JP3814732B2

JP3814732B2 - Rubber ring provided at the joint of vinyl chloride pipe

Info

Publication number: JP3814732B2
Application number: JP20219797A
Authority: JP
Inventors: 謙一南; 誠治樋田
Original assignee: Nitto Kako Co Ltd
Current assignee: Nitto Kako Co Ltd
Priority date: 1997-07-11
Filing date: 1997-07-11
Publication date: 2006-08-30
Anticipated expiration: 2017-07-11
Also published as: JPH1130370A

Description

【０００１】
【産業上の利用分野】
本発明は、上下水道或は地中線埋設に使用される塩化ビニル管の接合部、例えば、下水道用の塩化ビニル管の円形の塩化ビニル管、直管、枝付本管、タマゴ形の直管、受口カラ−、推進管のゴム輪形ＳＵＳカラ−付直管に使用されるゴム輪と下水道用の塩化ビニル管のゴム輪受口曲管用継手、自在曲管継手、Ｖ型自在継手取付用継手、円形管マンホ−ル継手、タマゴ形マンホ−ル継手、小口径排水マス用、小口径公共マス用、小口径マンホ−ル用、円形支管、ヒュ−ム管用支管、陶管用支管、玉子形支管等に用いられる塩化ビニル管の接合部に設けるゴム輪に関するものである。
【０００２】
【従来の技術】
従来、一般に管受口内に管差口を挿入して管を接合する場合、管受口内面と管差口外面との間に水密用ゴム輪を圧縮介入させることが行なわれる。
この水密用ゴム輪の圧縮介入は通常予め管受口内面にゴム輪を配設しておき、この中に管差口を強制的に挿入することにより実施されるが、管差口の挿入時に前記ゴム輪を径方向に圧縮させる必要上、管挿入に際して非常に強大な挿入圧力を必要とする。塩化ビニル管メ−カ−は、管挿入時の作業が容易に行われ且つ止水効果が良好であるゴム輪の形状に苦慮しているところである。一例として、塩化ビニル管では約２００ｋｇという非常に強大な挿入荷重を受ける場合もある。
【０００３】
このため、斯かる挿入時の摩擦抵抗を軽減し、かつ、挿入時のゴム輪の転動を防止する見地より管差口外面およびゴム輪内面に滑剤を塗布することが行なわれる。この滑剤は、缶容器等に納められており、使用に際し、缶容器から滑剤を取り出してゴム輪の管差口に接する面に塗着している。
【０００４】
また、斯かる挿入時の摩擦抵抗を軽減し、かつ、挿入時のゴム輪の転動を防止するため、管差口外面に接する面に摩擦係数の低い樹脂コ−ティング層を設けたゴム輪が提供されている。この樹脂コ−ティング層の樹脂としては、テフロン樹脂、シリコ−ン樹脂、ウレタン樹脂或はハロゲン樹脂からなる樹脂が用いられている。
【０００５】
【発明が解決しようとする課題】
前記の従来の技術で説明したもののうち、前者の滑剤を塗着する方法では、塩化ビニル管の挿入に対する挿入荷重を４．０ｋｇとすることができるとしても、滑剤の塗布作業は配管作業現場で、ゴム輪に一個ごとに行わなければならないので、滑剤の塗布作業に多くの時間と労力が要求されている。しかも、上記滑剤は一般にゼリ−状をなすから塗布面には砂粒等の異物が付着しやすく、砂粒等が付着すればこれが漏水の原因となるため、塗布作業には周囲の環境に厳重な注意を要する上、塗布作業は、現場作業となることから、通常屋外作業となるので雨中あるいは水中での作業においては塗布した滑剤が流し落され、また、高温乾燥の気象条件下では滑剤が乾き易いため接続作業を迅速に行なわねばならないなど困難な制約が多いといった課題があった。この一例として、塩化ビニル管小口径排水マス及び公共マス用の管差口に、ゴム輪付きのプラグ部品のゴム輪に滑剤を使用して、このプラグ部品を管差口にキャップをしておき、将来配管延長があった場合、プラグを引き抜いて、管差口に接着剤を用いて直管を接合すると、プラグを管差口にキャップしたときのゴム輪に残存する滑剤が接着剤に悪影響をもたらし十分な接合力を得られない場合があった。
【０００６】
更に、滑剤は人畜無害な物質とされているものの管接続後、洗管できない場合等では該滑剤が内部流体に溶け出し、内部流体、例えば水道水を濁らせると言った問題があった。
【０００７】
また、後者の樹脂コ−ティング層を形成したゴム輪にあっては、作業現場でゴム輪に一個ごとに滑剤を塗布する面倒な作業を不要とするとしても、塩化ビニル管に対する挿入荷重が、前者の滑剤を塗布した場合に比し、大きいために、挿入作業が困難であり、それ故に、樹脂コ−ティング層に滑剤を補足塗布して使用されており、折角設けられた樹脂コ−ティングされた滑面は塩化ビニル管の挿入荷重を軽減するための機能を十分に果たし得ないという課題があった。更に、この樹脂コ−ティング層は、内容組成物が塩化ビニル管に移行しやすく変色が起こり、塩化ビニル管を侵す原因となっていた。
【０００８】
本発明の目的は、上記の課題に鑑みてなされたものであって、その目的とするところは、塩化ビニル管の管接続に際し、現場での滑剤の塗布作業を必要とせず、塩化ビニル管の挿入荷重を、滑剤を塗布使用した場合と同等として、管接続を容易になし得るようにし、塩化ビニル管への影響が少なく、しかも特定の樹脂を使用し製造上安価かつ容易に成形すると共に寿命の長いゴム輪を提供するものである。
【０００９】
【課題を解決するための手段】
上記目的を達成するために、本発明に係る塩化ビニル管の接合部に設けるゴム輪は、管受口内面とビニル管の差口外面との間に圧縮介入されるゴム輪において、前記ビニル管の差口外面に接する面にポリテトラフルオロエチレン、アクリル変性ポリエステルとポリイソシアネ−トを用いた樹脂コ−ティング層を設けてなる。
【００１０】
また、前記ゴム輪は、前記ビニル管の差口外面に接する面にポリテトラフルオロエチレン３〜２５重量％、アクリル変性ポリエステル５〜６０重量％および溶剤よりなる主剤１００重量部とポリイソシアネ−ト３〜４５重量％および溶剤よりなる硬化剤１０〜３０重量部を用いて混合した反応液を室温から１５０℃で１秒から３０分熱硬化した樹脂コ−ティング層を設けてなる。
【００１１】
更に、前記ゴム輪の樹脂コ−ティング層は、ポリテトラフルオロエチレン５〜１５重量％、アクリル変性ポリエステル２０〜３０重量％および溶剤よりなる主剤１００重量部とポリイソシアネ−ト３５〜４５重量％および溶剤よりなる硬化剤２０重量部を用いて混合した反応液を８０℃で３０分熱硬化するのが最も好ましい。
【００１２】
【発明の実施の形態】
本発明の管受口内面と塩化ビニル管差口外面との間に圧縮介入されるゴム輪を説明すると、図１はゴム輪の斜視図、図２はゴム輪の断面図で、ゴム輪１は、管差口外面に接する面である滑面２に、摩擦係数の低い樹脂コ−ティング層３を有して形成される。該ゴム輪１は、図３に示すように、管継手４の受口５の環状溝６に配置設置され、接続される管、即ち、塩化ビニル管７の差口８を挿入したとき、ゴム輪１の滑面２に備える摩擦係数の低い樹脂コ−ティング層３により容易に挿入され、そして、ゴム輪１は管継手４の受口５の内面と塩化ビニル管７の差口８の外面との間に介在して、塩化ビニル管７の差口８の外面をゴム輪１の滑面２に強固に接続する。
【００１３】
本発明は、ゴム輪１の前記塩化ビニル管７の差口８の外面に接する面である滑面２に、ポリテトラフルオロエチレン３〜２５重量％、アクリル変性ポリエステル５〜６０重量％および溶剤１５〜９２重量％よりなる主剤１００重量部とポリイソシアネ−ト３〜４５重量％および溶剤５５〜９７重量％よりなる硬化剤１０〜３０重量部を混合した反応液を塗布し、室温から１５０℃で１秒〜３０分熱硬化した樹脂コ−ティング層３を設けてなるゴム輪である。
【００１４】
本発明は、ゴム輪１の前記塩化ビニル管７の差口８の外面に接する面である滑面２にポリテトラフルオロエチレン３〜２５重量％、アクリル変性ポリエステル５〜６０重量％および溶剤１５〜９２重量％よりなる主剤１００重量部とポリイソシアネ−ト３〜４５重量％および溶剤５５〜９７重量％よりなる硬化剤１０〜３０重量部を混合した反応液を塗布し、室温から１５０℃で１秒〜３０分熱硬化した樹脂コ−ティング層を設けるゴム輪の製造方法である。
【００１５】
本発明に使用される樹脂コ−テイング層はポリテトラフルオロエチレン、アクリル変性ポリエステルと溶剤よりなる主剤と硬化剤としてポリイソシアネ−トと溶剤よりなるものを熱硬化させたものである。
【００１６】
本発明に使用される主剤の使用量はポリテトラフルオロエチレン５〜１５重量％、アクリル変性ポリエステル２０〜３０重量％、溶剤としてトルエン２５〜３５重量％および酢酸エチル２５〜３５重量％並びにその他の添加剤として、０．１〜１．０重量％を用いるのが好ましい。
本発明に使用される硬化剤の使用量はポリイソシアネ−ト３５〜４５重量％、溶剤としてトルエン５５〜６５重量％を用いるのが好ましい。
そしてこの主剤と硬化剤との混合比（重量比）は１００：２０であるのが好ましい。
本発明の樹脂コ−ティングに使用される溶剤としては、トルエンおよびキシレン等が用いるのが好ましい。
また、本発明に使用される熱硬化方法の条件は、８０℃で３０分であるのが最も好ましい。
【００１７】
本発明のコ−ティングの方法は管継手のゴム輪の滑面に主剤と硬化剤の溶剤に溶解した溶液をスプレ−または刷毛塗りで行なうことができる。
本発明のコ−ティングはゴム継手製造工程の中で安価にかつ容易に滑性塗膜を形成させることが出来現場での作業効率を良くすることができる。
本発明のコ−ティングはゴム輪製造方法の中で安価にできゴム輪への密着性良好で尚且つ耐候性の良い滑性塗膜を形成させることができる。管組み立て現場作業においては作業効率を良くすることができる。
【００１８】
【実施例】
本発明を実施例に基づいて詳細に説明する。なお本発明はこれらの実施例に限定されるものではない。
（実施例）
主剤であるポリテトラフルオロエチレン１０重量％、アクリル変性ポリエステル２９重量％、トルエン３０重量％、酢酸エチル３０重量％、添加剤１重量％および硬化剤であるポリイソシアネ−ト４０重量％、トルエン６０重量％を主剤１００：硬化剤２０の割合で混合した混合液（アクロス株式会社製、ＳＸ２１４ー１６）をスプレ−でゴム輪１の滑面２に塗布する。そして該ゴム輪１を８０℃で３０分熱硬化させる。
ゴム輪１の滑面２にアクリル変性ポリエステルの樹脂コ−ティング層３が作製される。
【００１９】
（比較例１）
主剤であるポリエ−テル化合物、イソシアネ−ト化合物の混合液（坂井化学株式会社製、ＧＬ７１１）、硬化剤および溶剤からなる混合液をゴム輪の滑面に刷毛塗りする。８０℃で３０分熱硬化させる。
【００２０】
（比較例２）
シリコ−ン化合物（東芝シリコ−ン株式会社製、マイクロモノマ−）および硬化剤の混合液をゴム輪の滑面に刷毛塗りする。８０℃で３０分熱硬化させる。
その結果を表１に示す。
【００２１】
【表１】

【００２２】
表１に示すように、本発明のコ−ティング剤の主剤としてアクリル変性ポリエステル系ウレタンを使用した場合、塩化ビニル管７を挿入する挿入荷重は、ユ−ザ−評価が１２ｋｇ、社内評価が４．０ｋｇであるのに対し、ポリエ−テル系ウレタンを主剤とする比較例１では、ユ−ザ−評価が４０ｋｇ、社内評価が６．５ｋｇと大きく、シリコン系を主剤とする比較例２ではユ−ザ−評価が２６ｋｇ、社内評価が５．２ｋｇと大きいものであり、本発明の樹脂コ−ティング層が比較例１及び２と比較して最小の力で挿入することができることが理解できる。しかも、本発明の挿入荷重４．０ｋｇの数値は、滑剤を塗着した場合と同等の挿入荷重が得られ、それ故に、滑剤を補足使用する必要もなく、容易に管を接続することができる。更に摩擦係数の変化は、本発明の樹脂コ−ティング層が初期から１万回まで安定した数値が得られている。
【００２３】
【本発明の効果】
本発明は上記のような構成であるから、管接続に際し、滑剤の塗布を必要とせず、塩化ビニル管の接続に対し非常に容易になし得るゴム輪を提供する。しかもコ−ティング層は特定の樹脂を使用し、該樹脂はゴム輪への密着が良好で製造容易且つ安価に提供し、更には耐候性の良いゴム輪を提供することができる等の効果を奏する。
【図面の簡単な説明】
【図１】本発明にかかるゴム輪である。
【図２】本発明にかかるゴム輪の断面図である。
【図３】本発明のゴム輪を設置した管継手の受口部分と塩化ビニル管の差口の要部断面図である。
【符号の説明】
１ゴム輪
２滑面
３樹脂コ−テイィング層
４管継手
５受口
６環状溝
７塩化ビニル管
８差口[0001]
[Industrial application fields]
The present invention relates to joints of polyvinyl chloride pipes used for water and sewerage or underground line embedment, such as circular vinyl chloride pipes, straight pipes, branched main pipes, egg-type straight pipes of vinyl chloride pipes for sewerage. Rubber rings used for straight pipes with SUS collars and rubber rings for propelling pipes, propelling pipes, joints for rubber ring receiving pipes, flexible bent pipe joints, and V-type universal joints for vinyl chloride pipes for sewers Joints, circular tube manhole joints, egg-shaped manhole joints, for small-diameter drainage masses, for small-diameter public masses, for small-diameter manholes, circular branch pipes, fume pipe branch pipes, ceramic pipe branch pipes, eggs The present invention relates to a rubber ring provided at a joint portion of a vinyl chloride pipe used for a shape branch pipe or the like.
[0002]
[Prior art]
Conventionally, in general, when inserting a tube outlet into a tube receptacle to join the tubes, a watertight rubber ring is interposed between the inner surface of the tube receptacle and the outer surface of the tube receptacle.
The compression intervention of this watertight rubber ring is usually carried out by placing a rubber ring on the inner surface of the pipe inlet in advance and forcibly inserting the pipe outlet into it. In order to compress the rubber ring in the radial direction, a very strong insertion pressure is required for tube insertion. Vinyl chloride pipe manufacturers are struggling with the shape of a rubber ring that allows easy operation when inserting the pipe and has a good water stop effect. As an example, a vinyl chloride tube may receive a very strong insertion load of about 200 kg.
[0003]
For this reason, a lubricant is applied to the outer surface of the pipe opening and the inner surface of the rubber ring from the viewpoint of reducing the frictional resistance during the insertion and preventing the rubber ring from rolling during the insertion. This lubricant is stored in a can container or the like, and in use, the lubricant is taken out of the can container and applied to the surface of the rubber ring that contacts the pipe opening.
[0004]
Also, a rubber ring provided with a resin coating layer having a low friction coefficient on the surface in contact with the outer surface of the pipe opening in order to reduce the frictional resistance during insertion and prevent rolling of the rubber ring during insertion. Is provided. As the resin for the resin coating layer, a resin made of Teflon resin, silicone resin, urethane resin or halogen resin is used.
[0005]
[Problems to be solved by the invention]
Among the methods described in the prior art, the former method of applying the lubricant may be performed at the piping work site even if the insertion load for insertion of the vinyl chloride pipe can be 4.0 kg. Since each rubber ring must be carried out one by one, much time and labor are required for the lubricant application work. Moreover, since the lubricant is generally in the form of a jelly, foreign matter such as sand particles is likely to adhere to the coating surface, and if sand particles or the like adhere to it, this may cause water leakage. In addition, since the application work is an on-site work, it is usually an outdoor work, so the applied lubricant is washed away in the rain or underwater work, and the lubricant is easy to dry under high-temperature dry weather conditions. For this reason, there is a problem that there are many difficult restrictions such as having to perform the connection work quickly. As an example of this, a lubricant is used for a rubber ring of a plug part with a rubber ring at a pipe outlet for a polyvinyl chloride pipe small-diameter drainage mass and public mass, and this plug part is capped at the pipe outlet. In the future, if the pipe is extended and the plug is pulled out and a straight pipe is joined to the pipe outlet using an adhesive, the lubricant remaining on the rubber ring when the plug is capped to the pipe outlet will adversely affect the adhesive. In some cases, sufficient bonding strength cannot be obtained.
[0006]
Furthermore, although the lubricant is considered to be harmless for humans and animals, there is a problem that the lubricant dissolves into the internal fluid when the tube cannot be washed after connecting the pipe, and the internal fluid, for example, tap water, becomes cloudy.
[0007]
In the case of the rubber ring formed with the latter resin coating layer, even if the troublesome work of applying the lubricant to the rubber ring one by one at the work site is unnecessary, the insertion load to the vinyl chloride pipe is Compared with the case where the former lubricant is applied, the insertion work is difficult due to its large size. Therefore, the resin coating layer is used by supplementing the lubricant to the resin coating layer. There was a problem that the smoothed surface could not sufficiently perform the function of reducing the insertion load of the vinyl chloride pipe. Further, the resin coating layer easily discolors the content composition to the vinyl chloride pipe, causing the vinyl chloride pipe to be damaged.
[0008]
The object of the present invention has been made in view of the above-mentioned problems. The purpose of the present invention is to eliminate the need for an on-site lubricant application operation when connecting the pipes of the vinyl chloride pipes. The insertion load is equivalent to the case of using a lubricant applied, so that the pipe connection can be made easily, there is little influence on the vinyl chloride pipe, and a specific resin is used, and it is easy to manufacture at low cost and with a long service life. A long rubber ring is provided.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, a rubber ring provided at a joint portion of a vinyl chloride pipe according to the present invention is a rubber ring that is compressed and interposed between an inner surface of a pipe opening and an outer surface of a vinyl pipe. A resin coating layer using polytetrafluoroethylene, acrylic-modified polyester and polyisocyanate is provided on the surface in contact with the outer surface.
[0010]
The rubber ring has 3 to 25% by weight of polytetrafluoroethylene, 5 to 60% by weight of acryl-modified polyester, and 100 parts by weight of a base material composed of a solvent and a polyisocyanate 3 A resin coating layer obtained by thermally curing a reaction solution mixed with 10 to 30 parts by weight of a curing agent comprising 45% by weight and a solvent at room temperature to 150 ° C. for 1 second to 30 minutes is provided.
[0011]
Further, the resin coating layer of the rubber ring comprises 5 to 15% by weight of polytetrafluoroethylene, 20 to 30% by weight of acryl-modified polyester and 100 parts by weight of a main agent composed of a solvent, 35 to 45% by weight of polyisocyanate and a solvent. Most preferably, the reaction solution mixed using 20 parts by weight of the curing agent is thermally cured at 80 ° C. for 30 minutes.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Referring to a rubber ring that is compressed and interposed between the inner surface of the tube receiving port and the outer surface of the polyvinyl chloride tube outlet, FIG. 1 is a perspective view of the rubber ring, FIG. Is formed by having a resin coating layer 3 having a low friction coefficient on the smooth surface 2 which is a surface in contact with the outer surface of the tube inlet. As shown in FIG. 3, the rubber ring 1 is disposed and installed in the annular groove 6 of the receiving port 5 of the pipe joint 4, and when the pipe to be connected, that is, the outlet 8 of the vinyl chloride pipe 7 is inserted, the rubber ring 1 is The rubber ring 1 is easily inserted by the resin coating layer 3 having a low coefficient of friction provided on the smooth surface 2 of the ring 1, and the rubber ring 1 is connected to the inner surface of the inlet 5 of the pipe joint 4 and the outer surface of the outlet 8 of the vinyl chloride pipe 7. The outer surface of the outlet 8 of the vinyl chloride tube 7 is firmly connected to the smooth surface 2 of the rubber ring 1.
[0013]
In the rubber ring 1, the smooth surface 2, which is a surface in contact with the outer surface of the outlet 8 of the vinyl chloride tube 7, has 3-25% by weight of polytetrafluoroethylene, 5-60% by weight of acrylic-modified polyester, and a solvent 15 A reaction solution in which 100 parts by weight of a main agent composed of ˜92% by weight, 3 to 45% by weight of polyisocyanate and 10 to 30 parts by weight of a curing agent composed of 55 to 97% by weight of a solvent was mixed and applied at room temperature to 150 ° C. This is a rubber ring provided with a resin coating layer 3 which is thermally cured for 2 to 30 minutes.
[0014]
In the present invention, 3 to 25% by weight of polytetrafluoroethylene, 5 to 60% by weight of acrylic-modified polyester, and 15 to 15% of a solvent are applied to the smooth surface 2 which is a surface in contact with the outer surface of the outlet 8 of the vinyl chloride tube 7 of the rubber ring 1 A reaction mixture in which 100 parts by weight of a main agent composed of 92% by weight, 3 to 45% by weight of polyisocyanate and 10 to 30 parts by weight of a curing agent composed of 55 to 97% by weight of a solvent was applied was applied at room temperature to 150 ° C. for 1 second. This is a method for producing a rubber ring provided with a resin coating layer thermally cured for 30 minutes.
[0015]
The resin coating layer used in the present invention is obtained by thermosetting a main component composed of polytetrafluoroethylene, acrylic-modified polyester and a solvent, and a polyisocyanate and a solvent as a curing agent.
[0016]
The amount of the main agent used in the present invention is 5 to 15% by weight of polytetrafluoroethylene, 20 to 30% by weight of acrylic-modified polyester, 25 to 35% by weight of toluene and 25 to 35% by weight of ethyl acetate as a solvent, and other additions It is preferable to use 0.1 to 1.0% by weight as the agent.
The amount of curing agent used in the present invention is preferably 35 to 45% by weight of polyisocyanate and 55 to 65% by weight of toluene as a solvent.
The mixing ratio (weight ratio) between the main agent and the curing agent is preferably 100: 20.
As the solvent used for the resin coating of the present invention, it is preferable to use toluene, xylene and the like.
The conditions of the thermosetting method used in the present invention are most preferably 30 minutes at 80 ° C.
[0017]
The coating method of the present invention can be carried out by spraying or brushing a solution dissolved in the solvent of the main agent and the curing agent on the smooth surface of the rubber ring of the pipe joint.
The coating of the present invention can form a slippery coating film easily and inexpensively in the rubber joint manufacturing process, and can improve the work efficiency in the field.
The coating of the present invention can be made inexpensively in a rubber ring manufacturing method, and can form a slipping coating film having good adhesion to the rubber ring and good weather resistance. The work efficiency can be improved in the pipe assembly site work.
[0018]
【Example】
The present invention will be described in detail based on examples. The present invention is not limited to these examples.
(Example)
10% by weight of polytetrafluoroethylene as a main agent, 29% by weight of acrylic-modified polyester, 30% by weight of toluene, 30% by weight of ethyl acetate, 1% by weight of additive and 40% by weight of polyisocyanate as a curing agent, 60% by weight of toluene A mixed liquid (SX214-16, manufactured by Acros Co., Ltd.) mixed at a ratio of main agent 100: curing agent 20 is applied to the smooth surface 2 of the rubber ring 1 with a spray. The rubber ring 1 is heat-cured at 80 ° C. for 30 minutes.
An acrylic-modified polyester resin coating layer 3 is formed on the smooth surface 2 of the rubber ring 1.
[0019]
(Comparative Example 1)
A liquid mixture comprising a polyether compound and isocyanate compound (GL711, manufactured by Sakai Chemical Co., Ltd.), which is the main agent, and a liquid mixture comprising a curing agent and a solvent are brush-coated on the smooth surface of the rubber ring. Heat cure at 80 ° C. for 30 minutes.
[0020]
(Comparative Example 2)
Brush a mixture of a silicone compound (manufactured by Toshiba Silicon Co., Ltd., micromonomer) and a curing agent onto the smooth surface of the rubber ring. Heat cure at 80 ° C. for 30 minutes.
The results are shown in Table 1.
[0021]
[Table 1]

[0022]
As shown in Table 1, when acrylic modified polyester urethane is used as the main agent of the coating agent of the present invention, the insertion load for inserting the vinyl chloride pipe 7 is 12 kg for user evaluation and 4 for in-house evaluation. Compared to 0.0 kg, in Comparative Example 1 in which polyether urethane is the main agent, the user evaluation is as large as 40 kg, and in-house evaluation is 6.5 kg. -The evaluation is as large as 26 kg and the in-house evaluation is 5.2 kg, and it can be understood that the resin coating layer of the present invention can be inserted with a minimum force as compared with Comparative Examples 1 and 2. Moreover, the numerical value of the insertion load of 4.0 kg according to the present invention provides an insertion load equivalent to that when the lubricant is applied, and therefore it is not necessary to supplement the lubricant and the pipe can be easily connected. . Furthermore, the change in the coefficient of friction is such that the resin coating layer of the present invention has a stable value from the beginning to 10,000 times.
[0023]
[Effect of the present invention]
Since the present invention is configured as described above, it provides a rubber ring that does not require the application of a lubricant when connecting pipes and can be made very easily for connecting vinyl chloride pipes. In addition, the coating layer uses a specific resin, and the resin has good adhesion to the rubber ring, is easy to manufacture and inexpensive, and further can provide a rubber ring with good weather resistance. Play.
[Brief description of the drawings]
1 is a rubber ring according to the present invention.
FIG. 2 is a cross-sectional view of a rubber ring according to the present invention.
FIG. 3 is a cross-sectional view of a principal part of a receiving port portion of a pipe joint provided with a rubber ring of the present invention and a outlet port of a vinyl chloride pipe.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Rubber ring 2 Smooth surface 3 Resin coating layer 4 Pipe joint 5 Receptacle 6 Annular groove 7 Vinyl chloride pipe 8 Outlet

Claims

In a rubber ring that is compressed and interposed between the inner surface of the tube inlet and the outer surface of the polyvinyl chloride tube, polytetrafluoroethylene, acrylic-modified polyester, and polyisocyanate are used on the surface that contacts the outer surface of the polyvinyl chloride tube. A rubber ring provided at a joint portion of a vinyl chloride pipe, characterized by comprising a resin coating layer.

In a rubber ring that is compressed and interposed between the inner surface of the tube inlet and the outer surface of the polyvinyl chloride tube, 3-25% by weight of polytetrafluoroethylene, acrylic modified polyester 5 is provided on the surface in contact with the outer surface of the polyvinyl chloride tube. A reaction mixture prepared by mixing 100 parts by weight of a main agent comprising -60% by weight and 15-92% by weight of a solvent and 10-30 parts by weight of a curing agent comprising 3-45% by weight of polyisocyanate and 55-97% by weight of a solvent. A rubber ring provided at a joint portion of a vinyl chloride pipe, which is provided with a resin coating layer thermally cured at room temperature to 150 ° C. for 1 second to 30 minutes.