JP4697089B2 - Water pipe and manufacturing method thereof - Google Patents

Description

  The present invention relates to a water pipe and a method for manufacturing the same, and more particularly to a water pipe and a method for manufacturing the same that are excellent in non-contaminating property against a circulating fluid such as tap water and can improve workability on site. It is.

  Conventionally, metal pipes such as copper pipes and cross-linked polyethylene pipes have been used in water pipes that are mainly arranged inside buildings and supply tap water around the water in kitchens, bathrooms, toilets, etc. (for example, , See Patent Document 1). These water pipes are excellent in non-polluting to tap water (transfer of harmful components, odor attachment, discoloration, etc.), but in the case of metal pipes, processing such as bending, cutting and screwing in the field is possible. Since it is difficult, it is necessary to prepare and construct a shape pipe that matches the site in advance, and there is a problem that abrupt piping (arrangement and handling) cannot be changed on site.

  In addition, the cross-linked polyethylene pipe is easier to bend than the metal pipe, but it is easy to kink and is not sufficiently flexible, and it cannot be said that the workability on site is good. In particular, when the reinforcing layer is made of a stainless steel wire or the like, there is a problem that it cannot be joined to the metal fitting.

On the other hand, the rubber hose is excellent in flexibility and flexibility and easy to handle, but cannot be used because it cannot satisfy the required non-contaminating performance. A rubber hose with a resin layer on the innermost surface, specifically a nylon resin layer, can ensure good workability and improve non-contamination, but the components contained in the nylon resin layer must be extracted into tap water. Unnecessary taste and odor may be attached to the water pipe, and further improvement of the non-polluting property is necessary in the water supply piping which attaches great importance to the non-polluting property.
JP 2003-342981 A

  An object of the present invention relates to a water pipe and a method for manufacturing the same, and more specifically, a water pipe and a method for manufacturing the same that are excellent in non-contaminating property against a circulating fluid such as tap water and can improve workability on site. Is to provide.

In order to achieve the above object, the water supply pipe of the present invention has a reinforcing layer interposed between the inner rubber layer and the outer rubber layer that are coaxially laminated, and the innermost peripheral surface is a single nylon resin layer. It is a water supply pipe, the layer thickness of the nylon resin layer is 0.08 mm or more and 0.20 mm or less, the nylon resin forming the nylon resin layer is non-plastically blended, and the oligomer component content is 1.0 wt% %, The inner rubber layer laminated on the outer peripheral surface of the nylon resin layer has a layer thickness of 0.5 mm or more and 3.0 mm or less, and the rubber is made non-plastically blended , and the inner rubber layer is configured. The rubber composition has a 100% modulus of 4.0 MPa to 10.0 MPa .

Further, the water pipe manufacturing method of the present invention includes a reinforcing layer interposed between an inner rubber layer and an outer rubber layer laminated coaxially, and an innermost peripheral surface having a layer thickness of 0.08 mm or more and 0.20 mm. The following one nylon resin layer, the inner rubber layer having a layer thickness of 0.5 mm or more and 3.0 mm or less, the inner rubber layer being non-plastically blended , and a rubber composition constituting the inner rubber layer A water pipe manufacturing method in which 100% modulus of a product is 4.0 MPa or more and 10.0 MPa or less, and an oligomer component is forced by immersing a non-plastic blended nylon resin in methanol heated to 95 ° C. or more for a predetermined time. The nylon resin layer is formed with this nylon resin, and a member layer constituting the water pipe is sequentially laminated on the outer peripheral surface of the nylon resin layer. After molding the molded article, vulcanizing molded article, when laminating the inner rubber layer on an outer peripheral surface of the nylon resin layer, the adhesive in a concentration from 9.0 to 17.0% of the phenolic resin-based adhesive It is characterized by making it.

  According to the present invention, the inner surface is provided with a nylon resin layer made of a nylon resin that is non-plastically blended and has an oligomer component content of 1.0 wt% or less on the innermost peripheral surface that is in contact with a circulating fluid such as tap water. The nylon layer can prevent contamination (transfer of components, odor attachment, discoloration, etc.) to the circulating fluid due to the rubber layer, and the components contained in the nylon resin layer itself can be prevented from being extracted into the circulating fluid. It becomes possible to prevent contamination (taste, smell, etc.) to the fluid.

  In addition, since the main components of water pipes are rubber and resin, they are more flexible and flexible than metal water pipes, so the degree of freedom of pipes is increased and cutting and joining with metal fittings are easy. This improves workability on site.

  Hereinafter, the water supply pipe and its manufacturing method of the present invention will be described based on the embodiments shown in the drawings.

  As illustrated in FIG. 1, the water pipe 1 of this embodiment has a structure in which a nylon resin layer 2, an inner rubber layer 3, a reinforcing layer 4, and an outer rubber layer 5 are coaxially laminated in order from the inner peripheral side. It has become. The reinforcing layer 4 formed by braiding fibers is provided in one layer, and the nylon resin layer 2 is formed of a nylon resin containing no plasticizer and having an oligomer component content of 1.0 wt% or less.

  In this way, the innermost peripheral surface through which a circulating fluid such as tap water flows becomes the nylon resin layer 2, and the circulating fluid has a structure that does not contact the rubber of the inner rubber layer 3. The transfer of harmful components to the circulation fluid is blocked by the nylon resin layer 2. For this reason, contamination (transfer of components, attachment of odor, discoloration, etc.) to the circulating fluid by the inner rubber layer 3 is prevented.

  Furthermore, in the present invention, by forming the nylon resin layer 2 from a non-plastically blended nylon resin, the component of the plasticizer that attaches unnecessary taste to the circulating fluid is not extracted into the circulating fluid, and the nylon resin layer 2 Due to this, there is no need to add unnecessary taste to the circulating fluid. In addition, since this nylon resin reduces the oligomer component of the nylon resin that causes unnecessary odors to adhere to the circulating fluid to 1.0 wt% or less, it is suppressed to a state in which this oligomer component is hardly extracted into the circulating fluid. An unnecessary odor is not attached to the circulating fluid due to the nylon resin layer 2. In this way, contamination of the circulating fluid by not only the inner rubber layer 3 but also the nylon resin layer 2 itself can be prevented, and excellent non-staining properties are obtained.

  In addition, compared to metal water pipes, it is rich in flexibility and flexibility, and the degree of freedom in handling the pipes during construction is increased, and it is easy to cut water pipes 1 and join them to metal fittings. This improves workability on site.

  Examples of the nylon resin used for the nylon resin layer 2 include 6 nylon (N6), 66 nylon (N66), 11 nylon (N11), 12 nylon (N12), and the like. In particular, 11 nylon is preferable because it is excellent in water resistance and is easy to extrude.

The layer thickness of the nylon resin layer 2 is preferably 0.05 mm or more and 1.0 mm or less. If the layer thickness is within this range, the inner rubber layer 3 is non-contaminating to tap water (transfer of harmful components, odor attachment, discoloration, etc. ) And bending rigidity can be satisfactorily achieved. More preferably, as in the present invention, a layer thickness of 0.08 mm or more and 0.20 mm or less has a good balance in both non-contamination and bending rigidity.

  Various rubber compositions can be used for the inner rubber layer 3, such as styrene-butadiene copolymer rubber, butadiene rubber, butyl rubber, ethylene-propylene copolymer rubber, ethylene-propylene-diene copolymer rubber. Examples thereof include a rubber composition containing as a main component at least one of chloroprene rubber, ethylene copolymer rubber, and acrylonitrile-butadiene copolymer rubber. Various rubber compositions can be used for the outer rubber layer 5. For example, the same rubber composition as the inner rubber layer 3 described above can be used.

Rubber inner rubber layer 3 and rubber unplasticized formulation that does not incorporate plasticisers. Thereby, the component of the plasticizer does not migrate and permeate from the inner rubber layer 3 to the nylon resin layer 2, and it is possible to maintain excellent non-contamination property against the circulating fluid for a long time.

  The reinforcing layer 4 is not limited to those exemplified in the above embodiment, and the reinforcing layer 4 can be formed in a plurality of layers through an intermediate rubber layer depending on use conditions such as water pressure, and the fibers are spirally wound. It can also be.

When the end of the water pipe 1 is joined to an SL metal fitting (socketless metal fitting), it is required to be easily mounted (metal fitting insertion property) and hard to come off from the joined metal fitting (detachment resistance). . In order to satisfy both of these performances, it is preferable to form the reinforcing layer 4 by braiding the reinforcing yarn 4a having a breaking elongation of 15% or less within a range of a braid angle A of 49.4 ° or more and 52.2 ° or less, and an internal rubber. to 100% modulus of the rubber composition constituting the layer 3 below 10.0MPa than 4.0 MPa.

  In the present invention, the breaking elongation of the reinforcing yarn 4a is based on the measurement based on JIS L 1017, and the 100% modulus of the rubber composition is based on the measurement based on JIS K 6251.

  If the breaking elongation of the reinforcing thread 4a exceeds 15%, the expansion of the water pipe 1 when the internal pressure increases cannot be sufficiently suppressed, and the water pipe 1 is easily pulled out. When the braid angle A of the reinforcing yarn 4a is 49.4 ° or more and 52.2 ° or less, the deformation of the water pipe 1 is moderately suppressed, and the metal fitting insertion property and the slip-out resistance can be improved. Examples of the reinforcing yarn 4a include vinylon and aramid fibers.

Furthermore, the 100% modulus of the rubber composition constituting the inner rubber layer 3 and the outer rubber layer 5 has an influence on the slip resistance, and the inner rubber layer 3 has a particularly large influence. When the 100% modulus of the rubber composition constituting the inner rubber layer 3 is less than 4.0 MPa, it is difficult to obtain sufficient metal fitting resistance. On the other hand, when it exceeds 10.0 MPa, the inner surface rubber layer 3 becomes difficult to be deformed, and the metal fitting insertion property is lowered. The layer thickness of considering the flexibility and resistance to leakage resistance and inner rubber layer 3 is in the range of 0.5 mm to 3.0 mm.

  The 100% modulus of the rubber composition constituting the outer rubber layer 5 is particularly preferably 1.5 MPa or more and 10.0 MPa or less, and the layer thickness is 0.5 mm to 3 in consideration of flexibility and slipping resistance. Preferably it is in the range of 0.0 mm.

  As described above, by specifying the specifications of the reinforcing layer 4 and the 100% modulus of the rubber composition of the inner rubber layer 3, it is easy to insert the SL metal fitting into the water pipe 1 and prevent it from coming off. it can. Thereby, construction becomes easy and the construction period can be shortened.

Next, a method for manufacturing the water pipe 1 illustrated in FIG. 1 will be described. First, a non-plastically blended nylon resin is subjected to a purification treatment by immersing it in methanol heated to a predetermined temperature, that is, 95 ° C. or higher for a predetermined time, for example, 10 hours to forcibly extract the oligomer component of the nylon resin. The content is reduced to 1.0 wt% or less.

  Thus, it is preferable to make the specification which has the antifouling property (taste and smell) which satisfies FDA (US food hygiene standard) by performing the above refinement | purification processes to the nylon resin of a non-plastic mixing | blending.

  Next, a resin tube made of an unplasticized nylon resin subjected to the purification treatment is extruded on a mandrel to form a nylon resin layer 2, and an inner rubber layer 3 is laminated on the outer peripheral surface of the nylon resin layer 2. Then, the reinforcing layer 4 and the outer rubber layer 5 are sequentially laminated on the outer peripheral surface to produce a molded product. Next, the molded product is vulcanized at a temperature at which the resin tube does not melt, and the water pipe 1 can be manufactured by pulling out the mandrel after the vulcanization step. Therefore, a general rubber hose manufacturing facility can be used as it is, and a significant addition of equipment and cost is not necessary.

In this manufacturing process, the nylon resin layer 2 and the inner rubber layer 3 are bonded using a phenolic resin adhesive that has a strong adhesive force even when diluted to a low concentration . The concentration of the phenolic resin-based adhesive at that time to 9.0 to 17.0%. Accordingly, the nylon resin layer 2 and the inner rubber layer 3 can be firmly bonded with a small amount of adhesive to prevent delamination. Furthermore, since the components of the adhesive are greatly diluted, it is possible to more reliably prevent the contamination of the circulating fluid that occurs when the adhesive component permeates the nylon resin layer 2.

  FIG. 2 shows another embodiment of the water pipe 1. This water pipe 1 is provided with a cover resin layer 6 on the outer peripheral surface of the outer rubber layer 5 of the water pipe 1 illustrated in FIG. 1, and the other specifications are the same. The water pipe 1 can be manufactured by adding a process of laminating the cover resin layer 6 on the outer peripheral surface of the outer rubber layer 5 to the manufacturing process of the water pipe 1 described above.

  Examples of the resin used for the cover resin layer 6 include polyvinyl chloride and polyurethane, and the layer thickness is preferably 0.5 mm or more and 3.0 mm or less. By providing the cover resin layer 6 having a layer thickness of 0.5 mm or more on the outermost periphery, the cover resin layer 6 prevents the outer surface rubber layer 5 from being deteriorated by ultraviolet rays even in a use environment exposed to sunlight or the like. Weather resistance can be improved. Moreover, the process of joining a plurality of water pipe hoses or joining metal fittings becomes easy by joining the cover resin layers 6 of the water pipes 1 to each other. On the other hand, by setting the layer thickness of the cover resin layer 6 to 3.0 mm or less, excellent flexibility can be secured without significantly increasing the bending rigidity of the water pipe 1.

  5 types of test bodies having the same structure as the water pipe illustrated in FIG. 2 except for the presence / absence of the plasticizer and the oligomer component content of the nylon resin layer on the innermost peripheral surface (Examples 1, 2 and Comparative Example 1) -3) Manufactured. 11 nylon with a layer thickness of 0.10 mm for the nylon resin layer, acrylonitrile butadiene rubber with a layer thickness of 2.0 mm for the inner rubber layer, two spiral layers of vinylon for the reinforcing layer, and acrylonitrile butadiene rubber with a layer thickness of 1.6 mm for the outer rubber layer, The cover resin layer is made of polyvinyl chloride having a layer thickness of 1.0 mm, the nylon resin layer and the inner rubber layer are diluted with phenol resin adhesive (Ty-PlyBN manufactured by Road Far East Incorporated) with methyl ethyl ketone to 17.0%. The common condition was that the materials were bonded at a concentration. These five types of test specimens were evaluated for the following taste and odor, and the evaluation results are shown in Table 1.

  In addition, the content rate of the oligomer component of the nylon resin which forms the nylon resin layer of each test body shown in Table 1 was measured according to the method described in JIS K 6229-1998 “Quantification of rubber-solvent extract”. The extraction amount (wt%) of the oligomer component of the nylon resin obtained by measurement at a methanol heating temperature of 95 ° C. and an extraction time of 10 hours is displayed.

[Evaluation of taste and smell]
Evaluation is conducted in accordance with Annex 16 (Taste Analysis Method) and Annex 17 (Odor Analysis Method) of JIS S 3200-7-2004 “Water Supply Equipment—Leaching Performance Test Method”. C. warm water (tap water) was sealed and allowed to stand for 16 hours, and then the warm water was taken out and evaluated by heating the taken warm water to 40.degree. Regarding the taste, the mark indicates that the evaluator felt tasteless, the mark △ indicates that the taste is other than water, and the mark indicates the taste that is clearly tasted other than water. It was. Odors are indicated by ○ when the evaluator feels odorless, indicated by △ when odors other than water are felt slightly, and indicated by × when odors other than water are clearly felt. It was. As a comprehensive evaluation, for both taste and odor, the case of evaluation of ○ mark is indicated by ○ mark, and the other cases are indicated by × mark.

  From these results, in Examples 1 and 2 in which the nylon resin layer was formed of an unplasticized nylon resin and the oligomer component content of the nylon resin was 1.0 wt% or less, the nylon resin layer was added to the enclosed warm water. Since there was no extraction of the components from the above, it was confirmed that it was tasteless and odorless and excellent in non-contamination performance against the circulating fluid.

1 is a partially cut perspective view illustrating a water pipe according to the present invention. FIG. 6 is a partially cutaway perspective view illustrating another embodiment of the water pipe according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Water supply pipe 2 Nylon resin layer 3 Inner surface rubber layer 4 Reinforcement layer 4a Reinforcement thread 5 Outer surface rubber layer 6 Cover resin layer

Claims (4)

A water pipe having a reinforcement layer interposed between an inner rubber layer and an outer rubber layer laminated in a coaxial manner and having an innermost peripheral surface as one nylon resin layer, the layer thickness of the nylon resin layer 0.08 mm or more and 0.20 mm or less, and the nylon resin forming the nylon resin layer is made non-plastically blended, and the oligomer component content is 1.0 wt% or less, and is laminated on the outer peripheral surface of the nylon resin layer. The inner rubber layer has a thickness of 0.5 mm or more and 3.0 mm or less, the rubber is made into a non-plastic compound , and the 100% modulus of the rubber composition constituting the inner rubber layer is 4.0 MPa or more. Water pipes set to 10.0 MPa or less .   The water supply pipe according to claim 1, wherein one cover resin layer is provided on the outer peripheral surface of the outer rubber layer, and the thickness of the cover resin layer is 0.5 mm or more and 3.0 mm or less. The water pipe according to claim 1 or 2, wherein the reinforcing layer is formed by braiding a reinforcing yarn having a breaking elongation of 15% or less in a braid angle range of 49.4 ° to 52.2 °. A reinforcing layer is interposed between the inner rubber layer and the outer rubber layer laminated coaxially, and the innermost peripheral surface is a single nylon resin layer having a layer thickness of 0.08 mm or more and 0.20 mm or less. The layer thickness of the rubber layer is 0.5 mm or more and 3.0 mm or less, the inner rubber layer is non-plastically blended , and the 100% modulus of the rubber composition constituting the inner rubber layer is 4.0 MPa or more and 10. A method for producing water pipes of 0 MPa or less, in which an oligomer component is forcibly extracted by immersing an unplasticized nylon resin in methanol heated to 95 ° C. or more for a predetermined time, so that the content is 1.0 wt%. The nylon resin layer is formed with this nylon resin, the member layer constituting the water pipe is sequentially laminated on the outer peripheral surface of the nylon resin layer, and the molded product is molded. vulcanizing , When stacking the inner rubber layer on an outer peripheral surface of the nylon resin layer, the manufacturing method of the water pipes to be bonded at a concentration from 9.0 to 17.0% of a phenolic resin based adhesive.

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