JP5627773B2 - Vacuum heat insulating material and heat insulating box using the same - Google Patents

Description

  The present invention relates to a vacuum heat insulating material and a heat insulating box using the same, such as a refrigerator.

  Conventionally, urethane foam has been used as a heat insulating material used in a heat insulating box such as a refrigerator. However, in recent years, due to market demands for energy saving and small space and large capacity, a form in which a vacuum heat insulating material having better heat insulating performance than urethane foam is embedded in urethane foam and used together has become mainstream. Such a vacuum heat insulating material is used not only for a refrigerator but also for a heat insulating box of a cooling device such as a heat storage, a vehicle air conditioner, and a water heater.

The vacuum heat insulating material is configured by inserting powder, foam, fiber, etc. as a core material in an outer packaging material made of a plastic laminate film using an aluminum foil or the like for the gas barrier layer. A vacuum of several Pa (Pascal) or less is maintained.
Furthermore, an adsorbent that adsorbs gas and moisture is disposed in the outer packaging material in order to suppress the deterioration of the degree of vacuum, which is a cause of lowering the heat insulating performance of the vacuum heat insulating material.

  As the core material of such a vacuum heat insulating material, powders such as silica, foams such as urethane, and fiber bodies are used, but at present, inorganic fibers such as glass fibers and ceramic fibers that are excellent in heat insulating performance are mainly used. (For example, refer to Patent Document 1 and Patent Document 8).

  However, glass fiber may be irritated when dust scatters and adheres to the skin, mucous membrane, etc. of an operator during the manufacture of a vacuum heat insulating material, and its handling and workability are problematic.

  Also, when considering the scene of recycling, for example, in a refrigerator, each product is pulverized in a recycling factory, and glass fiber is mixed with urethane scraps and used for thermal recycling. There is a drawback that recyclability is not good.

  Therefore, organic fibers such as polypropylene fiber, polylactic acid fiber, aramid fiber, LCP (liquid crystal polymer) fiber, polyethylene terephthalate fiber, polyester fiber, polyethylene fiber, cellulose fiber, and polystyrene fiber are used as the core material other than glass fiber. (For example, refer to Patent Document 2 and Patent Document 7).

And in order to improve the heat insulation performance, those using these fibers have a fibrous shape, such as cotton, laminated sheets (for example, see Patent Document 3 and Patent Document 4), and sheets as fibers. There is a laminate in which the orientations are alternated (see, for example, Patent Document 5 and Patent Document 6).
Thereby, the heat conductivity of the vacuum heat insulating material which used the fiber as the core material is about 0.002 [W / mK].

  However, in such a vacuum heat insulating material having an organic fiber such as polyester as a core material, the organic fiber is a valuable resource when a product such as a refrigerator incorporating the same is dismantled by equipment of a recycling center. Tangled with iron scraps. This is because the current crushing equipment for refrigerator insulation boxes at recycling centers is designed and manufactured on the assumption of conventional insulation boxes made only of urethane insulation, so the length of resins such as tough and flexible resins is long. The fiber nonwoven fabric is caused by the fact that crushing may be insufficient. For this reason, the quality of the recovered product is lowered.

  The problem of quality degradation of recovered products due to entanglement of such valuables as organic fibers is the use of a core material that is easy to break by inserting a slit-shaped processed part from the surface layer part to the inside. (See, for example, Patent Documents 9 and 10).

JP-A-8-028776 (page 2-3) JP 2002-188791 A (page 4-6, FIG. 1) Japanese Patent Laying-Open No. 2005-344832 (page 3-4, FIG. 1) Japanese Patent Laying-Open No. 2006-307921 (page 5-6, FIG. 2) JP 2006-017151 A (page 3, FIG. 1) Japanese Examined Patent Publication No. 7-103955 (2nd page, Fig. 3-4) JP 2006-283817 A (page 4-5) Japanese Patent Laying-Open No. 2005-344870 (page 7, FIG. 2) JP 2000-283634 (Abstract, FIG. 1) Japanese Utility Model Publication No. 62-156793 (FIG. 1)

  However, in the vacuum heat insulating material using the core material into which the slit-shaped processed part is inserted from the surface layer portion toward the inside, the breakability is increased, but the strength is extremely lowered, and the core material is easily separated. The productivity of vacuum insulation is also inferior.

  This invention was made | formed in order to solve said subject, and makes it the 1st objective to improve the crushability at the time of the recycling of the product with a vacuum heat insulating material applied. In addition, the vacuum heat insulating material core material is difficult to get entangled with valuable scraps of iron, etc., which can improve recyclability, and at the time of production, the core material is difficult to disperse and the productivity can be improved. An object of the present invention is to provide a heat insulating material and a heat insulating box using the heat insulating material.

The present invention is a vacuum heat insulating material in which a core material in which sheet-like fiber assemblies are laminated is enclosed in a gas barrier outer packaging material, and the inside is decompressed,
The sheet-like fiber assembly is perforated.

  Moreover, the heat insulation box which concerns on this invention arrange | positions said vacuum heat insulating material between an outer box and an inner box.

  According to the present invention, since the fiber assembly constituting the core material is perforated, a vacuum that can improve handling at the time of manufacture and crushability at the home appliance recycling center without impairing the heat insulating performance. A heat insulating material and a heat insulating box using the heat insulating material can be obtained.

It is a perspective view of the vacuum heat insulating material which concerns on Embodiment 1 of this invention. FIG. 2 is an exploded perspective view of FIG. 1. It is detail drawing of the core material of FIG. It is an enlarged plan view of the sheet-like single long-fiber nonwoven fabric which comprises the core material of FIG. 3, and its AA sectional drawing. It is a top view which shows the sheet-like fiber assembly which comprises the core material for demonstrating the specification example 1 of the perforation process of FIG. It is a graph which shows the relationship between the length of the non-processed part in the perforation of the sheet-like fiber assembly which comprises a core material, and elongation rate. It is a graph which shows the relationship between the length of the slit-shaped process part in the perforation of the sheet-like fiber assembly which comprises a core material, and elongation rate. It is a top view which shows the sheet-like fiber assembly which comprises the core material for demonstrating the specification example 2 of the perforation process of FIG. It is a graph which shows the relationship between the space | interval between perforations of a sheet-like fiber assembly which comprises a core material, and elongation rate. It is a top view which shows the sheet-like fiber assembly which comprises the core material for demonstrating the specification example 3 of the perforation process of FIG. It is explanatory drawing of the specification example 4 of the perforation process of FIG. It is explanatory drawing of the specification example 5 of the perforation process of FIG. It is explanatory drawing of the specification example 6 of the perforation process of FIG. It is process drawing which shows the lamination | stacking method of a nonwoven fabric, and the manufacturing method of a core material. It is typical explanatory drawing of the heat insulation box which concerns on Embodiment 2 of this invention.

[Embodiment 1]
In FIG. 1 and FIG. 2 for explaining the vacuum heat insulating material according to Embodiment 1 of the present invention, the vacuum heat insulating material 1 is a bag-shaped gas barrier container 2 (hereinafter referred to as an outer packaging material) having air barrier properties, It consists of a core material 3 and an adsorbent 4 enclosed in the outer packaging material 2. The adsorbent 4 is a moisture adsorbent or a gas adsorbent, and adsorbs moisture in the outer packaging material 2 that causes a decrease in heat insulation performance.

  Out of the four sides of the outer packaging material 2, three sides other than the opening 2a are closed in advance by heat sealing, and the core material 3 is inserted into the outer packaging material 2 from the opening 2a as indicated by an arrow a, and the outer packaging material After the inside of the outer packaging material 2 is depressurized to a predetermined degree of vacuum with the core material 3 enclosed in 2, the vacuum heat insulating material 1 is manufactured by closing the opening 2a by heat sealing.

  FIG. 3 is a perspective view showing details of the core material 3. The core material 3 is composed of a laminated body 5 and is obtained by continuously winding several hundreds of long fiber nonwoven fabrics 6 that are sheet-like fiber assemblies from the inner side toward the outer side as indicated by an arrow b. The substantially cylindrical laminated body 5 is pulled and folded in the winding direction and crushed up and down.

Therefore, this laminated body 5 is a bent portion obtained by bending a portion connecting the upper surface side flat plate portion 5a and the lower surface side flat plate portion 5b with the upper surface side flat plate portion 5a and the lower surface side flat plate portion 5b which are flat when folded. That is, the laminated body 5 is formed into a single flat plate formed by the bent portions 5c and 5d serving as end portions in the winding direction.
By using this laminated body 5 as the core material 3, one flat vacuum heat insulating material 1 having a substantially uniform thickness is manufactured. In FIG. 3, an arrow a indicates the insertion direction of the core material 3 into the outer packaging material 2.

FIG. 4 is an enlarged plan view of a single sheet-like long-fiber nonwoven fabric 6 constituting the laminated body 5 of FIG.
The long-fiber non-woven fabric 6 is composed of a large number of fibers 7. However, since the large number of fibers 7 are not connected to each other as they are, they are broken apart just by being lifted and cannot constitute a sheet. .

  In order to prevent this, after a large number of fibers 7 are formed into a sheet (this is referred to as a web), the fibers 7 are welded together by hot embossing to form a long-fiber nonwoven fabric 6 in which the fibers are not scattered. Yes. Reference numeral 8 denotes a hot embossed portion where the fibers 7 are welded by hot embossing, and the region other than the hot embossed portion 8 is in the state of the fiber 7. By adjusting the ratio of the heat embossed portion 8 to the entire sheet, it can be handled as a sheet without impairing the heat insulating performance of the fiber 7.

  Thereby, although the handleability at the time of manufacture of the vacuum heat insulating material 1 improved significantly, since the crushability in a recycling center will deteriorate as mentioned above, the perforation process part which gave the perforation 9 is provided. This suppresses the elongation of the long-fiber nonwoven fabric 6 at the time of crushing, and achieves both improved handling and crushability. In addition, in this invention, in order to suppress the elongation of the long-fiber nonwoven fabric 6 at the time of crushing in a recycling center and to improve handling property and crushability, the long-fiber nonwoven fabric 6 is used as described later (FIGS. Description), slit-shaped processed part (hereinafter, sometimes simply referred to as “processed part”) 9a and non-processed part 9b alternately processed part of perforation 9, or half not completely cut in the thickness direction In the following description, these are collectively referred to as a perforated portion or a perforated portion as described above. That is, the slit-shaped processed part includes a completely cut processed part or a half-cut half cut part.

<Fiber material>
Resin fibers are used for the fibers constituting the core material 3 of the vacuum heat insulating material 1, and polyester fibers, polypropylene fibers, polystyrene (hereinafter referred to as PS) fibers, polylactic acid fibers, aramid fibers, and liquid crystal polymers (hereinafter referred to as LCPs). ) Fiber, polyphenylene sulfide (hereinafter referred to as PPS) fiber, and the like.

  If heat-resistant fibers such as LCP fiber and PPS fiber are used, the heat resistance of the core material 3 can be improved. If fibers having a large diameter are used, the compression creep characteristics of the core material 3 are improved. be able to. Furthermore, when it is desired to obtain both characteristics, a vacuum heat insulating material 1 having excellent compression creep characteristics, high heat resistance, and high heat insulation can be obtained by mixing heat-resistant fibers and large-diameter fibers. It is done.

  By the way, since PS fiber has low solid thermal conductivity and can be expected to improve heat insulation performance as a heat insulating material and can be manufactured at low cost, in the following description, the core material 3 of the vacuum heat insulating material 1 is made of the material itself. An example of using PS fibers that are small in elongation and advantageous for friability at a recycling center will be described.

<Manufacture of long-fiber nonwoven fabric>
Next, a process until PS fiber is obtained by heat-melt spinning PS resin to obtain a sheet-like long fiber nonwoven fabric will be described.
First, PS resin pellets are conveyed to an extruder. The PS resin heated, kneaded and melted at 270 to 310 ° C in an extruder passes through a polymer filter for removing foreign substances, and then continuously from a nozzle having a large number of holes having a diameter of 0.2 to 0.6 mm by a gear pump. Pushed out.

The extruded PS resin is drawn with compressed air at a yarn speed of 2000 m / min to 6000 m / min while being cooled with cold air, and is collected on a mesh conveyor as continuous fibers having a desired fiber diameter.
In the present embodiment, a nozzle having about 4000 holes with a diameter of 0.4 mm was used, and spinning was performed at a yarn speed of 3800 m / min to obtain a fiber diameter of about 13 μm. In addition, the measurement of an average fiber diameter measures several places-several hundred places (for example, 10 places) using a microscope, and uses the average value.

  The fiber 7 heated and melt-spun from the PS resin pellets and collected on the mesh conveyor as described above is collected as a fiber web that is a lump of fibers. However, in the state of the fiber web, the fibers 7 are separated as they are, and are difficult to handle as the core material 3 in the operation of being accommodated in the outer packaging material 2.

  Therefore, in order to prevent the fibers from being scattered, after pressing with a roller heated to 40 to 120 ° C., heat embossing is performed with a heating roller of 40 to 120 ° C., and the fibers are thermally welded. Such a long fiber nonwoven fabric 6 is processed. In FIG. 4, the concave portion is the hot embossed portion 8 subjected to the hot embossing, but the fibers 7 are heated and pressure welded with a minimum area to prevent the fibers 7 from being separated.

In the present embodiment, the hot embossed portion 8 has a substantially circular shape with a diameter of about 0.5 to 1 mm, is provided at intervals of about 1 to 3 mm, and the ratio of the hot embossed portion 8 in the sheet is about 6%. Thus, by setting the ratio of the heat embossed portion 8 in the sheet to about 6%, the heat insulation performance is not impaired as compared with the conventional resin fiber cotton-like core material using the same material. It is possible to obtain the long-fiber nonwoven fabric 6 that is securely welded and has a strength that does not break even when stress is applied in the subsequent core material manufacturing process (fiber assembly laminating process). In general, the thickness of the nonwoven fabric represented by the weight per unit area (fiber weight per 1 m ² (g)) can be adjusted by the speed of the conveyor. The long fiber nonwoven fabric 6 subjected to the heat embossing in this way is wound up in a roll shape to obtain an original fabric roll.

<Perforation to be provided in long fiber nonwoven fabric>
Next, specification examples of perforations provided in the long fiber nonwoven fabric 6 (hereinafter simply referred to as nonwoven fabric) will be described with reference to FIGS.
Specification example 1.
FIG. 5 is a plan view showing a sheet-like fiber assembly constituting a core material for explaining the specification example 1 of the perforation processing of FIG. As shown in FIGS. 1 to 4, the core material 3 according to the specification example 1 includes a laminated body 5 in which a plurality of sheet-like fiber assemblies 3 a are laminated. Further, the core material 3 is formed with a single perforation 9 in each of the sheet-like fiber assemblies 3a in which every other non-processed part 9b and slit-like processed part 9a penetrating the sheet are continuous. Yes. That is, the perforation 9 is formed from one end of the longitudinal direction to the other end along the center line extending in the longitudinal direction of the sheet-like fiber assembly 3a. In the perforation 9, the length of the non-processed portion 9b is set in the range of 1 to 5 [mm], and the length of the slit-shaped processed portion 9a is set to 3 [mm] or more. These values are determined based on the characteristics of the sheet-like fiber assembly 3a obtained as a result of the following experiments by the present inventors.

The experiment was performed by forming perforations with a cutter on a polyester sheet-like organic fiber assembly having a basis weight of 18 [g / m ² ] as the core material 3. In addition, although implemented with the polyester fiber here, other than that, for example, polystyrene fiber, polypropylene fiber, polylactic acid fiber, aramid fiber, LCP (liquid crystal polymer) fiber, polyethylene fiber, and cellulose fiber may be used.

  The problem is entanglement with iron scraps, etc., but this is considered to be caused by the high elongation rate. Therefore, we focused on the growth rate.

  First, a sample was prepared by fixing the length of the slit-shaped processed part 9a to 4 [mm] and changing the length of the non-processed part 9b. The sample size is 25 [mm] wide and 100 [mm] long. Using a tensile tester, both ends in the length direction of the sample were sandwiched between chucks, pulled in the length direction, and measured for elongation. The distance between chucks is 15 [mm] at a pulling speed of 50 [mm / min]. Here, the elongation percentage is obtained by dividing the elongation at the time of breaking the sample (nonwoven fabric) by the distance between chucks. The measurement results are shown in FIG.

  FIG. 6 is a graph showing the relationship between the length of the non-processed portion and the elongation at the perforation of the sheet-like fiber assembly constituting the core material, with the horizontal axis representing the length of the non-processed portion and the vertical axis representing the elongation. It is a thing. As is apparent from FIG. 6, the elongation rate decreases as the length of the non-processed portion 9b decreases. In particular, when the elongation value when the length of the non-processed portion 9b is 6 to 8 [mm] is compared with the elongation value when the length is 3 to 5 [mm], the length of the non-processed portion 9b is It can be seen that the value of the elongation at 5 [mm] or less is greatly reduced. However, if the length of the non-processed portion 9b is less than 1 [mm], the perforation 9 is likely to be cut and the handleability is deteriorated. From the above, the length of the non-processed portion 9b is appropriately 1 to 5 [mm].

  Next, the length of the non-processed part 9b was fixed to 2 [mm], and the elongation rate was measured by changing the length of the slit-shaped process part 9a. The measurement results are shown in FIG.

  FIG. 7 is a graph showing the relationship between the length of the slit-like processed part and the elongation at the perforation of the sheet-like fiber assembly constituting the core material, the horizontal axis is the length of the slit-like processed part, and the vertical axis is It is the rate of growth. As is apparent from FIG. 7, the elongation rate decreases as the length of the slit-like processed portion 9a increases. In particular, when the length of the slit-shaped processed portion 9a is 1 to 2 [mm] and the value of the elongation when the slit is cut by 3 [mm] or more are compared, the slit-shaped processing It can be seen that the elongation value when the length of the portion 9a is cut by 3 [mm] or more is greatly reduced. Therefore, the length of the slit-shaped processed part 9a is suitably 3 [mm] or more.

  Next, a sheet-like organic fiber assembly 3a having a perforation 9 in which the length of the non-processed portion 9b is 5 [mm] and the length of the slit-shaped processed portion 9a is 3 [mm] is used as a core material 3 It put in the material 2, it was made to dry at 100 degreeC, adsorbent was put, and vacuum packing was performed at several Pa, and the vacuum heat insulating material 1 was produced. When the heat insulating performance was measured, the thermal conductivity was 0.0023 [W / mK], which is the same as that without perforations. That is, it was found that the friability can be improved while maintaining the heat insulation performance. As a result, the core material 3 can be made difficult to separate during production, and can be easily crushed during recycling. As a result, the core material 3 is less likely to be entangled with iron scraps during recycling, and the purity of the iron scraps can be improved. And the recycling rate was able to be improved because purity, such as iron scrap, went up.

Specification example 2
FIG. 8 is a plan view showing a sheet-like fiber assembly constituting the core material for explaining the specification example 2 of the perforation processing of FIG. 4, and parts corresponding to the specification example 1 are given the same reference numerals. It is. In the description, reference is made to FIGS. The core material 3 according to the specification example 2 is formed by arranging a plurality of perforations 9 in one direction in the sheet-like fiber assembly 3a as shown in FIG. 6 [mm] or less. Other configurations are the same as those of the first embodiment.

  In the core material 3 according to the specification example 2, a plurality of lines of perforations 9 are arranged in one direction on the sheet-like fiber assembly 3a, and an interval 9c between the perforations 9 is set to 6 [mm] or less. However, this value is also determined based on the characteristics of the sheet-like fiber assembly 3a obtained as a result of experiments by the present inventors.

  That is, the same sample as used in the first embodiment (however, here, a nonwoven fabric in which a plurality of perforations are arranged in one direction) and a tensile tester are used, and the interval 9c between the perforations 9 is changed. The elongation was measured. The measurement results are shown in FIG.

  FIG. 9 is a graph showing the relationship between the spacing between the perforations and the elongation rate of the sheet-like fiber assembly, with the horizontal axis representing the spacing between the perforations and the vertical axis representing the elongation rate. As is clear from FIG. 9, the shorter the interval 9c between the perforations 9, the lower the elongation rate. However, when the interval 9c between the perforations becomes 6 [mm] or less, no significant change is observed in the decrease in the elongation rate. . Therefore, it was found that the interval 9c between the perforations is 6 [mm] or less. That is, it was found that the friability can be improved while maintaining the heat insulation performance.

Specification example 3.
FIG. 10 is a plan view showing a sheet-like fiber assembly constituting the core material for explaining the specification example 3 of the perforation processing of FIG. 4, and parts corresponding to the specification example 1 described above are denoted by the same reference numerals. It is. In the description, reference is made to FIGS. The core material 3 according to the specification example 3 is formed by arranging a plurality of perforations 9A and 9B in two directions (orthogonal directions) on the sheet-like fiber assembly 3a as shown in FIG. Other configurations are the same as those of the first embodiment.

  In the core material 3 according to the specification example 3, since the perforated lines 9A and 9B are arranged in parallel in two directions (orthogonal directions) on the sheet-like fiber assembly 3a, the elongation of the sheet-like fiber assembly 3a is increased. The rate can be further reduced, and crushing can be facilitated. That is, the friability can be further improved while maintaining the heat insulation performance.

Specification example 4
FIG. 11 is an explanatory view of a specification example 4 of the perforation processing of FIG. The core material 3 according to the specification example 4 is processed by completely cutting the perforation 9 in the sheet-like fiber assembly 3a as shown in FIG. 11 (cut through the nonwoven fabric 6 from the upper surface to the lower surface in the thickness direction). The portions 9a and the non-processed portions 9b are alternately continuous with a predetermined length, and are formed, for example, in the form of a dotted line and a lattice perforation.

Specification example 5
FIG. 12 is an explanatory diagram of a specification example 5 of the perforation processing of FIG. As shown in FIG. 12, the core material 3 according to the specification example 5 is formed in the sheet-like fiber assembly 3a only by the half-cut portion 9d that is a cut that does not penetrate the sheet-like fiber assembly 3a. For example, the non-processed portion 9b is eliminated and formed in a lattice shape by a continuous linear shape.

Specification example 6.
FIG. 13 is an explanatory diagram of a specification example 6 of the perforation processing of FIG. The core material 3 according to the specification example 6 is provided adjacent to the sheet-like fiber assembly 3a as shown in FIG. 13 with the cut portions 9a that are completely cut with respect to the production direction C of the nonwoven fabric 6 diagonally and in a staggered manner. A non-processed part 9b is formed between the processed parts 9a.

<Processing method of perforation to nonwoven fabric>
In processing the perforation to the nonwoven fabric 6, the raw fabric roll of the nonwoven fabric 6 once obtained was unwound, and after processing the perforation in the state of one nonwoven fabric, the method of winding on the roll again was taken. According to this method, since the multi-layer lamination is performed after the perforation processing is performed on the single nonwoven fabric 6, the perforation does not completely overlap, and the appearance of the vacuum heat insulating material 1 is not adversely affected. In addition, since the processing speed can be increased depending on the specification of the perforation and the cutting method (combination of die roll and slitter, etc.), in that case, the perforation processing step can be incorporated into the above-described nonwoven fabric manufacturing step.

  Further, after the non-woven fabric laminating step described later, the core material 3 on which the non-woven fabric 6 is laminated may be processed by perforation by pressing. In this case, since the perforation is performed after the nonwoven fabric 6 is laminated in the form of the core material 3, it is not necessary to consider the handling strength of each nonwoven fabric 6 in a later step, so that the crushability is better. Perforation can be performed.

<Nonwoven Fabric Lamination Method, Core Material Manufacturing Method>
Next, the lamination method of the nonwoven fabric 6 and the manufacturing method of the core material 3 are demonstrated.
FIG. 14 is an operation explanatory view of the raw roll 101 and the winding frame 111 constituting the laminating apparatus for the core material 3 of the vacuum heat insulating material 1, and shows the core material manufacturing process of the vacuum heat insulating material 1.

  FIG. 14A shows a winding start step of the nonwoven fabric 6 (hereinafter referred to as a fiber assembly). In the manufacturing process of the laminate 5, the continuous sheet-like fiber assembly 6 subjected to the heat embossing process is several times. A web roll 101 having a predetermined width formed by being wound and a winding frame 111 having a predetermined width for winding the fiber assembly 6 wound around the web roll 101 are provided. The fiber assembly 6 wound around the original fabric roll 101 is started to be wound around the winding frame 111.

  At this time, the end of the fiber assembly 6 pulled out from the raw fabric roll 101 is clamped by the clamp mechanism of the winding frame 111 so that the fiber assembly 6 is cut in the middle of winding or stretched to become narrow in width. It winds with the predetermined tension which there is nothing. In the figure, the original fabric roll 101 and the reel 111 are shown in contact with each other, but may be separated from each other.

  FIG. 14B is a winding end step of the fiber assembly 6. When the fiber assembly 6 wound around the winding frame 111 from the original fabric roll 101 in the winding start step is wound by the number of rotations corresponding to a predetermined thickness, the rotation of the original fabric roll 101 and the reel 111 is stopped. The winding of the assembly 6 is finished. The predetermined number of rotations wound around the winding frame 111, that is, the number of layers to be stacked, is arbitrarily set based on the thickness of the fiber assembly 6 at the time of decompression packing and the thickness of the vacuum heat insulating material 1 to be manufactured.

  FIG. 14C is a cutting step of the fiber assembly 6. The fiber assembly 6 is wound around the winding frame 111 by a predetermined number of rotations by the winding end step, and after the rotation of the original fabric roll 101 and the winding frame 111 is stopped, the fiber assembly 6 is moved to the original fabric roll 101 and the winding frame 111. At a predetermined cutting point between the two, the cutting is performed with the front and back clamped, and the original fabric roll 101 is separated from the reel 111.

  FIG. 14D shows a fixing step of the core material 3. After the fiber assembly 6 is cut by the cutting step, the clamp members 113a and 113b are inserted into the clamp member installation portions 112a and 112b provided on the winding frame 111, and the substantially cylindrical fiber assembly wound around the winding frame 111 is obtained. The body 6 is clamped.

  FIG. 14E shows a winding frame deformation step. After the fiber assembly 6 is clamped by the clamp members 113a and 113b by the fixing step of the core material 3, the circumferential member holding shafts 114a and 114b of the winding frame 111 are moved toward the center side so as to be contracted in the radial direction. The circumferential members 115a and 115b connected to the circumferential member holding shafts 114a and 114b are moved in the direction of contracting in the radial direction toward the center. In this way, the winding frame 111 is deformed, and the winding tension of the cylindrical fiber assembly 6 wound around the winding frame 111 is relaxed.

  FIG. 14F shows a winding frame separating step, in which the substantially cylindrical fiber assembly 6 whose tension has been loosened is extracted from the winding frame 111 in the axial direction of the rotating shaft 116.

  FIG. 14G shows a core material forming step. The substantially cylindrical fiber assembly 6 extracted from the winding frame 111 in a state of being clamped by the two clamp members 113a and 113b is pulled to the two clamp members 113a and 113b, respectively, on the opposite side to the substantially linear direction of the winding direction. As a result, the substantially cylindrical fiber assembly 6 is folded at the clamp positions of the clamp members 113a and 113b, so that the bent portions (folded portions) 5c and 5d in the winding direction, the upper surface side flat plate portion 5a, and the lower surface side flat plate portion. The laminated body 5 of the flat-plate-like (sheet-like) nonwoven fabric 6 having 5b, that is, the flat-plate-like (sheet-like) core material 3 is formed.

The core material 3 composed of the laminated body 5 formed in a flat plate shape is moved onto the conveyor with the bent portions 5c and 5d clamped by the clamp members 113a and 113b, and then the clamp members 113a and 113b are moved. By removing, the core material 3 as shown in FIG. 14 (h) is manufactured. Reference numeral 10 denotes a central portion of the substantially cylindrical fiber assembly 6 when the winding frame 111 is pulled out. The laminated body forming the upper surface side flat plate portion 5a and the laminated body forming the lower surface side flat plate portion 5b are separated. However, it is closed by removing the clamp members 113a and 113b.
By the above, it becomes the structure where the nonwoven fabric 6 was wound continuously toward the outer side from the inner side, and the laminated body 5 which was less scattered and excellent in handleability can be obtained.

<Procedure for manufacturing vacuum insulation material>
In manufacturing the vacuum heat insulating material 1, first, the core material 3 having a predetermined size and thickness produced by the core material manufacturing process is inserted into the bag-shaped outer packaging material 2 having the opening 2a, and the opening 2a is formed. It fixes so that it may not close, and it is dried for about 0.5 to 2 hours at 60-80 degreeC with a thermostat. Usually, a hot air circulation type drying furnace is used, but a drying furnace using dry air dehumidified in advance may be used.

  Since polystyrene (PS) according to this embodiment has low hygroscopicity, drying temperature and time can be set lower than materials having hygroscopicity such as polyethylene terephthalate. In order to absorb moisture remaining after drying, residual gas after vacuum packaging, outgas from the core material 3 released over time, permeated gas entering through the sealing layer of the outer packaging material 2, etc. An adsorbent 4 such as a gas adsorbent or a moisture adsorbent is inserted into 2 and evacuated (depressurized) by, for example, a Kashiwagi vacuum packaging machine. Vacuuming is performed until the degree of vacuum in the chamber reaches about 1 to 10 Pa, and the vacuum insulating material 1 is manufactured by heat-sealing the opening 2a of the outer packaging material 2 in the chamber as it is.

  In the present embodiment, the outer packaging material 2 of the vacuum heat insulating material 1 is a laminate film having a thickness of 5 μm to 100 μm, for example, nylon (thickness 15 μm), alumina-deposited PET (polyethylene terephthalate) (thickness 12 μm) Then, an aluminum-deposited EVOH (plastic laminate film having gully barrier properties composed of ethylene vinyl alcohol copolymer resin (thickness 15 μm) and polyethylene (thickness 50 μm) was used.

  The heat insulating property of the vacuum heat insulating material 1 thus obtained was evaluated by measuring the thermal conductivity with, for example, a thermal conductivity meter HC-074 manufactured by Eihiro Seiki Co., Ltd. In addition, the crushability can be reduced by introducing the heat insulation box of the refrigerator in which the obtained vacuum heat insulating material 1 is disposed in the heat insulation wall with urethane foam into the recycling process of the recycling center and mixing it into the metal recovery route. evaluated.

<Examples and comparative examples>
Next, the specification of the perforation in the Example (Examples 1-5) of the vacuum heat insulating material 1 which concerns on Embodiment 1 of this invention, and a comparative example (Comparative Examples 1-4) and its evaluation are demonstrated. In addition, perforation is performed over the full width and full length direction of the nonwoven fabric 6. FIG.
The evaluation results are shown in Table 1.

  The processed part 9a of the perforation 9 of the core material 3 of the vacuum heat insulating material 1 of Example 1 is based on the specification example 4 shown in FIG. 11, and the length of the processed part 9a is 3 mm and the length of the non-processed part 9b is. 1 mm, the processed part 9a is a complete cut with a cut through, and the processed part ratio of the perforation 9 (the ratio of the processed part 9a to the total length of the processed part 9a and the non-processed part 9b) is 75%. .

  The processed part 9a of the perforation 9 of the core material 3 of Example 2 has the same specifications as in Example 1, the processed part 9a is completely cut, its length is 4 mm, and the length of the non-processed part 9b is At 2 mm, the processed part ratio is 67%. The comparative example 1 has the same specifications, the length of the processed part 9a is 8 mm, the length of the non-processed part 9b is 2 mm, the processing ratio is 83%, and the comparative example 2 also has the same specification, the processed part 9a and the non-processed part. Each of the lengths of 9b is 3 mm, and the processing portion ratio is 50%.

In the core material 3 of Examples 1 and 2, the laminating workability in the laminating process and the crushability in the recycling center were good as shown in Table 1.
On the other hand, as shown in Table 1, the core material 3 of Comparative Example 1 had no problem with crushability, but the nonwoven fabric 6 was broken during lamination. This is presumably because the processed portion ratio was as large as 83% and the nonwoven fabric 6 could not withstand the winding tension.

In the case of Comparative Example 2, as shown in Table 1, there was no particular problem with respect to laminating workability, but for crushability, the ratio of the processed part was 50% and the ratio of the non-processed part 9b was too high. Becomes insufficient, the entanglement of the nonwoven fabric 6 to the crushed metal piece increases, the recovery to the urethane recovery process becomes insufficient, and the amount of mixing into the metal recovery process increases.
From the above, it can be said that the perforation processing portion ratio in the specification of FIG.

Next, the perforation 9 processed part 9a of the core material 3 of Example 3 is based on the specification of FIG. 12, and the half cut part 9d is formed in a continuous grid shape with a length of 30 mm, and the non-processed part 9b is eliminated. is there. The half-cut portion 9d withstands the lamination process of the nonwoven fabric 6 and is in a state where the fibers are crushed and hardened to such an extent that they can be shredded by impact during crushing.
In this embodiment, both lamination processability and crushability were good as shown in Table 1.

The perforated portion of Example 4 and Comparative Example 3 is according to the specifications of FIG. 12, and the size of the lattice is changed.
In Example 4, the half-cut portion 9d has a length of 50 mm, and in Comparative Example 3, the half-cut portion 9d has a length of 100 mm.
In the case of Example 4, both lamination processability and crushability were good as shown in Table 1. On the other hand, in the case of the comparative example 3, since the size of the nonwoven fabric 6 after crushing was too large, the amount of the nonwoven fabric 6 mixed into the metal recovery process increased. From this, it was found that the lattice size by perforation is preferably less than 100 mm ² . In addition, when forming the perforated portion with the half cut portion 9d, if the basis weight of the nonwoven fabric 6 is too small, the amount of fibers in the crushed portion is insufficient and it is difficult to cut from the half cut portion 9d at the time of crushing. The basis weight is preferably 26 g / m ² or more.

Example 5 is based on the specification of the perforation processing of FIG. 13, and the cuts of the completely cut processed portion 9 a are provided obliquely and staggered with respect to the manufacturing direction C of the nonwoven fabric 6.
In the present embodiment, the length L of the processed portion 9a is 6 mm, the clearance S ₁ (non-processed portion 9b) between the processed portion 9a and the processed portion 9a is 2 mm, and the longitudinal length of the former processed portion 9a is 2 mm. is provided with offset from the center, also the clearance S ₂ between the tip portion of the working portion 9a perpendicular and processing unit 9a and which was 2.8 mm.

  The lamination workability of the core material 3 in this embodiment is good as shown in Table 1, and the fibers of the nonwoven fabric 6 are strongly oriented in the production direction, so that the cut of the processed portion 9a is shifted. By doing so, the fiber can be divided, so that the elongation of the fiber during crushing can be suppressed, and the crushability is improved. In Comparative Example 4, the nonwoven fabric 6 is not provided with the perforation 9, and there is no problem in the laminating workability, but the crushability is remarkably inferior as described above.

[Embodiment 2]
FIG. 15 is an explanatory view of a heat insulation box according to Embodiment 2 of the present invention, schematically showing a refrigerator.
The refrigerator 20 includes an outer box 21 made of a coated steel plate and an inner box 22 made of a resin molded product installed inside the outer box 21 with a gap therebetween, and is formed between the outer box 21 and the inner box 22. A heat insulating wall 23 described later is provided in the gap. The inner box 22 is provided with a refrigeration unit (not shown) for supplying cold air, and the outer box 21 and the inner box 22 are respectively formed with openings on a common surface. The part is provided with an open / close door (both not shown).

  In the gap between the outer box 21 and the inner box 22 of the refrigerator 20, the vacuum heat insulating material 1 (shown exaggeratedly) according to the first embodiment is disposed and filled with polyurethane foam 25, and the heat insulating wall 23. Is supposed to form. However, since the outer packaging material 2 of the vacuum heat insulating material 1 includes an aluminum foil, there is a risk of generating a heat bridge between the outer box 21 and heat that passes through the aluminum foil.

  Therefore, in order to prevent the occurrence of such a heat bridge, the vacuum heat insulating material 1 is disposed away from the outer box 21 using a spacer 24 of a non-conductive resin molded product. In addition, the spacer 24 is appropriately provided with a hole for not inhibiting the flow so that a void does not remain in the polyurethane foam 25 injected into the gap between the outer box 21 and the inner box 22 in a later step.

  Thus, in the refrigerator 20 according to the present embodiment, the heat insulating wall 23 including the vacuum heat insulating material 1, the spacer 24, and the polyurethane foam 25 according to the first embodiment is formed between the outer box 21 and the inner box 22. Yes. The range in which the heat insulating wall 23 is provided is not limited, and may be the entire range of the gap formed between the outer box 21 and the inner box 22 or a part thereof. Further, it may be provided between the outer box 21 and the vacuum heat insulating material 1 and / or between the inner box 22 and the vacuum heat insulating material 1. Moreover, you may provide in the opening-and-closing door of an opening part.

  By the way, when the refrigerator is used, it is dismantled and recycled at recycling centers in various places based on the Home Appliance Recycling Law. At this time, since the refrigerator 20 according to the present invention has the vacuum heat insulating material 1 containing the core material 3 made of the fiber assembly 6, it can be crushed without removing the vacuum heat insulating material 1. Recyclability is good because there is no reduction in combustion efficiency or residue.

  In the above description, the case where the vacuum heat insulating material 1 according to the present invention is used in a refrigerator as an example of a heat insulating box is not limited to this. For example, a heat insulation box, a vehicle air conditioner, a water heater, etc. The vacuum heat insulating material 1 according to the present invention is also applied to a heat insulation bag (heat insulation container) including a deformable outer bag and an inner bag instead of a cooling device or a heating device, and further, a box having a predetermined shape. Can be used.

  DESCRIPTION OF SYMBOLS 1 Vacuum heat insulating material, 2 Outer packaging material, 2a Opening part, 3 Core material, 3a Sheet-like fiber assembly, 4 Adsorbent, 5 Laminated body, 6 Long fiber nonwoven fabric (fiber assembly), 7 Fiber, 8 Embossed part, 9, 9A, 9B Perforation, 9a Processed part, 9b Non-processed part, 9c Spacing between perforations, 9d Half cut part, 20 Refrigerator (heat insulation box), 21 Outer box, 22 Inner box, 23 Heat insulation wall, 24 Spacer , 25 Polyurethane foam, 101 raw fabric roll, 111 winding frame, 112a, 112b clamp member installation part, 113a, 113b clamp member, 114a, 114b circumferential member holding shaft, 115a, 115b circumferential member, 116 rotating shaft.

Claims (12)

A core composed of a laminate in which a plurality of sheet-like fiber assemblies are laminated;
An outer packaging material that envelops the core material and whose inside is decompressed;
The vacuum heat insulating material, wherein the core material is formed with perforations in which every other non-processed portion and slit-shaped processed portion are continuous in each of the sheet-like fiber assemblies.   2. The vacuum heat insulating material according to claim 1, wherein the slit-like processed portion is a completely cut processed portion or a half cut half cut portion.   The vacuum heat insulating material according to claim 1 or 2, wherein the perforations are formed in one direction or two directions.   4. The vacuum heat insulating material according to claim 3, wherein the perforation is formed by arranging a plurality of lines in the one direction or the two directions.   The vacuum heat insulating material according to claim 4, wherein the interval between the perforations arranged side by side is 6 mm or less.   The length of the non-processed portion of the perforation is 1 to 5 [mm], and the length of the slit-shaped processed portion is 3 [mm] or more. The vacuum heat insulating material according to claim 1.   The vacuum heat insulating material according to any one of claims 1 to 4, wherein a ratio of the processed portion to a total length of the processed portion and the non-processed portion of the perforation is 60 to 75%. .   The perforation is formed by processing parts arranged in a staggered manner inclined with respect to the manufacturing direction of the fiber assembly, and non-processed parts provided between the processing parts. The vacuum heat insulating material according to claim 1 or claim 2. A core composed of a laminate in which a plurality of sheet-like fiber assemblies are laminated;
An outer packaging material that envelops the core material and whose inside is decompressed;
In the core material, each of the sheet-like fiber aggregates has a lattice-like portion formed by a half-cut portion that is half-cut by a not-penetrated cut , and is surrounded by the half-cut portion. The vacuum heat insulating material characterized by having a size of less than 100 mm ² . Placement and outer box, and a box inner arranged inside the outer box, the vacuum heat insulating material according to any one of claims 1 to 9 between the inner box and the outer box Insulated box characterized by that. The heat insulating box according to claim 10 , wherein a heat insulating material is filled in both or either of the outer box and the vacuum heat insulating material and between the inner box and the vacuum heat insulating material. . The heat insulation according to claim 11 , wherein a spacer is provided between the outer box and the vacuum heat insulating material for positioning the vacuum heat insulating material and securing a flow path at the time of filling the heat insulating material. box.

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