cutouts may be formed. Subsequently, drying is performed in order to remove the water | moisture content contained inside. As in 1st invention, drying can also use together the drying by far-infrared rays, and can also vacuum-dry, and the drying conditions are the same as the drying conditions of the core material in 1st invention.

Next, the core material 1, 11, or 21 is inserted into a bag shape, that is, three sides of the periphery portions 3A to 3C, 13A to 13C, 23A to 23C, and sealed outer material 2, 12, or 22. . On the other hand, if a plurality of core materials 21 are used, a plurality of core materials 21 are inserted. Also, if necessary, gas adsorbents are inserted together. It is put in a vacuum suction apparatus in this state, and it evacuates under reduced pressure so that internal pressure may be a vacuum degree of about 0.1-0.01 Torr. Then, the bag-shaped opening part which is the peripheral part unsealed part of an outer cover material is sealed by heat fusion. On the other hand, the seal of the periphery 3D, 13D, or 23D of the outer cover material is a seal for maintaining the decompression state after vacuum evacuation, and the seal width, the seal position, and the like are preferably set in a range capable of maintaining the decompression state. Do. For example, if the core thickness after vacuum evacuation is about 0.5 to 15 mm, the seal width is preferably about 5 to 30 mm. Moreover, in order to make a seal easy, if a seal part is formed inward from a outermost edge part by leaving a margin part, a seal defect will hardly occur and workability will improve. The marginal portion may be used as it is bent at the time of use, or may be cut out.

Regarding the through-hole and the missing article, along the inner circumferential portion 3E or 13E of the through-hole 3F and / or the cut-out portion 13F, or the inner circumferential portion and the through-hole 3F and / or the cut-out portion ( With respect to the front surface 3G or 13G with 13F), the back surface of outer packaging material is sealed by heat press etc. If it is a some core material, along the outer peripheral part 23E of each core material, the back surface of outer packaging materials will be sealed by heat press etc. Then, about the through-work and the missing article, the outer cover material is cut out with a cutter etc. in the state which left said sealed inner peripheral parts 3E and 13E, and the vacuum which has the through-hole part 3F or the notch part 13F is carried out. Get insulation. On the other hand, the inner peripheral parts 3E and 13E may be left to such an extent that the decompression state after vacuum evacuation can be maintained, and what is necessary is just to set suitably in the range which can maintain a reduced pressure state about the width | variety of the sealed inner peripheral part. After completion of the vacuum insulator, it may be pressed if necessary, the thickness of the core can be adjusted, and the density can be controlled.

The vacuum insulator of the second invention can be produced by a method comprising the following steps;

(a) storing the core material in a bag-shaped envelope;

(b) sealing the openings of the bag-shaped envelopes by press-contacting the heating member in a state in which the bag-shaped envelope is evacuated; And

(c) A step of forming a seal portion in the inner region of the outer periphery of the envelope material by heating the core material housing envelope with the opening sealed.

Hereinafter, each process is explained in full detail.

Step (a);

In this step, the predetermined core material is stored in the bag-shaped envelope from the opening.

For example, when manufacturing the vacuum heat insulating material which has the through hole part 3F as shown in FIG. 2, as shown to FIG. 3 (A), the core material 1 which has the through hole part 5 is used, and the said core material is used. (1) is accommodated in the bag-shaped outer package material 2 from an opening part.

For example, when manufacturing the vacuum heat insulating material which has a notch as shown in FIG. 4 (the whole dotted line area | region), as shown to FIG. 5 (A), the core material 11 which has the notched part 15 The core member 11 is stored in the bag-shaped envelope 12 from the opening.

For example, when manufacturing the vacuum heat insulating material which has the bending groove part 23E as shown in FIG. 6, as shown to FIG. 7 (A), it uses the 2 or more divided core material 21, and the said core material ( 21 is accommodated in the bag-shaped outer packaging material 22 from an opening part, and it arranges in parallel.

In this step, the core material is preferably dried. As in 1st invention, drying may use together the drying by far-infrared radiation, and you may vacuum-dry, and the drying conditions are the same as the drying conditions of the core material in 1st invention.

Step (b);

In this process, in the state which evacuated the inside of the bag-shaped envelope material which accommodated the core material, the opening part of this bag-shaped envelope material is sealed by pressure welding of a heating member. As a result, the adsorption | suction part of the back surface of a cover material is formed in the inner region of a cover material peripheral part, and obtains the vacuum heat insulating material as shown, for example in FIG. 3 (B), FIG. 5 (B) and FIG. 7 (B).

In detail, in FIG. 3 (B), in the region 6 corresponding to the through hole of the core material, the outer cover materials are physically adsorbed to each other by pressure reduction, and such an adsorption portion 6 is subjected to the subsequent step (c). ), The seal portion is formed.

In FIG. 5 (B), in the region 16 corresponding to the cutout portion of the core material, the outer envelope materials are physically adsorbed to each other by pressure reduction, and such an adsorption portion 16 is fused at a later step (c). Thus, the seal portion is formed.

In FIG.7 (B), in the area | region 26 between a core material and a core material, the outer cover materials are physically adsorb | sucking with each other by pressure reduction, and such an adsorption | suction part 26 fuse | bonds and seals in the following process (c). The addition is formed.

The internal pressure of the outer cover material at the time of the opening seal is not particularly limited as long as the adsorption portion can be fused by simple heating in the subsequent step (c), and usually 0.05 Torr or less, particularly 0.01 to 0.005 Torr, is suitable. If the internal pressure is too large, the outer cover material does not sufficiently adsorb the back surfaces, so that even if simple heating is performed in step (c), the seal portion is not formed.

The heating member for forming the seal portion of the opening is not particularly limited as long as it can achieve pressure welding to the opening, and examples include a heating block, a jig to which ultrasonic vibration is applied, a jig to which a high frequency magnetic field is applied, and the like. have.

The temperature, the pressing force, and the pressing time of the heating member are not particularly limited as long as the sealing of the opening can be achieved.

Step (c);

In this process, only the core material storage outer cover material with which the opening part was sealed is heated. That is, the adsorption part of the back surface of the outer cover material formed in the previous process (b) is fused by simple heating, and a seal part is formed.

For example, in FIG. 3B, the adsorption part 6 is fused, and as a result, a seal part is formed in the through hole of the core material. The seal part formed at this process is shown as area | region 3G in FIG.2 (A).

Also, for example, in FIG. 5B, the adsorption portion 16 is fused, and as a result, a seal portion is formed in the cutout portion of the core material. The seal part formed at this process is shown as area | region 13G in FIG.4 (A).

Also, for example, in FIG. 7B, the adsorption portion 26 is fused to form a seal portion between the core material and the core material as a result. The seal part formed at this process is shown as area | region 23E in FIG. 6 (A).

The heating means is not particularly limited as long as the temperature can be raised to a predetermined temperature. Usually, an oven, a hot air circulation dryer, or the like is used.

The heating temperature and the heating time are not particularly limited as long as the adsorption portions of the back surfaces of the outer cover material can be fused. What is necessary is just to add the temperature more than melting | fusing point of a sealing layer (the innermost layer of an outer cover material), for example, and heating temperature is 5 degreeC or more higher than melting | fusing point of a sealing layer preferably. Heating time is suitable, for example, for 1 to 120 seconds, particularly for 10 to 60 seconds.

When manufacturing the vacuum heat insulating material which has a through-hole and / or a cutout part, the following process (d) is further included.

Step (d);

In this step, the seal portion (an oblique line region in dotted lines in Figs. 2A and 4A) in the through hole and / or the cutout portion of the core material is formed around the seal portion (Fig. 2A). 3E and 13E of FIG. 4 (A) are cut out, and the through-hole part and / or the cutout part are formed in a vacuum heat insulating material.

When manufacturing the vacuum heat insulating material of 2nd invention, after sealing the opening part of a cover material in the state which evacuated the inside of a cover material as mentioned above, the seal part 3G, 13G, or 23E of the inner side part of a cover material peripheral part was removed. When it forms by simple heating, especially oven heating, the effect shown below is acquired. The pressure contact is sufficient only once to form the seal portion of the opening, and furthermore, the heating member for the pressure contact does not need to be processed into a complicated shape, so that the vacuum insulator can be easily manufactured. Further, even when the seal portion formed in the inner region of the peripheral portion of the vacuum insulator has a relatively complicated shape, the seal portion can be formed by simple heating, such a vacuum insulator can be easily manufactured.

(Third invention)

The vacuum heat insulating material of 3rd invention WHEREIN: The vacuum heat insulating material of 1st invention WHEREIN: The inner material which accommodated the core material is accommodated in an outer wrap material in a reduced pressure state, It is characterized by the above-mentioned. That is, the vacuum heat insulating material of 3rd invention is the same as the vacuum heat insulating material of 1st invention except the core material accommodated and used unless it mentions specially. Hereinafter, although 3rd invention is demonstrated, the description similar to 1st invention is abbreviate | omitted.

In detail, the vacuum heat insulating material of 3rd invention comprises at least a core material, the inner material which accommodates the said core material, and the outer material which accommodates the said inner material and can maintain an inside under reduced pressure.

As a core material in 3rd invention, the same thing as the core material in 1st invention is preferable.

The form of the fiber aggregate as the core member in the third invention is not particularly limited, and may be, for example, sheet or cotton. By making it into a sheet form, the handleability and workability of a core material further improve, and also the environmental load at the time of manufacture and recycling can be reduced more, and also the heat insulation of a vacuum heat insulating material improves more. By setting it as a shape, the objective of 3rd invention can be achieved more effectively. Conventionally, when the cotton-fiber aggregate is used, the inside of the envelope can not be kept at a reduced pressure due to scratches on the envelope or adhesion of the core to the opening of the envelope, so that the yield of the vacuum insulator is lowered, or the insulation of the core is uneven. Although it is easy to fall, in the 3rd invention, even when using a cotton core material, such a problem can be prevented effectively.

"Smooth shape" refers to a so-called cotton-like state, and means a form in which fibers are irregularly entangled and integrated. Sheet-like shapes, such as a so-called web shape and needle punching process shape, which are formed by floating the surface, are not included.

The inclusion material is not particularly limited as long as it can accommodate the core material, and preferably has a form having breathability. As such a form, the film which has a ventilation hole in at least one part, and a woven fabric, a knitted fabric, a nonwoven fabric, etc. are mentioned, for example. The size of the hole of the film and the weight per unit area of the woven fabric, the knitted fabric and the nonwoven fabric are not particularly limited as long as the core material does not scatter from the inclusion material due to the reduced pressure exhaust during manufacture of the vacuum insulation material, and the inside of the inclusion material can be decompressed smoothly. . 3rd invention does not exclude using the thing of the film form which does not have air permeability as an inclusion material. By using the inclusion material which does not have air permeability, the inside of the inclusion material can be kept at a reduced pressure with the inclusion material alone.

The material of the inclusion material is not particularly limited as long as the object of the third invention can be achieved, and examples thereof include polyester, polypropylene and nylon. The polyester agent is preferable from the viewpoint of outgas generation, and from the viewpoint of recycling property, it is most preferable to use PET as the material for both the core material and the inclusion material. Moreover, from a viewpoint of core material drying at the time of vacuum insulation material manufacture, it is preferable to use a material whose melting | fusing point is 100 degreeC or more, especially about 100-300 degreeC.

For example, the woven fabric, knitted fabric, and nonwoven fabric made of polyester as the inclusion material may be made of polyester fibers as described above as the core material in the first invention.

It is preferable to enclose a gas adsorption material in the vacuum heat insulating material of 3rd invention from a viewpoint of further improving heat insulation with time similarly to 1st invention. In the third invention, the gas adsorbent is disposed between the envelope and the envelope or in the envelope. Preferably, a dent corresponding to the size of the gas adsorbent may be formed in the core inside the inclusion material, and the gas adsorbent may be disposed directly in the pit, and the gas adsorbent may be disposed at the position of the pit above the inclusion material. It may be. The gas adsorbent may be housed in a hard container having air vents, or may be housed in a soft container having air permeability (eg, a bag made of nonwoven fabric).

Preferred embodiment of the manufacturing method of the vacuum heat insulating material of 3rd invention is demonstrated below.

First, a core of a predetermined form is inserted into a bag-shaped breathable inclusion material. At this time, the gas adsorbent may be inserted into the inclusion material together with the core material. In the case where the core is in the form of a sheet, two or more cores may be overlapped and inserted into the inclusion material. The bag-shaped inclusion material should have an opening part, for example, what laminated | stacked the three sides by overlapping two rectangular pieces of envelope material. Bonding depends on the material of the inclusion material and may be achieved by, for example, heat fusion, or by embroidery.

Next, the opening part of the inner bag which accommodated the core material is sealed. At this time, it is preferable to seal while securing a predetermined core material thickness by a jig such as a press. By press, the surface smoothness of a vacuum heat insulating material improves, for example, the workability at the time of sticking to the inner surface of a refrigerator box body improves, and heat insulation further improves. In addition, it is preferable to provide not only a pressure but a heat at the time of a press. This is because by providing heat and pressure, the surface smoothness of the vacuum insulator is further improved, and excellent heat insulation can be easily ensured. It is more preferable to apply heat at the time of pressing, especially when using a cotton-like thing as a fiber aggregate of a core material. The temperature at the time of pressing is 30-100 degreeC, especially 35-85 degreeC.

Sealing of the inclusion opening may be achieved by thermal fusion or by embroidery.

After accommodating the core material in the inner bag and sealing the opening, the obtained inner bag is inserted into the outer bag member on the three sides heat-sealed. At this time, the gas adsorbent may be inserted together. In addition, it is also possible to insert two or more nesting materials containing the core material into the outer packaging material.

The outer cover material in which the inner cover material is accommodated is transferred into the vacuum suction device in an open state, and is evacuated under reduced pressure so that the internal pressure is about 0.1 to 0.01 Torr. Thereafter, the opening of the outer cover material is sealed by heat fusion to obtain a vacuum insulator.

The vacuum insulation may be press processed at room temperature to adjust core thickness and core density.

From a viewpoint of further improving heat insulation, it is preferable to dry a core material before sealing of an outer cover material opening part. In detail, drying may be performed just before inserting the inner material which accommodated the core material, and the opening part was sealed in the outer material, or after inserting it to the outer material, and performing it in the state inserted in the outer material before decompression-ventilating. You may. As in 1st invention, drying may use together the drying by far-infrared rays, and may vacuum-dry, and the drying conditions are the same as the drying conditions of the core material in 1st invention.

In the case of using a non-breathable inclusion material, the core material is placed in a vacuum suction device with the core material inserted into a bag-shaped inclusion material, and the pressure opening is carried out under reduced pressure so that the internal pressure is about 0.1 to 0.01 Torr. Seal by fusion. Preferably, while depressurizingly evacuating, the above predetermined core thickness is ensured by a jig such as a press. Thereby, the inclusion material which accommodated the core material in the pressure reduction state inside can be obtained. In this case, the bag-shaped inclusion material may have an opening, and the inside may be kept in a reduced pressure state by sealing the opening in a reduced pressure state. For example, two rectangular inclusions may be stacked to thermally seal three sides. have. Regarding the core material drying in this case, it is preferable to accommodate the core material and to dry the inclusion material in which the opening part is unsealed before evacuating under reduced pressure. After obtaining the inner material which accommodated the core material in pressure reduction inside, it inserts into an outer material similarly to the case where the air permeable inner material is used, and what is necessary is just to seal an outer part opening part under reduced pressure.

Experimental Example A

<Fiber used for core material>

The polyester fiber of Table 1 was used. All of the polyester fibers were polyethylene terephthalate fibers having a fiber length of 51 mm.

<Example A1>

The polyester fiber of Table 1 was processed into the sheet form by the needle punching method. The weight per sheet unit area immediately after the processing was 550 g / m ² . The sheet was cut into a size of 200 mm × 200 mm, and dried at a temperature of 120 ° C. for 1 hour. Four sheets of dried sheets were laminated, and the laminated sheets were inserted into a gas barrier film envelope made of a four-layer structure of nylon, aluminum vapor-deposited PET, aluminum foil, and high-density polyethylene as a core material, and at the same time, a gas absorbent material Saes Getters Japan Co., Ltd. product: C0MB0) was inserted into one envelope. Thereafter, vacuum suction was performed in a vacuum suction device so that the internal pressure was 0.01 Torr and sealed by thermal fusion. The obtained vacuum heat insulating material was 200 mm x 200 mm in size, and was 10 mm in thickness. The density of the core material of the obtained vacuum heat insulating material was 220 kg / m <^3> .

<Methods of Examples A2 to A8 and Comparative Examples A1 to A2>

A vacuum insulator was obtained in the same manner as in Example A1 except that the type and amount of fibers used for the core material were changed as described in Table 1. On the other hand, in Comparative Example A2, the cotton fiber was used as it was without processing into a sheet.

<Comparative Example A3>

Using continuous foam polyurethane foam, it cut into 200 mm x 200 mm x 10 mm first. The core material was dried at a temperature of 120 ° C. for 1 hour. After drying, it inserted into the same outer cover material as Example A1, and simultaneously inserted the gas adsorption material into one outer cover material. Thereafter, vacuum suction was performed in a vacuum suction device so that the internal pressure was 0.01 Torr and sealed by thermal fusion to obtain a vacuum heat insulating material.

Initial Insulation

Evaluation of initial stage thermal insulation was performed by measuring the thermal conductivity of 20 degreeC of average temperature using "Auto (lambda) HC-074" (made by EKO Instruments Co., Ltd.). In addition, the measurement was measured after 1 day passed in a vacuum suction process.

<Long term insulation>

Long-term heat insulation evaluation puts the vacuum heat insulating material which evaluated the initial heat insulation into the 70 degreeC thermostat, and it is taken out after 4 weeks, and average temperature is 20 degreeC using "Auto (lambda) HC-074" (made by Eco-Co., Ltd. product). It carried out by measuring the thermal conductivity of.

<Workability>

The workability at the time of inserting a fiber aggregate into an outer cover material was evaluated according to the following criteria.

○; Fiber assemblies can be easily inserted into the envelope;

×; The core material is soft and the fiber aggregate cannot be evenly inserted in the envelope.

Experimental Example B

<Production of Gas Absorber>

Gas adsorbent A;

^Two PET nonwoven fabrics (size 50mm x 100mm) per unit area consisting of polyethylene terephthalate fibers having an average fiber thickness of 1.5 deniers and an average fiber length of 51 mm were piled up to seal three sides. 10 g of gas adsorption substance was put in it, the opening part was sealed, and gas adsorption material A was obtained.

Gas adsorbent B;

A gas adsorbent B was obtained by the same method as the gas adsorbent A, except that a PET nonwoven fabric having a weight of 60 g / m ² per unit area was used.

Gas adsorbent C;

A gas adsorbent C was obtained by the same method as the gas adsorbent A, except that a PET nonwoven fabric having a weight of 150 g / m ² per unit area was used.

Gas adsorbent D;

^Two PP nonwoven fabrics (size 50mm x 100mm) per unit area consisting of polypropylene fibers having an average fiber thickness of 0.5 denier and an average fiber length of 51 mm were piled up to seal three sides. 10 g of gas adsorption substance was put in it, and the opening part was sealed and the gas adsorption material D was obtained.

<Example B1>

The fiber of Table 2 was processed into the sheet form by the needle punching method. On the other hand, the fiber thickness of PET fiber is 1.5 denier. The sheet was cut into a size of 500 mm × 500 mm, and dried at a temperature of 120 ° C. for 1 hour. The sheet after drying was inserted into the gas barrier film outer cover material which consists of a four-layered structure of nylon, aluminum vapor-deposited PET, aluminum foil, and high density polyethylene as a core material, and the gas adsorption material A was inserted in one outer cover material at the same time. Thereafter, vacuum suction was performed in a vacuum suction device so that the internal pressure was 0.01 Torr and sealed by thermal fusion. The vacuum insulator obtained was 500 mm × 500 mm in size and 1 mm in thickness. The density of the core material of the obtained vacuum heat insulating material was 220 kg / m <^3> .

<Examples B2 to B5, Comparative Example B1 and Reference Example B1>

A vacuum insulator was obtained in the same manner as in Example B1 except that the kind of fibers used for the core material, the average fiber diameter, the kind of the gas adsorbent, and the like were changed as described in Table 2.

<Insulation>

The heat insulation was evaluated by the same method as the initial heat insulation in Experimental example A. FIG.

<Curvability>

The obtained vacuum heat insulating material was wound up on the cylindrical plastic pipe of diameter 150mm and length 600mm. The ease of winding up of the vacuum heat insulating material at that time, and the adhesiveness with the piping were evaluated.

◎; It is easy to wind up and the adhesion degree is also good;

○; It is hard to wind slightly, but adhesion is good;

×; It is hard to wind up, and adhesion is bad, too.

Experimental Example C

<Fiber used for core material>

The following polyester fiber was used.

Polyester fiber A (normal structure (PET), fiber thickness 1.5d, fiber length 51mm, melting point of PET 260 degrees Celsius)

Polyester fiber B (core / shell type structure (core part and shell part; PET), fiber thickness 2d, fiber length 51mm, core part: PET melting point 260 degreeC (PET), shell part: PET melting point 120 degreeC (PET))

<Example C1>

The fiber of Table 3 was processed into the sheet form by the needle punching method and the thermal bonding method according to the following method. Specifically, using 90% by weight of polyester fiber A and 10% by weight of polyester fiber B, these blended surfaces were preliminarily sheet-formed by the needle punching method, and then heat-treated at 120 ° C. by a thermal bonding method, A sheet core material was obtained. The weight per sheet unit area immediately after the processing was 550 g / m ² .

The sheet thus obtained was cut into a size of 200 mm × 200 mm, and dried at a temperature of 105 ° C. for 1 hour. Four sheets of dried sheets were laminated, and the laminate was used as a core material and inserted into a gas barrier film envelope made of a four-layer structure of nylon, aluminum vapor-deposited PET, aluminum foil, and high-density polyethylene. Getters Co., Ltd. product: C0MB0) was inserted into one envelope. Thereafter, vacuum suction was performed in a vacuum suction device so that the internal pressure was 0.01 Torr and sealed by thermal fusion. The vacuum insulator obtained was 200 mm x 200 mm in size and 10 mm thick. The density of the core material of the obtained vacuum heat insulating material was 220 kg / m <^3> .

<Examples C2 to C3>

A vacuum insulator was obtained in the same manner as in Example C1 except that the type and the use ratio of the fibers used for the core were changed as described in Table 3.

<Reference Example C1>

Vacuum insulation was obtained by the method similar to Example C1 except having used the fiber of Table 3 processed into the sheet form only by the needle punching method according to the following method. In detail, the polyester fiber A was processed into the web shape by the needle punching method. The mass per sheet unit area immediately after processing was 550 g / m ² .

<Reference Example C2>

Except having used the fiber of Table 3, it tried to obtain the vacuum heat insulating material by the method similar to Example C1, but the fiber aggregate melted in amorphous form and the sheet was not obtained.

<Comparative Example C1>

A vacuum insulator was obtained in the same manner as in Example C1, except that 88 g of cotton fibers were used as a core material without processing the fibers shown in Table 3 in a sheet form.

Initial Insulation

Initial heat insulation was evaluated by the same method as the initial heat insulation in Experimental example A. FIG.

<Workability>

The workability at the time of inserting the core material (fiber aggregate) into an outer cover material was evaluated according to the following criteria.

◎; Core material can be easily inserted into the envelope;

○; Workability slightly inferior to ◎, but the core can be easily inserted into the envelope;

×; The core material is soft and the fiber aggregate cannot be evenly inserted into the envelope.

Experimental Example D

<Example D1>

As the core material, a polyester fiber (polyethylene terephthalate fiber) having a fiber thickness of 1.5 denier, an average fiber diameter of 12 µm, and a fiber length of 51 mm was used. The polyester fiber was processed into a sheet by needle punching. The weight per sheet unit area immediately after processing was 660 g / m ² . The sheet was cut to a size of 200 mm x 200 mm. Furthermore, the fiber part about 100 mm x 100 mm part of the said sheet center part was cut out, and the through-hole of the said size was provided. The sheet having the through hole was dried at a temperature of 110 ° C. for 1 hour. The sheet was inserted into a gas barrier film envelope made of a four-layer structure of nylon, aluminum vapor-deposited PET, aluminum foil, and high density polyethylene. Thereafter, vacuum suction was performed in the vacuum suction device so that the internal pressure was 0.01 Torr, and the micro-sealed portion, that is, the bag opening portion, of the peripheral portion of the outer covering material was sealed by heat fusion. The vacuum suction time is 180 seconds. The vacuum insulator obtained was 200 mm x 200 mm in size and 3 mm in thickness. In addition, by sealing the through-hole portion of 100 mm x 100 mm by hot press, the outer surface of the outer packaging material was sealed. Then, the range of center 70mm x 70mm was cut out about the through-hole part. Therefore, the vacuum heat insulating material in which the seal part of 15 mm width was formed along the inner peripheral part of the through-hole part was obtained. The vacuum insulator was excellent in the adhesion between the core material and the outer cover material without the breakage of the outer cover material in the inner circumferential portion of the through hole while having the through hole. The core material density after vacuum suction was 220 kg / m <^3> .

Example D2

As the core material, the same polyester fiber as in Example D1 was used. The polyester fiber was processed into a sheet by needle punching. The weight per sheet unit area immediately after processing was 660 g / m ² . The sheet was cut to a size of 200 mm x 200 mm. Furthermore, the fiber part with respect to the 100 mm x 100 mm part of the said sheet edge part was cut out, and the notch of the said size was provided. The sheet | seat which had the notch was dried at the temperature of 110 degreeC for 1 hour. The sheet was inserted into a gas barrier film envelope made of a four-layer structure of nylon, aluminum vapor-deposited PET, aluminum foil, and high density polyethylene. Thereafter, vacuum suction was performed in the vacuum suction device so that the internal pressure was 0.01 Torr, and the micro-sealed portion, that is, the bag opening portion, of the peripheral portion of the outer covering material was sealed by heat fusion. The vacuum suction time is 180 seconds. The vacuum insulator obtained was 200 mm x 200 mm in size and 3 mm in thickness. Moreover, the outer surface back surfaces were sealed by fusion | melting the notch part of 100 mm x 100 mm by heat press. Then, the range of 60 mm x 60 mm was cut out about the notch part. Therefore, the vacuum heat insulating material in which the 20 mm wide sealing part was formed along the inner peripheral part of a notch was obtained. The said vacuum heat insulating material had a notch, and was excellent in the adhesiveness of a core material and an outer cover material without the breakage and the damage of the outer cover material in an inner peripheral part. The core material density after vacuum suction was 220 kg / m <^3> .

Example D3

As the core material, the same polyester fiber as in Example D1 was used. The polyester fiber was processed into a sheet by needle punching. The weight per sheet unit area immediately after processing was 660 g / m ² . The sheet was cut to a size of 90 mm x 90 mm. Four sheets were dried at a temperature of 110 ° C. for 1 hour. The sheet was inserted into a gas barrier film envelope made of four layers of nylon, aluminum vapor-deposited PET, aluminum foil, and high density polyethylene. The insertion position was inserted so that each core material had a space | interval of 20 mm, so that it might become 200 mm x 200 mm as a whole 4 sheets. Thereafter, vacuum suction was performed in the vacuum suction device so that the internal pressure was 0.01 Torr, and the micro-sealed portion, that is, the bag opening portion, of the peripheral portion of the outer covering material was sealed by heat fusion. The vacuum suction time is 180 seconds. The resulting vacuum insulator was 200 mm x 200 mm in size and 3 mm thick. In addition, the outer surface of the outer packaging material was sealed by fusion by heat press along the outer circumference of each core material having a thickness of 20 mm x 20 mm. The said vacuum insulator had four core materials in an outer cover material, and was excellent in the adhesiveness of a core material and an outer cover material without the damage of the outer cover material in each outer peripheral part of said core material. The core material density after vacuum suction was 220 kg / m <^3> .

Experimental Example E

<Example E1>

The vacuum heat insulating material shown to FIG. 2 (A) and (B) was manufactured with the following method. It demonstrates using FIG.

As the core material 1, a polyester fiber (polyethylene terephthalate fiber) having a fiber thickness of 1.5 denier, an average fiber diameter of 12 µm, and a fiber length of 51 mm was used. The polyester fiber was processed into a sheet by needle punching. The weight per sheet unit area immediately after processing was 660 g / m ² . The sheet was cut to a size of 200 mm x 200 mm. As shown in Fig. 3 (A), the fiber part with respect to the 100 mm x 100 mm part of the said sheet center part was cut out, and the through-hole 5 of the said size was provided. The sheet 1 having the through hole 5 was dried at a temperature of 110 ° C. for 1 hour. The sheet was inserted together with a gas adsorption material (not shown) into a gas barrier film envelope 2 having a four-layer structure of nylon, aluminum vapor-deposited PET, aluminum foil, and high density polyethylene. On the other hand, melting | fusing point of the high density polyethylene which is a sealing layer was 120 degreeC. Thereafter, vacuum suction was performed in the vacuum suction apparatus so that the internal pressure was 0.01 Torr, and the seal portion, that is, the bag opening portion, of the peripheral portion of the outer cover material was sealed by heat welding by pressure welding using a heating member (of the seal portion 3D). formation). The schematic state diagram of the vacuum heat insulating material at this time is FIG. 3 (B). On the other hand, the thickness after vacuum suction is 3 mm, and the vacuum suction time is 180 seconds. Subsequently, the thing after this vacuum suction was heat-processed for 30 second in the 160 degreeC heating oven, and the outer surface of the outer cover material of the sheet through-hole part shown by "6" in FIG. 3 (B) was fused. After cooling, the range (3F in FIG. 2) of the center 70 mm x 70 mm was cut out with respect to the through-hole part. Therefore, the vacuum heat insulating material in which the sealing part (3E in FIG. 2) of 15 mm width was formed along the inner peripheral part of the vacuum heat insulating material side of a through hole part was obtained. The core material density after vacuum suction was 220 kg / m <^3> .

The manufacturing method of the above vacuum heat insulating material does not perform the heat press process which press-contacts the back surface of the outer cover material (6 in FIG. 3 (B)) with a heating member after vacuum exhaust, and is very excellent in productivity. .

<Example E2>

The vacuum heat insulating material shown to FIG. 4 (A) and (B) was manufactured with the following method. It demonstrates using FIG.

As the core material 11, the same polyester fiber as Example E1 was used. The polyester fiber was processed into a sheet by needle punching. The weight per sheet unit area immediately after the processing was 550 g / m ² . The sheet was cut to a size of 200 mm x 200 mm. 5 (A), the fiber part with respect to the 100 mm x 100 mm part of the said sheet edge part was cut out, and the notch 15 of the said size was provided. The sheet 11 having the cutout 15 was dried at a temperature of 110 ° C. for 1 hour. The sheet was inserted together with a gas adsorption material (not shown) into a gas barrier film envelope 12 having a four-layer structure of nylon, aluminum vapor-deposited PET, aluminum foil, and high density polyethylene. On the other hand, melting | fusing point of the high density polyethylene which is a sealing layer was 120 degreeC. Thereafter, vacuum suction was performed in the vacuum suction device so that the internal pressure was 0.01 Torr, and the seal portion, ie, the bag opening portion, at the periphery of the outer packaging material was sealed by heat welding by pressure welding using a heating member (of the seal portion 13D). formation). The schematic state diagram of the vacuum heat insulating material at this time is FIG. 5 (B). On the other hand, the thickness after vacuum suction is 2.5 mm, and the vacuum suction time is 180 seconds. Subsequently, the thing after this vacuum suction was heat-processed for 30 second in the 160 degreeC heating oven, and the outer surface of the outer cover material of the sheet notch part shown by "16" in FIG. 5 (B) was fused. After cooling, the cutout portion was cut out in a range of 60 mm x 60 mm (an oblique line region in FIG. 4). Therefore, the vacuum heat insulating material in which the 20 mm width sealing part (13E in FIG. 4) was formed along the vacuum heat insulating material side inner peripheral part of a notch part was obtained. The core material density after vacuum suction was 220 kg / m <^3> .

The manufacturing method of the above vacuum heat insulating material does not perform the heat press process which press-contacts the back surface of the outer cover material (16 in FIG. 5 (B)) with a heating member after vacuum exhaust, and is very excellent in productivity.

Example E3

The vacuum heat insulating material shown to FIG. 6 (A) and (B) was manufactured with the following method. It demonstrates using FIG.

As the core material 21, polyester fibers similar to those of Example E1 were used. The polyester fiber was processed into a sheet by needle punching. The weight per sheet unit area immediately after processing was 660 g / m ² . The sheet was cut to a size of 90 mm x 90 mm. Four sheets were dried at a temperature of 120 ° C. and a vacuum of 0.1 Torr for 1 hour. As shown in FIG. 7 (A), the sheet 21 was inserted into a gas barrier film envelope 22 having a four-layer structure of nylon, aluminum vapor-deposited PET, aluminum foil, and high density polyethylene. On the other hand, melting | fusing point of the high density polyethylene which is a sealing layer was 120 degreeC. The insertion position was such that each of the cores had a space of 20 mm, so that the entire four sheets were 200 mm x 200 mm. Thereafter, vacuum suction was performed in the vacuum suction device so that the internal pressure was 0.01 Torr, and the seal portion, i.e., the bag opening portion, of the periphery of the outer packaging material was sealed by heat welding by pressure welding using a heating member (of the seal portion 23D). formation). The schematic state diagram of the vacuum heat insulating material at this time is FIG. 7 (B). On the other hand, the thickness after vacuum suction is 3 mm, and the vacuum suction time is 180 seconds. Subsequently, this vacuum suction is heat-treated for 30 seconds in a 160 degreeC heating oven, the outer surface of the outer material outer peripheral part shown by "26" in FIG. 7 (B) is fused, and the vacuum heat insulating material which has multiple core materials is fused. Obtained. The core material density after vacuum suction was 220 kg / m <^3> .

The manufacturing method of the above vacuum heat insulating material is very excellent in productivity since it does not perform the heat press process of pressure-contacting the outer surface back surfaces of the core material outer peripheral part (26 in FIG. 7 (B)) with a heating member after vacuum evacuation.

<Comparative Example E1>

Instead of performing heat treatment in a heating oven after sealing the bag opening portion while maintaining the reduced pressure, a vacuum insulator was produced in the same manner as in Example E1 except that the bag opening portion was sealed while maintaining the reduced pressure after the heat treatment in the heating oven. did. In Fig. 3B, since the fusion between the back surface of the outer covering material of the sheet through-hole portion indicated by "6" is not achieved, by the formation of the through-hole 3F, the decompression state inside the vacuum insulator can be maintained. It is gone.

Experimental Example F

<Example F1>

Breathable PET nonwoven fabric (melting point of PET fiber: 260 ° C) is cut into squares (250 mm x 270 mm: also includes a seal), superimposed two nonwoven fabrics, and the three sides are joined by heat fusion to form a breathable bag Produced the nesting material.

Into the bag-shaped inclusion material, 88 g of a cotton core material made of PET fiber (1.5 denier, melting point of 260 ° C) was uniformly inserted. The opening part was sealed by heat welding, pressing the inner material which accommodated the core material at the heating temperature of 40 degreeC. The core thickness at the time of press was 10 mm. The convex part of height 5mm was formed in the upper mold | type of a press, and the press for the gas adsorption material was formed.

The inner material containing the core and the opening was sealed at 60 ° C. for 60 minutes, and then covered with a gas barrier film made of a four-layer structure made of nylon, aluminum-deposited PET, aluminum foil, and high-density polyethylene (250 mm × 270 mm: seal part view). In addition, one gas adsorption material (SOS GETTERS Co., Ltd. product: COMBO-3) was inserted on the inner cover material in the outer cover material. It was immediately put into the vacuum suction apparatus in that state, and it exhausted under reduced pressure so that internal pressure might be set to 0.01 Torr, and it sealed by heat welding. In the obtained vacuum heat insulating material, the core part was 200 mm x 200 mm in size, and was 10 mm in thickness. The density of the core material of the obtained vacuum heat insulating material was 220 kg / m <^3> .

<Example F2>

Into the same bag-like inclusion material as in Example F1, 88 g of a sheet-shaped core material made of a web obtained by knitting cotton wool fibers used in Example F1 was inserted. The opening part was sealed by heat welding, pressing the inner material which accommodated the core material at the heating temperature of 40 degreeC. The core thickness at the time of press was 10 mm.

The inner material containing the core and the opening was sealed in a gas barrier film envelope (250 mm x 270 mm) formed of a four-layer structure of nylon, aluminum vapor-deposited PET, aluminum foil, and high-density polyethylene. Drying was performed for a minute. After drying, one gas adsorption material (COMBO-3, manufactured by SAS GETTERZ Co., Ltd.) was inserted on the inner cover material in the outer cover material. It was immediately put into the vacuum suction apparatus in that state, and it exhausted under reduced pressure so that internal pressure might be set to 0.01 Torr, and it sealed by heat welding. In the obtained vacuum heat insulating material, the core part was 200 mm x 200 mm in size, and was 10 mm in thickness. The density of the core material of the obtained vacuum heat insulating material was 220 kg / m <^3> .

<Example F3>

PET fibers (melting point 260 ° C.) having a fiber thickness of 1.5 deniers and an average fiber diameter of 11 μm were processed into a sheet by needle punching. The weight per sheet area was 550 g / m ² . The sheet thickness was 10 mm. The sheet was cut to a size of 200 mm x 200 mm to obtain a core material.

The obtained core material was inserted into the bag-like inner packing material like Example F1. The opening part of the inner material which accommodated the core material was sealed by heat welding.

In the state which accommodated the core material and sealed the opening part in the gas barrier film outer cover material (250mm x 270mm: including a seal part) which consists of a 4-layered structure of nylon, aluminum vapor-deposited PET, aluminum foil, and high density polyethylene, It dried for 60 minutes at 120 degreeC. After drying, one gas adsorption material (COMBO-3, manufactured by SAS GETTERZ Co., Ltd.) was inserted on the inner cover material in the outer cover material. It was immediately put into the vacuum suction apparatus in that state, and it exhausted under reduced pressure so that internal pressure might be set to 0.01 Torr, and it sealed by heat welding. In the obtained vacuum heat insulating material, the core part was 200 mm x 200 mm in size, and was 10 mm in thickness. The density of the core material of the obtained vacuum heat insulating material was 220 kg / m <^3> .

<Example F4>

A vacuum insulator was obtained in the same manner as in Example F1, except that 176 g of a cotton core material was uniformly inserted in the bag-shaped inner packing material and the core material thickness at the time of pressing was 20 mm. The thickness of the vacuum insulator was about 20 mm and the core density was 220 kg / m ³ .

<Example F5>

A vacuum insulator was obtained in the same manner as in Example F2, except that 264 g of sheet-shaped core material consisting of three webs was inserted into the bag-shaped inclusion material and the core material thickness at the time of pressing was 30 mm. The thickness of the vacuum insulator was about 30 mm and the core density was 220 kg / m ³ .

<Example F6>

A vacuum insulating material was obtained in the same manner as in Example F3, except that three sheets of the core material obtained in Example F3 were used as the core material. The thickness of the vacuum insulator was about 30 mm and the core density was 220 kg / m ³ .

<Comparative Example F1>

A vacuum insulator was obtained in the same manner as in Example F1, except that the cotton-like PET fiber core was dried at 120 ° C. for 60 minutes and then directly inserted into an outer cover material (250 mm × 270 mm: also including a seal portion). Core density was 220 kg / m ³ .

Initial Insulation

Initial heat insulation was evaluated by the same method as the initial heat insulation in Experimental example A. FIG.

<Long term insulation>

Long-term heat insulation was evaluated by the same method as long-term heat insulation in Experimental example A. FIG.

<Workability>

The workability at the time of inserting a core material or the containing material which accommodated the said core material to an outer material was evaluated according to the following criteria.

○; Easy insertion into envelopes;

×; Insertion into envelopes is cumbersome.

<Production efficiency>

In each Example or comparative example, the manufacturing procedure of a vacuum heat insulating material was repeated 50 times. Of 50 obtained vacuum heat insulating materials, evaluation was made according to the number (x) of the thing which could not hold a vacuum after 1 day after manufacture.

○; 0 to 1;

×; 2 or more.

Experimental Example G

Example G1

As the gas adsorption material, two PET nonwoven fabrics having a weight of 60 g / m ² per unit area made of polyethylene terephthalate fiber were stacked to seal three sides, and a gas adsorption material was put thereinto, and the remaining openings were used. In addition, polyester fibers (polyethylene terephthalate fibers) having a fiber thickness of 1.5 denier, an average fiber diameter of 12 µm, and a fiber length of 51 mm were used as the core material. The polyester fiber was processed into a sheet by needle punching. The weight per sheet unit area immediately after the processing was 550 g / m ² . The sheet was cut into a size of 200 mm × 200 mm, and dried for 1 hour at a temperature of 120 ° C. and a vacuum degree of 0.1 Torr. Four sheets after drying were laminated | stacked, and the said laminated | stacked thing was inserted into the gas barrier film outer cover material which consists of a four layer structure of nylon, aluminum vapor-deposited PET, aluminum foil, and a high density polyethylene. In addition, the said gas adsorption material was mounted on the core material, and it inserted into the outer cover material simultaneously with the core material. Thereafter, vacuum suction was performed in a vacuum suction device so that the internal pressure was 0.01 Torr and sealed by thermal fusion. The vacuum suction time is 180 seconds. The obtained vacuum heat insulating material was 200 mm x 200 mm in size, and was 10 mm in thickness. The density of the core material of the obtained vacuum heat insulating material was 220 kg / m <^3> .

Example G2

A vacuum insulator was prepared in the same manner as in Example G1 except that the gas adsorption material was used by including a chemical adsorption material in a sheet-shaped package made of a nonwoven fabric made of polyester fiber (polyethylene terephthalate fiber) having a weight of 250 g / m ² per unit area. Created. On the other hand, the vacuum suction time is 250 seconds. The core material density after vacuum suction was 220 kg / m <^3> .

<Evaluation>

Since the vacuum heat insulating material of Example G1 is contained in the sheet-shaped package which has a polyester nonwoven fabric even if a gas adsorption material is in an outer cover material, an adsorption material and a core material can be easily separated after use. Moreover, even when the vacuum heat insulating material was curved, there was no problem in the surface state. In addition, since the adsorbent was merely placed on the core material, the productivity was also excellent. The vacuum heat insulating material of Example G2 showed the same effect as Example G1.

Vacuum insulators of the first, second, and third inventions are used as insulation materials for refrigerators, vending machines, cold storage boxes, cold storage cars, storage tanks, storage tanks, hot water tanks, vacuum insulation pipes, molded ceilings of automobiles, bathtubs, and the like. It is applicable and enables a wider range of uses.

In particular, the vacuum insulator of the second invention is applicable to a member having projections such as wiring and piping, for example, a cylindrical tank in a water supply device, a cylindrical pipe in a plumbing facility, and the like, and a housing of a refrigerator. It is also applicable as a heat insulating material which conforms to the uneven part, wiring, and piping, such as the housing of a cold storage box.

Claims (22)

At least a core material and an outer cover material for accommodating the core material to maintain the inside in a reduced pressure state, wherein the core material is a sheet-like fiber aggregate containing 50% by weight or more of polyester fibers having a fiber thickness of 1 to 6 denier Vacuum insulator, characterized in that. The method of claim 1, Vacuum insulation, wherein the polyester fibers are polyethylene terephthalate fibers. The method of claim 1, A vacuum insulator having an average fiber diameter of polyester fibers of 9 to 25 µm. The method of claim 1, A vacuum insulator, in which a fiber assembly is processed into a sheet by a needle punching method. The method of claim 1, Vacuum insulation with a core density of 100 to 450 kg / m ³ . The method of claim 1, A vacuum insulator in which the core is a fiber assembly made of polyester fibers. The method of claim 1, The vacuum heat insulating material whose thickness after vacuum suction of a core material is 0.1-5 mm. The method of claim 7, wherein A vacuum insulator formed by additionally storing a gas adsorbent containing a gas adsorbent material in a soft bag. The method of claim 8, A vacuum insulator, wherein the gas adsorbent bag is made of polyester fiber nonwoven fabric. The method of claim 8, A vacuum insulator, wherein the gas adsorbent bag is made of polyethylene terephthalate fiber nonwoven fabric. The method according to claim 9 or 10, A vacuum insulator, characterized in that the weight per unit area of the nonwoven fabric is 30 to 200 g / m ² . The method of claim 1, A vacuum insulator, wherein the core is a sheet-like fiber assembly comprising at least two kinds of polyester fibers having different melting points. The method of claim 12, A vacuum insulator, in which a fiber assembly is processed into a sheet by a thermal bonding method. The method of claim 12, A vacuum insulator, wherein the fiber aggregate is processed into a sheet by needle punching, and then processed into a sheet by thermal bonding. The method of claim 12, A low-melting-point polyester fiber has a low melting point of 110 to 170 ° C, and the high-melting point polyester fiber has a high melting point of at least 20 ° C higher than that of the low-melting polyester fiber. The method of claim 15, The low melting polyester fiber has a core / shell type structure, the shell part is made of the low melting point polyethylene terephthalate, and the high melting point polyester fiber is made of only the high melting point polyethylene terephthalate. . The method of claim 15, A vacuum insulator, wherein the blending ratio of the low melting polyester fiber and the high melting polyester fiber is 10:90 to 30:70 by weight. The method of claim 1, A vacuum insulator having a seal portion formed by fusion of the outer surface of the outer cover material on a peripheral portion of the outer cover material and an inner region of the peripheral portion. The method of claim 18, The vacuum insulator includes a through hole and / or a cutout, and a back surface of the wrapper is sealed along the inner periphery of the outer cover and the inner circumference of the through hole and / or the cutout. The method of claim 18, Two or more core materials are accommodated in the said outer cover material, and the back surface of the outer wrap material is sealed along the outer periphery of the outer wrapper and each core material. The method of claim 1, Vacuum insulation made by accommodating the inner material containing the core material in the outer material in a reduced pressure state. The method of claim 21, A vacuum insulator, wherein the inclusion material is an inclusion material made of polyethylene terephthalate.

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