GB2039532A - Electrolyte for the electrodeposition of white gold - Google Patents
Electrolyte for the electrodeposition of white gold Download PDFInfo
- Publication number
- GB2039532A GB2039532A GB7944282A GB7944282A GB2039532A GB 2039532 A GB2039532 A GB 2039532A GB 7944282 A GB7944282 A GB 7944282A GB 7944282 A GB7944282 A GB 7944282A GB 2039532 A GB2039532 A GB 2039532A
- Authority
- GB
- United Kingdom
- Prior art keywords
- electrolyte
- gold
- cyanide
- nickel
- carboxylic acid
- 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.)
- Withdrawn
Links
- 239000003792 electrolyte Substances 0.000 title claims abstract description 34
- 229910000832 white gold Inorganic materials 0.000 title claims abstract description 15
- 239000010938 white gold Substances 0.000 title claims abstract description 14
- 238000004070 electrodeposition Methods 0.000 title claims description 5
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims abstract description 22
- 238000000576 coating method Methods 0.000 claims abstract description 13
- 229910052759 nickel Inorganic materials 0.000 claims abstract description 11
- 239000003513 alkali Substances 0.000 claims abstract description 7
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 6
- IZLAVFWQHMDDGK-UHFFFAOYSA-N gold(1+);cyanide Chemical compound [Au+].N#[C-] IZLAVFWQHMDDGK-UHFFFAOYSA-N 0.000 claims abstract description 6
- -1 nitrogen-containing compound Chemical class 0.000 claims abstract description 6
- 150000001412 amines Chemical class 0.000 claims abstract description 4
- BVKZGUZCCUSVTD-UHFFFAOYSA-N carbonic acid Chemical compound OC(O)=O BVKZGUZCCUSVTD-UHFFFAOYSA-N 0.000 claims abstract description 4
- 125000001931 aliphatic group Chemical group 0.000 claims abstract description 3
- 229910017052 cobalt Inorganic materials 0.000 claims abstract description 3
- 239000010941 cobalt Substances 0.000 claims abstract description 3
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims abstract description 3
- 229910052738 indium Inorganic materials 0.000 claims abstract description 3
- APFVFJFRJDLVQX-UHFFFAOYSA-N indium atom Chemical compound [In] APFVFJFRJDLVQX-UHFFFAOYSA-N 0.000 claims abstract description 3
- 229910052742 iron Inorganic materials 0.000 claims abstract description 3
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 claims description 15
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 12
- LGQLOGILCSXPEA-UHFFFAOYSA-L nickel sulfate Chemical group [Ni+2].[O-]S([O-])(=O)=O LGQLOGILCSXPEA-UHFFFAOYSA-L 0.000 claims description 9
- OBITVHZFHDIQGH-UHFFFAOYSA-N [Au].[K]C#N Chemical group [Au].[K]C#N OBITVHZFHDIQGH-UHFFFAOYSA-N 0.000 claims description 6
- 229910052751 metal Inorganic materials 0.000 claims description 5
- 239000002184 metal Substances 0.000 claims description 5
- 238000000034 method Methods 0.000 claims description 5
- UVZICZIVKIMRNE-UHFFFAOYSA-N thiodiacetic acid Chemical compound OC(=O)CSCC(O)=O UVZICZIVKIMRNE-UHFFFAOYSA-N 0.000 claims description 5
- 150000001735 carboxylic acids Chemical class 0.000 claims description 4
- 150000002815 nickel Chemical class 0.000 claims description 4
- 239000003607 modifier Substances 0.000 abstract 1
- CWERGRDVMFNCDR-UHFFFAOYSA-N thioglycolic acid Chemical compound OC(=O)CS CWERGRDVMFNCDR-UHFFFAOYSA-N 0.000 abstract 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 9
- 239000010931 gold Substances 0.000 description 9
- 229910052737 gold Inorganic materials 0.000 description 8
- 238000000151 deposition Methods 0.000 description 4
- 230000008021 deposition Effects 0.000 description 4
- 229910001020 Au alloy Inorganic materials 0.000 description 3
- 238000007792 addition Methods 0.000 description 3
- 238000005494 tarnishing Methods 0.000 description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- XFXPMWWXUTWYJX-UHFFFAOYSA-N Cyanide Chemical compound N#[C-] XFXPMWWXUTWYJX-UHFFFAOYSA-N 0.000 description 2
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 229910052709 silver Inorganic materials 0.000 description 2
- 239000004332 silver Substances 0.000 description 2
- BJEPYKJPYRNKOW-REOHCLBHSA-N (S)-malic acid Chemical compound OC(=O)[C@@H](O)CC(O)=O BJEPYKJPYRNKOW-REOHCLBHSA-N 0.000 description 1
- QGLWBTPVKHMVHM-KTKRTIGZSA-N (z)-octadec-9-en-1-amine Chemical compound CCCCCCCC\C=C/CCCCCCCCN QGLWBTPVKHMVHM-KTKRTIGZSA-N 0.000 description 1
- 229910001316 Ag alloy Inorganic materials 0.000 description 1
- 238000012935 Averaging Methods 0.000 description 1
- 229910000881 Cu alloy Inorganic materials 0.000 description 1
- IAYPIBMASNFSPL-UHFFFAOYSA-N Ethylene oxide Chemical compound C1CO1 IAYPIBMASNFSPL-UHFFFAOYSA-N 0.000 description 1
- 229910000990 Ni alloy Inorganic materials 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- BJEPYKJPYRNKOW-UHFFFAOYSA-N alpha-hydroxysuccinic acid Natural products OC(=O)C(O)CC(O)=O BJEPYKJPYRNKOW-UHFFFAOYSA-N 0.000 description 1
- 239000007844 bleaching agent Substances 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000007046 ethoxylation reaction Methods 0.000 description 1
- 239000003292 glue Substances 0.000 description 1
- MSNOMDLPLDYDME-UHFFFAOYSA-N gold nickel Chemical compound [Ni].[Au] MSNOMDLPLDYDME-UHFFFAOYSA-N 0.000 description 1
- 239000001630 malic acid Substances 0.000 description 1
- 235000011090 malic acid Nutrition 0.000 description 1
- 229910000363 nickel(II) sulfate Inorganic materials 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 150000003628 tricarboxylic acids Chemical class 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D3/00—Electroplating: Baths therefor
- C25D3/02—Electroplating: Baths therefor from solutions
- C25D3/56—Electroplating: Baths therefor from solutions of alloys
- C25D3/62—Electroplating: Baths therefor from solutions of alloys containing more than 50% by weight of gold
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Electroplating And Plating Baths Therefor (AREA)
Abstract
White gold coatings are electrodeposited from an electrolyte containing an alkali gold (I) cyanide, nickel, an aliphatic hydroxy-carboxylic acid and thioglycollic acid. Preferably, the electrolyte also contains a non-ionogenic nitrogen-containing compound of the ethoxylated fatty amine type, such as that commercially known as "Stockomin". Colour modifiers, such as cobalt, iron or indium, may be added to the bath.
Description
SPECIFICATION
Electrolyte for the electrodeposition of white gold
This invention lies within the field of electrolytic deposition of so-called "white golds," that is to say alloys of gold with metals that act to whiten or bleach the yellow colour of electrodeposited gold. The metal with which this invention is concerned is nickel.
It is known that gold and nickel can be deposited from electrolytes containing alkali cyanide, to yield a gold-nickel alloy. The deposition of the nickel takes place, however, only when the limiting current density for gold deposition is exceeded, and the deposits are not solutions of nickel in gold but mixtures of predominantly gold and predominantly nickel phases. Such deposits have neither the stability nor the resistance to corrosion which characterises single-phase solution alloys of gold, and are unacceptable commercially.
Attempts have been made to produce acceptable white gold coatings from electrolytes containing alkali gold (I) cyanide, a nickel salt and a hydroxy-carboxylic acid, with or without additives to improve the nature of the deposited coatings, but, as far as the applicant is aware, these attempts have not been fully successful.
The object of this invention is to provide an electrolyte from which white gold can be deposited to form commercially acceptable coatings as regards colour, brightness, resistance to tarnishing and other physical properties.
According to the present invention, we therefore provide an electrolyte for the electrodeposition of white gold comprising an alkali gold (I) cyanide, preferably potassium gold (i) cyanide, a water-soluble nickel salt, preferably nickel sulphate, and an organic carboxylic acid, preferably an aliphatic hydroxy-carboxylic acid, advantageously an aliphatic hydroxy di- or tri- carboxylic acid, with the further addition thereto of thiodiglycollic acid.
Further according to the invention, the electrolyte also contains a non-ionogenic nitrogen-containing compound of the ethoxylated fatty amine type.
In general, the basic aqueous electrolyte is made from potassium gold (I) cyanide, nickel in the form of nickel sulphate, citric acid and potassium hydroxide added in sufficient quantity to bring the pH of the bath to between 3.5 and 4.2. A suitable composition is:
Potassium gold(l) cyanide 1 to 4.5 glC, and preferably 2 to 3 g/6.
Nickel sulphate (NiSO4) 16 to 55 g/t, and preferably 35 to 40 g/.
Citric acid 40 to 100 glC, and preferably about 50 glut.
Potassium hydroxide to bring the pH to between 3.5 and 4.2.
(usually about 35 to 40 glue.) To this bath is added thiodiglycollic acid between 0.2 to 3 g/(.
It has been found that the quality of the coatings is further improved by the addition of a few drops (say 0.3my') to 2 mt of the non-ionogenic nitrogen-containing compound of the ethoxylated fatty amine type.
This may, for instance, be in the form of a compound of the type known under the trade name "Genamin C or 0" derived from oleylamine by a medium degree of ethoxylation (for example with 5 to 8 mole of ethylene oxide). One such compound is known commercially as "Stokomin," and its use in the bath described above, in an amount of 0.3 mPlt to 2m(/t, , has proved particularly suitable.
Malic acid can be substituted for citric acid, but is objectionable because of the generation of unpleasant odour.
It is pointed out that, since the two additions to the basic bath are consumed during the plating process, they must be replenished from time to time or continuously.
Suitable operating conditions are: temperature of the bath, between 40 and 60"C, (and preferably 60"C), current densities, between 0.5 and
3.0 Ad/m2, and preferably 1.5 A/dm2, movement of the electrolyte relatively to the cathode, between 4 and 20 cm/sec and preferably 8 cm/sec.
White gold coatings deposited under these conditions from the electrolyte described above and with a thickness of 5 pm or micrometres, have been found to be free of stress cracks, with micro-Vickers hardness numbers of from 350 to 500. The nickel content, dependent upon the conditions of deposition, is between 8 and 25%, averaging between 14 and 16%. X-ray examination showed that the nickel was present in the white gold deposit in solid soiution in the gold. The coatings were highly resistant to tarnishing and in artificial perspiration and salt-spray tests they underwent no significant change.
In order to achieve special colour tints in the coatings, other metals may be added to the bath, for example cobalt, iron or indium.
The electrolytes of the invention can be used to deposit white gold coatings directly upon gold, copper or silver, upon gold, copper or silver alloys and upon nickel or silver intermediate coatings. Since the coatings are resistant to tarnishing and corrosion, they are especially suitable for application to jewellery and other articles such as spectacle frames. They can be used for both single and multilayer coatings.
Claims (20)
1. An electrolyte for the electrodeposition of white gold comprising an alkali gold (I) cyanide, a nickel salt and an organic carboxylic acid, with the further addition thereto of thiodigly-collic acid.
2. An electrolyte as claimed in claim 2, where the said alkali gold (i) cyanide is potassium gold (I) cyanide.
3. An electrolyte as claimed in either of claims 1 and 2, wherein the said water-soluble nickel salt is nickel sulphate.
4. An electrolyte as claimed in any one of the preceding claims, wherein the said organic carboxylic acid is an aliphatic hydroxy-carboxylic acid.
5. An electrolyte as claimed in any one of the preceding claims, wherein the said organic carboxylic acid
is an aliphatic hydroxy di- ortri-carboxylic acid.
6. An electrolyte as claimed in any one of the preceding claims further comprising a non-ionogenic nitrogen-containing compound of the ethoxylated fatty amine type.
7. An electrolyte as claimed in claim 6, wherein the said nitrogen-containing compound is present in a concentration of from 0.3 to 2 ml/l.
8. An electrolyte as claimed in either of claims 6 and 7, wherein the said nitrogen-containing compound is that known commercially as "Stockomin".
9. The electrolyte of any of the above claims, in which the alkali gold (I) cyanide is potassium gold (I) cyanide and the nickel is added as nickel sulphate.
10. The electrolyte of Claim 9 containing from 1 to 4.5. g/l of potassium gold (I) cyanide, from 16 to 55 g/l nickel sulphate (NiS04) from 40 to 1 00'gil citric acid, about 35 to 40 g/l potassium hydroxide, and 0.2 to 3.0 g/l thiodiglycollic acid.
11. The electrolyte of Claim 10 in which the electrolyte contains from 2 to 3 g/l of potassium gold (I) cyanide, from 35 to 40 gil nickel sulphate (N iSO4). about 50 gil citric acid, from 35 to 40 gil of potassium hydroxide, and between 0.2 and 0.3 gil of thiodiglycollic acid.
12. An electrolyte as claimed in any of the preceding claims the pH whereof is between 3.5 and 4.2.
13. The electrolyte of any of the above claims, with the addition of a metal to modify colour.
14. The electrolyte of Claim 13 in which the metal is chosen from the group cobalt, iron and indium.
15. Electrolytes for electrodesposition of white gold, substantially as herein described.
16. A process for electrodepositing white gold using the electrolyte of any of the above claims, in which the bath is at a temperature between 40 and 60"C, the current density is between 0.5 and 3.0 A/dm2 and the movement of electrolyte relative to the cathode is between 4 and 20 cm/sec.
17. The process of Claim 16 in which the bath temperature is about 60"C, the current density about 1.5 Aidm2 and the movement of electrolyte relative to the cathode about 8 cm/sec.
18. A process for producing white gold coatings in which the electrolyte used is that claimed in any of claims 1 to 15.
19. Process for the electrodeposition of white gold, substantially as herein described.
20. Articles whenever electrolytically coated by the use of an electrolyte as claimed in any of claims 1 to 15.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19782855735 DE2855735A1 (en) | 1978-12-22 | 1978-12-22 | ELECTROLYTE FOR THE GALVANIC DEPOSITION OF WHITE GOLD ALLOYS AND ITS USE |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB2039532A true GB2039532A (en) | 1980-08-13 |
Family
ID=6058145
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB7944282A Withdrawn GB2039532A (en) | 1978-12-22 | 1979-12-21 | Electrolyte for the electrodeposition of white gold |
Country Status (4)
| Country | Link |
|---|---|
| JP (1) | JPS5594490A (en) |
| DE (1) | DE2855735A1 (en) |
| FR (1) | FR2444726A1 (en) |
| GB (1) | GB2039532A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4436595A (en) | 1981-06-05 | 1984-03-13 | Metal Surfaces, Inc. | Electroplating bath and method |
| US4670107A (en) * | 1986-03-05 | 1987-06-02 | Vanguard Research Associates, Inc. | Electrolyte solution and process for high speed gold plating |
| EP4245893A1 (en) | 2022-03-15 | 2023-09-20 | Université de Franche-Comté | Gold electroplating solution and its use for electrodepositing gold with an aged appearance |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4868121B2 (en) * | 2005-12-21 | 2012-02-01 | 学校法人早稲田大学 | Electroplating solution and method for forming amorphous gold-nickel alloy plating film |
-
1978
- 1978-12-22 DE DE19782855735 patent/DE2855735A1/en not_active Withdrawn
-
1979
- 1979-12-19 FR FR7931085A patent/FR2444726A1/en not_active Withdrawn
- 1979-12-21 JP JP16573179A patent/JPS5594490A/en active Pending
- 1979-12-21 GB GB7944282A patent/GB2039532A/en not_active Withdrawn
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4436595A (en) | 1981-06-05 | 1984-03-13 | Metal Surfaces, Inc. | Electroplating bath and method |
| US4670107A (en) * | 1986-03-05 | 1987-06-02 | Vanguard Research Associates, Inc. | Electrolyte solution and process for high speed gold plating |
| EP4245893A1 (en) | 2022-03-15 | 2023-09-20 | Université de Franche-Comté | Gold electroplating solution and its use for electrodepositing gold with an aged appearance |
| WO2023174871A1 (en) | 2022-03-15 | 2023-09-21 | Université de Franche-Comté | Gold electroplating solution and its use for electrodepositing gold with an aged appearance |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5594490A (en) | 1980-07-17 |
| DE2855735A1 (en) | 1980-07-03 |
| FR2444726A1 (en) | 1980-07-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US3475292A (en) | Gold plating bath and process | |
| US2905601A (en) | Electroplating bright gold | |
| US4076598A (en) | Method, electrolyte and additive for electroplating a cobalt brightened gold alloy | |
| JP2011520037A (en) | Improved copper-tin electrolyte and bronze layer deposition method | |
| US3902977A (en) | Gold plating solutions and method | |
| US4605474A (en) | Alkaline cyanide bath for electrolytic deposition of copper-tin-alloy coatings | |
| HUP0103906A2 (en) | Ductility agents for nickel-tungsten alloys | |
| US2176668A (en) | Silver plating process | |
| US2658032A (en) | Electrodeposition of bright copper-tin alloy | |
| JPH01149987A (en) | Tin-cobalt, tin-nickel or tin-lead binary alloy electroplating bath composition | |
| JPS63203790A (en) | Cyanide-free bright copper-zinc alloy electroplating bath | |
| US3440151A (en) | Electrodeposition of copper-tin alloys | |
| JPS6141999B2 (en) | ||
| US4048023A (en) | Electrodeposition of gold-palladium alloys | |
| GB2039532A (en) | Electrolyte for the electrodeposition of white gold | |
| US2435967A (en) | Bright alloy plating | |
| US3586611A (en) | Process for the electrolytic deposition of gold-copper-cadmium alloys | |
| EP0018752A1 (en) | Electrodeposit of a white gold alloy, its preparation and electroplating bath | |
| US4155817A (en) | Low free cyanide high purity silver electroplating bath and method | |
| US2876178A (en) | Electrodepositing copper | |
| US2793990A (en) | Electrodeposition of alloys containing copper and tin | |
| GB2086428A (en) | Hardened gold plating process | |
| JPH0321637B2 (en) | ||
| US4411744A (en) | Bath and process for high speed nickel electroplating | |
| EP0502229B1 (en) | Electroplating bath solution for zinc alloy and electro plated product using the same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |