JPH0462536B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention provides a fiber sheet material that has excellent flame retardancy, dirt resistance and weather resistance, and is highly durable.
It relates to an efficient manufacturing method. [Prior Art] In recent years, sheet materials containing various synthetic resins have been used as building materials, interior materials, and members of vehicles, ships, aircraft, and the like. These synthetic resins have the disadvantage of generating a large amount of toxic or noxious gas or smoke when burned in a fire or the like. For example, a large amount of sheet materials containing polyvinyl chloride resin are used as the above-mentioned sheet materials, and various proposals have been made to make such sheet materials nonflammable or flame retardant. For example, Japanese Patent Publication No. 55-4582 proposes adding borates, zinc compounds, or iron compounds, aluminum hydroxide, or barium sulfate to the polyvinyl chloride resin to be applied to the sheet material base fabric. However, the results are still not completely satisfactory. Japanese Patent Publications No. 53-13505, Japanese Patent Publication No. 51-37297, and Japanese Patent Application Laid-Open No. 54-68470 propose the use of silicone resin as the nonflammable resin. In these cases, the effect of making it nonflammable or flame retardant is quite high, but when sheet materials coated with such silicone resins are used outdoors, for example as sheets for tents, they can deteriorate significantly during use. It gets dirty easily, and the surface of this silicone resin coating layer is soft and brittle.
There is a drawback that various solid dust powders may adhere to, enter and become buried, or the surface portion of this coating layer may peel off. In order to eliminate such drawbacks of the silicone resin coating layer, the present inventors first developed an antifouling/weather resistant material made of a thermoplastic synthetic resin with excellent stain resistance and weather resistance for the above-mentioned flame retardant coating layer. We proposed that a protective coating layer be provided. The formation of such an antifouling/weather-resistant coating layer has certainly solved the problem of various solid dust particles adhering to, penetrating, and being buried in the flame-retardant coating layer. However, it has been desired to further improve the adhesive strength between the flame-retardant coating layer and the antifouling/weather-resistant coating layer, as well as the durability of this adhesive. [Problems to be Solved by the Invention] When producing a flame-retardant fiber sheet material having a flame-retardant coating layer and an antifouling/weather-resistant coating layer, the present invention aims to solve the following problems: The object of the present invention is to provide a method for producing a flame-retardant fiber sheet material that can significantly increase the adhesive strength and durability of the material with a dirt/weather-resistant coating layer. [Means and effects for solving the problem] The method for producing a flame-retardant fiber sheet material according to the present invention includes a flame-retardant silicone resin and a silicone rubber on at least one side of a non-flammable base fabric made of a non-flammable fiber fabric. A flame retardant coating layer is formed by coating with a flame retardant coating material containing at least one selected from the following. When forming an antifouling/weather resistant coating layer made of a thermoplastic synthetic resin material, the surface of the flame retardant coating layer facing the antifouling/weather resistant coating layer is subjected to a corona discharge treatment. The method is characterized in that a graft layer is formed on the modified surface by graft polymerization of at least one monomer selected from ethyleneimine, acrylic acid, and acrylamide. The structure of the flame-retardant fiber sheet material obtained by the method of the present invention will be explained with reference to the accompanying drawings. In FIG. 1 of the accompanying drawings, the flame-retardant fiber sheet material has flame-retardant coating layers 2a and 2b formed on both sides of the non-flammable fiber base fabric 1, and corona discharge of each of the flame-retardant coating layers. Modified surface 6a by treatment,
6b and the graft layers 3a, 3 formed thereon.
b, adhesive layers 4a and 4b applied on each of the graft layers, and antifouling and weather-resistant coating layers 5a and 5b applied on each of these adhesive layers.
It consists of. An adhesive layer may not necessarily be necessary in the flame-retardant fibrous sheet material of the above embodiments. Also,
The stain-proof/weather-resistant coating layer and the graft layer thereunder may be formed only on one side of the base fabric. The noncombustible base fabric used in the method of the present invention is made of noncombustible fiber fabric, and such fabrics include glass fibers, asbestos fibers, metal fibers, and/or other inorganic noncombustible fibers. A knitted fabric or a non-woven fabric can be used. As a non-combustible base fabric, in order to improve adhesion with the flame-retardant coating layer, flexibility, water resistance, etc.
It is preferable that the cooling loss is 1.5% or less, the cross cover factor is 25 to 35, and the tensile strength in longitudinal and latitudinal directions is 50 Kg/25 mm or more, especially 200 Kg/25 mm or more, and 100 g/m ² or more, especially 200 to 900 g. A fabric having a basis weight of /m ² , particularly a glass fiber fabric, is preferred. In the method of the present invention, the flame-retardant silicone resin and silicone rubber used to form the flame-retardant coating layer include, for example, organopolysiloxane, polyacryloxyalkylalkoxysilane silicone resin, polyvinylsilane silicone resin, polysilthian , polysilazane, carbon polymers having silicon-containing side chains, polysilanes, and the like. For example, Shin-Etsu Chemical's flame-retardant silicone resin KR166, KR168, KR202,
KR2038, KR-101-10, etc. can be used in the method of the present invention. The flame-retardant silicone resin used in the method of the present invention may be modified into a flame-retardant silicone rubber using a curing agent (vulcanizing agent). The flame-retardant silicone resin used in the method of the present invention includes organopolysiloxane silicone resin,
It is preferable to use at least one selected from polyacryloxyalkylalkoxysilane silicone resins, polyvinylsilane silicone resins, and modified products of the silicone resins. The organopolysiloxane resin used in the method of the present invention has at least one organic substituent such as a vinyl group, an allyl group, a hydroxyl group, an alkoxy group having 1 to 4 carbon atoms, an amino group, a mercapto group, and It includes dimethylsiloxane-based silicone resins, polydiphenylsiloxane-based silicone resins, polymethylphenylsiloxane-based silicone resins, and resins made of copolymers thereof. The polyacryloxyalkylalkoxysilane silicone resin used in the method of the present invention has the general formula (R is a monovalent hydrocarbon group having 1 to 10 carbon atoms,
R' is hydrogen or a monovalent hydrocarbon group with 1 to 10 carbon atoms, R'' is a divalent hydrocarbon group with 2 to 10 carbon atoms, and n is an integer of 1 to 3. It includes a copolymer of oxyalkylalkoxysilane and at least one ethylenically unsaturated monomer. Furthermore, the polyvinylsilane silicone resin used in the method of the present invention has the following general formula: [However, R' is the same as above, B is OR' or OR''-
It also includes a copolymer of a vinyl silane compound represented by OR′ (R′, R″ are the same as above) and at least one ethylenically unsaturated monomer. The above ethylene monomer is a silicone resin. The monomers may be copolymerized at a content of 1 to 50% by weight. Examples of such monomers include styrene, methylstyrene, dimethylstyrene, ethylstyrene, chlorostyrene, bromostyrene, fluorostyrene, nitrostyrene, Or acrylic acid, methacrylic acid, methyl acrylate,
Ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate,
Butyl methacrylate, acrylamide, 2-
Hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, acrylonitrile, methacrylonitrile, 2-chloroacrylonitrile, vinyl acetate, vinyl chloroacetate, vinyl butyrate, vinyl chloride, vinyl bromide, vinyl fluoride, vinyldene chloride, vinyl halogen compound, and vinyl ethers. The silicone resins mentioned above may be combined with other resins such as epoxy resins, polyester resins, alkyd resins,
It may be modified with a polyamino resin or the like, or it may be modified with a fatty acid. In the flame-retardant fiber sheet material obtained by the method of the present invention, if self-extinguishing property is important, organopolysiloxane-based silicone resin should be
Polysiloxane component is 70% by weight in silicone resin
It is preferable to use the above, and in polyacrylooxyalkylalkoxysilane silicone resins and polyvinylsilane silicone resins, it is preferable that the ethylenically unsaturated monomer to be copolymerized is 50% by weight or less, particularly 20% by weight or less. . Further, when flexibility is important as well as self-extinguishing property, it is preferable to use an unmodified organopolysiloxane silicone resin.
These silicone resins may be solid at room temperature, flexible pastes, liquids, or dispersions such as emulsions, and are used with the addition of an appropriate solvent if necessary. In addition, silicone rubber is classified into room temperature curing type, heat curing type, ultraviolet ray curing type, and ultraviolet ray or electron beam curing type when looking at silicone rubber according to its curing mechanism. Metal carboxylates such as cobalt and iron, organic tin compounds such as diptyltin octoate and dibutyltin laurate, titanium chelate compounds such as tetrapropyl titanate and tetraoctyl titanate, N-N-dimethylaniline, triethanolamine, etc. By using a tertiary amine, a peroxide such as benzoyl peroxide, dicumyl peroxide, or t-butyl peroxide, and a platinum-based catalyst in combination, it is cured into a desired three-dimensional network structure. The flame-retardant coating layer may be formed only from the above-mentioned flame-retardant silicone resin and/or silicone rubber, but these materials contain 30 to 300%, preferably 100 to 250% of their weight % of other fillers such as silica-based fillers, potassium titanate-based fillers, asbestos fibers, mica, and other inorganic heat-resistant materials may be mixed. The filler serves to reinforce the resin layer formed by the silicone resin varnish, and various inorganic substances such as titanium oxide, mica, alumina, talc, glass fiber powder, rock wool fine fibers, silica powder, and clay may be used. However, when it is desired to impart surface smoothness to the obtained flame-retardant fiber sheet material, a filler in the form of fine powder of 50 μm or less is generally added so as not to impair the surface smoothness of the sheet. It is preferable to use Furthermore, among inorganic fillers, it is particularly effective to use alkali titanate to improve the heat resistance of the product. That is, the alkali titanate is used by being blended into the silicone resin varnish, and is used to ensure that the sheet of the present invention maintains sufficient disaster prevention properties. The alkali titanate will be explained in more detail. Alkali titanate has the general formula M ₂ O.
Represented by nTiO ₂・mH ₂ O (in the formula, M represents an alkali metal such as Li, Na, K, etc., n represents a positive real number of 8 or less, and m represents a positive real number of 0 or 1 or less). More specifically, it is an alkali titanate with a salt-type structure represented by Li ₄ TiO ₄・Li ₂ TiO ₃ (0<n<1, m=0), and Na ₂ Ti ₇ O ₁₆・K ₂ Ti ₆ O ₁₅・K ₂ Ti ₈ O ₁₇ (n<8,
m=0), and an alkali titanate having a tunnel structure. Among these, the general formula K ₂ O・
Potassium hexatitanate and its hydrate represented by 6TiO ₂ mH ₂ O (in the formula, m is the same as above) are suitable in that they greatly improve the fire resistance and heat insulation properties of the final object. Not only potassium hexatitanate but also alkali titanates are generally powders or fibrous microcrystals, but among these, those with a fiber density of 5 μm or more and an aspect ratio of 20 or more, particularly 100 or more, can be obtained by the method of the present invention. This results in favorable results in improving the strength of flame-retardant fiber sheet materials. In addition, fibrous potassium titanate in particular has a high specific heat and excellent heat insulation performance, so in the method of the present invention, it is possible to impart excellent fire and heat resistance to the flame-retardant fiber sheet material obtained. The alkali titanate can be used as it is, but in order to achieve better reinforcing hardening, it is necessary to add a silane coupling agent, e.g., about 0.05 to 1.0% by weight based on potassium titanate. It is preferable to use fibers whose surfaces have been treated with a silane coupling agent such as γ-aminopropyltriethoxysilane or γ-glycidoxypropyrotrimethoxysilane. Furthermore, in the method of the invention, the flame-retardant coating layer may contain a high refractive index inorganic compound or a heat-absorbing inorganic compound. High refractive index inorganic compounds have excellent shielding performance against radiant heat, and endothermic inorganic compounds, when in direct contact with slag during welding or fusing,
Heat is generated at this contact surface, and an endothermic reaction occurs during its decomposition, lowering the temperature of the slag. Therefore, the above-mentioned inorganic compound can suppress the collapse and penetration failure of the flame-retardant coating layer of the present invention, and further protect the sheet base material. The high refractive index inorganic compound useful in the method of the present invention may have a refractive index of 1.5 or more, but those with a specific gravity of 2.8 or more are particularly suitable, and examples thereof include the following. 1 Dolomite (dolomite, specific gravity 2.8~2.9, refractive index 1.50~
1.68) Magnesite (Rhiochite 〃3.0～3.1 Refractive index 1.51～
1.72) Aragonite (specific gravity 2.9~3.0 〃 1.63~
1.68) Apatite (Next lime 〃3.1〜3.2 〃1.63〜
1.64) Spinel (Spinel 〃3.5〜3.6 〃1.72〜
0.73) Corundum (〃3.9〜4.0 〃1.76〜
1.77) Powder of crushed natural or synthetic minerals such as zircon (〃3.90~4.10〃 1.79~1.81) carbon silicon (〃3.17~3.19〃 1.65~2.68) 2 Fritz or high refractive glass or combination of phosphorite and snakestone fine powders or granules of dissolved phosphorous fertilizers and other similar solid solutions obtained as solid solutions;
Fibrous materials or foams, etc. In addition, endothermic inorganic compounds include calcined gypsum, alum, calcium carbonate, aluminum hydroxide, hydrosalcite aluminum silicate, etc., crystal water releasing type, carbon dioxide gas releasing type, decomposition endothermic type, phase change type, etc. Examples include type inorganic compounds. A coating mixture useful in the method of the invention is obtained by mixing and dispersing the fibrous alkali titanate and optionally a high refractive index inorganic compound and/or an endothermic inorganic compound in a silicone resin. All known methods can be used to mix and disperse such a mixture. In addition, the above coating mixture contains dispersants and defoamers to uniformly disperse each component, colorants to adjust color and mechanical strength, resin powder, flame retardants, metal powder, etc. Various fillers may be mixed as appropriate. In addition, copper powder, nickel powder,
Mixing metal powder such as brass powder or aluminum powder is preferable from the viewpoint of improving the surface heat reflection effect and the penetration suppressing effect. To form and bind a flame-retardant coating layer on a non-flammable base fabric, for example, a flame-retardant silicone resin, an alkali titanate, and if necessary, a high refractive index inorganic compound and/or an endothermic inorganic compound are included. After adding appropriate curing accelerators and additives to the mixture, an organic solvent such as toluene, xylene, trichlene, etc. is further added as necessary to prepare a dispersion liquid of an appropriate concentration, and this dispersion liquid can be applied by dipping, spraying, etc. It is coated on one or both sides of the nonflammable base fabric by a conventionally well-known coating method such as a roll coating method, a reverse roll coating method, or a knife coating method, and is applied at room temperature or under heating, preferably.
The silicone resin is cured by heat treatment within the range of 150 to 200°C for 1 to 30 minutes, and is integrally fixed to the above-mentioned base material. The blending ratio of silicone resin and alkali titanate, high refractive index inorganic compound, and/or endothermic inorganic compound, etc. varies depending on the type and particle size of the silicone resin and inorganic compound used, but in general, too little silicone resin will cause problems. As a result of insufficient strength of the flame-retardant coating layer, when this is used as a flame-retardant fiber sheet material, cracks may occur in the flame-retardant coating layer or the flame-retardant coating layer may peel off from the base fabric. On the other hand, if there is too much silicone resin, heat resistance decreases, and in severe cases, flaming combustion may occur. Therefore, in the method of the present invention, the amount of alkali titanate added to 100 parts by weight (hereinafter referred to as parts by weight) of the silicone resin is 1 to 200 parts, preferably 1 to 200 parts.
30 to 100 parts, and if a high refractive index inorganic compound and/or an endothermic inorganic compound are added to these, up to 400 parts, and an alkali titanate equivalent to 1/4 of the same weight. Although it can be blended in place of , it is usually preferably in the range of 10 to 300 parts.
Note that part or all of these high refractive index inorganic compounds and endothermic inorganic compounds can be replaced with commonly used inorganic pigments, inorganic extender fillers, inorganic powders that impart flame retardancy, etc. The amount used is preferably 400 parts or less, more preferably 300 parts or less per 100 parts of silicone resin. In order to improve the curing of the present invention, a flame retardant may be used in combination in the flame retardant coating layer. The flame retardants used here are not particularly limited, but include, for example, organic flame retardants such as phosphate ester type, organic halogen compound type, and phosphazene compound type, calcined gypsum, alum, potassium carbonate, and hydroxide. There are endothermic decomposition type inorganic compounds made of inorganic compounds such as crystal water release type, carbon dioxide gas release type, decomposition endothermic type and phase change type such as aluminum and hydrotalcite aluminum silicate, and inorganic flame retardants such as antimony compounds. . There are no particular limitations on the weight or thickness of the flame-retardant coating layer, but it is generally 10 to 1000 g/m ² on one side, preferably 50 g/m 2 on one side.
It is preferably formed with a weight of ~700 g/m ² and a thickness of 10-500 μm on one side. In the method of the invention, the surface of the flame-retardant coating layer facing the antifouling/weather-resistant coating layer is treated with corona discharge, and a graft layer is formed on this modified surface. In this corona discharge treatment, a high voltage is applied between a roller that supports the sheet material to be treated and an electrode placed opposite to it to generate a corona discharge. It is something that will be processed. In the method of the present invention, the corona discharge treatment can be carried out continuously while the sheet material to be treated is moved at a predetermined speed between a pair of rolled discharge electrodes as shown in FIG. 2, for example. In FIG. 2, a pair of rolled discharge electrodes 11 and 1
2 each has one metal electrode core 13, 14 and a non-electrically conductive resin layer 15, 16 (for example, a rubber layer) covering it. The electrode core 13 of one roll-shaped discharge electrode is connected to the voltage power supply 17, and the electrode core 14 of the other roll-shaped electrode is connected to the ground 1.
8 is connected. The sheet material 20 fed through the guide roll 19 has its back side 21
The discharge electrodes are moved at a constant speed (for example, 2
~10m/min). At this time, when a predetermined voltage (100 to 200 V) is applied between both rolled electrodes 11 and 12, a corona discharge of 10 to 60 A is generated, and the surface 22 of the flame retardant coating layer of the sheet material 20 is treated by this corona discharge. receive. The distance A between the circumferential surfaces of both electrodes is 30 mm or less, generally 5 ~
It is 20mm. The corona discharge treated sheet material 20 is passed through a guide roll 23 and wound up to form a roll 24 . For corona discharge treatment, spark gap method,
Vacuum tube method, solid state method, etc. can be used. In order to improve the adhesion of the treated surface of the sheet material, its critical surface tension should be increased from 35 to
It is preferable to use 60 dyn/cm, and for this purpose, the surface of the sheet material to be treated should be
50000W/m ² /min, preferably 150-40000Wm ² /
It is preferable to apply processing energy of about 1 minute. The amount of energy to be applied (voltage, current amount, distance between electrodes, etc.) depends on the width of the sheet material to be processed,
It is determined by considering processing speed, etc. For example, when corona discharge treatment is applied to the surface of a sheet material with a width of 2 m at a processing speed of 10 m/min, the output (power consumption) is preferably about 4 kW to 800 kW, but the conditions are not necessarily limited to this. isn't it. The corona discharge device used in the method of the invention may be of the usual metal electrode type. For example, vapor of at least one polymer selected from ethyleneimine, acrylic acid, and acrylamide is applied to the modified surface of the flame-retardant coating layer modified by corona discharge treatment as described above.
Graft polymerization is performed by contacting at a temperature of 100°C to 100°C or using a solution to form a highly adhesive graft layer. This graft layer is firmly bonded to the surface of the flame retardant coating layer and significantly improves its adhesion. Generally, there are no particular limitations on the thickness or weight of the graft layer, but it is preferable that the graft layer has a thickness of 0.05 to 5 μm. An antifouling and weatherproof coating layer is then bonded onto the graft layer, with or without adhesive. Examples of useful adhesives include melamine adhesives, phenolic adhesives, epoxy adhesives, polyester adhesives, polyethyleneimine adhesives, polyisocyanate adhesives, polyurethane adhesives, and acrylic adhesives. Examples include, but are not limited to, adhesives, polyamide adhesives, and copolymer adhesives such as vinegar-PVC adhesives and vinyl acetate-ethylene adhesives, and known adhesives. can be selected and used as appropriate. As the antifouling/weather resistant thermoplastic synthetic resin used in the method of the present invention, fluorine-containing polymer resins and polyacrylic resins can be used. In other words, the antifouling/weather-resistant coating layer is generally formed by subjecting the flame-retardant coating layer to corona discharge treatment and graft polymerization treatment, and then applying a paint made of fluorine-containing polymer resin or polyacrylic resin thereon. or by adhering the above resin film. The resin constituting the fluorine-containing polymer resin layer includes various polyfluoroethylenes synthesized from monomers in which one or more hydrogen atoms of ethylene are replaced with fluorine atoms, such as polytetrafluoroethylene,
There are also various polyfluorochloroethylenes that partially contain chlorine, such as polytrifluorochloroethylene, but also polyvinyl fluoride, polyvinylidene fluoride, polydichlorodifluoroethylene,
Others are also included. These fluorine-containing polymer resins all have high melting points and cannot be subjected to normal calender processing, so they must be melted and then extruded, or powdered resins must be heated under pressure and molded into a film. is common. However, the method is not particularly limited to this method. The thickness of the film is generally 0.001mm to 0.5mm, preferably 5 to 5mm.
The thickness is approximately 50 μm, but there is no particular limitation, as long as the objective of weather resistance, antifouling property, and durability is achieved, the thickness can be made thicker or thinner than the above thickness. Further, the fluorine-containing polymer resin film may be mixed with other resins such as MMA or the like, as long as the object of the present invention is achieved. Commercially available fluorine-containing polymer resin films used in the present invention include Tedlar film (DuPont trademark) and Afrex film (Asahi Glass trademark). In the method of the present invention, the stain-proof and weather-resistant coating layer is
It may also be formed from polyacrylic resin. For this reason, polyacrylic resin films are generally used. This kind of polyacrylic resin film is
It may be based on the T-die method, the inflation method, or any other method. Further, it may be stretched or unstretched, but the elongation is preferably about 100 to 300%. In addition, as mentioned above, the thickness is usually 5 μm ~
The thickness is approximately 50 μm, but it may be made somewhat thicker or thinner if sufficient weather resistance and antifouling properties are achieved. The film material is a polyalkyl methacrylate film, for example, one whose main material is methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, etc., or acrylate, vinyl acetate, vinyl chloride, styrene, etc.
A homopolymer or copolymer containing acrylonitrile, methacrylonitrile, etc. as a homomonomer or comonomer component and molded into a film is preferable. The antifouling/weather-resistant coating layer is made of a fluorine-containing polymer resin film or a polyacrylic resin film having a substantially smooth surface as described above, and if necessary, the adhesive surface thereof is subjected to corona discharge treatment or low temperature treatment. It is preferable to improve the adhesion by performing plasma treatment or the like and then bonding this onto the graft layer using an adhesive. However, as another method for forming an antifouling/weather-resistant coating layer, there is a method in which a solution or emulsion of the above-mentioned resin is applied to the surface of the graft layer or the surface of the adhesive layer applied thereon and dried and solidified. The film used for forming the antifouling/weather-resistant coating layer preferably has a tensile strength of 100 Kg/cm ² or more. In addition, the antifouling/weatherproof coating layer is 1~
Weight of 50g/m ² , preferably 3-30Kg/m ² , or
The thickness is preferably 5 μm or more (usually 10 to 50 μm), more preferably 30 to 15 μm. In the method of the present invention, the stain-proof and weather-resistant coating layer is
In addition to the above-mentioned fluorine-containing polymer resin and polyacrylic resin, a laminate of a polyvinylidene fluoride resin layer and a polyacrylic resin layer, or a polyvinylidene fluoride resin layer, a polyacrylic resin layer, and a polychloride It may also be a laminate with a vinyl resin layer. In these laminates, it is preferable that the polyvinylidene fluoride resin layer has a thickness of 2 to 3 μm, the polyacrylic resin layer has a thickness of 2 to 4 μm, and the polyvinyl chloride resin layer has a thickness of 40 to 45 μm. However, it is not limited to these numbers. [Example] The present invention will be explained in more detail with reference to the following example. Example 1 and Comparative Example 1 Viscosity was applied to both sides of a plain weave glass cloth with a thickness of 0.25 mm.
100 parts of dimethylpolysiloxane endblocked with vinyl groups at both ends of 10000CS, 1.0 part of methylhydrodiene polysiloxane with viscosity of 40CS, platinum compound catalyst, 0.11 part of benzotriazole as an addition reaction retarder, 1.0 part of carbon black, hydroxide. A light gray paste-like addition reaction curable silicone rubber composition containing 50 parts of aluminum powder as a flame retardant improver was coated using a knife coater method, and heated at 170°C for 5 minutes to form a thick coating on both sides. A flame-retardant intermediate sheet (Sample 1) having a flame-retardant silicone rubber layer formed thereon with a thickness of 0.1 mm was obtained. The flame retardance of this flame retardant silicone rubber itself was 0.16 mm thick and passed UL94V-0. Both sides of the flame-retardant intermediate sheet (sample 1) were subjected to corona discharge treatment using the apparatus shown in FIG. The intermediate sheet (sample 1) was fed between a pair of discharge electrodes at a speed of 10 m/min such that one layer of the intermediate sheet was in contact with the circumferential surface of a rolled electrode connected to ground. On the back side of this intermediate sheet,
The distance A between both electrodes was 10 mm, and corona discharge treatment was performed continuously at a voltage of 160 V, a current of 18 A, and a maximum output of 8 kW (power consumption: 7.9 kW/hr). At this time, the diameter of the metal electrode core of both electrodes was 20 cm, the thickness of the resin layer was 2 mm (roll diameter 20.4 cm), the roll length was 2 m, and the discharge width was 1.92 m. At this time, the energy radiated to the sample surface was approximately 440 W/m ² /min. A similar corona discharge treatment was applied to the opposite side of the intermediate sheet. Acrylic acid vapor generated at room temperature is introduced into the apparatus to the obtained corona discharge treated intermediate sheet,
The surface of the intermediate sheet was brought into contact with acrylic acid vapor at a temperature of 60° C. for 5 minutes to form a graft-polymerized polyacrylic acid graft layer (thickness: 1.5 μm). Obtained graft intermediate sheet (sample 2)
I got it. In Example 1, a polyacrylic resin adhesive (manufactured by Sony Chemical Co., Ltd., SC-462) was applied to the surface of the graft layer of Sample 2 in an amount of 20 g/m ² using a 100-mesh gravure roll, and the adhesive was applied at room temperature. Dry. Next, a vinylidene fluoride resin film (thickness: 3 μm) was heat-pressed onto the surface of the adhesive layer. In Comparative Example 1, the same antifouling/weather-resistant coating layer forming operation as in Example 1 was performed without subjecting the surface of the flame-retardant coating layer of Sample 1 to corona discharge treatment and graft polymerization treatment. Table 1 shows the peel strength between the flame-retardant coating layer and the antifouling/heat-resistant coating layer of each sheet-like product obtained. Example 2 and Comparative Example 2 In Example 2, the same operations as in Example 1 were performed, and in Comparative Example 2, the same operations as in Comparative Example 1 were performed. However, a 3 μm thick polyacrylic resin film was used to form an antifouling and weatherproof coating layer. The results are shown in Table 1. Example 3 and Comparative Example 3 In Example 3, the same operations as in Example 1 were performed, and in Comparative Example 3, the same operations as in Comparative Example 1 were performed. However, in order to form an antifouling and weather-resistant coating layer, FKC film (manufactured by Kureha Chemical Co., Ltd.) consists of a vinylidene fluoride resin layer (2 μm thick), a polyacrylic resin layer (2 to 4 μm), and a polyvinyl chloride resin layer.
A three-layer structure in which 45 μm thick layers were laminated was used. The results are shown in Table 1.

[Table] *: In peel strength measurement, the adhesive film was broken without peeling.
Examples 4 and 5 and Comparative Example 4 In Example 4, dimethylsiloxane/methylvinylsiloxane copolymer (mole ratio of both units
0.14:99.86) 100 parts of raw rubber and BET surface area 170m ² /
chloroplatinic acid was added to a silicone rubber composition consisting of 40 parts of hydrophobized fumed silica at 30 ppm by weight of platinum.
40 parts of aluminum hydroxide powder, 10 parts of mica powder, and 1.5 parts of dicumyl peroxide were added and mixed, and this mixture was coated on both sides of a glass cloth with a thickness of 0.6 mm by the calendering method, and heated at 200°C for 5 minutes. Sulfurized. (The flame retardancy of this silicone rubber itself was 0.16 mm thick and passed UL94V-0). The thickness of each silicone rubber layer was 0.6 mm. The obtained flame-retardant intermediate sheet material is designated as Sample 3. The flame-retardant coating layer of Sample 3 was subjected to corona discharge treatment in the same manner as described in Example 1. The same graft polymerization treatment as described in Example 1 was performed on the surface of the flame retardant coating layer of this corona discharge treated intermediate sheet. However, acrylamide vapor was used instead of acrylic acid vapor, and the contact time was 3 minutes. The thickness of the formed graft layer was 1.8 μm. The obtained intermediate sheet-like material is designated as Sample 4. In Example 4, a polyurethane adhesive having the following composition was applied to the surface of the graft layer of Sample 4: Nitsuporan.
3022 (manufactured by Nippon Urethane Co., Ltd., solid content 35%) 100 parts by weight and Coronate L (manufactured by Nippon Urethane Co., Ltd.) 15 parts by weight were coated with 60 mesh gravure coat to give 25 g/
It was applied in an amount of m ² and dried. The same KFC film as described in Example 3 was heat-pressed onto the surface of this adhesive layer. In Example 5, the same operations as in Example 4 were performed. However, ethyleneimine was used instead of acrylamide when forming the graft layer. The thickness of the graft layer was 2.0 μm. In Comparative Example 4, a KFC film was directly attached to the surface of the flame retardant coating layer of Sample 3 in the same manner as in Example 4. The peel strength and durability (change over time) of each sheet-like product obtained were measured. The results are shown in Table 2.

〔Effect of the invention〕

In the method for producing a flame-retardant fiber sheet material according to the present invention, the flame-retardant coating layer and the antifouling/weather-resistant coating layer can be firmly bonded, and therefore, the durability thereof is also excellent. Furthermore, the flame-retardant fiber sheet material obtained by the method of the present invention has less staining and excellent weather resistance. Furthermore, the flame-retardant fiber sheet material obtained by the method of the present invention is particularly unlikely to emit smoke or generate heat even at high temperatures. The method of the present invention can be applied to construction materials and interior materials of gymnasiums, warehouses, markets, playgrounds, factories, parking lots, various accommodation facilities, etc. where fire is expected, as well as tents, awnings, blinds, sheets, partitions, etc. Flame-retardant fiber sheet materials used in a wide variety of applications can be efficiently produced, and are therefore practically useful.

[Brief explanation of the drawing]

FIG. 1 is an explanatory cross-sectional view showing the structure of one embodiment of a flame-retardant fiber sheet material obtained by the method of the present invention, and FIG. 2 is an illustration of an example of a corona discharge treatment apparatus used in the method of the present invention. It is an explanatory diagram. 1... Nonflammable fiber base fabric, 2a, 2b... Flame retardant coating layer, 3a, 3b... Graft layer, 4a, 4b
...adhesive layer, 5a, 5b...antifouling/weather resistant coating layer, 6a, 6b...corona discharge modified surface, 11,
12...discharge electrode, 13,14...electrode core, 1
5, 16... Resin layer, 19, 23... Guide roll, 20... Sheet material to be treated, 22... Surface to be treated of sheet material.

Claims (1)

[Scope of Claims] 1. At least one side of a noncombustible base fabric made of noncombustible fiber fabric is coated with a flame retardant coating material containing at least one selected from flame retardant silicone resin and silicone rubber. forming a flame-retardant coating layer, and forming an anti-fouling/weather-resistant coating layer made of a thermoplastic synthetic resin material with excellent anti-fouling/weather resistance on at least one of the flame-retardant coating layers, The surface of the flame retardant coating layer facing the antifouling/weather resistant coating layer is subjected to corona discharge treatment to modify it, and on this modified surface, ethyleneimine,
A method for producing a flame-retardant fiber sheet material, which comprises forming a graft layer by graft polymerizing at least one monomer selected from acrylic acid and acrylamide. 2. The method according to claim 1, wherein the graft layer and the antifouling/weather-resistant coating layer are bonded together using an adhesive. 3. The nonflammable base fabric is made of glass fiber fabric.
A method according to claim 1. 4. The method according to claim 1, wherein the flame-retardant coating material consists of at least one selected from the flame-retardant silicone resin and silicone rubber. 5. The flame-retardant coating material consists of a mixture of at least one selected from the flame-retardant silicone resin and silicone rubber and a non-flammable or flame-retardant filler in an amount of 30 to 300% based on the weight thereof. A method according to claim 1. 6. The method according to claim 1, wherein the graft layer is formed to have a thickness of 0.05 to 5 μm. 7. The method according to claim 1, wherein the antifouling/weather-resistant synthetic resin comprises at least one selected from fluorine-containing polymer resins and polyacrylic resins. 8. The method according to claim 1, wherein the antifouling/weather-resistant coating layer is formed of a laminate consisting of a polyvinylidene fluoride resin layer and a polyacrylic resin layer. 9. The method according to claim 1, wherein the antifouling/weather-resistant coating layer is formed of a laminate of a polyvinylidene fluoride resin layer, a polyacrylic resin layer, and a polyvinyl chloride resin layer.