JP5620150B2 - Combustion resistant sheet - Google Patents

Description

The present invention relates to a flame resistant sheet.

Conventionally, thermoplastic resin has been used as a plant plate, pipe, pipe joint, sheet as a material having excellent physical properties such as impact resistance and heat resistance and chemical properties such as solvent resistance and acid resistance. It is used for many applications such as film.
However, when it burns, toxic gas and a large amount of black smoke are generated, and in the use of vehicles such as trains, the safety of passengers is impaired in the event of a fire.

As a method for improving the flame retardancy of a thermoplastic resin, for example, a method of adding a flame retardant such as aluminum hydroxide or magnesium hydroxide to a vinyl chloride resin has been proposed (see, for example, Patent Document 1).
Further, a method of adding graphite to a vinyl chloride resin has been proposed (see, for example, Patent Document 2).

Japanese Patent Laid-Open No. 5-25347 JP 09-227747 A

  However, with such a thermoplastic resin composition, Section 83, “Fire Control for Vehicles,” in Section 5 of the “Ministerial Ordinance for Establishing Technical Standards Regarding Railways (Ministry of Land, Infrastructure, Transport and Tourism Ordinance No. 151, December 25, 2001)” In a combustion test conducted by a method compliant with the above, a large amount of filling is required in order to develop a combustion suppression effect, and therefore, physical properties such as impact resistance and secondary workability such as vacuum formability are significantly reduced. There was a drawback of inviting.

  This invention is made | formed in view of the said problem, and it aims at providing the flame-resistant sheet | seat excellent in the flame retardance, impact resistance, and secondary workability.

The combustion-resistant sheet of the present invention is
A combustion resistant sheet comprising a combustion resistant layer composed of a flame resistant resin composition and a coating layer,
The flame-resistant layer is formed of a flame-resistant resin composition containing a thermoplastic resin and graphite, and is defined by [the thickness of the flame-resistant layer] × [the thermal conductivity of the flame-resistant layer]. Thermal conductivity of the conductive layer] is 1.2 mW / K or more,
The coating layer is formed of a thermoplastic resin composition.
In such a flame resistant sheet,
It is preferable that the flame resistant layer is formed of a flame resistant resin composition further including an acrylic processing aid.
The coating layer is preferably formed of a thermoplastic resin composition containing a vinyl chloride resin containing an impact modifier and a processing aid.
The coating layer is preferably formed of a thermoplastic resin composition containing a styrene resin.

  ADVANTAGE OF THE INVENTION According to this invention, the flame-resistant sheet excellent in the flame retardance, impact resistance, and secondary workability can be provided.

The combustion resistant sheet of the present invention is formed by laminating a combustion resistant layer and a coating layer. The flame resistant layer may have a multilayer structure with different thermal conductivities.
In this invention, when using a combustion-resistant sheet | seat as interior materials, such as a railway vehicle, the surface exposed to a passenger side is called the surface. Moreover, in order to efficiently express the combustion resistance effect, it is preferable to dispose the coating layer on the back surface side of the combustion resistance layer. However, depending on the purpose, it may be a three-layer structure in which coating layers are laminated on both the front and back surfaces of the flame-resistant layer, or a laminated structure of four or more layers such as these layers being alternately laminated. It may be.
Printing processing may be given to the surface layer surface of a combustion-resistant layer and / or a coating layer, and a decoration layer may be provided. Thereby, the outstanding processing characteristic which a thermoplastic resin has can be exhibited. In addition to these layers, various functional layers such as a protective layer and an antireflection layer may be formed.

  The flame resistant layer only needs to be formed of a flame resistant resin composition, and includes at least a layer containing a thermoplastic resin and graphite. Not only a combination of a thermoplastic resin and graphite, which will be described later, It may be a multilayer structure composed of a combination of a layer composed of a thermoplastic resin and a different type of filler such as fine particles such as copper and aluminum or fine fibers and a layer containing graphite. Thus, by combining specific materials, the excellent characteristics of the materials themselves can be sufficiently exhibited. For example, flame retardance can be improved as an interior material for railway vehicles and the like.

Here, the graphite is not particularly limited, and various conventionally known ones can be used, and either natural graphite or artificially produced graphite may be used. For example, scaly graphite, scaly graphite, scaly (lumpy) graphite, earthy graphite, artificial graphite, expanded graphite, expanded graphite, pyrolytic graphite and the like can be mentioned. These graphites may be refined, dried, fired, pulverized and / or classified. The pulverization process is not particularly limited, and can be performed using a conventionally known apparatus such as a rod mill, a ball mill, or a jet mill.
Thus, by adding graphite to the thermoplastic resin, the flame resistance can be remarkably improved in the flame resistant sheet. Therefore, a combustion test conducted by a method in accordance with Article 83 of Section 5 of the Fire Countermeasures for Vehicles in the "Ministerial Ordinance for Establishing Technical Standards on Railways (December 25, 2001, Ministry of Land, Infrastructure, Transport and Tourism Ordinance No. 151)" In this case, the effect of suppressing the ignition of the specimen can be expressed.

The carbon source used as the raw material of the graphite is not particularly limited, and may be any of naturally occurring materials, artificially produced materials such as natural graphite and quiche graphite.
The shape of the carbon source used as the raw material for graphite and the coke described later may be either solid or powder.

  Scaly graphite is a kind of naturally produced graphite and is conventionally known, and is not particularly limited, and any graphite can be used. Scalar graphite is preferable because it has a large aspect ratio of particles, allows heat to escape more in the plane direction than in the thickness direction, and improves the flame retardancy of the interior material. In addition, the scaly graphite includes scaly graphite and exfoliated graphite having a larger aspect ratio. Generally, the aspect ratio of flake graphite is about 30, and the aspect ratio of exfoliated graphite is about 100.

  Artificial graphite is artificially produced by heating a carbon source as a raw material at a high temperature, and any graphite can be used as long as it is conventionally known. For example, graphite obtained by heat-treating coke includes that produced by pulverizing an artificial graphite electrode produced by heat-treating a binder such as coke and coal tar at a high temperature of 2000 ° C. or higher. What does not contain binders, such as coal tar, is preferred because of its high thermal conductivity.

  The expanded graphite is a conventionally known one, and is not particularly limited, and any one can be used. Usually, it is produced by chemically treating graphite. For example, natural scale-like graphite, pyrolytic graphite, quiche graphite and other powders such as concentrated sulfuric acid, nitric acid, selenic acid and other inorganic acids and concentrated nitric acid, perchloric acid, perchlorate, permanganate, dichromate, Examples include crystalline compounds that maintain a carbon layer structure obtained by inserting an inorganic acid between graphite layers using a strong oxidizing agent such as hydrogen peroxide and performing acid treatment.

The expanded graphite is obtained by expanding the expanded graphite, and the method for expanding is not particularly limited. For example, a method of performing a heat treatment for several minutes to several hours at a temperature of several hundred to 1,000 degrees in a furnace and the like can be mentioned.
Expanded graphite expands expanded graphite and then increases the surface area of the graphite by opening the interlayer of the graphite that has been pulverized, thus increasing the probability that the graphites are closer together after molding the flame resistant sheet. Conceivable.

Pyrolytic graphite is artificially produced by heating a carbon source as a raw material at a high temperature, and any graphite can be used as long as it is conventionally known. . Pyrolytic graphite is produced by, for example, heat-treating a coke raw material at a high temperature of 2000 to 3000 ° C. or higher, or by heating the graphite at a high temperature (about 2000 to 3000) in a hydrocarbon atmosphere. And those produced by carbon deposition on the graphite surface. The graphite is not particularly limited, and may be any naturally occurring one, artificially produced one, such as natural graphite or quiche graphite. The shape of graphite and coke may be solid, powder, or the like.
Pyrolytic graphite is particularly preferable because it has a thin shape and a high graphitization degree by high-temperature treatment, so that the combustion resistance is increased.
Note that pyrolytic graphite includes graphite obtained by heat treating coke, including coke powder that is heat treated at a high temperature of 2000 ° C. or higher when producing SiC, and has a tendency to increase the thermal conductivity with less impurities. Therefore, it is particularly preferable.

  The size and shape of graphite to be used are not particularly limited, but considering the dispersibility and / or physical properties of the thermoplastic resin, the average particle size is preferably about 500 μm or less, more preferably about 300 μm or less. . Considering the thermal conductivity described later, the larger one is preferable because the probability of contact between graphites increases (the probability of contact with a material such as a thermoplastic resin having low thermal conductivity decreases) and the thermal conductivity increases. In order to ensure a certain degree of thermal conductivity, it is preferably about 15 μm or more. In order to maintain good dispersibility, moldability and the like in the molded body, about 25 μm to 200 μm is more preferable, and about 30 to 100 μm is particularly preferable. If the average particle size is too small, the bulk specific gravity increases, which may cause inconvenience in handling. Here, the particle size is, for example, a value measured by using a laser diffraction particle size distribution analyzer SALD-2200 (manufactured by Shimadzu Corporation) after sufficiently dispersing graphite in a THF solution.

  In addition, when the flame-resistant sheet of the present invention is used as an interior material for a railway vehicle, the shape of graphite is a thin plate rather than a spherical shape from the viewpoint of delaying ignition by quickly releasing heat from a flame during a fire. The shape is preferable, and this makes it easier to release heat in the surface direction than in the thickness direction, and the flame retardancy of the interior material can be improved. For this reason, those having a large aspect ratio are preferred. In particular, when a combustion-resistant sheet is used as an interior material for a railway vehicle, it is preferable to orient the graphite having a long diameter along the surface direction of the interior material. This makes it possible to efficiently release heat from the flame.

The degree of graphitization of graphite is an index of crystallinity that is directly measured by the half-value width of X-ray diffraction, which will be described later. In graphite, if the value is high (if the half-value width is small), the thermal conductivity becomes high and difficult. From the viewpoint of improving flammability, a higher one is more preferable. For the same purpose, graphite having less impurities is more preferable.
The relative degree of graphitization can be measured, for example, by the following method.
The full width at half maximum (FWHM) of the largest peak appearing in the vicinity of 52 ° to 57 ° by 2θ is measured by X-ray diffraction. The smaller this value, the higher the graphitization degree.
For example, when this half-value width is measured using an X-ray diffractometer manufactured by Brugger AXS, the half-value width is 0.47 for earth-like graphite and 0.53 for artificial graphite, and graphitization has not progressed. Graphite, scaly graphite, and pyrolytic graphite are preferable because they are as small as about 0.23 and have a high degree of graphitization, thus increasing the thermal conductivity. Among them, pyrolytic graphite is particularly preferable because it is not only highly graphitized but also thinner and has less impurities.
The graphitization degree of the graphite used in the present invention is not limited, but the above-described half-value width is suitably 0.4 or less, preferably 0.35 or less, more preferably 0.3 or less.

When the content of graphite increases with respect to the flame-resistant resin composition containing a thermoplastic resin, the flame-resistant resin composition, a sheet (single layer) comprising the composition, and the flame-resistant sheet of the present invention Increase the thermal conductivity. Therefore, the addition amount of graphite is, from one point of view, the thermal conductivity of the flame resistant resin composition, that is, the thermal conductivity when the flame resistant resin composition is a single layer is 0.5 W / m · K or more. It is suitable to add in the range. In order to impart higher flame retardancy, such as when used as an interior material for railway vehicles, it is preferably 2.2 W / m · K or more, more preferably 3.8 W / m · K or more, 6.1 W / M · K or more is more preferable.
When the flame resistant layer is laminated with other layers, etc., it has been confirmed that the thermal conductivity usually falls within a predetermined range depending on the material and thickness. Therefore, when decorating with laminates, such as a vinyl chloride resin, 4.6 W / m * K or more is especially preferable in the laminated structure.
The upper limit of the thermal conductivity is suitably 25 W / m · K or less, preferably 13 W / m · K or less, and more preferably 8 W / m · K or less.
In addition, since the content for obtaining the above-described thermal conductivity may vary depending on the type or state of graphite, for example, it is preferable to adjust graphite appropriately in consideration of the addition amount described later.

In the present invention, the thermal conductivity means a value measured as follows.
As an example of a method for producing a test piece, a resin composition is supplied to a twin screw extruder, melt-kneaded, and has a predetermined thickness (for example, 1 mm to several tens mm, specifically 3.2 mm). There is a way to get a sheet.
As another example, the resin composition is supplied to a kneader and melt-kneaded at a temperature of about 185 to obtain a sheet having a thickness of 1 mm. Next, the plurality of sheets are stacked and supplied to a hot press molding machine, and pressurized at a temperature of 190 and 20 MPa to obtain a 3.2 mm sheet.
The thermal conductivity is a value specific to the material, but may be affected by the base when the thickness of the measurement target layer is about 10 mm or less or in the case of a laminated structure. When the measurement target layer is about 10 mm or less or in the case of a laminated sheet, only the measurement target layer may be isolated and used as a test piece.
Then, the above-mentioned test piece is placed on a standard plate (silicon, quartz, zircon brick) having a known thermal conductivity in close contact with each other, and at room temperature, using a thermal conductivity meter, A probe is placed on the surface and the thermal conductivity is measured. Here, as the thermal conductivity meter, Chemtherm. QTM-D3 (trade name) (manufactured by Kyoto Electronics Industry Co., Ltd.) can be used.
Subsequently, the thermal conductivity of the standard plate and the deviation of the measured thermal conductivity are plotted, and the thermal conductivity is obtained from the intersection of the obtained straight line and the deviation = 0.

In the flame-resistant sheet of the present invention, in order to effectively develop the flame resistance, it is suitable to adjust the thermal conductivity of the above-mentioned flame-resistant layer to a predetermined range. It is preferable to consider the thickness of the combustion resistant layer in the thermal conductivity of the conductive layer.
The total thickness of the flame-resistant layer can be appropriately adjusted depending on the material, required characteristics, etc. in both a single layer and a laminated structure of two or more layers, and is not particularly limited. 1 mm or more. Moreover, 0.2 mm or more is suitable for the total thickness of a combustion-resistant layer, 0.8 mm or more is preferable and 2 mm or more is more preferable. If the total film thickness of the flame resistance is too small, the flame resistance tends to be hardly exhibited even if the thermal conductivity of the flame resistance layer is increased.
Therefore, the total thickness of the flame resistant layer contributing to heat dispersion is 0.2 mm or more, and [combustion resistant] defined by [thickness of the flame resistant layer] × [thermal conductivity of the flame resistant layer]. It is suitable to adjust the thermal conductivity of the layer] to 1.2 mW / K or more. Further, the thermal conductivity of the combustion resistant layer is preferably 2.9 mW / K or more, more preferably 5.2 mW / K, 9.1 mW / K or more, 11.0 mW / K, 14.3 mW / K. K or more is particularly preferable.
When the combustion resistant layer is composed of a plurality of layers having different thermal conductivities, [the amount of heat conduction of the combustion resistant layer] = [thickness of the first layer of the flame resistant layer] ] × [Thermal conductivity of the first flame-resistant layer] + [The thickness of the second flame-resistant layer] × [Thermal conductivity of the second flame-resistant layer] +. n thickness of the flame resistant layer] × [thermal conductivity of the nth flame resistant layer].

From another viewpoint, the amount of graphite added is preferably 10.0% by weight or more with respect to the total weight of the combustion-resistant resin composition. More preferably, it is 20.0 weight% or more, More preferably, it is 40.0 weight%. When decorating the surface layer with a laminate of a vinyl chloride resin or polyvinyl chloride, it is preferably 50% by weight, more preferably 59.1% by weight, and particularly preferably 65% by weight or more. If too much is added, the moldability may be deteriorated, so that it is preferably 80% by weight or less. More preferably, it is 70 weight% or less. Therefore, it is suitable to contain in 10 to 80 weight%, Preferably it is 15 to 70 weight%, 20 to 70 weight%, More preferably, it is 20 to 65 weight% or 35 to 70 weight%. By setting it as this range, while being able to acquire a suitable thermal conductivity and a flame-retardant effect, the fall of a moldability can be prevented.
In particular, the addition amount of graphite dominates the magnitude of the thermal conductivity as described above, but since it is also affected by the shape as described later, the manufacturing method of the flame resistant sheet, etc., the above described thermal conductivity is shown, And it is more preferable to adjust suitably in the range used as the addition amount mentioned above.

As a thermoplastic resin, it is a conventionally well-known thing, It does not specifically limit, A various thing can be used. However, the thermoplastic resin here excludes a resin generally functioning as a processing aid, particularly a processing aid described later. For example, polyolefin resin such as polypropylene resin and polyethylene resin; poly (1-) butene resin, polypentene resin, polycarbonate resin, polyphenylene ether resin, acrylic resin, styrene resin [for example, polystyrene (resistant Impact polystyrene), acrylonitrile-butadiene-styrene (ABS) resin, acrylonitrile-styrene (AS) resin, acrylonitrile-ethylene-propylene-styrene (AES) resin, acrylonitrile-acrylate-styrene (AAS) resin, etc.), polyamide Resin, chlorinated polyethylene, vinyl chloride resin, chlorinated vinyl chloride resin, ethylene copolymer [for example, ethylene-vinyl acetate copolymer, ethylene-methyl acrylate copolymer (EMA), Len - ethyl acrylate copolymer (EEA), ethylene - butyl acrylate copolymer (EBA), ethylenemethyl - methyl methacrylate copolymer (EMMA), and the like also like including] AES described above. These may be used alone or in combination of two or more. Among these, vinyl chloride resin with excellent combustion resistance and chlorine with excellent impact resistance and secondary processability can compensate for the decrease in impact resistance due to the addition of graphite and secondary processability such as vacuum formability. Preferred is a modified polyolefin. Further, when a vinyl chloride resin is used, the interlayer adhesion is further strengthened and advantageous in that a coating layer containing a vinyl chloride resin is laminated.
Although the molecular weight of the thermoplastic resin used by this invention is not specifically limited, For example, the weight average molecular weight of about 10,000-1 million is mentioned. This weight average molecular weight is a polystyrene-reduced weight average molecular weight measured by GPC (gel permeation chromatography) of a styrene elastomer (hereinafter, the same method for measuring the weight average molecular weight). In particular, in the method for measuring the weight average molecular weight of the (meth) acrylate polymer, it can be a value specifically measured under the following conditions. A calibration curve is prepared according to the molecular weight of polystyrene having a known molecular weight using an apparatus: HLC-8120 (manufactured by Tosoh Corporation), a solvent: THF. The column is appropriately selected depending on each molecular weight. For example, in the case of 3 million or more, use column: GMHHR-H (30) × 2 solvent: THF, sample concentration: 0.05%, injection amount: 50 μl, flow rate: 0.5 ml / min, depending on the molecular weight Adjust sample concentration.

  Vinyl chloride resin is a copolymer of vinyl chloride homopolymer (vinyl chloride homopolymer), a monomer having an unsaturated bond copolymerizable with vinyl chloride monomer, and vinyl chloride monomer (preferably containing 50% by weight or more). Examples thereof include a graft copolymer obtained by graft copolymerizing a vinyl chloride monomer with a polymer or a polymer. These polymers may be used alone or in combination of two or more.

  Examples of the monomer having an unsaturated bond copolymerizable with vinyl chloride monomer include α-olefins such as ethylene, propylene, and butylene; vinyl esters such as vinyl acetate and vinyl propionate; butyl vinyl ether, cetyl vinyl ether, and the like. Vinyl ethers; (meth) acrylic acid esters such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl acrylate, and phenyl methacrylate; aromatic vinyls such as styrene and α-methylstyrene; vinylidene chloride, vinylidene fluoride, etc. And halogenated vinyl vinyls; N-substituted maleimides such as N-phenylmaleimide and N-cyclohexylmaleimide; (meth) acrylic acid, maleic anhydride, acrylonitrile and the like. These may be used alone or in combination of two or more.

  The polymer for graft copolymerization of vinyl chloride resin is not particularly limited as long as the vinyl chloride resin is graft polymerized. For example, ethylene-vinyl acetate copolymer, ethylene-vinyl acetate-carbon monoxide copolymer , Ethylene-ethyl acrylate copolymer, ethylene-butyl acrylate-carbon monoxide copolymer, ethylene-methyl methacrylate copolymer, ethylene-propylene copolymer, acrylonitrile-butadiene copolymer, polyurethane, chlorinated polyethylene, chlorine And polypropylene. These may be used alone or in combination of two or more.

  The polymerization method of the vinyl chloride resin is not particularly limited, and any conventionally known polymerization method can be used. Examples thereof include a bulk polymerization method, a solution polymerization method, an emulsion polymerization method, and a suspension polymerization method.

  The chlorinated vinyl chloride resin may be polymerized using a material chlorinated before polymerization of the vinyl chloride monomer, or may be chlorinated after polymerizing the vinyl chloride resin. The method for chlorinating the vinyl chloride resin is not particularly limited, and a conventionally known chlorination method can be used. Examples thereof include a thermal chlorination method and a photochlorination method.

When the degree of polymerization of the vinyl chloride resin decreases, mechanical properties tend to decrease, and when it increases, moldability tends to deteriorate. Therefore, it is preferably about 400 to 2500, more preferably about 600 to 2000, 600 About 1600.
Examples of the method for adjusting the degree of polymerization mainly include the polymerization temperature. In general, the higher the polymerization temperature, the lower the degree of polymerization. The degree of polymerization can be measured according to JIS K 6720-2.

  Chlorinated polyolefins, such as chlorinated polyethylene, are chlorinated parts of polyethylene, and are generally used alone as elastomers with excellent flexibility, weather resistance, heat aging resistance, flame resistance, and chemical resistance. . Further, it is used as a physical property improver for general purpose resins such as vinyl chloride resin, olefin resin, ABS, or rubbers such as EPDM, chlorosulfonated polyethylene, chloroprene, SBR. Of these, chlorinated polyethylene is preferably used. Chlorinated polyethylene can be obtained using a conventionally known chlorination method.

When graphite is added to the resin component, the elastic modulus is remarkably increased and the entire composition becomes rigid, so that the elongation at high temperature required for impact resistance and secondary workability may be lowered. In particular, by using chlorinated polyethylene, the impact resistance reduced by graphite can be efficiently compensated by taking a network structure in a matrix that has become harder and brittle due to the addition of graphite and imparting flexibility, It is considered that the effect of improving elongation at high temperatures is exhibited.
The weight average molecular weight of about 50,000 to 400,000 is suitable for chlorinated polyethylene, and it is preferable that it is in a relatively high range (for example, about 320,000 or more). The degree of chlorination is suitably about 20% to 40%. Furthermore, it is preferable that the molecular weight is about 150,000 to 350,000 and the degree of chlorination is 25% to 36%.
In particular, when other resins are contained in the flame resistant resin composition, by setting the molecular weight within this range, it is possible to prevent other resins (for example, vinyl chloride resin, (meth) acrylate polymer, etc.). It is possible to improve the compatibility by developing entanglement at the molecular chain level. In addition, by relatively increasing the degree of chlorination (for example, about 34% or more), in particular, imparting a polarity close to that of other resins (for example, vinyl chloride resin, acrylic processing aids, etc.) and improving compatibility. It is thought that it can be made.

  The addition amount of the thermoplastic resin is not particularly limited, and is preferably adjusted as appropriate in consideration of the kind of the thermoplastic resin, secondary processability such as vacuum forming, moldability, and combustibility. For example, the thermoplastic resin is 1% by weight or more, preferably 5% by weight, more preferably 8% by weight or more, and particularly preferably 15% by weight or more based on the total flame-resistant resin composition. Moreover, as an upper limit, it is 85 weight% or less, Preferably it is 60 weight% or less, More preferably, it is 40 weight% or less, Most preferably, it is 30 weight% or less. If the amount added is too small, the physical properties tend to deteriorate. Moreover, when there is too much addition amount, since the quantity of graphite, other resin, etc. will reduce, combustibility and secondary workability may fall.

It is preferable that an acrylic processing aid for improving secondary processability is added to the flame resistant resin composition. In particular, the vacuum formability can be improved by adding an acrylic processing aid. The acrylic processing aid is also excellent in compatibility with various combustion-resistant resin compositions.
Examples of acrylic processing aids include (meth) acrylate polymers. The (meth) acrylate polymer is a general term for polymers mainly composed of acrylate monomers or methacrylate monomers, and serves as a processing aid.
For example, homopolymers or copolymers of (meth) acrylate monomers such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate; the above (meth) acrylate monomers and styrene, vinyltoluene, acrylonitrile And copolymers with other monomers. You may use these individually or in combination of 2 or more types.

The amount of the acrylic processing aid added can be appropriately adjusted in consideration of the amount of graphite added, secondary workability such as vacuum forming reduced by the addition of graphite, formability and combustibility.
In the flame resistant resin composition, when the graphite content is increased, it is necessary to increase the addition amount of the (meth) acrylate polymer for the purpose of preventing deterioration of moldability. On the other hand, in the case where decoration such as laminate of vinyl chloride resin is applied to the surface layer, or in order to determine that there is no ignition (incombustible) in the vehicle flammability test, the amount of graphite added (ratio to the composition) ) Must be increased, which limits the amount of (meth) acrylate polymer that can be added. Therefore, the addition amount of the (meth) acrylate polymer is 1% by weight or more, preferably 4% by weight, more preferably 12% by weight or more, and particularly preferably 23% by weight with respect to the total weight of the flame resistant resin composition. % Or more. Moreover, as an upper limit, it is 60 weight% or less, Preferably it is 40 weight% or less, 30 weight% or less. For example, 1-60 weight%, 4-40 weight%, 12-40 weight%, 12-30 weight% etc. are mentioned. By setting in this range, it is possible to achieve both improvement in combustion resistance due to the addition of graphite and secondary workability. If the amount added is too large, the amount (ratio) of the thermoplastic resin is decreased, and the physical properties are further deteriorated.

The vacuum forming of the flame resistant resin composition is generally performed by heating the surface temperature of the resin composition to about 180 ° C to 220 ° C. In such a high temperature state, the tension of the combustion-resistant resin composition, for example, polyvinyl chloride resin may be reduced and may be easily broken. Therefore, a (meth) acrylate polymer having a higher tension in the high temperature region is preferably used. When an inorganic material, particularly a non-spherical type inorganic material such as graphite, is added, it tends to break at a high temperature, so the addition of (meth) acrylate polymer is effective.
As the compound for improving elongation at high temperatures, thermoplastic elastomers such as NBR and Elvalloy, and plasticizers such as DOP can be used, but (meth) acrylate polymers are particularly preferred from the viewpoint of imparting tension at high temperatures.

  The weight average molecular weight of the (meth) acrylate polymer is not particularly limited. However, higher molecular weight is preferable from the viewpoint of higher tension at high temperature. For example, it is preferably 1 million or more, more preferably 3 million or more. On the other hand, if the molecular weight is too high, the moldability and physical properties are adversely affected. More preferably, it is 5 million or less.

It is preferable that an impact modifier excellent in impact resistance is added to the combustion resistant resin composition.
The impact modifier is not particularly limited as long as it is usually used in the field. For example, methyl methacrylate-butadiene-styrene graft copolymer (MBS resin), chlorinated polyethylene (CPE), ABS. Examples thereof include resins and acrylic modifiers. These may be used alone or in combination of two or more.
Here, the acrylic modifier is at least one acrylic copolymer selected from the group consisting of one of acrylic acid esters or methacrylic acid esters, in particular an acrylic component as a main component, and is crosslinked and spherical. The one that became. Among them, chlorinated polyethylene that can effectively compensate for the impact resistance reduced by graphite by adopting a network structure in a matrix that has become hard and brittle by the addition of graphite and imparting flexibility is suitably used. .
The amount of impact modifier added can be appropriately adjusted in consideration of the amount of graphite added, the type of impact modifier, and the like.

  In addition to the acrylic processing aid and / or impact modifier described above, various additives may be added to the flame resistant resin composition of the present invention. Examples of the additive include a flame retardant, a heat stabilizer, a stabilizing aid, a lubricant, an antioxidant, a light stabilizer, and a pigment for the purpose of assisting the combustion suppressing effect. You may use these individually or in combination of 2 or more types.

  Examples of the flame retardant include antimony oxide such as antimony dioxide, antimony trioxide, and antimony pentoxide, molybdenum compounds such as molybdenum trioxide, molybdenum disulfide, and ammonium molybdate, and bromines such as tetrabromobisphenol A and tetrabromoethane. Examples thereof include phosphorus compounds such as compounds, triphenyl phosphate, and ammonium polyphosphate.

  Examples of the heat stabilizer include dimethyltin mercapto, dibutyltin mercapto, dioctyltin mercapto, dibutyltin malate, dibutyltin malate polymer, dioctyltin malate, dioctyltin malate polymer, dioctyltin laurate, dibutyltin laurate, dibutyltin Organotin stabilizers such as laurate polymer, lead white, lead stearate, dibasic lead stearate, dibasic lead phosphite, basic lead sulfite, dibasic lead sulfite, tribasic lead sulfate, Lead stabilizers such as silica gel co-precipitated lead oxalate, lead benzoate, lead naphthenate, metal soap stabilizers such as calcium stearate, barium stearate, zinc stearate, calcium-zinc stabilizer, barium-zinc Stabilizer, barium-cadmium stabilizer, hydrotalcite, zeolite, etc. System stabilizer and the like.

  The stabilizing aid is not particularly limited, and examples thereof include epoxidized soybean oil, epoxidized linseed bean oil, epoxidized tetrahydrophthalate, epoxidized polybutadiene, and phosphate ester.

  The lubricant is not particularly limited, and examples thereof include montanic acid wax, paraffin wax, polyethylene wax, stearic acid, stearyl alcohol, and butyl stearate.

Examples of the antioxidant include phenol-based antioxidants, sulfur-based antioxidants, phosphite-based antioxidants, and the like.
The light stabilizer is not particularly limited, and examples thereof include ultraviolet absorbers such as salicylic acid esters, benzophenones, benzotriazoles, and cyanoacrylates, or hindered amine light stabilizers.
The pigment is not particularly limited, and examples thereof include organic pigments such as azo, phthalocyanine, selenium, and dye lakes, oxides, molybdenum chromate, sulfide / selenide, ferrocyanide, and the like. An inorganic pigment etc. are mentioned.

  The addition method and order of addition of the additive are not particularly limited, and can be any method and order. For example, the addition method is not particularly limited, and it can be added to the vinyl chloride resin by a hot blend method, a cold blend method, or the like.

The coating layer in the flame resistant sheet of the present invention is suitably formed by a thermoplastic resin composition containing a thermoplastic resin, and further includes a thermoplastic resin containing an impact modifier and / or a processing aid. It is preferably formed of a composition, and more preferably formed of a thermoplastic resin composition containing a thermoplastic resin, an impact modifier and a processing aid.
One or more thermoplastic resins and impact modifiers can be appropriately selected from those described above. Among them, as the thermoplastic resin, it is preferable to use a styrene resin and / or a vinyl chloride resin. The styrenic resin includes the above-described polymer alloys of the styrenic resin and other resins. For example, an alloy of polycarbonate resin and ABS resin (PC / ABS), an alloy of polycarbonate resin and AES resin (PC / AES), and the like can be given.
As the processing aid, the acrylic processing aid described above is preferable.
In this case, 1 to 30 parts by weight of the impact modifier is suitable for 100 parts by weight of the thermoplastic resin in consideration of improvement in impact resistance, heat resistance, mechanical strength, etc., preferably 3 ~ 20 parts by weight. The processing aid is suitable in an amount of 1 to 30 parts by weight, preferably 3 to 20 parts by weight in consideration of improvement in vacuum formability and surface smoothness of the sheet.

A preferred combination of an impact modifier and a processing aid is (MBS resin), a (meth) acrylate polymer having a weight average molecular weight of 1,000,000 to 6,000,000, chlorinated polyethylene (CPE), and a weight average molecular weight of 1,000,000 to 600. Examples include 10,000 (meth) acrylate polymers, acrylic impact modifiers, (meth) acrylate polymers having a weight average molecular weight of 1,000,000 to 6,000,000, or combinations thereof.
By setting it as such a structure, the flame-resistant sheet excellent in a flame retardance, a physical property, and secondary workability can be obtained.
Various additives may be added to the thermoplastic resin composition constituting the coating layer in the same manner as the combustion resistant resin composition.

  Note that, as described above, when the flame resistant sheet of the present invention is used for an interior material of a railway vehicle or the like, the surface exposed to the passenger side is referred to as the surface, but depending on the ignitability to the surface, etc. Flammability is evaluated. For example, a combustion test conducted by a method in accordance with Article 83 of Section 5 of the Fire Countermeasures for Vehicles in the Ministerial Ordinance (Ministry of Land, Infrastructure, Transport and Tourism Ordinance No. 151 on December 25, 2001) that establishes technical standards related to railway It becomes one of the indicators.

  The flame resistant sheet of the present invention can be formed by any method known in the art. For example, a flame resistant layer and a coating layer are separately formed into a sheet shape, and a method of laminating both, a method of forming either a flame resistant layer or a coating layer into a sheet shape, and applying the other raw material, A laminate integration method and the like can be mentioned by co-extrusion of the combustion resistant layer and the coating layer by a known method such as an inflation method or a T-die method.

The thickness of the flame resistant layer and the coating layer is not particularly limited, and can be any thickness.
The thicker the flame resistant layer, the greater the flame resistant effect, and the amount of graphite added can be suppressed. This is advantageous in terms of physical properties such as impact resistance and secondary workability such as vacuum formability.
The composition and thickness of the coating layer may be determined in accordance with the thickness of the combustion-resistant layer, the amount of graphite added, and the like, further taking into account the amount of heat conduction described above. Thereby, physical properties and secondary workability can be efficiently supplemented without impairing the combustion resistance.
When using the flame resistant sheet as an interior material for a railway vehicle or the like, it is preferable to dispose the coating layer on the back side of the flame resistant layer in order to efficiently develop the flame resistant effect. As described above, various functional layers such as a coating layer, printing, and a decorative layer can be provided on the surface. These coating layers and the like are preferably made of a highly flame retardant material (for example, vinyl chloride resin) in consideration of the flame resistance, and in a range not impairing the flame resistance, that is, against the flame resistance. It is preferable to set the thickness to a minimum so that the influence is reduced or the thermal conductivity is as high as possible within the above-described range. For example, the thickness of the covering layer or the like is about 3 mm or less, and is suitably suppressed to about 0.5 mm or less, preferably 0.05 to 0.3 mm.

Examples of the present invention will be described below, but the present invention is not limited to the following examples. In addition, unless otherwise indicated, the part and% in an Example show the value of a weight reference | standard. In addition, the composition of each component in the table indicates% by weight unless otherwise specified.
The materials used in Examples and Comparative Examples of the present invention are as follows.
(1) Vinyl chloride resin: manufactured by Tokuyama Sekisui Industry Co., Ltd., trade name “TS-800E”, degree of polymerization 800 (2) chlorinated polyethylene (CPE): manufactured by Dow Chemical Co., Ltd., trade name “Tyrin 3615P”
(3) Impact modifier: methyl methacrylate / butadiene / styrene copolymer (MBS), manufactured by Kaneka Corporation, trade name “M511”
(4) Processing aid ((meth) acrylate polymer):
Product name "Metbrene P-530A", manufactured by Mitsubishi Rayon Co., Ltd., molecular weight 3.1 million Product name "Metbrene P-570A", manufactured by Mitsubishi Rayon Co., Ltd., molecular weight 400,000 Product name "Metbrene P-501A", manufactured by Mitsubishi Rayon Co., Ltd., molecular weight 80 Product name “Metabrene P-551A”, manufactured by Mitsubishi Rayon Co., Ltd., molecular weight 1.5 million Product name “Kane Ace PA60”, product manufactured by Kaneka Co., Ltd., molecular weight 39.9 million (5) Thermal stabilizer: Product name “TVS # 1380” (Nitto Kasei Kogyo) (Made by company)
(6) Lubricant 1: HW220MP (trade name “Hiwax220MP”, manufactured by Mitsui Chemicals)
(7) Lubricant 2: Stearic acid (trade name “Lunac S30”, manufactured by Kao Corporation)
(8) Lubricant: G70S (trade name “LOXIOL G70S”, manufactured by Emery Oleo Chemicals Japan)
(9) Graphite:
Pyrolytic graphite (trade name “PC99-300M”, manufactured by Ito Graphite Co., Ltd., average particle size 42 μm)
Pyrolytic graphite (trade name “PC10”, manufactured by Ito Graphite Co., Ltd., average particle size 10 μm)
Pyrolytic graphite (trade name “PC60”, manufactured by Ito Graphite Co., Ltd., average particle size 30 μm)
Scale graphite (trade name “CFW18AK”, manufactured by Chuetsu Graphite Co., Ltd., average particle size: 18 μm)
Scale graphite (trade name “CFW100”, manufactured by Chuetsu Graphite Co., Ltd., average particle size: 100 μm)
Scale graphite (trade name “CFW300”, manufactured by Chuetsu Graphite Co., Ltd., average particle size: 300 μm)
Pulverized graphite after expansion (trade name “CS-F400”, manufactured by Maruho Casting Co., Ltd., average particle size 200 μm)
Artificial graphite (trade name “4443”, manufactured by ASBURY, average particle size 300 μm)
Scale graphite (trade name “F # 2”, manufactured by Nippon Graphite Industry Co., Ltd.)
(10) Ethylene-vinyl acetate copolymer (EVA): trade name “Evaflex EV-260”, manufactured by Mitsui DuPont Polychemical Co., Ltd. (vinyl acetate content 28 wt%)
(11) PC / ABS: (trade name “Techniace T-105”, manufactured by A & L Japan)
(12) Alkyl (meth) acrylate, tetrafluoroethylene mixture: Trade name “Methbrene A-3000”, manufactured by Mitsubishi Rayon Co., Ltd. (13) ABS resin:
Acrylonitrile-butadiene-styrene resin sheet, manufactured by Allen, trade name “ABS 556/499”
Product name “Clarastic GA-501”, manufactured by Nippon A & L (14) AES resin: Product name “Unibright UB-700A”, manufactured by Nippon A & L (15) Impact-resistant polystyrene sheet: Product name “FR HIPS”, Made by Allen Extruders, LLC

  A. Examples and Comparative Examples A predetermined amount (% by weight) of each component shown in Table 1 was supplied to a 20 L supermixer (manufactured by Kawata), and mixed by stirring to obtain a resin composition.

The obtained resin composition was supplied to an 8-inch mixing roll kneader (manufactured by Yasuda Seiki Co., Ltd.) and melt-kneaded at a temperature of 185 ° C. to obtain a roll sheet having a thickness of 1 mm.
Subsequently, it supplied to the hot press molding machine (made by Toho Machinery Co., Ltd.), and pressurized at the temperature of 190 degreeC and 20 Mpa, and obtained the B5 press sheet (combustion-resistant layer or coating layer) of the thickness described in Table 1.
Further, the combustion-resistant layer and the coating layer (back side) are overlaid, supplied to a hot press molding machine (manufactured by Toho Machinery Co., Ltd.), pressurized at a temperature of 190 ° C. and 20 MPa, and a B5 press having the thickness described in Table 1 A sheet was obtained (combustion resistant sheet).
In addition, the decoration layer supplies the obtained flame-resistant sheet and the laminate film made of vinyl chloride resin (thickness 120 μm) to a hot press molding machine (manufactured by Toho Machinery Co., Ltd.) and pressurizes at a temperature of 190 ° C. and 20 MPa. And formed on the surface of the flame resistant layer of the flame resistant sheet.

Next, impact resistance (notched Izod), tensile elongation at break, and vehicle combustion test were evaluated by the following methods.
<Impact resistance (notched Izod)>
The obtained B5 press sheet was cut to create a test piece, and measured at 23 ° C. according to ASTM D-256.

<Tensile fracture elongation>
(Dumbell production)
The obtained B5 press sheet was cut to produce a dumbbell having the same size as a tensile dumbbell shape cut out from a tube having a nominal diameter of 25 or less described in FIG. 1 of JIS K6741 (2004).
(Measurement)
A tensile test was performed at 130 ° C. in accordance with JIS K7113. The test machine was an autograph AGS-J manufactured by Shimadzu Corporation, the test speed was 500 mm / min, and the state adjustment was 2 hours.
(Calculation of tensile fracture elongation)
The distance between marked lines a (mm) was measured at 23 ° C. A tensile test was conducted until the dumbbell broke, the chuck moving distance before and after the tensile test was defined as b (mm), and b ÷ a × 100 (%) was defined as the tensile fracture elongation. Since the tensile fracture elongation at high temperature reflects secondary workability such as vacuum forming, this evaluation was used as a substitute evaluation method for vacuum forming.

<Vehicle combustion test>
Ignition: Evaluated in accordance with Article 83 of Section 5 on Fire Countermeasures for Vehicles in “Ministerial Ordinance Establishing Technical Standards on Railways (Ministry of Land, Infrastructure, Transport and Tourism No. 151 December 25, 2001)”.
All surfaces with which the alcohol flame comes into contact are from the side of the flame resistant layer.
Judgment criteria:
A: No ignition (equivalent to nonflammability)
○: Ignition time is 70 seconds or more and the fire after ignition is weak (equivalent to extremely flame retardant)
Δ: Ignition over 30 seconds and less than 70 seconds (equivalent to flame retardant)
X: Ignition within 30 seconds

B. Examples and Comparative Examples A predetermined amount (% by weight) of each component shown in Table 2 was supplied to a 20 L supermixer (manufactured by Kawata), and stirred and mixed to obtain a resin composition.

The obtained flame resistant resin composition is supplied to an SLM50 twin screw extruder (manufactured by Nagata Seisakusho), and further, a resin composition for a coating layer is supplied to a 40 mm single extruder, and melt kneaded at a resin temperature of 185 ° C. Then, a manifold two-layer mold was used to obtain a two-layered combustion resistant sheet.
In addition, the decoration layer supplies the obtained flame resistant sheet and each laminate film to a hot press molding machine (manufactured by Toho Machinery Co., Ltd.), pressurizes at a temperature of 190 ° C. and 20 MPa, and applies it to the surface of the flame resistant sheet. Formed.
The laminate films in Table 2 are as follows.
Lami (1) Vinyl chloride resin laminate film 120μm, thermal conductivity 0.2W / m · K
Lami (2) Acrylic resin laminate film 40μm, thermal conductivity 0.2W / m · K
Lami (3) Vinyl chloride resin laminate film 180μm, thermal conductivity 0.2W / m · K

Next, in the same manner as described above, impact resistance (notched Izod) and tensile elongation at break were measured, and a vehicle combustion test was performed.
The criteria for the tensile elongation at break were as follows.
◎: 130 ° C. tensile elongation at break of 400% or more ◎: 130 ° C. tensile elongation at break of 200% or more and less than 400% ○: 130 ° C. tensile elongation at break of 100% or more but less than 200% Δ: 130 ° C. tensile elongation at break 30% or more and less than 100% ×: 130 ° C. tensile fracture elongation is less than 30%

Further, the thermal conductivity and the average particle size of graphite in the molded body were evaluated by the following methods.
(Thermal conductivity)
The obtained sheet | seat was cut | disconnected and the sheet | seat of 150x100 mm was used as the test piece.
At room temperature, using a thermal conductivity meter (trade name Chemtherm. QTM-D3 (trade name) manufactured by Kyoto Electronics Industry Co., Ltd.) on a standard plate (silicon, quartz, zircon brick) whose thermal conductivity is known. The test pieces were brought into close contact with each other, and a probe was applied to the surface of the test piece (single layer) to measure the conductivity.
Specifically, when the thermal conductivity was 1.4 or more, the sample was brought into close contact with a quartz standard plate, and a probe was placed on the sample and allowed to stand for 2 minutes, followed by measurement. After the measurement, the probe was allowed to stand on an aluminum cooling plate for 2 minutes, and then the sample was brought into close contact with the zircon brick standard plate, and the probe was placed on the plate for 2 minutes to perform measurement.
Subsequently, when measuring another sample, the probe was left on the aluminum cooling plate for 15 minutes, and then the above operation was performed.
The deviation between the thermal conductivity of the standard plate and the measured thermal conductivity of the test piece was plotted, and the thermal conductivity was determined from the intersection of the obtained straight line and deviation = 0.
QTM-D3 (manufactured by Kyoto Electronics Industry) software was used for calculation of thermal conductivity.

(Average particle size of graphite in the compact)
30 mg of the obtained flame resistant sheet was dissolved in 30 g of THF (mass% concentration 0.1%), and the graphite was dispersed in the solution. The particle size distribution of the graphite was measured by a laser diffraction particle size distribution analyzer SALD-2200 (Shimadzu). Measured using a manufacturing plant). The table shows the volume average particle diameter (μm) of graphite.

C. Examples and Comparative Examples A predetermined amount (% by weight) of each component of the coating layer shown in Table 3 was supplied to a 20 L supermixer (manufactured by Kawata) and mixed by stirring to obtain a resin composition.

The obtained resin composition was supplied to an 8-inch mixing roll kneader (manufactured by Yasuda Seiki Co., Ltd.) and melt-kneaded at a temperature of 185 ° C. to obtain a roll sheet for a coating layer.
Similarly, a predetermined amount (% by weight) of each component of the flame resistant layer shown in Table 3 is supplied to an 8-inch mixing roll kneader (manufactured by Yasuda Seiki Co., Ltd.), melted and kneaded at a temperature of 170 ° C., and used for the flame resistant layer. Roll sheet was obtained.
Next, it is installed in a mold according to the thickness of each layer, supplied to a hot press molding machine (manufactured by Toho Machinery Co., Ltd.), pressurized at a temperature of 190 ° C. and 20 MPa, and a B5 size press sheet of each thickness shown in the table. Got. Each obtained flame-resistant layer and coating layer and decorative layer were overlaid and placed in a 3.5 mm thick formwork, supplied to a hot press molding machine (manufactured by Toho Machinery Co., Ltd.), temperature 190 ° C, A press sheet of B5 size was obtained by pressurizing at 20 MPa (three-layer sheet).
The decorative layer was a vinyl chloride resin laminate film having a thickness of 0.2 mm.
The comparative example was a single-layer B5 size press sheet in the same manner as described above.

  Next, impact resistance (notched Izod) and tensile elongation at break were measured in the same manner as described above, and a vehicle combustion test was performed in the same manner as described above.

D. Examples and Comparative Examples Predetermined amounts (% by weight) of each component shown in Table 4 were supplied to a 20 L super mixer (manufactured by Kawata) and mixed by stirring to obtain a resin composition.

The obtained resin composition was supplied to an 8-inch mixing roll kneader (manufactured by Yasuda Seiki Co., Ltd.) and melt-kneaded at a temperature of 185 to obtain a roll sheet.
Subsequently, it supplied to the hot press molding machine (made by Toho Machinery Co., Ltd.), and pressurized at the temperature of 190 and 20 MPa, and obtained the B5 press sheet of each thickness.
Combustion-resistant sheet having a decorative layer is composed of a combustion-resistant layer, a coating layer and a decorative layer, which are supplied to a hot press molding machine (manufactured by Toho Machinery Co., Ltd.), pressurized at 190 and 20 MPa, and a B5 press. A sheet was obtained (three-layer sheet).
In addition, the combustion-resistant layer and the coating layer were superposed, supplied to a hot press molding machine (manufactured by Toho Machinery Co., Ltd.), and pressurized at temperatures of 190 and 20 MPa to obtain a B5 press sheet (two-layer sheet).

  Next, impact resistance (notched Izod) and tensile elongation at break were measured in the same manner as described above, and a vehicle combustion test was performed in the same manner as described above.

E. Examples and comparative examples (combustion resistant layer)
A predetermined amount (% by weight) of each component shown in Table 5 was supplied to an 8-inch mixing roll kneader (manufactured by Yasuda Seiki Co., Ltd.) and melt-kneaded at a temperature of 170 ° C. to obtain a roll sheet. Subsequently, it supplied to the hot press molding machine (made by Toho Machinery Co., Ltd.), pressurized at 190 degreeC and 20 Mpa, and obtained the B5 press sheet of the thickness described in Table 5.
(Coating layer: ABS, AES)
The raw material resin was supplied to an 8-inch mixing roll kneader (manufactured by Yasuda Seiki Co., Ltd.) and melt-kneaded at a temperature of 190 ° C. to obtain a roll sheet. Subsequently, it supplied to the hot press molding machine (made by Toho Machinery Co., Ltd.), pressurized at 190 degreeC and 20 Mpa, and obtained the B5 press sheet of the thickness described in Table 5.
(Coating layer: PC / ABS alloy)
The raw material resin was supplied to an 8-inch mixing roll kneader (manufactured by Yasuda Seiki Co., Ltd.) and melt-kneaded at a temperature of 220 ° C. to obtain a roll sheet. Subsequently, it supplied to the hot press molding machine (made by Toho Machinery Co., Ltd.), pressurized at 220 degreeC and 20 Mpa, and obtained the B5 press sheet of the thickness described in Table 1.
(Coating layer: impact-resistant polystyrene sheet)
Sheet molded products having a thickness of 1 mm and 3.5 mm were used.
(Production of laminate)
The decorative layer, the combustion resistant layer and the coating layer described in Table 5 are superposed, supplied to a hot press molding machine (manufactured by Toho Machinery Co., Ltd.), pressurized at 190 ° C. and 20 MPa, and B5 having a thickness of 3.5 mm. A press sheet was obtained (three-layer sheet). The decorative layer was an acrylic resin laminate film having a thickness of 0.2 mm.

  Next, impact resistance (notched Izod) and tensile elongation at break were measured in the same manner as described above, and a vehicle combustion test was performed in the same manner as described above.

  The flame-resistant sheet of the present invention has various functionalities in addition to various fields that require flame resistance, for example, interior materials for vehicles and the like, in particular, interior materials for railway vehicles, automobiles, airplanes, and the like. It can be suitably used as a functional sheet or the like.

Claims (5)

A combustion resistant sheet comprising a combustion resistant layer composed of a flame resistant resin composition and a coating layer,
The flame resistant layer is formed of a flame resistant resin composition containing a thermoplastic resin and graphite, and is defined by [thickness of the flame resistant layer] × [thermal conductivity of the flame resistant layer]. The thermal conductivity of the layer] is 3.4 mW / K or more,
A combustion-resistant sheet, wherein the coating layer is formed of a thermoplastic resin composition. A combustion resistant sheet comprising a combustion resistant layer composed of a flame resistant resin composition and a coating layer,
The flame resistant layer is formed of a flame resistant resin composition comprising a thermoplastic resin and graphite;
The graphite is contained in an amount of 35.9% by weight or more based on the total amount of the flame resistant resin composition, and the flame resistant layer has a thermal conductivity of 1.4 W / m · K or higher. And
A combustion-resistant sheet, wherein the coating layer is formed of a thermoplastic resin composition . The flame-resistant sheet according to claim 1 or 2, wherein the flame-resistant layer is formed of a flame-resistant resin composition further containing an acrylic processing aid. The combustion-resistant sheet according to any one of claims 1 to 3, wherein the coating layer is formed of a thermoplastic resin composition containing a vinyl chloride resin containing an impact modifier and a processing aid. The combustion-resistant sheet according to any one of claims 1 to 4 , wherein the coating layer is formed of a thermoplastic resin composition containing a styrene resin.