JP2001105517A - Thermally expansible fire-resistant sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermally expansible fire-resistant sheet excellent in handling properties by imparting strength to a sheet containing non-combustible fibers and thermally expansible inorganic matter without damaging the fire- resistant heat insulating properties or fore spreading resistance thereof. SOLUTION: A thermally expansible fire-resistant sheet is formed from a laminate wherein a base material layer comprising a resin composition (I) containing thermally expansible inorganic matter and a resin component is laminated on at least the single surface of a sheet molded object consisting of 20-95 wt.% of non-combustible fibers and 80-5 wt.% of the thermally expansible inorganic matter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-expandable fire-resistant sheet suitably used for a fire-resistant joint material, a fire-resistant cable, a fire-resistant covering material, and the like used for fire prevention and fire-resistant buildings.

[0002]

2. Description of the Related Art At present, various heat-expandable refractory materials have been developed as thin and light refractory materials. Among them, as a mat-like sheet containing non-combustible fibers and a thermally expandable inorganic substance, for example, "Techno Fire" (trade name) manufactured by Technical Fiber Products Co., Ltd., and a flame-retardant molding material described in JP-A-8-67771 And the like. Each of the above mat-shaped sheets is a material excellent in fire spread resistance since the main constituent material is a non-combustible material.

[0003] However, the above-mentioned mat-like sheet has a problem that it is easily broken at the time of handling since the sheet shape is mainly maintained by entanglement of incombustible fibers.

[0004]

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a sheet containing a non-combustible fiber and a heat-expandable inorganic material, without impairing the fire-insulating property and the fire-spreading property of the sheet. Accordingly, it is an object of the present invention to provide a heat-expandable refractory sheet excellent in handleability.

[0005]

The heat-expandable refractory sheet of the invention according to claim 1 (hereinafter referred to as the first invention) has a non-combustible fiber having an average fiber diameter of 1 to 10 μm and an average fiber length of 5 to 50 mm. 95% by weight and 80-5% by weight of thermally expandable inorganic substance
A heat-expandable fire-resistant sheet comprising a base material layer made of a resin composition (I) containing a heat-expandable inorganic substance and a resin component laminated on at least one surface of a sheet molded body comprising:
The base material layer composed of the resin composition (I) has an oxygen index (JI
(Measured according to SK 7201) of 25 or more.

The heat-expandable refractory sheet of the invention according to claim 2 (hereinafter referred to as the second invention) has an average fiber diameter of 1 to 10 μm.
m, at least one surface of a sheet molded body comprising 20 to 95% by weight of noncombustible fibers having an average fiber length of 5 to 50 mm and 80 to 5% by weight of a thermally expandable inorganic material contains a phosphorus compound, a hydroxyl group-containing hydrocarbon and a resin component. A heat-expandable refractory sheet in which a base material layer made of the resin composition (II) is laminated, wherein the base material layer made of the resin composition (II) is measured according to an oxygen index (measured in accordance with JIS K 7201). ) Having a flame retardancy of 25 or more.

Hereinafter, the first invention will be described in detail. The heat-expandable refractory sheet of the first invention is formed from a laminate in which a base material layer made of a resin composition (I) is laminated on at least one surface of a sheet molded body made of non-combustible fibers and a heat-expandable inorganic substance. .

[0008] The sheet molding is formed from a mixture of non-combustible fibers and a thermally expandable inorganic substance. The non-combustible fibers are preferably those having a function of supporting a thermally expandable inorganic material between the fibers while maintaining the mat-like sheet shape by the fibers being entangled, for example, ceramic fibers, glass fibers, glass wool fibers, Carbon fibers, rock wool fibers, and the like are included. These may be used alone or in combination of two or more.

As the shape of the noncombustible fibers, those having an average fiber diameter of 1 to 10 μm and an average fiber length of 5 to 50 mm are used. If the average fiber diameter is less than 1 μm, there is a risk of adverse effects on the human body and deterioration of the manufacturing environment, and if it exceeds 10 μm, the entanglement of the fibers becomes insufficient, so that it is difficult to form a sheet. If the average fiber length is less than 5 mm, the entanglement of the fibers becomes insufficient, so that it is difficult to form a sheet shape. If the average fiber length exceeds 50 mm, mixing with the thermally expandable inorganic material becomes difficult, and the dispersibility decreases.

As the above-mentioned thermally expandable inorganic substance, an acid,
A layered inorganic compound in which water or the like is chemically stably retained is preferable. Such a heat-expandable inorganic substance is a compound that expands physically when heated, e.g., an acid or water held between layers evaporates and the interlayer distance is expanded, and for example, vermiculite (thermal Expansion start temperature: 26
0 ° C.) and neutralized heat-expandable graphite (thermal expansion start temperature: 200 ° C.).

In order to maintain the sheet shape by entanglement of the non-combustible fibers and to support the heat-expandable inorganic material between the fibers, the proportion of the non-combustible fibers in the sheet molding is required to be 20 to 95% by weight. is there.

[0012] In order to maintain the sheet shape of the sheet molded body, a resin binder may be added. The amount of the resin binder to be added is preferably less than 5% by weight, because if the amount increases, the fire resistance of the sheet molded body decreases. The resin binder is not particularly limited as long as the temperature at the time of melting and molding does not exceed the expansion temperature of the thermally expandable inorganic substance. For example, in the case of using neutralized heat-expandable graphite as the heat-expandable inorganic substance, a thermoplastic resin such as polyethylene or butyl rubber having a softening point of 200 ° C. or less, and a curing temperature of 20 ° C.
It is preferable to use a thermosetting liquid resin such as an epoxy resin or a phenol resin at 0 ° C. or lower as the resin binder.

The neutralized heat-expandable graphite is obtained by neutralizing a conventionally known heat-expandable graphite. The heat-expandable graphite is a natural scale-like graphite, pyrolytic graphite, powder such as quiche graphite,
Produced by treating with inorganic acids such as concentrated sulfuric acid, nitric acid and selenic acid and strong oxidizing agents such as concentrated nitric acid, perchloric acid, perchlorate, permanganate, dichromate, hydrogen peroxide, etc. Is a crystalline intercalation compound that maintains the layered structure of carbon.

The heat-expandable graphite obtained by the acid treatment as described above is further neutralized with ammonia, an aliphatic lower amine, an alkali metal compound, an alkaline earth metal compound, etc. Heat-expandable graphite is obtained.

The aliphatic lower amine is not particularly restricted but includes, for example, monomethylamine, dimethylamine, trimethylamine, ethylamine, propylamine, butylamine and the like.

The above alkali metal compound and alkaline earth metal compound are not particularly restricted but include, for example, hydroxides, oxides, carbonates, sulfates, organic acid salts of potassium, sodium, calcium, barium, magnesium and the like. Is mentioned.

The particle size of the neutralized heat-expandable graphite is preferably 20 to 200 mesh. Particle size is 200
If it is smaller than the mesh, the degree of expansion of the graphite is small, and a predetermined refractory and heat-insulating layer cannot be obtained.If it is larger than 20 mesh, there is an advantage that the degree of expansion of the graphite is large. Deterioration of properties and deterioration of physical properties are inevitable.

Commercially available neutralized heat-expandable graphite is, for example, “Frame Cut GRE” manufactured by Tosoh Corporation.
P-EG "," GRAFG "manufactured by UCAR Carbon
UARD # 160 ”,“ GRAFGUARD # 220 ”
And the like.

Commercial products of the above vermiculite include:
For example, "Vermiculite" manufactured by Kinsei Matech Co., Ltd. may be mentioned.

The thickness of the sheet molding is 0.1 to 5 m.
m is preferred.

As a method for producing the above-mentioned molded sheet, a method of mixing non-combustible fibers and a heat-expandable inorganic substance in water or an organic solvent, spreading the resulting slurry-like mixture into a sheet, and drying the mixture; A fiber, a thermally expandable inorganic substance, and a thermosetting liquid resin binder (for example, a resol-type phenol resin, an epoxy resin, etc.) are mixed, and the obtained mixture is spread into a sheet and heated and pressed to harden the binder resin to form a sheet. And the like.

Examples of commercially available sheet molded products include "Techno Fire" (trade name) manufactured by Technical Fiber Products.

Resin composition (I) used for the above base layer
Contains a thermally expandable inorganic substance and a resin component. Since the base material layer has a thermal expansion performance to improve fire insulation performance, and has a flame retardant property, the strength of a sheet molded body can be improved without lowering fire spread resistance. It has the function of improving the handling of the intumescent refractory sheet. Therefore, when the thickness of the base material layer is small, the strength of the sheet molded body cannot be sufficiently improved, and when the thickness is large, the fire spread resistance decreases.
mm is preferred.

As the thermally expandable inorganic substance in the resin composition (I), the same one as the above-mentioned sheet molding is used. The thermally expandable inorganic substance may be used alone, or two or more kinds may be used in combination. Further, the resin component in the resin composition (I) is a resin component that can be formed into a sheet or a film, and the temperature at the time of melt molding does not exceed the thermal expansion start temperature of the thermally expandable inorganic substance. The resin binder is not particularly limited, and examples thereof include the resin binder.

The content of the thermally expandable inorganic substance in the resin composition (I) is preferably from 5 to 85% by weight. When the content is less than 5% by weight, the expansion ratio becomes small, and the fire insulating performance becomes insufficient. When the content exceeds 85% by weight, the tensile strength and elongation exhibiting the reinforcing effect decrease.

The content of the resin component in the resin composition (I) is preferably 15 to 60% by weight. Content is 1
If the amount is less than 5% by weight, the elongation at break of the substrate layer is sharply reduced, and the handleability is deteriorated. If it exceeds 60% by weight, the flame retardancy is reduced.

The base material layer has flame retardancy from the viewpoint of fire spread resistance, and is limited to an oxygen index of 25 or more. The oxygen index is a value measured according to JIS K7201.

Examples of the method for imparting the above-mentioned flame retardancy of the oxygen index include, for example, a bromine compound such as decabromodiphenyl ether; a water-containing inorganic substance such as aluminum hydroxide and magnesium hydroxide; Compound: a method of adding a flame retardant such as a phosphorus compound such as ammonium polyphosphate and red phosphorus. The flame retardants may be used alone or in combination of two or more. In the case where neutralized heat-expandable graphite is used as the heat-expandable inorganic substance, the heat-expandable graphite itself functions as a flame retardant, so that it is not necessary to add a flame retardant separately.

In order to improve the flame retardancy and increase the amount of the base material layer,
An inorganic filler may be added to the resin composition (I). The inorganic filler is not particularly limited as long as it is a non-combustible inorganic substance and has an effect of increasing the amount.For example, calcium carbonate, magnesium carbonate, talc, mica, fly ash, aluminum hydroxide, magnesium hydroxide, silica , Alumina and the like. These may be used alone or in combination of two or more.

If necessary, additives such as an antioxidant, a metal harm inhibitor, an antistatic agent, a stabilizer, a crosslinking agent, a lubricant, a softener, and a pigment may be added to the base material layer. Good.

When a sheet-like base material layer is produced from the resin composition (I), a method for forming a sheet or film of a thermoplastic resin is used.

As a method of laminating the above-mentioned base material layer and the above-mentioned sheet molding, a method of heating and melting a sheet-like base material layer and press-bonding the same; a resin composition (I) constituting the base material layer with a solvent; A method of diluting and dissolving into a paint, coating and drying a sheet molded body; a method of laminating a sheet-shaped base layer and a sheet molded body using an adhesive; And a method of stacking by utilizing.

In the above-mentioned laminating method, since the resin composition (I) permeates between the fibers of the sheet molded body, an anchor effect is exhibited, and the adhesion at the interface between the base material layer and the sheet molded body is improved. preferable.

It is preferable that the base material layer has tackiness, because it becomes possible to temporarily adhere to the material for coating or laminating the heat-expandable refractory sheet, and the workability of coating or laminating is greatly improved.

The self-adhesive substrate layer can be formed from a self-adhesive resin component such as butyl rubber and polybutene, and a tackifier. As a method for imparting adhesiveness to a substrate layer having no self-adhesiveness or having insufficient self-adhesiveness, for example, as used in a general adhesive tape manufacturing method, A method of applying a pressure-sensitive adhesive to the material layer may be used.

As the tackifier, a tackifier resin,
Examples include plasticizers, fats and oils, and low-polymerized polymers.

When the resin component contained in the base layer is a liquid thermosetting resin such as a resol-type phenol resin or an epoxy resin, the thermosetting resin is previously applied to the sheet molding before the base layer is thermoset. It is also possible to apply a resin and then heat cure. Also in this case, since the resin permeates between the fibers, an anchor effect is exhibited, and thus the adhesion at the interface between the base material layer and the sheet molded body is improved.

Next, the second invention will be described. The heat-expandable refractory sheet of the second invention is formed from a laminate in which a base material layer made of a resin composition (II) is laminated on at least one surface of a sheet molded product made of noncombustible fibers and a heat-expandable inorganic substance. .

As the above-mentioned sheet molding, the same sheet molding as in the first invention is used.

Resin composition (II) used for the above base layer
Contains a phosphorus compound, a hydroxyl group-containing hydrocarbon and a resin component. As the resin component, the same resin component as in the first invention is used. As the phosphorus compound, for example,
Red phosphorus, phosphates, metal phosphates and the like can be mentioned. Examples of the hydroxyl group-containing hydrocarbon include glycols, pentaerythritols, starches, celluloses, polysaccharides and the like, and these may be used alone or in combination of two or more. Among these, pentaerythritols are particularly preferable because of their high carbonization promoting effect.

The total content of the phosphorus compound and the hydroxyl group-containing hydrocarbon in the resin composition (II) is preferably from 30 to 85% by weight. If the total content is less than 35% by weight, the fire spread resistance becomes insufficient, and if it exceeds 85% by weight, the elongation at break sharply decreases, and the handleability deteriorates. The weight ratio of the phosphorus compound to the hydroxyl group-containing hydrocarbon (hydroxyl group-containing hydrocarbon / phosphorus compound) is preferably 0.05 to 20 in order to foam and carbonize to form a sufficient refractory heat-insulating layer.

The resin composition (II) may contain a nitrogen-based blowing agent such as melamine or isocyanurate in order to improve the expansion ratio. An agent may be blended.

In addition, the oxygen index (JIS K)
(Measured in accordance with 7201) is limited to 25 or more for the same reason as in the first invention.

The thickness of the substrate layer is preferably 0.1 to 5 mm for the same reason as in the first invention.

When the base material layer is heated, the phosphorus compound and the hydroxyl group-containing hydrocarbon are foamed and carbonized by a chemical reaction to form a fire-resistant heat-insulating layer and exhibit fire-resistant performance.

As the base material layer, for example, a sheet formed using a commercially available “Taikarito” (foamable fire-resistant paint) manufactured by Nippon Paint Co., Ltd. can be used.

As a method of laminating the above-mentioned base material and the sheet molding, the same method as in the first invention is used.

[0048]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

The performance of the molded sheet, the base material and the heat-expandable refractory sheet was evaluated by the following measurement methods, and the results are shown in Tables 1 to 3. (1) Oxygen index (index of fire resistance) The test piece was cut into a 60 mm width x 150 mm length to obtain a test piece.
The oxygen index was measured according to K 7201.

(2) Stress at break, elongation at break (indicator of handleability) Using "Tensilon" manufactured by Orientec, JIS
Crosshead speed 200mm according to K 7127
A tensile test was performed on a test piece having a width of 10 mm and an initial test length of 25 mm at a rate of / min, and the tensile stress and elongation at break were measured. (Stress at break: 1.2 × 10 ⁵ N / m ² or more, elongation 50
% Is preferable)

(3) Expansion Ratio (Indicator of Fire Insulation Resistance) 100 mm width × 100 mm length was cut into a test piece.
With the test piece placed horizontally, a cone calorimeter (“CONE2A” manufactured by Atlas) was used to measure 50
The thickness of the refractory heat-insulating layer formed after irradiating a heat amount of kW / m ² for 30 minutes was measured, and the expansion ratio with respect to the initial thickness was calculated. (Expansion ratio: preferably 20 times or more)

(4) 90-degree peel strength (indicator of adhesiveness) A test piece was cut into 25 mm width x 250 mm length using "Tensilon" manufactured by Orientec, according to JIS Z
90 at a peel rate of 300 mm / min according to 1528
The normal adhesive strength was measured by the peel-off peeling method. (90 ° peel strength: preferably 3 N / 25 mm or more)

The following two types of sheet moldings were used. -Sheet molded article (a) "Technofire 60152A" manufactured by Technical Fiber Products Inc. Non-combustible fiber material: glass fiber, fiber diameter: 2 to 8 m, fiber length: 10 to 20 mm, composition:
80% by weight of glass fiber and 20% by weight of thermally expandable graphite.

[0054] Sheet molding body (b) non-flammable fibers (material: rock wool fibers, fiber diameter: 2-7
μm, fiber length: 15 to 25 mm) and a mixture of 72% by weight of vermiculite (manufactured by Kisenmatech Co., Ltd.) and a phenol resin (“Regitop” manufactured by Gunei Chemical Co., Ltd.)
A resin binder consisting of 2.5% by weight and 0.5% by weight of a curing agent (manufactured by Wako Pure Chemical Industries, Ltd., phenolsulfonic acid) is spray-mixed, spread out in a sheet shape, and heated and pressed at 90 ° C. for 20 minutes to form a sheet molded body (B) was produced.

The thickness, stress at break and elongation at break (indicator of handleability) of the above molded sheet were measured.
It was shown to.

[0056]

[Table 1]

The following four types were used as substrate layers.・Base layer (a) Epoxy resin (Epicoat E manufactured by Yuka Shell Epoxy )
807 ”) and 100% by weight of a resin component composed of 40% by weight of a curing agent (“ Epicure FL052 ”manufactured by Yuka Shell Epoxy Co., Ltd.), 100 parts by weight of a heat-expandable inorganic substance (“ Vermiculite ”manufactured by Kinsei Matech Corporation), and ,
Inorganic filler ("Heidilite H-31" manufactured by Showa Denko KK)
100 parts by weight of aluminum hydroxide) were kneaded with a kneader kneader and formed into a sheet by a press molding machine.
This was cured at 30 ° C. for 30 minutes to produce a 0.5 mm thick base material layer (a).

Base layer (b) Butyl rubber (“# 052” manufactured by Exxon Chemical Co., Ltd.) 42
% By weight, polybutene (“# 100” manufactured by Idemitsu Petrochemical Co., Ltd.)
R ") 50% by weight, and a tackifier (hydrogenated petroleum resin,
100 parts by weight of a resin component consisting of 8% by weight of Tosnex Corporation "Escolets # 5320" and neutralized heat-expandable graphite (Tosoh Corporation "Frame Cut GRE"
P-EG ") 300 parts by weight were kneaded with a kneader kneader, and then formed into a sheet with a calendering machine to form a sheet having a thickness of 0.5 mm.
A thick base material layer (b) was produced.

Base material layer (c) 46% by weight of acrylate-styrene copolymer, 22% by weight of ammonium phosphate, pentaerythritol 6
An expandable fire-resistant paint ("Taikarit" manufactured by Nippon Paint Co., Ltd.) consisting of 26% by weight of a solvent (equivalent mixture of xylene / ethylbenzene) was used.

Base material layer (d) 0.1 mm thick polyethylene resin ("LE" manufactured by Mitsubishi Chemical Corporation )
520H ").

The thickness, oxygen index and 90 ° peel strength of the above substrate layer were measured and are shown in Table 2.

[0062]

[Table 2]

The following laminating method was used in order to obtain a laminate (a heat-expandable refractory sheet) of the above-mentioned sheet molded body and a base material layer. Lamination method (I) An acrylic pressure-sensitive adhesive (“SK Dyne” manufactured by Soken Chemical Co., Ltd.) was applied to the base material, and then adhered to a sheet molding to obtain a laminate. -Lamination method (II) A press molding machine heated to 90 ° C. was used to apply a pressure of 5 × 10 ⁶ N / m ² for 15 minutes, and the sheet compact and the substrate were melt-pressed to obtain a laminate. Lamination method (III) The epoxy resin for the base layer (a) and the curing agent before heat curing were applied to the sheet molded body, and then cured at 150 ° C. for 30 minutes to obtain a laminated body. Lamination method (IV) The step of spray-coating the coating material for the base material layer (c) on the sheet molded body and then drying is repeated, so that
A coating having a thickness of mm was formed to obtain a laminate.

(Examples 1 to 5, Comparative Examples 1 and 2) A thermally expandable refractory sheet was obtained by combining the sheet moldings and base materials shown in Table 3 and laminating them by the lamination method shown in Table 3. The oxygen index, stress at break, elongation at break, and expansion ratio were measured and are shown in Table 3.

[0065]

[Table 3]

All the examples satisfied the fire spread resistance, the handleability, and the fire insulating property, while the comparative example 1 had satisfactory handleability, and the comparative example 2 had the satisfactory fire spread property and the fire heat insulating property. Was not obtained. Further, in Examples 2 and 3, the heat-expandable refractory sheet has adhesiveness, so that the handleability is more excellent.

[0067]

The heat-expandable refractory sheet of the present invention has the above-described structure, and the heat-expandable inorganic substance contained in the sheet molded body expands by heating to form a fire-resistant heat-insulating layer. Is expressed. Furthermore, by laminating the base material on the sheet molded body, the sheet strength is imparted without impairing the fire insulation and fire spread resistance, so that the workability is improved and the base material itself is thermally expanded by heating. To form a fire-resistant heat-insulating layer, and the fire-resistance performance is further improved. Therefore, the heat-expandable refractory sheet of the present invention can be suitably used for a refractory joint material, a refractory cable, a refractory covering material and the like.

Continued on the front page F-term (reference) 2E001 DD01 DE01 GA03 GA24 GA47 GA85 HA31 HA32 HA33 HA34 HD01 HE01 JA06 JA13 JD02 LA16 4F100 AA01A AA01B AA37 AC10 AG00 AH02B AK01B AK04 AK09 AK12 AK25 AK28 AK33 AS01BA02 AE33 JA02A JA02B JJ07A JJ07B JK01 JL01 JL05 YY00A

Claims (2)

[Claims] 1. An average fiber diameter of 1 to 10 μm and an average fiber length of 5
On at least one side of a sheet formed body comprising 20 to 95% by weight of non-combustible fibers of 50 to 50 mm and 80 to 5% by weight of a thermally expandable inorganic substance, a base comprising a resin composition (I) containing a thermally expandable inorganic substance and a resin component is provided. A heat-expandable fire-resistant sheet comprising a laminate of material layers, wherein the base material layer made of the resin composition (I) has an oxygen index (measured in accordance with JIS K 7201) of 25 or more flame retardancy. A heat-expandable refractory sheet comprising: 2. An average fiber diameter of 1 to 10 μm and an average fiber length of 5
Resin composition (II) containing a phosphorus compound, a hydroxyl group-containing hydrocarbon and a resin component on at least one surface of a sheet molded body comprising 20 to 95% by weight of non-combustible fibers of 50 to 50 mm and 80 to 5% by weight of a thermally expandable inorganic substance. A heat-expandable refractory sheet formed by laminating a base material layer composed of the above resin composition (II), wherein the base material layer composed of the resin composition (II) has an oxygen index (JIS K 720).
A heat-expandable refractory sheet having a flame retardancy of 25 or more (measured in accordance with No. 1).