JP5538994B2 - hose - Google Patents

Description

  The present invention relates to a hose that can be suitably used for, for example, toilets, kitchens, washstands, bathroom faucets, water storage tanks, dishwashers, water pipes, and other hot water and hot water supply pipes. .

  Conventionally, metal pipes mainly made of copper, stainless steel or the like have been used for piping for hot and cold water supply. However, since metal pipes are hard and inferior in flexibility, there is a problem that handling properties and workability are poor. Therefore, recently, instead of metal pipes, hoses that are fastened by caulking joint fittings to both ends of a hose made of a high-strength polymer material and a reinforcing layer made of metal wires or fibers are used as piping members. It has become.

  Moreover, the space where the water supply and hot water supply pipes are provided is relatively narrow, and in order to obtain good workability, the hose has to be excellent in flexibility. In addition, with the recent increase in the service life of houses, durability of water supply and hot water supply pipes is required more than ever. From such a point, the hose excellent in durability was requested | required, without impairing the softness | flexibility of a hose.

  As documents related to the present invention, for example, Patent Documents 1 to 6 are cited as references.

Patent No. 4280281: Nichirin Patent No. 4262882: Nichirin Patent No. 4152059: Togawa Rubber, Sumitomo Bakelite Patent No. 3893639: Bridgestone JP 2009-228753: Bridgestone JP2009-047268: Bridgestone

  In the past, in order to improve the durability of the hot and cold water supply hoses, polyolefin resins such as cross-linked polyethylene, polybutene, high density polyethylene, and polyethylene produced using a metallocene catalyst have been used as the innermost layer. In order to improve flexibility, elastomers, thermoplastic resins, and crosslinked polyolefin resins have been used as the outer layer of the inner layer tube.

  However, since the polyolefin used for the innermost layer as described above is a resin having a relatively high hardness, it is necessary to make the innermost layer thin in order to ensure flexibility. On the other hand, considering the durability, when the innermost layer is thinned, the durability cannot be significantly improved.

  The present invention has been made in order to solve such problems of the prior art, and the purpose thereof is to have flexibility excellent in handling property and workability, and durability has been remarkably improved. To provide a hose.

In order to achieve the above object, a hose according to claim 1 of the present invention has at least three layers including an innermost layer, a second inner layer adjacent to the innermost layer, and an outer layer disposed further outside the second inner layer. In the hose in which the tube composed of the above is disposed on the innermost side, the innermost layer and the second inner layer are both made of a polyolefin resin, the outer layer is made of a thermoplastic elastomer, and the hardness of the innermost layer is the second inner layer. The total thickness of the innermost layer and the second inner layer is 1.1 to 2.0 mm. The hose according to claim 2 is characterized in that the hardness of the innermost layer is 45D to 70D and the hardness of the second inner layer is 65A to 44D. The hose according to claim 3 is characterized in that the polyolefin resin used in the tube is selected from a crosslinked polyethylene resin, a crosslinked polyolefin resin, and a polybutene resin. The hose according to claim 4 is characterized in that, in the tube, the innermost layer and the second inner layer are formed by coextrusion and are co-crosslinked by electron beam irradiation. . The hose according to claim 5 is characterized in that the thermoplastic elastomer of the outer layer is a polyolefin-based thermoplastic elastomer or a polyurethane-based thermoplastic elastomer.
The hose according to claim 6 has a reinforcing layer or a reinforcing tube on the outer periphery of the inner tube.

  According to the present invention, flexibility during handling can be obtained, and durability can be remarkably improved.

It is a partially notched perspective view which shows the structure of the hose obtained by the Example of this invention.

  The innermost layer of the tube used in the present invention and the material of the second inner layer adjacent to the innermost layer are made of a polyolefin resin. Specifically, for example, ethylene, propylene, butene-1, hexene-1, 3methyl-butene-1, 4-methylpentene-1, heptene-1, octene-1, decene-1, dodecene-1, etc. A homopolymer of an α-olefin having 2 or more carbon atoms, a random or block polymer of these two or more types of monomers, or a random or block containing other α-olefins having 2 or more carbon atoms as a main component, Examples thereof include polymers such as grafts, and mixtures and cross-linked products thereof. Of these, a cross-linked polyethylene and ethylene-α-olefin copolymer mixture is preferable because the flexibility and durability of the tube can be easily controlled. Examples of polyethylene include high-density polyethylene, low-density polyethylene, and linear low-density polyethylene, and may be appropriately selected in consideration of flexibility and the like.

  It is possible to add other compounding materials to the innermost surface and the second inner layer of the tube used in the present invention to obtain desired characteristics. For example, the durability may be further improved by appropriately adding an anti-aging agent or the like.

  The total thickness of the innermost layer and the second inner layer of the tube is set to 1.1 mm to 2.0 mm. If the thickness is less than 1.1 mm, excellent durability cannot be obtained. If the thickness is more than 2.0 mm, the flexibility may be impaired depending on the hardness of the material. In consideration of flexibility, it is preferably set to 1.1 mm to 1.6 mm. Further, the thickness of the innermost layer is preferably set to 0.1 mm to 1.3 mm, more preferably 0.2 mm to 1.0 mm. If the innermost layer is less than 0.1 mm, the durability may be insufficient and the production may be difficult. Moreover, when the innermost layer exceeds 1.3 mm, flexibility may be impaired.

  In order to improve both durability and flexibility, the innermost layer is made of a material whose hardness is higher than that of the second inner layer. The innermost layer is preferably made of a material of 45D to 70D in order to improve durability, and is preferably made of a material of 45D to 60D in consideration of flexibility. In order to achieve both durability and flexibility, the second inner layer is preferably made of a material of 65A to 44D, and considering the durability, it is preferably made of a material of 70A to 44D. In addition, as a measuring method of hardness, it can measure using the spring type A type hardness meter or spring type D type hardness meter by JIS-K-7311.

  In the present invention, in order to integrate the innermost layer and the second inner layer, it is preferable that the innermost layer and the second inner layer are formed into a tubular shape by using a molding means such as coextrusion molding and co-crosslinked. The polyolefin resin as described above has a low heat-resistant temperature, and when used as a hot water supply hose, the temperature of the hot water transferred through the hose may reach about 90 ° C. This is because in some cases, it is necessary to increase durability at high temperatures by performing crosslinking. Examples of the cross-linking means include electron beam cross-linking, silane cross-linking, and peroxide cross-linking. In the present invention, it is preferable to employ electron beam cross-linking among these. The reason for this is that there is no need to blend other materials such as a crosslinking agent such as peroxide crosslinking and silane crosslinking, and the amount of components eluted into the fluid can be reduced, so that a material with a high degree of freedom can be selected. It is. From this point, in the present invention, it is most preferable to co-crosslink the innermost layer and the second inner layer by electron beam crosslinking.

  As described above, the present invention has a structure in which the relatively hard innermost layer and the relatively soft second inner layer are made of the polyolefin resin, which is the same material, and are adjacent to each other. Thus, since the innermost position is a relatively hard innermost layer, the hose of the present invention can improve durability. Furthermore, since the relatively soft second inner layer covers the innermost layer and has a structure that minimizes the innermost hard layer, durability can be improved without sacrificing flexibility. . In particular, when an anti-aging agent is added to the innermost layer and the second inner layer, even if the anti-aging agent in the innermost layer is gradually consumed over time in the usage environment, the second inner layer is also a similar material. The anti-aging agent can be smoothly transferred from the second inner layer to the innermost layer, and the durability can be further improved. Such migration of the anti-aging agent is particularly smooth when the innermost layer and the second inner layer are formed by coextrusion and are co-crosslinked. Also from such a viewpoint, it is preferable that the innermost layer and the second inner layer are formed by coextrusion and are co-crosslinked.

  In the present invention, an outer layer is provided on the outer side of the second inner layer. The material of the outer layer is preferably made of a thermoplastic elastomer and made of a material having excellent kink resistance and flexibility. Examples thereof include olefin-based elastomers, polyurethane-based elastomers, polyester-based elastomers, and styrene-based elastomers. Of these, polyolefin thermoplastic elastomers and polyurethane thermoplastic elastomers are particularly preferred. As the outer layer thermoplastic elastomer, a commercially available product can be used as it is, and durability may be further improved by appropriately adding an anti-aging agent or the like to the commercially available thermoplastic elastomer. The thickness of the outer layer may be appropriately set in consideration of kink resistance and flexibility. By using a thermoplastic elastomer for the outer layer, rubber elasticity that cannot be achieved only by polyolefin resin is imparted, and kink resistance can be improved. Note that another layer may be provided between the second inner layer and the outer layer or further outside the outer layer.

  In the present invention, it is preferable to form a reinforcing layer or a reinforcing tube on the outer periphery of the tube. Examples of the material constituting the reinforcing layer include linear bodies such as metal wires, monofilaments, and fiber yarns that are aggregates of fibers. With this reinforcing layer, a sufficient breaking pressure can be applied to the hose, and greater durability can be provided. The reinforcing layer is composed of a braid or winding of a linear body, but a braid is preferably used because there is little displacement of the reinforcing layer. Of course, the reinforcing layer may be a multilayer. As the reinforcing tube, a metal or resin tube, tube, coiled tube, bellows tube, braided tube, or the like is preferably selected.

  In the present invention, a cover layer may be formed on the outer periphery of the reinforcing layer. The constituent material of the cover layer is arbitrarily selected from known materials such as various resin materials, rubber materials, elastomer materials, etc., but kink resistance, abrasion resistance, scratch resistance, mechanical strength, oil resistance, A urethane-based polymer which is a material excellent in chemical properties, rubber elasticity and flexibility is preferred.

In order to further reduce the occurrence of kinks against bending, it is preferable to bond the cover layer and the linear body constituting the reinforcing layer in the present invention. By forming a cover layer containing a material of the same polymer as the thermoplastic polymer on the outside of the reinforcing layer including the linear body coated with the thermoplastic polymer, the cover layer is melt-bonded by heat at the time of forming the cover layer. Here, the same system refers to, for example, urethane systems, olefin systems, ester systems, nylon systems, and the like, and more specifically refers to a relationship such as a urethane elastomer and a urethane resin. From such a viewpoint, when the cover layer is a urethane polymer, the thermoplastic polymer coated on the linear body is composed of a composition containing a polyurethane elastomer or a polyurethane resin. Are preferably used.

  In addition, by forming such a cover layer, it is possible to further reduce the occurrence of kinks against bending, and it is difficult to get dust and dirt on the surface of the hose, and the surface can be easily cleaned. And the stain resistance can be improved.

  Many of the hoses obtained in this way are used for actual use with connecting joints attached to the opposite members at both ends thereof. As the connection joint, one processed by metal or resin is known.

  Thus, by appropriately setting the material, hardness, and thickness of each tube layer, both durability and flexibility are excellent.

  Embodiments of the present invention will be described below together with comparative examples with reference to the drawings.

Example 1
FIG. 1 is a cutaway perspective view of the water / hot water supply hose 1 of the present invention. First, a polyethylene resin and an ethylene-octene copolymer are mixed at a ratio of 90:10 so as to have a hardness of 52D, an anti-aging agent is added, and a material constituting the innermost layer 2a is obtained. Next, a polyethylene resin and an ethylene-octene copolymer are mixed at a ratio of 80:20 so that the hardness becomes 42D, an anti-aging agent is added, and a material constituting the second inner layer 2b is obtained. With these materials, the thickness of the innermost layer 2a is 0.3 mm, the thickness of the second inner layer 2b is 1.0 mm, and the total thickness of the innermost layer 2a and the second inner layer 2b is 1.3 mm. After coextrusion molding into a tubular shape, co-crosslinking is performed by irradiation with an electron beam. Then, a commercially available olefin-based elastomer was extruded and coated on the outer periphery of the second inner layer 2b as it was to form an outer layer 2c, and a tube 2 having a three-layer structure with a total thickness of 2.8 mm was obtained. On the tube 2, a maleic acid-modified olefin-based adhesive is applied. On the outer periphery, 6 polyester fibers having 1670 dtex and a twist number of 100 times / m were aligned, braided at 24 strokes (standing number) and a braid angle of 54 degrees, and the reinforcing layer 3 was formed on the outer periphery of the tube 2. Of the 6 polyester fibers, 3 are coated with polyurethane resin, and the remaining 3 are not coated with polyurethane resin. Next, a cover layer 4 was formed on the outer periphery of the reinforcing layer 3 by extrusion-coating a polyurethane elastomer so as to have a thickness of 0.95 mm. The hose 1 thus obtained had an inner diameter of 15 mm and an outer diameter of 24 mm.

Example 2
As a material constituting the innermost layer 2a, a polyethylene resin and an ethylene-octene copolymer are mixed at a ratio of 98: 2 so that the hardness is 70D. As a material constituting the second inner layer 2b, the hardness is 44D. The hose 1 was obtained by the same material, configuration, and production method as in Example 1 except that the polyethylene resin and the ethylene-octene copolymer were mixed at a ratio of 85:15. The hose 1 thus obtained had an inner diameter of 15 mm and an outer diameter of 24 mm.

Example 3
As the material constituting the innermost layer 2a, a polyethylene resin and an ethylene-octene copolymer are mixed at a ratio of 90:10 so that the hardness is 45D, and the hardness constituting the second inner layer 3b is 65A. Thus, the hose 1 was obtained by the same material, configuration, and production method as in Example 1 except that the polyethylene resin and the ethylene-octene copolymer were mixed at a ratio of 5:95. The hose 1 thus obtained had an inner diameter of 15 mm and an outer diameter of 24 mm.

Example 4
Example 1 except that the thickness of the innermost layer 2a is 0.2 mm, the thickness of the second inner layer 2b is 0.9 mm, and the total thickness of the innermost layer 2a and the second inner layer 2b is 1.1 mm. The hose 1 was obtained by the material, composition, and manufacturing method. The hose 1 thus obtained had an inner diameter of 15 mm and an outer diameter of 24 mm.

  Example 1 except that the thickness of the innermost layer 2a is 0.3 mm, the thickness of the second inner layer 2b is 1.7 mm, and the total thickness of the innermost layer 2a and the second inner layer 2b is 2.0 mm. The hose 1 was obtained by the material, composition, and manufacturing method. The hose 1 thus obtained had an inner diameter of 15 mm and an outer diameter of 24 mm.

  Moreover, the material which comprises the innermost layer in Example 1 was made into the 2nd inner layer, and what made the material which comprises the 2nd inner layer in Example 1 the innermost layer was made into the comparative example 1. Moreover, the material which comprises the innermost layer in Example 1 was made into the innermost layer, and the thing which did not provide the 2nd inner layer was made into the comparative example 2. The material constituting the second inner layer in Example 1 was used as the innermost layer, and the material without the second inner layer was used as Comparative Example 3. Moreover, about Example 1, what set the total thickness of the innermost layer and the 2nd inner layer to 1.0 mm was made into Comparative Example 4. Further, in Example 1, the total thickness of the innermost layer and the second inner layer was set to 2.1 mm as Comparative Example 5. The hoses 1 according to these comparative examples 1 to 5 had an inner diameter of 15 mm and an outer diameter of 24 mm.

  Using each hose thus obtained as a sample, tests for flexibility and durability were performed. For the flexibility test, the stress when bent to a radius of 100 mm was measured. For those with 40 N or less, ◎, for those that exceeded 40 N, but for those that had no problem in actual use, ○, over 40 N for actual use The problem was caused by Δ, and the case where bending was very difficult was marked by ×. As for the durability test, the time to breakage was confirmed by the chlorine water flow test. Those that did not break even after exceeding 9000 hours were broken in about 9000 hours. Those that do not have a good grade are marked as ◯, and those that need to be used for limited use before breaking down to 9000 hours are marked as Δ. The conditions for the chlorine water flow test were: liquid temperature: 90 ° C., chlorine concentration: 50 ppm, pH: 6.6.

  According to Table 1, the hot water and hot water supply hose according to the present invention has good results in both items of flexibility and durability.

  According to Table 1, from the result of Comparative Example 1, when the hardness of the second inner layer was higher than the hardness of the innermost layer, the flexibility was poor. From the result of Comparative Example 2, the flexibility was poor when the polyolefin resin layer was a single layer and was relatively hard (hardness 52D). Compared to Comparative Example 2, the polyolefin resin layer was made slightly soft (hardness 42D) in Comparative Example 3, but the flexibility was acceptable, but the durability was slightly insufficient. became. From the results of Comparative Examples 4 and 5, when the total thickness of the innermost layer and the second inner layer is less than 1.1 mm, the durability is slightly insufficient, and when it exceeds 2.0 mm, the flexibility is slightly poor. .

  As described above, the hose of the present invention has excellent flexibility and durability. Therefore, it can be suitably used in a wide range of applications such as toilets, kitchens, washstands, bathroom faucets, water storage tanks, dishwashers, water supply pipes, and other water supply and hot water supply pipes.

1 Hose 2 Tube 2a Innermost layer 2b Second inner layer 2c Outer layer 3 Reinforcing layer 4 Cover layer

Claims (6)

In the hose in which the tube consisting of three or more layers having at least the innermost layer, the second inner layer adjacent to the innermost layer, and the outer layer disposed further outside the second inner layer is disposed at the innermost side, Both the inner layer and the second inner layer are made of a polyolefin-based resin, the outer layer is made of a thermoplastic elastomer, the hardness of the innermost layer is harder than the hardness of the second inner layer, and the total thickness of the innermost layer and the second inner layer Is a hose characterized by being 1.1 to 2.0 mm. The hose according to claim 1, wherein the hardness of the innermost layer is 45D to 70D, and the hardness of the second inner layer is 65A to 44D. The hose according to claim 2, wherein the polyolefin resin used in the tube is selected from a crosslinked polyethylene resin, a crosslinked polyolefin resin, and a polybutene resin. 4. The hose according to claim 3, wherein in the tube, the innermost layer and the second inner layer are formed by coextrusion and are co-crosslinked by electron beam irradiation. 5. The hose according to claim 1, wherein the thermoplastic elastomer of the outer layer is a polyolefin-based thermoplastic elastomer or a polyurethane-based thermoplastic elastomer. 6. The hose according to claim 1, further comprising a reinforcing layer or a reinforcing tube on an outer periphery of the inner tube.

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