EP0102874B1 - Bad zum chemischen Abscheiden von Nickel- oder Kobaltüberzügen unter Verwendung eines Reduktionmittels auf der Basis von Bor oder Phosphor - Google Patents

Bad zum chemischen Abscheiden von Nickel- oder Kobaltüberzügen unter Verwendung eines Reduktionmittels auf der Basis von Bor oder Phosphor Download PDF

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Publication number
EP0102874B1
EP0102874B1 EP83401550A EP83401550A EP0102874B1 EP 0102874 B1 EP0102874 B1 EP 0102874B1 EP 83401550 A EP83401550 A EP 83401550A EP 83401550 A EP83401550 A EP 83401550A EP 0102874 B1 EP0102874 B1 EP 0102874B1
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EP
European Patent Office
Prior art keywords
bath
stabilizing agent
nickel
stabilizing
nitrogen
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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
Application number
EP83401550A
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English (en)
French (fr)
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EP0102874A1 (de
Inventor
Pierre Josso
Pierre Lepetit
Marcel Massard
Pierre Mazars
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Office National dEtudes et de Recherches Aerospatiales ONERA
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Office National dEtudes et de Recherches Aerospatiales ONERA
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Publication of EP0102874A1 publication Critical patent/EP0102874A1/de
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Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
    • C23C18/16—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by reduction or substitution, e.g. electroless plating
    • C23C18/31—Coating with metals
    • C23C18/32—Coating with nickel, cobalt or mixtures thereof with phosphorus or boron
    • C23C18/34—Coating with nickel, cobalt or mixtures thereof with phosphorus or boron using reducing agents

Definitions

  • the invention relates to a bath for the chemical deposition of nickel and / or cobalt using a boron or phosphorus-based reducing agent.
  • All the baths currently used for the deposition by chemical that is to say by auto-catalytic, nickel and / or cobalt, whether acid baths or alkaline baths, use a reducing agent based on boron or phosphorus in the form of alkaline hypophosphite or hydrogenated boron derivative.
  • a reducing agent based on boron or phosphorus in the form of alkaline hypophosphite or hydrogenated boron derivative.
  • they contain one or more salts of the metal or metals to be deposited, one or more complexing agents of this metal (or of these metals) and a stabilizer.
  • the role of the complexing agent is to keep the metal in solution and to release it as the deposition reaction proceeds.
  • the stabilizer is essential for a self-catalyzed reaction such as that occurring here, in order to slow down the speed of the deposition reaction and therefore allow the desired regular deposition to be obtained on the part.
  • the stabilizers used industrially are, for acid baths, mineral or organic derivatives of sulfur and, for alkaline baths, compounds of metals or metalloids of groups Illb, IVb and Vb of the periodic table of the elements, and in particular thallium.
  • He is concerned, among other things, with the development of metal parts, for example turbine blades, intended to operate at very high temperatures and in highly corrosive gases, in particular sulfur gases, and has developed a surface treatment process for protecting such alloys by chromaluminization (French Patent No. 2,278,794), which thermochemical treatment must be carried out on parts previously coated with a nickel deposit, advantageously produced chemically.
  • French patent application 2 329 762 proposes a type of stabilizer different from those usually used, consisting of an iodized organic compound. These compounds do not eliminate the drawbacks of the usual stabilizers because the presence of iodine causes effects comparable to the presence of sulfur. The same can be said of other halogens.
  • the Applicant has therefore sought to develop a chemical nickel and / or cobalt deposition bath comprising a stabilizer which does not lead to the drawbacks, mentioned above, of the previously known stabilizers.
  • the bath according to the invention is in accordance with claim 1.
  • Boron, aluminum, carbon, nitrogen, phosphorus, oxygen, fluorine and chlorine are acceptable constituents of the stabilizer, either because they are not included in the deposit, or because they can be eliminated, either because they do not cause a corrosive or toxic effect.
  • fluorine and chlorine can be eliminated. If you want to avoid this operation, you must choose a stabilizer that does not include any metalloid from the Vlla group.
  • Nickel for example, has a 3d layer which, instead of having 10 electrons, has 8, and a 4s layer which has two electrons and is therefore saturated. To find a certain electronic stability, nickel tends to lose the two electrons of its layer 4s (by oxidative attacks thus leading to the cation Ni 2+ ) or to capture two electrons to saturate its layer 3d (chemisorption). During chemical deposition, the reducing agent tends to oxidize on contact with nickel, which in turn tends to reduce.
  • heterocycles of aromatic nature comprising one or more heteroatoms of nitrogen and / or oxygen, as defined in claim 1.
  • the stabilizer can thus be chosen from 5-atom nitrogen heterocycles comprising one or more nitrogen atoms, for example pyrrole, indole, purine, pyrazole, triazole, tetrazole and similar compounds.
  • the stabilizer can also be chosen from nitrogen heterocycles with 6 atoms comprising one or more nitrogen atoms in the ring, for example pyridine, cinnoline, pyridazine, pyrimidine, pyrazine and the like.
  • EP-A-0 066 656 published after the priority date of this Application, discloses the presence of imidazole, to the exclusion of any other nitrogen heterocycle, in a chemical deposition bath comparable elsewhere to that of invention. This document does not indicate that imidazole plays the role of stabilizer.
  • heterocycles can be substituted on one or more of their carbon atoms, the substituent possibly being in particular a hydrocarbon radical, an alcohol, carboxylic acid, ether, ester or amine, an aliphatic or aromatic derivative, a halogen atom, or a nitro or nitroso type substituent.
  • substituents may be present on at least one of them, provided that at least one unsubstituted nitrogen atom remains, otherwise the easily detected electronic doublet would disappear.
  • N-methylpyridinium chloride does not have stabilizing properties and that a chemical deposition bath containing this compound decomposes very quickly, which is explained by the masking of the electronic doublet by the substituent .
  • heterocycles in which at least two adjacent atoms (carbon or nitrogen) carry substituents which together form an aromatic ring, provided that at least one unsubstituted nitrogen atom remains.
  • substituted nitrogen heterocycles examples include nicotinic acid (a-pyridinecarboxylic), cinnolic acid (a. A-pyridine-dicarboxylic), 2-aminoquinoline, riboflavin, acridine.
  • Another type of compound which can be used as a stabilizer for a nickel and / or cobalt chemical deposition bath according to the invention consists of oxygenated heterocycles of aromatic nature and their substitution derivatives. Mention may be made of heterocycles with 5 atoms, for example furan, unsubstituted or substituted on one or more carbon atoms of the ring by substituents analogous to those defined above for nitrogen heterocycles.
  • a third type of compound which can be used as stabilizers consists of heavy ethers of the R-Q-R 'type. soluble in water, in which R and R 'are aliphatic radicals. Can be considered as heavy ethers those having a molecular mass sufficient not to lower the boiling point of the bath below 70 ° C, minimum temperature of industrial use of most baths. Ethers in which the radicals R and R 'each contain at least 3 carbon atoms are thus suitable.
  • the stabilizers according to the invention which have no sulfur, unwanted heavy metal or metalloid, are very satisfactory, in particular for coating parts of alloys intended to operate at very high temperatures or for the manufacture of parts intended to enter into contact with food products.
  • the type of stabilizer according to the invention acts directly on the metal of the deposit and can therefore be used whatever the reducing agent used.
  • a boron hydride reducing agent for example an alkaline borohydride such as NaBH 4 or KBH 4 or an aminoborane such as BH 3 , R 2 NH where R is an aliphatic radical
  • the addition of a secondary stabilizer is made necessary in order to slow down the activity of the reducing agent, as usual in the chemical deposition baths hitherto used employing primary sulfur or heavy metal stabilizers.
  • a chromium compound is advantageously used for weakly acidic or moderately alkaline baths and an arsenic compound for strongly alkaline baths.
  • the baths according to the invention can comprise a single compound or a mixture of stabilizing compounds.
  • the stabilizer content is between limits varying according to the operating conditions. If the bath contains too small a quantity of stabilizer, spontaneous decomposition of the bath takes place and if, on the other hand, it contains an excess of stabilizer, the speed is then practically zero.
  • the concentration of the stabilizing bath is between approximately 5.7 ⁇ 10-3 and 6.9 10 ⁇ 3 M and that it is preferably from 1 '' 6.3 ⁇ 10 -3 M.
  • the stabilizer concentration is advantageously between approximately 2.5 ⁇ 10 -4 and 3.5 ⁇ 10 -4 M, and it is preferably of the order of 3 ⁇ 10 -4 M.
  • the invention is illustrated below by a few examples of baths which are in no way to be considered as limiting.
  • the concentrations indicated are expressed in mole / liter (molar concentration).
  • Examples are given of weakly acid baths, weakly alkaline baths and alkaline baths, using boron-based or phosphorus-based reducing agents.
  • the pH is adjusted between 5.0 and 5.5 using dilute ammonia.
  • the temperature for using such a bath is between 50 and 80 ° C.
  • a deposition rate of the order of 10 ⁇ m / h was obtained for a diethylaminoborane concentration of 2.5 g / l at a bath temperature of 72 ° C.
  • the pH of the bath is adjusted between 6.0 and 6.5 using dilute ammonia.
  • the temperature for using such a bath is between 70 and 80 ° C.
  • Example 2 A bath identical to that of Example 2 is prepared, except that cobalt chloride hexahydrate in a concentration of 0.2 M is used in place of nickel chloride hexahydrate.
  • the temperature for using such a bath is between 70 and 80 ° C.
  • This bath was tested using an aqueous solution of dimethylaminoborane as a reducing agent.
  • Example 2 A bath identical to that of Example 2 is prepared, except that nickel chloride hexahydrate is used in a concentration of 0.17 M and cobalt chloride hexahydrate in a concentration of 0.042 M at instead of only nickel chloride hexahydrate.
  • the temperature of use of this bath is between 70 and 80 ° C.
  • good complexing agents consist of ammonium salts.
  • the pH of the bath is adjusted between 7.0 and 8.0 using dilute ammonia.
  • the bath is tested with, as reducing agent, an aqueous solution of dimethylaminoborane.
  • the pH is then between 13 and 14.
  • This bath is tested with, as reducing agent, an aqueous solution of sodium borohydride.

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  • Chemical & Material Sciences (AREA)
  • General Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Chemically Coating (AREA)
  • Electroplating And Plating Baths Therefor (AREA)

Claims (12)

1. Bad zum chemischen Abscheiden von Nickel- und/oder Kobaltüberzügen, bestehend aus einem Salz des abzuscheidenden Metalls (bzw. der abzuscheidenden Metalle), einem oder mehreren Komplexbildnern dieses Metalls (bzw. dieser Metalle), einem Reduktionsmittel auf der Basis von Bor oder Phosphor und einem Stabilisierungsmittel, dadurch gekennzeichnet, daß das Stabilisierungsmittel eine organische wasserlösliche Verbindung ist, die weder Schwefel noch ein anderes Metall oder Nichtmetall der Gruppen Illb (ausgenommen Bor und Aluminium), IVb (ausgenommen Kohlenstoff), Vb (ausgenommen Stickstoff und Phosphor), Vlb (ausgenommen Sauerstoff) und Vllb (ausgenommen Fluor und Chlor) enthält und die über ein Dublett verfügt. welches von Nickel und/oder Kobalt leicht gebunden werden kann, wobei dieses Stabilisierungsmittel eine aromatische heterocyclische Verbindung mit einem oder mehreren Stickstoff-und/oder Sauerstoff-Heteroatomen mit Ausnahme von Imidazol oder ein wasserlöslicher Äther entsprechend der Formel R―O―R' ist, wobei R und R' jeweils über mindestens drei Kohlenstoffatome verfügen.
2. Bad gemäß Anspruch 1, dadurch gekennzeichnet, daß das Stabilisierungsmittel kein Nichtmetall der Gruppe Vllb enthält.
3. Bad gemäß Anspruch 1 oder 2, dadurch gekennzeichnet, daß das Stabilisierungsmittel eine aromatische heterocyclische Verbindung mit einem Stickstoff-Heteroatom ist.
4. Bad gemäß Anspruch 3, dadurch gekennzeichnet, daß das Stabilisierungsmittel eine heterocyclische Verbindung mit 5 Atomen ist, deren Ring ein Stickstoffatom enthält, oder eines ihrer Derivate mit N- oder C-Substituenten.
5. Bad gemäß Anspruch 3, dadurch gekennzeichnet, daß das Stabilisierungsmittel Pyrrol oder Indol ist.
6. Bad gemäß Anspruch 3, dadurch gekennzeichnet, daß das Stabilisierungsmittel eine heterocyclische Verbindung mit sechs Atomen ist, deren Ring ein Stickstoffatom enthält, oder eines ihrer Derivate mit N- oder C-Substituenten.
7. Bad gemäß Anspruch 6, dadurch gekennzeichnet, daß das Stabilisierungsmittel Pyridin ist.
8. Bad gemäß Anspruch 1, dadurch gekennzeichnet, daß das Stabilisierungsmittel eine oxidierte heterocyclische Verbindung mit fünf Atomen oder eines ihrer substituierten Derivate ist.
9. Bad gemäß Anspruch 8, dadurch gekennzeichnet, daß das Stabilisierungsmittel Furan ist.
10. Bad gemäß einem der oben genannten Ansprüche, dadurch gekennzeichnet, daß es eine Mischung aus mehreren stabilisierenden Verbindungen enthält.
11. Bad gemäß einem der oben genannten Ansprüche, dadurch gekennzeichnet, daß die stabilisierende(n) Verbindung(en) bei einem sauren Bad in einer Stoffmengen-Konzentration zwischen ca. 5,7 x 10--3 M und 6,9 x 10-3 M, vorzugsweise in der Größenordnung von 6,3 x 10-3 M vorliegt (bzw. vorliegen).
12. Bad gemäß einem der Ansprüche 1 bis 11, dadurch gekennzeichnet, daß die stabilisierende(n) Verbindung(en) bei einem alkalischen Bad in einer Stoffmengen-Konzentration zwischen ca. 2,5 x 10-4 M und 3,5 x 10-4 M, vorzugsweise in der Größenordnung von 3 x 10-4 M vorliegt (bzw. vorliegen).
EP83401550A 1982-07-30 1983-07-27 Bad zum chemischen Abscheiden von Nickel- oder Kobaltüberzügen unter Verwendung eines Reduktionmittels auf der Basis von Bor oder Phosphor Expired EP0102874B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8213431A FR2531103B1 (fr) 1982-07-30 1982-07-30 Bain pour le depot chimique de nickel et/ou de cobalt utilisant un reducteur a base de bore ou de phosphore
FR8213431 1982-07-30

Publications (2)

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EP0102874A1 EP0102874A1 (de) 1984-03-14
EP0102874B1 true EP0102874B1 (de) 1986-12-03

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EP83401550A Expired EP0102874B1 (de) 1982-07-30 1983-07-27 Bad zum chemischen Abscheiden von Nickel- oder Kobaltüberzügen unter Verwendung eines Reduktionmittels auf der Basis von Bor oder Phosphor

Country Status (5)

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US (1) US4486233A (de)
EP (1) EP0102874B1 (de)
JP (1) JPS5943857A (de)
DE (1) DE3368088D1 (de)
FR (1) FR2531103B1 (de)

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4624865A (en) * 1984-05-21 1986-11-25 Carolina Solvents, Inc. Electrically conductive microballoons and compositions incorporating same
US5017410A (en) * 1988-05-23 1991-05-21 United Technologies Corporation Wear resistant electroless nickel-boron coating compositions
US5196053A (en) * 1991-11-27 1993-03-23 Mcgean-Rohco, Inc. Complexing agent for displacement tin plating
JP2968147B2 (ja) * 1993-04-07 1999-10-25 日本パーカライジング株式会社 亜鉛含有金属めっき鋼板用酸性置換めっき液組成物
US5624480A (en) * 1993-04-07 1997-04-29 Henkel Corporation Composition and process for substitutionally plating zinciferous surfaces
CA2178146C (en) * 1995-06-06 2002-01-15 Mark W. Zitko Electroless nickel cobalt phosphorous composition and plating process
US6183546B1 (en) 1998-11-02 2001-02-06 Mccomas Industries International Coating compositions containing nickel and boron
FR2787472B1 (fr) 1998-12-16 2001-03-09 Onera (Off Nat Aerospatiale) Procede pour produire une poudre d'alliage metallique de type mcraly et revetements obtenus avec cette poudre
EP1306465B1 (de) * 2001-10-24 2011-03-16 Rohm and Haas Electronic Materials LLC Stabilisatoren für Lösungen zur stromlosen Metallisierung und Verfahren zu deren Anwendung
KR100859259B1 (ko) * 2005-12-29 2008-09-18 주식회사 엘지화학 캡층 형성을 위한 코발트 계열 합금 무전해 도금 용액 및이를 이용하는 무전해 도금 방법
JP2019210501A (ja) * 2018-06-01 2019-12-12 奥野製薬工業株式会社 無電解ニッケルめっき液用安定剤、並びにそれを用いためっき液、めっき方法及び分析方法

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0066656A1 (de) * 1981-06-02 1982-12-15 Asahi Glass Company Ltd. Verfahren zur Herstellung einer Nickelschicht

Family Cites Families (4)

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Publication number Priority date Publication date Assignee Title
US3147154A (en) * 1961-05-25 1964-09-01 Texaco Inc Method of depositing metal-containing material onto an extended surface
CA1079454A (en) * 1975-11-03 1980-06-17 Michael Gulla Electroless nickel plating
JPS56108869A (en) * 1980-01-31 1981-08-28 Asahi Glass Co Ltd Nickel coat forming method
US4368223A (en) * 1981-06-01 1983-01-11 Asahi Glass Company, Ltd. Process for preparing nickel layer

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0066656A1 (de) * 1981-06-02 1982-12-15 Asahi Glass Company Ltd. Verfahren zur Herstellung einer Nickelschicht

Also Published As

Publication number Publication date
FR2531103A1 (fr) 1984-02-03
US4486233A (en) 1984-12-04
FR2531103B1 (fr) 1985-11-22
DE3368088D1 (en) 1987-01-15
EP0102874A1 (de) 1984-03-14
JPS5943857A (ja) 1984-03-12

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