JP7444563B2 - Resin transparent fittings - Google Patents

Description

The present invention relates to a resin transparent joint.

In buildings such as apartment complexes, adjacent upper and lower floors are separated by floor slabs, and on each floor, two adjacent rooms are partitioned by walls. Piping materials such as drainage and water supply piping are installed through penetrations that penetrate floor slabs and walls. In order to prevent flames and smoke from flowing in when a fire breaks out in such a building, the gap between the inner surface of the penetrating portion and the piping material is filled with a sealing material such as mortar.

The piping material used for the above-mentioned penetration part is required to be resistant to deformation when heated for a predetermined period of time and resistant to holes (fire resistance). Patent Document 1 proposes a piping material containing thermally expandable graphite. When the piping material contains thermally expandable graphite, when a fire occurs and the temperature rises, the piping material expands and closes the penetrating portion, thereby preventing flames and smoke from flowing into the piping material.

Patent No. 4829847

There is a need to make the connection part (socket part) of a resin pipe joint transparent or translucent in order to visually check the inserted state of the pipe inside the joint when connecting the joint to another piping material.
However, the joint used in the piping material described in Patent Document 1 is not transparent.
Therefore, the object of the present invention is to provide a transparent resin joint that has excellent fire resistance and visibility.

The present invention has the following aspects.
<1> A resin product having a main body portion and a socket portion having a flow path inside, and containing a resin (R) containing one or more types selected from polyvinyl chloride resin and chlorinated vinyl chloride resin. In transparent joints,
contains powdered glass, the volume average particle diameter of the powdered glass is 1 to 100 μm,
The content of the powdered glass is 0.1 to 5.0 parts by mass with respect to 100 parts by mass of the resin (R),
The socket part is a resin transparent joint having a haze of 90% or less as measured in accordance with JIS K7361 (2000).
<2> The resin transparent joint according to <1>, wherein the content of the powdered glass is 0.1 to 5 parts by mass based on 100 parts by mass of the resin (R).
<3> The resin transparent joint according to <1> or <2>, wherein the powder glass has a refractive index of 1.4 to 2.0.
<4> The resin transparent joint according to any one of <1> to <3>, wherein the powdered glass is silica-based glass or phosphate-based glass powder.

According to the resin transparent joint of the present invention, it has excellent fire resistance and visibility.

FIG. 1 is a longitudinal cross-sectional view showing a resin transparent joint according to an embodiment of the present invention.

As used herein, "transparent or translucent" means that the inside of the joint can be visually recognized from the outside of the joint with the naked eye.
In this specification, fire resistance is evaluated by the evaluation method of the fire resistance performance test of the Revised Building Standards Act enforced on June 1, 2000.
In this specification, the numerical range represented by "~" means a numerical range that includes the numbers before and after "~" as the lower limit and upper limit.

[Resin transparent fitting]
Hereinafter, a resin transparent joint according to an embodiment of the present invention will be described based on the drawings.
A transparent resin joint 1 shown in FIG. 1 is a cheese-shaped transparent resin joint used for connecting a drain pipe.

The resin transparent joint 1 is, for example, a molded product obtained by injection molding a resin composition.
The transparent resin joint 1 has a tubular main body 10 having a flow path therein, and sockets 12 integrally formed in three openings 11 of the main body 10, respectively.
A tube member having an outer diameter that is approximately the same as the inner diameter of the socket portion 12 is inserted into the socket portion 12 . The inner diameter of the opening 12b of the socket 12 is larger than the inner diameter of the opening 11 of the main body 10.

The main body 10 of this embodiment has a straight pipe 10A and a branch pipe 10B. The straight pipe 10A is a substantially cylindrical tube coaxial with the first pipe axis O1. The straight pipe 10A has openings 11 in both directions of the first pipe axis O1. The branch pipe 10B branches from the side peripheral surface of the straight pipe 10A, and has an opening 11 at its tip.
The two socket portions 12 surround both openings 11 in the straight pipe 10A. Of these two socket parts 12, the one surrounding one opening 11 is the first socket part 12A, and the one surrounding the other opening 11 is the second socket part 12B. The first socket part 12A and the second socket part 12B are cylinders whose pipe axis is the first pipe axis O1.
One socket part 12 is a third socket part 12C that surrounds the opening 11 of the branch pipe 10B. The tube axis of the third socket portion 12C in this embodiment is the second tube axis O2. In this embodiment, the first tube axis O1 and the second tube axis O2 are orthogonal.
In FIG. 1, positions X and Y indicate the positions of gates for introducing the resin composition into the cavity (space) of an injection mold used when injection molding the resin transparent joint 1. A gate mark is formed on the resin transparent joint 1 at a position corresponding to the gate position X or Y.
The gate marks are formed at one or two locations selected from positions X and Y in FIG.

Residual stress is likely to be retained in gate marks. Residual stress is stress that remains inside the molded body after the molded body is heated and cooled. A molded body with large residual stress is easily deformed by heating. Therefore, the area around the gate mark of the transparent resin joint 1 is easily deformed by heating.
When the gate position is set to position X, there are no gate marks on the main body part 10 that are easily deformed by heat, so if the main body part 10 of the resin transparent joint 1 is buried in the penetration part of the fireproof compartment, fire resistance cannot be improved. Easy to improve. When the gate position is set to position Y, the distances from the gate to each socket part 12 are equal, making it easy to injection mold the resin transparent joint 1. Note that the position X may be located in any of the first socket part 12A, the second socket part 12B, and the third socket part 12C. In some cases, one or both of the two locations can be used as a gate. Moreover, the positions X and Y are illustrative, and the position X may be on the side surface of the socket part 12 instead of the end face part, and the position Y is the first socket part 12A, the second socket part 12B, It may be located anywhere on the main body 10 as long as it is at the same distance from the third socket 12C.

From the viewpoint of making the residual stress of the molded body uniform after molding and suppressing deformation due to heating, the thicknesses of the first socket part 12A, the second socket part 12B, and the third socket part 12C are uniform. It is preferable that there be.
The thicknesses of the first socket part 12A, the second socket part 12B, and the third socket part 12C are not particularly limited, but are preferably, for example, 2 to 8 mm, and more preferably 4 to 6 mm. When the thickness of the socket part 12 is equal to or greater than the above lower limit value, perforation due to heating of the socket part 12 can be easily suppressed. When it is below the above upper limit, the visibility of the socket portion 12 can be easily improved.
The thickness of the main body portion 10 is not particularly limited, and is preferably, for example, 6 to 12 mm, more preferably 8 to 10 mm. When the thickness of the main body part 10 is equal to or greater than the above lower limit value, perforation due to heating of the main body part 10 can be easily suppressed. When it is below the above upper limit, residual stress in the main body portion 10 can be easily suppressed.

The resin transparent joint 1 contains a resin (R) containing one or more selected from polyvinyl chloride resins and chlorinated vinyl chloride resins. The transparent resin joint 1 contains a resin composition containing resin (R). That is, the resin transparent joint 1 is manufactured by molding a resin composition. Usually, the resin transparent joint 1 is manufactured by injection molding a resin composition.
The resin-made transparent joint 1 may have a single-layer structure in which the entire resin composition is made of a resin composition, or may have a multi-layer structure made of a plurality of layers.

The resin transparent joint 1 is transparent or semitransparent. The total light transmittance of the transparent resin joint 1 is preferably 40% or more, more preferably 50% or more, even more preferably 60% or more, and particularly preferably 70% or more.
Total light transmittance refers to the ratio of total transmitted light flux to parallel incident light flux of a test piece made from a joint. The total light transmittance can be measured according to JIS K7361-1:1997 "Test method for total light transmittance of plastic transparent materials".

<Resin composition>
(Resin (R))
The resin composition contains a resin (R) containing one or more selected from polyvinyl chloride resins and chlorinated vinyl chloride resins.
Examples of polyvinyl chloride resins (PVC) include polyvinyl chloride homopolymers; copolymers of vinyl chloride monomers and other monomers having unsaturated bonds copolymerizable with the vinyl chloride monomers; polychlorinated Examples include graft copolymers obtained by graft copolymerizing vinyl chloride monomers onto polymers other than vinyl resins. One type of polyvinyl chloride resin may be used alone, or two or more types may be used in combination.

Other monomers having unsaturated bonds copolymerizable with the vinyl chloride monomer include, for example, 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 ether; (meth)acrylic acid esters such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl acrylate; aromatic vinyls such as styrene and α-methylstyrene; N-phenylmaleimide, N- Examples 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 to be graft-copolymerized with the vinyl chloride monomer include ethylene-vinyl acetate copolymer, ethylene-vinyl acetate-carbon monoxide copolymer, ethylene-ethyl acrylate copolymer, and ethylene-butyl acrylate monomer. Examples include carbon oxide copolymer, ethylene-methyl methacrylate copolymer, ethylene-propylene copolymer, acrylonitrile-butadiene copolymer, polyurethane, chlorinated polyethylene, and chlorinated polypropylene. These polymers may be used alone or in combination of two or more.

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

The average degree of polymerization of the polyvinyl chloride resin is preferably from 400 to 1,600, more preferably from 600 to 1,400, even more preferably from 600 to 900. Here, the average degree of polymerization is the average degree of polymerization measured in accordance with JIS K6720-2:1999 annex "Vinyl chloride resin test method".
When the average degree of polymerization of the polyvinyl chloride resin is at least the above lower limit, mechanical strength can be sufficiently increased, and when it is at most the above upper limit, sufficient moldability can be ensured.

The polyvinyl chloride resin may be further chlorinated. Examples of methods for chlorinating polyvinyl chloride resins include thermal chlorination methods, photochlorination methods, and the like.
Polyvinyl chloride resin is further chlorinated to become chlorinated vinyl chloride resin (CPVC).
CPVC includes thermally chlorinated vinyl chloride resins and photo-chlorinated vinyl chloride resins. Thermal chlorinated vinyl chloride resin is CPVC that has been chlorinated by heating, and the distribution of chlorine atoms in the molecule tends to be uniform. Photochlorinated vinyl chloride resin is CPVC that has been chlorinated by ultraviolet rays, and the distribution of chlorine atoms on the resin surface tends to be high.
The chlorine content of CPVC is 60 to 72% by mass, preferably 62 to 70% by mass, and more preferably 64 to 68% by mass. When the chlorine content of CPVC is at least the above lower limit, the fire resistance of the transparent resin joint 1 can be easily improved. When the chlorine content of CPVC is below the above upper limit, the moldability of the resin composition can be easily improved.

When the resin (R) contains CPVC, the content of CPVC relative to the total mass of the resin (R) is preferably 5 to 100% by mass, more preferably 10 to 90% by mass, and even more preferably 20 to 80% by mass. . When the content of CPVC is at least the above lower limit, fire resistance can be easily improved. When the content of CPVC is below the above upper limit, the moldability of the resin composition can be easily improved.

The resin (R) may contain resins other than polyvinyl chloride resin (PVC) and chlorinated vinyl chloride resin (CPVC). Other resins other than PVC and CPVC include polymers of the other monomers mentioned above.
The content of PVC and CPVC is preferably 85 to 100% by mass, more preferably 90 to 100% by mass, and even more preferably 100% by mass, based on the total mass of the resin (R). When the content of PVC and CPVC is within the above numerical range, it is easy to improve the fire resistance and the moldability of the resin composition.

(powder glass)
The material of the powder glass is not particularly limited, but examples thereof include alkali glass, bismuth glass, silica glass, and phosphate glass. Among these, silica-based glass and phosphate-based glass are preferred as the powdered glass.

The volume average particle diameter of the powdered glass is 1 to 100 μm, preferably 5 to 80 μm, and more preferably 10 to 50 μm. If the volume average particle diameter is equal to or larger than the above lower limit, the total light transmittance of the transparent resin joint 1 can be further increased, and the visibility can be further improved. If the volume average particle diameter is below the above upper limit, the strength of the resin transparent joint 1 can be increased.
The volume average particle size of the powdered glass is a value measured using a laser diffraction scattering particle size distribution measuring device.
In addition, when measuring the particle diameter of powdered glass after being molded into the resin transparent joint 1, it is calculated|required by the following procedure. The cross section of the resin transparent joint 1 is measured using a transmission electron microscope (TEM) or a scanning electron microscope (SEM), and the average length of the outer diameter of 50 glass particles present in the cross section is calculated. The obtained value is taken as the volume average particle diameter of the powdered glass.

The refractive index of the powder glass is not particularly limited, but is preferably 1.4 to 2.0, more preferably 1.5 to 1.7, and even more preferably 1.52 to 1.6. If the refractive index is within the above range, the refractive indexes of the powder glass and the polyvinyl chloride resin will be close to each other, so that the transparency of the resin transparent joint 1 can be increased and visibility can be further improved.

The content of powdered glass in the resin transparent joint 1 is 0.1 to 5.0 parts by mass, preferably 0.2 to 4 parts by mass, and 0.3 parts by mass, based on 100 parts by mass of resin (R). ~3 parts by mass is more preferred. If the content of powdered glass is at least the above lower limit, heat resistance can be further improved. If the content of powdered glass is below the above upper limit, the total light transmittance of the resin transparent joint 1 can be further increased, and visibility can be further improved.

(optional flame retardant)
The resin composition may contain any flame retardant (hereinafter sometimes simply referred to as "flame retardant") other than powdered glass. Examples of the flame retardant include inorganic hydroxides, antimony oxide compounds, molybdenum compounds, bromine compounds, phosphorus compounds, boric acid compounds, and mineral compounds. Examples of the inorganic hydroxide include magnesium hydroxide, aluminum hydroxide, and hydrotalcite. Examples of antimony oxide compounds include antimony dioxide, antimony trioxide, and antimony pentoxide. Examples of molybdenum compounds include molybdenum trioxide, molybdenum disulfide, and ammonium molybdate. Examples of bromine compounds include tetrabromobisphenol A and tetrabromoethane. Examples of the phosphorus compound include triphenyl phosphate and ammonium polyphosphate. Examples of boric acid compounds include calcium borate, zinc borate, and the like. Examples of mineral compounds include sepiolite, kaolinite, bentonite, and the like.
As the flame retardant, sepiolite is preferable because it has a high effect of suppressing the combustion of polyvinyl chloride resin.
One type of flame retardant may be used alone, or two or more types may be used in combination.

Inorganic hydroxide has an endothermic effect when heated and suppresses temperature rise. Therefore, these inorganic hydroxides function as flame retardants.
Magnesium hydroxide causes a dehydration reaction at temperatures above 300°C, so if magnesium hydroxide is used as an endothermic agent, a dehydration reaction may occur when molding the resin composition to produce the resin transparent joint 1. can be suppressed.
Since the dehydration reaction of aluminum hydroxide occurs at about 200° C., when aluminum hydroxide is used as an endothermic agent, the heat transmitted to the resin transparent joint 1 in the event of a fire can be quickly absorbed. Therefore, it is possible to further suppress deterioration of fire resistance due to deformation of the resin transparent joint 1 before the piping material thermally expands.

Hydrotalcite, whose chemical name is magnesium aluminum hydroxide carbonate hydrate, is a type of mineral represented by Mg ₆ Al ₂ (OH) ₁₆ CO ₃ .4H ₂ O and the like. Hydrotalcite is a layered inorganic material 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 ·mH2O] ^x- . It is a compound. Many divalent and trivalent metals have layered structures similar to this, and these are represented by the following general formula.
[M ²⁺ _1-x M ³⁺ _x (OH) ₂ ] ^x+ [A ^n- _x/n ·mH ₂ O] ^x- M ²⁺ : Divalent metal ion such as Mg ²⁺ or Zn ²⁺ .
M ³⁺ : Trivalent metal ion such as Al ³⁺ and Fe ³⁺ .
A ^n- : n-valent anion such as CO ₃ ^2- , Cl ^- , NO ₃ ^- .
X: 0<X≦0.33.

Hydrotalcite starts dehydrating the water of crystallization that it has between molecules at about 180°C, and the water of crystallization is completely eliminated at about 300°C. Until this state, synthetic hydrotalcite maintains its crystalline structure, but when the temperature exceeds about 350°C, the crystalline structure begins to collapse and releases water and carbon dioxide. Synthetic hydrotalcite starts endothermic decomposition at a temperature 60°C to 75°C lower than the thermal decomposition temperature of polyvinyl chloride resin, which is about 200°C to 300°C. can be effectively suppressed by endothermic decomposition of hydrotalcite.

Inorganic hydroxides are basic flame retardants. When a basic flame retardant is added to the resin transparent joint 1, the dehydrochlorination reaction of the polyvinyl chloride resin is promoted by the basic material. For this reason, a phenomenon called discoloration, in which the joint turns yellow, is more likely to occur. In addition, in order to make the resin composition transparent, it is necessary to reduce the particle size of the inorganic hydroxide, which increases the surface area of the inorganic hydroxide, making it easier to accelerate the dehydrochlorination reaction and causing discoloration. It becomes easier. Furthermore, if the joint is transparent, the discoloration inside the joint will be visible from the outside, making it more noticeable as color unevenness. The burnt resin absorbs light with a wavelength of 380 nm to 480 nm and appears yellow.
Therefore, in this embodiment, a colorant that absorbs light with a wavelength of 550 nm to 750 nm is used as the coloring agent described later, and is adjusted so that the absorption of light with a wavelength of 550 nm to 750 nm is greater than the absorption of light with a wavelength of 380 nm to 480 nm. This makes the yellow color caused by discoloration less noticeable, resulting in a joint with less uneven color.

The flame retardant is in particulate form.
The volume average particle size (hereinafter also simply referred to as particle size) of the flame retardant is 3 to 400 μm. When the particle size of the flame retardant is equal to or larger than the above lower limit, it is easy to make the transparent resin joint 1 transparent. When the particle size of the flame retardant is less than or equal to the above upper limit, the appearance of the transparent resin joint 1 can be easily improved.

The volume average particle size of the flame retardant can be measured in the same manner as the volume average particle size of powdered glass.

The BET specific surface area of the flame retardant is preferably 1 to 40 m ² /g, more preferably 1 to 20 m ² /g. Here, the BET specific surface area is a value determined using nitrogen adsorption.
When the BET specific surface area of the flame retardant is within the above numerical range, the effect as a flame retardant can be sufficiently exhibited, and the fire resistance of the resin transparent joint 1 can be improved. In addition, the occurrence of discoloration and color unevenness can be suppressed. Therefore, it is easy to improve the appearance of the resin transparent joint 1.

The particle surface of the flame retardant is preferably treated with a higher fatty acid such as stearic acid or a silane coupling agent. A flame retardant that has been surface-treated with a higher fatty acid or a silane coupling agent has higher dispersibility in polyvinyl chloride resin, and is more likely to exhibit its effect as a flame retardant.
When the flame retardant is surface-treated with a higher fatty acid or a silane coupling agent, the content of the higher fatty acid or the silane coupling agent is preferably 0.05 to 2 parts by mass based on 100 parts by mass of the flame retardant. When the content of the higher fatty acid and silane coupling agent is at least the above lower limit, the dispersibility of the flame retardant in the polyvinyl chloride resin can be sufficiently increased. When the content of higher fatty acids and silane coupling agents is below the above upper limit, costs can be reduced.

The content of the flame retardant is 0.1 to 1.0 parts by mass based on 100 parts by mass of the resin (R). When the content of the flame retardant is at least the above lower limit, fire resistance can be easily improved. When the content of the flame retardant is less than or equal to the above upper limit, the transparent resin joint 1 can easily be made transparent.

The content of the flame retardant can be appropriately determined depending on the particle size of the flame retardant.
For example, when the particle size of the flame retardant is 3 μm or more and less than 10 μm (a flame retardant with a particle size in this range is also referred to as flame retardant A), the content of the flame retardant is based on 100 parts by mass of the resin (R). It is preferably 0.1 to 0.3 parts by mass, more preferably 0.15 to 0.25 parts by mass. When the content of the flame retardant is at least the above lower limit, fire resistance can be easily improved. When the content of the flame retardant is less than or equal to the above upper limit, the transparent resin joint 1 can easily be made transparent.

When the particle size of the flame retardant is 10 μm or more and less than 100 μm (a flame retardant with a particle size in this range is also referred to as flame retardant B), the content of the flame retardant is 0.00 parts by mass based on 100 parts by mass of the resin (R). It is preferably 2 to 0.6 parts by weight, more preferably 0.3 to 0.5 parts by weight. When the content of the flame retardant is at least the above lower limit, fire resistance can be easily improved. When the content of the flame retardant is less than or equal to the above upper limit, the transparent resin joint 1 can easily be made transparent.

When the particle size of the flame retardant is 100 to 400 μm (a flame retardant with a particle size in this range is also referred to as flame retardant C), the content of the flame retardant is 0.5 parts by mass per 100 parts by mass of the resin (R). ~1.0 part by mass is preferred, and 0.6 to 0.9 part by mass is more preferred. When the content of the flame retardant is at least the above lower limit, fire resistance can be easily improved. When the content of the flame retardant is less than or equal to the above upper limit, the transparent resin joint 1 can easily be made transparent.

The particle size of the flame retardant can be appropriately determined depending on the type and purpose of the flame retardant used. For example, when sepiolite is used as a flame retardant, flame retardant A or flame retardant B is preferable.
When it is desired to improve the strength of the resin transparent joint 1, flame retardant A is preferable.
When it is desired to improve the transparency of the resin transparent joint 1, flame retardant C is preferable.

(Non-thermal expandable graphite)
The resin composition may contain non-thermally expandable graphite. As the non-thermally expandable graphite, artificial graphite, flaky graphite, lumpy graphite, earthy graphite, spheroidal graphite, etc. can be used.
When the resin composition contains non-thermally expandable graphite, the fire resistance of the resin transparent joint 1 can be more easily improved.
The non-thermally expandable graphite is preferably heat-dried before being mixed into the polyvinyl chloride resin.
That is, commercially available graphite has volatile matter attached to it, and this volatile matter evaporates due to a rise in temperature during molding, which may cause problems such as deterioration of the appearance of the molded product. In order to maintain a good appearance of the molded article, it is preferable to remove volatile components in advance by heat drying treatment.

Non-thermally expandable graphite is in particulate form.
The volume average particle size (hereinafter also simply referred to as particle size) of the non-thermally expandable graphite is preferably 3 to 400 μm. When the particle size of the non-thermally expandable graphite is equal to or larger than the above lower limit, the transparent resin joint 1 can easily be made transparent. When the particle size of the non-thermally expandable graphite is less than or equal to the above upper limit, the appearance of the transparent resin joint 1 can be easily improved.
The volume average particle size of non-thermally expandable graphite is determined in the same manner as the volume average particle size of powdered glass.

When the resin composition contains non-thermally expandable graphite, the content of the non-thermally expandable graphite is preferably 0.01 to 0.03 parts by mass based on 100 parts by mass of the resin (R). When the content of non-thermal expandable graphite is at least the above lower limit, fire resistance can be more easily improved. When the content of non-thermally expandable graphite is below the above upper limit value, the transparent resin joint 1 can easily be made transparent.

(colorant)
The resin composition may contain a colorant. Examples of pigment components contained in the colorant include blue dyes and pigments.
As the blue dye or pigment, inorganic or organic blue dyes or pigments known as blue colorants for resins can be used. The blue dye or pigment preferably has an absorption maximum in the wavelength range of 500 to 750 nm, particularly in the wavelength range of 550 to 700 nm, such as anthraquinone-based, azomethine-based, phthalocyanine-based, indigo-based blue dyes, Examples include pigments such as ultramarine blue, navy blue, cobalt blue, industhrene blue, and cerulean blue.

When the resin composition contains a colorant, the content of the colorant is preferably 0.005 to 0.030 parts by mass, and 0.010 to 0.025 parts by mass based on 100 parts by mass of the resin (R). The amount is more preferably 0.015 to 0.025 parts by mass. When the content of the colorant is at least the above lower limit, it is easy to obtain the transparent resin joint 1 with a desired color tone. When the content of the coloring agent is below the above upper limit value, the transparent resin joint 1 can easily be made transparent.

(stabilizer)
The resin composition preferably contains a stabilizer for the purpose of suppressing thermal decomposition of the polyvinyl chloride resin. Examples of the stabilizer include tin-based stabilizers, lead-based stabilizers, Ca--Zn-based stabilizers, higher fatty acid metal salts, and the like. One type of stabilizer may be used alone, or two or more types may be used in combination.
Examples of tin-based stabilizers include mercaptides such as dibutyltin mercapto, dioctyltin mercapto, and dimethyltin mercapto; malates such as dibutyltin maleate, dibutyltin maleate polymer, dioctyltin maleate, and dioctyltin maleate polymer; Examples include carboxylates such as tin mercapto dibutyltin laurate and dibutyltin laurate polymers.

Ca--Zn based stabilizers are mixtures of calcium salts of fatty acids and zinc salts of fatty acids. Examples of fatty acids include behenic acid, stearic acid, lauric acid, oleic acid, palmitic acid, ricinoleic acid, and benzoic acid, and two or more of these may be used in combination.
Examples of higher fatty acid metal salts include lithium stearate, magnesium stearate, calcium stearate, calcium laurate, calcium ricinoleate, strontium stearate, barium stearate, barium laurate, barium ricinoleate, cadmium stearate, and cadmium laurate. , cadmium ricinoleate, cadmium naphthenate, cadmium 2-ethylhexoate, zinc stearate, zinc laurate, zinc ricinoleate, zinc 2-ethylhexoate, lead stearate, dibasic lead stearate, lead naphthenate, etc. It will be done.
Among these, tin-based stabilizers or Ca--Zn-based stabilizers are preferred when making the transparent resin joint 1 transparent. As the tin-based stabilizer, those that do not contain sulfur, such as malates and carboxylates, are more preferable. As the Ca--Zn stabilizer, a stearate is more preferable from the viewpoint of the balance between lubricity and plate-out during molding.

When the resin composition contains a stabilizer, the content of the stabilizer is preferably 0.3 to 5.0 parts by weight based on 100 parts by weight of the resin (R). When the content of the stabilizer is at least the above lower limit, the thermal stability of the polyvinyl chloride resin during molding can be improved. When the content of the stabilizer is below the above upper limit, the polyvinyl chloride resin can be sufficiently carbonized during combustion, and sufficient fire resistance can be obtained.

(Other optional ingredients)
The resin composition may contain a lubricant, a processing aid, an impact modifier, a heat resistance improver, an antioxidant, a heat stabilization aid, an ultraviolet absorber, a plasticizer, a thermoplastic elastomer, within a range that does not impair the effects of the present invention. It may also contain additives (optional components) such as.
These optional components may be used alone or in combination of two or more.

When the resin composition contains an optional component, the content of the optional component is preferably 50 parts by mass or less, more preferably 30 parts by mass or less, and further preferably 20 parts by mass or less, based on 100 parts by mass of the resin (R). preferable.

The haze of the socket part 12 of the transparent resin joint 1 is 90% or less, preferably 85% or less, and more preferably 80% or less. If the haze is below the above upper limit, visibility is excellent. The lower limit value of the haze of the socket portion 12 is not particularly limited, but is substantially 10%.
The haze of the socket part 12 is adjusted by a combination of the type of powder glass, the amount of powder glass, the volume average particle diameter of the powder glass, the thickness of the socket part 12, the type of additives such as stabilizers, and the like.

The resin transparent joint of the present invention contains resin (R), contains a specific amount of powdered glass with a specific particle size, and has a haze of the socket within a specific range. Therefore, the resin transparent joint of the present invention has excellent fire resistance and visibility.
When the transparent resin joint of the present invention is used, it is easy to visually confirm the insertion state of the pipe inside the joint.

[Method for manufacturing transparent resin joints]
The resin transparent joint 1 is manufactured by injection molding.
For example, a resin transparent joint 1 containing resin (R) can be obtained by heating and melting a resin composition, injecting it into a mold, and then cooling it.

The heating temperature (molding temperature) of the resin composition in the injection molding machine is preferably 170 to 210°C, more preferably 180 to 190°C. When the molding temperature is within the above numerical range, thermal decomposition of the polyvinyl chloride resin can be suppressed to prevent a decrease in transparency, and a resin composition with good fluidity can be obtained by sufficiently melting the polyvinyl chloride resin.
The heating time in the injection molding machine is preferably 1 to 10 minutes. When it is at least the above lower limit, it can be sufficiently cured, and when it is at most the above upper limit, it is easy to improve the productivity of the resin transparent joint 1.

Although the resin transparent joint 1 of the present invention has been described in detail above, the present invention is not limited to the above embodiment, and can be modified as appropriate without departing from the spirit thereof.
The resin-made transparent joint may be a resin-made transparent joint having two or four sockets, such as an elbow, a nipple, or a cross, for example.

Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples.

(Examples 1-6, Comparative Examples 1-6, Reference Examples 1-2)
According to the compositions in Tables 1 to 3, 100 parts by mass of polyvinyl chloride (PVC, chlorine content 52% by mass) as the resin (R), a stabilizer or filler, and powdered glass were mixed in a Henschel mixer with an internal volume of 200 liters. (manufactured by Kawada Kogyo Co., Ltd.) to obtain a resin composition. In the table, ingredients whose amounts are not listed are not included.
The obtained resin composition was injection molded to produce a transparent resin joint similar to the cheese-shaped transparent resin joint shown in FIG. The molding temperature was 180°C, the mold temperature was 40°C, and the heating time was 120 seconds. At this time, the gates were located at the end face portions of the first socket portion 12A (two locations indicated by X in FIG. 1).
The haze was measured for the socket portion of the transparent resin joint of each example.
In addition, the visibility of the socket part of each example of the transparent resin joint was evaluated, the fire resistance was evaluated, and the overall evaluation was performed, and the results are shown in the table.

(Haze measurement method)
The socket portion of the transparent resin joint was cut into 25 mm square pieces, which were used as samples for haze measurement. Regarding the sample for haze measurement, haze was measured under the following conditions according to JIS K7361 (2000).
<Measurement conditions>
・Measuring equipment: V-570 ultraviolet-visible near-infrared spectrophotometer manufactured by JASCO Corporation.
・Optical system: Single monochromator double beam method.
・Measurement wavelength range: 190 to 2500 nm, 200 to 2000 nm (when using an integrating sphere).
・Light source: Deuterium lamp, halogen lamp.

(Evaluation method)
<Fire resistance>
A fire resistance test was conducted in accordance with the fire resistance performance test evaluation method of the revised Building Standards Act, which came into effect on June 1, 2000. Fire resistance was evaluated according to the following evaluation criteria.
≪(Evaluation criteria)≫
○: Fire resistance for 1 hour or more.
×: Fire resistance performance less than 1 hour.

<Visibility>
A resin pipe made of polyvinyl chloride resin (“Eslon Fireproof VP Pipe” manufactured by Sekisui Chemical Co., Ltd.) was inserted into the resin transparent joint of each example obtained, and the resin transparent joint and the resin pipe were connected. Transparency (visibility) was evaluated by visually observing the portion. Transparency was evaluated according to the following evaluation criteria.
≪Evaluation criteria≫
○: The connected portion is well visible, or there are some parts that are slightly difficult to see, but the connected portion is generally well visible.
×: Parts that are difficult to see are conspicuous, and the connected parts cannot be clearly seen.

<Comprehensive evaluation>
Comprehensive evaluation was performed according to the following evaluation criteria.
≪Evaluation criteria≫
〇: Evaluation of fire resistance and visibility is “〇”.
×: At least one of fire resistance and visibility evaluation is “×”.

As shown in Tables 1 to 3, Examples 1 to 6 to which the present invention was applied had an overall evaluation of "○".
Comparative Examples 1 to 6 with a haze of more than 90% had visibility of "x" and overall evaluation of "x".

1 Resin transparent joint 10 Main body 10A Straight pipe 10B Branch pipe 11 Opening 12 Socket 12A First socket 12B Second socket 12C Third socket 12b Opening O1 First pipe Shaft O2 Second tube shaft

Claims (2)

A transparent resin joint (R) that has a main body portion with a flow path inside and a socket portion, and contains a resin (R) containing one or more selected from polyvinyl chloride resins and chlorinated vinyl chloride resins . However, excluding those containing calcium carbonate) ,
containing powdered glass, the volume average particle diameter of the powdered glass is 10 to 30 μm,
The content of the powdered glass is 1.5 to 3.0 parts by mass based on 100 parts by mass of the resin (R),
The refractive index of the powder glass is 1.5 to 1.55,
The socket part is a resin transparent joint having a haze of 90% or less as measured in accordance with JIS K 7136:2000 . The resin transparent joint according to claim 1 , wherein the powder glass is a powder of silica-based glass or phosphate-based glass.

Images