JP2580252B2 - Hot and cold water transfer pipe - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a hot water supply / drainage transfer pipe used for hot water supply / drainage and the like, and more particularly, to a water bubble having weather resistance and contact with halogen-containing water. The present invention relates to a hot water supply / drainage transfer pipe made of a crosslinked polyolefin resin, which prevents the occurrence of delamination, cracking, and the like.

[Conventional technology]

As the supply / drainage transfer pipe, a pipe made of a crosslinked polyolefin such as polyethylene, which has been crosslinked to impart heat resistance, has been used, and carbon black is further compounded, particularly when the transfer pipe is an exposed pipe. What has been provided with weather resistance is used.

However, in a water supply / drainage transfer pipe made of a crosslinked polyolefin resin containing carbon black, water (for the most part, chlorine) added to clean water for sterilization purposes causes water bubbles on the contact surface with high-temperature water after long-term use. Occurs, 30
An example in which delamination having a thickness of about 70 μm occurs was found.

[Problems to be Solved by the Invention] The conventional hot water supply / drainage transfer pipe made of a crosslinked polyolefin resin containing carbon black has the problem of the occurrence of water bubbles and delamination due to contact with halogen-containing water, though it has weather resistance. In addition, according to experiments performed by the present inventors, even in the case of a transfer tube containing no carbon black, in the case of a long-term use, deterioration is caused by halogen-containing water and fine cracks are formed inside. It was found to happen.

The present invention has been made to solve these problems in the hot and cold water transfer pipes. Therefore, the present invention has weather resistance and water bubbles caused by contact with halogen-containing water.
An object of the present invention is to provide a hot water supply / drainage transfer pipe in which the occurrence of delamination, cracks, and the like is prevented.

[Means for solving the problem]

The hot and cold water transfer pipe of the present invention is an azo type, phthalocyanine type, sulene type, dye lake, quinacridone type, dioxazine type, isoindolinone type organic pigment, and metal oxide type, molybdate chromate type, sulfide At least one colorant selected from inorganic selenide, ferrocyanide, and aluminum silicate pigments 0.02 to 7% by weight
And at least one stabilizer selected from an antioxidant and a light stabilizer in an amount of 0.005 to 2% by weight.

Here, the polyolefin resin is a low-density polyethylene, a medium-high-density polyethylene, and ethylene obtained by polymerization by a high-pressure method or a medium-low pressure method, and an α-olefin having about 3 to 20 carbon atoms, preferably butene-1, pentene-. Ethylene-α-olefin copolymer obtained by copolymerizing 1, hexene-1, 4-methylpentene-1 and octene-1 by an ionic reaction by a gas phase method, a solution method, a slurry method, a high pressure method or the like. (The α-olefin content is usually 0.5
-15% by weight), polypropylene obtained by polymerization by a gas phase method, a solution method, a slurry method, or the like, and propylene and an α-olefin having about 2 to 10 carbon atoms, preferably ethylene, butene-1, pentene- 1, a propylene-α-olefin copolymer obtained by copolymerizing hexene-1 with a gas phase method, a solution method, a slurry method, or the like, is a typical example.

The crosslinked polyolefin resin in the present invention refers to a so-called radiation crosslinking method of irradiating the polyolefin resin with an electron beam, γ-ray or the like, a so-called radiation crosslinking method, blending an organic peroxide or the like, and exposing it to a high temperature, a so-called chemical crosslinking method, unsaturated. It is obtained by crosslinking a silane compound to a gel fraction of 40% or more by a known crosslinking method such as a so-called water crosslinking method in which the silane compound is exposed to water.

As the colorant, specifically, for example, as an azo organic pigment, permanent red 2B, permanent yellow HR, permanent yellow H10G, brilliant carmine 6B, pigment scarlet 3B, pyrazolone red, polyazo red, monoazolet, polyazo Azo yellow, naphthol red, benzidine yellow, etc., phthalocyanine-based phthalocyanine blue, phthalocyanine green, etc., and sulene-based anthraquinone yellow, flavanthrone yellow, anthrapyrimidine, indanthrene blue, perylene red, thioindigo, etc. Examples of lakes include rhodamine lakes, quinacridones such as quinacridone, dioxazines such as dioxazine violet, and isoindolinones such as: Seo isoindolinone yellow, and the like, in Naka, phthalocyanine blue, phthalocyanine green, Anse La pyrimidine, indanthrenes blue, perylene red, quinacridone, dioxazine violet, isoindolinone yellow is preferred,
Phthalocyanine blue and perylene red are particularly preferred. The metal oxides of inorganic pigments include titanium white (rutile), titanium white (anatase), titanium yellow, iron black, red iron oxide, yellow iron oxide, chromium oxide green, cobalt blue, etc., and molybdate chromate. As, for example, graphite, molybdenum red, and sulfide selenide-based, cadmium red, cadmium yellow,
Examples of ferrocyanide compounds such as lithopone include navy blue and the like, and examples of aluminum silicates include ultramarine blue and the like. Among them, titanium white (rutile), titanium yellow, red iron oxide, yellow iron oxide, chromium oxide green, and cobalt blue , Cadmium red and cadmium yellow are preferred, and titanium white (rutile), titanium yellow, yellow iron oxide and cobalt blue are particularly preferred.

As the stabilizer, specifically, for example, as an antioxidant, 2,6-di-t-butyl-4-ethylphenol, n-octadecyl-β- (3,5-di-t-butyl) -4-hydroxyphenyl) propionate, 4,4'-
Thio-bis (3-methyl-6-t-butylphenol), 1,3,5-trimethyl-2,4,6-tris (3,5-di-
t-butyl-4-hydroxybenzyl) benzene, tetrakis [methylene-3- (3 ', 5'-di-t-butyl-
4'-hydroxyphenyl) propionate] methane,
1,3,5-tris (2,6-dimethyl-3-hydroxy-4-
t-butylbenzyl) isocyanurate, 3,5-di-t
-Butyl-4-hydroxyhydrocinnamic acid and 1,3,
Triester of 5-tris (2-hydroxyethyl) -s-triazine-2,4,6 (1H, 3H, 5H) -trione, 2-
t-butyl-4-methyl-6- (2'-hydroxy-
Phenolic compounds such as 3'-t-butyl-5'-methylbenzyl) phenyl acrylate, dilauryl-3,
Such as 3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropionate, and pentaerythritol-tetra (β-lauryl-thiopropionate); Sulfur compounds, tris (mixed, mono and dinonylphenyl) phosphite, distearylpentaerythritol diphosphite, tris (2,4-di-t-butylphenyl) phosphite, 4,4'-butylidene-bis (3-methyl-
6-t-butylphenyl-di-tridecyl) phosphite, tetrakis (2,4-di-t-butylphenyl)-
As a light stabilizer such as a phosphorus compound such as 4,4′-biphenylene phosphite, dimethyl-1- (2- (2-dimethylphenyl) succinate is used.
Hydroxyethyl) -2,2,6,6-tetramethyl-4-hydroxypiperidine polycondensate, poly [{6- (1,1,3,3
-Tetramethylbutyl) imino-1,3,5-triazine-
2,4-diyl {(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene {(2,2,6,6-tetramethyl-4-piperidyl) imino}], bis ( 2,2,6,6-
Hindered amine compounds such as tetramethyl-4-piperidyl) sebacate, tris (1,2,2,6,6-pentamethyl-4-piperidyl) -dodecyl-1,2,3,4-butanetetracarboxylate; (2'-hydroxy-
3'-t-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-
Benzotriazole compounds such as 3 ', 5'-di-t-butylphenyl) -5-chlorobenzotriazole;
Hydroxy-4-octadecyloxybenzophenone,
Benzophenone compounds such as 2,2'-dihydroxy-4-methoxybenzophenone, benzoate compounds such as 2,4-di-t-butylphenyl-3,5-di-t-butyl-4-hydroxybenzoate, ethyl- 2-cyano-
Cyanoacrylate compounds such as 3,5-diphenylacrylate; nickel compounds such as [2,2'-thio-bis (4-t-octylphenol)]-n-butylamine nickel; N- (4-ethoxycarbonylphenyl) −
Formamidine compounds such as N'-ethyl-N'-phenylformamidine and the like can be mentioned.

The hot and cold water transfer pipe of the present invention is characterized in that at least one of the coloring agents is contained in an amount of 0.02 to 7% by weight, preferably 0.02 to 7% by weight, based on the total amount of the compound.
0.1-3% by weight, at least one of said stabilizers is also 0.0
The crosslinked polyolefin resin is blended in an amount of from 0.05 to 2% by weight, preferably from 0.01 to 1% by weight. That is,
It is essential that both the coloring agent and the stabilizer are blended, and in the case of other blending agents, and when the blending amount of the coloring agent and the stabilizer is less than the lower limit, Cannot obtain the effect of the present invention. Even if the amount exceeds the upper limit, no further improvement in the required properties is observed.

In the production of the hot and cold water transfer pipe of the present invention, the colorant and the stabilizer are added directly or as a master batch to the polyolefin resin. It is performed by adding a wetting agent, a lubricant, an antistatic agent and the like, melt-kneading with an extruder, extruding into a tube, and performing a crosslinking treatment.

(Inventive effect)

The hot and cold water transfer pipe of the present invention is made of a crosslinked polyolefin resin, and a specific colorant and a stabilizer are mixed in a specific amount, so that it has weather resistance and water bubbles due to contact with halogen-containing water, Layered peeling, cracks and the like are prevented.

〔Example〕

Example 1 Low density polyethylene resin (Mitsubishi Petrochemical Co., Ltd., "Mitsubishi Polyethylene HE30", density 0.920g / cm ^3, MFR0.3g / 10 min), tetrakis [methylene-3- (3 as stabilizers ', 5' -Di-t
-Butyl-4'-hydroxyphenyl) propionate] methane (0.1% by weight) and granulated with an extruder having a diameter of 40 mm to obtain pellets. On the other hand, ethylene-butene-1 copolymer resin and titanium white (rutile) as a colorant
Is kneaded with a roll to prepare a master batch having a colorant concentration of 20% by weight, and the master batch is mixed with the pellets so as to have a final concentration of 1.0% by weight. Was extruded, and the tube was irradiated with an electron beam so as to have a gel fraction of about 80%, thereby producing a supply / drainage transfer pipe made of a crosslinked polyolefin resin.

A short tube having a length of 50 cm was cut out from the obtained tube, and a chlorine concentration of 100 ppm and 80 ° C. chlorine water were passed through the short tube at a flow rate of 10 / min for 30 days. , Observing the state of water bubbles on its inner surface,
The evaluation was made based on Fig. 4 of 14-56 (0 points; no abnormality-8 points; severely generated on the entire surface-10 points; peeling, 11 steps).

Then, the sample is placed on a fixed plate, compressed and deformed to 70% of the diameter with a parallel plate, and in this state, the parallel plate is moved to rotate the entire outer periphery of the sample while contacting the fixed plate. After repetition, the state of delamination and crack generation on the inner surface of the sample was observed and evaluated according to the following criteria.

Laminar peeling ○: No peeling observed ×: Peeling occurred on the entire surface Crack ○: No cracking observed △: Partially cracked ×: Cracking occurred on the entire surface On the other hand, the obtained tube was black-paneled with a sunshine weather meter By irradiating at a temperature of 83 ° C, 12 minutes / 60 minutes rainfall, 48 minutes / 60 minutes without rain for 2000 hours, cut out the dumbbell, measure the tensile elongation, and calculate the retention rate against the tensile elongation before irradiation. The weather resistance was evaluated.

 The evaluation results are shown in the table.

Example 2 High-density polyethylene (Mitsubishi Oil Chemicals "Mitsubishi Poly EY
40H ", density 0.952 g / cm ³ , MFR 1.5 g / 10 min) and tetrakis [methylene-3- (3 ', 5'-di-t-
Butyl-4'-hydroxyphenyl) propionate]
2.0% by weight of methane, 1% by weight of dibutyltin dilaurate as a condensation catalyst, and titanium white (rutile) as a colorant are kneaded with a roll to prepare a masterbatch having a colorant concentration of 20% by weight. 1.0
Crosslinkable polyethylene resin in a weight% (Mitsubishi Petrochemical Co., Ltd., "Link Ron HE707N", density 0.945g / cm ^3, MFR0.4g /
After mixing for 10 minutes), the nominal diameter 13 specified in JIS K 6761
Extrusion molding of polyethylene tubing
By immersing for hours, a supply / drainage transfer pipe made of a crosslinked polyolefin resin having a gel fraction of 72% was manufactured, and various characteristics were evaluated.

Example 3 Ethylene-butene-1 copolymer resin ("Mitsubishi Polyethylene-LL M 40F" manufactured by Mitsubishi Yuka Co., Ltd.) as a polyolefin resin,
Butene-1 content 7.5% by weight, density 0.922g / cm ³ , MFR 0.7g / 1
0 minutes), except that dicumyl peroxide was blended and crosslinked so as to obtain a gel fraction of about 80%. Was evaluated.

Example 4 A water supply / drainage transfer pipe was manufactured in the same manner as in Example 1 except that the colorant was changed to phthalocyanine blue, and various characteristics were evaluated.

Example 5 The stabilizer was poly [{6- (1,1,3,3-tetramethylbutyl) imino-1,3,5-triazine-2,4-diyl} (2,
2,6,6-tetramethyl-4-piperidyl) imino {hexamethylene} (2,2,6,6-tetramethyl-4-piperidyl) imino}] Water supply / drainage transfer pipes were manufactured and their characteristics were evaluated.

Example 6 A water supply / drainage transfer pipe was manufactured in the same manner as in Example 1 except that dimyristyl-3,3'-thiodipropionate was used as the stabilizer and the amount was changed to 0.02% by weight. Was evaluated.

Example 7 The stabilizer was 4,4'-thio-bis (3-methyl-6-t-
Butyl phenol), and except that the blending amount was changed to 0.02% by weight, a hot water supply / drainage transfer pipe was manufactured in the same manner as in Example 1, and various characteristics were evaluated.

Example 8 Poly [{6- (1,1,3,3-tetramethylbutyl) imino-1,3,5-triazine-2,4-diyl} as a stabilizer
{(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene} (2,2,6,6-tetramethyl-4-
A pipe for transferring hot and cold water was manufactured in the same manner as in Example 1 except that 0.1% by weight of piperidyl) imino was used in combination, and various characteristics were evaluated.

Comparative Example 1 The procedure of Example 1 was repeated except that the colorant was changed to 2.2% by weight of carbon black (furnace black, particle size: 20 μm).

Comparative Example 2 The procedure was the same as in Example 1 except that no coloring agent was added.

Comparative Example 3 The procedure was the same as in Example 3 except that no coloring agent was added.

Comparative Example 4 The procedure was the same as in Example 1 except that no stabilizer was added.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Koichi Kato 1 Toho-cho, Yokkaichi-shi, Mie Mitsubishi Plastics Co., Ltd. (72) Inventor Jiro Kurumi 1 Toho-cho, Yokkaichi-shi, Mie Mitsubishi Yuka Resin laboratory

Claims (1)

(57) [Claims] 1. An azo-based, phthalocyanine-based, selen-based, dye lake, quinacridone-based, dioxazine-based, isoindolinone-based organic pigment, metal oxide-based, molybdate chromate-based, sulfide selenide-based, 0.02 to 7% by weight of at least one coloring agent selected from ferrocyanide-based and aluminum silicate-based inorganic pigments, and 0.005 to at least one stabilizer selected from antioxidants and light stabilizers
A hot and cold water transfer pipe comprising a crosslinked polyolefin resin containing 2% by weight.