CN109890256B

CN109890256B - Heat-insulating container

Info

Publication number: CN109890256B
Application number: CN201780059170.9A
Authority: CN
Inventors: 佐藤义治; 大泽秀斗
Original assignee: Zojirushi Corp
Current assignee: Zojirushi Corp
Priority date: 2016-09-26
Filing date: 2017-09-11
Publication date: 2020-02-18
Anticipated expiration: 2037-09-11
Also published as: JP6518017B2; CN109890256A; DE112017004804B4; DE112017004804T5; WO2018056095A1; JPWO2018056095A1

Abstract

The invention provides a glass heat-insulating container which is less damaged during manufacturing and has excellent impact strength. The heat-insulating container (1) is provided with: an inner glass container (2); an outer glass container (3) surrounding the outer side of the inner container (2) and connected to the inner container (2) at an opening (1 h); and a spacer (10) disposed between the inner container (2) and the outer container (3), wherein the spacer (10) is made of a calcium silicate-based material or a diatomaceous earth-based material, and the load required for compressing 0.1mm at a compression rate of 0.1 mm/min is 175N or less.

Description

Heat-insulating container

Technical Field

The present invention relates to an insulated container, and more particularly to an insulated container made of glass.

Background

Conventionally, there are heat-insulating containers using glass containers. This heat insulating container is, for example, incorporated in an outer package case, has a structure in which an opening is closed with a lid member, and is used for a product which is intended to maintain the temperature of contents such as hot water at a desired temperature for a long time (for example, patent document 1).

Further, patent document 2 discloses a glass vacuum insulation container in which a space between an inner container and an outer container made of glass is vacuum-exhausted to form a vacuum insulation layer, and a spacer (spacer) is disposed between the inner container and the outer container.

The spacer is of course preferably a material with a low thermal conductivity. In addition, it has been considered that the separator needs to have flexibility and cushioning properties. That is, in the production of the heat insulating container, the spacer needs to have flexibility for securing a space between the inner container and the outer container while preventing the inner container and the outer container from being deformed and damaged by heat. Further, the spacer is required to have cushioning properties for preventing breakage of the container in response to an impact such as dropping of the product by a user during use.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2000-201834

Patent document 2: japanese patent laid-open publication No. 2002-58605

Disclosure of Invention

Problems to be solved by the invention

The present inventors have conducted extensive studies on separators in order to improve the above-described separators. That is, the separator is considered to be required to have flexibility in the production of the heat insulating container, cushioning properties in use, and the like, and a material having a certain degree of flexibility is preferable. Therefore, a calcium silicate material known as a building material has a low thermal conductivity, and thus may be applied to a heat insulating container. However, since calcium silicate-based materials are harder than conventional separators, their application to separators for heat-insulating containers is not considered to be ideal.

However, the present inventors have conducted extensive studies and as a result, have found that a heat insulating container which can prevent breakage during production and has excellent impact strength during use can be obtained by using a calcium silicate-based material or a diatomaceous earth-based material having a specific hardness as a separator, and have completed the present invention.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a glass heat insulating container which is less broken during production and has excellent impact strength.

Means for solving the problems

The above object can be achieved by the following means. Namely, the present invention is as follows.

[ 1 ] an insulated container comprising: an inner container made of glass; an outer container made of glass surrounding the outer side of the inner container and connected to the inner container at an opening portion; and a separator arranged between the inner container and the outer container in contact with the two containers, wherein a space surrounded by the inner container and the outer container is set to be vacuum,

the spacer is made of a calcium silicate material or a diatomaceous earth material, and the load required for compressing 0.1mm at a compression rate of 0.1 mm/min is 175N or less.

[ 2 ] the heat insulating container according to [ 1 ], wherein at least one surface of the separator, which is in contact with the inner container and the outer container, is formed as a concave-convex surface.

[ 3 ] the heat insulating container according to [ 1 ] or [ 2 ], wherein a surface roughness of at least one of surfaces of the separator in contact with the inner container and the outer container is 20 to 50 μm in terms of an arithmetic average height Sa.

The heat-insulating container according to any one of [ 1 ] to [ 3 ], wherein a load required for compressing the separator by 0.5mm at a compression rate of 0.1 mm/min is 1500N or more.

[ 5 ] the heat insulating container according to any one of [ 1 ] to [ 4 ], wherein a material of the separator is a calcium silicate-based material, and the calcium silicate-based material is obtained as follows: dewatering and molding a slurry prepared from a homogeneous mixture of the following (A) to (D), and molding the resulting product at 6kg/cm²Steaming under the above-mentioned pressurized steam to react silicic acid raw material and lime raw material, heating to 330 deg.C or higher under atmospheric pressure to remove water released from the molded article,

(A)CaO/SiO ₂100 parts by weight of a mixture of a lime raw material and a silicic acid raw material in a molar ratio of 0.6 to 1.2

(B) 50-170 parts by weight of xonotlite obtained by hydrothermal synthesis

(C) 15 to 150 parts by weight of fibrous wollastonite

(D) 2-8 times of the total solid content of water.

Effects of the invention

According to the present invention, it is possible to provide a heat insulating container which can suppress breakage of the container during production and has excellent impact strength during use.

Drawings

Fig. 1 is a sectional view of a principal part of a heat insulating container according to an embodiment of the present invention.

Fig. 2 is a perspective view of the spacer shown in fig. 1.

Fig. 3 is a schematic sectional view of a portion along the line a-a shown in fig. 2, (a) is an enlarged sectional view showing a state where the side surface of the container is in contact with the surface of the spacer, and (b) is an enlarged sectional view showing a state where the side surface of the container is crushed by the surface of the spacer.

Fig. 4 is a view showing a measurement region of the surface roughness of the spacer.

Fig. 5 is a view showing a measurement region of the surface roughness of the spacer.

Fig. 6 is a 3D image of the spacer (1) and measurement data of the contour curve.

Fig. 7 shows measured data of the 3D image and the profile curve of the spacer (1).

Fig. 8 is a 3D image of the spacer (7) and measurement data of the contour curve.

Fig. 9 is a 3D image of the spacer (7) and measurement data of the contour curve.

Detailed Description

Hereinafter, an embodiment of the present invention will be described with reference to fig. 1 to 3. Fig. 1 is a vertical sectional view of a main part of the heat insulating container cut at an angle of 120 degrees perpendicularly (in the axial direction) to the axial center (central axis) CL, and fig. 2 is a perspective view of the spacer. Fig. 3 is an enlarged cross-sectional view schematically showing the surface of the spacer.

As shown in fig. 1, the heat insulating container 1 includes: an inner glass container 2; an outer glass container 3 surrounding the outer side of the inner container 2 and connected to the inner container 2 at an opening 1 h; and a spacer 10 disposed between the inner container 2 and the outer container 3 so as to be in contact with both the containers. Further, a space 4 enclosed by the inner container 2 and the outer container 3 is set to be vacuum.

In the production of the heat insulating container 1, the inner glass container 2 and the outer glass container 3 are connected to form a space 4 between the two containers. Then, the space 4 between both containers is evacuated from an exhaust part 3e provided at the bottom side of the outer container 3, and the exhaust part 3e is closed to be set in vacuum.

Here, before the two

containers

2 and 3 are stacked, the separator 10 is bonded to the outer surface of the bottom portion 1a of the inner container 2 with an adhesive. The spacers 10 are arranged in 3 pieces so as to surround the axial center CL of the inner container 2 at a uniform interval, and form the space 4 between the outer container 3 and the inner container 2. Then, the outer container 3 is disposed so as to cover the inner container 2, and is molded by being pressed along the inner container 2 while being heated as appropriate. Then, the exhaust portion 3e is exhausted, and the exhaust portion 3e is heat-welded to maintain the vacuum of the space 4. The heat insulating container 1 thus manufactured is generally used in a state of being housed in an appropriate outer package 20.

The number of the spacers 10 may be changed as appropriate depending on the size of the heat insulating container, and is preferably 2 or more, more preferably 3 to 10, and still more preferably 3 to 5. Particularly, 3 are preferable because, on the one hand, the relative positions of the inner container 2 and the outer container 3 are highly stable, and on the other hand, the positions where heat conduction occurs can be reduced as much as possible.

As shown in fig. 2, the spacer 10 has a predetermined thickness d2 and is formed as a columnar member having a contact surface 10s on both the front and back surfaces. The contact surface 10s is disposed so as to be in contact with the inner container 2 and the outer container 3. The contact surface 10s is bonded to the inner container 2 by applying an adhesive to one or both surfaces thereof as described above, and is disposed between the contact surface and the bottom 1b of the outer container 3.

The spacer 10 is made of a calcium silicate-based material or a diatomaceous earth-based material, and is a material having a load of 175N or less required for compression of 0.1mm at a compression rate of 0.1 mm/min.

The calcium silicate material in the present invention is a material containing calcium silicate, and contains calcium oxide (CaO) and silicic acid (SiO)₂) A hydrate of the bound compound. The calcium silicate may, for example, comprise xonotlite, tobermorite, wollastonite, other calcium silicate hydrates and mixtures thereof.

As the calcium silicate material, more preferably, a calcium silicate material described in jp-a-55-167167 is obtained as follows: dewatering and molding a slurry prepared from a homogeneous mixture of the following (A) to (D), and molding the resulting product at 6kg/cm²Steaming under the above pressurized steam to obtain silicic acidThe material is reacted with lime raw material and then heated to 330 ℃ or higher under atmospheric pressure to remove water released from the formed product.

(B) 50-170 parts by weight of xonotlite obtained by hydrothermal synthesis

(C) 15 to 150 parts by weight of fibrous wollastonite

(D) 2-8 times of total solid water

Examples of the lime material, the silicic acid material, the xonotlite and the fibrous wollastonite include those described in Japanese patent application laid-open No. 55-167167, and the same is preferred. The calcium silicate material can be obtained by the method disclosed in Japanese patent laid-open publication No. 55-167167.

The calcium silicate-based material may further contain reinforcing fibers, additives, and the like.

The separator 10 can be formed by cutting or punching a plate-like calcium silicate material into a desired shape. The plate-like calcium silicate material includes Lumiboard, Ecolux, NA Luxe, HILAC, Mitsubishi Histika ((R))

)、Chiyoda Cera Board(

) Etc. are being marketed in the form of calcium silicate boards.

The diatomaceous earth material in the present invention is a material containing diatomaceous earth, and may further contain reinforcing fibers, additives, and the like. Diatomaceous earth is soft rock or soil mainly composed of fossils of shells of diatoms, which is one kind of algae, and contains silica as a main component, and in addition to silica, alumina, iron oxide, oxides of alkali metals, and the like may be contained. The diatomaceous earth material is commercially available, and a plate-like diatomaceous earth material can be formed into a desired shape by cutting or punching.

While calcium silicate-based materials and diatomaceous earth-based materials have been conventionally considered to be hard and unsuitable as cushioning members, in the present invention, calcium silicate-based materials having a load of 175N or less required for compression at a compression rate of 0.1 mm/min to 0.1mm are used as the spacers 10. The load required for compressing the separator 10 at a compression rate of 0.1 mm/min by 0.1mm is preferably 10N to 175N, more preferably 45N to 175N, and still more preferably 45N to 120N. By setting the load required for compression of 0.1mm at a compression rate of 0.1 mm/min to 175N or less, it is possible to prevent breakage when a double container is manufactured by inserting the inner container 2 into the outer container 3 in the manufacturing of the heat insulating container.

The double container is manufactured, for example, in the following manner: the outer surface of the bottom of the inner container is bonded with a spacer by an adhesive, and the inner container with the spacer bonded to the outer surface of the bottom is inserted into the outer container. When the spacer bonded to the inserted inner container is in contact with the outer container, if the load required for compressing 0.1mm at a compression rate of 0.1 mm/min is 175N or less, the buffer function by the spacer 10 is exhibited, and the effect of preventing the inner container 2 and the outer container 3 from being damaged can be exhibited.

The material of the spacer 10 in the present invention is preferably a calcium silicate material.

The load required for compressing the separator 10 by 0.1mm at a compression rate of 0.1 mm/min can be adjusted by appropriately changing the composition, shape, contact surface condition, and the like of the calcium silicate material.

The shape of the separator 10 is not particularly limited, but in the present embodiment, the separator 10 has a cylindrical shape, and the diameter is preferably 6.6 to 7.0mm, and more preferably 6.7 to 6.9 mm. The thickness (height) of the spacer 10 is preferably 3.6 to 4.2mm, and more preferably 3.7 to 4.0 mm. By setting in this manner, the spacer 10 can allow a displacement amount for compression of 0.05mm or more. Therefore, even if the distance between the inner container 2 and the outer container 3 is narrowed by 0.05mm or more (the upper limit is about 6mm) by a heat treatment such as an annealing treatment in the production of the heat insulating container, the spacer 10 is not broken, and the breakage of the inner container 2 and/or the outer container 3 can be suppressed.

As shown in fig. 3, spacer 10 preferably has a contact surface 10s formed as a concave-convex surface on at least one of the surfaces that contact inner container 2 and outer container 3.

The following spacers 10 can be made: the calcium silicate sheet is polished to impart unevenness thereto, and then the uneven surface is formed by cutting or punching. The calcium silicate sheet may be ground after cutting or punching. The contact surface 10s may be formed into a concave-convex surface having a desired roughness by using sandpaper (e.g., 120, 80, or preferably 30) or the like.

When the calcium silicate material is molded into a plate shape, the uneven surface may be formed by transferring the uneven shape with a die or the like.

The surface roughness of the contact surface 10s is more preferably 20 to 50 μm, and still more preferably 20 to 45 μm in terms of the arithmetic average height Sa.

If the surface roughness of the contact surface 10s is within the above range as measured by the arithmetic mean height Sa, a sufficient cushioning function can be exhibited when the separator bonded to the inner container is brought into contact with the outer container during the production of the heat insulating container.

The arithmetic average height Sa is a parameter obtained by extending the arithmetic average roughness Ra, which is a two-dimensional roughness parameter, into three dimensions, and is a three-dimensional roughness parameter (three-dimensional height direction parameter). The arithmetic mean height can be calculated from the data of the surface shape measured using a laser microscope or the like according to the method described in ISO standard (ISO 25178).

The surface roughness Ra of at least one of contact surfaces 10s of the separator 10, which contact the inner container 2 or the outer container 3, is preferably 20 to 200 [ mu ] m, and more preferably 25 to 50 [ mu ] m.

The surface roughness Ra is a surface roughness according to JIS B0601: 2013, and calculating the arithmetic average roughness.

The maximum height Rz is preferably 70 to 250 μm, more preferably 130 to 230 μm.

The maximum peak height Rp is preferably 30 to 200 μm, more preferably 35 to 150 μm, and further preferably 45 to 120 μm.

The maximum valley depth Rv is preferably 30 to 200 μm, more preferably 35 to 170 μm, and still more preferably 40 to 150 μm.

The average height Rt is preferably 60 to 300 μm, more preferably 100 to 250 μm, and further preferably 130 to 230 μm.

The ten-point average roughness RzJIS is preferably 50 to 150 μm, more preferably 60 to 120 μm.

The maximum height Sz is preferably 150 to 300 μm, and more preferably 170 to 300 μm.

The aspect ratio Str of the surface texture is preferably 0.1 to 0.35, more preferably 0.1 to 0.3.

Spc, which is the arithmetic mean curvature of the peak apex, is preferably 4.0 to 7.0(1/mm), more preferably 5.0 to 6.5 (1/mm).

The spreading area ratio Sdr of the interface is preferably 0.01 to 0.1, and more preferably 0.02 to 0.05.

The maximum height Rz, the maximum peak height Rp, the maximum valley depth Rv, the average height Rt, the ten-point average roughness RzJIS are all in accordance with JIS B0601: 2013. The maximum height Sz, the aspect ratio Str of the surface texture, the arithmetic mean curvature of the peak top Spc, and the expansion area ratio Sdr of the interface can be obtained according to ISO 25178.

In this way, the contact surface 10s of the spacer 10 that contacts the inner container 2 or the outer container 3 is formed as an uneven surface, and the contact state between the inner container 2 or the outer container 3 and the contact surface 10s is an infinite number of point contacts (see fig. 3 (a)). As a result, it is possible to estimate that the buffer function is favorably affected. This is because: when an impact is applied to the spacer 10 (an impact in the direction of the arrow shown in fig. 3 b), for example, the top 11t of the convex portion in point contact with the inner container 2 collapses as shown in fig. 3 b. As a result, the convex portion is broken to exhibit a cushioning function. On the other hand, since the spacer itself is made of a hard material, it is not largely deformed, and deformation such as breakage of the connection portion 6 of the opening portion 1h does not occur, and an effective cushioning effect can be exhibited.

The load required for compressing the separator 10 by 0.5mm at a compression rate of 0.1 mm/min is preferably 1500N or more, and more preferably 1800N to 2200N. By setting the load required for compression of 0.5mm at a compression rate of 0.1 mm/min to 1500N or more, a heat-insulating container having further excellent impact strength can be produced. When a large impact such as dropping is applied to the heat insulating container, the impact can be absorbed without causing a large deformation in the connection portion between the inner container 2 and the outer container 3, and as a result, for example, an effect of preventing the connection portion 6 between the inner container 2 and the outer container 3 from being broken can be exhibited.

When the heat insulating container is broken by an impact such as dropping, it is presumed that the breakage is caused by the support form of the inner container 2. That is, at the time of dropping of the heat insulating container 1 or the like, since the mass of the content W in the container (inside of the inner container 2) is supported by the inner container 2 and the inner container 2 is supported by the connection portion 6 with the outer container 3 and the spacer 10 of the bottom portion 1b on the side opposite to the connection portion 6, stress associated with the dropping is likely to concentrate on the connection portion 6 with the outer container 3 of the inner container 2. Here, it is considered that, in the past, if the spacer 10 is hard, there is a fear of breakage of the contact portion between the spacer 10 and the inner container 2, and therefore, a material having relatively flexibility is preferable. However, if the spacer 10 is made of a flexible material, the amount of elastic deformation increases when the product is dropped, and stress concentration in the connection portion 6 cannot be suppressed, and it is considered that the connection portion 6 is broken in many cases. Since the separator 10 of the present embodiment has hardness of a specific value or more, stress concentration in the connecting portion 6 can be suppressed, and a heat insulating container having excellent impact strength can be obtained.

As described above, by using the separator 10 of the present embodiment, which is preferably based on the specific numerical value determined by the compression test, it is possible to suppress breakage at the time of manufacturing the heat insulating container, and to provide the heat insulating container excellent in impact strength even at the time of use.

Examples

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

[ surface roughness ]

A calcium silicate board produced by the method described in jp 55-167167 a was ground with a sandpaper of #24 and then subjected to punching, thereby preparing a calcium silicate material separator (1) having a shape shown in fig. 2. The dimensions were 6.8mm in diameter and 3.8mm in thickness. The surface roughness was measured for 10 of the prepared calcium silicate-based material separators (1) (samples 1-1 to 1-10) (in accordance with JIS B0601: 2013 and ISO 25178, the surface roughness Ra, the maximum height Rz, the maximum peak height Rp, the maximum valley depth Rv, the average height Rt, and the ten-point average roughness RzJIS were measured for the region indicated by the arrow connecting 2 × marks in fig. 4, and the arithmetic average height Sa, the maximum height Sz, the aspect ratio Str of the surface property, the arithmetic average curvature Spc of the peak apex, and the developed area ratio Sdr of the interface were measured for the region 1 in fig. 5), and are shown in table 1.

The measurement was carried out using a non-contact 3D measuring instrument (VR-3000, manufactured by Keyence).

Except that the calcium silicate board was processed without polishing, the calcium silicate-based material separator (7) was prepared in the same manner as described above, and the surface roughness was measured for 10 of them (samples 2-1 to 2-10) and shown in table 1.

Fig. 6 to 9 show the measurement data of the 3D image and the profile curve of each sample.

TABLE 1

[ example 1 ]

A heat insulating container made of glass is produced by using a spacer (1) made of a calcium silicate material.

The separator (1) used was a separator having a shape shown in fig. 2 obtained by grinding a calcium silicate board produced by the method described in jp 55-167167 a with a #24 sandpaper and then punching, and the dimensions were set to 6.8mm in diameter and 3.8mm in thickness.

As a result of the compression elasticity test (test condition 1) of the separator (1), the load required for compressing 0.1mm at a compression rate of 0.1 mm/min was about 100N.

(test conditions 1)

Testing machine: techno Graph TG-10kN manufactured by Minebea corporation

Compression speed: 0.1 mm/min

Compression distance: from contact with the test specimen until compression to 0.2mm

Contact position: the test was started from the position where 1N was applied to the test sample

Test fixture:

a load sensor: 5000N

A clamp: diameter of 100mm × 25mm

Further, as a result of the compression elasticity test (test condition 2) of the separator (1), the load required for compressing 0.5mm at a compression rate of 0.1 mm/min was 1500N.

(compression elasticity test apparatus and test conditions 2)

Testing machine: techno Graph TG-10kN manufactured by Minebea corporation

Compression speed: 0.1 mm/min

Compression distance: from contact with the test specimen until compression to 1.0mm

Test fixture:

a load sensor: 5000N

A clamp: diameter of 100mm × 25mm

As shown in FIG. 1, 1319 heat-insulating containers were produced, in which the height (H) was 180mm, the maximum diameter (D1) was 160mm, the inner diameter (D2) of the opening was 45mm, the outer diameter (D3) of the opening was 65mm, and the thickness (D4) of the container glass was 1.5 mm.

3 spacers of the spacer (1) are adhered to the bottom surface of the inner container in advance, the inner container is placed in the outer container, in this state, the inner container is molded by pressing the opening while heating the opening, and the heat-insulating container is manufactured by exhausting gas from the exhaust part and heat-welding the exhaust part.

An adhesive was used to fix the separator, and 0.015g of each adhesive was applied to one surface of the separator.

Of the 1319 heat-insulating containers produced, 3 were broken.

A drop test was performed under the following conditions using 5 heat-insulating containers manufactured in the above-described manner.

The outer casing was made of metal, and the bottom of the finished container was set to face the floor from a height of 0.5m in a state where the opening was closed with a lid and 2.2 liters of water was added as a content, and the container was dropped onto a 30 mm-thick wicker board laid on a cement floor.

Of the 5 heat-insulating containers of the present invention, 0 were broken by the drop test.

[ examples 2 and 3, comparative examples 1 to 4 ]

The heat-insulating containers of examples 2 and 3 and comparative examples 1 to 4 were produced in the same manner as in example 1 except that the separators were changed to those shown in table 2, and a drop test was performed.

TABLE 2

In addition, although the above embodiment has described the heat insulating container using the spacer made of the calcium silicate-based material, the same effect can be obtained even if the calcium silicate-based material is replaced with the diatomaceous earth-based material.

While one embodiment of the present invention has been described above, the present invention is not limited to this, and can be modified as appropriate. The size and shape, the number and the position of the spacers are not particularly limited as long as the spacers have a specific hardness and do not affect the heat insulating property. For example, in the above-described embodiment, the spacer is formed into a cylindrical shape, but may be formed into a shape other than a cylindrical shape. In addition, the shape of the heat insulating container is not limited at all by the shape shown in fig. 1.

Industrial applicability

The present invention has been described in detail and with reference to specific embodiments thereof, but it will be apparent to one skilled in the art that various changes and modifications can be added without departing from the spirit and scope thereof.

The present application was made on the basis of Japanese patent application No. 2016-187513 (Japanese application No. 2016-187513), filed on 9/26/2016, the contents of which are incorporated herein by reference.

Description of the symbols

1 Heat insulating container

2 inner container

3 outer container

4 space

6 connecting part

10 spacer

10s contact surface

CL center shaft

W content

Claims

1. An insulated container comprising: an inner container made of glass; an outer container made of glass surrounding the outer side of the inner container and connected to the inner container at an opening portion; and a separator arranged between the inner container and the outer container in contact with the two containers, wherein a space surrounded by the inner container and the outer container is set to be vacuum,

the separator is made of a calcium silicate material, at least one of the surfaces of the separator in contact with the inner container and the outer container is formed into a concave-convex surface, and the load required for compressing the separator by 0.1mm at a compression speed of 0.1 mm/min is 175N or less.

2. The heat-insulating container according to claim 1, wherein the surface roughness of at least one of the surfaces of the separator in contact with the inner container and the outer container is 20 to 50 μm in terms of the arithmetic average height Sa.

3. The heat-insulating container according to claim 1 or 2, wherein the load required for compressing the separator by 0.5mm at a compression rate of 0.1 mm/min is 1500N or more.

4. The heat-insulating container according to claim 1 or 2, wherein the calcium silicate-based material is obtained by: dewatering and molding a slurry prepared from a homogeneous mixture of the following (A) to (D), and molding the resulting product at 6kg/cm²Steaming under the above-mentioned pressurized steam to react silicic acid raw material and lime raw material, heating to 330 deg.C or higher under atmospheric pressure to remove water released from the molded article,

(A)CaO/SiO₂100 parts by weight of a mixture of a lime raw material and a silicic acid raw material in a molar ratio of 0.6 to 1.2

(B) 50-170 parts by weight of xonotlite obtained by hydrothermal synthesis

(C) 15 to 150 parts by weight of fibrous wollastonite

(D) 2-8 times of the total solid content of water.

5. The heat-insulating container according to claim 3, wherein the calcium silicate-based material is obtained by: dewatering and molding a slurry prepared from a homogeneous mixture of the following (A) to (D), and molding the resulting product at 6kg/cm²Steaming under the above-mentioned pressurized steam to react silicic acid raw material and lime raw material, heating to 330 deg.C or higher under atmospheric pressure to remove water released from the molded article,

(B) 50-170 parts by weight of xonotlite obtained by hydrothermal synthesis

(C) 15 to 150 parts by weight of fibrous wollastonite

(D) 2-8 times of the total solid content of water.