Fire-resistant sheets and electronic equipment cases

Abstract

The present invention provides fire-resistant sheets and electronic equipment cases that do not require large-scale equipment, shorten the molding cycle, and reduce manufacturing costs and man-hours. [Solution] The fire-resistant sheet 1 according to this embodiment is housed in a battery case 2 of a lithium-ion battery, which is one embodiment of an electronic device case. Multiple plate-shaped laminates 11, 12, and 13, each made of a plurality of base materials and a thermosetting resin, are arranged in a continuous manner, with the laminates 11 and 13 overlapping with parts of other adjacent laminates 12 and 13.

Description

【Technical Field】 【0001】 The present invention relates to a refractory sheet used for a case of an electronic device and an electronic device case provided with the refractory sheet. 【Background Art】 【0002】 Conventionally, even when thermal runaway occurs in an electronic device housed inside a case of an electronic device such as a lithium-ion battery and ignition occurs, a refractory sheet (heat-resistant sheet) is provided in the case to suppress the spread of fire and the scattering of fragments. A technique is known (see, for example, Patent Document 1). 【Prior Art Documents】 【Patent Documents】 【0003】 【Patent Document 1】 Japanese Patent Application Laid-Open No. 2024-91065 【Summary of the Invention】 【Problems to be Solved by the Invention】 【0004】 The heat-resistant sheet described in the above patent document is formed by integral molding. When an integrally molded heat-resistant sheet is used for a large case, large equipment is required to mold the heat-resistant sheet. In addition, when the heat-resistant sheet is integrally molded, the molding cycle becomes long, resulting in problems such as an increase in manufacturing cost and man-hours. 【0005】 The present invention has been made in view of the above circumstances, and the problem to be solved by the present invention is to provide a refractory sheet and an electronic device case that do not require large equipment and can shorten the molding cycle to suppress manufacturing cost and man-hours. 【Means for Solving the Problems】 【0006】 In order to solve the above problems, the present invention constitutes the following refractory sheet. 【0007】 (1) A fire-resistant sheet to be housed in the case of an electronic device, wherein multiple plate-shaped laminates made of multiple substrates and a thermosetting resin are arranged in a continuous manner, and the laminates are arranged to overlap with parts of other adjacent laminates. 【0008】 (2) The fire-resistant sheet according to (1), wherein at least one of the plurality of laminates is formed having a main body portion and an overlapping portion. 【0009】 (3) The fire-resistant sheet according to (2), wherein the main body portion and the overlapping portion are formed at different positions in the thickness direction, and the overlapping portion in the laminate is arranged to overlap and in contact with at least a portion of the main body portion of another adjacent laminate. 【0010】 (4) The fire-resistant sheet according to (3), wherein the main body portion comprises a main body bottom portion and a main body side portion, the overlapping portion comprises an overlapping bottom portion and an overlapping side portion, the main body bottom portion and the overlapping bottom portion are formed at different positions in the thickness direction, the overlapping bottom portion is arranged in a state in which it overlaps and abuts with at least a portion of the main body bottom portion of an adjacent laminate, the main body side portion and the overlapping side portion are formed at different positions in the thickness direction, and the overlapping side portion is overlapped in a state in which it overlaps and abuts with at least a portion of the main body side portion of an adjacent laminate. 【0011】 (5) The fire-resistant sheet according to (4), comprising a plurality of laminates, a first laminate provided at one end of the fire-resistant sheet, a second laminate provided at the other end of the fire-resistant sheet, and at least one third laminate provided between the first laminate and the second laminate, wherein the third laminate is formed in the same shape as the shape obtained by cutting the end of the first laminate. 【0012】 (6) The fire-resistant sheet according to (4), comprising a pair of end laminates formed to be the same shape as each other and provided at both ends of the fire-resistant sheet, and at least one intermediate laminate provided between each of the end laminates. 【0013】 (7) The refractory sheet according to (1), wherein the base material is an inorganic fiber formed of artificial mineral fiber. 【0014】 (8) The refractory sheet according to (1), wherein the laminate is a cured laminate of a prepreg obtained by impregnating the base material with a phenolic resin. 【0015】 (9) The refractory sheet according to any one of (1) to (8), wherein at least a part of the laminate is disposed in contact with the case. 【0016】 Further, the present invention constitutes the following electronic device case in order to solve the above-described problems. 【0017】 (10) An electronic device case including a container and a lid, and housing the electronic device and the refractory sheet according to any one of (1) to (8) therein. 【0018】 (11) The electronic device case according to (10), wherein the refractory sheet is provided along the inner surface of the lid. 【Advantages of the Invention】 【0019】 According to the refractory sheet and the electronic device case of the present invention, it is possible to suppress the manufacturing cost and man-hours by shortening the molding cycle without requiring large-scale equipment. 【Brief Description of the Drawings】 【0020】 [Figure 1] Exploded perspective view of the battery case according to the present embodiment. [Figure 2] Cross-sectional view of the battery case according to the present embodiment. [Figure 3] Perspective view of the refractory sheet according to the present embodiment. [Figure 4] (a) to (c) are perspective views showing the constituent members of the refractory sheet. 【Mode for Carrying Out the Invention】 【0021】 With reference to FIGS. 1 and 2, a battery case 2, which is an embodiment of an electronic device case according to the present invention, will be described. The battery case 2 according to the present embodiment is used to accommodate a plurality of lithium ion batteries 3, 3,... having terminals 30, 30 (which is a form of an electronic device according to the present invention and will be simply referred to as "battery" hereinafter). Note that the fireproof sheet 1 according to the present invention is not only applicable to the battery case, but can be generally used for the case of an electronic device. 【0022】 The battery case 2 is configured to include a container 20 and a lid 21. The lid 21 is assembled to the container 20 so as to be able to open and close the opening 22 of the container 20. In the battery case 2 according to the present embodiment, a fixture (not shown) that can assemble the lid 21 to the container 20 is provided at the opening 22 of the container 20. 【0023】 As shown in FIG. 1, the batteries 3, 3,... are accommodated in the container 20 such that the upper portion including the terminals 30, 30 is exposed from the opening 22. A configuration in which a plurality of batteries 3, 3,... are arranged inside the container 20 is a conventional configuration. Also, when the lid 21 is assembled to the container 20, as shown in FIG. 2, the upper portion of the batteries 3, 3,... including the terminals 30, 30 is covered by the lid 21. 【0024】 As shown in FIGS. 1 and 2, the fireproof sheet 1 according to the present embodiment is accommodated in the battery case 2. Specifically, as shown in FIG. 2, the fireproof sheet 1 is provided by adhering the upper surfaces of the laminates 11, 12, 13 (the outer surfaces of the bottom portions described later) to the inner surface of the lid 21 in order with an adhesive C. Thus, in the present embodiment, at least a part of the laminates 11, 12, 13 is disposed in contact with the lid 21 of the battery case 2. Note that the fireproof sheet 1 may be provided on the container 20. 【0025】 As described above, in this embodiment, by sequentially bonding the multiple laminates 11, 12, and 13 to the lid 21 of the battery case 2, the external dimensions of the battery case 2 and the fire-resistant sheet 1 can be made to match, making alignment easy. 【0026】 In this embodiment, the fire-resistant sheet 1 is positioned to cover the upper side (the side closest to the cover 21) of the batteries 3, 3, etc., on which the terminals 30, 30 are located. It is preferable that the fire-resistant sheet 1 be provided on the side of the batteries 3, 3, etc., on which the terminals 30, 30 are located. 【0027】 Furthermore, in this embodiment, the flange portion of the fire-resistant sheet 1 (the first to third main flange portions 11e to 13e, and the first and third overlapping flange portions 11f and 13f, etc., described later) is positioned in the battery case 2 sandwiched between the housing 20 and the lid 21. This allows the fire-resistant sheet 1 to be easily held in the battery case 2. It also makes it easier to position the fire-resistant sheet 1 when assembling it to the lid 21. 【0028】 In this embodiment, the fire-resistant sheet 1 is provided by being bonded to the inner surface of the lid 21 in advance. However, it is also possible to configure the fire-resistant sheet 1 to be housed in the battery case 2 when assembling the lid 21 to the housing 20. In this case, the fire-resistant sheet 1 may be formed integrally in advance. In that case, it is possible to bond the main body portion and the overlapping portion of the laminates 11, 12, and 13, which will be described later. Alternatively, the fire-resistant sheet 1 may be joined to the inside of the lid 21 via double-sided tape that constitutes an impact-absorbing adhesive layer. 【0029】 In this embodiment, as described above, the fire-resistant sheet 1 is provided inside the battery case 2 so as to face the terminals 30 of the batteries 3, 3, 3. Therefore, even if one of the batteries 3, 3, 3 experiences thermal runaway and ruptures or catches fire, the spread of fire and the scattering of fragments can be suppressed. 【0030】 As shown in Figure 3, the fire-resistant sheet 1 according to this embodiment consists of multiple plate-shaped laminates made of multiple base materials and a thermosetting resin, arranged in a continuous manner. In this embodiment, the first laminate 11, the second laminate 12, and two third laminates 13-13 are arranged in a continuous manner. Furthermore, each of the laminates 11-12-13 overlaps with a portion of the adjacent laminates. 【0031】 In the fire-resistant sheet 1 according to this embodiment, each laminate 11 to 13 is formed by laminating a plurality of base materials and a release layer made of phenolic resin. The base material according to this embodiment is a woven fabric made of multifilament of inorganic fibers or warp and weft threads of spun yarn, and these warp and weft threads are impregnated with phenolic resin. 【0032】 The inorganic fibers that make up the base fabric are not particularly limited and may be natural inorganic fibers or artificial inorganic fibers. However, from the viewpoint of ease of obtaining the fabric, artificial inorganic fibers are preferred, and artificial mineral fibers are more preferred. Examples of artificial mineral fibers include glass fibers, basalt fibers, ceramic fibers, rock wool, slag wool, polycrystalline fibers, non-bio-persistent fibers, alumina fibers, silica fibers, silicon carbide fibers, and boron silicate fibers. Inorganic fibers may be used individually or in combination of two or more types. From the viewpoint of cost, glass fibers are preferred among artificial mineral fibers. Examples of glass fibers include E glass fibers, S glass fibers, R glass fibers, ECR glass fibers, C glass fibers, and AR glass fibers. Of these, E glass fibers are preferred from the viewpoint of cost and the availability of a wide variety. 【0033】 The warp and weft threads, composed of inorganic fibers, may be multifilaments or spun yarns. Both are bundles of single fibers. Multifilaments are bundles of long fibers (filaments), and spun yarns are bundles of short fibers (staples). Because they are bundles of single fibers, phenolic resin can be impregnated between the single fibers. The structure of the multifilaments is not particularly limited; they may be twisted or untwisted filaments (long fibers). Spun yarns may be made by twisting short fibers (staples) according to a standard method. Furthermore, the warp and weft threads may be bulkyed or otherwise treated to increase bulkiness. By controlling the amount of phenolic resin impregnated between the filaments constituting the multifilaments of the warp or weft, or between the short fibers constituting the spun yarn, within a predetermined range, it becomes possible to effectively suppress the release of phenolic resin decomposition gases to the outside at high temperatures. The fiber diameters of the filaments and staples can be determined as appropriate. 【0034】 Fabrics made of inorganic fibers are formed by the interlocking of warp and weft threads, and there are no particular limitations on the structure of the fabric; various weave structures can be used. For example, single weave, double weave, and leno weave are examples. Of these, single weave is preferred. Examples of single weaves include the three basic weaves of plain weave, twill weave, and satin weave, variations of these, mixed weaves which are a mixture of the three basic weaves and variations, and weaves which do not rely on the three basic weaves or variations. Of these, plain weave is preferred from the viewpoint of ease of availability and because the weave is less likely to spread during compression molding when forming laminates 11-13, and the base material can be kept in a denser state. 【0035】 The thickness of the base fabric should be such that the total thickness of the laminates 11-13 is 3 mm or less, and can be appropriately determined according to the properties and thickness of the fire-resistant sheet 1, the number of layers of the base fabric, etc. From the viewpoint of reducing the weight and cost of the laminates 11-13, the thickness of the raw fabric is preferably 0.05-3.0 mm, and more preferably 0.15-2.0 mm. 【0036】 The fabric or inorganic fibers constituting the base material may be surface-treated or untreated. Examples of surface treatments include silane coupling treatment, titanium coupling treatment, and plasma coating treatment. 【0037】 The number of layers of the base material in the laminates 11 to 13 can be appropriately determined according to the properties and thickness of the fire-resistant sheet 1. From the viewpoint of ease of processing, 2 to 25 is preferred, and 2 to 15 is more preferred. 【0038】 The release layer in the laminates 11-13 is made of phenolic resin. The release layer connects the substrates and, being made of phenolic resin, allows for good impregnation between the single fibers constituting the substrate (woven fabric), making it possible to impart appropriate heat insulation, heat resistance, and impact resistance to flames based on the properties of phenolic resin. For example, because phenolic resin has a high residual char rate after combustion, it is possible to provide a fire-resistant sheet 1 that has excellent performance in maintaining the product shape even after the laminates 11-13 have been exposed to high heat. Furthermore, phenolic resin is readily available and advantageous in terms of cost. From the viewpoint of impact resistance and heat resistance, the phenolic resin content in the laminates 11-13 is preferably 20-50% by weight. 【0039】 The release layer is preferably formed of a phenolic resin, but may further contain other curable resins. Alternatively, the phenolic resin may be replaced with another curable resin. The phenolic resin can be prepared according to standard methods, but commercially available resins can also be used. Examples of such other curable resins include thermosetting polyimides, melamine resins, urea resins, silicone resins, furan resins, and benzoxazine resins. The other curable resins may be used individually or in combination of two or more. 【0040】 The phenolic resin that forms the release layer can be any reaction product of phenols and aldehydes, and known resins can be used. The phenols are not particularly limited and include alkylphenols (cresol, xylenol, etc.), polyhydric phenols (resorcinol, etc.), phenylphenol, aminophenol, etc. The aldehydes are also not particularly limited and include formaldehyde, paraformaldehyde, acetaldehyde, furfural, etc. The phenolic resin may be of the resol type or novolac type. Modified phenolic resins may also be used. From the viewpoint of ease of impregnation into the substrate, resol-type phenolic resins are preferred. The phenolic resin may be used alone or in combination of two or more types. 【0041】 Examples of novolac-type phenolic resins include cresol novolac resins and bisphenol A type novolac resins. Examples of resol-type phenolic resins include methylol-type resol resins and dimethylene ether-type resol resins. Examples of modified phenolic resins include arylalkylene-type phenolic resins, and more specifically, phenol aralkyl resins. 【0042】 Phenolic resins may contain a curing agent as needed. For example, in the case of novolac-type phenolic resins and arylalkylene-type phenolic resins, hexamethylenetetramine is usually suitably used. Phenolic resins may also contain other additives besides curing agents as needed. Examples of such additives include flame retardants, inorganic fillers, ultraviolet absorbers, antioxidants, dyes, pigments, and foaming agents. 【0043】 The flame retardants are not particularly limited and include, for example, brominated flame retardants, phosphorus-based flame retardants, hydrated metal compound-based flame retardants, silicone-based flame retardants, nitrogen-containing compounds, hindered amine compounds, organometallic compounds, and aromatic engineering plastics. These may be used individually or in combination of two or more. 【0044】 The inorganic filler is not particularly limited and includes, for example, silica such as molten crushed silica, molten spherical silica, crystalline silica, secondary aggregated silica, and fine powder silica; metal compounds such as alumina, silicon nitride, aluminum nitride, boron nitride, titanium oxide, silicon carbide, aluminum hydroxide, magnesium hydroxide, and titanium white; and inorganic minerals such as glass bubbles, kaolin clay, talc, mica, calcium carbonate, wollastonite, montmorillonite, smectite, bentonite, and sepiolite. These may be used individually or in combination of two or more. 【0045】 The fire-resistant sheet 1 may be a laminate 11 to 13 comprising multiple substrates and a release layer made of phenolic resin, but it is preferable that it be a laminated cured product of prepregs impregnated with phenolic resin. This laminated cured product can be manufactured using, for example, a prepreg obtained by the wet method as shown below, but is not limited to this, and can also be manufactured using a prepreg obtained by the hot melt method or spray coating. 【0046】 First, a phenolic resin varnish is prepared by mixing the phenolic resin, any additives added as needed, and a solvent. There are no particular limitations on the solvent that can be used for the varnish; any solvent used in the preparation of this type of varnish can be used. Examples include water and organic solvents. The organic solvent may be water-soluble or water-insoluble, but a water-soluble organic solvent is preferred. Examples of water-soluble organic solvents include monohydric alcohols with 1 to 3 carbon atoms, acetone, and cyclic ethers such as tetrahydrofuran. 【0047】 Next, the varnish is impregnated into the substrate and then dried / solidified to obtain a prepreg impregnated with phenolic resin. By drying, volatile components such as solvents vaporize and solid components such as phenolic resin solidify. The impregnation rate (RC) of phenolic resin to the substrate is not particularly limited, but 40-70% based on solid content is preferred. This impregnation rate can be controlled, for example, by adjusting the distance between the rolls when passing the varnish-impregnated substrate between two rolls. Next, the prepregs are laminated and heated and pressurized to cure the phenolic resin prepolymer, thereby obtaining laminates 11-13 of phenolic resin and multiple substrates, i.e., laminated cured prepregs. 【0048】 As shown in Figures 3 and 4(a), the first laminate 11 provided at one end of the fire-resistant sheet 1 according to this embodiment is composed of a first main body bottom surface portion 11a, a first overlapping bottom surface portion 11b, a first main body side surface portion 11c, a first overlapping side surface portion 11d, a first main body flange portion 11e, a first overlapping flange portion 11f, a first main body end surface portion 11g, and a first end flange portion 11h. 【0049】 The first main body bottom portion 11a and the first overlapping bottom portion 11b constitute the upper surface of the fire-resistant sheet 1. The first overlapping bottom portion 11b is formed to be slightly above the first main body bottom portion 11a. The first main body side portion 11c and the first overlapping side portion 11d constitute both sides of the fire-resistant sheet 1 in the shorter direction. The first overlapping side portion 11d is formed to be slightly to the side and outward from the first main body side portion 11c. 【0050】 The first main flange portion 11e and the first overlapping flange portion 11f constitute the peripheral edge of the fire-resistant sheet 1. The first overlapping flange portion 11f is formed slightly above the first main flange portion 11e. The first main end face portion 11g constitutes the longitudinal side surface of the fire-resistant sheet 1. The first end flange portion 11h constitutes the peripheral edge continuous with the first main end face portion 11g. 【0051】 In the first laminate 11, the first main body bottom portion 11a, the first main body side portion 11c, and the first main body flange portion 11e are formed as the main body portion. In addition, in the first laminate 11, the first superimposed bottom portion 11b, the first superimposed side portion 11d, and the first superimposed flange portion 11f are formed as superimposed portions at different positions in the thickness direction from the main body portion. 【0052】 As shown in Figures 3 and 4(b), the second laminate 12 provided at the other end of the fire-resistant sheet 1 according to this embodiment is composed of a second main body bottom surface portion 12a, a second main body side surface portion 12c, a second main body flange portion 12e, a second main body end surface portion 12g, and a second end flange portion 12h. 【0053】 The second main body bottom portion 12a constitutes the top surface of the fire-resistant sheet 1. The second main body side portion 12c constitutes both sides of the fire-resistant sheet 1 in the short direction. The second main body flange portion 12e constitutes the peripheral edge of the fire-resistant sheet 1. The second main body end portion 12g constitutes the side of the fire-resistant sheet 1 in the long direction. The second end flange portion 12h constitutes the peripheral edge continuous with the second main body end portion 12g. 【0054】 As shown in Figures 3 and 4(c), the third laminate 13 provided between the first laminate 11 and the second laminate 12 in the fire-resistant sheet 1 according to this embodiment is composed of a third main body bottom surface 13a, a third overlapping bottom surface 13b, a third main body side surface 13c, a third overlapping side surface 13d, a third main body flange 13e, and a third overlapping flange 13f. 【0055】 The third main body bottom surface 13a and the third overlapping bottom surface 13b constitute the upper surface of the fire-resistant sheet 1. The third overlapping bottom surface 13b is formed slightly above the third main body bottom surface 13a. The third main body side surface 13c and the third overlapping side surface 13d constitute both sides of the fire-resistant sheet 1 in the shorter direction. The third overlapping side surface 13d is formed slightly to the outside of the third main body side surface 13c. The third main body flange 13e and the third overlapping flange 13f constitute the peripheral edge of the fire-resistant sheet 1. The third overlapping flange 13f is formed slightly above the third main body flange 13e. 【0056】 In the third laminate 13, the third main body bottom portion 13a, the third main body side portion 13c, and the third main body flange portion 13e are formed as the main body portion. In addition, in the third laminate 13, the third superimposed bottom portion 13b, the third superimposed side portion 13d, and the third superimposed flange portion 13f are formed as superimposed portions at positions different from the main body portion in the thickness direction. 【0057】 In the fire-resistant sheet 1 according to this embodiment, the third laminate 13 is formed in the same shape as the first laminate 11 obtained by cutting the end of the laminate along the cutting line L (see Figure 4(a)). Therefore, the third laminate 13 can be manufactured using the same mold as the first laminate 11. 【0058】 In the fire-resistant sheet 1 according to this embodiment, the overlapping portion of each laminate is arranged in a state where it overlaps and abuts with at least a portion of the main body of the adjacent laminate. Specifically, as shown in Figures 2 and 3, the first overlapping bottom surface portion 11b of the first laminate 11 is arranged in a state where it overlaps and abuts with the third main body bottom surface portion 13a of the adjacent third laminate 13. Also, the first overlapping side surface portion 11d of the first laminate 11 is arranged in a state where it overlaps and abuts with the third main body side surface portion 13c of the adjacent third laminate 13. Furthermore, the first overlapping flange portion 11f of the first laminate 11 is arranged in a state where it overlaps and abuts with the third main body flange portion 13e of the adjacent third laminate 13. 【0059】 Furthermore, as shown in Figures 2 and 3, the third overlapping bottom surface portion 13b of the third laminate 13 is positioned in a state of overlapping contact with the third main body bottom surface portion 13a of the adjacent third laminate 13 or the second main body bottom surface portion 12a of the second laminate 12. Also, the third overlapping side surface portion 13d of the third laminate 13 is positioned in a state of overlapping contact with the third main body side surface portion 13c of the adjacent third laminate 13 or the second main body side surface portion 12c of the second laminate 12. Furthermore, the third overlapping flange portion 13f of the third laminate 13 is positioned in a state of overlapping contact with the third main body flange portion 13e of the adjacent third laminate 13 or the second main body flange portion 12e of the second laminate 12. 【0060】 In this embodiment, the flange portion of the fire-resistant sheet 1 (first to third main flange portions 11e to 13e, and first and third overlapping flange portions 11f to 13f, etc.) makes it easy to position the fire-resistant sheet 1 when assembling it to the battery case 2 (lid 21 or housing 20). It is also possible to configure the fire-resistant sheet 1 without providing a flange portion. 【0061】 In the fire-resistant sheet 1 according to this embodiment, the overlapping portions of each laminate 11 and 13 are arranged to overlap and contact at least a portion of the main body of the adjacent laminates 12 and 13. Thus, the fire-resistant sheet 1 according to this embodiment is constructed by overlapping multiple laminates 11, 12, and 13. For this reason, large equipment is not required to mold the fire-resistant sheet 1. Furthermore, since each laminate 11, 12, and 13 is smaller than when the fire-resistant sheet 1 is integrally molded, it is possible to shorten the molding cycle and reduce manufacturing costs and man-hours. 【0062】 In addition to the method of fitting together using stepped shapes as in this embodiment, the method of overlapping parts of each laminate 11, 12, and 13 can also be adopted by fitting them together with concave and concave shapes. That is, each laminate 11, 12, and 13 has a portion that overlaps without using other members, and there should be no gaps between the laminates 11, 12, and 13 when they are superimposed on each other. 【0063】 In the fire-resistant sheet 1 according to this embodiment, by sequentially assembling a plurality of laminates 11, 12, and 13 onto the battery case 2 (lid 21 or housing 20), it is possible to form the fire-resistant sheet 1 to match the shape of the battery case 2. That is, since the external dimensions of the battery case 2 and the fire-resistant sheet 1 can be matched, it becomes possible to easily align the fire-resistant sheet 1 with respect to the battery case 2. 【0064】 Furthermore, in the fire-resistant sheet 1 according to this embodiment, the overlapping portions of each laminate 11 and 13 are configured to overlap outside the main body portions of the adjacent laminates 12 and 13, but it is also acceptable to configure the overlapping portions to overlap inward from the main body portions. 【0065】 Furthermore, the fire-resistant sheet according to the present invention may also be configured as a laminate of multiple sheets, comprising a pair of end laminates formed to be the same shape and provided at both ends of the fire-resistant sheet, and at least one intermediate laminate provided between each end laminate. In this case, the pair of end laminates and the intermediate laminate are arranged in a state in which parts of them overlap and come into contact with each other. 【0066】 Furthermore, in the fire-resistant sheet 1 according to this embodiment, the first and third overlapping bottom surfaces 11b and 13b of the laminates 11 and 13 are arranged in a state where they overlap and come into contact with parts of the second and third main body bottom surfaces 12a and 13a of the adjacent laminates 12 and 13. Also, the first and third overlapping side surfaces 11d and 13d of the laminates 11 and 13 are arranged in a state where they overlap and come into contact with parts of the second and third main body side surfaces 12c and 13c of the adjacent laminates 12 and 13. In this way, the fire-resistant sheet 1 is configured so that the laminates 11, 12, and 13 can overlap even if the shape is three-dimensional, such as the lid 21 of the battery case 2. In other words, it becomes possible to protect the inner surface of the lid 21 in a three-dimensional manner. 【0067】 Furthermore, in the fire-resistant sheet 1 according to this embodiment, the first and third overlapping flange portions 11f and 13f of the laminates 11 and 13 are arranged to overlap and abut against parts of the second and third main flange portions 12e and 13e of the adjacent laminates 12 and 13. In this way, the fire-resistant sheet 1 is configured such that the laminates 11, 12, and 13 can overlap even in the portion of the battery case 2 that is positioned between the housing 20 and the lid 21. 【0068】 The applicant has demonstrated through testing that the fire resistance performance of the fire-resistant sheet 1 according to this embodiment is improved by overlapping a portion of one laminate with a portion of another adjacent laminate. The details of the test are described below. 【0069】 The applicant attached a fire-resistant sheet 1 (a laminate of two 1.2 mm thick sheets stacked together with a width of 60 mm) according to the present invention to a 1.0 mm thick SUS plate (hereinafter referred to as the "test specimen") and irradiated it with a flame from a gas burner at 1100 degrees Celsius from the side of the fire-resistant sheet 1, and measured the temperature of the flame and the surface in contact with the flame. 【0070】 Furthermore, the applicant irradiated a 1100-degree gas burner flame from the side of the fire-resistant sheet 1 onto a 1.0 mm thick SUS plate with one 1.2 mm thick laminate used in the present invention attached to it (hereinafter referred to as "Comparative Example 1"), and measured the temperature of the flame and the flame-facing surface. 【0071】 Furthermore, the applicant also applied a 1100-degree gas burner flame to a 1.0 mm thick SUS plate, which was made by butting (without overlapping) two 1.2 mm thick laminates used in the present invention onto it (hereinafter referred to as "Comparative Example 2"), and measured the temperature of the flame and the surface in contact with the flame. 【0072】 Furthermore, the applicant irradiated a 1.0 mm thick SUS plate with a 1100-degree gas burner flame from the side of the fire-resistant sheet 1 and measured the temperature of the flame and the flame-facing surface (hereinafter referred to as "SUS plate only"). 【0073】 The test results are described below. In the case of SUS plate alone, the temperature exceeded 600 degrees Celsius 3 minutes after flame irradiation. In the case of Comparative Example 1, the temperature rose to 162 degrees Celsius 10 minutes after flame irradiation. In the case of Comparative Example 2, the temperature rose to 338 degrees Celsius 10 minutes after flame irradiation, and a gap was observed at the joint. 【0074】 On the other hand, in the case of the test specimen, the temperature rise after 10 minutes from flame irradiation was limited to 173 degrees. Thus, the fire-resistant sheet 1 according to the present invention was able to achieve the same level of heat insulation performance as a single seamless laminate by overlapping the laminates with each other. In other words, it was confirmed that the fire-resistant sheet 1 according to this embodiment improves fire resistance by overlapping a portion of one laminate with a portion of another adjacent laminate. [Explanation of symbols] 【0075】 1. Fireproof sheet 2. Battery case (electronic device case) 3. Lithium-ion batteries (electronic devices) 11 First laminate 11a Bottom surface of the first main body 11b First superimposed bottom part 11c First main body side part 11d First overlapping side section 11e First main body flange section 11f First overlapping flange portion 11g First end face portion of the main body 11h First end flange 12 Second laminate 12a Bottom surface of the second main body 12c Second body side part 12e Second body flange part 12g Second body end face portion 12h Second end flange portion 13 Third laminate 13a Bottom surface of the third main body 13b Third superimposed bottom part 13c Third main body side part 13d Third overlapping side section 13e Third main body flange section 13f Third layered guard section 20. Inner container 21. Lid 22 Opening 30 terminals C Adhesive L Cutting line

Claims

[Claim 1] A fire-resistant sheet housed in the case of an electronic device, Multiple plate-like laminates, each consisting of multiple substrates and a thermosetting resin, are arranged in a continuous manner. The laminate is a fire-resistant sheet arranged to overlap with a portion of another adjacent laminate. [Claim 2] The fire-resistant sheet according to claim 1, wherein at least one of the plurality of laminated bodies is formed having a main body portion and an overlapping portion. [Claim 3] The main body and the superimposed portion are formed at different positions in the thickness direction. The fire-resistant sheet according to claim 2, wherein the overlapping portion in the laminate is arranged in a state in which it overlaps with and abuts at least a portion of the main body portion of another adjacent laminate. [Claim 4] The main body comprises a bottom surface and a side surface, The superimposed portion comprises a superimposed bottom surface portion and a superimposed side surface portion, The main body bottom portion and the superimposed bottom portion are formed at different positions in the thickness direction. The overlapping bottom surface portion is arranged in a state in which it overlaps with and abuts at least a portion of the bottom surface portion of the main body of the other adjacent laminated body. The main body side portion and the superimposed side portion are formed at different positions in the thickness direction. The fire-resistant sheet according to claim 3, wherein the overlapping side portion is arranged in a state in which it overlaps with and abuts at least a portion of the main body side portion of another adjacent laminate. [Claim 5] The laminate comprises a first laminate provided at one end of the fire-resistant sheet, a second laminate provided at the other end of the fire-resistant sheet, and at least one third laminate provided between the first laminate and the second laminate. The fire-resistant sheet according to claim 4, wherein the third laminate is formed in the same shape as the shape obtained by cutting the end of the first laminate. [Claim 6] The fire-resistant sheet according to claim 4, comprising a pair of end laminates formed to be the same shape as each other and provided at both ends of the fire-resistant sheet, and at least one intermediate laminate provided between each of the end laminates. [Claim 7] The fire-resistant sheet according to claim 1, wherein the base material is made of inorganic fibers which are artificial mineral fibers. [Claim 8] The fire-resistant sheet according to claim 1, wherein the laminate is a laminated cured product of a prepreg in which a phenolic resin is impregnated into the substrate. [Claim 9] The fire-resistant sheet according to any one of claims 1 to 8, wherein at least a portion of the laminate is arranged in contact with the case. [Claim 10] An electronic device case comprising a housing and a lid, for housing the electronic device and a fire-resistant sheet according to any one of claims 1 to 8. [Claim 11] The electronic device case according to claim 10, wherein the fire-resistant sheet is provided along the inner surface of the lid.

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