JP3113719B2 - Method of forming synthetic hemimorphite corrosion resistant film - Google Patents
Method of forming synthetic hemimorphite corrosion resistant filmInfo
- Publication number
- JP3113719B2 JP3113719B2 JP04007851A JP785192A JP3113719B2 JP 3113719 B2 JP3113719 B2 JP 3113719B2 JP 04007851 A JP04007851 A JP 04007851A JP 785192 A JP785192 A JP 785192A JP 3113719 B2 JP3113719 B2 JP 3113719B2
- Authority
- JP
- Japan
- Prior art keywords
- hemimorphite
- zinc
- water
- silicon
- corrosion
- 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.)
- Expired - Fee Related
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- Application Of Or Painting With Fluid Materials (AREA)
- Silicon Compounds (AREA)
- Chemically Coating (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は、水道管、下水道管等給
水または排水を目的とする配管、温水器の配管、給湯
管、冷暖房用冷温水系の循環配管、給湯設備の貯水タン
ク等、貯水設備あるいは配管の内面への合成ヘミモルフ
ァイト耐食皮膜の形成方法及び自動車鋼板や屋根材等の
外装鋼板表面への合成ヘミモルファイト耐食皮膜の形成
方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to water pipes such as water pipes and sewer pipes for water supply or drainage, water heater pipes, hot water pipes, circulating pipes for cooling / heating water systems for cooling and heating, and water storage tanks for hot water supply equipment. The present invention relates to a method for forming a synthetic hemimorphite corrosion-resistant coating on the inner surface of equipment or piping and a method for forming a synthetic hemimorphite corrosion-resistant coating on the surface of exterior steel plates such as automobile steel plates and roofing materials.
【０００２】[0002]
【従来の技術】従来、自動車鋼板の下地や橋梁等の防食
塗料として、特開昭５９−２１２２５６号公報、特公昭
５３−３７２５５号公報等に記載の亜鉛粉末と有機系或
いは無機系の珪酸塩を主体としたジンクリッチペイント
が使用されてきた。この塗膜は鋼板等の材料の表面に塗
布するだけで、特に加熱処理等をして皮膜を安定な化合
物にすることなく、塗布乾燥後そのまま防食皮膜として
使用される。2. Description of the Related Art Conventionally, zinc powder and organic or inorganic silicates described in JP-A-59-212256 and JP-B-53-37255 have been used as anticorrosion paints for foundations of automobile steel plates and bridges. Zinc rich paint has been used. This coating film is used as an anticorrosion film after coating and drying, without being applied only to the surface of a material such as a steel sheet, in particular, without heat treatment or the like to convert the film into a stable compound.
【０００３】一方、特開昭６２−３７３７８号公報に
は、金属アルコキシドに水やアルコールを加えて、母材
表面に塗布し、加熱して、母材表面にガラス質の皮膜を
形成し、基材の耐食性を向上させることも開示されてい
る。On the other hand, Japanese Patent Application Laid-Open No. 62-37378 discloses that a metal alkoxide is added to water or alcohol, applied to the surface of a base material and heated to form a glassy film on the surface of the base material. It is also disclosed to improve the corrosion resistance of the material.
【０００４】しかしながら、近年の大都市における水源
汚染に伴う上水系、下水系の水質が複雑に変化してお
り、これによる配管の腐食形態も複雑になってきてお
り、上記従来提案された耐食性改善の手段を以てしても
長年の使用に耐えられなくなってきている。However, the water quality of the water supply system and the sewage system has been complicatedly changed due to the recent pollution of water sources in large cities, and the corrosive form of the piping has also become complicated. However, it has become impossible to withstand years of use.
【０００５】本願の発明者は、かかる上水道配管の腐食
機構についての研究報告を１９８９年、「腐食防食 '
８９」に発表した。この報告は亜鉛の腐食生成物として
ヘミモルファイトの腐食配管断面での分布についても言
及している。The inventor of the present application reported a research report on such a corrosion mechanism of water supply piping in 1989, "Corrosion Protection".
89 ". The report also mentions the distribution of hemimorphite as a corrosion product of zinc in the cross section of corroded piping.
【０００６】その中で、腐食機構において注目すべき現
象として、腐食水道管内面の局部的に腐食した錆こぶと
称する部分以外の均一腐食部分には、ヘミモルファイト
が多く存在し、この層の下部には腐食が発生していない
としている。Among them, a phenomenon notable in the corrosion mechanism is that a large amount of hemimorphite is present in a uniformly corroded portion of the inner surface of a corroded water pipe other than a portion called a locally corroded rust bump. No corrosion has occurred in the lower part.
【０００７】このヘミモルファイトは、Ｚｎ4(ＯＨ）2
Ｓｉ2 Ｏ7 ・Ｈ2 Ｏの化学式を有する斜方晶系であっ
て、結晶は明瞭な異極像を示す。The hemimorphite is Zn 4 (OH) 2
A orthorhombic having Si 2 O 7 · H 2 O in the formula, the crystals show a clear hemimorphic.
【０００８】本発明者は、この現象の解明を基にして研
究を進めた結果、このヘミモルファイトの皮膜を金属基
材の耐食皮膜として利用することを思いつき、亜鉛・珪
酸塩複合皮膜が鉱物ヘミモルファイトに近似した組成構
造を有する場合、基材表面に人工的にヘミモルファイト
を形成することによって、これをとくに上水や雨水等の
淡水にさらされる配管や設備、構築物等の構造材の母材
金属の耐食皮膜として機能せしめることを思いついた。The present inventor has conducted research on the basis of elucidation of this phenomenon, and as a result, came up with the idea of using this hemimorphite coating as a corrosion-resistant coating on a metal substrate. When it has a compositional structure similar to hemimorphite, it is formed by artificially forming hemimorphite on the surface of the base material, which is especially used for structural materials such as pipes, facilities, and structures that are exposed to fresh water such as clean water or rainwater. Came up with a function as a corrosion-resistant coating of the base metal.
【０００９】[0009]
【発明が解決しようとする課題】本発明の目的は、家庭
内配管、湯沸かし器等の内壁面や外装鋼板の金属表面に
効果的に合成ヘミモルファイトの耐食皮膜を生成する手
段を提供することにある。SUMMARY OF THE INVENTION An object of the present invention is to provide a means for effectively forming a corrosion-resistant coating of synthetic hemimorphite on the inner wall surface of domestic pipes, water heaters and the like, and the metal surface of an exterior steel plate. is there.
【００１０】[0010]
【課題を解決するための手段】かかる目的は、亜鉛及び
珪素のアルコキシドを有機溶媒に溶かして得た溶液に水
蒸気を含む不活性気体を通気しながら攪拌して、溶液内
に水酸化亜鉛及び珪酸を共沈させ、その上澄み液を還流
して過剰の水分を除去した後、有機溶媒を揮発させて得
たゲル状の白色沈澱を、１００ｐｐｍ以上の溶性珪酸を
含むアルカリ珪酸塩溶液で希釈してヘミモルファイトの
前駆物質とし、このスラリー状の懸濁液を基材表面に塗
布し、加温あるいは加圧加温した水中で結晶を熟成する
ことによって達成される。SUMMARY OF THE INVENTION An object of the present invention is to provide a solution obtained by dissolving zinc and silicon alkoxides in an organic solvent, while stirring an inert gas containing water vapor while passing the solution through the solution. Is coprecipitated, and the supernatant is refluxed to remove excess water.The gelled white precipitate obtained by evaporating the organic solvent is diluted with an alkali silicate solution containing 100 ppm or more of soluble silicic acid. This is achieved by applying a slurry suspension as a precursor of hemimorphite to a substrate surface and aging the crystals in heated or pressurized water.
【００１１】上記、亜鉛及び珪素のアルコキシドを溶か
した有機溶媒中のＺｎ／Ｓｉのモル比が１．８〜２．２
であることが、ヘミモルファイトの原素組成に近い前駆
物質を合成できる点で望ましい。The molar ratio of Zn / Si in the organic solvent in which the alkoxides of zinc and silicon are dissolved is 1.8 to 2.2.
Is desirable in that a precursor having a composition close to that of hemimorphite can be synthesized.
【００１２】また、亜鉛及び珪素のアルコキシドが、そ
れぞれ亜鉛ジエトキシド〔Ｚｎ（ＯＣ2 Ｈ5 ）2 〕とオ
ルト珪酸エチル〔（Ｃ2 Ｈ5 Ｏ）4 Ｓｉ〕であり、且つ
有機溶媒がジメチルスルホキシド〔（ＣＨ3 ）2 ＳＯ〕
とすることが、溶媒への亜鉛及び珪酸原料の溶解性の点
から望ましい。The alkoxides of zinc and silicon are zinc diethoxide [Zn (OC 2 H 5 ) 2 ] and ethyl orthosilicate [(C 2 H 5 O) 4 Si], respectively, and the organic solvent is dimethyl sulfoxide [ (CH 3 ) 2 SO]
Is desirable from the viewpoint of solubility of the zinc and silicic acid raw materials in the solvent.
【００１３】[0013]
【作用】亜鉛及び珪素のアルコキシドを溶媒に溶かして
得た沈澱物を水蒸気を通気しながら攪拌することによっ
て、亜鉛のアルコキシドは、加水分解により水酸化亜鉛
とアルコールになり、珪素のアルコキシドは、珪酸とア
ルコールになる。そして水酸化亜鉛と珪酸はお互いに吸
着しながら白色の沈澱を生じる。このとき亜鉛と珪素の
比率が２対１になるように予め、亜鉛のアルコキシドと
珪素のアルコキシドの混合比率を選定しておけば、ヘミ
モルファイト〔Ｚｎ4 Ｓｉ2 Ｏ7 （ＯＨ）2 ・Ｈ2 Ｏ〕
の結晶中のＺｎ／Ｓｉ比率と同じため、この白色沈澱は
ヘミモルファイトの前駆物質として最適な組成を持つこ
とになる。The precipitate obtained by dissolving zinc and silicon alkoxides in a solvent is agitated while passing steam, whereby the zinc alkoxide is converted into zinc hydroxide and alcohol by hydrolysis, and the silicon alkoxide is converted into silicate And become alcohol. Then, zinc hydroxide and silicic acid form a white precipitate while adsorbing each other. At this time, if the mixing ratio of zinc alkoxide and silicon alkoxide is selected in advance so that the ratio of zinc to silicon is 2: 1, hemimorphite [Zn 4 Si 2 O 7 (OH) 2 .H 2 O]
Because of the same Zn / Si ratio in the crystals of the above, this white precipitate has an optimal composition as a precursor of hemimorphite.
【００１４】これを、基材表面に塗布して熟成すること
によって、Ｚｎ4 Ｓｉ2 Ｏ7 （ＯＨ）2 ・Ｈ2 Ｏの化学
式を有するヘミモルファイトの結晶体が形成される。This is applied to the surface of the substrate and aged to form a hemimorphite crystal having a chemical formula of Zn 4 Si 2 O 7 (OH) 2 .H 2 O.
【００１５】[0015]
【実施例】亜鉛ジエトキシド〔Ｚｎ（ＯＣ2 Ｈ5 ）2 〕
１．０８ｇとオルト珪酸エチル〔（Ｓｉ（ＯＣ2 Ｈ5 ）
4 〕０．７２４ｇをジメチルスルホキシド〔（ＣＨ3 ）
2 ＳＯ〕にＮ2 雰囲気中で溶かし、よく攪拌混合した
後、５０℃の温水中をバブリングさせたアルゴンガスを
この溶液に通気しながら攪拌させて、溶液中に白色の沈
澱を生じさせた。その後、溶液を８５℃に保持し、減圧
しながら還流し、溶液中の過剰の水分やアルコールを除
去した後、余分な溶媒を揮発させて、スラリー状のヘミ
モルファイトの前駆物質を得た。これを溶性珪酸１００
０ｐｐｍを含むメタ珪酸ナトリウム溶液で希釈して亜鉛
の基板に塗布し、８５℃の蒸留水中に浸漬して１週間熟
成し表面の生成物をＸ線回折法により分析したところ、
図１に示すようにヘミモルファイトの明確な回折パター
ンが確認できた。なお、図２にヘミモルファイトの標準
試料の回折パターンを示す。図２中の付番１のピークは
ヘミモルファイトの代表的な回析線である。EXAMPLE Zinc diethoxide [Zn (OC 2 H 5 ) 2 ]
1.08 g and ethyl orthosilicate [(Si (OC 2 H 5 )
4 ] 0.724 g of dimethyl sulfoxide [(CH 3 )
2 SO] in an N 2 atmosphere and mixed well with stirring. The mixture was stirred while passing argon gas bubbled through warm water at 50 ° C. through the solution to form a white precipitate in the solution. Thereafter, the solution was maintained at 85 ° C. and refluxed under reduced pressure to remove excess water and alcohol in the solution, and then the excess solvent was volatilized to obtain a slurry-like hemimorphite precursor. This is dissolved silica 100
Diluted with a sodium metasilicate solution containing 0 ppm, applied to a zinc substrate, immersed in distilled water at 85 ° C., aged for 1 week, and analyzed the products on the surface by X-ray diffraction.
As shown in FIG. 1, a clear diffraction pattern of hemimorphite was confirmed. FIG. 2 shows a diffraction pattern of a standard sample of hemimorphite. The peak numbered 1 in FIG. 2 is a typical diffraction line of hemimorphite.
【００１６】この皮膜を有する試料を８５℃の水道水中
に１週間放置して腐食試験を行ったところ、発錆面積は
１０％程度であった。A sample having this film was left in tap water at 85 ° C. for one week to conduct a corrosion test. As a result, the rusting area was about 10%.
【００１７】比較のために、ペースト状のヘミモルファ
イト前駆物質を塗布し、蒸留水中での熟成を行わない場
合のＸ線回折を行ったところ、図３に示す回折像を得
た。その結果この皮膜は、ヘミモルファイトを含まない
ものであることが判る。For comparison, a paste-like hemimorphite precursor was applied and subjected to X-ray diffraction without aging in distilled water. As a result, a diffraction image shown in FIG. 3 was obtained. As a result, it is found that this film does not contain hemimorphite.
【００１８】そして、このヘミモルファイトが合成され
ない皮膜を有する試料を同様の腐食試験に供したとこ
ろ、その腐食の態様は、ほぼ５０％の面積に白錆が発生
した。When a sample having a film on which hemimorphite was not synthesized was subjected to a similar corrosion test, white rust was generated in almost 50% of the area of the corrosion.
【００１９】この結果、同様の化学的組成を有する皮膜
であっても、ヘミモルファイトを合成したものは、ヘミ
モルファイトの結晶化が進んでいない皮膜を有するもの
よりも格段に優れた特性を有するものであることが判
る。As a result, even if the coating has the same chemical composition, the one obtained by synthesizing hemimorphite has much more excellent characteristics than the one having a coating in which the crystallization of hemimorphite has not progressed. It turns out that it has.
【００２０】[0020]
【発明の効果】本発明によって以下の効果を奏する。According to the present invention, the following effects can be obtained.
【００２１】（１）基材上にヘミモルファイトを有する
皮膜が比較的簡単に形成され、得られた皮膜は上水や雨
水や大気中等の自然環境下で非常に安定であるため、下
地の金属基材を長期にわたり防食することができる。(1) A film having hemimorphite is relatively easily formed on a substrate, and the obtained film is very stable under natural environments such as tap water, rainwater, and the atmosphere. The metal substrate can be protected for a long time.
【００２２】（２）ヘミモルファイトは熱分解温度が２
５０℃以上と高いため、生成した皮膜は熱水環境下でも
安定な耐食皮膜として作用する。(2) Hemimorphite has a thermal decomposition temperature of 2
Since the temperature is as high as 50 ° C. or higher, the formed film functions as a stable corrosion-resistant film even in a hot water environment.
【図１】 本発明によって得られた皮膜のＸ線回折像を
示す。FIG. 1 shows an X-ray diffraction image of a film obtained according to the present invention.
【図２】 天然のヘミモルファイトのＸ線回折像を示
す。FIG. 2 shows an X-ray diffraction image of natural hemimorphite.
【図３】 ヘミモルファイトが合成されない皮膜のＸ線
回折像を示す。FIG. 3 shows an X-ray diffraction image of a film in which hemimorphite is not synthesized.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 永田 英樹 福岡県北九州市小倉北区中島２丁目１番 １号 東陶機器株式会社内 (72)発明者 雨宮 隆 福岡県北九州市小倉北区中島２丁目１番 １号 東陶機器株式会社内 (56)参考文献 特開 平５−195252（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) C23C 18/12 B05D 7/24 302 C01B 33/12 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hideki Nagata 2-1-1 Nakajima, Kokurakita-ku, Kitakyushu-shi, Fukuoka Tochiki Kiki Co., Ltd. (72) Inventor Takashi Amemiya 2 Nakajima, Kokurakita-ku, Kitakyushu-shi, Fukuoka Chome 1-1 No. 1 Toto Kiki Co., Ltd. (56) References JP-A-5-195252 (JP, A) (58) Fields investigated (Int. Cl. 7 , DB name) C23C 18/12 B05D 7 / 24 302 C01B 33/12
Claims (3)
に溶かして得た溶液に水蒸気を含む不活性気体を通気し
ながら攪拌して、溶液内に水酸化亜鉛及び珪酸を共沈さ
せた後、過剰の水分を除去後、溶媒を揮発させて得たゲ
ル上の白色沈澱をアルカリ珪酸塩溶液で希釈してヘミモ
ルファイトの前駆物質として金属基材表面へ塗布し、そ
の金属基材を温水中で熟成してヘミモルファイトの前駆
物質を結晶化させる合成ヘミモルファイト耐食皮膜の形
成方法。1. A solution obtained by dissolving zinc and silicon alkoxides in an organic solvent is stirred while passing an inert gas containing water vapor, so that zinc hydroxide and silicic acid are coprecipitated in the solution, and then excess After removing the water, the white precipitate on the gel obtained by evaporating the solvent is diluted with an alkali silicate solution and applied to the surface of a metal substrate as a precursor of hemimorphite, and the metal substrate is heated in warm water. A method for forming a synthetic hemimorphite corrosion-resistant film that ages to crystallize a hemimorphite precursor.
のアルコキシドを溶かした有機溶媒中のＺｎ／Ｓｉのモ
ル比が１．８〜２．２である合成ヘミモルファイト耐食
皮膜の形成方法。2. The method according to claim 1, wherein the molar ratio of Zn / Si in the organic solvent in which the alkoxides of zinc and silicon are dissolved is 1.8 to 2.2.
のアルコキシドが、それぞれ亜鉛ジエトキシド〔Ｚｎ
（ＯＣ2 Ｈ5 ）2 〕とオルト珪酸エチル〔（Ｃ2 Ｈ
5 Ｏ）4 Ｓｉ〕であり、且つ有機溶媒がジメチルスルホ
キシド〔（ＣＨ3 ）2 ＳＯ〕である合成ヘミモルファイ
ト耐食皮膜の形成方法。3. The method according to claim 1, wherein the alkoxides of zinc and silicon are each zinc ethoxide [Zn
(OC 2 H 5 ) 2 ] and ethyl orthosilicate [(C 2 H
5 O) 4 Si] and the organic solvent is dimethyl sulfoxide [(CH 3 ) 2 SO].
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP04007851A JP3113719B2 (en) | 1992-01-20 | 1992-01-20 | Method of forming synthetic hemimorphite corrosion resistant film |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP04007851A JP3113719B2 (en) | 1992-01-20 | 1992-01-20 | Method of forming synthetic hemimorphite corrosion resistant film |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05195233A JPH05195233A (en) | 1993-08-03 |
| JP3113719B2 true JP3113719B2 (en) | 2000-12-04 |
Family
ID=11677132
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP04007851A Expired - Fee Related JP3113719B2 (en) | 1992-01-20 | 1992-01-20 | Method of forming synthetic hemimorphite corrosion resistant film |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3113719B2 (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2203181C (en) * | 1994-10-21 | 2001-08-07 | Robert L. Heimann | Corrosion preventing buffer system for metal products |
| US5938976A (en) * | 1994-10-21 | 1999-08-17 | Elisha Technologies Co. L.L.C. | Corrosion resistant coatings containing an amorphous phase |
| US6143420A (en) * | 1994-10-21 | 2000-11-07 | Elisha Technologies Co Llc | Corrosion resistant coatings containing an amorphous phase |
| US5714093A (en) * | 1994-10-21 | 1998-02-03 | Elisha Technologies Co. L.L.C. | Corrosion resistant buffer system for metal products |
| US5928796A (en) * | 1994-10-21 | 1999-07-27 | Elisha Technologies Co Llc | Corrosion resistant coatings containing an amorphous phase |
| US6080334A (en) * | 1994-10-21 | 2000-06-27 | Elisha Technologies Co Llc | Corrosion resistant buffer system for metal products |
| US6165257A (en) * | 1994-10-21 | 2000-12-26 | Elisha Technologies Co. Llc | Corrosion resistant coatings containing an amorphous phase |
| EP4101920A4 (en) * | 2020-02-06 | 2024-02-21 | O&K Company | Lubricant composition for forming hemimorphite-containing lubrication coating, method for forming said lubrication coating on surface of metal workpiece, and metal workpiece comprising said lubrication coating |
-
1992
- 1992-01-20 JP JP04007851A patent/JP3113719B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH05195233A (en) | 1993-08-03 |
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