JP2018179010A - Fireproof insulation sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refractory heat insulating sheet which is thin and lightweight, has flexibility and can provide a refractory heat insulating sheet having excellent fire resistance. SOLUTION: This is a fire-resistant heat insulating sheet in which a laminated type heat insulating material is housed in a bag made of a fire resistant fiber woven fabric, and the laminated type heat insulating body is a non-woven fabric of silica-based inorganic fiber having a hydroxyl group. At least one heat energy consuming layer composed of; one layer less reflective material composed of a base material with a metal layer having a metal layer on the surface of the base material or a metal foil; and graphite crystals oriented in the plane direction. It is a laminated body in which at least one layer of graphite layers is laminated. [Selection diagram] Fig. 1

Description

  The present invention compactly encapsulates communication cables, dispatch cables and the like from fires and other flames, and delays the time to reach a high temperature that may damage the cables (especially the cable sheathing). It can be related to a fireproof insulation sheet.

With the recent advancement of high-level computerization, there is a demand for measures to protect optical fibers, communication cables, dispatch cables and the like from sudden disasters such as fires.
In particular, when the cable sheathing burns, a short circuit between the cables occurs, and communication control and power supply become impossible, so it is required to take measures to prevent the spread of fire to these communication networks.
Furthermore, in a power plant such as a nuclear power plant, it is very important to protect communication cables and dispatch cables from sudden fires and the like.

  In recent years, a method of covering cable bundles with a non-combustible and non-combustible fire-resistant insulation sheet, and measures to prevent the spread of fire by sprinkling water or digestive gas fullness have been taken. The fire protection measures using the fireproof insulation sheet have an advantage of being able to cope with a case where there is a space limitation or a corner portion such as a bend as a fire prevention measure for a cable or the like which is complicatedly wired.

  The fireproof insulation sheet used for fire prevention measures as described above is not only excellent in heat insulation, but also light in weight and flexible so that the cable can be compactly packaged because the cable rack periphery is narrow. It is also necessary to have good handling. The fireproof insulation sheet generally used is a fireproof felt made of ceramic fibers in a sheet form by needle punching etc., a soft type fireproof ceramic fiber blanket of 10 to 20 mm in thickness, and a plurality of these as required. And those covered with a heat resistant woven fabric.

  For example, in JP-A-2002-95119 (patent document 1), as a fireproof insulation sheet for cable protection, which is thin and easy to attach to a cable bundle, a fiber fireproof material such as ceramic fiber or alumina fiber is used. A fire resistant sheet consisting of a compression molded product has been proposed. The fireproof sheet prevents the fibrous fireproofing material from being dusted and leaking to the outside by housing the compression-molded product in the fireproof cloth bag.

  In addition to the fireproof insulation sheet made of ceramic fiber, an expansion-type fireproof that generates non-combustible gas and expands with the rise of temperature such as fire, and carbonizes itself to form a carbonized insulation layer with pores. A sheet has also been proposed (e.g., JP-A-2000-192570 (Patent Document 2)).

  On the other hand, as a structure like a fire barrier, for example, JP-A-2006-527152 (Patent Document 3) includes at least one alkali silicate resin composition layer and an expandable material layer (for example, an expanded graphic sheet) ), Reflectors (for example, foils or plates of highly reflective metals such as aluminum, nickel and chromium), heat insulators (for example, various ceramic materials such as alumina and silicates), corrugated layers having a confined gas region, etc. A combined fire resistant laminate (panel) has been proposed.

JP 2002-95119 A JP 2000-192570 A Japanese Patent Application Publication No. 2006-527152

  By the way, in facilities equipped with important equipment that is greatly affected by damage such as communication cables, for example, in a nuclear power plant, cable damage by fire may lead to a serious accident. Even if it is exposed for a long time, severe fire resistance is required such that it does not burn and keeps cables and the like at the heat resistant temperature or less of the cable covering material, for example, 200 ° C. or less.

With regard to the heat insulation performance of a general heat insulating material, since thickness is a parameter, in the case of a fireproof sheet made of ceramic fiber or a fireproof sheet composed mainly of glass fibers, in order to satisfy the above fire resistance performance. It is necessary to be 50 mm or more. Since the flexibility decreases in proportion to the thickness of the sheet, it is difficult to apply a fireproof heat insulating sheet having a thickness of 50 mm or more at a bending specification such as a corner.
In addition, for complex wiring networks where cables are wired in multiple stages and sprinklers are installed, the thickness of the fireproof insulation sheet can be applied to a space of 50 mm or less from the viewpoint of the sprinkler efficiency of sprinklers. Need to be as thin as
As described above, the fireproof thermal insulation sheet for encapsulating the cable bundle is required to be flexible, light in weight, and thin while satisfying the fire resistance performance.

  The present invention has been made in view of the above circumstances, and the object of the present invention is a safe material not restricted by the Industrial Safety and Health Act, which is thin, lightweight, flexible, and cable wiring. It is an object of the present invention to provide a fireproof insulation sheet capable of imparting a desired fire resistance performance by encapsulation even at a site where space restrictions are severe such as communication networks.

The fireproof thermal insulation sheet of the present invention is a fireproof thermal insulation sheet in which a laminate type heat insulator is housed in a bag body formed of fireproof fiber woven fabric, and the laminate type heat insulator is a silica-based material having a hydroxyl group. At least one thermal energy consuming layer composed of inorganic fiber non-woven fabric;
At least one layer consisting of a metal layer-coated substrate or metal foil having a metal layer on the substrate surface or a reflector composed of metal foil; and at least one graphite layer in which graphite crystals are oriented in the plane direction; It is a body.

The laminated type heat insulator preferably includes a laminated unit in which the graphite layer is laminated on one side of the heat energy consuming layer.
Moreover, it is preferable to include the lamination | stacking unit in which the said reflector was laminated | stacked on both surfaces of the said heat energy consumption layer.
Further, it is preferable to include a laminated unit in which a reflector, a graphite layer, a thermal energy consumption layer, and a reflector are laminated in this order.

The laminated type heat insulator may further include an airgel support sheet in which a silica airgel having a porosity of 70% or more is supported on a sheet-like fiber mass.
When the airgel support sheet is included, it is preferable that at least one energy consumption layer is disposed between the graphite layer and the airgel support sheet.

It is preferable that at least one outermost surface of the laminated type heat insulator is the reflector.
Preferably, the graphite layer is an expanded graphite sheet.
Moreover, it is preferable that the said base material with a metal layer is a metal vapor deposition fabric by which metal is vapor-deposited on the surface of the fabric which weaves and weaves glass fiber, a silica fiber, ceramic fiber, or mineral fiber.

  The heat-resistant insulation sheet of the present invention can conduct heat in the entire surface direction even when heated locally, and can effectively attenuate the heat energy. Therefore, the fireproof thermal insulation sheet of the present invention is lightweight, thin, flexible, and has excellent thermal insulation, which is convenient for attaching a sheath, a corner portion and the like of a cable bundle.

It is a schematic cross section showing the composition of the fireproof heat insulation sheet of one embodiment of the present invention. It is a schematic diagram which shows the usage example of the fireproof thermal insulation sheet | seat of a division | segmentation type. It is a temperature chart which shows the result of the generated water confirmation experiment of a heat energy consumption layer about the fireproof insulation sheet created in the example. It is a figure for demonstrating the combustion evaluation test performed in the Example. Fireproof insulation sheet No. 1 and No. 1 It is a graph which shows the back surface temperature measurement result of 2. FIG. Fireproof insulation sheet No. It is the photograph which imaged the state of each layer after the 2 combustion test. Fireproof thermal barrier sheet No. It is the photograph which imaged the state of each layer after the 4 combustion test.

FIG. 1: is a schematic cross section which shows the structure of the fireproof heat insulation sheet | seat 10 of typical embodiment of this invention. The fireproof thermal insulation sheet 10 shown in FIG. 1 accommodates the laminated type heat insulator 2 in a bag 1 formed of fireproof fiber woven fabric.
Hereinafter, the bag and the laminated type heat insulator will be described in detail.

<Laminated type insulation>
[Components of Laminate]
First, each layer which comprises the lamination | stacking type heat insulation body used as the main body of the fireproof insulation sheet | seat of this invention is demonstrated.

(1) Thermal energy consumption layer (F)
The heat energy consuming layer is a layer capable of exerting a heat insulating effect by itself consuming heat energy, and specifically, is constituted by a non-woven fabric made of a silica based inorganic fiber having a hydroxyl group.
The silica-based inorganic fiber having a hydroxyl group used in the present invention has 81% by weight or more of SiO ₂ , and Si (OH) is present in a part of the network of SiO −. Dehydration condensation reaction of the formula occurs to produce H ₂ O.

The composition of the above-mentioned silica-based inorganic fiber is not particularly limited, but preferably has the following composition.
SiO ₂ : 81 to 97% by weight;
Al ₂ O ₃ : _{3 to} 19% by weight; and ZrO ₂ , TiO ₂ , Na ₂ O, Li ₂ O, K ₂ O, CaO, MgO, SrO, BaO, Y ₂ O ₃ , La ₂ O ₃ , Fe ₂ 2% by weight or less of components selected from O ₃ and mixtures thereof (referred to as “other components”).

Specifically, the starting glass material having the following composition is melted,
55 to 80% by weight of _SiO 2,
5 to 19% by weight of Al ₂ O ₃ ,
15 to 26% by weight Na ₂ O,
0-12 wt% of _ZrO 2,
0-12 wt% of TiO _2, and _{Li 2 O, K 2 O,} CaO, MgO, SrO, BaO, Y 2 O 3, La 2 O 3, Fe 2 O 3, and mixtures thereof: 1.5 wt %Less than;
Forming filaments or staple fibers from the melt;
Acid extracting the resulting filaments or staple fibers;
It can be produced by removing residual acid and / or salt residue from the extracted filaments or staple fibers and then drying.

In the acid treatment, alkali metal ions are replaced with protons by acid treatment, but the ions (Al ³⁺ , TiO ²⁺ or Ti ⁴⁺ , and ZrO ²⁺ or Zr ⁴⁺ ) will remain in the Si-O network. Metal ions substituted by protons in the silicon dioxide backbone are believed to leave a certain number of hydroxyl groups, depending on valence. These hydroxyl groups undergo a condensation reaction at about 600 to 800 ° C. as in the above formula (1) to form a new Si—O—Si bond and release H ₂ O.

  Water generated by dehydration condensation is vaporized in a high temperature atmosphere. At this time, since the heat energy given to the nonwoven fabric made of silica-based inorganic fiber is consumed as the heat of vaporization, the temperature rise of the nonwoven fabric can be suppressed.

The silica-based inorganic fiber constituting the non-woven fabric is not particularly limited as long as it is a silica-based inorganic fiber in which Si (OH) is contained in the composition, for example, AlO _1.5 · 18 [(SiO ₂ ) _0.6 (SiO _1.5 OH) The composition represented by _0.4 ] is mentioned.
The inorganic fiber having such composition has a diameter of about 6 to 13 μm, preferably about 7 to 10 μm, a staple fiber having a length of 3 to 30 mm, or a diameter of 6 to 13 μm, preferably about 7 to 10 μm by melt spinning. It can be manufactured as a filament of about 30 to 150 mm in length. Both the filaments and staple fibers are substantially free of shot because they are produced by continuous spinning after melting. For this reason, it clears the safety standards of the Labor Safety and Health Act enforcement order and is not subject to the regulation under the Specific Chemical Substances Hazard Prevention Regulations.

  A commercially available thing can be used as such a silica type inorganic fiber, For example, BELCOTEX (trademark) of belChem Fiber Materials GmbH, etc. can be used.

  BELCOTEX® fibers are generally made from silicic acid modified with alumina, and for standard type staple fiber pre-yarns, have an average denier of about 550 tex. BELCOTEX® fibers are amorphous, generally about 94.5 weight percent silica, about 4.5 weight percent alumina, less than 0.5 weight percent oxide, and 0.5 weight percent Contains less than a percent of other ingredients. There is little variation in diameter with an average diameter of about 9 μm, and there is heat resistance up to 1100 ° C. with a melting point of 1500 ° C. to 1550 ° C.

  A non-woven fabric using such a silica-based inorganic fiber can be produced by intermingling fibers formed by a wet method or a dry method with a conventionally known method such as a water flow entanglement method or a needle punch method.

  The thickness of the heat energy consuming layer formed of the non-woven fabric made of silica-based inorganic fibers as described above is not particularly limited, but is preferably 3 to 10 mm, more preferably 5 to 7 mm. If it is too thin, sufficient thermal energy attenuation can not be obtained in relation to the amount of fiber, and as a result, sufficient thermal insulation performance can not be obtained. On the other hand, if the thickness is too large, in the case of a multilayer structure, the number that can be incorporated in the laminate is limited in relation to the overall thickness, which makes it difficult to obtain the effects of the present invention. .

In addition, a silica-based inorganic fiber non-woven fabric may be used alone as a heat energy consuming layer (F), or as a lamination unit of “R / F / R” in which a reflective material (R) is attached on both sides, It may be used.
By using such a lamination unit, water generated by dehydration condensation is vaporized without being diffused to other layers, so that thermal energy is effectively consumed in the non-woven fabric made of silica-based inorganic fibers. it can.

(2) Reflective material (R)
The reflector is a layer having a role of reflecting thermal energy, and a metal foil or a substrate with a metal layer in which a metal is vapor-deposited or a metal foil is laminated on the surface of the substrate is used.

Examples of the metal used for metal foil or metal deposition include highly reflective metals such as aluminum, stainless steel, titanium, chromium, nickel and gold, with preference given to aluminum.
The metal foil of such a highly reflective metal, preferably an aluminum foil, is usually 5 to 25 μm, preferably 10 to 18 μm. If the thickness is too large, the rigidity is too large, which leads to a decrease in flexibility of the finally formed fireproof insulation sheet, which in turn leads to a decrease in the handleability of the fireproof insulation sheet.

  A plastic film or a cloth is used as a base material used for the said base material with a metal layer.

  As the plastic film, a polyolefin film such as polyethylene and polypropylene, a polyester film, a polycarbonate film, a polyamide film and the like can be used, and preferably a polyethylene terephthalate (PET) film having a high heat resistance temperature. Although the thickness of the plastic film to be used is not particularly limited, it is usually 8 μm to 500 μm, preferably 8 to 300 μm, more preferably 10 to 100 μm. If it is too thin, its role as a substrate will be insufficient, and if it is too thick, it will cause an increase in the thickness of the laminated type heat insulating material, making it difficult to make the fireproof heat insulation sheet thinner and secure the desired heat insulation performance.

A woven fabric or a knitted fabric is preferably used as the fabric from the viewpoint of thinness. As yarns (fibers) constituting the fabric, natural fibers such as rayon fibers or semi-synthetic fibers; synthetic fibers such as aramid fibers or polyester fibers; metal fibers; ceramic fibers; mineral fibers; glass fibers; carbon fibers etc. Of these, glass fibers, silica fibers, ceramic fibers, and mineral fibers are preferable from the viewpoint of heat resistance, and more preferably glass fibers are used from the viewpoint of heat resistance and cost. The heat resistance of glass fiber depends on the composition, but it is usually 600 to 800 ° C with general-purpose type E glass (SiO ₂ : 50 to 60%, Al ₂ O ₃ : 10 to 15%), metal layer Higher than the melting point (about 660 ° C.) of aluminum preferably used as
Therefore, when using a substrate with a metal layer as a reflector, the thickness is preferably 50 μm to 2.5 mm, more preferably 0.1 mm to 1 mm, and a glass fiber woven fabric is used as a substrate and metal is deposited on one side or both sides. Or the base material with a metal layer which affixed metal foil is mentioned.

  In addition, metal is vapor-deposited on both sides of the plastic film on one surface of the cloth such as a glass fiber woven fabric as well as the metal-layer-provided substrate in which metal is directly vapor-deposited or metal foil is adhered to the surface of the fabric or plastic film. It may be a mixed type metal layer coated substrate to which a metal layer coated substrate is attached. A commercially available thing may be used as a base material with a mixed type metal layer. For example, GENTEX Corp. And DualMirror (registered trademark).

When a metal foil is used as the reflector, it can serve as a reflector with almost no influence on the thickness of the fireproof insulation sheet.
On the other hand, in the case of a substrate with a metal layer, although depending on the type of substrate, it tends to be thicker than metal foil, and the weight also increases. However, as in the case of using a glass fiber fabric as the base material, the base material having a melting point higher than the melting point of the metal layer can cause the metal foil to be burnt out even if the base material is burnt out. This has the advantage that the metal layer is retained and the shape of the laminated type thermal insulator can also be retained. Moreover, the heat insulation effect based on the glass fiber cloth is also obtained. Therefore, within the allowable range of thickness and weight, a metal foil and a substrate with a metal layer (or a substrate with a mixed type metal layer) may be used as a unit attached, or in a laminate, a substrate with a metal foil and a metal layer It is preferable to use both of the materials (or the mixed type metal layer-provided substrate) as the reflector.

The metal foil and the substrate with a metal layer may be contained alone or in combination in the laminate-type heat insulator of the present invention. For example, the reflector may be configured in a state in which two or more metal foils are stacked, or the reflector may be configured by overlapping the metal foil and the metal layer-attached substrate.
When the reflective material is a plurality of metal foils, a substrate with a metal layer, or a combination thereof, the types of metal constituting the metal foil and / or the substrate with a metal layer to be used may be the same. It may be a combination of different types. In addition, when using a plurality of metal layer-provided substrates, as the substrate of the metal layer-provided substrate, all the substrates are substrates with a metal layer of a plastic film, and all the substrates are substrates with a metal layer of a fabric It may be a combination of a substrate with a metal layer based on a plastic film and a substrate with a metal layer based on a fabric such as a glass fiber woven fabric.

  The reflector as described above has a role as a reflector of radiant heat. Therefore, by sandwiching the thermal energy consuming layer (F) with the reflective material, thermal energy can be effectively attenuated based on the thermal energy consuming layer, that is, the silica-based inorganic fiber. That is, in the laminated unit in which the reflective material is laminated on both sides of the silica-based inorganic fiber nonwoven fabric, the thermal energy consumption layer becomes a closed space, and the temperature rises in the silica-based inorganic fiber nonwoven fabric constituting the thermal energy consumption layer, Then, it makes it easy to start the dehydration condensation reaction of said Formula (1). And the water | moisture content produced | generated by dehydration condensation will be vaporized by further temperature rise, since spreading | diffusion is suppressed by a reflecting material. Thus, the heat energy transmitted from the heat source is consumed, and as a result, not only the heat insulation effect obtained according to the thickness of the non-woven fabric made of silica fiber but also the heat energy attenuation effect due to vaporization heat can be obtained. Temperature reduction can be achieved.

(3) Graphite layer (G)
As a graphite layer to be a component of the laminate type heat insulator, a graphite sheet having a graphite content of 80 to 100% by weight, preferably 90 to 100% by weight is used, in which graphite crystals are oriented in the plane direction.

  As such a graphite sheet, an expanded graphite sheet which can be made into a sheet by rolling and forming expanded graphite, or a polymer film such as an aromatic polyimide sheet under a reducing atmosphere and pressure. A polymer-type graphite sheet which can be obtained by heat treatment to graphitization to over 2500 ° C. can also be used. From the viewpoint of heat resistance, an expanded graphite sheet is preferably used.

Expanded graphite is, for example, graphite powder such as natural scaly graphite, pyrolytic graphite, kish graphite, etc., inorganic acid such as sulfuric acid or nitric acid, and strongly oxidized such as concentrated nitric acid, perchloric acid, dichromate, hydrogen peroxide or the like The compound is treated with an agent to form a graphite intercalation compound, washed with water, dried, and rapidly heated to 1000 ° C. or more to gasify the intercalation compound, and the graphite layer is pushed up and the volume expands to about several hundred times Can be manufactured by
The expanded graphite sheet usually has a thickness of about 10 μm to 3 mm, preferably 50 μm to 1 mm, though depending on the production method. Further, the heat resistant temperature is over 1000 ° C. in a short time, and is about 500 ° C. because it is oxidized and consumed in a long time. This expanded graphite sheet has the graphite layers pushed apart, is excellent in flexibility, and is excellent in heat resistance.

  Further, in the polymer type graphite sheet, the thickness is 20 to 100 μm, preferably 25 to 75 μm, and the heat resistant temperature is usually about 400 to 800 ° C. although it depends on the starting material, the manufacturing method and the like.

Since such a graphite sheet is excellent in the anisotropy of heat conduction, for example, when a part of the fireproof insulation sheet has a flame, heat is conducted to the entire sheet surface to locally raise the temperature. It is possible to suppress the damage of the layers constituting the laminated type heat insulator.
Furthermore, when using an expanded graphite sheet as a graphite sheet, the heat insulation effect based on the space between layers can also be obtained.

In order to effectively obtain the temperature rise suppression effect and the layer damage alleviation effect by the anisotropic effect of the heat conduction of the graphite sheet, “Reflector / graphite layer / reflection with a heat-radiating reflector laminated on both sides” It is preferable to use in the lamination | stacking unit of material.
When an expanded graphite sheet is used, a heat insulating effect can be obtained in proportion to the number of sheets, so it is preferable to stack a plurality of sheets according to the specification of the heat insulating sheet. In the case of laminating a plurality of sheets, the graphite sheets may be laminated, or may be laminated in a separated state with a metal layer, a nonwoven fabric made of silica-based inorganic fiber, or the like interposed.

  In addition, the graphite layer is preferably a laminated unit combined with a heat energy consuming layer (nonwoven fabric made of silica based inorganic fibers), that is, a "graphite layer / heat energy consuming layer", preferably "reflecting material / graphite layer / heat energy consuming layer / Used as a reflector. By using the laminated unit of “reflector / graphite layer / thermal energy consumption layer / reflector” so that the graphite layer is closer to the heat source, the graphite layer can be used even if it is locally heated. It is thermally conducted over the entire surface, and the thermal energy can be conducted uniformly to the entire silica-based inorganic fiber non-woven fabric constituting the thermal energy consuming layer. As a result, thermal energy is uniformly applied to the non-woven fabric made of silica-based inorganic fibers, and a dehydration condensation reaction can be caused throughout the non-woven fabric. As a result, thermal energy can be efficiently consumed, and an excellent temperature reduction effect can be obtained.

(4) Airgel-Supporting Sheet The airgel-supporting sheet is a sheet-like fiber mass as a supporting body, in which a silica airgel having a porosity of 70% or more, preferably 80% or more, is impregnated and carried.

  The sheet-like fiber mass serving as a support of silica airgel is glass fiber; ceramic fiber such as silica fiber, alumina fiber, titania fiber, silicon carbide fiber, etc .; metal fiber; artificial mineral fiber such as rock wool, basart fiber; carbon fiber A whisker or the like may be made into a paper or board shape by a paper-making method, or a sheet-like molding such as a non-woven fabric, a mat, a felt or the like formed into a sheet by adding a binder as appropriate. Among these, in order to effectively obtain the heat insulation effect of the silica airgel, it is desirable that the shape as the support can be maintained even at the heat resistance temperature (about 750 ° C.) of the silica airgel. From such a point of view and cost, preferably, a sheet of artificial mineral fiber, particularly rock wool is preferably used.

The silica airgel to be supported has nano-sized pores having a porosity of 70% by volume or more, preferably 80% by volume or more, more preferably 90% by volume or more, particle size 50 nm to 5 mm, porosity 90% or more The gel particles have a particle diameter in the range of 1 μm to 5 mm, more preferably in the range of 1 μm to 500 μm, and still more preferably in the range of 5 μm to 400 μm. Such an airgel is very light with a bulk density of about 0.1 to 0.4 g / cm ³ .

The silica airgel may be simply impregnated and dispersed in the sheet-like fiber mass, or may be supported on the constituent fibers of the sheet-like fiber mass using a binder or the like.
It is preferable that the content ratio (weight ratio) of the sheet-like fiber lump which is a support body and a silica airgel is 9: 1-5: 5, More preferably, it is 8: 2-6: 4.

As such an airgel support sheet, for example, when using a sheet of rock wool as a support, various binders are added by using a mixture of rock wool and airgel (silica aerogel) subjected to de-shot as a main raw material. It can manufacture by shape | molding in a sheet form.
Such an airgel-carrying sheet usually has a thermal conductivity of 0.028 W / mK or less, preferably about 0.013 W / mK to about 0.025 W / mK.

  The thickness of the airgel carrier sheet is usually 2 to 20 mm, preferably 3 to 15 mm, more preferably 3 to 5 mm. From the viewpoint of light weight, thinness and flexibility, it is preferable to be thin. However, if the carrier is too thin, the amount of aerogel to be carried becomes small, and as a result, it becomes difficult to obtain sufficient heat insulation.

The airgel-supporting sheet is superior in heat insulation to non-woven fabrics and mats of the same thickness on which the airgel is not supported, since the heat insulation effect of the airgel-based holes is obtained in addition to the holes based on the support. However, since the airgel carrier sheet is thicker than the other layers as described above, the number of layers included in the laminate is in accordance with the specification and usage of the heat insulator from the viewpoint of thinning the heat insulator. And will be selected accordingly.
In addition, the airgel-carrying sheet exhibits excellent thermal insulation due to the convection in the pores and the low thermal conductivity. However, since the heat resistance of the silica airgel itself is about 750 ° C. and the heat energy consumption function is small, the heat energy consumption layer has a small effect of preventing damage due to heating of the layers constituting the laminate type heat insulator. It is preferable to laminately arrange at a position farther from the heat source than the graphite layer.

(5) Other layers As the layers constituting the fireproof thermal insulation sheet, other than above, if desired, glass fibers made of high heat resistance temperature within the allowable range of thickness, ceramic fibers such as silica fibers and alumina fibers A cloth such as a woven or non-woven fabric may be provided.

[Layer configuration of laminated type heat insulator]
Next, the layer configuration of the laminated type heat insulator will be described.
The laminate type heat insulator constituting the main body of the fireproof heat insulation sheet of the present invention comprises the above-mentioned heat energy consuming layer (silica fiber non-woven fabric), reflector (metal foil and / or substrate with metal layer), graphite layer, It is a laminated body which laminated | stacked the airgel carrier sheet. The number of layers and the stacking order are not particularly limited, but in terms of the role of each layer, it is preferable that the layers be arranged based on the following.

The heat energy consuming layer and the reflective material are preferably used as a lamination unit.
The graphite layer is preferably used as a "graphite layer / thermal energy consuming layer", preferably as a "reflecting material / graphite layer / thermal energy consuming layer / reflecting material".
The graphite layer is preferably stacked on the heat source side from the middle position in the thickness direction of the stacked type heat insulator.
When the airgel support sheet is included, the graphite layer is preferably laminated on the side opposite to the heat source (the side farther from the heat source) than the heat energy consuming layer. Preferably, at least one heat energy consuming layer is disposed between the graphite layer and the airgel sheet.
-The metal foil constituting the reflective material and the substrate with a metal layer may be incorporated alone as a constituent layer of a laminate type heat insulator, or may be incorporated as a laminate unit in which a plurality of metal foils are laminated. And the metal foil and the base material with a metal layer may be integrated as a unit.
-It is preferable that the outermost surface of at least one side of the laminated type heat insulator is made of a reflective material. The metal layer that composes the reflector can reflect thermal energy, but it also has high thermal conductivity in the surface direction, so when it is locally heated, heat is applied in the layer surface direction of the laminated type heat insulator, similar to the graphite layer. Conduction can mitigate local damage. In this respect, since the graphite layer does not have a reflective function, if it is disposed close to the heat source, the graphite layer may be damaged before sufficiently exerting the planar energy diffusion effect.
・ The heat insulation performance generally increases as the number of laminated layers increases, but an increase in the number of layers causes an increase in the thickness and weight of the fireproof thermal insulation sheet, so the thickness, weight, and heat resistance required of each layer Depending, according to the above it is possible to select appropriately.

  From the above viewpoints, as a non-woven fabric (F), a reflector (R), a graphite sheet (G), and an airgel support sheet (A), as an example of the layer configuration of the laminate, from the heat source side, "R / G / F / R It is preferable to include at least the stacked unit of “R / F / R / A”, “R / F / R / A / R” or “R / G / F / R / A” from the heat source side. .

Therefore, although "R / G / F / R / A" is the thinnest and it is considered possible to obtain the temperature reduction effect efficiently, in order to obtain a further temperature reduction effect, for example, "R / F "R" / "R" lamination unit is appropriately interposed (for example, "R / G / F / R / F / R / A"), and a plurality of graphite layers are laminated on the side close to the heat source (for example, "R / G / G / F / R / A ") or" R / G / F / R "stacked units are interposed in a repeating unit (eg" R / G / F / R / G / F / R / A ") or close to the surface On the side, a plurality of airgel support sheets may be contained (for example, "R / G / F / R / A / R / A") or a plurality of lamination units of "R / F / R / A" may be intervened as a repeating unit ( For example, “R / G / F / R / F / R / A / R / F / R / A”) makes the temperature lower Effect can be to give efficient.
Also, the reflector (R) may be composed of only one of the metal foil (M) and the substrate with a metal layer (MD), but the role as a reflector due to combustion disappears, and the shape maintenance of the heat insulator From the point of view, it may be used as “M / M” in relation to “M / MD” unit or thickness.

  The laminated type heat insulator having the above configuration is used such that the side closest to the heat source is the reflector. Furthermore, in the relationship between the graphite layer and the thermal energy consuming layer, the graphite layer is used so as to be closer to the heat source. When the airgel support sheet is included, the heat energy consuming layer and the graphite layer are used so as to be closer to the heat source. Thereby, even if the heat source and the flame are in a state of being locally heated by a part of the laminated type heat insulator, the heat conduction to the entire surface of the fireproof heat insulating sheet is suppressed to locally heat and burn. Furthermore, after the entire surface is heated through the graphite layer, the silica-based inorganic fiber non-woven fabric which is the adjacent heat energy consuming layer is heated. When the temperature rises by heating, the silica-based inorganic fiber having a hydroxyl group undergoes a dehydration condensation reaction to form water. The generated water diffuses in the non-woven fabric, but the metal layer constituting the reflector prevents the further diffusion and evaporates using the heat energy in the non-woven fabric. The temperature of the reflective material in contact with the non-woven fabric rises with the heating of the non-woven fabric, but the heat energy is the temperature of the airgel support sheet opposite to the heating source due to the heat insulating effect of the airgel contained in the airgel support sheet. Will lower the

<Bag body>
The laminated type heat insulator having the above configuration is housed in a bag made of fireproof fiber woven fabric.
Here, the fire resistant fiber is a fiber having a heat resistance of 900 ° C. or more, preferably 1000 ° C. or more. Specifically, a bag made of a woven fabric of glass fibers, silica fibers or ceramic fibers, preferably a woven fabric of silica fibers, having an alumina content of 20% or more is used.

  Although the thickness of the fire-resistant fiber woven fabric varies depending on the type of woven fabric (the type of fibers constituting the woven fabric), the woven fabric is directly exposed to a heat source, so As a storage bag, it is necessary to have heat resistance that does not collapse even if exposed to heating for 1 hour or more, and from such a viewpoint, in the case of a woven fabric made of silica fiber (silica cloth), thickness 0.2 to 1.3 mm It is preferable to set it as a degree. The silica cloth having a thickness of about 0.2 to 1.3 mm has a heat resistant temperature of about 900 to 1100 ° C.

<Fireproof insulation sheet>
The fireproof thermal insulation sheet 10 shown in FIG. 1 is obtained by housing and sealing a laminated type heat insulator 2 in a bag 1 of silica cloth. In such a configuration, it is possible to ease the requirement for fixing the laminated state of the laminated type heat insulator 2. That is, in the bonding using an adhesive having a low heat resistance temperature, carbonization occurs due to high temperature deterioration, and there is a possibility that the stability of the laminated state can not be secured. As long as thermal degradation that may damage the bag 1 does not occur, the laminated state of the internal laminate can be stably maintained. That is, it is convenient because the multi-layered fireproof insulation sheet can be handled integrally.

Moreover, since it can be bend | folded and folded as a fireproof heat insulation sheet | seat of 1 sheet by achieving thickness reduction as a lamination | stacking type heat insulator, versatility as a construction site of fire prevention measures is high. Since it can be handled like a thick cloth, it is possible to wrap around a curved surface structure other than a flat plate or a tray of a rectangular solid or the like.
Moreover, attachment construction can be performed using fasteners, such as a rivet, a screw, nail, a clip, a binding band, and a wire.

FIG. 2 shows the case where a fireproof and heat insulating sheet 12 using a split type bag body 11 having a plurality of storage parts 11a divided by the division part 3 is applied to the encapsulation of a box 5 containing cables. . Such a fireproof heat insulating sheet 12 is also coated on the equipment housed in the box 5 having the corner so that the division 3 is the corner, thereby forming a laminate which is a fireproof heat insulating sheet. It becomes possible to package easily, without bending. This can reduce the mechanical load on the laminated insulation of the fireproof insulation sheet.
In FIG. 2, the fireproof and heat shielding sheet 12 is attached and fixed to the box 5 by the rivet 4.

[Preparation of fireproof insulation sheet]
The following were used as components of the fireproof insulation sheet.
(1) Thermal energy consumption layer (F)
belChem's belCotex (registered trademark) 110 (composition is AlO _1.5 · 18 [(SiO ₂ ) _0.6 (SiO _1.5 OH) _0.4 ]), a silica fiber non-woven fabric with a fiber diameter of 9 μm (thickness 5.1 mm, bulk density 0. 15 g / cm ³ ) was used.

(2) Reflective material (R)
The following aluminum foil (M) or a substrate with an aluminum layer (MD) was used.
(2-1) Aluminum foil (M)
An aluminum foil having a thickness of 0.02 mm and a density of 1.95 g / cm ³ was used.
(2-2) Substrate with Al layer (MD)
The following two types of Al-deposited woven fabrics (MD ₁ , MD ₂ ) were used in which aluminum was deposited on both sides of glass fiber woven fabrics having different thicknesses.
Was used.
MD ₁ : Thickness 0.4 mm, bulk density 1.29 g / cm ³
MD ₂ : thickness 0.1 mm, bulk density 1.40 g / cm ³

(3) Graphite layer (G)
An expanded graphite sheet ("Cavofit" (registered trademark) of Hitachi Chemical Co., Ltd.) was used. This has a thickness of 0.4 mm and a bulk density of 1.02 g / cm ³ .

(4) Aerogel support sheet (A)
The rock wool from which the fiber particles were removed and the silica airgel (porosity 90%) were mixed in water at a ratio of rock wool (support): silica airgel = 7: 3 to obtain an aqueous dispersion of the mixture. A binder and glass fiber were added to this, and papermaking was carried out to produce an airgel carrying sheet. The composition of the obtained airgel carrier sheet is 57.6% by weight of rock wool, 24.6% by weight of silica airgel, 10% by weight of glass fiber, and 4.8% by weight of binder. Moreover, the obtained airgel support sheet has a thickness of 3.8 mm and a bulk density of 0.19 g / cm ³ .

(5) Bag body (SB)
A bag body having a thickness of 0.8 mm and a bulk density of 0.93 g / cm ³ and formed of a heat resistant glass cloth manufactured by Unitika Co., Ltd. was used. This heat-resistant glass cloth is a woven fabric of high silicate glass fibers having a SiO ₂ content of 96% or more, and also has heat resistance to heating at 945 ° C. for one hour.

[Confirmation of generated water in heat energy consuming layer]
A bag laminated type heat insulating material having a laminated structure of _{M 1 / F 1 / M 2} / M 3 / F 2 / M 4 / M 5 / F 3 / M 7 / M 8 / F 4 / M 9 / MD It stored and sealed and the fireproof insulation sheet was produced. By bringing one side (M ₁ side) of the fireproof insulation sheet into contact with the heating furnace, _one side of the fireproof insulation sheet was heated according to the ISO 834 standard heating curve. At 43 minutes after the start of heating (in-furnace temperature: about 900 ° C.), the fireproof insulation sheet was taken out of the heating furnace. The changes of the heating temperature and the surface temperature (measured by the thermocouple) of the non-heated side of the fireproof insulation sheet are as shown in FIG. The surface temperature on the side opposite to the heat source 43 minutes after the start of heating was about 80 ° C

The bag body of the fireproof insulation sheet taken out was opened, and the laminate was taken out and observed. The silica-based inorganic fiber non-woven fabric (F ₄ ) and the reflector (aluminum foil M ₉ , aluminum-deposited woven fabric MD) located farthest from the heat source were wet, and water droplets could be confirmed.
Therefore, in the refractory thermal insulation sheet of the present invention, the silica-based inorganic fiber non-woven fabric has thermal energy due to the heat of vaporization of water generated by the dehydration condensation reaction of the silica-based inorganic fiber in addition to the heat insulating effect proportional to the thickness of the non-woven fabric. A damping effect is obtained, which is considered to suppress temperature rise.

[Fireproof insulation sheet No. Evaluation of 1 to 5]
A 30 cm × 30 cm laminate type heat insulator having a laminate configuration as shown in Table 1 was housed in a bag and sealed, and a fireproof heat insulation sheet No. 1 was prepared. 1 to 5 were made. The thickness and weight of each fireproof insulation sheet are as shown in Table 1.

  The fireproof thermal insulation sheet No. 1 produced above. 1 to No. The combustion evaluation test was conducted for No.5. In the combustion evaluation test, as shown in FIG. 4, heating was performed for 1 hour with the flame 21 applied to the central portion of the fireproof insulation sheet 20. A thermocouple 22 was attached to the surface opposite to the flamed side of the fireproof insulation sheet 20 (back side), and the temperature change on the back side during heating was measured and recorded. The temperature on the back side after one hour of heating is shown in Table 1.

Moreover, after the combustion test, the bag was opened and the state of each layer of the laminated type heat insulator was observed. Results of counting the number of layers in which damage such as formation of holes in the sheet (layer) or deterioration due to combustion or loss of shape of the sheet was observed (number of damaged layers) are also shown in Table 1.
Moreover, fireproof insulation sheet No. 1 and No. The measurement result (graph) of back surface temperature 2 is shown in FIG.
Moreover, fireproof insulation sheet No. 2, No. Photographs showing the state of layers after the combustion test of No. 4 are shown in FIGS. 6 and 7, respectively.

  No. No. 2 fireproof insulation sheet No. As compared with 1, a laminated type heat insulator in which two graphite sheets are interposed on the heat source side is used. By interposing the graphite layer, the surface temperature after the combustion test can be lowered by as much as 10 ° C., and the number of layers damaged by combustion is as low as 11 layers. It is considered that the thermal conductivity of the graphite layer in the surface direction with respect to the local heating alleviated the temperature rise of the entire laminate and the damage of the constituent layers of the laminate type heat insulator.

  No. The fireproof thermal insulation sheet of 3 interposes the airgel carrier sheet instead of the graphite sheet at a position (rear side) farther from the heat source than the middle of the laminate type thermal insulator. No. Although the back surface temperature was lowered by 20 ° C. or more compared to 1 and showed an excellent heat insulating effect, it became thick as a fireproof heat insulating sheet, and the effect of reducing the number of damaged layers was not obtained. Since the airgel support sheet is disposed in the 12th layer from the heat source, it is considered that the reduction effect on the number of damaged sheets is limited or can not be exhibited.

  No. Graph No. 4 arranges a graphite sheet in the outermost layer on the burning side of the laminate type heat insulator, and laminates an airgel carrier sheet in the middle part. No. 1 as a heat insulator. 1, No. The temperature reduction effect is no. It is only 3 ° C. lower than 1 and the number of damaged layers is No. 1 It was more than one. Since the surface closest to the heat source of the heat insulation sheet was a graphite sheet, the graphite sheet was damaged, and the heat conduction effect of the graphite sheet could not be sufficiently exhibited. Moreover, since the layer adjacent to a graphite sheet was metal foil, it is considered that the heat diffusion effect of the surface direction by a graphite sheet was not able to be exhibited. Therefore, it can be said that the thermal diffusion effect in the surface direction by the graphite sheet is easily obtained when in contact with the thermal energy consuming layer.

  No. No. 5 has two layers of graphite sheet, one layer of aerogel, and two layers of thermal energy consumption layer. The back surface temperature is about the same as that of No. 1, but the number of damaged layers is No. 1 It was less than one. A reflective material is disposed in the outermost layer on the heat source side, and a laminate unit of “G / F” is further disposed so that the graphite layer is on the heat source side, and a thermal energy consumption layer is provided between the airgel support sheet and the graphite layer. It can be seen that by stacking and arranging, the number of damaged layers can be reduced efficiently and the temperature reduction effect on thickness can be enhanced.

  Although the fireproof insulation sheet of the present invention is thin and lightweight, when it is locally heated, the heat energy is uniformly conducted to the whole of the fireproof insulation sheet and the heat energy is utilized to utilize the heat of vaporization. Since the temperature rise is efficiently suppressed and the damage due to the combustion of the laminated type heat insulator is suppressed by attenuating it, it is used as a fireproof insulation sheet used for fireproof insulation of places such as encapsulation of cable bundle and corner parts. It is useful. Therefore, according to the space to be constructed, by appropriately selecting and designing the layer configuration of the laminated type heat insulator, it can be used for efficient fire prevention measures even at a place having a space restriction.

Reference Signs List 1 bag body 2 laminated type heat insulator 3 split portion 4 fixture 10, 20 fireproof heat insulating sheet 11 split type bag body 12 split type fire resistant heat insulating sheet

Claims (9)

It is a fireproof thermal insulation sheet in which a laminate type heat insulator is housed in a bag body formed of fireproof fiber woven fabric, wherein the laminate type heat insulator is
At least one heat energy consuming layer composed of a non-woven fabric of silica-based inorganic fibers having a hydroxyl group;
Laminated body in which at least one layer of at least one layer of a graphite layer in which graphite crystals are oriented in the surface direction is used. Fireproof insulation sheet.   The fireproof thermal insulation sheet according to claim 1, further comprising: a lamination unit in which the graphite layer is laminated on one side of the thermal energy consuming layer.   The fireproof insulation sheet according to claim 1 or 2 including a lamination unit by which said reflector was laminated on both sides of said heat energy consumption layer.   The fireproof insulation sheet according to claim 1, wherein the laminated type heat insulator includes a laminated unit in which a reflector, a graphite layer, a heat energy consuming layer, and a reflector are laminated in this order.   The fireproof heat insulation sheet according to any one of claims 1 to 4, wherein the laminated type heat insulation body further includes an airgel support sheet in which a silica airgel having a porosity of 70% or more is supported on a sheet-like fiber mass.   The fireproof insulation sheet according to claim 5, wherein at least one energy consumption layer is disposed between the graphite layer and the airgel support sheet.   The fireproof insulation sheet according to any one of claims 1 to 6, wherein the outermost surface of at least one of the laminated type heat insulators is the reflective material.   The fireproof insulation sheet according to any one of claims 1 to 7, wherein the graphite layer is an expanded graphite sheet.   The metal-deposited fabric according to any one of claims 1 to 8, wherein the metal layer-attached substrate is a glass-fiber, a silica-fiber, a ceramic fiber, or a fabric obtained by knitting and weaving a mineral fiber. Fireproof insulation sheet as described in.