JP2010255805A - Vacuum heat insulating material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vacuum heat insulating material having excellent heat insulating performance for a long time. <P>SOLUTION: The vacuum heat insulating material 1 is formed by sealing in a decompressed state a core material 2 and an absorbent 3 between two rectangular outer covering materials 4 of which thermal welding layers 7 are arranged opposite to each other, and by thermal welding together the outer peripheral parts of three sides near the peripheral edges of the two outer covering materials 4 covering the core material 2. In a sealing part 8 where the outer peripheral parts of the outer covering materials 4 are thermal welded to each other, an irregular pattern 9 which the surface of one outer covering material 4 located in the sealing part 8 has is formed so that a cross section of the sealing part 8 which passes through a point on a recessed part also passes over a projected part. Since the thickness of the thermal welding layer 7 at the recessed part is thinner than that at the peripheral parts of the recessed part, crack generation and breakage at a thin part 11, which restricts the amount of atmospheric gas intruded from an end surface of the peripheral edge of the outer covering material 4 through the sealing part 8, rarely arise. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a vacuum heat insulating material in which a core material is hermetically sealed between two outer cover materials facing each other with heat-welding layers.

  In recent years, as a measure against global warming, which is a serious environmental problem, there has been an active movement to save energy in home appliances, equipment and buildings such as houses, and a vacuum that has an excellent thermal insulation effect over the long term. Insulation is more demanded than ever.

  The vacuum heat insulating material is a material in which a core material having fine voids such as glass wool or silica powder is covered with a jacket material having gas barrier properties, and the inside of the jacket material is sealed under reduced pressure. A vacuum heat insulating material enables expression of a high heat insulating effect by keeping the inner space in a high vacuum and reducing the amount of heat transmitted through the gas phase as much as possible. Therefore, a technique for maintaining a high degree of vacuum inside the vacuum heat insulating material is extremely important in order to exhibit the excellent heat insulating effect over a long period of time.

  As a method for maintaining the degree of vacuum inside the vacuum heat insulating material, a method in which a gas adsorbent or a moisture adsorbent is sealed under reduced pressure inside the vacuum heat insulating material together with the core material is generally used. As a result, residual moisture released from the fine gaps in the core material into the vacuum insulation after vacuum packaging, or atmospheric gases such as water vapor and oxygen that permeate through the jacket material from the outside and permeate into the vacuum insulation over time. Can be removed.

  However, considering the adsorption capacity of existing adsorbents, it can be said that the use of adsorbents alone is not sufficient to provide vacuum insulation that maintains a high thermal insulation effect over the long term. It is necessary to take measures to control the amount of atmospheric gas that is generated.

  Here, a gas path entering from the outside air into the vacuum heat insulating material will be described.

  The vacuum heat insulating material is usually a three-way sealing bag that is formed by superposing two rectangular outer covering materials and heat-sealing the outer peripheral portions in the vicinity of the three sides of the outer covering material. It is manufactured by inserting the core material from the opening and thermally welding the opening of the three-side seal bag while evacuating the inside of the bag of the jacket material using a vacuum packaging machine.

  The outer cover material is usually a heat-welded layer made of a thermoplastic resin such as low density polyethylene in the innermost layer, a gas barrier layer made of a material having a barrier property such as an aluminum foil or an aluminum vapor deposited film in the intermediate layer, and an outermost layer in the outer layer. Uses a laminated film obtained by laminating a surface protective layer such as a nylon film or a polyethylene terephthalate film through an adhesive.

  In this case, the atmospheric gas that permeates from the outside air into the vacuum heat insulating material is a component that permeates through the pinholes of the aluminum foil on the surface of the jacket material or the gaps between the vapor deposition layers, and the heat-welded layer on the edge surface of the jacket material. Are classified into two types, that is, a component that penetrates from the exposed portion to the inside through the sealing portion.

  Of these, the thermoplastic resin constituting the heat-welded layer has extremely high gas permeability and moisture permeability compared to the gas barrier layer. Most of the material is transmitted through the sealing portion to the inside from the exposed portion of the heat-welded layer on the end surface of the peripheral edge of the workpiece.

  Therefore, in order to provide a vacuum heat insulating material having excellent heat insulating performance over a long period of time, it is indispensable to suppress the amount of atmospheric gas permeation from the portion where the heat-welded layer on the edge surface of the outer jacket material is exposed. Techniques have been a challenge.

  In response to this problem, there has been reported a vacuum heat insulating material provided with a thin portion in which a part of the heat-welded layer in the sealing portion is thin (see, for example, Patent Document 1).

  FIG. 10 is a cross-sectional view of a conventional vacuum heat insulating material disclosed in Patent Document 1, and FIG. 11 is a plan view of the conventional vacuum heat insulating material disclosed in Patent Document 1.

  As shown in FIG. 10, the conventional vacuum heat insulating material 101 disclosed in Patent Document 1 includes a heat welding layer 103 positioned in a sealing portion 105 of an outer covering material 104 having a gas barrier layer 102 and a heat welding layer 103. Some are thin. As shown in FIG. 11, the thin-walled portion 106 is formed so as to surround the entire circumference of the jacket material 104.

  The structure of the conventional vacuum heat insulating material 101 is such that the permeation resistance of gas entering through the heat-welded layer 103 from the end surface of the outer periphery of the outer covering material 104 increases in the thin wall portion 106 and suppresses gas intrusion into the interior for a long time. It is said that excellent heat insulation performance can be demonstrated over a wide range.

Japanese Utility Model Publication No. 62-141190

  In the configuration of the conventional vacuum heat insulating material 101, the shape of the thin wall portion 106 as viewed from above is not described in detail, but as shown in FIG. 11, the thin wall portion 106 reaches the end of the vacuum heat insulating material 101. In the case of being formed in such a substantially linear shape, when a force perpendicular to the plane including the substantially linear thin portion 106 is applied to the sealing portion 105 during handling of the vacuum heat insulating material 101, the heat-welded layer 103 becomes thin. The sealing portion 105 is easily bent along the thin-walled portion 106 having low strength, and cracks are generated in the layer (usually the gas barrier layer 102) laminated on the outer layer side from the heat-welded layer 103, and the covering material 104 is torn. It tends to occur.

  As described above, in the cross section of the sealing portion 105, when there is a cross section including only the thin portion 106, the load in the direction perpendicular to the cross section concentrates on the thin portion 106, and the outer cover material in the thin portion 106. There is a problem that cracks and tears are likely to occur in 104, the penetration of atmospheric gas components into the vacuum heat insulating material 101 is promoted in the thin wall portion 106, and the high heat insulating performance of the vacuum heat insulating material 101 cannot be maintained.

  In view of the above-described conventional problems, the present invention provides a vacuum heat insulation that maintains excellent heat insulation performance over a long period of time, in which a thin portion of a heat-welded layer provided in a sealing portion hardly generates cracks or ruptures of a jacket material. The purpose is to provide materials.

  In order to achieve the above-described object, the vacuum heat insulating material of the present invention includes two jacket materials that cover the core material by sealing the core material under reduced pressure between the two jacket materials facing the heat-welded layers. In the vacuum heat insulating material in which the outer peripheral portions in the vicinity of the peripheral edge are thermally welded, the concave / convex pattern on the surface of one outer jacket material located on the sealing portion in which the outer peripheral portions of the outer jacket material are thermally welded is If the cross section of the sealing portion passes through the point, it is formed so that it also passes through the point on the convex portion, and the thin portion where the thickness of the heat welding layer is thinner than the peripheral portion of the concave portion is located in the concave portion. It is characterized by being.

  In the above configuration, first, in the sealing portion where the outer peripheral portions of the jacket material are thermally welded to each other, the thin portion of the heat-welded layer is provided by providing a thin-walled portion in which the thickness of the outer shell material surface heat-welded layer is locally thin. In this case, since the permeation area of gas and moisture entering from the end surface of the outer periphery of the jacket material is reduced and the permeation resistance is increased, the amount of gas and moisture permeating into the vacuum heat insulating material over time is suppressed, and it is excellent for a long time. Insulation performance can be demonstrated.

  Further, the strength of the sealing portion is locally reduced in the thin portion due to the thinning of the heat-welded layer, but the uneven pattern formed on the surface of one outer jacket material located in the sealing portion is a point on the concave portion. If the cross section of the sealing portion passes through the convex portion, it is formed so as to pass over the convex portion. Because it is adjacent to the high strength sealing part, the thin part located in the concave part is supported by the sealing part located in the convex part located nearby, and the external force received by the sealing part during handling is thin. It is difficult to concentrate on the portion, and cracks and breaks in the thin-walled portion of the heat-welded layer and the jacket material in the vicinity thereof are extremely difficult to occur.

  As described above, it is possible to provide a vacuum heat insulating material that maintains excellent heat insulating performance over a long period of time, in which the outer shell material is hardly cracked or broken in the thin portion of the heat-welded layer provided in the sealing portion and in the vicinity thereof. .

  According to the present invention, by providing the thin portion where the thickness of the heat-welding layer of the sealing portion is locally thin, the gas and moisture amount entering from the end face of the outer periphery of the outer jacket material are suppressed, and the thermal insulation layer is excellent over a long period of time. Insulation performance can be demonstrated. In addition, since the thin portion where the strength of the sealing portion locally decreases in the sealing portion is not easily affected by external force, the occurrence of cracks or breakage in the jacket material located in the thin portion of the heat-welded layer Is extremely difficult to occur.

  As described above, it is possible to provide a vacuum heat insulating material that maintains excellent heat insulating performance over a long period of time, in which the outer cover material is hardly cracked or broken in the thin portion of the heat-welded layer provided in the sealing portion.

Sectional drawing of the vacuum heat insulating material in Embodiment 1 of this invention The top view of the vacuum heat insulating material in Example 1 of the embodiment The top view of the vacuum heat insulating material in Example 2 of the embodiment The top view of the other example of the vacuum heat insulating material in the embodiment The top view of another example of the vacuum heat insulating material in the embodiment The top view of another example of the vacuum heat insulating material in the embodiment Sectional drawing of the sealing part containing the thin part of the vacuum heat insulating material in Example 1 and Example 2 of the embodiment The top view of the vacuum heat insulating material in the comparative example 2 Plan view of vacuum heat insulating material in Comparative Example 3 Cross section of conventional vacuum insulation Plan view of conventional vacuum insulation

  The invention of the first vacuum heat insulating material is an outer peripheral portion in the vicinity of the peripheral edges of the two jacket materials that cover the core material with the core material sealed under reduced pressure between the two jacket materials facing the heat-welded layers. In the vacuum heat insulating material in which the outer peripheral portions of the outer cover material are heat-welded with each other, the uneven pattern of one outer cover material surface located in the sealing portion in which the outer peripheral portions of the outer cover materials are heat-welded is passed through the point on the concave portion. If it is a cross section of the stop portion, it is formed so as to pass through a point on the convex portion, and the thin portion where the thickness of the heat welding layer is thinner than the peripheral portion of the concave portion is located in the concave portion. .

  In the above configuration, first, in the sealing portion where the outer peripheral portions of the jacket material are thermally welded to each other, the thin portion of the heat-welded layer is provided by providing a thin-walled portion in which the thickness of the outer shell material surface heat-welded layer is locally thin. In this case, since the permeation area of gas and moisture entering from the end surface of the outer periphery of the jacket material is reduced and the permeation resistance is increased, the amount of gas and moisture permeating into the vacuum heat insulating material over time is suppressed, and it is excellent for a long time Insulation performance can be demonstrated.

  Further, the strength of the sealing portion is locally reduced in the thin portion due to the thinning of the heat-welded layer, but the uneven pattern formed on the surface of one outer jacket material located in the sealing portion is a point on the concave portion. If the cross section of the sealing portion passes through the convex portion, it is formed so as to pass over the convex portion. Because it is adjacent to the high strength sealing part, the thin part located in the concave part is supported by the sealing part located in the convex part located nearby, and the external force received by the sealing part during handling is thin. It is difficult to concentrate on the portion, and cracks and breaks in the thin-walled portion of the heat-welded layer and the jacket material in the vicinity thereof are extremely difficult to occur.

  As described above, it is possible to provide a vacuum heat insulating material that maintains excellent heat insulating performance over a long period of time, in which the occurrence of cracks and breakage hardly occur in the thin portion of the heat-welded layer provided in the sealing portion.

  Next, constituent materials of the vacuum heat insulating material will be described.

  The heat welding layer constituting the jacket material is not particularly specified, but a low density polyethylene film, a linear low density polyethylene film, a high density polyethylene film, a medium density polyethylene film, a polypropylene film, a polyacrylonitrile film, etc. These thermoplastic resins or mixed films thereof can be used.

  The core material is not particularly specified for its type, but is a porous body having a gas layer ratio of about 90%, and is open-celled such as urethane foam, styrene foam, phenol foam, glass wool, rock wool, alumina fiber, Conventionally known core materials such as fiber bodies such as silica-alumina fibers, powders such as pearlite, wet silica, and dry silica can be used.

  The laminate adhesive used for the jacket material is not particularly specified, but a conventionally known laminate adhesive such as a two-component curable urethane adhesive or an adhesive for laminate such as an epoxy resin adhesive is used. it can.

  The two jacket materials are the two jacket materials that are heat-sealed in the sealing portion where the jacket materials are thermally welded to each other. It means that it is located, and does not specify the bag shape of the jacket material.

  Here, the bag shape of the jacket material is not particularly specified, and conventionally known bag shapes such as a four-side seal bag, a gusset bag, a three-side seal bag, and a pillow bag can be used.

  The two jacket materials are the two jacket materials that are heat-sealed in the sealing portion where the jacket materials are thermally welded to each other. It means that it is located, and does not specify the bag shape of the jacket material.

  The concavo-convex pattern is a pattern formed on at least a part of the sealing portion due to a difference in thickness of the heat-welded layer, and is a pattern when viewed from one of the two outer cover material surfaces located in the sealing portion. Point to.

  Here, the concavo-convex pattern does not need to be the same pattern as seen from both of the two outer cover material surfaces of the sealing portion where the concavo-convex pattern is located. It only has to be formed.

  Further, the surface of the jacket material refers to the surface portion of the outermost layer of the jacket material.

In addition, a recessed part refers to the part which the outer covering material surface is dented in the heat welding layer side among the uneven | corrugated pattern formed in the outer covering material surface.
Moreover, when the uneven | corrugated pattern is formed in the jacket material surface of both surfaces which a sealing part has, the recessed part which has a thin part should just be included in any one uneven | corrugated pattern.

  The convex portion refers to the entire portion of the uneven pattern formed on the surface of the jacket material where the surface of the jacket material is convex on the side opposite to the heat-welded layer. It includes a portion with a thickness gradient in which the thickness of the weld layer increases.

  Further, if the concavo-convex pattern is a cross-section of the sealing portion passing through a point on the concave portion, the concavo-convex pattern is formed so as to also pass over the convex portion. In the point group, the cross section of the sealing portion cut by a plane passing through the point group included in the concave portion means that it passes through any of the point groups included in the convex portion on the same jacket material surface. Yes, it means that every cross section of the sealing portion cut by a plane passing through the point group included in the concave portion includes both cross sections of the concave portion and the convex portion.

  The invention of the second vacuum heat insulating material is characterized in that the concavo-convex pattern in the first invention has the concave portion surrounded by the convex portion.

  In the above configuration, the thin portion located in the concave portion surrounded by the convex portion is supported by the relatively thick heat-welded layer located in the peripheral convex portion, and is thin even with respect to external force from all directions. It is difficult for the force to concentrate on the portion, and cracking and breakage of the jacket material in the thin wall portion of the heat-welded layer are extremely difficult to occur.

  In addition, the recessed part enclosed by the convex part is a recessed part from which the boundary line which exists on the outer covering material of a recessed part and a convex part becomes a closed line in the uneven | corrugated pattern which the outer jacket material surface located in a sealing part has And means a state in which a convex portion exists around the entire concave portion.

  In the invention of the third vacuum heat insulating material, in the first or second invention, in the cross section perpendicular to the outer periphery of the outer cover material of the sealing portion passing through the point on the concave portion, the sealing portion is the thin-walled portion. Having at least two or more.

  In the case of having a plurality of thin portions in the direction perpendicular to the outer periphery of the jacket material, which is the direction in which atmospheric gas penetrates into the vacuum heat insulating material, compared to the case where there is only one thin portion, the thermal weld layer in each thin portion Since the same effect can be obtained even if the thickness is increased, the decrease in the strength of the jacket material and the seal strength due to the thinned heat-welding layer is alleviated, and the risk of cracks and breakage in the thin portion is reduced.

  Furthermore, in the thin part, the thickness of the heat-welded layer is thin compared to other parts of the sealing part, and the sealing strength is reduced, for example, a state in which glass fiber or silica powder as a core material is sandwiched in the manufacturing process When the outer cover material is heat-welded, there is a concern that a heat-welding failure may occur in the thin portion.

  Since there is no resin that blocks gas permeation at the location where the thermal welding failure has occurred, the effect of suppressing gas penetration is reduced.

  As a countermeasure against this, by providing at least two or more thin portions in the direction of penetration of atmospheric gas into the vacuum heat insulating material, the influence of gas and moisture penetration promotion into the vacuum heat insulating material due to poor heat welding is mitigated. The

  The invention of the fourth vacuum heat insulating material is characterized in that the uneven pattern in any one of the first to third inventions is a lattice pattern.

  When the concavo-convex pattern is a lattice pattern, the thick convex portion of the heat-welded layer is substantially straight when viewed from the surface of the jacket material having the concavo-convex pattern in the sealing portion, and intersects the lattice shape. Since it matches, the strength of the sealing portion is kept high.

  As a result, the thin-walled portion having low strength is not easily affected by external force, and cracking or tearing of the jacket material in the sealing portion is extremely unlikely to occur.

  Also, when looking at the cross section of the sealing portion passing through the point on the concave portion, the thin wall portion and the sealing portion having a thicker heat-sealed layer than the thin wall portion are periodically arranged, Bending resistance to external force from a vertical direction becomes higher.

  In addition, if the high strength of the sealing portion can be maintained, the total area of the thin-walled portion can be increased with respect to the entire sealing portion, and the effect of suppressing gas intrusion into the vacuum heat insulating material is enhanced.

  The lattice pattern refers to a pattern composed of concave portions of the same shape periodically arranged in parallel with convex portions that are substantially linear when viewed from the surface of the outer jacket material having the concave and convex patterns, and the width and area of the convex portions. The shape and area of the recess are not particularly specified.

  The invention of a fifth vacuum heat insulating material according to any one of the first to fourth inventions is characterized in that the concave portion of the concave-convex pattern is surrounded by the convex portion.

  As already described, the thin-walled portion located in the concave portion surrounded by the convex portion is extremely unlikely to cause cracking or breaking of the outer jacket material even with respect to external force from any direction.

  When all the concave portions of the concavo-convex pattern have the above-described configuration, the effect becomes higher.

  Moreover, when the recessed part which is not surrounded by the convex part in the uneven | corrugated pattern exists, the case where the recessed part is in contact with the boundary of a sealing part and a non-sealing part, or the outer periphery of a jacket material is considered.

  When the heat-welded layer is thin at the boundary between the sealed part and the non-sealed part of the jacket material, the sealing strength at that point decreases, and the bag of the jacket material breaks during manufacturing and handling There is a fear.

  In the above configuration, the concave portion where the thin portion is located does not exist in contact with the boundary between the sealing portion and the non-sealing portion, and the sealing strength does not decrease. It's hard to get up.

  Furthermore, if the thin wall portion does not exist on the outer periphery of the outer jacket material, even the thin wall portion located on the outermost peripheral surface of the sealing member may cause cracking or tearing due to an impact on the end of the vacuum heat insulating material. It becomes extremely difficult to receive.

  In addition, the non-sealing part of a jacket material refers to the location where the jacket material is not heat-welded with the other jacket material.

  In the invention of the sixth vacuum heat insulating material, in any one of the first to fifth inventions, the thickness change of the heat-welded layer located at a boundary portion between the adjacent concave portion and the convex portion is substantially arc-shaped. It is characterized by.

  If the change in thickness of the heat-welded layer located at the boundary between the adjacent concave and convex portions is substantially arc-shaped, the jacket material follows the shape of the heat-welded layer in the vicinity of the thin portion of the sealing portion. Thus, it is difficult to generate cracks in the jacket material without bending in an arc and forming corners.

  Here, as a matter of course, it is desirable that corner portions are not formed in the whole sealing portion, not limited to the thin-walled portion and the vicinity thereof.

  Furthermore, in the thin part, the thickness of the heat-welded layer is thinner than the peripheral part, and the strength is reduced by the thickness reduction, but the heat-welded layer near the thin part at the boundary part between the adjacent concave part and convex part. As the thickness of the seal gradually increases and decreases along the arc, the strength of the sealing portion also increases and decreases continuously and smoothly, and external forces concentrate locally in the thin portion of the heat-welded layer. It is difficult to generate cracks and breaks in the thin-walled portion of the heat-welded layer and the jacket material in the vicinity thereof.

  In addition, the boundary part of an adjacent recessed part and a convex part points out the sealing part located on the boundary line of the adjacent recessed part and convex part in an uneven | corrugated pattern, and its vicinity.

  In addition, a corner | angular part refers to the site | part (part with a large curvature) used as the square shape formed with the thickness change of the heat welding layer which arises in the boundary of a thin part and its vicinity.

  The invention of a seventh vacuum heat insulating material is the invention according to any one of the first to sixth aspects, wherein the heat-welded layer of the sealing portion has a boundary surface with another layer on both sides, and the uneven pattern is formed. The wave height of the undulation of one of the boundary surfaces of the sealing portion is larger than the wave height of the undulation of the other boundary surface.

  In the concavo-convex pattern forming part where the thickness gradient of the heat-welded layer exists, the jacket material (usually the gas barrier layer) on the outer layer side of the heat-welded layer is deteriorated due to stress due to distortion along the shape of the heat-welded layer. If you want to.

  Here, by making the wave height of the waviness of the boundary surface located at the sealing portion where the concavo-convex pattern is formed larger than the wave height of the waviness of the other boundary surface, the boundary surface having a relatively small wave height Deterioration of the outer cover material on the side is slight compared to the outer cover material on the side of the boundary surface, which has a relatively large wave height, and the outer cover material with less deterioration is sealed on the other outer surface. Rigidity is maintained in such a way as to support the workpiece, and generation of cracks and breakage are hardly caused when an external force is applied.

  In addition, a boundary surface refers to the boundary surface of a heat welding layer and the other layer adjacent to a heat welding layer in a sealing part.

  Note that the wave height is the thinnest through the plane including the thinnest portion of the heat-welded layer in the thin portion located in the concave portion on the same boundary surface and the thickest portion of the heat-welded layer located in the adjacent convex portion. This refers to the distance between the plane including the part and the plane parallel to it.

  The invention of the eighth vacuum heat insulating material is the invention according to any one of the first to seventh aspects, wherein a part of the convex portion formed between the concave portions adjacent to each other formed in the continuous sealing portion. The thickness of the heat-welded layer is thicker than the sum of the thicknesses of the heat-welded layers included in two or more unsealed portions of the jacket material.

  Usually, when the thin portion is not provided, the thickness of the sealing portion is substantially equal to the sum of the thicknesses of the heat welding layers respectively included in the non-sealing portions of the two jacket materials.

  When forming a plurality of thin portions in a continuous sealing portion, the resin constituting the heat-welded layer at the position of each thin portion moves outside the sealing portion and the sealing portion other than the thin portion. .

  The thickness of the heat-welded layer in the convex portion located between the concave portions adjacent to each other in the concave-convex pattern formed in the continuous sealing portion is the thickness of the heat-welded layer included in the non-sealed portion of the two jacket materials If it is thinner than or substantially equal to the sum, there are no resin movement points, so the load caused by the flow of the resin breaks the other layer adjacent to the heat-welded layer of the outer cover material located around the thin-walled part. The risk of spilling out increases.

  In the concavo-convex pattern provided in the continuous sealing portion, the thickness of the heat-sealing layer that the non-sealing portion of the two jacket materials has on at least a part of the heat-welding layer located on the convex portion formed between the concave portions Since the resin escape portion is provided in advance by setting the thickness to be thicker than the sum of the thickness, the load received by the outer cover material of the sealing portion located between the thin portions is reduced, and the outer cover is reduced. Makes material tearing extremely difficult.

  In addition, on one surface of the outer cover material having the concavo-convex pattern of the continuous sealing portion, two sheets are also provided between the concave portion located on the boundary portion side between the portion having the concavo-convex pattern and the portion having no concavo-convex pattern. It is more desirable to provide a sealing portion that is thicker than the total thickness of the heat-welded layers of the non-sealing portion of the outer cover material.

  Hereinafter, embodiments of the vacuum heat insulating material of the present invention will be described with reference to the drawings, but the same components as those described above are denoted by the same reference numerals, and detailed description thereof will be omitted. And In addition, this invention is not limited by this embodiment.

(Embodiment 1)
FIG. 1 is a cross-sectional view of a vacuum heat insulating material according to Embodiment 1 of the present invention, and FIGS. 2 to 6 show examples of plan views of the vacuum heat insulating material of the same embodiment.

  In FIG. 1, a vacuum heat insulating material 1 includes a core material 2, an adsorbent 3 disposed in the core material 2, and two rectangular outer cover materials 4 cut to the same size. The core material 2 and the adsorbent 3 are sealed under reduced pressure between the materials 4, and the outer peripheral portions in the vicinity of the peripheral edges of the two jacket materials 4 covering the core material 2 are heat-welded.

  The two jacket materials 4 are formed by laminating a surface protective layer 5, a gas barrier layer 6, and a heat welding layer 7 from the outer layer side. Further, on the peripheral side (outer peripheral portion) of the jacket material 4, there is a sealing portion 8 in which the heat-welding layers of the jacket material are melted and bonded together, and the sealing portion 8 has a thickness of the heat-welding layer 7. A difference is provided in the thickness, and the uneven pattern 9 is formed on the surface of one outer jacket material located in the sealing portion 8 due to the difference in thickness.

  The thickness of the heat-welding layer 7 located in the concave portion 10 of the uneven pattern 9 forms a thin portion 11 that is thinner than the heat-welding layer 7 in the peripheral portion of the concave portion 10.

  Here, the shape of the uneven pattern 9 in the sealing portion 8 will be described.

  When viewed from the surface of the jacket material 4, the cross section of the sealing portion 8 that passes through the point on the concave portion 10 is also configured to pass on the convex portion 12.

  Moreover, the thickness change of the heat welding layer 7 located in the boundary part of the adjacent recessed part 10 and the convex part 12 is substantially circular arc shape.

  Moreover, the heat welding layer 7 of the sealing part 8 has a boundary surface with the other layer (gas barrier layer 6) adjacent to both surfaces, and the undulation of one boundary surface of the sealing part 8 on which the concavo-convex pattern is formed. Is set to be larger than the wave height of the undulation of the other boundary surface.

  About the vacuum heat insulating material 1 comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  First, the core material 2 plays a role of forming a fine space as an aggregate of the vacuum heat insulating material 1 and forms a heat insulating portion of the vacuum heat insulating material 1 after evacuation.

  The adsorbent 3 serves to adsorb and remove residual gas components released into the vacuum heat insulating material 1 from the fine gaps of the core material 2 after vacuum packaging, and moisture and gas that enter the vacuum heat insulating material 1. .

  The jacket material 4 is obtained by laminating a thermoplastic resin, a metal foil having a gas barrier property, a resin film, and the like, and plays a role of suppressing atmospheric gas intrusion into the vacuum heat insulating material 1 from the outside.

  The surface protective layer 5 serves to prevent the outer cover material 4, particularly the gas barrier layer 6 from being damaged or torn from an external force, located on the outer layer side of the gas barrier layer 6 among the layers of the outer cover material.

  As the surface protective layer 5, a conventionally known material such as a nylon film, a polyethylene terephthalate film, or a polypropylene film can be used, and one type or two or more types may be used.

  The gas barrier layer 6 is a layer composed of one or more kinds of films having high barrier properties, and imparts excellent gas barrier properties to the jacket material 4.

  As the gas barrier layer 6, metal foil such as aluminum foil, copper foil, stainless steel foil, polyethylene terephthalate film, ethylene-vinyl alcohol copolymer film, metal atoms such as aluminum or copper, or metal oxide such as alumina or silica are used. A vapor-deposited film, a film in which a metal atom or metal oxide is vapor-deposited, or the like can be used.

  The thermal welding layer 7 welds the jacket materials 4 to each other, and in addition to the role of maintaining the vacuum inside the vacuum heat insulating material 1, the gas barrier from the piercing from the inside of the vacuum heat insulating material 1 by the core material 2 and the adsorbent 3, etc. It serves to protect the layer 6.

  The sealing portion 8 is configured by welding the heat welding layers 7 of the jacket material 4, and plays a role of blocking the inside and the outside of the vacuum heat insulating material 1.

  The concave portion 10 is a portion of the concave / convex pattern 9 where the surface of the outer covering material 4 is recessed toward the heat welding layer 7, and the thickness of the heat welding layer 7 of the sealing portion 8 is reduced to form the thin portion 11. To fulfill.

  The thin-walled portion 11 plays a role of maintaining the degree of vacuum of the vacuum heat insulating material 1 by suppressing the permeation rate of the atmospheric gas that enters the vacuum heat insulating material 1 from the end surface of the outer periphery of the jacket material 4 through the sealing portion 8. Yes.

  The convex portion 12 is a portion of the concavo-convex pattern 9 where the covering material 4 is convex on the side opposite to the inside of the vacuum heat insulating material 1, and protects the concave portion 9 where the thin portion 11 is located from external force, and In addition, it plays a role of a resin escape portion constituting the heat-welded layer 7 that has moved from the thin-walled portion 11.

  As described above, in the present embodiment, the thin portion 11 is provided at the position of the concave portion 10 in the concave-convex pattern 9 formed on the surface of the one jacket material 4 in the sealing portion 8. Since the permeation area of the gas and moisture entering from the end surface of the outer periphery of the jacket material 4 is reduced and the permeation resistance is increased, the amount of gas and moisture that permeate into the vacuum heat insulating material 1 over time is suppressed over a long period. Excellent heat insulation performance can be demonstrated.

  Further, in the vacuum heat insulating material 1 according to the present embodiment, the concavo-convex pattern 9 formed on the surface of one outer jacket material 4 located in the sealing portion 8 is a point on the outer jacket material 4 surface included in the concave portion 10. The cross section of the sealing portion 8 that passes through is configured to pass through the points on the convex portion 11, and the thin portion 11 can be seen from the cross section of the sealing portion 8 cut by a plane passing through the thin portion 11. Is adjacent to a thicker portion than the thin-walled portion 11, and the thin-walled portion 11 is supported by the thick heat-welded layer 7, thereby locally reducing the strength of the sealing portion 8 in the thin-walled portion 11. Therefore, cracks and breaks in the jacket material of the sealing portion 8 are extremely difficult to occur.

  Further, in the vacuum heat insulating material 1 according to the present embodiment, the thickness change of the heat welding layer 7 located at the boundary portion between the adjacent concave portion 9 and the convex portion 12 is substantially arcuate, and the jacket material is a thin portion. 11 where the thickness gradient of the heat-welded layer 7 is generated, bends in an arc shape along the shape of the heat-welded layer 7, and does not form corners, but concentrates on the corners of the jacket material 4. Deterioration is prevented, and cracks in the jacket material are extremely difficult to occur.

  Further, in the thin portion 11, the thickness of the heat welding layer 7 becomes thinner than the peripheral portion, and the strength of the sealing portion 8 is reduced by the thickness reduction, but the boundary between the adjacent concave portion 10 and the convex portion 12. As the thickness of the heat-welded layer 7 in the vicinity of the thin-walled portion 11 gradually increases and decreases along the arc, the strength of the sealing portion 8 also increases and decreases continuously and smoothly. In particular, since the strength of the sealing portion 8 does not decrease and the external force hardly concentrates on the boundary portion, the thin portion 11 and the covering material in the vicinity thereof are hardly cracked or broken.

  Further, in the vacuum heat insulating material 1 of the present embodiment, the heat-welded layer 7 of the sealing portion 8 has a boundary surface with another layer (gas barrier layer 6) on both surfaces, and the uneven pattern 9 is formed. The wave height of the undulation of the one boundary surface of the stop portion 8 is larger than the wave height of the undulation of the other boundary surface of the uneven pattern 9.

  In the portion where the thickness gradient of the heat welding layer 7 exists, the jacket material (the gas barrier layer 6 and the surface protective layer 5) on the outer layer side of the heat welding layer 7 is subjected to stress caused by distortion along the shape of the heat welding layer 7. Will cause deterioration.

  Therefore, the wave height of the undulation of the boundary surface (upper side in FIG. 1) located at the sealing portion 8 where the uneven pattern 9 is formed is made larger than the wave height of the undulation of the other boundary surface (lower side in FIG. 1). As a result, the deterioration of the outer cover material 4 on the boundary surface side (lower side in FIG. 1) having undulations with a relatively small wave height is the other boundary surface side (in FIG. The outer cover material 4 is slightly smaller than the outer cover material 4, and the outer cover material 4 is less deteriorated (lower in FIG. 1) in the sealing portion 8 of the outer cover material 4 (upper in FIG. 1). Rigidity is maintained in a form that supports the workpiece 4, and cracks and breakage are hardly caused when an external force is applied.

  Moreover, it is preferable that the vacuum heat insulating material 1 of this Embodiment has the sealing part 8 at least 2 or more of the recessed parts 10. FIG.

  In the thin portion 11, the thickness of the heat-welded layer 7 is thinner than that of the other portion of the sealing portion 8, and the sealing strength is reduced. For example, glass fiber or silica powder that is the core material 2 in the manufacturing process When the outer cover material 4 is heat-welded in a state where the material is sandwiched, there is a concern that a poor heat-welding may occur in the thin portion 11.

  Since there is no resin at the location where the thermal welding failure occurs, the effect of suppressing gas intrusion decreases.

  As a countermeasure, by providing at least two or more thin portions 11, the influence of gas and moisture penetration into the vacuum heat insulating material 1 due to poor heat welding is mitigated.

  In particular, when glass fiber is used as the core material 2, the core material 2 material sandwiched at the time of heat welding as an interstitial material is often heat-deformed and forms a through hole in the thin portion 11. The effect (of the present embodiment) of the present invention becomes more remarkable.

  Further, in the case where a plurality of thin portions 11 are provided, the same effect can be obtained even if the thickness of the heat welding layer 7 in the thin portion 11 is increased as compared with the case where only one thin portion 11 is provided. 11 is reduced, and the risk of occurrence of cracks in the thin portion 11 and breakage of the sealing portion 8 is reduced.

  In the present embodiment, the concavo-convex pattern 9 may be formed over the entire sealing portion 8 on one of the two outer cover material surfaces located on the sealing portion 8. It may be a part of

  In addition, the thickness of the heat welding layer 7 in each thin part 9 which the sealing part 8 has does not need to be the same.

  In addition, the curvature radius of the circular arc of the boundary surface between the heat-welding layer 7 and the other layer formed with the thickness change of the heat-welding layer located at the boundary portion between the concave portion 10 and the convex portion 12 adjacent in the concavo-convex pattern 9 is The metal foils and films used as the gas barrier layer 6 need only have a radius of curvature that does not deteriorate.

  Note that the configuration of the uneven pattern 9, that is, the areas and shapes of the recesses 10 and the protrusions 12 are not particularly specified, and the areas and shapes of the recesses need not all be equal.

  Hereafter, the detailed shape of the uneven | corrugated pattern 9 in this invention and its effect are demonstrated using an Example.

Example 1
In the first embodiment, a linear low density polyethylene film having a thickness of 50 μm is used as the heat welding layer 7, an aluminum foil having a thickness of 6 μm is used as the gas barrier layer 6, and two nylon films having a thickness of 15 μm and 25 μm are used as the surface protective layer 5. A vacuum heat insulating material 1 composed of a laminated jacket material 4, a core material 2 made of glass fiber, and an adsorbent 3 formed by enclosing calcium oxide in a ventilation wrapping material was produced.

  On the peripheral side (outer peripheral portion) of the jacket material 4, there is a sealing portion 8 in which the heat-welding layers 7 of the jacket material 4 are fused and bonded together, and the two melted surfaces located in the sealing portion 8 A concave-convex pattern 9 is formed on one of the outer jacket material surfaces (upper side in FIG. 7).

  The concavo-convex pattern 9 is formed by the thickness difference of the heat-welded layer 7 at the position of the concavo-convex pattern 9, and the thickness of the heat-welded layer 7 located in the concave portion 10 is thinner than the heat-welded layer 7 located in the periphery thereof. ing.

  It is assumed that the width of the sealing portion 8 of the vacuum heat insulating material 1 is 20 mm, and the uneven pattern 9 is formed over the entire inner portion by 1 mm from the outer peripheral side and the inner peripheral side of the sealing portion 8.

  The concave / convex pattern 9 is a lattice pattern as shown in FIG. 2, and the concave portions 10 are all surrounded by the convex portions 12.

  Furthermore, it is assumed that the shape of the concave portion 10 on the surface of the jacket material 4 is an entire square having a diagonal of 6 mm and a part thereof, and the width of the convex portion is 1.5 mm.

  The radius of curvature of the arc located at the boundary portion between the concave portion 10 and the convex portion 12 formed by the boundary surface (in FIG. 7, between the upper gas barrier layer 6 and the thermal welding layer 7) is 1.5 mm (in FIG. 7, Each wave height of the undulation at the boundary surface between the upper gas barrier layer 6 and the thermal welding layer 7 was 0.2 mm. Further, the maximum wave height of the concave portion of the other interface (in FIG. 7, the lower gas barrier layer 6 and the heat-welded layer 7) was 0.05 mm (see FIG. 7).

At this time, when the thickness of the thin wall portion 11 is 15 μm, the amount of atmospheric gas entering through the sealing portion 8 from the end surface of the outer periphery of the outer cover material 4 of the vacuum heat insulating material 1 is 3.4 × 10 ⁻¹⁵ mol / m ² / s / Pa.

  Moreover, in the sealing part 8, generation | occurrence | production of the crack was not confirmed in the aluminum foil.

  In Example 1, the core material 2 consists of glass fiber.

  When the core material 2 is a glass fiber, a penetrating pinhole from the inside of the vacuum heat insulating material 1 to the jacket material 4 due to the glass fiber is likely to occur.

  Usually, as a measure for preventing the occurrence of pinholes, it is effective to increase the thickness of the heat welding layer 7 in the innermost layer of the jacket material 4 facing the inside of the vacuum heat insulating material 1. By increasing the thickness, there is a concern that the passage cross-sectional area of the gas intrusion path that enters through the sealing portion 8 from the end face of the outer periphery of the outer cover material 4 increases.

  In the vacuum heat insulating material 1 of the first embodiment (Example 1), since the gas penetration amount can be controlled in the thin portion 9, the end surface of the outer periphery of the outer cover material 4 even if the thickness of the heat welding layer 7 is increased. Increase in the amount of gas and moisture entering from the inside through the sealing portion 8 to the inside is suppressed.

  Moreover, in Example 1, although aluminum foil (metal foil) was employ | adopted as a gas barrier layer for providing gas-barrier property to the jacket material 4, a metal foil vapor-deposits a metal atom and a metal oxide molecule on a resin film. Although the gas barrier property is excellent as compared with the gas barrier film, the stretchability and followability are inferior, so that cracks and pinholes are likely to occur, and the effect of the present invention (Embodiment 1) appears more remarkably.

(Example 2)
In the first embodiment, a linear low density polyethylene film having a thickness of 50 μm is used as the heat welding layer 7, an aluminum foil having a thickness of 6 μm is used as the gas barrier layer 6, and two nylon films having a thickness of 15 μm and 25 μm are used as the surface protective layer 5. A vacuum heat insulating material 1 composed of a laminated jacket material 4, a core material 2 made of glass fiber, and an adsorbent 3 formed by enclosing calcium oxide in a ventilation wrapping material was produced.

  On the peripheral side (outer peripheral portion) of the jacket material 4, there is a sealing portion 8 in which the heat-welding layers 7 of the jacket material 4 are fused and bonded together, and the two melted surfaces located in the sealing portion 8 A concave-convex pattern 9 is formed on one of the outer jacket material surfaces (upper side in FIG. 7).

  The concavo-convex pattern 9 is formed by the thickness difference of the heat-welded layer 7 at the position of the concavo-convex pattern 9, and the thickness of the heat-welded layer 7 located in the concave portion 10 is thinner than the heat-welded layer 7 located in the periphery thereof. ing.

  It is assumed that the width of the sealing portion 8 of the vacuum heat insulating material 1 is 20 mm, and the uneven pattern 9 is formed over the entire inner portion by 1 mm from the outer peripheral side and the inner peripheral side of the sealing portion 8.

  The concave / convex pattern 9 is a lattice pattern as shown in FIG. 2, and the concave portions 10 are all surrounded by the convex portions 12.

  Furthermore, it is assumed that the shape of the concave portion 10 on the surface of the jacket material 4 is an entire square having a diagonal of 6 mm and a part thereof, and the width of the convex portion is 1.5 mm.

  The radius of curvature of the arc located at the boundary portion between the concave portion 10 and the convex portion 12 formed by the boundary surface (in FIG. 7, the upper gas barrier layer 6 and the thermal welding layer 7) is 1.1 mm (in FIG. 7, Each wave height of the undulation at the boundary surface between the upper gas barrier layer 6 and the thermal welding layer 7 was 0.18 mm. Further, the maximum wave height of the concave portion of the other interface (in FIG. 7, the lower gas barrier layer 6 and the heat-welded layer 7) was 0.05 mm (see FIG. 7).

At this time, when the thickness of the thin portion 11 is 30 μm, the amount of atmospheric gas entering through the sealing portion 8 from the end surface of the outer periphery 4 of the vacuum heat insulating material 1 is 4.9 × 10 ⁻¹⁵ mol / m ² / s / Pa.

  Moreover, in the sealing part 8, generation | occurrence | production of the crack was not confirmed in the aluminum foil.

(Example 3)
In the first embodiment, a linear low density polyethylene film having a thickness of 50 μm is used as the heat welding layer 7, an aluminum foil having a thickness of 6 μm is used as the gas barrier layer 6, and two nylon films having a thickness of 15 μm and 25 μm are used as the surface protective layer 5. A vacuum heat insulating material 1 composed of a laminated jacket material 4, a core material 2 made of glass fiber, and an adsorbent 3 formed by enclosing calcium oxide in a ventilation wrapping material was produced.

  On the peripheral side (outer peripheral portion) of the jacket material 4, there is a sealing portion 8 in which the heat-welding layers 7 of the jacket material 4 are fused and bonded together, and the two melted surfaces located in the sealing portion 8 An uneven pattern 9 is formed on one of the outer cover material surfaces.

  The concavo-convex pattern 9 is formed by a difference in thickness of the heat-welded layer 7 where the concavo-convex pattern 9 is located, and the thickness of the heat-welded layer 7 located in the recess 10 is thinner than the heat-welded layer 7 located in the periphery thereof. It has become.

  It is assumed that the width of the sealing portion 8 of the vacuum heat insulating material 1 is 20 mm, and the uneven pattern 9 is formed over the entire inner portion by 1 mm from the outer peripheral side and the inner peripheral side of the sealing portion 8.

  The concave / convex pattern 9 is a pattern as shown in FIG. 3, and the concave portions 10 are all surrounded by the convex portions 12.

  Furthermore, it is assumed that the shape of the concave portion 10 on the surface of the jacket material 4 is a right isosceles triangle having a side of 6.75 mm, and the width of the convex portion 12 is 1.5 mm.

  Of the boundary surface between the heat-welded layer 7 and the gas barrier layer 6, the radius of curvature of the arc located at the boundary portion between the concave portion 10 and the convex portion 12 formed by the boundary surface having a large wave height is 1.5 mm. Each wave height of the waviness of the boundary surface was 0.2 mm. The maximum wave height of the other boundary surface was 0.05 mm.

At this time, when the thickness of the thin wall portion 11 is 15 μm, the amount of atmospheric gas entering through the sealing portion 8 from the end surface of the outer periphery of the outer cover material 4 of the vacuum heat insulating material 1 is 2.3 × 10 ⁻¹⁵ mol / m ² / s / Pa.

  Moreover, in the sealing part 8, generation | occurrence | production of the crack was not confirmed in the aluminum foil.

Example 4
In the first embodiment, a linear low density polyethylene film having a thickness of 50 μm is used as the heat welding layer 7, an aluminum foil having a thickness of 6 μm is used as the gas barrier layer 6, and two nylon films having a thickness of 15 μm and 25 μm are used as the surface protective layer 5. A vacuum heat insulating material 1 composed of a laminated jacket material 4, a core material 2 made of glass fiber, and an adsorbent 3 formed by enclosing calcium oxide in a ventilation wrapping material was produced.

  On the peripheral side (outer peripheral portion) of the jacket material 4, there is a sealing portion 8 in which the heat-welding layers 7 of the jacket material 4 are fused and bonded together, and the two melted surfaces located in the sealing portion 8 An uneven pattern 9 is formed on one of the outer cover material surfaces.

  The concavo-convex pattern 9 is formed by a difference in thickness of the heat-welded layer 7 where the concavo-convex pattern 9 is located, and the thickness of the heat-welded layer 7 located in the recess 10 is thinner than the heat-welded layer 7 located in the periphery thereof. It has become.

  It is assumed that the width of the sealing portion 8 of the vacuum heat insulating material 1 is 20 mm, and the uneven pattern 9 is formed over the entire inner portion by 1 mm from the outer peripheral side and the inner peripheral side of the sealing portion 8.

  The concave / convex pattern 9 is a pattern as shown in FIG. 3, and the concave portions 10 are all surrounded by the convex portions 12.

  Furthermore, it is assumed that the shape of the concave portion 10 on the surface of the jacket material 4 is a right isosceles triangle having a side of 6.75 mm, and the width of the convex portion 12 is 1.5 mm.

  Of the boundary surface between the heat-welded layer 7 and the gas barrier layer 6, the radius of curvature of the arc located at the boundary portion between the concave portion 10 and the convex portion 12 formed by the boundary surface where the wave height of the undulation is large is 1.1 mm. Each wave height of the waviness of the boundary surface was 0.18 mm. The maximum wave height of the other boundary surface was 0.05 mm.

At this time, when the thickness of the thin portion 11 is 15 μm, the amount of atmospheric gas entering through the sealing portion 8 from the end surface of the outer periphery 4 of the vacuum heat insulating material 1 is 3.6 × 10 ⁻¹⁵ mol / m ² / s / Pa.

  Moreover, in the sealing part 8, generation | occurrence | production of the crack was not confirmed in the aluminum foil.

(Comparative Example 1)
An outer sheath formed by laminating a linear low-density polyethylene film having a thickness of 50 μm as the heat welding layer 7, an aluminum foil having a thickness of 6 μm as the gas barrier layer 6, and two nylon films having a thickness of 15 μm and 25 μm as the surface protective layer 5. A vacuum heat insulating material composed of a material 4, a core material 2 made of glass fiber, and an adsorbent 3 formed by enclosing calcium oxide in a ventilation wrapping material was produced.

When the thickness of the heat-welding layer 7 in the sealing part 8 is substantially uniform 100 μm, the amount of atmospheric gas entering through the sealing part 8 from the end surface of the outer periphery 4 of the vacuum heat insulating material 1 is 2.0 ×. It was 10 ⁻¹⁴ mol / m ² / s / Pa.

  Moreover, in the sealing part 8, generation | occurrence | production of the crack was not confirmed in the aluminum foil.

(Comparative Example 2)
An outer sheath formed by laminating a linear low-density polyethylene film having a thickness of 50 μm as the heat welding layer 7, an aluminum foil having a thickness of 6 μm as the gas barrier layer 6, and two nylon films having a thickness of 15 μm and 25 μm as the surface protective layer 5. The vacuum heat insulating material 1 comprised from the material 4, the core material 2 which consists of glass fiber, and the adsorbent 3 which encloses calcium oxide in a ventilation packaging material was produced.

  On the peripheral side (outer peripheral portion) of the jacket material 4, there is a sealing portion 8 in which the heat-welding layers 7 of the jacket material 4 are fused and bonded together, and the two melted surfaces located in the sealing portion 8 An uneven pattern 9 is formed on one of the outer cover material surfaces.

  The concavo-convex pattern 9 is formed by a difference in thickness of the heat-welded layer 7 where the concavo-convex pattern 9 is located, and the thickness of the heat-welded layer 7 located in the recess 10 is thinner than the heat-welded layer 7 located in the periphery thereof. It has become.

  As shown in FIG. 8, the recess 10 is formed in a groove shape parallel to the periphery of the outer covering material 4 on the four sides so as to reach the end of the vacuum heat insulating material 1. The width of the recess 10 is 8.0 mm, Each part has a width of 1.5 mm.

  Of the boundary surface between the heat-welded layer 7 and the gas barrier layer 6, the radius of curvature of the arc located at the boundary portion between the concave portion 10 and the convex portion 12 formed by the boundary surface having a large wave height is 1.5 mm. Each wave height of the waviness of the boundary surface was 0.2 mm. The maximum wave height of the other boundary surface was 0.05 mm.

When the width of the sealing portion 8 of the vacuum heat insulating material 1 is 20 mm and the thickness of the thin portion 11 is 15 μm, the amount of atmospheric gas that enters through the sealing portion 8 from the end surface of the outer periphery of the outer cover material 4 of the vacuum heat insulating material 1 is As a trial calculation, it was 6.9 × 10 ⁻¹⁵ mol / m ² / s / Pa.

  However, generation | occurrence | production of the crack was confirmed in the aluminum foil in the recessed part 10 position.

(Comparative Example 3)
An outer sheath formed by laminating a linear low-density polyethylene film having a thickness of 50 μm as the heat welding layer 7, an aluminum foil having a thickness of 6 μm as the gas barrier layer 6, and two nylon films having a thickness of 15 μm and 25 μm as the surface protective layer 5. The vacuum heat insulating material 1 comprised from the material 4, the core material 2 which consists of glass fiber, and the adsorbent 3 which encloses calcium oxide in the ventilation | gas_flowing packaging material was produced.

  On the peripheral side (outer peripheral portion) of the jacket material 4, there is a sealing portion 8 in which the heat-welding layers 7 of the jacket material 4 are fused and bonded together, and the two melted surfaces located in the sealing portion 8 An uneven pattern 9 is formed on one of the outer cover material surfaces.

  The concavo-convex pattern 9 is formed by a difference in thickness of the heat-welded layer 7 where the concavo-convex pattern 9 is located, and the thickness of the heat-welded layer 7 located in the recess 10 is thinner than the heat-welded layer 7 located in the periphery thereof. It has become.

As shown in FIG. 9, two recesses 10 are arranged in a direction perpendicular to the periphery of the outer cover material 4 on the four sides, and end portions of the vacuum heat insulating material 1 in a groove shape parallel to the outer periphery of the cover material 4. The width of the concave portion 10 is 3.0 mm, and the width of the convex portion is 1.5 mm.
Four of the four sides of the sealing portion 8 are formed with a groove-like thin portion 9 parallel to the peripheral edge arranged in four directions perpendicular to the peripheral edge,
Of the boundary surface between the heat-welded layer 7 and the gas barrier layer 6, the radius of curvature of the arc located at the boundary portion between the concave portion 10 and the convex portion 12 formed by the boundary surface having a large wave height is 1.5 mm. Each wave height of the waviness of the boundary surface was 0.2 mm. The maximum wave height of the other boundary surface was 0.05 mm.

When the width of the sealing part 8 of the vacuum heat insulating material 1 is 20 mm and the thickness of the thin part 11 is 30 μm, the amount of atmospheric gas that enters through the sealing part 8 from the end surface of the outer periphery of the outer cover material 4 of the vacuum heat insulating material 1 is As a trial calculation, it was 3.6 × 10 ⁻¹⁵ mol / m ² / s / Pa.

  However, generation | occurrence | production of the crack was confirmed in the aluminum foil in the recessed part 10 position.

  As mentioned above, the Example and the comparative example in this invention are shown in (Table 1).

ただし、（表１）における外被材４の劣化に関しては、下記の基準で判定した。

However, the deterioration of the jacket material 4 in (Table 1) was determined according to the following criteria.

  ○: No deterioration (after a predetermined handling operation was performed on 10 vacuum heat insulating material samples, no increase in pinholes was confirmed in the aluminum foil located in the recess).

  X: Deteriorated (after a predetermined handling operation was performed on 10 vacuum heat insulating material samples, an increase in pinholes was confirmed in the aluminum foil located in the recess).

  From the results of (Table 1), the vacuum heat insulating material 1 shown in the first embodiment has a difference in effect depending on the configuration of the concavo-convex pattern 9 and the thickness of the thin wall portion 11, but the vacuum heat insulating material 1 in which the thin wall portion 11 is not provided. There was always a significant difference in the amount of gas intrusion. Further, no deterioration was seen in the jacket material 4.

  The vacuum heat insulating material according to the present invention has a heat insulating performance that can withstand long-term use, such as a refrigerator heat insulating material, a vending machine, a building heat insulating material, an automotive heat insulating material, a cold insulation box, and the like. It can also be applied to.

DESCRIPTION OF SYMBOLS 1 Vacuum heat insulating material 2 Core material 4 Cover material 6 Gas barrier layer 7 Heat welding layer 8 Sealing part 9 Concave-convex pattern 10 Concave part 11 Thin part 12 Convex part

Claims (8)

In a vacuum heat insulating material in which a core material is sealed under reduced pressure between two outer cover materials facing each other with a thermal welding layer, and outer peripheral portions in the vicinity of the peripheral edges of the two outer cover materials covering the core material are heat-welded. The concavo-convex pattern on the surface of one outer jacket material located at the sealing portion where the outer peripheral portions of the outer jacket material are heat-welded is on the convex portion if the cross-section of the sealing portion passes through a point on the concave portion. The vacuum heat insulating material is characterized in that a thin-walled portion is formed in the recess so that the thickness of the heat-welded layer is thinner than the peripheral portion of the recess. The vacuum heat insulating material according to claim 1, wherein the concavo-convex pattern has the concave portion surrounded by the convex portion. The vacuum heat insulation according to claim 1 or 2, wherein the sealing portion has at least two thin-walled portions in a cross section perpendicular to the outer periphery of the jacket material of the sealing portion passing through a point on the concave portion. Wood. The vacuum heat insulating material according to any one of claims 1 to 3, wherein the uneven pattern is a lattice pattern. The vacuum heat insulating material according to any one of claims 1 to 4, wherein the concave portion of the concavo-convex pattern is surrounded by the convex portion. The vacuum heat insulating material according to any one of claims 1 to 5, wherein a thickness change of the thermal welding layer located at a boundary portion between the adjacent concave portion and the convex portion is substantially arcuate. The heat-sealed layer of the sealing portion has a boundary surface with another layer on both surfaces, and the wave height of the undulation of one of the boundary surfaces of the sealing portion where the uneven pattern is formed is The vacuum heat insulating material according to any one of claims 1 to 6, wherein the vacuum heat insulating material is larger than a wave height of the undulation of the boundary surface. The thickness of a part of the heat welding layer located in the convex part formed between the adjacent concave parts formed in the continuous sealing part has two or more non-sealed parts of the jacket material. The vacuum heat insulating material as described in any one of Claim 1 to 7 which is thicker than the sum total of the thickness of the said heat welding layer which has.

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