JP2002201729A - Thermal insulating material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermal insulating material capable of ensuring strength as well as the excellence in heat insulation property, obtaining the excellent heat insulation property at low cost and controlling the heat insulation property. SOLUTION: A plurality of heat insulating molding bodies 12 and a plurality of heat conductive surface radiation shielding bodies 11 are alternately laminated, a plurality of through-holes 13 are formed in the heat conductive surface radiation shielding bodies 11 and, at the same time, the through-holes filled with binders to connect the adjoining heat insulating molding bodies 12 to each other through the heat conductive surface radiation shielding bodies 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat insulating material.

[0002]

2. Description of the Related Art Conventionally, glass wool,
Inorganic fibers such as mineral wool or ceramic fiber such as rock wool, or fibrous materials such as organic fibers such as wood fibers and cellulose fibers, inorganic foams such as foam glass having independent cells formed therein, or foamed plastics There are known foam-based materials such as organic foams and powder particle-based materials such as powder particles such as ceramics. Among these heat insulating materials, the fibrous material is used by molding into a sheet such as a cotton-like sheet or a felt-like sheet,
The foamed material and the powder particle-based material are used, for example, in the form of a sheet or a molded block.

[0003] These heat insulating materials are used, for example, to insulate and insulate a high-temperature structure used at a high temperature such as a drying furnace or a baking furnace, or to insulate a low-temperature structure used at a low temperature such as a cold storage container. And placing these insulations outside the walls defining the structure, i.e., between the structure and its surrounding atmosphere, to thermally isolate the structure from its surrounding atmosphere. Adiabatic heat retention is performed by.

In general, the thermal conductivity of these insulating materials increases as the bulk density thereof increases, that is, as the porosity decreases, and as the temperature of the insulating material increases,
It is known that the heat insulating property is reduced. Therefore, a low thermal conductivity is required for the heat insulating material. The thermal conductivity of a heat insulating material depends on the density, porosity, bulk density, pore shape, etc. of the constituent materials. The larger the porosity and the lower the bulk density, the more the independent fine porous structure The better the insulation, the better. Further, since the thermal conductivity of the gas is extremely small as compared with that of the solid, the gas is sealed in the pores of the heat insulating material, and particularly excellent heat insulating properties can be obtained when the gas is difficult to move.

[0005]

As described above, the thermal conductivity of the heat insulating material is such that the material constituting the heat insulating material has a large porosity and a low bulk density, and has a large number of independent fine porous structures. The higher the porosity and the lower the bulk density, the lower the strength of the heat insulating material. If the strength is low, it is difficult to maintain its form, and it may be damaged or difficult to handle, resulting in a decrease in workability or workability.

For this reason, for example, Japanese Patent Application Laid-Open No. 8-109700
In the publication, as shown in FIG. 7, a heat insulating wall 60 is formed of a foamed resin plate 62, and a ventilation groove 63 is formed in the foamed resin plate 62 to prevent dew condensation.
And a heat insulating material in which the strength of the foamed resin plate 62 is reinforced by the lath net 61 is described. However, although the heat insulating material can secure the strength, the heat conductivity of the lath net 61 is high, and the heat insulating property of the heat insulating material may be reduced.

In order to realize a heat insulating material having a large porosity, a low bulk density, and a large number of fine porous structures using a single solid material, an expensive low thermal conductivity material such as carbon fiber is required. Must be used, which would increase the cost of the product.

Further, in high-temperature structures such as high-temperature furnaces, since high heat retention is required, a heat insulating material having a high heat insulating property having a low heat conductivity and a large heat capacity is used. However, when a high-temperature structure is kept warm using such a heat insulating material having high heat-insulating properties, a high heat-retention property can be obtained at the time of keeping the temperature, but it takes a long time to lower the temperature of the high-temperature structure. For example, it is necessary to lower the temperature of the heat insulating material and the furnace itself during loading and unloading of the processing object when performing heat treatment on the processing object using a high-temperature furnace, or during maintenance and maintenance of the furnace itself. There was a problem that required.

Accordingly, the present invention has been made to solve the above-mentioned problems, and has a heat insulating material which is excellent in heat insulating property and can secure strength, a heat insulating material which can obtain excellent heat insulating property at low cost, and It is an object of the present invention to provide a heat insulating material capable of controlling heat insulating properties.

[0010]

In order to solve the above-mentioned problems, the present invention according to the first aspect of the present invention is directed to a method of alternately disposing a plurality of heat-insulating molded bodies and a plurality of heat-conductive planar radiation shields. And a plurality of through holes are formed in the heat conductive planar radiation shield, and a binder is filled in these through holes, and the adjacent heat-insulating molded bodies are interposed via the heat conductive planar radiation shield. Are combined.

According to the above construction, the strength is reinforced by the heat conductive planar radiation shield while maintaining the porous structure, large porosity and low bulk density inherent in the heat-insulating molded body, and high strength is secured. Is done. Further, the heat radiation from the inside of the heat insulating material to the outside is shielded by the heat conductive sheet radiation shield, and the heat is diffused in the heat insulating material by the heat conductive sheet radiation shield into the stacking direction and the stack plane. In addition, heat is uniformly distributed inside the heat insulating material without local uneven distribution, thereby lowering thermal conductivity. Further, since the heat inside the heat insulating material is made uniform as described above, even if the temperature inside the heat insulating material is locally increased, it is alleviated that the heat conductivity is thereby increased.

[0012] Therefore, while being excellent in heat insulation, strength can be secured, and workability and workability are excellent.
According to a second aspect of the present invention, in the above configuration, the heat conductive planar radiation shields are arranged at a closer lamination interval on the front surface side than at a lamination interval at a central portion.

[0013] According to the above configuration, since the layers are arranged closer to each other at the front side than at the center, the strength at the front side, which is required to be higher than that at the center in the stacking direction, is ensured. Can be. In addition, by disposing the heat conductive planar radiation shields at closer intervals on the front side, heat diffusion is promoted in the lamination plane on the front side in contact with the structure to be kept warm, and the heat inside the heat insulating material is further reduced. It can be made uniform and the heat insulation can be further improved.

According to a third aspect of the present invention, the heat-insulating molded body is covered with an outer packaging material formed of the same material and having a higher binder content than the heat-insulating molded body. .

According to the above construction, the heat-insulating molded body is covered with the outer wrapping material formed of the same material and having a higher binder content than the heat-insulating molded body. Without impairing the heat insulating properties due to the porous structure, large porosity, and low bulk density, the outer wrapping material enhances the strength and improves workability and workability. In addition, since the outer packaging material is formed from the same material as the heat-insulating molded body, recycling is easy.

According to a fourth aspect of the present invention, a reinforcing sheet formed of the same material and having a higher binder content than the heat-insulating molded body is inserted between the plurality of heat-insulating molded bodies. Things.

According to the above construction, a reinforcing sheet made of the same material and having a higher binder content than the heat insulating molded body is inserted between the plurality of heat insulating molded bodies. Thereby, the heat-insulating molded body is reinforced without impairing the heat-insulating properties due to the inherent porous structure, large porosity, low bulk density, etc., thereby improving the strength, and is excellent in workability and workability. In addition, since the reinforcing sheet is formed from the same material as the heat-insulating molded body, recycling is easy.

According to a fifth aspect of the present invention, an inclined space inclined at a predetermined angle with respect to the thickness direction is formed in the heat-insulating molded body. According to the configuration, since the inclined gap is formed inside the heat-insulating molded body, a heat transfer path longer than the thickness of the heat-insulating material is pseudo-formed, and the heat conductivity in the heat-insulating material is reduced. Furthermore, since the heat convection phenomenon occurs in the inclined gap, the heat that has moved from the high-temperature side to the low-temperature side is further moved from the low-temperature side to the high-temperature side by a kind of heat pipe effect, and the thermal conductivity further decreases. . According to this, a heat insulating material having low thermal conductivity can be obtained at low cost without using an expensive low thermal conductivity material such as carbon fiber.

Further, the invention according to claim 6 is characterized in that the heat-insulating molded body is covered with an outer packaging material having gas sealing properties, and pressure adjusting means for adjusting the pressure in the outer packaging material is provided. is there.

According to the above configuration, since the pressure adjusting means is provided, the internal pressure in the outer package material, that is, the internal pressure of the heat insulating material can be adjusted to control the heat insulating property of the heat insulating material. That is, when the structure to be kept warm is kept warm, the inside of the heat insulating material is depressurized by the pressure adjusting means to lower the heat conductivity, thereby improving the heat insulating property. When you stop
A gas is supplied into the heat insulating material by the pressure adjusting means to increase the thermal conductivity, thereby lowering the heat insulating property, and the temperature of the heat insulating material and thus the structure to be kept warm can be reduced in a short time.

Therefore, high heat insulation is exhibited when the structure to be kept warm is kept warm. In addition, when the heat retention is stopped, the temperature can be lowered in a short time, and the switching of operations such as taking in and out of a processing object to be processed in the structure and maintenance of the structure can be performed efficiently.

Further, according to a seventh aspect of the present invention, the heat-insulating molded body is formed from a fiber material, a foam material, or a powder particle material. According to the configuration, since the heat-insulating molded body is formed from the fiber-based material, the foamed-particle-based material, or the powder-particle-based material, a porous structure, a large porosity, and a small bulk density can be easily secured.

Hereinafter, the present invention will be described in detail. Claim 1
In the invention described in the above, as the heat conductive planar radiation shield laminated between a plurality of heat-insulating molded bodies, those having a high thermal conductivity and a material having a high thermal radiation shield are preferable, and in particular, It is desirable to use a metal material having high tensile strength at high temperatures and small distortion and deformation due to heat. Examples of such a metal material include SU
A stainless steel foil such as S316L or a titanium foil is preferable. When the heat insulating material is used at a relatively low temperature, for example, at a temperature exposed to 450 ° C. or less, an aluminum foil can be used. Further, a graphite sheet, a mica material or the like can be used.

As the heat insulating material constituting the heat insulating molded body, a known material is used. For example, fiber materials such as inorganic fibers such as ceramic fibers or organic fibers such as wood fibers, foam materials such as shelled foam particles such as glass balloons, and powder particles such as ceramic fine particles. Materials are used.

Further, the shape of the heat-insulating molded body may be any shape such as a sheet shape, a board shape, a block shape and a mat shape. The shape of the through-hole to be filled with the binder to be formed in the heat conductive planar radiation shielding body may be any shape such as a polygon other than a circle, but the ease of the perforation and the isodirectionality of the heat insulating material are ensured. In addition, in order to secure the peel strength between the heat-insulating molded bodies constituting the heat-insulating material, a circular shape is preferable. Depending on the number of sides of the polygon, the peel strength of the polygonal through-hole is lower than that of the circular through-hole. , Which may cause peeling.

Further, as described above, since the heat conductive planar radiation shield has the function of diffusing heat in the direction of lamination of the heat insulating material, that is, the thickness direction, the heat insulating material is installed on a vertical wall surface having a temperature distribution. In such a case, when the through hole formed in the heat conductive planar radiation shield is formed in an elliptical shape that is long in a direction perpendicular to the wall surface, heat received by the heat insulating material from the wall surface can be uniform. . On the other hand, when an elliptical through-hole that is long in the horizontal direction with respect to the vertical wall surface is formed in the heat conductive planar radiation shield, it is possible to suppress the heat diffusion in the laminated surface of the heat insulating material.

The through-holes formed in the heat conductive planar radiation shield are preferably arranged in a staggered manner, and between the adjacent heat conductive planar radiation shields from the viewpoint of thermal radiation shielding and peel strength. It is desirable to arrange them so that they do not overlap with each other.

The plane aperture ratio of the through hole, that is, the ratio of the area of the through hole to the area of the heat conductive planar radiation shield is 5% to 40% from the viewpoint of thermal radiation shielding and peel strength.
It is good to do. More preferably, it is 20% or less from the viewpoint of heat radiation shielding and 10% or more from the viewpoint of peel strength. Also, the through-holes need not necessarily be arranged uniformly over the entire surface of the heat conductive planar radiation shield, and the end of the heat conductive planar radiation shield located at the end of the heat insulating material where peel strength tends to decrease. That is, it is also possible to arrange the components in a concentrated manner at the peripheral portion or the like and reduce the number of components arranged at the central portion, thereby securing the peel strength.

Further, the laminating intervals in the laminating direction of the heat conductive planar radiation shields need not be equal, but may be unequal. In particular, the intervals at which the heat conductive planar radiation shields are arranged may be closer to the surface of the heat insulating material, and the intervals may be larger at the center. Thereby, the peel strength on the surface side can be ensured in the same manner as the arrangement of the through holes, and the heat in the high-temperature portion is diffused to the low-temperature portion in the lamination surface, and the heat inside the heat insulating material is made uniform. It is possible to alleviate the properties of the heat insulating material, which increases the thermal conductivity as the temperature increases.

Further, in consideration of the reduction of heat loss due to heat radiation and moisture proofness, it is preferable to dispose a heat conductive planar radiation shield on the surface of the heat insulating material and cover it. When the thermal conductivity of the heat conductive planar radiation shield is different on both surfaces, it is preferable to arrange the surface having a large thermal reflectance on the side of the structure to be kept warm.

The heat insulating material can be manufactured by various methods. For example, when using a fibrous material as a heat insulating material, for example, in the process of forming a fibrous material by a normal papermaking method and forming a heat insulating molded body, a thermally conductive planar radiation shielding body is inserted, and the fibers are bound with a binder. To form a heat-insulating molded body, and filling the through-hole with a binder to bond adjacent heat-insulating molded bodies to each other. When using a foamed particle-based material or a powdered particle-based material as a heat insulating material, for example, a foamed particle-based material or a powdered particle-based material and a heat conductive planar radiation shield are alternately laminated together with a binder in a mold. After that, it can be manufactured by a press working method of compressing the expanded particle material or the powder particle material and curing the binder.

Next, in the invention according to claim 3 or 4, as the heat-insulating molded body, a fibrous material, a foamed particle-based material, a powdered particle-based material, or the like is used as described above by using a binder. Those molded into a board shape, a block shape, a mat shape or the like are used.

As the outer wrapping material or the reinforcing sheet, those formed of the same material as the material constituting the heat-insulating molded body and having a higher binder content than the heat-insulating molded body are used.

In the outer wrapping material or the reinforcing sheet, the contact area between the fibers or between the foamed particles and the like, which is bonded by the binder, is increased as compared with the heat-insulating molded body, and the bonding force therebetween is increased. Shows high strength.

This heat insulating material is easy to recycle because the heat insulating molded body and the outer packaging material or the reinforcing sheet are formed of the same material. Have the same properties such as thermal conductivity, heat resistance, corrosion resistance, and water resistance, so that they can be easily processed and the restrictions on structures to be kept warm are relaxed.

According to the third aspect of the present invention, the heat insulating material can be obtained by further wrapping fibers or foamed particles in an outer wrapping material without using a binder.
In this case, the contact area between the fibers constituting the heat-insulating molded body or the like is reduced, the porosity is increased, and a heat-insulating material having a lower thermal conductivity can be obtained. In this heat insulating material, if the outer packaging material is removed, pure fibers or foamed particles containing no binder and constituting the heat insulating molded body can be recycled. For example, it can be recycled again as a heat-insulating molded article or as an outer packaging material, and can be easily decomposed and separated, and can be recycled as it is without separation.

In the fifth aspect of the present invention, the angle θ of the inclined gap with respect to the thickness direction of the heat-insulating molded body is preferably 30 ° or more in order to develop convection and reduce the thermal conductivity. When the angle θ is from 30 ° to 90 °, a substantially constant thermal conductivity is exhibited. However, when the angle θ is large, processing for forming an inclined gap may be difficult. Considering the ease of
° to 60 ° is desirable. However, if processing is possible,
It can be over 60 °.

The heat-insulating material having the inclined gaps is formed by cutting a heat-insulating molded body formed by, for example, the above-mentioned papermaking method, press working method, injection method, or the like by milling or the like to form inclined gaps. It is obtained by laminating a plurality of formed heat-insulating molded bodies, or by laminating a heat-insulating molded body having an inclined gap formed thereon and an unprocessed heat-insulating molded body. This heat insulating material is particularly effective when installed on a vertical wall surface.

In the invention as set forth in claim 6, the above-mentioned known heat-insulating molded body is used. As the outer packaging material having gas sealing properties, those made of glass, hard plastic, metal, ceramics, or the like are used. When using glass, metal, ceramics, etc.,
A method of applying these slurries to the surface of the heat-insulating molded body to form an outer packaging material can be adopted. Alternatively, glass, hard plastic, metal, ceramics, or the like may be formed into a thin molded body, such as a sheet, to cover the heat-insulating molded body.

As the pressure adjusting means, a vacuum pump for reducing the pressure inside the heat insulating material, a fan for supplying gas into the heat insulating material, and the like are used. It is attached to the heat insulating material via opening / closing means such as a valve.

When a gas is supplied to the inside of the heat insulating material to lower the temperature of a structure such as a high-temperature furnace, a gas at a constant temperature is continuously supplied to the inside of the heat insulating material so that the inside of the heat insulating material is equal to the gas. When the temperature is lowered, the time required for lowering the temperature can be further reduced.

The heat insulating material of the present invention can be used, for example, in a baking furnace used for baking electric parts such as plasma displays and ceramic substrates, as well as a drying furnace, a baking furnace, and a refrigeration vessel used in the steel field, chemical material processing and food industry. It is preferably used for heat insulation for preserving and preserving high-temperature structures such as cooling equipment or containers or low-temperature structures including dwellings, and for heat insulation panels that are effective for sound insulation.

Since the heat insulating material has a porous structure inside, it has characteristics necessary for sound insulation and sound absorption, so that it can be suitably used as a sound insulating material.

[0044]

Next, an embodiment of the present invention will be described with reference to the drawings. Embodiment 1 A heat insulating material according to Embodiment 1 of the present invention will be described with reference to FIGS.

As shown in FIG. 1, a heat insulating material 10 includes a plurality of heat insulating molded bodies 12 and a plurality of heat conductive planar radiation shielding bodies 11.
Consists of The heat-insulating molded body 12 is formed into a sheet by bonding, for example, a fibrous material with a binder, a porous structure is formed between the fibers, and has a large porosity and a low bulk density. On the other hand, the heat conductive planar radiation shield 11 is formed from a metal material such as aluminum foil, and is formed by arranging a plurality of circular through holes 13 in a staggered manner. The through holes 13 are formed so as not to overlap with the adjacent heat-insulating molded bodies 12.

The heat insulating material 10 has a heat insulating molded body 12 and a heat conductive planar radiation shielding body 11 alternately laminated to form a laminated unit 14. As shown in FIG. Are filled with the binder B, and the adjacent heat-insulating molded bodies 12 are connected to each other via the heat-conductive planar radiation shield 11.

According to the heat insulating material 10, since the heat conductive planar radiation shielding body 11 is laminated, the heat insulating molded body 12 retains a large porosity and a low bulk density due to the inherent porous structure. The strength is reinforced by the heat conductive planar radiation shield 11 and has high strength. Further, heat radiation from the inside to the outside of the heat insulating material 10 is shielded by the heat conductive planar radiation shield 11, thereby lowering the thermal conductivity. The heat is diffused in the laminating direction and in the laminating plane, so that the heat is not unevenly distributed in the heat insulating material 10 but is homogenized in the heat insulating material 10, thereby further reducing the thermal conductivity. Further, since the heat inside the heat insulating material 10 is made uniform, even if the temperature inside the heat insulating material 10 is locally increased, it is alleviated that the heat conductivity is thereby increased. Further, the heat conductive planar radiation shield 1
1, the through holes 13 are formed in a staggered manner and formed so as not to overlap between the adjacent heat conductive planar radiation shields 11, and a binder B is filled into the through holes 13 to form a heat insulating molded body 12.
It has high peel strength because of bonding between the layers.

[0048] Therefore, while being excellent in heat insulation, the strength can be ensured, so that the workability and workability are excellent, and the peel strength is excellent. The heat-insulating molded body 12 has a bulk density of 2 in which ceramic fibers made of aluminosilicate are bound by a binder.
Using a 50 kg / m ³ inorganic sheet, the heat conductive planar radiation shield 11 was 15 μm thick and had an aperture ratio of 10 μm.
% Of the aluminum foil on which the through holes 13 are formed, 36 aluminum foils and the heat-insulating molded body 12 are alternately laminated, and a binder B is added to the through holes 13.
And the adjacent inorganic sheets are bonded to each other to have a thickness of 20
A heat insulating material 10 of 0 mm was made.

The thermal conductivity and strength of the heat insulating material 10 were measured, and the results are shown in Table 1. For comparison, a heat insulating material was formed from a 200 mm thick inorganic sheet made of the same ceramic fiber as described above, and its thermal conductivity and strength were measured. The results are shown in Table 1.

As is clear from Table 1, according to the present embodiment, the thermal conductivity of the heat insulating material can be reduced and the strength can be improved.

[0051]

[Table 1] Embodiment 2 A heat insulating material according to Embodiment 2 of the present invention will be described with reference to FIG.

As shown in FIG. 3, the heat insulating material 20 is obtained by covering the entire surface of a heat insulating molded body 21 with an outer packaging material 22. The heat-insulating molded body 21 is formed into a sheet by, for example, binding a foamed particle-based material with a binder, and has a large porosity and a low bulk density due to the voids in the foamed particles and the gaps between the foamed particles. On the other hand, the outer packaging material 22 is formed by forming a foamed particle-based material made of the same material as the heat-insulating molded body 21 into a sheet with a higher binder content than the heat-insulating molded body 21, and forming the sheet as the outer packaging material 22. It is.

According to the heat insulating material 20, since the outer packaging material 22 has a higher binder content than the heat insulating molded body 21, the contact area where the expanded particles are bonded by the binder is large, and the bonding between the particles is large. It has strong power and high strength. Moreover, since the outer packaging material 22 is formed from a sheet made of a foamed particle-based material made of the same material as the sheet constituting the heat insulating molded body 21, recycling is easy.

The heat-insulating molded body 21 has a bulk density of 200 kg / m ³ and a length and width of 192, each of which is formed by bonding glass balloons, which are shelled foam particles, with a binder.
using an inorganic sheet having a thickness of 12 mm and a thickness of 12 mm.
The bulk density of a glass balloon formed with a binder content greater than that of the inorganic sheet is 300 kg /
Using an inorganic sheet having a thickness of m ³ and a thickness of 4 mm, the entire surface of the heat-insulating molded body 21 is covered with an outer wrapping material 22.
It was created.

The thermal conductivity and strength of the heat insulating material 20 were measured, and the results are shown in Table 2. For comparison, a heat insulating material was prepared from an inorganic sheet having a bulk density of 200 kg / m ³ , a length and width of 200 mm, and a thickness of 20 mm each made of a glass balloon, and the thermal conductivity and strength thereof were measured. It was shown to.

As is clear from Table 2, according to the present embodiment, it is possible to improve the strength while keeping the thermal conductivity of the heat insulating material low.

[0057]

[Table 2] Embodiment 3 A heat insulating material according to Embodiment 3 of the present invention will be described with reference to FIG.

As shown in FIG. 4, the heat insulating material 30 has a reinforcing sheet 32 inserted between a plurality of heat insulating molded bodies 31. The heat-insulating molded body 31 is formed into a sheet by bonding, for example, a fibrous material with a binder, a porous structure is formed between the fibers, and has a large porosity and a low bulk density. On the other hand, the reinforcing sheet 32 is made of the heat-insulating molded body 31.
A fibrous material made of the same material as described above is formed into a sheet with a higher binder content than the heat-insulating molded body 31.

According to the heat insulating material 30, the reinforcing sheet 32
Since the content of the binder is larger than that of the heat-insulating molded body 31, the contact area where the fibers are bonded by the binder is large, the bonding force between the fibers is strong, and the strength is high. Moreover, since the reinforcing sheet 32 is formed from a sheet made of a fibrous material made of the same material as the sheet constituting the heat insulating molded body 31, recycling is easy. Embodiment 4 A heat insulating material according to Embodiment 4 of the present invention will be described with reference to FIG.

As shown in FIG. 5, the heat insulating material 40 is formed by laminating a plurality of heat insulating molded bodies 41a and 41b and forming a plurality of inclined voids 43 therein. Each of the heat-insulating molded bodies 41a and 41b is formed into a sheet by binding, for example, a fibrous material with a binder, a porous structure is formed between fibers, and has a large porosity and a low bulk density. Further, a plurality of inclined grooves 42a, 42b inclined at a predetermined angle θ with respect to the thickness direction A are formed on one surface of each of the heat insulating molded bodies 41a, 41b.
These inclined grooves 42 a and 42 b are
In each of a and 41b, a line segment X drawn in the thickness direction of the heat insulating material 40 is formed at a predetermined interval so as to have a positional relationship crossing two adjacent inclined grooves. For example,
In the heat-insulating molded body 41b, the line segment X is
It is formed so as to cross the two inclined grooves 42b, 42b. The two heat-insulating molded bodies 41a and 41b are joined so that the inclined grooves 42a and 42b communicate with each other, and the two are adhered to each other to form a plurality of inclined gaps 43 therein.

According to the heat insulating material 40, since the inclined space 43 is formed inside the heat insulating material 40, a heat transfer path longer than the thickness of the heat insulating material 40 is simulated, and the heat conductivity in the heat insulating material 40 is reduced. I do. Further, in the inclined space 43,
Since a heat convection phenomenon occurs, a kind of heat pipe-like operation occurs. That is, as shown by the arrow S, heat moves from the high temperature side to the low temperature side, and
As shown by, the convection moves from the low temperature side to the high temperature side. Thus, this further reduces the thermal conductivity. Further, in each of the heat-insulating molded bodies 41a and 41b, two adjacent inclined grooves are arranged so as to have a positional relationship across a line X drawn in the thickness direction of the heat insulating material. As a result, the heat is made uniform in the thickness direction of the heat insulating material, and the high temperature on the high temperature side is reduced.

As the heat-insulating molded bodies 41a and 41b,
An inorganic sheet having a bulk density of 250 kg / m ³ , a length and width of 200 mm, and a thickness of 25 mm, respectively, in which ceramic fibers made of aluminosilicate are bound by a binder, and the angle θ of 30 degrees on one surface of the two inorganic sheets The inclined grooves 42a and 42b having an angle of 20 mm, a width of 20 mm, and a cutting depth of 20 mm were provided at intervals of 10 mm. The two inorganic sheets are joined so that the inclined grooves 42a and 42b communicate with each other, and the two are adhered to each other to form a plurality of inclined voids 43 therein.
A heat insulating material 40 having a thickness of 50 mm and a thickness of 50 mm as shown in FIG. 5 was prepared.

The thermal conductivity of the heat insulating material 40 was measured, and the results are shown in Table 3. For comparison, a heat insulating material made of the ceramic sheet made of the ceramic fiber and having a thickness of 50 mm and having no inclined voids, and a heat insulating material similar to that of the above-described embodiment except that the angle θ was set to 0 ° were prepared. The conductivity was measured and the results are shown in Table 3.

As is clear from Table 3, according to the present embodiment, the thermal conductivity of the heat insulating material can be reduced.

[0065]

[Table 3] Embodiment 5 A heat insulating material according to Embodiment 5 of the present invention will be described with reference to FIG.

As shown in FIG. 6, the heat insulating material 50 covers the entire surface of the heat insulating molded body 51 with an outer wrapping material 52 having gas sealing properties, and a vacuum for adjusting the pressure in the heat insulating material 50. A pump 53 is attached.

The heat-insulating molded body 51 is formed into a sheet by bonding, for example, a foamed particle material with a binder, and has a large porosity and a low bulk density due to the voids in the foamed particles. On the other hand, the outer packaging material 52 is formed by laminating a synthetic resin sheet such as a polyacrylonitrile resin and a metal material such as an aluminum foil, and has a gas sealing property.

The heat insulating material 50 is provided with a pipe 54 as a connecting means for mounting a vacuum pump 53, and the vacuum pump 53 is mounted via a valve 55 as an opening / closing means. A pipe 56 and a valve 57 are also provided at another place of 50.

When a structure to be kept warm, such as a high-temperature furnace, is to be kept warm using the heat insulating material 50, the valve 55 is opened with the valve 57 closed, and the air inside the heat insulating material 50 is sucked by the vacuum pump 53. Then, the pressure inside the heat insulating material 50 is reduced to lower the thermal conductivity. Then, in this state, the high-temperature furnace is maintained at a predetermined temperature, and for example, the object to be processed is heat-treated.

When the object to be treated is taken out of the high-temperature furnace, the valve 57 is opened and the vacuum pump 53 is operated to supply air into the heat insulating material 50 and bring the internal pressure to atmospheric pressure. Of the structure to be kept warm together with the heat insulating material 50 to a predetermined temperature in a short time.

According to this, when the high-temperature furnace is kept warm, the heat conductivity of the heat insulating material 50 is reduced to exhibit high heat insulating properties. On the other hand, when the heat keeping is stopped, the heat conductivity of the heat insulating material 50 is increased, and the heat insulating material 50 is eventually lowered. The temperature of the high-temperature furnace itself decreases in a short time via the outer wall of the high-temperature furnace.

The heat-insulating molded body 51 has a bulk density of 200 kg / m ³ and a length and width of 200 kg / m ³ , each of which is formed by bonding glass balloons, which are shelled foam particles, with a binder.
using an inorganic sheet having a thickness of 20 mm and a thickness of 20 mm.
As a polyacrylonitrile resin sheet and a 200 μm-thick laminated sheet obtained by laminating an aluminum foil,
The whole surface of the inorganic sheet was covered with the laminated sheet, and a vacuum pump 53 was attached as shown in FIG.

The vacuum pump 53 is sucked and the heat insulating material 50
Thermal conductivity and internal pressure when the internal pressure is reduced to 6.5 × 10 ² Pa at atmospheric pressure (1037 × 10 ² Pa)
Thermal conductivity when kept at 200 ° C
After heating to room temperature (20 ° C.) after heating, the cooling time until the heat insulating material 50 reached 40 ° C. was measured. The results are shown in Table 4.

As is apparent from Table 4, when the internal pressure of the heat insulating material is reduced, the heat conductivity is reduced, the heat insulating property is improved, and the cooling time is prolonged. On the other hand, when the internal pressure is maintained at the atmospheric pressure, It can be seen that the thermal conductivity is increased, the heat insulation is reduced, and the cooling time is shortened.

[0075]

[Table 4] This heat insulating material is practically used, for example, by controlling so that the thermal conductivity becomes maximum or minimum. Of course, the internal pressure is adjusted to a predetermined pressure between 6.5 × 10 ² Pa and the atmospheric pressure, and the value of the thermal conductivity is controlled to be a predetermined value between the maximum value and the minimum value. Can also.

Further, the internal pressure is set to 6.5 × 10 ² P
Although it is possible to reduce the thermal conductivity by reducing the pressure so as to be even lower than a, the heat-insulating molded body constituting the heat insulating material has a porous structure, and in order to make such a low pressure Since it requires a long time, the internal pressure is usually reduced to 6.5 × 10 ² Pa before use.

In this embodiment, the heat insulating material 50 is used.
In order to set the internal pressure to the atmospheric pressure, a fan or the like may be connected to the valve 57 so that air is sent into the heat insulating material 50.

[0078]

As described above, according to the first aspect of the present invention, excellent heat insulation and strength can be ensured, resulting in excellent workability and workability.

Further, according to the second aspect of the present invention, it is possible to secure the strength on the surface side of the heat insulating material, which requires high strength, and to further improve the heat insulating property.

According to the third aspect of the present invention, the strength can be secured without lowering the heat insulating property.
Excellent workability and workability. Further, according to the invention as set forth in claim 4, strength can be secured without deteriorating heat insulation, and workability and workability are excellent.

According to the fifth aspect of the present invention, a heat insulating material having excellent heat insulating properties can be obtained at low cost. Furthermore, according to the invention described in claim 6, the heat insulating property of the heat insulating material can be controlled. Therefore, when the structure to be kept warm is kept warm, the heat insulation property can be increased to keep the structure warm.In addition, when the structure to be kept warm is stopped, the heat insulation property is reduced to reduce the temperature of the structure to be kept warm. The temperature can be reduced in a short time, and operations such as taking in and out of the object to be treated and maintenance of a structure to be kept warm can be efficiently performed.

Further, according to the invention described in claim 7,
A porous structure, a large porosity, and a small bulk density can be easily secured.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a heat insulating material according to a first embodiment of the present invention.

FIG. 2 is a sectional view of the same.

FIG. 3 is a sectional view showing a heat insulating material according to a second embodiment of the present invention.

FIG. 4 is a sectional view showing a heat insulating material according to a third embodiment of the present invention.

FIG. 5 is a sectional view showing a heat insulating material according to a fourth embodiment of the present invention.

FIG. 6 is a sectional view showing a heat insulating material according to a fifth embodiment of the present invention.

FIG. 7 is a perspective view showing an example of a conventional heat insulating material.

[Explanation of symbols]

10, 20, 30, 40, 50 Insulating material 11 Thermally conductive planar radiation shielding body 12, 21, 31, 41a, 41b, 51 Insulating molded body 13 Through hole 14 Stacking unit 22 Outer packaging material 32 Reinforcement sheet 42a, 42b Inclined groove 43 Inclined gap 52 Outer packaging material 53 Vacuum pump 54, 56 Pipe 55, 57 Valve 60 Insulating wall 61 Lath net 62 Foamed resin plate 63 Vent B Binder S, T Heat transfer direction

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Yuji Tsutsui 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture F-term in Matsushita Electric Industrial Co., Ltd. (reference) 2E001 DD01 FA26 GA12 GA18 GA22 GA24 GA42 HA00 HA34 HB04 HD11 LA04 2E162 CA00 CB14 CB24 CD09 4F100 AB10C AB10D AB33C AB33D BA05 BA07 BA10E BA25 CB00G DC11A DC11B DC11C DC11D DE01A DE01B DG01A DG01B DJ01A DJ01B GB07 GB51 JD02E JD11C JD11D JJ02 JJ02A JJ02B

Claims (7)

[Claims] 1. A plurality of heat-insulating molded bodies and a plurality of heat-conductive surface radiation shields are alternately stacked, and a plurality of through holes are formed in the heat-conductive surface radiation shields. A heat insulating material, characterized in that the through holes are filled with a binder, and adjacent heat insulating molded bodies are connected to each other via a heat conductive planar radiation shielding body. 2. The heat insulating material according to claim 1, wherein said heat conductive planar radiation shields are arranged at a closer lamination interval on the front side than at a lamination interval at a central portion. 3. A heat insulating material characterized in that the heat insulating molded body is covered with an outer wrapping material formed of the same material and having a higher binder content than the heat insulating molded body. 4. A heat insulating material wherein a reinforcing sheet formed of the same material and having a higher binder content than the heat insulating molded body is inserted between a plurality of heat insulating molded bodies. 5. A heat insulating material characterized in that an inclined space inclined at a predetermined angle with respect to a thickness direction is formed inside a heat insulating molded body. 6. A heat insulating material characterized in that the heat insulating molded body is covered with an outer packaging material having a gas sealing property and a pressure adjusting means for adjusting the pressure in the outer packaging material is provided. 7. The heat insulating material according to claim 1, wherein the heat insulating molded body is formed from a fiber material, a foam material, or a powder particle material.