JP4742950B2 - Inner coated steel pipe for water piping - Google Patents
Inner coated steel pipe for water piping Download PDFInfo
- Publication number
- JP4742950B2 JP4742950B2 JP2006095723A JP2006095723A JP4742950B2 JP 4742950 B2 JP4742950 B2 JP 4742950B2 JP 2006095723 A JP2006095723 A JP 2006095723A JP 2006095723 A JP2006095723 A JP 2006095723A JP 4742950 B2 JP4742950 B2 JP 4742950B2
- Authority
- JP
- Japan
- Prior art keywords
- steel pipe
- layer
- resin
- treatment
- coated steel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 229910000831 Steel Inorganic materials 0.000 title claims description 72
- 239000010959 steel Substances 0.000 title claims description 72
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims description 36
- 229920005989 resin Polymers 0.000 claims description 29
- 239000011347 resin Substances 0.000 claims description 29
- 229920013716 polyethylene resin Polymers 0.000 claims description 26
- 238000000576 coating method Methods 0.000 claims description 24
- 239000011248 coating agent Substances 0.000 claims description 23
- 238000006243 chemical reaction Methods 0.000 claims description 20
- 239000000843 powder Substances 0.000 claims description 18
- 239000000126 substance Substances 0.000 claims description 18
- 230000008878 coupling Effects 0.000 claims description 14
- 238000010168 coupling process Methods 0.000 claims description 14
- 238000005859 coupling reaction Methods 0.000 claims description 14
- 229910019142 PO4 Inorganic materials 0.000 claims description 12
- 239000010452 phosphate Substances 0.000 claims description 12
- 239000006087 Silane Coupling Agent Substances 0.000 claims description 11
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 claims description 11
- 239000003795 chemical substances by application Substances 0.000 claims description 7
- 238000012986 modification Methods 0.000 claims description 7
- 230000004048 modification Effects 0.000 claims description 7
- 150000001412 amines Chemical class 0.000 claims description 5
- 239000012948 isocyanate Substances 0.000 claims description 5
- 150000002513 isocyanates Chemical class 0.000 claims description 5
- 239000000203 mixture Substances 0.000 claims description 5
- 239000013034 phenoxy resin Substances 0.000 claims description 5
- 229920006287 phenoxy resin Polymers 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 claims description 4
- 239000010410 layer Substances 0.000 description 48
- 239000002345 surface coating layer Substances 0.000 description 16
- -1 polyethylene Polymers 0.000 description 11
- 239000007864 aqueous solution Substances 0.000 description 9
- 238000000034 method Methods 0.000 description 8
- 239000004698 Polyethylene Substances 0.000 description 7
- 229920000573 polyethylene Polymers 0.000 description 7
- 238000005260 corrosion Methods 0.000 description 6
- 239000007788 liquid Substances 0.000 description 6
- BZHJMEDXRYGGRV-UHFFFAOYSA-N Vinyl chloride Chemical compound ClC=C BZHJMEDXRYGGRV-UHFFFAOYSA-N 0.000 description 5
- 239000003822 epoxy resin Substances 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 5
- 229920000647 polyepoxide Polymers 0.000 description 5
- 238000010276 construction Methods 0.000 description 4
- 230000007797 corrosion Effects 0.000 description 4
- 229920000092 linear low density polyethylene Polymers 0.000 description 4
- 239000004707 linear low-density polyethylene Substances 0.000 description 4
- 239000000155 melt Substances 0.000 description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- 239000000853 adhesive Substances 0.000 description 3
- 230000001070 adhesive effect Effects 0.000 description 3
- IQBJFLXHQFMQRP-UHFFFAOYSA-K calcium;zinc;phosphate Chemical compound [Ca+2].[Zn+2].[O-]P([O-])([O-])=O IQBJFLXHQFMQRP-UHFFFAOYSA-K 0.000 description 3
- 239000007822 coupling agent Substances 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- IISBACLAFKSPIT-UHFFFAOYSA-N bisphenol A Chemical compound C=1C=C(O)C=CC=1C(C)(C)C1=CC=C(O)C=C1 IISBACLAFKSPIT-UHFFFAOYSA-N 0.000 description 2
- PXKLMJQFEQBVLD-UHFFFAOYSA-N bisphenol F Chemical compound C1=CC(O)=CC=C1CC1=CC=C(O)C=C1 PXKLMJQFEQBVLD-UHFFFAOYSA-N 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 230000006698 induction Effects 0.000 description 2
- 230000007774 longterm Effects 0.000 description 2
- FPYJFEHAWHCUMM-UHFFFAOYSA-N maleic anhydride Chemical compound O=C1OC(=O)C=C1 FPYJFEHAWHCUMM-UHFFFAOYSA-N 0.000 description 2
- 238000010422 painting Methods 0.000 description 2
- 238000005554 pickling Methods 0.000 description 2
- 238000005507 spraying Methods 0.000 description 2
- 230000037303 wrinkles Effects 0.000 description 2
- LRXTYHSAJDENHV-UHFFFAOYSA-H zinc phosphate Chemical compound [Zn+2].[Zn+2].[Zn+2].[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O LRXTYHSAJDENHV-UHFFFAOYSA-H 0.000 description 2
- 229910000165 zinc phosphate Inorganic materials 0.000 description 2
- ULRCHFVDUCOKTE-UHFFFAOYSA-N 3-[3-aminopropyl(diethoxy)silyl]oxybutan-1-amine Chemical compound NCCC[Si](OCC)(OCC)OC(C)CCN ULRCHFVDUCOKTE-UHFFFAOYSA-N 0.000 description 1
- SJECZPVISLOESU-UHFFFAOYSA-N 3-trimethoxysilylpropan-1-amine Chemical compound CO[Si](OC)(OC)CCCN SJECZPVISLOESU-UHFFFAOYSA-N 0.000 description 1
- PRKPGWQEKNEVEU-UHFFFAOYSA-N 4-methyl-n-(3-triethoxysilylpropyl)pentan-2-imine Chemical compound CCO[Si](OCC)(OCC)CCCN=C(C)CC(C)C PRKPGWQEKNEVEU-UHFFFAOYSA-N 0.000 description 1
- 239000004593 Epoxy Substances 0.000 description 1
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- 239000004696 Poly ether ether ketone Substances 0.000 description 1
- 241000221535 Pucciniales Species 0.000 description 1
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical compound [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 150000008065 acid anhydrides Chemical class 0.000 description 1
- 125000005370 alkoxysilyl group Chemical group 0.000 description 1
- 125000003277 amino group Chemical group 0.000 description 1
- 239000003963 antioxidant agent Substances 0.000 description 1
- 230000003078 antioxidant effect Effects 0.000 description 1
- 238000005422 blasting Methods 0.000 description 1
- 239000001506 calcium phosphate Substances 0.000 description 1
- 229910000389 calcium phosphate Inorganic materials 0.000 description 1
- 235000011010 calcium phosphates Nutrition 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 239000003431 cross linking reagent Substances 0.000 description 1
- 229920003020 cross-linked polyethylene Polymers 0.000 description 1
- 239000004703 cross-linked polyethylene Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- OTARVPUIYXHRRB-UHFFFAOYSA-N diethoxy-methyl-[3-(oxiran-2-ylmethoxy)propyl]silane Chemical compound CCO[Si](C)(OCC)CCCOCC1CO1 OTARVPUIYXHRRB-UHFFFAOYSA-N 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000010828 elution Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 125000003700 epoxy group Chemical group 0.000 description 1
- 229920001903 high density polyethylene Polymers 0.000 description 1
- 239000004700 high-density polyethylene Substances 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 229920001684 low density polyethylene Polymers 0.000 description 1
- 239000004702 low-density polyethylene Substances 0.000 description 1
- 150000003013 phosphoric acid derivatives Chemical class 0.000 description 1
- 239000000049 pigment Substances 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 229920002530 polyetherether ketone Polymers 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 229910000077 silane Inorganic materials 0.000 description 1
- 150000004756 silanes Chemical class 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- 239000008399 tap water Substances 0.000 description 1
- 235000020679 tap water Nutrition 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 229920001187 thermosetting polymer Polymers 0.000 description 1
- QORWJWZARLRLPR-UHFFFAOYSA-H tricalcium bis(phosphate) Chemical compound [Ca+2].[Ca+2].[Ca+2].[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O QORWJWZARLRLPR-UHFFFAOYSA-H 0.000 description 1
- BPSIOYPQMFLKFR-UHFFFAOYSA-N trimethoxy-[3-(oxiran-2-ylmethoxy)propyl]silane Chemical compound CO[Si](OC)(OC)CCCOCC1CO1 BPSIOYPQMFLKFR-UHFFFAOYSA-N 0.000 description 1
Images
Landscapes
- Protection Of Pipes Against Damage, Friction, And Corrosion (AREA)
- Rigid Pipes And Flexible Pipes (AREA)
- Application Of Or Painting With Fluid Materials (AREA)
- Laminated Bodies (AREA)
Description
本発明は、給水管や排水管等のような水配管用の内面被覆鋼管に関する。 The present invention relates to an internally coated steel pipe for water piping such as a water supply pipe and a drain pipe.
従来、給水や排水用等の水配管には、管内面の防食性を付与するために塩化ビニル樹脂を管内面に貼り付けた内面硬質塩ビ被覆鋼管が使用されてきたが、塩化ビニル樹脂は低温での耐衝撃性が低く、寒冷地において水配管用として使用した場合や施工時に屋外放置した場合などに、内面被覆層にダメージを受ける場合がある。さらに、内面硬質塩ビ被覆鋼管は、塩化ビニル樹脂を廃却する際に有害物が発生すること、塩化ビニル樹脂を処理ルートにのせるための鋼管と塩化ビニル樹脂の分離処理の負荷が大きいこと、などの点から、近年では環境負荷が大きい材料という認識をもたれている。 Conventionally, water pipes for water supply and drainage have been used with hard PVC coated steel pipes with vinyl chloride resin affixed to the inner surface of the pipe to provide corrosion resistance to the inner surface of the pipe. The impact resistance is low, and the inner surface coating layer may be damaged when used for water piping in cold districts or when left outdoors during construction. Furthermore, the internal hard PVC coated steel pipe generates harmful substances when the vinyl chloride resin is discarded, and the load of separating the steel pipe and the vinyl chloride resin for placing the vinyl chloride resin on the treatment route is large. In recent years, it has been recognized as a material with a large environmental load.
また、化成処理、プライマー処理等の表面処理が施された鋼管の内面に、加熱した状態でポリエチレン樹脂を粉体塗装することで内面被覆層を形成した内面ポリエチレン被覆鋼管も使用されている（例えば、日本水道協会規格ＪＷＷＡ Ｋ１３２参照）が、この内面ポリエチレン被覆鋼管は、環境によっては管端部での接水により端部から被覆が剥離することがある。
また、プライマー層を有しないものとして、架橋ポリエチレン管に形状復元性を付与し、鋼管内で加熱復元することにより拡径して内面被覆する方法（例えば、特許文献１参照）も知られているが、架橋剤からの溶出成分があるため水道水の衛生性を確保できないなどの問題がある。
In addition, an inner surface polyethylene-coated steel pipe in which an inner surface coating layer is formed by powder coating a polyethylene resin in a heated state on the inner surface of a steel pipe subjected to surface treatment such as chemical conversion treatment or primer treatment is also used (for example, According to Japan Water Works Association Standard JWWA K132), the inner surface polyethylene-coated steel pipe may be peeled off from the end due to water contact at the end of the pipe depending on the environment.
In addition, as a method not having a primer layer, there is also known a method for imparting a shape restoring property to a crosslinked polyethylene pipe and enlarging the diameter by heat restoration in a steel pipe (for example, see Patent Document 1). However, there is a problem that sanitary properties of tap water cannot be ensured due to the elution component from the crosslinking agent.
また、上記のような問題を生じないものとして、ポリエチレン管に形状復元性を付与して鋼管の内面を被覆する方法（例えば、特許文献２参照）も知られているが、この方法では、一旦ポリエチレン等からなる樹脂管を作製し、それに形状復元性などを付加する必要があるため、製造コストが高くなり、また、工業的な速度では均一な内面被覆が困難である。
また、防食性能の高いものとしては、ガス管用等の外面被覆鋼管のための外面被覆材料として様々なものが知られているが、いずれも水配管用内面被覆としては十分な性能を有しない。例えば、フッ素樹脂（例えば、特許文献３参照）、ポリエーテルエーテルケトン樹脂（例えば、特許文献４参照）が知られているが、これらはいずれも樹脂価格が高く、また鋼管に接着しにくいなどの使用上の制約がある。
Further, as a method that does not cause the above problems, there is also known a method (for example, refer to Patent Document 2) in which a polyethylene pipe is given shape recovery and the inner surface of a steel pipe is coated. Since it is necessary to produce a resin tube made of polyethylene or the like and to add shape restoring properties to the resin tube, the manufacturing cost becomes high, and uniform inner surface coating is difficult at an industrial speed.
Moreover, as a thing with high anti-corrosion performance, although various things are known as an outer surface covering material for outer surface covering steel pipes, such as for gas pipes, all do not have sufficient performance as an inner surface covering for water piping. For example, a fluororesin (for example, see Patent Document 3) and a polyether ether ketone resin (for example, see Patent Document 4) are known, but these are both expensive and difficult to adhere to a steel pipe. There are usage restrictions.
給水や排水用等の水配管用として使用される配管は、鋼管と内面被覆層の界面が露出する管端部を防食するために、通常、管端防食継手などを使用して配管されるが、施工不良や長期間の使用によって管端が接水環境に曝されることもあり、このため内面被覆層には、接水環境での耐剥離性（耐水密着性）が求められる。この耐剥離性が低いと、管端が接水環境に曝された時に内面被覆層の剥離が起こり、剥離した部分の鋼管が錆びる結果、赤水などの原因となる。 Pipes used for water pipes for water supply and drainage are usually piped using pipe end anti-corrosion joints to prevent corrosion at the pipe end where the interface between the steel pipe and the inner surface coating layer is exposed. The pipe end may be exposed to a wetted environment due to poor construction or long-term use. For this reason, the inner surface coating layer is required to have peel resistance (waterproof adhesion) in the wetted environment. If this peeling resistance is low, peeling of the inner surface coating layer occurs when the pipe end is exposed to a wetted environment, and the peeled portion of the steel pipe rusts, resulting in red water and the like.
したがって本発明の目的は、このような従来技術の課題を解決し、塩化ビニル樹脂を使用しない内面被覆鋼管であって、内面被覆層が接水環境において優れた耐水密着性（耐剥離性）を有するとともに、耐疵付き性にも優れた水配管用内面被覆鋼管を提供することにある。
また、本発明の他の目的は、特に優れた耐水密着性を示す水配管用内面被覆鋼管の製造方法を提供することにある。
Accordingly, an object of the present invention is to solve such problems of the prior art, and is an inner surface coated steel pipe that does not use a vinyl chloride resin, and the inner surface coating layer has excellent water resistance adhesion (peeling resistance) in a wetted environment. Another object of the present invention is to provide an inner surface-coated steel pipe for water piping that has excellent weather resistance.
Another object of the present invention is to provide a method for producing an internally coated steel pipe for water piping that exhibits particularly excellent water-resistant adhesion.
本発明者らは、高い耐水密着性（耐剥離性）と耐疵付き性を有する内面被覆層について鋭意研究した結果、鋼管内面に下層側から順に、リン酸塩化成処理層、シラン系カップリング処理層、プライマー層および変性ポリエチレン系樹脂層を形成することにより、内面被覆層が優れた耐水密着性と耐疵付き性を有する内面被覆鋼管が得られることが判った。また、変性ポリエチレン系樹脂層を特定の加熱条件の粉体塗装で形成することにより、特に優れた耐水密着性が得られることも判った。 As a result of earnest research on the inner surface coating layer having high water-resistant adhesion (peeling resistance) and scratch resistance, the present inventors, in order from the lower layer side to the inner surface of the steel pipe, phosphatization treatment layer, silane coupling It was found that by forming the treatment layer, the primer layer, and the modified polyethylene resin layer, an inner surface-coated steel pipe having an excellent inner surface coating layer having excellent water resistance adhesion and wrinkle resistance can be obtained. It was also found that particularly excellent water-resistant adhesion can be obtained by forming the modified polyethylene resin layer by powder coating under specific heating conditions.
本発明はこのような知見に基づきなされたもので、その要旨は以下のとおりである。
［1］鋼管の内面に、鋼管面側から順に、リン酸塩化成処理層、シラン系カップリング剤によるカップリング処理層、アミン系またはイソシアネート系硬化剤とフェノキシ樹脂との混合物により形成されたプライマー層、変性ポリエチレン系樹脂を主成分とする樹脂層を形成したことを特徴とする水配管用内面被覆鋼管。
［2］内面にリン酸塩化成処理、シラン系カップリング剤によるカップリング処理およびアミン系またはイソシアネート系硬化剤とフェノキシ樹脂との混合物によるプライマー処理が順に施された鋼管を２１０℃以上に加熱した状態で、鋼管内面に変性ポリエチレン系樹脂を主成分とする粉体塗料による粉体塗装を行い、引き続き２００℃以上で４分以上保熱することにより変性ポリエチレン系樹脂を主成分とする樹脂層を形成させることを特徴とする水配管用内面被覆鋼管の製造方法。
The present invention has been made based on such findings, and the gist thereof is as follows.
[1] A primer formed on the inner surface of a steel pipe in order from the steel pipe surface side by a phosphate chemical conversion treatment layer, a coupling treatment layer with a silane coupling agent , a mixture of an amine or isocyanate curing agent and a phenoxy resin. An inner surface-coated steel pipe for water piping, characterized in that a layer and a resin layer mainly composed of a modified polyethylene resin are formed.
[2] A steel pipe whose inner surface was sequentially subjected to a phosphate conversion treatment, a coupling treatment with a silane coupling agent , and a primer treatment with a mixture of an amine or isocyanate curing agent and a phenoxy resin was heated to 210 ° C. or higher. In this state, the inner surface of the steel pipe is powder-coated with a powder coating mainly composed of a modified polyethylene resin, and subsequently heat-retained at 200 ° C. or more for 4 minutes or more to form a resin layer mainly composed of the modified polyethylene resin. A method for producing an inner surface-coated steel pipe for water piping, characterized by comprising:
本発明の内面被覆鋼管は、従来の内面ポリエチレン被覆鋼管に較べて内面被覆層の耐水密着性が高く、施工不良や長期使用などにより管端部が接水環境に曝された時でも、高い耐久性を示す。 The inner surface-coated steel pipe of the present invention has higher water-resistant adhesion of the inner surface coating layer than conventional inner surface polyethylene-coated steel pipe, and has high durability even when the end of the pipe is exposed to a wetted environment due to poor construction or long-term use. Showing gender.
本発明は、鋼管内面に、鋼管面側から順に、リン酸塩化成処理層、シラン系カップリング剤によるカップリング処理層、プライマー層、変性ポリエチレン系樹脂を主成分とする樹脂層を形成した水配管用内面被覆鋼管である。
図１は、本発明の内面被覆鋼管の断面を模式的に示すものであり、１は鋼管、２はリン酸塩化成処理層、３はカップリング処理層、４はプライマー層、５は変性ポリエチレン系樹脂を主成分とする樹脂層である。
The present invention is a water in which a phosphate chemical conversion treatment layer, a coupling treatment layer with a silane coupling agent, a primer layer, and a resin layer mainly composed of a modified polyethylene resin are formed on the inner surface of the steel pipe in order from the steel pipe surface side. This is an internally coated steel pipe for piping.
FIG. 1 schematically shows a cross section of an inner surface-coated steel pipe according to the present invention, wherein 1 is a steel pipe, 2 is a phosphate conversion treatment layer, 3 is a coupling treatment layer, 4 is a primer layer, and 5 is a modified polyethylene. This is a resin layer mainly composed of a resin.
前記鋼管１は、管外面にブラスト処理、酸洗処理、化成処理、メッキ処理、プライマー処理もしくは樹脂被覆等の１つ以上を行なったものでもよい。また、通常は管内面にブラスト処理及び酸洗処理等がなされ、その後の化成処理等が行いやすいようにする。鋼管１のサイズに特に制限はないが、一般には外径１０〜１７０ｍｍ程度、長さ４〜６ｍ程度、肉厚２．０〜５．３ｍｍ程度のものを用いる。
前記リン酸塩化成処理層２は、リン酸亜鉛、リン酸カルシウム等のリン酸塩系の化成処理を単独又は併用した処理を行うことで形成することができる。このリン酸塩化成処理では、化成処理液を鋼管内面に吹き付け若しくは流し込む方法、化成処理液の浴に鋼管を浸漬する方法などが採られる。化成処理液には反応促進のための促進剤等を添加してもよく、また、液を６０℃以上に加温した状態で処理してもよい。
The steel pipe 1 may be one in which one or more of blast treatment, pickling treatment, chemical conversion treatment, plating treatment, primer treatment, resin coating and the like are performed on the outer surface of the pipe. Further, blasting and pickling are usually performed on the inner surface of the pipe so that the subsequent chemical conversion treatment can be easily performed. Although there is no restriction | limiting in particular in the size of the steel pipe 1, Generally, an outer diameter of about 10-170 mm, a length of about 4-6 m, and a wall thickness of about 2.0-5.3 mm are used.
The phosphate chemical conversion treatment layer 2 can be formed by performing a treatment using a phosphate chemical conversion treatment such as zinc phosphate and calcium phosphate alone or in combination. In this phosphate chemical conversion treatment, a method of spraying or pouring the chemical conversion treatment liquid onto the inner surface of the steel pipe, a method of immersing the steel pipe in a bath of the chemical conversion treatment liquid, and the like are employed. An accelerator for promoting the reaction may be added to the chemical conversion treatment liquid, or the liquid may be treated in a state of being heated to 60 ° C. or higher.
前記カップリング処理層３は、上記リン酸亜鉛化成処理を行なった後に行なうシラン系カップリング剤によるカップリング処理に形成される。
このカップリング処理では、通常、シラン系カップリング剤濃度が０．１〜３mass％程度の水溶液、或いはアルコールや酢酸などを加えた水溶液に有機系シラン系カップリング剤を０．１〜３mass％程度の濃度で添加したものが使用される。有機系シラン系カップリング剤の濃度が０．１mass％未満では、耐水密着性の向上効果が小さい。
このような水溶液をリン酸塩化成処理を施した鋼管内面に塗布して１００℃以上に加熱乾燥することで、カップリング処理を行うことができる。
The coupling treatment layer 3 is formed by a coupling treatment with a silane coupling agent performed after the zinc phosphate chemical conversion treatment.
In this coupling treatment, an organic silane coupling agent is usually added to an aqueous solution having a silane coupling agent concentration of about 0.1 to 3 mass%, or an aqueous solution in which alcohol, acetic acid, or the like is added to about 0.1 to 3 mass%. The one added at the concentration is used. When the concentration of the organic silane coupling agent is less than 0.1 mass%, the effect of improving water-resistant adhesion is small.
A coupling treatment can be performed by applying such an aqueous solution to the inner surface of a steel pipe that has been subjected to a phosphate chemical conversion treatment, and drying by heating to 100 ° C. or higher.
シラン系カップリング剤は、分子の片端にアルコキシシリル基を有し、他の片端にエポキシ基、アミノ基などを有する化合物であり、例えば、γ−グリシドキシプロピルトリメトキシシラン、β−(３，４−エポキシシクロヘキシル)エチルトリメトキシラン、γ−グリシドキシプロピルメチルジエトキシシラン等のエポキシ系シラン化合物、３−アミノプロピルトリメトキシラン、３−アミノプロピルトリエトキシラン、Ν−２(アミノエチル)３−アミノプロピルトリメトキシシラン、Ν−２(アミノエチル)３−アミノプロピルトリエトキシシラン、３−トリエトキシシリル−Ｎ−(１，３−ジメチル−ブチリデン)プロピルアミン等のアミノ系シラン化合物が挙げられる。 Silane coupling agents are compounds having an alkoxysilyl group at one end of the molecule and an epoxy group, amino group, etc. at the other end, such as γ-glycidoxypropyltrimethoxysilane, β- (3 , 4-epoxycyclohexyl) ethyltrimethoxylane, epoxy-based silane compounds such as γ-glycidoxypropylmethyldiethoxysilane, 3-aminopropyltrimethoxylane, 3-aminopropyltriethoxylane, Ν-2 (aminoethyl) Amino silane compounds such as 3-aminopropyltrimethoxysilane, Ν-2 (aminoethyl) 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine Can be mentioned.
前記プライマー層４に用いる樹脂は特に限定しないが、例えば、(1)ビスフェノールＡ型またはビスフェノールＦ型のエポキシ樹脂を主剤とし、ジシアンジアミド系化合物またはアミン系化合物を硬化剤とする１液型若しくは２液型の熱硬化性エポキシ樹脂、(2)アミン系またはイソシアネート系などの硬化剤とフェノキシ樹脂との混合物、(3)予め硬化剤と混合してある粉体エポキシ樹脂、などを使用することができる。また、エポキシ樹脂を用いる場合には、耐水密着性の観点から分子量が１６００以上のものが特に好ましい。
The resin used for the
粉体プライマーを用いる場合には、通常、１００〜２５０℃程度に加熱した鋼管の内面に粉体塗装を行う。また、液状プライマーを用いる場合には、鋼管内面にスプレー塗装などの方法で塗装することができる。この場合、塗装前に鋼管を加熱してもよく、また、塗装後に鋼管を熱風や高周波誘導加熱などの方法で加熱してもよい。
プライマー処理では、通常、乾燥後または硬化後のプライマー層の厚みが、液状プライマーの場合には５〜１００μｍ程度、粉体プライマーの場合には２００〜５００μｍ程度になるように、それぞれ塗装を行う。プライマー層の厚みが上記よりも薄いと、ピンホール等の発生により下地を均一に覆うことができなくなり、被覆の防食性能が低下する。また、プライマー層の厚みが上記よりも厚くなると、層厚に見合った被覆の防食性の向上が期待できず、また、粉体塗装の塗装時間が長くなり、生産性が低下する。
When a powder primer is used, powder coating is usually performed on the inner surface of a steel pipe heated to about 100 to 250 ° C. Moreover, when using a liquid primer, it can coat by methods, such as spray coating, to the steel pipe inner surface. In this case, the steel pipe may be heated before painting, or the steel pipe may be heated by hot air or high-frequency induction heating after painting.
In the primer treatment, coating is usually performed so that the thickness of the primer layer after drying or curing is about 5 to 100 μm in the case of a liquid primer and about 200 to 500 μm in the case of a powder primer. If the thickness of the primer layer is thinner than the above, the base cannot be uniformly covered due to the occurrence of pinholes and the like, and the anticorrosion performance of the coating is lowered. On the other hand, when the thickness of the primer layer is larger than the above, it is not possible to expect an improvement in the corrosion resistance of the coating corresponding to the layer thickness, and the coating time of the powder coating becomes longer and the productivity is lowered.
前記変性ポリエチレン系樹脂を主成分とする樹脂層５に用いられる変性ポリエチレン樹脂は公知の樹脂でよく、例えば、直鎖状低密度ポリエチレン、高圧法低密度ポリエチレン、高密度ポリエチレン等のポリエチレンを無水マレイン酸等の酸無水物によりグラフト変性したものが挙げられる。この変性ポリエチレン系樹脂は、通常、変性量が６mass％以下で定法により変性して得られるものである。また、通常、メルトインデックスが２以上８以下のものが用いられる。
また、上記変性ポリエチレン系樹脂には、樹脂層５の性能を損なわない範囲で他の樹脂を混合してもよく、また、必要に応じて酸化防止剤や顔料などを添加してもよい。
The modified polyethylene resin used for the
In addition, other resins may be mixed with the modified polyethylene resin as long as the performance of the
変性ポリエチレン系樹脂を主成分とする樹脂層５の層厚は特に限定しないが、一般には０．３〜１．０ｍｍ程度、特に好ましくは０．５〜０．９ｍｍ程度とすることが好ましい。層厚が上記よりも薄いと施工時の疵付きなどで樹脂層に穴があき、透水性の高いプライマー層（エポキシ樹脂層など）がむき出しになるため、防食性が損なわれる恐れがある。また、層厚が上記よりも厚いと粉体塗装の塗装時間が長くなり、生産性が低下する。
The layer thickness of the
変性ポリエチレン系樹脂を主成分とする樹脂層５は、粉体塗装で形成することが望ましい。これは、他の塗装方法では上記のような薄膜の樹脂層とすることが困難だからである。
また、この粉体塗装に当たっては、内面にリン酸塩化成処理、シラン系カップリング剤によるカップリング処理およびプライマー処理が順に施された鋼管１を２１０℃以上に加熱した状態で、変性ポリエチレン系樹脂を主成分とする粉体塗料による粉体塗装を行い、引き続き２００℃以上で４分以上保熱して変性ポリエチレン系樹脂を主成分とする樹脂層を形成させることが好ましく、これにより特に優れた耐水密着性を有する変性ポリエチレン系樹脂を主成分とする樹脂層５を得ることができる。加熱温度が上記温度未満では、樹脂層にピンホール等の欠陥が発生しやすくなる。
The
In addition, in this powder coating, the modified polyethylene resin in a state where the steel pipe 1 whose inner surface is subjected to the phosphate chemical conversion treatment, the coupling treatment with the silane coupling agent and the primer treatment in this order is heated to 210 ° C. or higher. It is preferable to form a resin layer mainly composed of a modified polyethylene resin by performing powder coating with a powder coating material mainly composed of water and subsequently heat-incubating at 200 ° C. or higher for 4 minutes or longer. A
［発明例１及び参考例１〜５］
酸洗処理した鋼管（内径２７．６ｍｍφ，外径３４ｍｍφ×４ｍ）を８０℃のリン酸亜鉛カルシウム系処理液に浸漬後、エアブローし、さらに湯洗した後、再度エアブローした。得られた鋼管の内面に表１に記載のカップリング剤水溶液を塗布した。管内面に付着している水溶液をエアブローで絞った後、熱風炉内で鋼管を１１０℃に加熱した。鋼管を５０℃以下にさましてから、溶剤希釈した表１に記載のプライマーを塗布し、２１５℃に加熱した。この加熱した鋼管内面に密度０．９２３、メルトインデックス６．３の直鎖状低密度ポリエチレンを無水マレイン酸変性した粉状の変性ポリエチレン樹脂を粉体塗装し、厚さ０．６〜０．８ｍｍの変性ポリエチレン樹脂層を得た。塗装後、２００℃の炉内で４分保持した後、自然冷却して内面被覆鋼管を得た。
[Invention Example 1 and Reference Examples 1 to 5 ]
The pickled steel pipe (inner diameter: 27.6 mmφ, outer diameter: 34 mmφ × 4 m) was immersed in an 80 ° C. zinc calcium phosphate treatment solution, then blown with air, further rinsed with hot water, and then again blown with air. A coupling agent aqueous solution described in Table 1 was applied to the inner surface of the obtained steel pipe. After the aqueous solution adhering to the inner surface of the tube was squeezed by air blow, the steel tube was heated to 110 ° C. in a hot air furnace. After the steel pipe was cooled to 50 ° C. or lower, the solvent-diluted primer shown in Table 1 was applied and heated to 215 ° C. Powdered modified polyethylene resin obtained by maleic anhydride modification of linear low density polyethylene having a density of 0.923 and a melt index of 6.3 is coated on the inner surface of the heated steel pipe to a thickness of 0.6 to 0.8 mm. The modified polyethylene resin layer was obtained. After coating, it was kept in a furnace at 200 ° C. for 4 minutes, and then naturally cooled to obtain an inner surface coated steel pipe.
［参考例６〜８］
酸洗処理した鋼管（内径２７．６ｍｍφ，外径３４ｍｍφ×４ｍ）を８０℃のリン酸亜鉛カルシウム系処理液に浸漬後、エアブローし、さらに湯洗した後、再度エアブローした。得られた鋼管の内面に、表１に記載のカップリング剤水溶液を塗布した。管内面に付着している水溶液をエアブローで絞った後、高周波誘導加熱で鋼管を２２０℃に加熱した。加熱した鋼管に表１に記載の粉体プライマーを粉体塗装し、さらに、鋼管内面に密度０．９３７、メルトインデックス４．０の直鎖状低密度ポリエチレンを無水マレイン酸変性した粉状の変性ポリエチレン樹脂を粉体塗装し、厚さ０．６〜０．８ｍｍの変性ポリエチレン樹脂層を得た。塗装後、２００℃の炉内で４分保持した後、自然冷却して内面被覆鋼管を得た。
[ Reference Examples 6 to 8 ]
The pickled steel pipe (inner diameter: 27.6 mmφ, outer diameter: 34 mmφ × 4 m) was immersed in an 80 ° C. zinc calcium phosphate treatment solution, then blown with air, further rinsed with hot water, and then again blown with air. A coupling agent aqueous solution described in Table 1 was applied to the inner surface of the obtained steel pipe. After the aqueous solution adhering to the inner surface of the tube was squeezed by air blow, the steel tube was heated to 220 ° C. by high frequency induction heating. Powdered modification obtained by coating a heated steel pipe with the powder primer described in Table 1 and further modifying the inner surface of the pipe with maleic anhydride-modified linear low density polyethylene having a density of 0.937 and a melt index of 4.0 Polyethylene resin was powder-coated to obtain a modified polyethylene resin layer having a thickness of 0.6 to 0.8 mm. After coating, it was kept in a furnace at 200 ° C. for 4 minutes, and then naturally cooled to obtain an inner surface coated steel pipe.
［参考例９］
酸洗処理した鋼管（内径２７．６ｍｍφ，外径３４ｍｍφ×４ｍ）を８０℃のリン酸亜鉛カルシウム系処理液に浸漬後、エアブローし、さらに湯洗した後、再度エアブローした。得られた鋼管の内面に、表１に記載のカップリング剤水溶液を塗布した。管内面に付着している水溶液をエアブローで絞った後、熱風炉内で鋼管を１１０℃に加熱した。鋼管を５０℃以下にさましてから、溶剤希釈した表１のプライマーを塗布し２１５℃に加熱した。この加熱した鋼管内面に密度０．９２３、メルトインデックス６．３の直鎖状低密度ポリエチレンを無水マレイン酸変性した粉状の変性ポリエチレン樹脂を粉体塗装し、厚さ０．６〜０．８ｍｍの変性ポリエチレン樹脂層を得た。塗装後、２００℃の炉内で３分保持した後、自然冷却して内面被覆鋼管を得た。
［比較例１〜５］
カップリング処理を行わなかった以外は発明例１と同様にして、表２に記載のプライマーを用いて内面被覆鋼管を得た。
[ Reference Example 9 ]
The pickled steel pipe (inner diameter: 27.6 mmφ, outer diameter: 34 mmφ × 4 m) was immersed in an 80 ° C. zinc calcium phosphate treatment solution, then blown with air, further rinsed with hot water, and then again blown with air. A coupling agent aqueous solution described in Table 1 was applied to the inner surface of the obtained steel pipe. After the aqueous solution adhering to the inner surface of the tube was squeezed by air blow, the steel tube was heated to 110 ° C. in a hot air furnace. After cooling the steel pipe to 50 ° C. or lower, the primer of Table 1 diluted with a solvent was applied and heated to 215 ° C. Powdered modified polyethylene resin obtained by maleic anhydride modification of linear low density polyethylene having a density of 0.923 and a melt index of 6.3 is coated on the inner surface of the heated steel pipe to a thickness of 0.6 to 0.8 mm. The modified polyethylene resin layer was obtained. After coating, it was kept in a furnace at 200 ° C. for 3 minutes, and then naturally cooled to obtain an internally coated steel pipe.
[Comparative Examples 1-5]
An internally coated steel pipe was obtained using the primers shown in Table 2 in the same manner as in Invention Example 1 except that the coupling treatment was not performed.
以上のようにして得られた各実施例の被覆鋼管について、内面被覆層の耐水密着性（耐剥離性）を以下のようにして評価した。
内面被覆鋼管を５０ｃｍ長さに切断し、内面に７０℃の熱水と室温の水を１０分ずつ交互に流した。このサイクルを１７０００回繰り返した後、鋼管端部の内面被覆層の剥離状況を観察するとともに、９０°ピール試験により内面被覆層の接着力を測定し、下記により評価した。
×：鋼管端部の内面被覆層の剥離がある。
○：内面被覆層の接着力が３ｋｇｆ／ｃｍ未満であるが、内面被覆層の剥離はない。
◎：内面被覆層の接着力が３ｋｇｆ／ｃｍ以上
About the coated steel pipe of each Example obtained as mentioned above, the water-resistant adhesion (peeling resistance) of the inner surface coating layer was evaluated as follows.
The inner surface-coated steel pipe was cut to a length of 50 cm, and 70 ° C. hot water and room temperature water were alternately flowed to the inner surface for 10 minutes each. After repeating this cycle 17000 times, the peeling state of the inner surface coating layer at the end of the steel pipe was observed, and the adhesive strength of the inner surface coating layer was measured by a 90 ° peel test, and evaluated as follows.
X: There exists peeling of the inner surface coating layer of a steel pipe edge part.
○: The adhesive force of the inner surface coating layer is less than 3 kgf / cm, but there is no peeling of the inner surface coating layer.
A: Adhesive strength of the inner surface coating layer is 3 kgf / cm or more
１ 鋼管
２ リン酸塩化成処理層
３ カップリング処理層
４ プライマー層
５ 変性ポリエチレン系樹脂を主成分とする樹脂層
DESCRIPTION OF SYMBOLS 1 Steel pipe 2 Phosphate chemical conversion treatment layer 3
Claims (2)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2006095723A JP4742950B2 (en) | 2006-03-30 | 2006-03-30 | Inner coated steel pipe for water piping |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2006095723A JP4742950B2 (en) | 2006-03-30 | 2006-03-30 | Inner coated steel pipe for water piping |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2007268797A JP2007268797A (en) | 2007-10-18 |
| JP4742950B2 true JP4742950B2 (en) | 2011-08-10 |
Family
ID=38672100
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2006095723A Active JP4742950B2 (en) | 2006-03-30 | 2006-03-30 | Inner coated steel pipe for water piping |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4742950B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009072768A (en) * | 2007-08-31 | 2009-04-09 | Jfe Steel Kk | Method for manufacturing internal coated steel pipe |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5353297B2 (en) * | 2009-02-25 | 2013-11-27 | Ｊｆｅスチール株式会社 | Polyolefin powder lining steel pipe |
| JP5648525B2 (en) * | 2010-03-25 | 2015-01-07 | Ｊｆｅスチール株式会社 | Inner coated steel pipe for water piping |
| JP5644546B2 (en) * | 2011-01-27 | 2014-12-24 | Ｊｆｅスチール株式会社 | Manufacturing method of inner surface coated steel pipe for water piping |
| KR101655931B1 (en) * | 2015-09-24 | 2016-09-08 | 주식회사 투에이취켐 | Hybrid powder coating material |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS50139831A (en) * | 1974-04-27 | 1975-11-08 | ||
| JPS5280239A (en) * | 1975-12-27 | 1977-07-05 | Nippon Steel Corp | Finishing process for phosphate coating |
| JPS52117843A (en) * | 1976-03-30 | 1977-10-03 | Sumitomo Metal Ind | Method of fabricating steel pipe having coated internal surface |
| JPS5328636A (en) * | 1976-08-30 | 1978-03-17 | Nippon Kokan Kk <Nkk> | Manufacture of steel pipes covered with polyethylene resin inside |
| JPS5340025A (en) * | 1976-09-24 | 1978-04-12 | Nippon Paint Co Ltd | Coating material for water pepe |
| JPS5440837A (en) * | 1977-09-06 | 1979-03-31 | Nippon Steel Corp | Manufacturing of steel pipe having resin-lined inner surface |
| JPS54132631A (en) * | 1978-04-07 | 1979-10-15 | Mitsui Petrochem Ind Ltd | Powdered coating composition |
| JPS5665667A (en) * | 1979-10-31 | 1981-06-03 | Mitsubishi Petrochem Co Ltd | Preparation of crosslinked polyolefin coated steel pipe |
| JPS56101825A (en) * | 1980-01-18 | 1981-08-14 | Nippon Steel Corp | Manufacture of steel pipe covered with polyolefin |
| JPS6176684A (en) * | 1984-09-21 | 1986-04-19 | Sumitomo Metal Ind Ltd | Corrosion-proof coated steel material having superior secondary adhesion at edge |
-
2006
- 2006-03-30 JP JP2006095723A patent/JP4742950B2/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS50139831A (en) * | 1974-04-27 | 1975-11-08 | ||
| JPS5280239A (en) * | 1975-12-27 | 1977-07-05 | Nippon Steel Corp | Finishing process for phosphate coating |
| JPS52117843A (en) * | 1976-03-30 | 1977-10-03 | Sumitomo Metal Ind | Method of fabricating steel pipe having coated internal surface |
| JPS5328636A (en) * | 1976-08-30 | 1978-03-17 | Nippon Kokan Kk <Nkk> | Manufacture of steel pipes covered with polyethylene resin inside |
| JPS5340025A (en) * | 1976-09-24 | 1978-04-12 | Nippon Paint Co Ltd | Coating material for water pepe |
| JPS5440837A (en) * | 1977-09-06 | 1979-03-31 | Nippon Steel Corp | Manufacturing of steel pipe having resin-lined inner surface |
| JPS54132631A (en) * | 1978-04-07 | 1979-10-15 | Mitsui Petrochem Ind Ltd | Powdered coating composition |
| JPS5665667A (en) * | 1979-10-31 | 1981-06-03 | Mitsubishi Petrochem Co Ltd | Preparation of crosslinked polyolefin coated steel pipe |
| JPS56101825A (en) * | 1980-01-18 | 1981-08-14 | Nippon Steel Corp | Manufacture of steel pipe covered with polyolefin |
| JPS6176684A (en) * | 1984-09-21 | 1986-04-19 | Sumitomo Metal Ind Ltd | Corrosion-proof coated steel material having superior secondary adhesion at edge |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009072768A (en) * | 2007-08-31 | 2009-04-09 | Jfe Steel Kk | Method for manufacturing internal coated steel pipe |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2007268797A (en) | 2007-10-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4742950B2 (en) | Inner coated steel pipe for water piping | |
| TW201219598A (en) | Method for manufacturing zinc coated steel sheet and the zinc coated steel sheet | |
| JP5353297B2 (en) | Polyolefin powder lining steel pipe | |
| JPS59222275A (en) | Coating method of metallic surface | |
| JP2003293160A (en) | Polyolefin-coated steel | |
| JP5233493B2 (en) | Manufacturing method of inner surface coated steel pipe | |
| JP4742949B2 (en) | Inner coated steel pipe for water piping | |
| JP6079717B2 (en) | Polyethylene-coated steel pipe and manufacturing method thereof | |
| JP2000190422A (en) | Polyolefin-coated steel material | |
| JP6085932B2 (en) | Polyethylene-coated steel material and epoxy resin primer layer forming material | |
| JP6398851B2 (en) | Polyolefin-coated steel with base conversion treatment | |
| JP5471127B2 (en) | Inner coated steel pipe for water piping | |
| JP5463999B2 (en) | Manufacturing method of inner surface coated steel pipe for water piping | |
| JP5359098B2 (en) | Inner coated steel pipe for water piping | |
| JP2018193570A (en) | Manufacturing method of coated steel tube | |
| JP4207632B2 (en) | Polyolefin coated steel | |
| JPH1028928A (en) | Polyolefin coated steel material | |
| JP6583012B2 (en) | Polyolefin-coated steel pipe and method for producing the same | |
| JPH10264308A (en) | Polyolefin-coated steel pipe and its manufacture | |
| JPH03104634A (en) | Production of steel pipe having outer face coated with plastic | |
| JPH08156181A (en) | Polyolefin resin-coated steel pipe and production thereof | |
| JP5648525B2 (en) | Inner coated steel pipe for water piping | |
| JP6623543B2 (en) | Organic resin coated steel | |
| JPH11141054A (en) | Covered steel wire excellent in corrosion resistance | |
| JPS6097075A (en) | Preparation of double layer coated steel pipe |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20090213 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20110120 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20110201 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20110317 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20110412 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20110425 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20140520 Year of fee payment: 3 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 4742950 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |