JP7101141B2 - Manufacturing method of drainage piping material, piping structure and drainage piping material - Google Patents

Description

The present invention relates to a piping material, a piping structure, and a method for manufacturing a piping material installed inside a building such as an apartment house.

In a building such as an apartment house, the adjacent upper and lower floors are separated by floor slabs, and on each floor, two adjacent rooms are separated by walls and partitioned. A piping structure for draining or supplying water is installed inside the building, and a through hole through which the piping structure is passed through the floor slab and the wall (in this specification, this through hole is referred to as a partition penetration portion). .) Is formed.
As the piping structure passed through the section penetration portion of the floor slab, for example, the first vertical pipe (pipe material) installed in the vertical direction on the lower floor with respect to the floor slab and the floor slab. A second vertical pipe (piping material) installed in the vertical direction on the upper floor, a horizontal branch pipe (piping material) installed on the upper side of the floor slab, and a receptacle for connecting each pipe were provided. Those provided with a three-way pipe joint can be mentioned. In such a piping structure, the upper end portion of the first vertical pipe is connected to the receiving port of the pipe joint in the partition penetrating portion formed in the floor slab. Further, a sealing material such as mortar is filled between the inner surface of the section penetrating portion and the pipe joint to fill the gap between the inner surface of the section penetrating portion and the pipe joint.

If a fire breaks out in a building where the above piping structure is installed, flames, heat and smoke will rise from the floor where the fire is occurring to the floor above it through the section penetration, causing physical damage. And may increase human damage. Therefore, in general, in the piping structure, fire resistance measures are taken to shield flames, heat and smoke at the section penetrating portion in the event of a fire.
As a fire resistance measure in a pipe structure, a method of including heat-expandable graphite in a pipe material inserted into a section penetrating portion is known (Patent Document 1). When the piping material contains heat-expandable graphite, when a fire occurs and the heat rises, the piping material expands due to the heat and the partition penetrating portion can be closed. Therefore, flames, heat and smoke can be prevented from rising through the compartment penetration.

By the way, when producing a piping material, it is necessary to heat and melt the resin forming the piping material to form the piping material. However, if the thermal expansion start temperature of the heat-expandable graphite contained in the piping material is low, the heat-expandable graphite may expand during the production of the piping material, so that it is difficult to produce the piping material. Therefore, as the thermally expandable graphite contained in the piping material, it is preferable that the thermal expansion start temperature is higher than the heating temperature of the resin at the time of producing the piping material, for example, 240 ° C. or higher.

Japanese Patent No. 4829847

However, when the thermal expansion start temperature of the piping material is increased by containing the thermal expansion graphite having a high thermal expansion start temperature in the piping material, the thermal expansion start of the piping material is delayed when a fire occurs. There is a tendency. Therefore, it is conceivable that the pipe joint above the pipe material is heated by the heat of the fire and is deformed or melted before the partition penetrating portion is closed by the expansion of the pipe material. When the pipe joint is deformed, it is expected that a gap will be formed between the pipe joint and the sealing material filled around the pipe joint. The gap can cause flames, heat and smoke to rise from the lower floors to the upper floors. When the pipe joint is melted, it is predicted that it will be difficult to connect the piping material, the piping material will fall, and it will be difficult to close the section penetrating portion due to the expansion of the piping material.
In the present invention, although the thermal expansion start temperature of the piping material is high and it is easy to manufacture the piping material, the deformation of the pipe joint can be suppressed in the event of a fire, and the partition penetration portion is surely closed by the expansion of the piping material. The purpose is to provide a possible piping structure.

One aspect of the piping material of the present invention is a piping material having a multi-layer structure having at least a surface layer, an intermediate layer, and an inner layer, and the surface layer and the inner layer are made of a polyvinyl chloride resin and a colorant other than black. The intermediate layer contains a polyvinyl chloride resin and a heat-expandable graphite, and the heat-expandable graphite has a heat expansion start temperature of 240 ° C. or higher, and the heat expansion in the middle layer. The content of the sex graphite is 10.0 parts by mass or more and 28.0 parts by mass or less with respect to 100 parts by mass of the polyvinyl chloride resin in the intermediate layer.
In the piping material of this embodiment, the intermediate layer contains at least one heat-dehydrated compound selected from aluminum hydroxide and magnesium hydroxide, and the content of the heat-dehydrated compound is the polychloride of the intermediate layer. It is preferably 0.1 parts by mass or more and 20.0 parts by mass or less with respect to 100 parts by mass of the vinyl resin.
In the piping material of this embodiment, the average aspect ratio of the heat-expandable graphite is preferably 30 or less.
In the piping material of this embodiment, it is preferable that the coefficient of linear expansion defined by JIS K 7197 is 4.5 × 10 ^-5 / ° C. or higher and less than 7.0 × 10 ^-5 / ° C.
In the piping material of this embodiment, the fusion strength between the inner layer and the intermediate layer is preferably 0.8 MPa or more.
One aspect of the piping structure of the present invention is a piping structure comprising a transparent pipe joint provided with a socket and the above-mentioned piping material of the present invention, wherein at least the piping material is located in a section penetration portion of a floor slab. The pipe joint contains a resin composition containing a polyvinyl chloride resin and a heat absorbing agent, and the heat absorbing agent has a volume average particle diameter of 0.01 μm or more and 20 μm or less, and is different from the pipe joint. The piping material is joined with an adhesive to which a colorant or a light emitting agent is added.
One aspect of the piping structure of the present invention is a piping structure in which an upper pipe joint and a lower pipe joint and the above-mentioned piping material of the present invention are previously joined, and the upper pipe joint is the pipe material of the above. The lower pipe joint is provided with a receptacle to which the upper end can be connected, and the lower pipe joint is provided with a receptacle to which the lower end of the piping material can be connected. Both or one of the connection portion between the piping material and the socket of the upper pipe joint and the connection portion between the piping material and the socket of the lower pipe joint are of the floor slab. It is located in the section penetration.
In the piping structure of this embodiment, the piping material protrudes downward from the floor slab, and the connection portion between the piping material and the receiving port of the upper pipe joint is located in the compartment penetration portion of the floor slab. The connection portion between the piping material and the receiving port of the lower pipe joint is preferably located outside the partition penetrating portion of the floor slab.
One aspect of the piping structure of the present invention is a piping structure comprising a pipe joint provided with a spout and the above-mentioned piping material of the present invention, wherein at least the piping material is located in a section penetration portion of a floor slab. The pipe material is provided with a receiving port at an end portion, and the outlet of the pipe joint is inserted into the receiving port of the piping material.
One aspect of the piping structure of the present invention is a method for manufacturing a piping material having a multi-layer structure having at least a surface layer, an intermediate layer, and an inner layer, and the surface layer and the inner layer are colored other than polyvinyl chloride resin and black. The intermediate layer contains a polyvinyl chloride resin, a heat-expandable graphite, and at least one heat-dehydrateable compound selected from aluminum hydroxide and magnesium hydroxide, and the heat-dehydrated layer in the intermediate layer. The content of the type compound is 0.3 parts by mass or more and 3 parts by mass or less with respect to 100 parts by mass of the polyvinyl chloride resin of the intermediate layer, and the heat-expandable graphite has a heat expansion start temperature of 240 ° C. or more. In addition, the pH is 1.0 or more and 7.0 or less, and the surface layer, the intermediate layer, and the inner layer are laminated and extruded with a three-layer extrusion mold, and then introduced into a sizing sleeve to shape the outer surface. do.

In the piping structure of the present invention, although the thermal expansion start temperature of the piping material is high and it is easy to manufacture the piping material, the deformation of the pipe joint can be suppressed in the event of a fire, and the partition penetration portion due to the expansion of the piping material. Can be reliably closed.

It is sectional drawing which shows one Embodiment of the piping structure of this invention. It is a schematic block diagram which shows an example of the manufacturing apparatus which manufactures the piping material of a three-layer structure. It is sectional drawing which shows an example of the mold provided in the manufacturing apparatus of FIG. It is a schematic diagram which shows an example of the vacuum sizing apparatus provided in the manufacturing apparatus of FIG. (A) is a partial cross-sectional view schematically showing an example of the state of the end portion of the piping material (pipe) inserted into the receiving port of the pipe joint, and (b) is the pipe inserted into the receiving port of the pipe joint. It is a partial cross-sectional view schematically showing another example of the state of the end part of a material (pipe). It is sectional drawing which shows the state when the fire breaks out in the building in the piping structure of FIG. It is sectional drawing which shows the other embodiment of the piping structure of this invention. It is sectional drawing which shows the universal tester used in the evaluation of an Example and a comparative example. It is sectional drawing which shows the refractory test furnace used in the evaluation of an Example and a comparative example.

An embodiment of the piping structure of the present invention will be described.
As shown in FIG. 1, the pipe structure 1 of the present embodiment is used as a drainage channel and includes a pipe joint 10 and a pipe material 20. The piping structure 1 of the present embodiment is installed by being passed through a partition penetrating portion 2a formed in a floor slab 2 that partitions adjacent upper and lower floors. The mortar 3 is filled between the pipe structure 1 and the inner side surface of the section penetrating portion 2a to fill the gap between the inner side surface of the section penetrating portion 2a and the pipe joint 10, and the pipe structure. 1 is fixed.

(Pipe fitting)
The pipe joint 10 in the present embodiment includes a main pipe portion 11 and a lateral branch pipe connecting portion 12 provided in the main pipe portion 11.
At both ends of the main pipe portion 11, receiving ports 11a and 11b for connecting the piping material 20 (the first standing pipe 21 and the second standing pipe 22 described later) are provided, and the lateral branch pipe connecting portion is provided. At the end of 12, a receiving port 12a for connecting a piping material 20 (a horizontal branch pipe 23 described later) is provided. The inner peripheral surface of the receiving port 11a has an inner diameter that the outer peripheral surface of the piping material 20 (first standing pipe 21) is in close contact with, and the inner peripheral surface of the receiving port 11b is the piping material 20 (second standing pipe 21). The inner peripheral surface of the pipe 22) is set to have an inner diameter in which the outer peripheral surface of the pipe material 20 (horizontal branch pipe 23) is in close contact with the inner peripheral surface of the receiving port 12a.
In the present embodiment, the main portion 11 is composed of a straight pipe. The lateral branch pipe connecting portion 12 has a shape in which the vicinity of the main pipe portion 11 is curved toward the receiving port 11a in order to facilitate the flow of drainage flowing inside the lateral branch pipe connecting portion 12.
On the inner peripheral surface of each of the receiving ports 11a, 11b, 12a, a packing that is in close contact with the outer peripheral surface of the pipes 21, 22, 23 and is made watertight may be attached.

The pipe joint 10 contains a resin composition (A) containing a polyvinyl chloride resin and an endothermic agent. That is, the pipe joint 10 is manufactured by molding the resin composition (A). Usually, the pipe joint 10 is manufactured by injection molding the resin composition (A).
The pipe joint 10 may have a single-layer structure in which the entire pipe joint 10 is made of the resin composition (A), or may be a multi-layer structure including a plurality of layers. In the case of a multi-layer structure, any layer may be formed from the resin composition (A). For example, when the pipe joint 10 has a three-layer structure including a surface layer, an intermediate layer, and an inner layer, the intermediate layer may be formed from the resin composition (A).
The resin composition (A) constituting the pipe joint 10 preferably does not contain thermally expandable graphite.

[Resin composition (A)]
Examples of the polyvinyl chloride-based resin contained in the resin composition (A) include a polyvinyl chloride homopolymer; a vinyl chloride monomer and another monomer having an unsaturated bond copolymerizable with the vinyl chloride monomer. Copolymer: A graft copolymer obtained by graft-copolymerizing a vinyl chloride monomer to a polymer other than a polyvinyl chloride resin can be mentioned. The polyvinyl chloride resin may be used alone or in combination of two or more.
The polyvinyl chloride resin may be further chlorinated. Examples of the chlorination method for the polyvinyl chloride resin include a thermal chlorination method and a photochlorination method.

Examples of other monomers having an unsaturated bond copolymerizable with the vinyl chloride monomer include α-olefins such as ethylene, propylene and butylene; vinyl esters such as vinyl acetate and vinyl propionate; butyl vinyl ether and cetyl. Vinyl ethers such as vinyl ethers; (meth) acrylic acid esters such as methyl (meth) acrylate, ethyl (meth) acrylate and butyl acrylate; aromatic vinyls such as styrene and α-methylstyrene; N-phenylmaleimide, N- Examples thereof include N-substituted maleimides such as cyclohexylmaleimide. The other monomers may be used alone or in combination of two or more.

Examples of the polymer for graft-copolymerizing the vinyl chloride monomer include ethylene-vinyl acetate copolymer, ethylene-vinyl acetate-carbon monoxide copolymer, ethylene-ethyl acrylate copolymer, and ethylene-butyl acrylate-1. Examples thereof include a carbon oxide copolymer, an ethylene-methylmethacrylate copolymer, an ethylene-propylene copolymer, an acrylonitrile-butadiene copolymer, a polyurethane, a chlorinated polyethylene, and a chlorinated polypropylene. One of these polymers may be used alone, or two or more of them may be used in combination.

The polyvinyl chloride resin may be crosslinked. Examples of the method for cross-linking the polyvinyl chloride resin include a method of adding a cross-linking agent and a peroxide, a method of irradiating an electron beam, and a method of using a water-crosslinkable material.

The average degree of polymerization of the polyvinyl chloride resin is preferably 400 or more and 1600 or less, and more preferably 600 or more and 1400 or less. Here, the average degree of polymerization is determined by using a resin obtained by dissolving a polyvinyl chloride resin in tetrahydrofuran (THF), removing insoluble components by filtration, and then drying and removing THF in the filtrate as a sample. It is an average degree of polymerization measured according to 6721 "vinyl chloride resin test method".
When the average degree of polymerization of the polyvinyl chloride resin is at least the lower limit value, the mechanical strength can be sufficiently increased, and when it is at least the upper limit value, sufficient moldability can be ensured.

The endothermic agent contained in the resin composition (A) is a compound that has an endothermic action and suppresses a temperature rise when heated. For example, a compound that causes an endothermic reaction such as a dehydration reaction when heated can be used as an endothermic agent.
Examples of compounds that undergo a dehydration reaction when heated include inorganic hydroxides such as magnesium hydroxide, aluminum hydroxide, kaolin-based minerals (kaolinite, halloysite, and dikite) and hydrotalsalsite, sepiolite, and bentonite. Examples thereof include water-absorbing inorganic compounds such as montmorillonite, talc, mica, quartz, zeolite, wallastonite, and neferin sialite. Hereinafter, inorganic hydroxides and inorganic compounds that undergo a dehydration reaction when heated are collectively referred to as "heat dehydration type compounds". In the heat-dehydration type compound, the temperature rise can also be suppressed by the latent heat of vaporization of water generated by the dehydration reaction.
Of the heat-dehydration type compounds, magnesium hydroxide causes a dehydration reaction at 300 ° C. or higher. Therefore, when magnesium hydroxide is used as a heat absorbing agent, the resin composition (A) is molded to produce a pipe joint 10. It is possible to suppress the occurrence of dehydration reaction.
Of the heat-dehydration type compounds, aluminum hydroxide causes a dehydration reaction at about 200 ° C. Therefore, when aluminum hydroxide is used as a heat absorbing agent, the heat transferred to the pipe joint 10 in the event of a fire is absorbed early. be able to. Therefore, it is possible to further prevent the pipe joint 10 from being deformed and impairing the fire resistance before the piping material 20 (first vertical pipe 21) is thermally expanded.

Among the heat-dehydrated compounds, hydrotalcite is a kind of mineral represented by Mg ₆ Al ₂ (OH) ₁₆ CO _{3.4H 2} O, etc., whose chemical name is magnesium, aluminum, hydroxide, carbonate, hydrate. Yes, a layered inorganic compound consisting of a positively charged basic layer [Mg _1-x Al _x (OH) ₂ ] ^{x +} and a negatively charged intermediate layer [(CO ₃ ) _{x / 2} · mH ₂ O] ^x- . be. Many divalent and trivalent metals have a similar layered structure, and these are expressed by the following general formulas.
[M ²⁺ _1-x M ³⁺ _x (OH) ₂ ] ^{x +} [An- _{x / n} ^・mH ₂ O] ^x-
M ²⁺ : Divalent metal ions such as Mg ²⁺ and Zn ²⁺ M ³⁺ : Trivalent metal ions such as Al ³⁺ and Fe ³⁺ An-: CO ₃ ^2- , ^Cl- , NO _3- ^and other ⁿ -valent anions X: 0 <X ≦ 0.33
In hydrotalcite, the water of crystallization between the molecules starts dehydration at about 180 ° C, and the water of crystallization is completely desorbed at about 300 ° C. Until this state, the synthetic hydrotalcite retains its crystal structure, but when the temperature exceeds about 350 ° C, the crystal structure begins to collapse and releases water and carbon dioxide. Since the synthetic hydrotalsite starts endothermic decomposition at a temperature 60 ° C. or higher and 75 ° C. or lower lower than the thermal decomposition temperature of about 200 ° C. or higher and 300 ° C. or lower, which is the thermal decomposition temperature of the vinyl chloride resin, the thermal decomposition of the vinyl chloride resin is performed. Can be efficiently suppressed by endothermic decomposition of hydrotalcite.
As the endothermic agent, at least two kinds of magnesium hydroxide, aluminum hydroxide, kaolin-based mineral or hydrotalcite may be used in combination.

The heat-dehydrated compound is usually in the form of particles.
The volume average particle size of the heat-dehydrated compound is preferably 0.01 μm or more and 20 μm or less, more preferably 0.05 μm or more and 2 μm or less, and further preferably 0.05 μm or more and 1 μm or less. By setting the volume average particle size of the heat-dehydrated compound in this range, transparency can be imparted to the pipe joint 10 and the dispersibility of the heat-dehydrated compound can be improved. The volume average particle size is a value measured using a laser diffraction / scattering method particle size distribution measuring device.
The BET specific surface area of the heat-dehydrated compound is preferably 1 m ² / g or more and 40 m ² / g, and preferably 1 m ² / g or more and 20 m ² / g or less. Here, the BET specific surface area is a value obtained by utilizing nitrogen adsorption.
When the volume average particle size and the BET specific surface area of the heat-dehydrated compound are within the above ranges, the effect as a heat absorbing agent can be sufficiently exerted, and the moldability of the resin composition (A) when manufacturing the pipe joint 10 is achieved. And the mechanical properties of the pipe joint 10 can be sufficiently ensured.

It is preferable that the surface of the particles of the heat-dehydrated compound is surface-treated with a higher fatty acid such as stearic acid or a surface treatment agent such as a silane coupling agent. The heat-dehydrated compound surface-treated with a surface-treating agent has high dispersibility in a polyvinyl chloride-based resin, and is more likely to exert an endothermic effect. Further, when the heat-dehydrated compound is basic, the polyvinyl chloride-based resin can be prevented from being burnt and yellowing can be prevented.
When the heat-dehydrated compound is surface-treated with a surface treatment agent, the amount of the surface treatment agent is preferably 0.05 parts by mass or more and 2.0 parts by mass or less with respect to 100 parts by mass of the heat-dehydrated compound. When the amount of the surface treatment agent is at least the above lower limit value, the dispersibility of the heat-dehydrated compound with respect to the polyvinyl chloride resin can be sufficiently increased, and when it is at least the above upper limit value, the decrease in economic efficiency can be suppressed.

The content of the heat absorbing agent in the resin composition (A) is preferably 0.01 parts by mass or more and 10.0 parts by mass or less, and 0.05 parts by mass or more and 5 parts by mass with respect to 100 parts by mass of the polyvinyl chloride resin. It is more preferably 0.0 parts by mass or less, and further preferably 0.1 parts by mass or more and 2.0 parts by mass or less. If the content of the heat absorbing agent in the resin composition (A) is not less than the lower limit value, the deformation of the pipe joint 10 can be further suppressed in the event of a fire, and if it is not more than the upper limit value, the pipe joint 10 is manufactured. The formability can be sufficiently improved, and the mechanical properties of the pipe joint 10 can be improved.

The resin composition (A) may contain a flame retardant other than the endothermic agent as long as the effects of the present invention are not impaired.
Other flame retardants include antimony oxides such as hydrotalcite, antimony dioxide, antimony trioxide, antimony pentoxide; molybdenum compounds such as molybdenum trioxide, molybdenum disulfide, ammonium molybdate; tetrabromobisphenol A, tetrabromuethane. , Tetrabromuetane, tetrabromuetane and other bromine-based compounds; triphenylphosphate, ammonium polyphosphate and other phosphorus-based compounds; calcium borate, zinc borate and other borate-based compounds. Among the other flame retardants, antimony trioxide is preferable because it has a high effect of suppressing the combustion of polyvinyl chloride.

Further, the resin composition (A) contains a lubricant, a processing aid, an impact modifier, a heat improver, an antioxidant, a heat stabilizer, a heat stabilization aid, and the like, as long as the effects of the present invention are not impaired. Additives such as light stabilizers, UV absorbers, pigments, plasticizers, thermoplastic elastomers and the like may be included.
As each additive described later, one kind may be used alone, or two or more kinds may be used in combination.

Examples of the lubricant include an internal lubricant and an external lubricant.
Examples of the internal lubricant include butyl stearate, lauryl alcohol, stearyl alcohol, epoxidized soybean oil, glycerin monostearate, stearic acid, bisamide and the like.
Examples of the external lubricant include paraffin wax, polyolefin wax, ester wax, montanic acid wax and the like.

Examples of the processing aid include an alkyl acrylate-alkyl methacrylate copolymer having a mass average molecular weight of 100,000 or more and 2 million or less. Examples of the alkyl acrylate-alkyl methacrylate copolymer include an n-butyl acrylate-methyl methacrylate copolymer, a 2-ethylhexyl acrylate-methyl methacrylate-butyl methacrylate copolymer and the like.

Examples of the impact modifier include methyl methacrylate-butadiene-styrene copolymer (MBS), chlorinated polyethylene, acrylic rubber and the like.
Examples of the heat resistance improving agent include α-methylstyrene resin and N-phenylmaleimide resin.

Examples of the antioxidant include a phenol-based antioxidant, a phosphorus-based antioxidant, and the like.

Examples of the heat stabilizer include lead-based stabilizers, tin-based stabilizers, Ca—Zn-based stabilizers, higher fatty acid metal salts, and the like. One type of heat stabilizer may be used alone, or two or more types may be used in combination.
Examples of lead-based stabilizers include lead white, basic lead sulfite, tribasic lead sulfate, dibasic lead phosphite, dibasic lead phthalate, tribasic lead maleate, and silica gel co-precipitated silicic acid. Examples thereof include lead, dibasic lead stearate, lead stearate, lead naphthenate and the like.
Examples of the tin-based stabilizer include mercaptides such as dibutyl tin mercapto, dioctyl tin mercapto, and dimethyl tin mercapto; malates such as dibutyl tin malate, dibutyl tin malate polymer, dioctyl tin malate, and dioctyl tin malate polymer; dibutyl. Examples thereof include carboxylates such as tin mercaptodibutyl tin laurate and dibutyltin laurate polymer.
The Ca—Zn-based stabilizer is a mixture of a fatty acid salt of calcium and a fatty acid salt of zinc. Examples of the fatty acid include behenic acid, stearic acid, lauric acid, oleic acid, palmitic acid, ricinoleic acid, benzoic acid and the like, and two or more of these may be used in combination.
Examples of the higher fatty acid metal salt include lithium stearate, magnesium stearate, calcium stearate, calcium laurate, calcium lysinorate, strontium stearate, barium stearate, barium laurate, barium lysinolate, cadmium stearate, and cadmium laurate. , Cadmium lysinolate, cadmium naphthenate, cadmium 2-ethylhexoate, zinc stearate, zinc laurate, zinc lysinolate, zinc 2-ethylhexoate, lead stearate, lead dibasic stearate, lead naphthenate, etc. Be done.
Among these, tin-based stabilizers or Ca—Zn-based stabilizers are preferable for making the pipe joint 10 transparent, and as tin-based stabilizers, sulfur-free substances such as malates and carboxylates are sulfide-contaminated. The Ca—Zn-based stabilizer is particularly preferably stearate because of the balance between slipperiness during molding and plate-out.

The content of the heat stabilizer is preferably 0.3 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the polyvinyl chloride resin. If the content of the heat stabilizer is at least the above lower limit, the thermal stability of the polyvinyl chloride resin at the time of molding can be improved, and if it is at least the above lower limit, the polyvinyl chloride resin at the time of combustion can be improved. Can be sufficiently carbonized, and sufficient fire resistance can be obtained.

Examples of the heat stabilizing aid include epoxidized soybean oil, phosphoric acid ester, polyol, hydrotalcite, zeolite and the like.
Examples of the light stabilizer include hindered amine-based light stabilizers.
Examples of the ultraviolet absorber include a salicylic acid ester-based ultraviolet absorber, a benzophenone-based ultraviolet absorber, a benzotriazole-based ultraviolet absorber, and a cyanoacrylate-based ultraviolet absorber.

Examples of the pigment include azo pigments, phthalocyanine pigments, slene pigments, dye lake-based organic pigments; oxide pigments, molybdenum chromate pigments, sulfide / selenium pigments, and ferrosinide pigments. Inorganic pigments such as.

Examples of the plasticizer include dibutyl phthalate, di-2-ethylhexyl phthalate, di-2-ethylhexyl adipate and the like. However, since the plasticizer tends to reduce the heat resistance and the fire resistance of the molded product, it is preferable that the amount of the plasticizer used is small.

Examples of the thermoplastic elastomer include acrylonitrile-butadiene copolymer (NBR), ethylene-vinyl acetate copolymer (EVA), ethylene-vinyl acetate-carbon monoxide copolymer (EVACO), and vinyl chloride-vinyl acetate. Vinyl chloride-based thermoplastic elastomers such as polymers and vinyl chloride-vinylidene chloride copolymers, styrene-based thermoplastic elastomers, olefin-based thermoplastic elastomers, urethane-based thermoplastic elastomers, polyester-based thermoplastic elastomers, polyamide-based thermoplastic elastomers, etc. Can be mentioned.

(Piping material)
The piping material 20 in the present embodiment is a first vertical pipe 21, a second vertical pipe 22, and a horizontal branch pipe 23.
The first vertical pipe 21 is arranged vertically with respect to the floor slab 2 and its upper end is connected to the lower receiving port 11a of the pipe joint 10. The upper end of the first vertical pipe 21 is inserted into the compartment penetrating portion 2a.
The second vertical pipe 22 is arranged vertically with respect to the floor slab 2 and its lower end is connected to the upper receiving port 11b of the pipe joint 10.
One end of the lateral branch pipe 23 is connected to the receiving port 12a of the lateral branch pipe connecting portion 12, and is arranged so as to be inclined so as to gradually increase as the distance from the receiving port 12a increases. However, since the installation space of the horizontal branch pipe 23 is limited, the inclination of the horizontal branch pipe 23 is a slight inclination angle, for example, an inclination angle of 10 ° or less with respect to the horizontal direction.

The piping material 20 contains a resin composition (B) containing a polyvinyl chloride-based resin and heat-expandable graphite. That is, the piping material 20 is manufactured by molding the resin composition (B). Usually, the piping material 20 is manufactured by extrusion molding the resin composition (B).
The piping material 20 may have a single-layer structure in which the entire piping material 20 is made of the resin composition (B), or may be a multi-layer structure composed of a plurality of layers. In the case of a multi-layer structure, any layer may be formed from the resin composition (B). For example, when the piping material 20 has a three-layer structure including a surface layer, an intermediate layer, and an inner layer, the intermediate layer may be formed from the resin composition (B), and the surface layer, the intermediate layer, and the inner layer may be used. It may contain the endothermic agent.
The intermediate layer is black because it contains heat-expandable graphite. Therefore, it is preferable that the surface layer and the inner layer contain a colorant other than black so as to be distinguishable from the intermediate layer.
As the thickness of the intermediate layer, for example, in the case of a nominal diameter of 100 A (outer diameter 114 mm), it is preferably 1.8 mm or more and 7.6 mm or less, more preferably 2.0 mm or more and 6.0 mm or less, and 2.5 mm or more and 5 It is more preferably 0.0 mm or less. The thickness of the intermediate layer is preferably 85% or less, more preferably 60% or less, and even more preferably 50% or less of the thickness of the piping material. When the thickness of the intermediate layer is within the above range, both fire resistance and the strength of the piping material itself can be achieved.
The thickness of the surface layer and the inner layer is, for example, preferably 0.3 mm or more and 3.0 mm or less, and more preferably 0.6 mm or more and 1.5 mm or less in the case of a nominal diameter of 100 A (outer diameter 114 mm). When the thickness of the coating layer is 0.3 mm or more, sufficient mechanical strength as a pipe can be secured, and when it is 3.0 mm or less, deterioration of fire resistance can be suppressed.
Further, the piping material 20 preferably satisfies the performance described in JIS K6741.

[Resin composition (B)]
As the polyvinyl chloride-based resin contained in the resin composition (B), the same polyvinyl chloride-based resin as that contained in the resin composition (A) can be used.
Further, the resin composition (B) may contain various additives. As the additive, the same additive as the additive which may be contained in the resin composition (A) can be used.

The thermally expandable graphite contained in the resin composition (B) has a thermal expansion start temperature of 240 ° C. or higher, preferably 250 ° C. or higher, and more preferably 260 ° C. or higher. Here, the thermal expansion start temperature of the heat-expandable graphite is 1.1 times or more the volume before the start of temperature rise when the temperature of the heat-expandable graphite is raised from 150 ° C. to 5 ° C./min. It is the temperature when it expands to. The temperature interval for measuring the volume of the heat-expandable graphite is not particularly limited, and for example, the volume may be measured every time the temperature rises by 5 ° C.
The thermal expansion start temperature equal to or higher than the lower limit is sufficiently higher than the molding temperature at which the resin composition (B) is molded to produce the piping material 20. Therefore, when the thermal expansion start temperature of the thermally expandable graphite is at least the above lower limit value, it is possible to prevent the thermally expandable graphite from expanding when the resin composition (B) is formed.
On the other hand, the expansion start temperature of the heat-expandable graphite is preferably 400 ° C. or lower, more preferably 350 ° C. or lower. When the expansion start temperature of the heat-expandable graphite is not more than the upper limit, it is easy to industrially manufacture the heat-expandable graphite, and the pipe joint 10 is heated to be deformed or melted before the expansion of the heat-expandable graphite. Can be prevented.

Further, the heat-expandable graphite preferably has an expansion degree at 1000 ° C. of 180 cm ³ / g or more, and more preferably 185 cm ³ / g or more. Here, the degree of expansion of the heat-expandable graphite at 1000 ° C. is the volume (cm ³ ) per unit mass (g) after the heat-expandable graphite is held at 1000 ° C. for 10 seconds.
When the degree of expansion of the heat-expandable graphite is at least the above lower limit value, it expands sufficiently, so that the partition penetrating portion 2a can be more reliably closed in the event of a fire.
The degree of expansion of the heat-expandable graphite at 1000 ° C. is preferably 240 cm ³ / g or less from the viewpoint of facilitating the production of the heat-expandable graphite.

The heat-expandable graphite as described above is obtained by treating the graphite powder with an inorganic acid and an oxidizing agent. By this treatment, a crystalline compound in which an inorganic acid is inserted between layers of graphite can be obtained. A crystalline compound in which an inorganic acid is inserted between layers of graphite has thermal expansion properties.
Examples of the graphite include natural scaly graphite, pyrolytic graphite, quiche graphite and the like.
Examples of the inorganic acid include concentrated sulfuric acid, nitric acid, selenic acid and the like.
Examples of the oxidizing agent include concentrated nitrate, perchloric acid, perchlorate, permanganate, dichromate, hydrogen peroxide and the like.
After treating the graphite powder with the inorganic acid and the oxidizing agent, a neutralization treatment may be performed in order to reduce the acidity.

The heat-expandable graphite preferably has a pH adjusted to an acidic region, specifically, a pH of 1.0 or more and 7.0 or less, and a pH adjusted to 1.5 or more and 4.0 or less. preferable. When the pH of the heat-expandable graphite is adjusted to an acidic region, particularly pH 4.0 or less, the carbonization reaction of the polyvinyl chloride resin can be promoted in the event of a fire, and the carbonization structure is formed before the resin burns. Can be formed to reduce flammability. When the pH of the heat-expandable graphite is 1.5 or more, corrosion of the device with which the heat-expandable graphite comes into contact can be prevented.
The method for adjusting the pH of the heat-expandable graphite is not particularly limited. For example, in the production of heat-expandable graphite, a method of treating graphite powder with an inorganic acid and an oxidizing agent, and then repeating washing with water and drying to adjust the pH of the heat-expandable graphite can be mentioned.

The average particle size of the heat-expandable graphite is preferably 10 μm or more and 1000 μm or less, and more preferably 100 μm or more and 700 μm or less. Moreover, the average thickness is 100 μm or less.

The average aspect ratio of the heat-expandable graphite is 30 or less, preferably 28 or less, more preferably 26 or less, still more preferably 20 or less. Since the average aspect ratio of the heat-expandable graphite is 30 or less, the difference in the coefficient of linear expansion between the layer containing the heat-expandable graphite and the layer not containing the heat-expandable graphite can be reduced when the piping material has a multi-layer structure. Molding problems such as the intermediate layer and surface layer peeling off due to the effects of cleaning the inside of the piping material and the shrinkage difference due to the heat of high-temperature drainage, and the difference in shrinkage between the surface layer and intermediate layer after molding increases and the piping material warps. Can be suppressed.
The linear expansion coefficient of the rigid polyvinyl chloride resin constituting the piping material is 7.0 × 10 ^-5 / ° C as a value measured by the thermomechanical analysis method (TMA method) defined by JIS K 7197. , The piping material of the present embodiment is 4.5 × ^10-5 / ° C or higher and less than 7.0 × ^10-5 / ° C, and 5.0 × ^10-5 / ° C or higher and 7.0 × ^10-5 / ° C. It is preferably less than ° C, more preferably 5.5 × 10 ^-5 / ° C or higher and less than 6.8 × 10 ^-5 / ° C. The difference in the coefficient of linear expansion between the surface layer and the inner layer and the intermediate layer is 2.5 × ^10-5 / ° C or less, preferably 2.0 × ^10-5 / ° C or less, and 1.0 × ^10-5 / ° C. ℃ or less is more preferable.
Further, the fusion strength between the surface layer and the inner layer of the piping material and the intermediate layer is 0.8 MPa or more, preferably 1.0 MPa or more, more preferably 1.5 MPa or more, still more preferably 2.0 MPa or more.

The average aspect ratio is the ratio of the average diameter in the horizontal direction to the thickness in the vertical direction. Since the heat-expandable graphite used in the present invention has a substantially flat plate shape, it can be seen that the vertical direction coincides with the thickness direction and the horizontal direction coincides with the radial direction. The divided value is used as the aspect ratio.

Then, the aspect ratio is measured for a sufficiently large number, that is, 10 or more pieces of graphite, and the average value thereof is taken as the average aspect ratio. The average particle size of the heat-expandable graphite can also be obtained as the average value of the maximum horizontal dimensions.

The maximum horizontal dimension of the heat-expandable graphite and the thickness of the flaky graphite can be measured using, for example, a field emission scanning electron microscope (FE-SEM).

When the heat-expandable graphite whose pH is adjusted to 1.5 or more and 4.0 or less is used, it is preferable to use a heat stabilizer in combination. Examples of the heat stabilizer include lead-based stabilizers, tin-based stabilizers, Ca—Zn-based stabilizers, higher fatty acid metal salts, and the like. One type of heat stabilizer may be used alone, or two or more types may be used in combination.

Examples of lead-based stabilizers include lead white, basic lead sulfite, tribasic lead sulfate, dibasic lead phosphite, dibasic lead phthalate, tribasic lead maleate, and silica gel co-precipitated silicic acid. Examples thereof include lead, dibasic lead stearate, lead stearate, lead naphthenate and the like.
Examples of the tin-based stabilizer include mercaptides such as dibutyl tin mercapto, dioctyl tin mercapto, and dimethyl tin mercapto; malates such as dibutyl tin malate, dibutyl tin malate polymer, dioctyl tin malate, and dioctyl tin malate polymer; dibutyl. Examples thereof include carboxylates such as tin mercaptodibutyl tin laurate and dibutyltin laurate polymer.
The Ca—Zn-based stabilizer is a mixture of a fatty acid salt of calcium and a fatty acid salt of zinc. Examples of the fatty acid include behenic acid, stearic acid, lauric acid, oleic acid, palmitic acid, ricinoleic acid, benzoic acid and the like, and two or more of these may be used in combination.
Examples of the higher fatty acid metal salt include lithium stearate, magnesium stearate, calcium stearate, calcium laurate, calcium lysinorate, strontium stearate, barium stearate, barium laurate, barium lysinolate, cadmium stearate, and cadmium laurate. , Cadmium lysinolate, cadmium naphthenate, cadmium 2-ethylhexoate, zinc stearate, zinc laurate, zinc lysinolate, zinc 2-ethylhexoate, lead stearate, lead dibasic stearate, lead naphthenate, etc. Be done.

The content of the heat stabilizer is preferably 0.3 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the polyvinyl chloride resin. If the content of the heat stabilizer is at least the above lower limit, the thermal stability of the polyvinyl chloride resin at the time of molding can be improved, and if it is at least the above lower limit, the polyvinyl chloride resin at the time of combustion can be improved. Can be sufficiently carbonized, and sufficient fire resistance can be obtained.

Further, the resin composition (B) may contain the above-mentioned heat-dehydrated compound such as magnesium hydroxide and aluminum hydroxide in addition to the heat-expandable graphite, and may contain the heat-dehydrated compound. In addition, the fire resistance performance of the piping material 20 can be further improved. The content of the heat-dehydrated compound is preferably 0.1 parts by mass or more and 20.0 parts by mass or less, and 0.2 parts by mass or more and 5.0 parts by mass or less, based on 100 parts by mass of the polyvinyl chloride resin. It is more preferably 0.3 parts by mass or more and 3.0 parts by mass or less. When the content of the heat-dehydrated compound is not less than the lower limit value, the fire resistance can be further enhanced, and when the content is not more than the upper limit value, the mechanical strength of the piping material 20 can be sufficiently high. ..

Further, it is preferable that the resin composition (B) contains an inorganic filler in addition to the heat-expandable graphite.
Examples of the inorganic filler include inorganic compounds other than the heat absorbing agent, such as silica, diatomaceous earth, alumina, zinc oxide, zinc oxide, titanium oxide, calcium oxide, magnesium oxide, iron oxide, tin oxide, antimony oxide, ferrites, and calcium hydroxide. Basic magnesium carbonate, calcium carbonate, magnesium carbonate, zinc carbonate, barium carbonate, dawn night, hydrotalcite, calcium sulfate, barium sulfate, gypsum fiber, calcium silicate, talc, clay, mica, montmorillonite, bentonite, active white clay, Sepiolite, imogolite, sericite, glass fiber, glass beads, silica-based balun, aluminum nitride, boron nitride, silicon nitride, carbon black, graphite, carbon fiber, carbon balun, charcoal powder, various metal powders, potassium titanate, magnesium sulfate , Lead titanate zirconate, aluminum borate, molybdenum sulfide, silicon carbonate, stainless fiber, zinc phosphate, zinc borate, various magnetic powders, slag fibers, fly ash, dehydrated sludge and the like. Among the inorganic fillers, basic inorganic fillers such as calcium carbonate, calcium silicate, calcium hydroxide, calcium oxide, magnesium carbonate, magnesium oxide, barium carbonate, zinc oxide, zinc hydroxide and iron oxide are preferable.
The inorganic filler may be used alone or in combination of two or more.

The content of the inorganic filler is preferably 0.3 parts by mass or more and 50.0 parts by mass or less, and 1.0 part by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the polyvinyl chloride resin. Is more preferable. When the content of the inorganic filler is not less than the lower limit value, the fire resistance can be further enhanced, and when the content is not more than the upper limit value, the mechanical strength of the piping material 20 can be sufficiently high.
In particular, when a heat-expandable graphite whose pH is adjusted to 1.5 or more and 4.0 or less is used, the basic inorganic filler in the resin composition (B) is a polyvinyl chloride resin. It is preferably contained in a proportion of 0.3 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass. When the content ratio of the basic inorganic filler is equal to or higher than the lower limit, the thermal stability of molding the resin composition (B) to produce the piping material 20 becomes high, and the generation of carbides during molding can be prevented. If it is not more than the upper limit, the polyvinyl chloride resin at the time of a fire can be sufficiently carbonized, and the fire resistance can be further improved.

The content of the heat-expandable graphite in the resin composition (B) is preferably 10.0 parts by mass or more and 28.0 parts by mass or less with respect to 100 parts by mass of the polyvinyl chloride resin, and is preferably 15.0 parts by mass. It is more preferably 26.0 parts by mass or less, and further preferably 18.0 parts by mass or more and 24.0 parts by mass or less. When the content of the heat-expandable graphite in the resin composition (B) is at least the above lower limit value, the piping material 20 (particularly the first vertical pipe 21) can be sufficiently expanded in the event of a fire. The fire resistance in the compartment penetrating portion 2a can be further improved. On the other hand, when the content of the heat-expandable graphite in the resin composition (B) is equal to or less than the upper limit value, it is possible to prevent the piping material 20 from being broken due to excessive expansion and the fire resistance from being lowered. ..

[Manufacturing method of piping materials]
A piping material having a three-layer structure including a surface layer, an intermediate layer, and an inner layer is manufactured by using, for example, the manufacturing apparatus 60 shown in FIG.
The manufacturing apparatus 60 of this example includes a first extrusion molding machine 61, a second extrusion molding machine 62, a vacuum sizing device 63, a take-up machine 64, and a cutting machine 65.

The first extruder 61 includes a first extruder 68 for kneading, heating and melting the resin composition supplied from the hopper 66 and extruding it. The second extruder 62 includes a second extruder 69 for kneading, heating and melting the resin composition supplied from the hopper 67, and extruding the resin composition. A mold 70 is attached to the outlets of the first extruder 68 and the second extruder 69. The resin composition (B-2) constituting the surface layer and the inner layer of the piping material is supplied to the hopper 66 of the first extrusion molding machine 61. The resin composition (B-1) constituting the intermediate layer is supplied to the hopper 67 of the second extrusion molding machine 62. It is preferable that at least the resin composition (B-1) contains a polyvinyl chloride-based resin and heat-expandable graphite. That is, it is preferable to use the above-mentioned resin composition (B) as the resin composition (B-1).

As shown in FIG. 3, the die 70 is a three-layer extrusion die and includes a merging portion 71 and a molding portion 72. In the merging section 71, the molten resin (melted resin composition (B-2)) 73 introduced from the first extruder 68 and the molten resin (melted resin composition (B-2)) introduced from the second extruder 69. -1)) 74 merges, and these are stacked near the outlet of the merge portion 71. The laminated molten resins 73 and 74 are expanded in diameter in the laminated state in the molding portion 72 to become tubular. Then, the outer circumference and the inner circumference are regulated to a certain appropriate size by the diling 75 and the mandrel 76 provided at the tip of the molding portion 72, and the continuous piping material (hereinafter referred to as “continuous pipe”) 77 is used. Extruded.

At this time, it is preferable that the mold 70 is adjusted so that the molding temperature (resin temperature at the time of molding) is 175 ° C. or higher and lower than 240 ° C. The molding temperature is more preferably 180 ° C. or higher and 235 ° C. or lower, further preferably 185 ° C. or higher and 230 ° C. or lower, and particularly preferably 190 ° C. or higher and 225 ° C. or lower. By setting the molding temperature within the above range, the adhesion between the intermediate layer containing the heat-expandable graphite in a good kneaded state and the surface layer and the inner layer can be improved.
When the molding temperature is less than 170 ° C., the kneading state of the resin composition (B-1) containing the heat-expandable graphite is poor, the fluidity in the mold 70 is lowered, and molding becomes difficult. If the molding temperature exceeds 240 ° C., the thermally expandable graphite contained in the resin composition (B-1) expands in the mold 70.

Further, it is preferable that the molding temperature is adjusted so as to gradually increase from the first extrusion molding machine 61 and the second extrusion molding machine 62 to the mold 70. Specifically, the resin temperature at the connection portion between the first extruder 68 and the second extruder 69 and the mold 70 is set higher than the resin temperature of a general piping material, and is set to 150 ° C. or higher and the mold temperature or lower. It is preferably 170 ° C. or higher and more preferably the mold temperature or lower. The resin temperatures in the first extruder 68 and the second extruder 69 may be the same or different from each other. By raising the resin temperature in the second extrusion molding machine 62 for kneading the resin composition (B-1) containing the heat-expandable graphite higher than the resin temperature in the first extrusion molding machine 61, the fluidity of the resin is increased. It becomes easy to knead, and it becomes easy to supply the resin to the merging portion 71 in the mold 70.
If the resin temperature in the first extruder 68 and the resin temperature in the second extruder 69 are different, a large amount of heat stabilizer should be added to the resin having the higher temperature in order to improve the thermal stability. Is preferable.

Next, the continuous tube 77 extruded from the mold 70 is introduced into the vacuum sizing device 63. The vacuum sizing device 63 is for shaping and cooling the outer surface of the continuous pipe 77. As shown in FIG. 4, the vacuum sizing device 63 includes a main body 78 extending in the extrusion direction of the continuous pipe 77. An inlet 79 and an outlet 80 of the main body 78 are formed at one end and the other end of the main body 78 in the longitudinal direction. A vacuum chamber 82 to which a vacuum pump 81 is connected is provided on the inlet 79 side in the main body 78. A sizing sleeve 83 is arranged in the vacuum chamber 82. One end of the sizing sleeve 83 is connected to the inlet 79. Further, a cooling chamber 84 is provided between the vacuum chamber 82 and the outlet 80, and the sprinkler pipe 85 is arranged over the entire length of the vacuum chamber 82 and the cooling chamber 84.

When the continuous pipe 77 is supplied to the vacuum sizing device 63, the continuous pipe 77 expands due to the negative pressure of the vacuum pump 81, and the outer surface thereof is brought into close contact with the inner surface of the sizing sleeve 83 to form the continuous pipe 77. The surface layer, the inner layer, and the intermediate layer are in close contact with each other. Further, the sized continuous pipe 77 is cooled and cured by the cooling water sprinkled from the sprinkler pipe 85.
In addition, instead of this vacuum sizing device 63, a cooling water tank in which cooling water is stored may be used, and one provided with a sizing sleeve at the inlet of the cooling water tank can be used.

The pick-up machine 64 is for picking up the continuous pipe 77 at a constant speed. The take-up machine 64 includes a plurality of take-up rollers 86 pressed against the lower part and the upper part of the continuous pipe 77. A motor (not shown) is connected to at least one of the take-up rollers 86, and the take-up speed of the continuous pipe 77 is adjusted by controlling the rotation speed of the motor.

The cutting machine 65 is for cutting the continuous pipe 77 to a predetermined length. The cutting machine 65 includes a sensor 87 that detects the tip position of the continuous pipe 77, and a cutting blade 88 that is driven in conjunction with the sensor 87. When the tip of the continuous pipe 77 pushes the sensor 87, the cutting blade 88 is driven to cut the continuous pipe 77, and a piping material having a predetermined length is obtained.

(Installation example of piping structure and action effect)
In the piping structure 1 of the present embodiment, one receiving port 11a of the main section 11 constituting the pipe joint 10 is arranged inside the section penetrating portion 2a, and the first standing pipe 21a is arranged in the receiving port 11a. The upper end of is connected.
Further, in the piping structure 1 of the present embodiment, the other receiving port 11b of the main section 11 is arranged outside the section penetrating portion 2a and above the floor slab 2, and the receiving port 11b is used for a second vertical pipe. The lower end of the pipe 22 is connected. Further, a receiving port 12a of the lateral branch pipe connecting portion 12 is arranged outside the partition penetrating portion 2a and above the floor slab 2, and one end of the lateral branch pipe connecting portion 23 is connected to the receiving port 12a.
The connection method between the sockets 11a, 11b, 12a and the pipes 21, 22, 23 is not particularly limited, and a known method can be appropriately applied. The gap between the inner surface of each socket may be stopped, or the outer surface of each pipe may be coated with an adhesive so that the inner surface of each receptacle and the outer surface of each pipe are connected so as to be water-stopped. When joining using an adhesive, as the adhesive, a colored adhesive to which a colorant is added or an adhesive to which a light emitting agent that emits fluorescence / phosphorescence by ultraviolet rays is added can be used. However, the receiving port 11a and the pipe 21 located inside the partition penetrating portion 2a need to be connected to each other with an adhesive so as not to fall off from the receiving port 11a even when the pipe 21 is heated and thermally expanded.
The outer surface of the end portion of each pipe 21, 22, 23 inserted into each of the receiving ports 11a, 11b, 12a of the pipe joint 10 is tapered over the entire circumference. The tapered surface referred to here may be a shape in which the end portion 20a of the piping material 20 along the pipe axis is cut off in a straight line, for example, as shown in FIG. 5A. Further, the end portion 20a of the piping material 20 may have a shape cut out by an arc as shown in FIG. 5B, for example. 5 (a) and 5 (b) are partial cross-sectional views at the end 20a of the piping material 20 having a three-layer structure of the inner layer 26, the intermediate layer 27 and the surface layer 28.
When the pipes 21 and 22 and 23 have a three-layer structure of an inner layer, an intermediate layer and a surface layer and the intermediate layer is composed of the resin composition (B), when the pipes 21 and 22 and 23 are inserted into the pipe joint 10, they are intermediate. The surface layer may be cut until the layer is exposed, or the intermediate layer may be cut to the extent that the intermediate layer is not exposed. If the intermediate layer is exposed, if the pipe joint 10 is transparent, the intermediate layer of the exposed piping material 20 end face is black, so the position of the end face can be visually recognized from the outside, and whether or not it is inserted all the way into the socket. Can be seen. In particular, when the joint is transparent, the packing provided in the receiving port can be visually recognized from the outside, so that it can be determined whether the end portion of the piping material 20 is inserted by a predetermined length from the packing. If the intermediate layer is not exposed, the adhesive component does not invade the intermediate layer or the interface between the intermediate layer and the surface layer, and the adhesive component prevents the interface between the surface layer and the intermediate layer from peeling or cracking, or is acidic. It is possible to prevent the adhesive component from deteriorating due to the heat-expandable graphite.

As described above, the piping material 20 used in the piping structure 1 of the present embodiment contains thermally expandable graphite that expands when a fire occurs and is heated. Therefore, for example, as shown in FIG. 6, when a fire breaks out on the floor below the floor slab 2, the heat of the fire causes the portion of the first vertical pipe 21 to expand in the section penetrating portion 2a. The section penetrating portion 2a can be closed. As a result, flame, heat and smoke can be prevented from rising to the floor above the floor slab 2 through the compartment penetration portion 2a, so that fire resistance can be exhibited.
The thermally expandable graphite used in the present embodiment has a thermal expansion start temperature of 240 ° C. or higher, which is higher than the molding temperature (140 ° C. or higher and lower than 240 ° C.) at the time of producing the piping material. Therefore, it is prevented that the heat-expandable graphite expands when the piping material 20 is manufactured. Therefore, the piping material 20 in this embodiment is easy to manufacture.
In particular, when manufacturing a piping material having a three-layer structure consisting of a surface layer, an intermediate layer containing thermally expandable graphite, and an inner layer, the molding temperature (resin temperature at the time of molding) is preferably 175 ° C. or higher and lower than 240 ° C. , 180 ° C. or higher and 235 ° C. or lower is more preferable, 185 ° C. or higher and 230 ° C. or lower is further preferable, and 190 ° C. or higher and 225 ° C. or lower is particularly preferable. By setting the molding temperature within the above range, the adhesion between the intermediate layer containing the heat-expandable graphite in a good kneaded state and the surface layer and the inner layer can be improved.
Further, by increasing the molding temperature, the fluidity of the resin can be increased, and even a resin containing heat-expandable graphite can be easily kneaded, merged, and extruded, and the moldability can be improved.

When the thermal expansion start temperature of the heat-expandable graphite contained in the piping material 20 is high, when a fire occurs, the heat of the fire is generated before the piping material 20 thermally expands and closes the partition penetrating portion 2a. There is a risk that the pipe joint 10 will be deformed or melted and the fire resistance will be reduced. However, since the pipe joint 10 constituting the pipe structure 1 of the present embodiment contains an endothermic agent, even if a fire occurs on the lower floor of the floor slab 2 and heat is transferred to the pipe joint 10. , The endothermic agent can absorb heat. Therefore, it is possible to delay the melting and deformation of the pipe joint 10. As a result, the first vertical pipe 21 can be reliably thermally expanded to close the partition penetrating portion 2a before the pipe joint 10 is melted and deformed, and the fire resistance can be sufficiently exhibited.
Therefore, according to the piping structure 1 of the present embodiment, although the thermal expansion start temperature of the piping material 20 is high and it is easy to manufacture the piping material 20, the piping material 20 thermally expands in the event of a fire. It is possible to suppress the deformation of the pipe joint 10 before, and it is possible to reliably close the section penetrating portion 2a. Therefore, the piping structure 1 of the present embodiment is excellent in the fire resistance of the section penetrating portion 2a.

In a building, a flooring material 4 for a living area is usually separately installed above a floor slab 2 that divides adjacent upper and lower floors. A space S is formed between the floor slab 2 and the floor material 4, and the horizontal branch pipe 23 is arranged in the space S. Therefore, the installation space of the horizontal branch pipe 23 is limited, but usually, in order to improve the drainage property, the horizontal branch pipe 23 is gradually increased as it is separated from the receiving port 12a of the horizontal branch pipe connecting portion 12. Is inclined to. Due to such circumstances, in the pipe joint 10, the lateral branch pipe connecting portion 12 is made as close as possible to the floor slab 2, the connection position of the lateral branch pipe 23 is lowered as much as possible, and the lateral branch in the space S is formed. It is required to increase the degree of freedom in the arrangement of the pipe 23. In particular, when the building is an apartment house and there are many rooms on the same floor, the horizontal branch pipe 23 becomes long. In that case, in the horizontal branch pipe 23, the horizontal branch pipe connection portion 12 side and The position of the opposite end will be high. Therefore, it is required to make effective use of the space between the floor slab 2 and the floor material 4. For this reason, in the pipe joint 10, the main pipe portion 11 is inserted as deeply as possible into the section penetrating portion 2a, the lateral branch pipe connecting portion 12 is brought close to the floor slab 2, and the horizontal branch pipe is used at a position as low as possible. It is preferable to connect the pipe 23. Further, it is preferable that at least the upper end of the receiving port 11a does not exceed the upper surface of the floor slab 2, that is, the upper end of the vertical pipe 21 does not exceed the upper surface of the floor slab 2.
When the main pipe portion 11 is deeply inserted into the compartment penetrating portion 2a, the lower receiving port 11a of the pipe joint 10 approaches the lower floor. In the present embodiment, the main portion 11 is inserted into the compartment penetrating portion 2a until the lower surface of the receiving port 11a is flush with the lower surface of the floor slab 2.
When the lower receiving port 11a of the pipe joint 10 is close to the lower floor, the pipe joint 10 is quickly exposed to flame and heat when a fire breaks out on the lower floor. Further, the length in the section penetrating portion 2a of the vertical pipe 21 containing the heat-expandable graphite is short, and the closing length by the expanded pipe 21 is short. However, even in such a case, in the present embodiment using the pipe joint 10 containing the endothermic agent, the temperature rise of the pipe joint 10 can be delayed, so that the deformation of the pipe joint 10 can be suppressed. Further, in the present embodiment, since the blending amount of the heat-expandable graphite is sufficiently large, the partition penetrating portion 2a can be sufficiently closed even if the closing length of the partition penetrating portion 2a is short.
Therefore, according to the present embodiment, it is possible to secure the fire resistance in the section penetrating portion 2a while increasing the degree of freedom in arranging the horizontal branch pipe 23 in the space S between the floor slab 2 and the floor material 4.

(Other embodiments)
The present invention is not limited to the above embodiment.
For example, in the present invention, it is not necessary to connect the pipe joint and the upper end portion of the first vertical pipe in a state where the lower surface of the lower receiving port of the pipe joint is flush with the lower surface of the floor slab. .. That is, the lower receiving port of the pipe joint and the upper end portion of the first vertical pipe may be connected at any part in the section penetrating portion.
In the present invention, the pipe joint is not limited to the three-way pipe joint having the shape described in the above embodiment, and may be a T-shaped pipe joint in which the lateral branch pipe connection portion is provided perpendicularly to the main portion of the pipe joint. .. Further, the pipe joint may connect two vertical pipes and two or more horizontal branch pipes, or connect one vertical pipe and two or more horizontal branch pipes. But it may be.
In the piping material, at least the vertical pipe may be composed of the resin composition (B), and the horizontal branch pipe contains a resin composition other than the resin composition (B), that is, heat-expandable graphite. It may be composed of no resin composition.
Further, in the present invention, the piping material may be provided with a receiving port at one end. In this case, the pipe joint is configured to have a spigot inserted into the receiving port of the pipe material, and the pipe fitting is formed by inserting the spout of the pipe joint into the receiving port of the pipe material and connecting the pipe joint.
Further, the piping structure of the present invention may be passed through a section penetrating portion formed on a wall. When the pipe structure is to be passed through a partition penetration portion formed in a wall, the pipe joint may be provided with two receiving ports, or may be provided with three or more receiving ports. It may be a thing.
Further, the piping structure of the present invention can also be used for a water supply channel.

Further, in the above embodiment, fire resistance is imparted by adding a heat-dehydrated compound to the resin composition (A), but the present invention is not limited to this, and fire resistance is imparted by adding non-thermally expanded graphite. You may. As the non-thermally expanded graphite, those described in Japanese Patent No. 4829847 can be used, and translucent or transparent by using a non-thermally expanded graphite having a particle size of 10 μm or more and 1000 μm or less, preferably 10 μm or more and 100 μm or less. Can be a good joint.

Further, the piping structure of the present invention may be in a state in which the piping material and the pipe joint are joined with an adhesive in advance at a factory or the like.
In this case, the piping structure 1 includes, for example, an upper pipe joint 10a, a lower pipe joint 10b, and a piping material 20 as shown in FIG. 7.
The upper pipe joint 10a can connect a receiving port 13a to which the piping material 20 can be connected, a receiving port 11b to which a second standing pipe 122 extending from the upper floor can be connected, and a horizontal branch pipe 123 extending from the upper floor. It is provided with a receiving port 12a.
The lower pipe joint 10b includes a receiving port 13b to which the piping material 20 can be connected, and a receiving port 11a to which a first vertical pipe 121 extending from the lower floor can be connected.
The upper end of the piping material 20 is connected to the receiving port 13a of the upper pipe joint 10a. The lower end of the piping material 20 is connected to the receiving port 13b of the lower pipe joint 10b.
The upper pipe joint 10a and the lower pipe joint 10b are made of the resin composition (A). The piping material 20 is made of the resin composition (B). The first vertical pipe 121, the second vertical pipe 122, and the horizontal branch pipe 123 may be composed of the resin composition (A) or the resin composition (B). It may be composed of a material other than the resin composition (A) and the resin composition (B).
The piping structure 1 shown in FIG. 7 is installed in the building so that the piping material 20 is arranged in the section penetrating portion 2a of the floor slab 2. Further, the mortar 3 is filled between the pipe structure 1 and the inner side surface of the section penetrating portion 2a to fill the gap between the inner side surface of the section penetrating portion 2a and the piping material 20 and the piping structure. The body 1 is fixed.

In the piping structure 1 shown in FIG. 7, the receiving port 13a of the upper pipe joint 10a and the piping material 20 are connected in the section penetrating portion 2a of the floor slab 2, but the receiving port 13b of the lower pipe joint 10b and the pipe are connected. The material 20 may be connected to the partition penetration portion 2a of the floor slab 2. Further, the receiving port 13a and the piping material 20 of the upper pipe joint 10a and the receiving port 13b and the piping material 20 of the lower pipe joint 10b may be connected in the section penetrating portion 2a of the floor slab 2, respectively.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples.

(Example 1)
100 parts by mass of polyvinyl chloride resin (manufactured by Taiyo PVC Co., Ltd., TH700) and magnesium hydroxide as a heat absorbing agent (manufactured by Kyowa Chemical Industry Co., Ltd., Kisma 5A, volume average particle size: 0.9 μm, BET specific surface area: 4 .8m ² / g) 1 part by mass, tin stabilizer (manufactured by Nitto Kasei Co., Ltd., AT-6300) 2 parts by mass, polyethylene-based lubricant (manufactured by Mitsui Chemicals Co., Ltd., High Wax 4202E) 0.5 parts by mass. After blending, a resin composition (A-1) was obtained by stirring and mixing using a Henschel mixer (manufactured by Kawada Kogyo Co., Ltd.) having an internal volume of 200 liters.
The resin composition (A-1) was injection-molded at a molding temperature of 190 ° C. using an injection molding machine to produce a pipe joint having the same shape as that of the above embodiment.

The piping material was composed of a surface layer, an intermediate layer and an inner layer.
The resin composition constituting the intermediate layer was obtained as follows.
100 parts by mass of polyvinyl chloride resin (manufactured by Taiyo PVC Co., Ltd., TH1000) and heat-expandable graphite (manufactured by Air Water Co., Ltd., MZ-260, expansion start temperature 260 ° C. or higher, average aspect ratio 25.3) 18 By mass, 2 parts by mass of lead-based stabilizer (Sakai Chemical Co., Ltd., SL-1000), 0.5 part by mass of polyethylene-based lubricant (Mitsui Chemical Co., Ltd., High Wax 4202E), aluminum hydroxide (Showa Denko Co., Ltd.) After blending with 3 parts by mass of H-42S) manufactured by the company, the resin composition (B-1) was obtained by stirring and mixing using a Henschel mixer (manufactured by Kawada Kogyo Co., Ltd.) having an internal volume of 200 liters.
The resin composition constituting the surface layer and the inner layer was obtained as follows.
100 parts by mass of polyvinyl chloride resin (TH1000 manufactured by Taiyo PVC Co., Ltd.), 2 parts by mass of lead-based stabilizer (SL-1000 manufactured by Sakai Chemical Co., Ltd.), polyethylene-based lubricant (High Wax 4202E manufactured by Mitsui Chemicals Co., Ltd.) After blending 0.5 parts by mass and 3 parts by mass of calcium carbonate (manufactured by Shiraishi Calcium Co., Ltd., Whiten SB), the resin composition (manufactured by Kawada Kogyo Co., Ltd.) with an internal volume of 200 liters is stirred and mixed. B-2) was obtained.
Using the manufacturing apparatus shown in FIG. 2, the resin composition (B-2) is supplied to the hopper 66 of the first extrusion molding machine 61, and the resin composition (B-) is supplied to the hopper 67 of the second extrusion molding machine 62. 1) was supplied. The resin temperature in the first extruder 68 and the second extruder 69 was set to 180 ° C., and each resin was supplied from the first extruder 68 and the second extruder 69 to the mold 70. The molding temperature of the mold 70 is set to 190 ° C., and the mold is extruded into a tubular shape. The outer diameter is 114 mm, and the resin composition (B-2) is composed of a surface layer and an inner layer having a thickness of 0.8 mm, respectively, and a resin composition. A piping material composed of an object (B-1) and having an intermediate layer having a thickness of 4 mm formed between the surface layer and the inner layer was produced. This piping material was cut to produce three pipes 21, 22, and 23.

[Coefficient of linear expansion]
The measurement was performed in accordance with the thermomechanical analysis method (TMA method) specified in JIS K 7197. The results are shown in Table 1.

[Fusion strength]
The universal testing machine 50 shown in FIG. 8 was prepared. The universal testing machine 50 includes a punching jig 51 and two compression plates (not shown). The punching jig 51 includes a pedestal portion 51a and a pushing portion 51b arranged above the pedestal portion 51a. The punching jig 51 is sandwiched between two compression plates (not shown).
Next, a test piece 25 was obtained by cutting the piping material into a tubular shape having a width of 20 mm in the pipe axis direction. The test piece 25 has an inner layer 26, an intermediate layer 27, and a surface layer (not shown).
Under the conditions of a temperature of 23 ° C. ± 2 ° C. and a humidity of normal humidity (45 to 85%), the test piece 25 is set between the pedestal portion 51a and the pushing portion 51b of the universal testing machine 50, and two compression plates are set. The test piece 25 is compressed at a speed of 10 mm / min ± 2 mm / min per minute in the direction of the tube axis, and the maximum load when the fused surface between the inner layer 26 and the intermediate layer 27 is peeled off is obtained by the following formula ( The fusional strength was calculated in 1) and (2). The results are shown in Table 1.
F = W / S ... (1)
S = 3.14 × d × L ・ ・ ・ (2)
[In the formulas (1) and (2), F is the fusion strength (MPa), W is the maximum load (N), S is the fusion area (cm ² ), and d is the average of the inner layers 26. Outer diameter (cm), L is the length of the test piece in the direction of the tube axis (cm)]

[Evaluation of moldability]
Observing the appearance of the obtained piping material, there is either warpage or peeling between the intermediate layer and the surface layer, and the one with a remarkable degree is marked with "x", and either the warp or the peeling between the intermediate layer and the surface layer is If there is, the one that is acceptable to that extent is given as "△", and the one that does not have any of them is given as "○". The results are shown in Table 1.

[Fire resistance evaluation]
The refractory test furnace 100 shown in FIG. 9 was prepared. The refractory test furnace 100 includes a heating chamber 110 that is sealed except above, a test floor slab 120 installed on the heating chamber 110, and a burner 130 provided in the heating chamber 110 to generate a flame. A thermocouple 140 for measuring the temperature in the heating chamber 110 is provided. As the floor slab 120, a PC (precast concrete) panel having a thickness of 100 mm in which a partition penetration portion 120a having a diameter of 260 mm was formed was used. The thermocouple 140 was arranged so that the temperature near the lower end of the piping material 20 (first vertical pipe 21) in the heating chamber 110 could be measured. Further, a mortar 3 was filled between the pipe joint 10 and the inner side surface of the compartment penetrating portion 120a to seal the compartment penetrating portion 120a.
In this fire resistance test furnace 100, the pipe joint 10 and the pipe material 20 produced as described above were used, and the pipe structure 1 was installed in the same arrangement as in the above embodiment.
Then, a fire resistance test (according to ISO834-1, the evaluation method of the fire resistance performance test of the revised Building Standards Act enforced on June 1, 2000) was conducted. In this fire resistance test, the time (smoke generation time) from the start of heating until smoke is emitted from the gap between the pipe joint 10 and the partition penetrating portion 120a was measured. According to the criteria for the 8 divisions of the Fire Service Act, if the smoke emission time is 120 minutes or more, it is considered to be fire resistant, and if it is less than 120 minutes, it is considered to be non-fire resistant.
When the fire resistance test was performed on the piping structure of Example 1, smoke did not flow out from between the pipe joint 10 and the compartment penetration portion 120a even after 120 minutes from the start of heating, and the pipe structure had fire resistance. Was.

(Example 2)
The amount of the heat-expandable graphite to be blended in the resin composition (B-1) constituting the intermediate layer of the piping material is 16 parts by mass, and the stabilizer to be blended in the resin composition (B-2) constituting the surface layer and the inner layer. A tin-based stabilizer (manufactured by Nitto Kasei Co., Ltd., AT-6300) was prepared in an amount of 2 parts by mass, and a piping material was produced in the same manner as in Example 1 except that 3 parts by mass of aluminum hydroxide was blended as a heat absorbing agent. For the piping material of Example 2, the coefficient of linear expansion was measured by the above method in the same manner as in Example 1, the fusional strength was calculated, and the moldability evaluation and the fire resistance evaluation were carried out. The piping material of Example 2 had excellent moldability and fire resistance. The results are shown in Table 1.

(Example 3)
Example 1 except that the amount of the heat-expandable graphite blended in the resin composition (B-1) constituting the intermediate layer of the piping material is 20 parts by mass and the thickness of the surface layer and the inner layer is 1.3 mm, respectively. The piping material was produced in the same manner as above. For the piping material of Example 3, the coefficient of linear expansion was measured by the above method in the same manner as in Example 1, the fusional strength was calculated, and the moldability evaluation and the fire resistance evaluation were carried out. The piping material of Example 3 had excellent moldability and fire resistance. The results are shown in Table 1.

(Example 4)
As the heat-expandable graphite to be blended in the resin composition (B-1) constituting the intermediate layer of the piping material, the heat-expandable graphite A (expansion start temperature 280) prepared by the method described in Example 2 of Patent No. 5130295 A piping material was produced in the same manner as in Example 1 except that 18 parts by mass was used at ° C. and an average aspect ratio of 17.9). For the piping material of Example 4, the coefficient of linear expansion was measured by the above method in the same manner as in Example 1, the fusional strength was calculated, and the moldability evaluation and the fire resistance evaluation were carried out. The piping material of Example 4 had excellent moldability and fire resistance. The results are shown in Table 2.

(Example 5)
As the heat-expandable graphite to be blended in the resin composition (B-1) constituting the intermediate layer of the piping material, the heat-expandable graphite B (expansion start temperature 290) prepared by the method described in Example 2 of Patent No. 5084930. A piping material was produced in the same manner as in Example 1 except that 18 parts by mass was used at ° C. and an average aspect ratio of 14.1). For the piping material of Example 5, the coefficient of linear expansion was measured by the above method in the same manner as in Example 1, the fusional strength was calculated, and the moldability evaluation and the fire resistance evaluation were carried out. The piping material of Example 5 had excellent moldability and fire resistance. The results are shown in Table 2.

(Example 6)
The amount of heat-expandable graphite to be blended in the resin composition (B-1) constituting the intermediate layer of the piping material is 20 parts by mass, the amount of lead-based stabilizer is 4 parts by mass, and the thickness of the surface layer and the inner layer is set. The piping material was produced in the same manner as in Example 1 except that the resin temperature in the second extruder when producing the piping material was set to 1.3 mm and the molding temperature in the mold was set to 225 ° C. .. For the piping material of Example 6, the coefficient of linear expansion was measured by the above method in the same manner as in Example 1, the fusional strength was calculated, and the moldability evaluation and the fire resistance evaluation were carried out. The piping material of Example 6 had excellent moldability and fire resistance. The results are shown in Table 2.

(Example 7)
A pipe joint was produced in the same manner as in Example 1 except that the amount of the endothermic agent blended in the resin composition (A-1) constituting the pipe joint was 0.5 parts by mass. Further, the piping material was produced in the same manner as in Example 1 except that the amount of aluminum hydroxide blended in the resin composition (B-1) constituting the intermediate layer of the piping material was 1 part by mass. Fire resistance evaluation was carried out in the same manner as in Example 1 except that the pipe joint and the pipe material were used. The pipe joint of Example 7 was not easily deformed and had fire resistance. The results are shown in Table 3.
Further, for the piping material of Example 7, the coefficient of linear expansion was measured by the above method in the same manner as in Example 1, the fusional strength was calculated, and the formability was evaluated. The piping material of Example 7 was excellent in moldability. The results are shown in Table 3.

(Example 8)
Magnesium hydroxide (manufactured by Kyowa Chemical Industry Co., Ltd., Kisma 8, volume average particle size: 1.5 μm, BET specific surface area: 3.1 m ² ) as a heat absorbing agent to be blended in the resin composition (A-1) constituting the pipe joint. A pipe joint was produced in the same manner as in Example 1 except that 2 parts by mass of / g) was used. Further, the piping material was produced in the same manner as in Example 1 except that the amount of aluminum hydroxide blended in the resin composition (B-1) constituting the intermediate layer of the piping material was 1 part by mass. The fire resistance evaluation was carried out in the same manner as in Example 1 except that the pipe joint and the pipe material were used. The pipe joint of Example 8 was not easily deformed and had fire resistance. The results are shown in Table 3.
Further, for the piping material of Example 8, the coefficient of linear expansion was measured in the same manner as in Example 1 by the above method, the fusional strength was calculated, and the formability was evaluated. The piping material of Example 8 was excellent in moldability. The results are shown in Table 3.

(Example 9)
Kaolinite (manufactured by BASF, ASP-900, volume average particle size: 1.5 μm, BET specific surface area: 12.2 m ² / g) as a heat absorbing agent to be blended in the resin composition (A-1) constituting the pipe joint. A pipe joint was produced in the same manner as in Example 1 except that 3 parts by mass was used. Further, the piping material was produced in the same manner as in Example 1 except that the amount of aluminum hydroxide blended in the resin composition (B-1) constituting the intermediate layer of the piping material was 1 part by mass. The fire resistance evaluation was carried out in the same manner as in Example 1 except that the pipe joint and the pipe material were used. The pipe joint of Example 9 was not easily deformed and had fire resistance. The results are shown in Table 3.
Further, for the piping material of Example 9, the coefficient of linear expansion was measured by the above method in the same manner as in Example 1, the fusional strength was calculated, and the formability was evaluated. The piping material of Example 9 was excellent in moldability. The results are shown in Table 3.

(Example 10)
As the heat-expandable graphite to be blended in the resin composition (B-1) constituting the intermediate layer of the piping material, the heat-expandable graphite C (expansion start temperature 275) prepared by the method described in Example 5 of Patent No. 5130295 A piping material was produced in the same manner as in Example 1 except that ° C. and an average aspect ratio of 33.1) were used. With respect to the piping material of Example 10, the linear expansion coefficient was measured by the above method in the same manner as in Example 1, the fusional strength was calculated, and the moldability evaluation and the fire resistance evaluation were carried out. The piping material of Example 10 had fire resistance. The results are shown in Table 4.
However, Example 10 is a reference example.

(Example 11)
The piping material was produced in the same manner as in Example 1 except that the resin temperature in the second extruder when producing the piping material was 145 ° C. and the molding temperature in the mold was 170 ° C. With respect to the piping material of Example 11, the linear expansion coefficient was measured by the above method in the same manner as in Example 1, the fusional strength was calculated, and the moldability evaluation and the fire resistance evaluation were carried out. The piping material of Example 11 had fire resistance. The results are shown in Table 4.

(Comparative Example 1)
A pipe joint was produced in the same manner as in Example 1 except that magnesium hydroxide was not added to the resin composition (A). When the fire resistance evaluation was carried out in the same manner as in Example 1 except that this pipe joint was used, the pipe joint was deformed within 120 minutes from the start of heating, and a gap was formed between the pipe joint 10 and the partition penetrating portion 120a. Was formed, and smoke flowed out from the gap. That is, the piping structure of Comparative Example 1 could not sufficiently exhibit fire resistance.
Further, for the piping material of Comparative Example 1, the coefficient of linear expansion was measured in the same manner as in Example 1 by the above method, the fusional strength was calculated, and the formability was evaluated. The piping material of Comparative Example 1 was excellent in moldability. The results are shown in Table 5.

(Comparative Example 2)
As the heat-expandable graphite to be blended in the resin composition (B-1) constituting the intermediate layer of the piping material, the heat-expandable graphite D (manufactured by Tosoichi Co., Ltd., GREP-EG, expansion start temperature 220 ° C., aspect ratio) A piping material was produced in the same manner as in Example 1 except that 18.2) was used. For the piping material of Comparative Example 2, the coefficient of linear expansion was measured in the same manner as in Example 1 by the above method, the fusional strength was calculated, and the moldability evaluation and the fire resistance evaluation were carried out. The piping material of Comparative Example 2 could not sufficiently exhibit fire resistance and moldability. The results are shown in Table 5.

1 Piping structure 2 Floor slab 2a Section penetration 3 Mortal 4 Floor material 10 Pipe fitting 10a Upper pipe fitting 10b Lower pipe fitting 11 Main pipe 11a, 11b Receptacle 12 Horizontal branch pipe connection 12a Receptacle 13a, 13b Receptacle 20 Piping material 21 First vertical pipe (piping material)
22 Second vertical pipe (piping material)
23 Horizontal branch pipe (piping material)

Claims (7)

A drainage piping material having a multi-layer structure having at least a surface layer, an intermediate layer, and an inner layer.
The surface layer and the inner layer contain a polyvinyl chloride resin, and the surface layer and the inner layer contain a polyvinyl chloride resin.
The intermediate layer contains a polyvinyl chloride resin and a heat-expandable graphite.
The thermal expansion graphite has a thermal expansion start temperature of 240 ° C. or higher.
The content of the heat-expandable graphite in the intermediate layer is 1 5. by mass with respect to 100 parts by mass of the polyvinyl chloride resin in the intermediate layer. More than 0 parts by mass and less than 28.0 parts by mass,
A drainage piping material having an average aspect ratio of the heat-expandable graphite of less than 20. A drainage piping material having a multi-layer structure having at least a surface layer, an intermediate layer, and an inner layer.
The surface layer and the inner layer contain a rigid polyvinyl chloride resin, and the surface layer and the inner layer contain a rigid polyvinyl chloride resin.
The intermediate layer contains a hard polyvinyl chloride resin, thermally expandable graphite, and aluminum hydroxide.
The thermal expansion graphite has a thermal expansion start temperature of 240 ° C. or higher.
The content of the heat-expandable graphite in the intermediate layer is 1 5. by mass of the hard polyvinyl chloride resin in the intermediate layer. It is 0 parts by mass or more and 28.0 parts by mass or less.
The average aspect ratio of the heat-expandable graphite is less than 20 .
The coefficient of linear expansion specified by JIS K 7197 is 5 . Drainage piping material with a temperature of 5 × ^10-5 / ° C or higher and lower than 7.0 × ^10-5 / ° C (excluding those in which the rigid polyvinyl chloride resin contains a plasticizer). The drainage piping material according to claim 2, wherein the fusion strength between the inner layer and the intermediate layer is 0.8 MPa or more. A drainage piping material having a multi-layer structure having at least a surface layer, an intermediate layer, and an inner layer.
The surface layer and the inner layer contain a polyvinyl chloride resin, and the surface layer and the inner layer contain a polyvinyl chloride resin.
The intermediate layer contains a polyvinyl chloride resin, thermally expandable graphite, and aluminum hydroxide.
The thermal expansion graphite has a thermal expansion start temperature of 260 ° C. or higher.
The content of the heat-expandable graphite in the intermediate layer is 1 5. by mass of the hard polyvinyl chloride resin in the intermediate layer. It is 0 parts by mass or more and 28.0 parts by mass or less.
The average aspect ratio of the heat-expandable graphite is less than 20 .
A drainage piping material in which the content of aluminum hydroxide in the intermediate layer is 0.2 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the polyvinyl chloride resin in the intermediate layer. It is a piping structure in which the upper pipe joint and the lower pipe joint and the drainage piping material are previously joined.
The drainage piping material is a drainage piping material having a multi-layer structure having at least a surface layer, an intermediate layer, and an inner layer.
The surface layer and the inner layer contain a polyvinyl chloride resin, and the surface layer and the inner layer contain a polyvinyl chloride resin.
The intermediate layer contains a polyvinyl chloride resin and a heat-expandable graphite.
The thermally expandable graphite has a thermal expansion start temperature of 240 ° C. or higher and an average aspect ratio of less than 20 .
The content of the heat-expandable graphite in the intermediate layer is 1 5. by mass with respect to 100 parts by mass of the polyvinyl chloride resin in the intermediate layer. It is 0 parts by mass or more and 28.0 parts by mass or less.
The upper pipe joint has a receiving port to which the upper end of the drainage piping material can be connected.
The lower pipe joint has a receiving port to which the lower end of the drainage piping material can be connected.
When the piping structure is installed, at least the drainage piping material is located in the partition penetration portion of the floor slab, and the connection portion between the drainage piping material and the receiving port of the upper pipe joint, and the drainage. Both or one of the connection portions between the piping material and the receiving port of the lower pipe joint is located in the partition penetration portion of the floor slab.
The drainage piping material projects downward from the floor slab and
The connection portion between the drainage piping material and the receiving port of the upper pipe joint is located in the partition penetration portion of the floor slab.
The connection portion between the drainage pipe material and the receiving port of the lower pipe joint is a pipe structure located outside the partition penetration portion of the floor slab (however, a swivel blade is installed inside the drainage pipe material. Except for the ones). It is a method for manufacturing a drainage piping material having a multi-layer structure having at least a surface layer, an intermediate layer, and an inner layer.
The surface layer and the inner layer contain a hard polyvinyl chloride resin and a colorant other than black.
The intermediate layer contains a rigid polyvinyl chloride resin and a heat-expandable graphite.
The content of the heat-expandable graphite in the intermediate layer is 1 5. by mass of the hard polyvinyl chloride resin in the intermediate layer. It is 0 parts by mass or more and 28.0 parts by mass or less.
The thermally expandable graphite has a thermal expansion start temperature of 240 ° C. or higher and an average aspect ratio of less than 20 .
The surface layer, the intermediate layer, and the inner layer are laminated and extruded using a three-layer extrusion die having a temperature of 190 ° C. or higher and lower than 240 ° C., and then introduced into a sizing sleeve to shape the outer surface.
Method for manufacturing drainage piping material (excluding those in which the rigid polyvinyl chloride resin contains a plasticizer). It is a method for manufacturing a drainage piping material having a multi-layer structure having at least a surface layer, an intermediate layer, and an inner layer.
The surface layer and the inner layer contain a polyvinyl chloride resin, a heat stabilizer, and a colorant other than black.
The intermediate layer contains a polyvinyl chloride resin, a heat-expandable graphite, and a heat stabilizer.
The content of the heat-expandable graphite in the intermediate layer is 10.0 parts by mass or more and 28.0 parts by mass or less with respect to 100 parts by mass of the polyvinyl chloride resin in the intermediate layer.
The thermal expansion graphite has a thermal expansion start temperature of 240 ° C. or higher.
The content of the heat stabilizer with respect to 100 parts by mass of the polyvinyl chloride resin is higher in the intermediate layer than in the surface layer and the inner layer.
The molding temperature is 190 ° C or higher and lower than 240 ° C.
The surface layer, the intermediate layer, and the inner layer are laminated and extruded with a three-layer extrusion die, and then introduced into a sizing sleeve to shape the outer surface.
Manufacturing method of drainage piping material.

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