US2602774A - Method of plating copper - Google Patents
Method of plating copper Download PDFInfo
- Publication number
- US2602774A US2602774A US26475A US2647548A US2602774A US 2602774 A US2602774 A US 2602774A US 26475 A US26475 A US 26475A US 2647548 A US2647548 A US 2647548A US 2602774 A US2602774 A US 2602774A
- Authority
- US
- United States
- Prior art keywords
- bath
- copper
- chloride
- electrolyte
- 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.)
- Expired - Lifetime
Links
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 title claims description 13
- 229910052802 copper Inorganic materials 0.000 title claims description 13
- 239000010949 copper Substances 0.000 title claims description 13
- 238000000034 method Methods 0.000 title claims description 6
- 238000007747 plating Methods 0.000 title description 4
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 claims description 15
- IPCRBOOJBPETMF-UHFFFAOYSA-N N-acetylthiourea Chemical compound CC(=O)NC(N)=S IPCRBOOJBPETMF-UHFFFAOYSA-N 0.000 claims description 4
- BQJTUDIVKSVBDU-UHFFFAOYSA-L copper;sulfuric acid;sulfate Chemical compound [Cu+2].OS(O)(=O)=O.[O-]S([O-])(=O)=O BQJTUDIVKSVBDU-UHFFFAOYSA-L 0.000 claims description 3
- 238000000151 deposition Methods 0.000 claims description 3
- 239000003792 electrolyte Substances 0.000 description 13
- 239000002253 acid Substances 0.000 description 9
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 8
- 238000005868 electrolysis reaction Methods 0.000 description 7
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- 239000011248 coating agent Substances 0.000 description 4
- 238000000576 coating method Methods 0.000 description 4
- ARUVKPQLZAKDPS-UHFFFAOYSA-L copper(II) sulfate Chemical compound [Cu+2].[O-][S+2]([O-])([O-])[O-] ARUVKPQLZAKDPS-UHFFFAOYSA-L 0.000 description 4
- -1 chloride anions Chemical class 0.000 description 3
- 238000003756 stirring Methods 0.000 description 3
- MIDXCONKKJTLDX-UHFFFAOYSA-N 3,5-dimethylcyclopentane-1,2-dione Chemical compound CC1CC(C)C(=O)C1=O MIDXCONKKJTLDX-UHFFFAOYSA-N 0.000 description 2
- XFXPMWWXUTWYJX-UHFFFAOYSA-N Cyanide Chemical compound N#[C-] XFXPMWWXUTWYJX-UHFFFAOYSA-N 0.000 description 2
- 229920001353 Dextrin Polymers 0.000 description 2
- 239000004375 Dextrin Substances 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 2
- 238000013019 agitation Methods 0.000 description 2
- 238000007664 blowing Methods 0.000 description 2
- 235000013736 caramel Nutrition 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 229910000365 copper sulfate Inorganic materials 0.000 description 2
- 235000019425 dextrin Nutrition 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 239000004615 ingredient Substances 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 239000002932 luster Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 235000013379 molasses Nutrition 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- 241000054822 Lycaena cupreus Species 0.000 description 1
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Natural products NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 125000000218 acetic acid group Chemical group C(C)(=O)* 0.000 description 1
- UMGDCJDMYOKAJW-UHFFFAOYSA-N aminothiocarboxamide Natural products NC(N)=S UMGDCJDMYOKAJW-UHFFFAOYSA-N 0.000 description 1
- 150000001450 anions Chemical class 0.000 description 1
- 238000005282 brightening Methods 0.000 description 1
- KXZJHVJKXJLBKO-UHFFFAOYSA-N chembl1408157 Chemical compound N=1C2=CC=CC=C2C(C(=O)O)=CC=1C1=CC=C(O)C=C1 KXZJHVJKXJLBKO-UHFFFAOYSA-N 0.000 description 1
- 150000001805 chlorine compounds Chemical class 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000011651 chromium Substances 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000005187 foaming Methods 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 239000010865 sewage Substances 0.000 description 1
- 229910000029 sodium carbonate Inorganic materials 0.000 description 1
- 229940067741 sodium octyl sulfate Drugs 0.000 description 1
- WFRKJMRGXGWHBM-UHFFFAOYSA-M sodium;octyl sulfate Chemical compound [Na+].CCCCCCCCOS([O-])(=O)=O WFRKJMRGXGWHBM-UHFFFAOYSA-M 0.000 description 1
- 239000000080 wetting agent Substances 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
- 229910052725 zinc Inorganic materials 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
- C25D3/38—Electroplating: Baths therefor from solutions of copper
Definitions
- the essence of the inventlonthus consistsyin providing an electrolyte for acid copper plating in which the.chloric le. anion content ranges from 0.001 to 0.0115 gram per liter.
- the predominant ingredients of: the bath preferred for the electrolysis are copper sulphate andsuliuri'c acid.
- the invention thus consists in an electrolytic bath which contains 1 to 275 grJl. copper sulfate 20 to grJl. sulfuric acid 0.001 to 0.015 gr./l. chloride anion 0 to 1.0 gr./l. caramel. dextrin and/or molasses 0.005 to 0.05 gr./l. of acetyl thiourea
- the articles to be plated are advantageously subjected to a preliminary treatment prior to the coating proper. For this purpose they are cleaned with an alkaline cleaner, dipped into acid in order to remove any rust, nuetralized and then rinsed in water. It is also preferable to first apply a thin copper coating from a cyanide both.
- such a bath may contain from 3 to 5 ounces of copper metal per gallon, 1% to 3 ounces of free sodium cyanide and from 2 to 8 ounces of sodium carbonate. Plating with this bath for from 3 to 4 minutes is suilicient. After this flash plating the article is washed to remove the cyanide.
- the temperature of the bath is preferably maintained at between 80 and 100 F.
- the electric current should have a voltage of from 2.5 to 6 volts and a density of from 40 to 200 amps. per square foot.
- Example I An electrolyte was used having the following composition:
- the coating obtained in this instance was extremely smooth and uniform and had a high luster.
- the bath did not show any turbidity even after a use of several weeks.
- the tolerance for impurities for a bath of this invention is considerably increasedinparticular for iron, zinc, chromium and nickel.
- an iron content of 0.25 gr/l. is harmful and impairs the operation.
- a chloride anion content is set forth in this specification several grams per liter may be present in the electrolyte and the operation will still be satisfactory.
- Example II 200 gr./l. copper sulfate 50 g g/l. sulfuric acid 0.005 gr./l. chloride anion
- the process with this electrolyte was carried out under the same conditions as were used in connection with Example I with the exception 4 that agitation of the electrolyte was effected by moving the cathode instead of introducing air. The same favorable results were obtained.
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)
- Electrolytic Production Of Metals (AREA)
Description
Patented July 8, 1952 JnhrrEcBaavcr. Osborn, Ohio Nonrawlng. Application May 11, 1948, Serial No. 26,475
high luster'so that hurling of the surface is not necessary.
It is another object of this invention to provide a bright copper deposit by electrolysis from an acid. bath with which operation can be satisfacinfily-continued over a lonaneriod of time without. noticeable, deterioration oi the bath; or impairmentoi the coating.
It is still another object 01 this invention to provide a bright copper deposit by electrolysis of an acid bath with which. an electric current of high density may be used.
It isstill another object of thislnvention to provide a bright copper deposit by electrolysis of an acid bath does not requirefrequent renewal. of the electrolyte and. discarding of the bath used.
It is still another object. oi. this invention to provide a bright copper deposit. by electrolysis using, an acid bath whichdoes notbecometurbid after some time so that a filtering stendoes not have to be inserted from time to time.
It is still another object of this invention to provide a bright copper deposit by electrolysis using an acid bath which has a highly increased tolerance for impurities.
It has been found by the applicant during comprehensive research work that, while electrolytes based on a mixture of copper sulphate and sulfuric acid operate satisfactorily in the beginning, the deposits become less and less uniform as the operation continues. This phenomenon was even noticed although the proportions of the ingredients oi the bath were constantly kept at the same level. As a consequence of the disadvantage just described the electrolyte had to be discarded at frequent intervals and replaced by a new one.
After a great many experiments it was discovered that the change of the content of chloride anion is responsible for such unsatisfactory operation.
After this discovery it was then found out that 2 the electrolytes when first usediingthe hes had a very low content of chloride anions which were present in the form of. acontamination but that this chloride content became gradually depleted. This was when the opora km s artedt become unsatisfactory.
Further studies of the problem revealed that it the chloride anion content of the electrolyte is controlled, so as to bring it within a range of from 0.001 to 0.015 gram per liter of electrolyte all these disadvantages are. overcome. A bath thus composed yields deposits of the desired properties for a very considerable, period oftime.
The essence of the inventlonthus consistsyin providing an electrolyte for acid copper plating in which the.chloric le. anion content ranges from 0.001 to 0.0115 gram per liter.
As. has been mentioned above the predominant ingredients of: the bath preferred for the electrolysis are copper sulphate andsuliuri'c acid.
It is advantageous to add a brightening agent to the elecrtolyte; derivatives of; thiourca. ha been found especial y suitable. to: this purpose. and in particular acetyl thlourea has yielded excellent results.
It is also advantageous, though cutionahtaadd an agent which permits the use of an electric current of high density. .nentrim molasses. and caramel are excellenttor Sometimes it is also to add ,a .1 flung a ent; so i l ryl sulfateandsodium ocit'lsidfate are preferred therefor.
The invention thus consists in an electrolytic bath which contains 1 to 275 grJl. copper sulfate 20 to grJl. sulfuric acid 0.001 to 0.015 gr./l. chloride anion 0 to 1.0 gr./l. caramel. dextrin and/or molasses 0.005 to 0.05 gr./l. of acetyl thiourea The articles to be plated are advantageously subjected to a preliminary treatment prior to the coating proper. For this purpose they are cleaned with an alkaline cleaner, dipped into acid in order to remove any rust, nuetralized and then rinsed in water. It is also preferable to first apply a thin copper coating from a cyanide both. such a bath may contain from 3 to 5 ounces of copper metal per gallon, 1% to 3 ounces of free sodium cyanide and from 2 to 8 ounces of sodium carbonate. Plating with this bath for from 3 to 4 minutes is suilicient. After this flash plating the article is washed to remove the cyanide.
It is furthermore advantageous to agitate the electrolyte during electrolysis. This may be carried out either by moving the cathode or by stirring the electrolyte, the latter being preferred. In particular has it been found satisfactory to effect stirring by blowing air through the bath. If stirring is carried out this way, however, it is advisable to restrict the quantity of the wetting agent to a minimum or omit it entirely, because otherwise excessive foaming takes place which impairs the operation.
The temperature of the bath is preferably maintained at between 80 and 100 F. The electric current should have a voltage of from 2.5 to 6 volts and a density of from 40 to 200 amps. per square foot.
In the following, two examples are given for the purpose of illustrating my invention:
Example I An electrolyte was used having the following composition:
35 i gin/i. CuSOefiHaO Bligh/l. sulfuric acid 0.005gr./l. chloride anion 0.10 gr./1. dextrin 0.015 gr./l. acetyl thiourea 0.02 gr./l. sodium octyl sulfate The bath had a temperature of 95 F. Agitation was carried out by blowing air through the bath. vThe electric current had a density of 100 amps.
per sq. ft. and a voltage of 4.5 volts.
The coating obtained in this instance was extremely smooth and uniform and had a high luster. The bath did not show any turbidity even after a use of several weeks.
The tolerance for impurities for a bath of this invention is considerably increasedinparticular for iron, zinc, chromium and nickel. For instance, without the presence of chloride anions, an iron content of 0.25 gr/l. is harmful and impairs the operation. With a chloride anion content is set forth in this specification several grams per liter may be present in the electrolyte and the operation will still be satisfactory.
Example II 200 gr./l. copper sulfate 50 g g/l. sulfuric acid 0.005 gr./l. chloride anion The process with this electrolyte was carried out under the same conditions as were used in connection with Example I with the exception 4 that agitation of the electrolyte was effected by moving the cathode instead of introducing air. The same favorable results were obtained.
It will be understood that while there have been described herein certain specific embodiments of my invention, it is not intended thereby to have it limited to the details given in view of the fact that this invention is susceptible to various modifications and changes which come within the spirit oi the disclosure and the scope of the appended claims.
I claim:
1. In a method of electrolytically depositing copper from a copper sulfate-sulphuric acid bath containing acetyl thiourea in an amount of from about 0.005 to 0.05 gm./l. and chloride anion in an amount of from about 0.001 to 0.015 gm.'/l., the step of maintaining the chloride anion concentration at a constant value within the range of about 0.001 to 0.015 gm./l. by addition of a chloride.
2. In a method of electrolytically depositing copper from a copper sulfate-sulphuric acid bath containing a thiourea compound in an amount of from about 0.005 to 0.05 gm./l. and chloride anion in an amount of from about 0.001 to 0.015 gm./1., the step of maintaining the chloride anion concentration at a constant value within the range of about 0.001 to 0.015 gm./l. by addition of a chloride.
JOHN F. BEAVER.
REFERENCES drum The following references are of record in the pp. 457-458. I
Buswell: Chemistry of Water and Sewage Treatment, 1928,,pp..74-76.
Operating Manual Daybrite Acid Copper 'Proc ess, pp. 2-3.
Claims (1)
1. IN A METHOD OF ELECTROLYTICALLY DEPOSITING COPPER FROM A COPPER SULFATE-SULPHURIC ACID BATH CONTAINING ACETYL THIOUREA IN AN AMOUNT OF FROM ABOUT 0.005 TO 0.05 GM./L. AND CHLORIDE ANION IN AN AMOUNT OF FROM ABOUT 0.001 TO 0.015 GM./1., THE STEP OF MAINTAINING THE CHLORIDE ANION CONCENTRATION AT A CONSTANT VALUE WITHIN THE RANGE OF ABOUT 0.001 TO 0.015 GM./L. BY ADDITION OF A CHLORIDE.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US24253D USRE24253E (en) | 1948-05-11 | Method of producing a composite liquid | |
| US26475A US2602774A (en) | 1948-05-11 | 1948-05-11 | Method of plating copper |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US26475A US2602774A (en) | 1948-05-11 | 1948-05-11 | Method of plating copper |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2602774A true US2602774A (en) | 1952-07-08 |
Family
ID=21832033
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US24253D Expired USRE24253E (en) | 1948-05-11 | Method of producing a composite liquid | |
| US26475A Expired - Lifetime US2602774A (en) | 1948-05-11 | 1948-05-11 | Method of plating copper |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US24253D Expired USRE24253E (en) | 1948-05-11 | Method of producing a composite liquid |
Country Status (1)
| Country | Link |
|---|---|
| US (2) | US2602774A (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2707166A (en) * | 1952-05-26 | 1955-04-26 | Udylite Corp | Electrodeposition of copper from an acid bath |
| US2707167A (en) * | 1952-05-26 | 1955-04-26 | Udylite Corp | Electrodeposition of copper from an acid bath |
| US2738318A (en) * | 1954-12-28 | 1956-03-13 | Udylite Res Corp | Electrodeposition of copper from an acid bath |
| US2762762A (en) * | 1953-02-27 | 1956-09-11 | Rca Corp | Method for electroforming a copper article |
| US2931760A (en) * | 1957-09-25 | 1960-04-05 | Leon R Westbrook | Acid copper plating |
| DE1097231B (en) * | 1957-09-11 | 1961-01-12 | Westinghouse Electric Corp | Acid galvanic copper bath |
| US3769179A (en) * | 1972-01-19 | 1973-10-30 | Kewanee Oil Co | Copper plating process for printed circuits |
| US4474649A (en) * | 1982-06-21 | 1984-10-02 | Asarco Incorporated | Method of thiourea addition of electrolytic solutions useful for copper refining |
| US5181770A (en) * | 1989-04-19 | 1993-01-26 | Olin Corporation | Surface topography optimization through control of chloride concentration in electroformed copper foil |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3220897A (en) * | 1961-02-13 | 1965-11-30 | Esther S Conley | Conducting element and method |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US964096A (en) * | 1906-03-19 | 1910-07-12 | Thomas A Edison | Process for electroplating. |
| US2355070A (en) * | 1937-07-03 | 1944-08-08 | Little Inc A | Electrolytic deposition of metal |
| US2391289A (en) * | 1941-09-15 | 1945-12-18 | Jr John F Beaver | Bright copper plating |
| US2462870A (en) * | 1942-07-09 | 1949-03-01 | Gen Motors Corp | Electrodeposition of copper |
-
0
- US US24253D patent/USRE24253E/en not_active Expired
-
1948
- 1948-05-11 US US26475A patent/US2602774A/en not_active Expired - Lifetime
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US964096A (en) * | 1906-03-19 | 1910-07-12 | Thomas A Edison | Process for electroplating. |
| US2355070A (en) * | 1937-07-03 | 1944-08-08 | Little Inc A | Electrolytic deposition of metal |
| US2391289A (en) * | 1941-09-15 | 1945-12-18 | Jr John F Beaver | Bright copper plating |
| US2462870A (en) * | 1942-07-09 | 1949-03-01 | Gen Motors Corp | Electrodeposition of copper |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2707166A (en) * | 1952-05-26 | 1955-04-26 | Udylite Corp | Electrodeposition of copper from an acid bath |
| US2707167A (en) * | 1952-05-26 | 1955-04-26 | Udylite Corp | Electrodeposition of copper from an acid bath |
| US2762762A (en) * | 1953-02-27 | 1956-09-11 | Rca Corp | Method for electroforming a copper article |
| US2738318A (en) * | 1954-12-28 | 1956-03-13 | Udylite Res Corp | Electrodeposition of copper from an acid bath |
| DE1097231B (en) * | 1957-09-11 | 1961-01-12 | Westinghouse Electric Corp | Acid galvanic copper bath |
| US2931760A (en) * | 1957-09-25 | 1960-04-05 | Leon R Westbrook | Acid copper plating |
| US3769179A (en) * | 1972-01-19 | 1973-10-30 | Kewanee Oil Co | Copper plating process for printed circuits |
| US4474649A (en) * | 1982-06-21 | 1984-10-02 | Asarco Incorporated | Method of thiourea addition of electrolytic solutions useful for copper refining |
| US5181770A (en) * | 1989-04-19 | 1993-01-26 | Olin Corporation | Surface topography optimization through control of chloride concentration in electroformed copper foil |
Also Published As
| Publication number | Publication date |
|---|---|
| USRE24253E (en) | 1956-12-11 |
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