US2563360A - Electrodeposition of copper - Google Patents
Electrodeposition of copper Download PDFInfo
- Publication number
- US2563360A US2563360A US717333A US71733346A US2563360A US 2563360 A US2563360 A US 2563360A US 717333 A US717333 A US 717333A US 71733346 A US71733346 A US 71733346A US 2563360 A US2563360 A US 2563360A
- Authority
- US
- United States
- Prior art keywords
- copper
- grams
- thiourea
- per liter
- 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 group [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 title description 24
- 229910052802 copper Inorganic materials 0.000 title description 24
- 239000010949 copper Substances 0.000 title description 24
- 238000004070 electrodeposition Methods 0.000 title description 11
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 31
- ARUVKPQLZAKDPS-UHFFFAOYSA-L copper(II) sulfate Chemical compound [Cu+2].[O-][S+2]([O-])([O-])[O-] ARUVKPQLZAKDPS-UHFFFAOYSA-L 0.000 claims description 28
- 239000001117 sulphuric acid Substances 0.000 claims description 23
- 235000011149 sulphuric acid Nutrition 0.000 claims description 23
- 239000003792 electrolyte Substances 0.000 claims description 12
- 150000001875 compounds Chemical class 0.000 claims description 10
- 239000011260 aqueous acid Substances 0.000 claims description 7
- UMGDCJDMYOKAJW-UHFFFAOYSA-N thiourea Chemical compound NC(N)=S UMGDCJDMYOKAJW-UHFFFAOYSA-N 0.000 description 58
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Natural products NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 29
- 238000007792 addition Methods 0.000 description 16
- 239000003795 chemical substances by application Substances 0.000 description 16
- 239000000243 solution Substances 0.000 description 15
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 8
- 239000002253 acid Substances 0.000 description 8
- 238000007747 plating Methods 0.000 description 8
- 239000000080 wetting agent Substances 0.000 description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 7
- 229910052751 metal Inorganic materials 0.000 description 6
- 239000002184 metal Substances 0.000 description 6
- 239000007864 aqueous solution Substances 0.000 description 5
- 238000005282 brightening Methods 0.000 description 5
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 4
- 125000003118 aryl group Chemical group 0.000 description 4
- 125000004432 carbon atom Chemical group C* 0.000 description 4
- 229910000365 copper sulfate Inorganic materials 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 150000002739 metals Chemical class 0.000 description 4
- 229910052759 nickel Inorganic materials 0.000 description 4
- 150000003839 salts Chemical class 0.000 description 4
- DBMJMQXJHONAFJ-UHFFFAOYSA-M Sodium laurylsulphate Chemical compound [Na+].CCCCCCCCCCCCOS([O-])(=O)=O DBMJMQXJHONAFJ-UHFFFAOYSA-M 0.000 description 3
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 3
- HTKFORQRBXIQHD-UHFFFAOYSA-N allylthiourea Chemical compound NC(=S)NCC=C HTKFORQRBXIQHD-UHFFFAOYSA-N 0.000 description 3
- 229910052793 cadmium Inorganic materials 0.000 description 3
- BDOSMKKIYDKNTQ-UHFFFAOYSA-N cadmium atom Chemical compound [Cd] BDOSMKKIYDKNTQ-UHFFFAOYSA-N 0.000 description 3
- QCUOBSQYDGUHHT-UHFFFAOYSA-L cadmium sulfate Chemical compound [Cd+2].[O-]S([O-])(=O)=O QCUOBSQYDGUHHT-UHFFFAOYSA-L 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 3
- -1 for example Chemical class 0.000 description 3
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 3
- RUFPHBVGCFYCNW-UHFFFAOYSA-N 1-naphthylamine Chemical compound C1=CC=C2C(N)=CC=CC2=C1 RUFPHBVGCFYCNW-UHFFFAOYSA-N 0.000 description 2
- ZGZXYZZHXXTTJN-UHFFFAOYSA-N 2,3-dichlorobenzenesulfonic acid Chemical compound OS(=O)(=O)C1=CC=CC(Cl)=C1Cl ZGZXYZZHXXTTJN-UHFFFAOYSA-N 0.000 description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical group N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- 239000005864 Sulphur Substances 0.000 description 2
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 2
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 2
- JXLHNMVSKXFWAO-UHFFFAOYSA-N azane;7-fluoro-2,1,3-benzoxadiazole-4-sulfonic acid Chemical compound N.OS(=O)(=O)C1=CC=C(F)C2=NON=C12 JXLHNMVSKXFWAO-UHFFFAOYSA-N 0.000 description 2
- 229910017052 cobalt Inorganic materials 0.000 description 2
- 239000010941 cobalt Substances 0.000 description 2
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 2
- 239000000470 constituent Substances 0.000 description 2
- 150000002170 ethers Chemical group 0.000 description 2
- BRWIZMBXBAOCCF-UHFFFAOYSA-N hydrazinecarbothioamide Chemical compound NNC(N)=S BRWIZMBXBAOCCF-UHFFFAOYSA-N 0.000 description 2
- 125000001183 hydrocarbyl group Chemical group 0.000 description 2
- 150000002500 ions Chemical class 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 229910000159 nickel phosphate Inorganic materials 0.000 description 2
- JOCJYBPHESYFOK-UHFFFAOYSA-K nickel(3+);phosphate Chemical compound [Ni+3].[O-]P([O-])([O-])=O JOCJYBPHESYFOK-UHFFFAOYSA-K 0.000 description 2
- 125000004433 nitrogen atom Chemical group N* 0.000 description 2
- DGSDBJMBHCQYGN-UHFFFAOYSA-M sodium;2-ethylhexyl sulfate Chemical compound [Na+].CCCCC(CC)COS([O-])(=O)=O DGSDBJMBHCQYGN-UHFFFAOYSA-M 0.000 description 2
- 150000003585 thioureas Chemical class 0.000 description 2
- GPRLSGONYQIRFK-MNYXATJNSA-N triton Chemical compound [3H+] GPRLSGONYQIRFK-MNYXATJNSA-N 0.000 description 2
- 229910052725 zinc Inorganic materials 0.000 description 2
- 239000011701 zinc Substances 0.000 description 2
- LBLYYCQCTBFVLH-UHFFFAOYSA-N 2-Methylbenzenesulfonic acid Chemical compound CC1=CC=CC=C1S(O)(=O)=O LBLYYCQCTBFVLH-UHFFFAOYSA-N 0.000 description 1
- PITMOJXAHYPVLG-UHFFFAOYSA-N 2-acetyloxybenzoic acid;n-(4-ethoxyphenyl)acetamide;1,3,7-trimethylpurine-2,6-dione Chemical compound CCOC1=CC=C(NC(C)=O)C=C1.CC(=O)OC1=CC=CC=C1C(O)=O.CN1C(=O)N(C)C(=O)C2=C1N=CN2C PITMOJXAHYPVLG-UHFFFAOYSA-N 0.000 description 1
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical class S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- 150000001298 alcohols Chemical class 0.000 description 1
- 229960001748 allylthiourea Drugs 0.000 description 1
- 125000003277 amino group Chemical group 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- BFNBIHQBYMNNAN-UHFFFAOYSA-N ammonium sulfate Chemical compound N.N.OS(O)(=O)=O BFNBIHQBYMNNAN-UHFFFAOYSA-N 0.000 description 1
- 229910052921 ammonium sulfate Inorganic materials 0.000 description 1
- 239000001166 ammonium sulphate Substances 0.000 description 1
- 235000011130 ammonium sulphate Nutrition 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- BHUKLPWMSMTPRJ-UHFFFAOYSA-L benzene-1,2-disulfonate;nickel(2+) Chemical compound [Ni+2].[O-]S(=O)(=O)C1=CC=CC=C1S([O-])(=O)=O BHUKLPWMSMTPRJ-UHFFFAOYSA-L 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000011651 chromium Substances 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- JZCCFEFSEZPSOG-UHFFFAOYSA-L copper(II) sulfate pentahydrate Chemical compound O.O.O.O.O.[Cu+2].[O-]S([O-])(=O)=O JZCCFEFSEZPSOG-UHFFFAOYSA-L 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- REQPQFUJGGOFQL-UHFFFAOYSA-N dimethylcarbamothioyl n,n-dimethylcarbamodithioate Chemical compound CN(C)C(=S)SC(=S)N(C)C REQPQFUJGGOFQL-UHFFFAOYSA-N 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 150000002540 isothiocyanates Chemical class 0.000 description 1
- 239000011777 magnesium Substances 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 230000003389 potentiating effect Effects 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 235000019333 sodium laurylsulphate Nutrition 0.000 description 1
- 159000000000 sodium salts Chemical class 0.000 description 1
- ZKBBQUFQDGOTBZ-UHFFFAOYSA-N sodium;1,2,3-tri(propan-2-yl)naphthalene Chemical compound [Na].C1=CC=C2C(C(C)C)=C(C(C)C)C(C(C)C)=CC2=C1 ZKBBQUFQDGOTBZ-UHFFFAOYSA-N 0.000 description 1
- 125000001273 sulfonato group Chemical group [O-]S(*)(=O)=O 0.000 description 1
- BDHFUVZGWQCTTF-UHFFFAOYSA-N sulfonic acid Chemical compound OS(=O)=O BDHFUVZGWQCTTF-UHFFFAOYSA-N 0.000 description 1
- 229910021653 sulphate ion Inorganic materials 0.000 description 1
- YUKQRDCYNOVPGJ-UHFFFAOYSA-N thioacetamide Chemical compound CC(N)=S YUKQRDCYNOVPGJ-UHFFFAOYSA-N 0.000 description 1
- DLFVBJFMPXGRIB-UHFFFAOYSA-N thioacetamide Natural products CC(N)=O DLFVBJFMPXGRIB-UHFFFAOYSA-N 0.000 description 1
- NBOMNTLFRHMDEZ-UHFFFAOYSA-N thiosalicylic acid Chemical compound OC(=O)C1=CC=CC=C1S NBOMNTLFRHMDEZ-UHFFFAOYSA-N 0.000 description 1
- 229940103494 thiosalicylic acid Drugs 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 invention relates to the electrodeposition of copper from acid baths and has for its object the formation of deposits which have a greater degree of smoothness or brilliance than is ordinarily obtained as well as deposits which are characterized by remarkable buifability or capability of being buffed or colored by the usual buffing instrumentalities, when necessary.
- the invention is based upon the use of certain addition agents in novel relationship and the determination of the factors affecting and action of these agents to produce most satisfactory results.
- control agents may be of either or both, metallic and organic non-metallic character.
- metallic type the metals cadminum, zinc, cobalt and nickel have somewhat similar effects. They may be added in the form of salts, for example, sul phates. Cadminum sulphate, in amounts up to about 75 grams per liter of bath, seems to enhance the brightening effect in combination with thiourea. It also improves the deposit as to softness and texture. When thus present in the bath the metals are deposited along with the copper in small proportions. With cadmium sulphate, for example, we have found up to five hundredths of one percent of cadmium in the deposit.
- nickel for example, very satisfactory results have been obtained by the use of nickel phosphate in amounts, for example, of about 35 grams per liter, a small amount of phosphoric acid being added also.
- non-metallic control agents we have found the most effective to be organic compounds of the class generally known as surface tension reducing or wetting agents.
- wetting agents found suitable are aromatic sulphonates and a considerable number are on the market under various trade names.
- those that are useful in the acid copper sulphate bath in combination with the primary addition agents the following have been found especially beneficial:
- Triton 720i Neomerpin and Tergitol 08
- Triton 720i is a sulphonated ether containing a branch chain and an aromatic nucleus. More specifically it is one or more compounds of the formulawherein Ar is a hydrocarbon substituted aromatic nucleus, M is a metal of the group consisting of sodium, potassium, calcium and magnesium, or is an ammonia or amine group, n is any whole number from three to six and the hydrocarbon substituent of the aryl group has carbon atoms within the range of four to twelve. Attention is also directed to U. S. Patent 2,115,192 which discloses this known wetting agent. It is sold generally.
- Tergitol 08 is essentially the sulfate ester of secondary higher alcohols.
- the neomerpin compounds are alkyl naphthalene sulphonic acids and sodium salts thereof.
- organic sulphonates that have been satisfactorily used along with thiourea in the acid coopper bath, particularly in combination with the metallic additions, are di-chloro-benzene sulphonic acid, nickel benzene disulphonate, toluene sulphonic acid, naphthylamine d sulphonic acid and sodium tri-isopropyl naphthalene sulphonate. These are representative of a considerable variety of aromatic sulphonates that possess similar properties and may be eiTectively employed.
- Other wetting agents well known in the commercial field such as, for example, Duponol, may be used.
- Duponol is essentially sodium lauryl sulfate. Where the wetting agent is added by weight, amounts of 0.01 to grams per liter may be used, larger amounts being generally associated with higher content of the primary addition agent.
- agents that have the function of increasing the bright-plating range For example, ammonium sulphate in amounts of 1-100 grams per liter has been found effective.
- the primary addition agent above referred to as active-sulphuraqmtaining and represented typically by thiourea is not limited to thiourea alone.
- the class is characterized generally as containing a bivalent sulphur atom both bonds of which are directly connected to a carbon atom together with one or more nitrogen atoms also directly connected to the carbon atom. It is understood, of course, that in this group of compounds the double bond may in some cases exist or alternate between the sulphur or nitrogen atom and the carbon atom.
- Thiosinamine (allyl thiourea) and thiosemicarbazide may be mentioned as additional examples of the thioureas.
- the water soluble mercaptans for example B-dithioglycoll and thiosalicylic acid have also a brightening eifect.
- aqueous solutions containing 125 to 250 grams per liter of the technical copper sulphate ordinarily supplied for plating and 5 to 100 grams of sulphuric acid are well known and thiourea is effective over the entire range with suitable adjustment as to plating conditions.
- the composition of the bath with reference to the content of copper sulphate and sulphuric acid is not critical within operating limits. It is essential, of course, that materials should not be added to the bath which would precipitate or destroy the brightening effect of the brightening agent. As an illustration of this it is pointed out that the presence of chloride ions to be avoided as much as possible since they tend to precipitate thiourea with consequent loss of brightness.
- the temperature of the bath for best results may vary from relatively low limits, for example,
- the baths described enable plated deposits of copper, or chiefly of copper, to be obtained which, within a certain medium range of conditions, are truly brilliant. However, even if the conditions are not so accurately maintained as to produce an entirely brilliant deposit or uniform brightness over the entire area, still the deposits are characterized by extreme fineness of crystal structure and remarkable case of buifing to brilliance as compared with copper deposits from the ordinary acid copper baths.
- the invention is therefore special utility in the plating of objects of irregular contour on which a bright surface is required, as where bright deposits of nickel or chromium are to be later applied. Furthermore, by reason of the reduction in the amount and severity of the bufling operation where such may be necessary, the requirements of labor, equipment, and bufling materials are greatly reduced and the danger of buifing through the coating is substantially eliminated.
- the method of cathodically depositing copper in a form having a substantial degree of brightness comprising passing current through a bath consisting essentially of an aqueous solution of copper sulphate, free sulphuric acid and a thiourea in amount between 0.002 and 5 grams per liter of solution.
- An electrolyte for the electrodeposition of copper in bright or semi-bright form consisting essentially of an aqueous solution of copper sulphate, sulphuric acid, thiourea and cadmium sluphate in substantially the following proportions, per liter:
- An electrolyte for electrodepositing copper consisting essentially of an aqueous acid solution of copper sulphate and sulphuric acid and having dissolved therein a thiourea and an organic sulphonate wetting agent, said thiourea having a concentration in said solution of 0.002-5 grams per liter, and the wetting agent a concentration of 0.01-5 grams per liter.
- An electrolyte for electrodeposition of copper in bright or semi-bright form which consists essentially of an aqueous solution of copper sulphate and sulphuric acid to which has been added, per liter of solution, 0.002-5 grams of thiourea.
- An electrolyte for electrodeposition of copper in bright or semi-bright form which consists essentially of an aqueous solution of copper sulphate and sulphuric acid to which has been added, per liter of solution, 0.002-5 grams of thiourea and 10-75 grams of a salt of a metal of the class consisting of cadmium, zinc, nickel and cobalt.
- An electrolyte for electrodeposition of copper in bright or semi-bright form which consists essentially of an aqueous copper sulphate solution containing free sulphuric acid and to which has been added 0.01-0.1 gram of thiourea per liter of solution.
- An electrolyte for the electrodeposition of copper consisting essentially of an aqueous acid solution of copper sulfate, sulfuric acid, and thiourea, the copper sulfate being present in an amount within the range of to 250 grams per liter, the sulfuric acid within the range of 10 to 50 grams per liter and the thiourea within the range of 0.002 to 5 grams per liter.
- An electrolyte for the electrodeposition of copper consisting essentially of an aqueous acid solution of copper sulfate, sulfuric acid and thiourea, the copper sulfate being present in an amount within the range of approximately 125 to 250 grams per liter, the sulfuric acid within the range of approximately 10 to 50 grams per liter and thiourea within the range of 0.01 to 0.1 gram per liter.
- An electrolyte for the electrodeposition of copper consisting essentially of an aqueous acid solution of copper sulphate and free sulphuric acid to which has been added a compound having the nucleus the copper sulphate being present within the range of approximately 125 to 250 grams per liter, the sulphuric acid within the range of approximately 10 to 50 grams per liter and the compound having said nucleus being present within the range of approximately 0.002 to 5 grams per liter.
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)
Description
Patented Aug. 7, 1951 UNITED STATES PATENT OFFICE ELECTRODEPOSITION OF COPPER William M. Phillips, Birmingham, and Frank L. Clifton, Detroit, Mich., assignors to General Motors Corporation, Detroit, Mich., a corporation of Delaware 12 Claims.
This application is a continuation-in-part of our copending application Serial No. 395,004, filed May 24, 1941.
The invention relates to the electrodeposition of copper from acid baths and has for its object the formation of deposits which have a greater degree of smoothness or brilliance than is ordinarily obtained as well as deposits which are characterized by remarkable buifability or capability of being buffed or colored by the usual buffing instrumentalities, when necessary.
The invention is based upon the use of certain addition agents in novel relationship and the determination of the factors affecting and action of these agents to produce most satisfactory results.
In accordance with the present invention it is proposed to employ copper plating baths of the usual sulphuric acid type in which the copper is present in the form of copper sulphate. To such bath is added as a primary addition agent a very small proportion of an organic brighten ing and structure-controlling agent which may becharacterized by the presence of active sulphur, a thiourea being a typical example. In a standard acid copper bath containing, for example. 250 grams of copper sulphate, CuSO4.5H2O, and grams more or less of sulphuric acid per liter, the addition of as little as 0.002 gram per liter of thiourea will bring about a noticeable improvement in brightness and structure. Much larger additions up to above five grams per liter of thiourea have been successfully employed, but the larger amounts are unnecessary for best results and therefore it is generally preferred to use in the neighborhood of 0.01 to 0.1 gram per 1 er.
Further improvement in the uniformity of distribution of the effect of the primary or activesulphur containing addition agents and in the range if plating conditions, such as current density, as well as the characteristics of the deposit may be obtained by the use of further additions of what we may term control agents. These may be of either or both, metallic and organic non-metallic character. Of the metallic type, the metals cadminum, zinc, cobalt and nickel have somewhat similar effects. They may be added in the form of salts, for example, sul phates. Cadminum sulphate, in amounts up to about 75 grams per liter of bath, seems to enhance the brightening effect in combination with thiourea. It also improves the deposit as to softness and texture. When thus present in the bath the metals are deposited along with the copper in small proportions. With cadmium sulphate, for example, we have found up to five hundredths of one percent of cadmium in the deposit.
Other salts than the sulphates may be employed if compatible with the bath and, in the case of some of the metals named, may be preferable to the sulphates. With nickel, for example, very satisfactory results have been obtained by the use of nickel phosphate in amounts, for example, of about 35 grams per liter, a small amount of phosphoric acid being added also.
01 the non-metallic control agents we have found the most effective to be organic compounds of the class generally known as surface tension reducing or wetting agents. Many of the wetting agents found suitable are aromatic sulphonates and a considerable number are on the market under various trade names. Among those that are useful in the acid copper sulphate bath in combination with the primary addition agents, the following have been found especially beneficial:
"IIritOn 720i) Neomerpin and Tergitol 08 From the standpoint of cost, results and complete compatability with the acid copper bath the Triton 720 has proven highly satisfactory. It is a sulphonated ether containing a branch chain and an aromatic nucleus. More specifically it is one or more compounds of the formulawherein Ar is a hydrocarbon substituted aromatic nucleus, M is a metal of the group consisting of sodium, potassium, calcium and magnesium, or is an ammonia or amine group, n is any whole number from three to six and the hydrocarbon substituent of the aryl group has carbon atoms within the range of four to twelve. Attention is also directed to U. S. Patent 2,115,192 which discloses this known wetting agent. It is sold generally. in the form of an aqueous paste capable of being poured or measured by volume and, since the amounts to be used are not critical, .the paste may be added by volume, one c. c. corresponding to approximately one gram of other like agents. Tergitol 08 is essentially the sulfate ester of secondary higher alcohols. The neomerpin compounds are alkyl naphthalene sulphonic acids and sodium salts thereof.
Other organic sulphonates that have been satisfactorily used along with thiourea in the acid coopper bath, particularly in combination with the metallic additions, are di-chloro-benzene sulphonic acid, nickel benzene disulphonate, toluene sulphonic acid, naphthylamine d sulphonic acid and sodium tri-isopropyl naphthalene sulphonate. These are representative of a considerable variety of aromatic sulphonates that possess similar properties and may be eiTectively employed. Other wetting agents well known in the commercial field such as, for example, Duponol, may be used. Duponol is essentially sodium lauryl sulfate. Where the wetting agent is added by weight, amounts of 0.01 to grams per liter may be used, larger amounts being generally associated with higher content of the primary addition agent.
Further additions may be made of agents that have the function of increasing the bright-plating range. For example, ammonium sulphate in amounts of 1-100 grams per liter has been found effective.
The primary addition agent above referred to as active-sulphuraqmtaining and represented typically by thiourea is not limited to thiourea alone.- The class is characterized generally as containing a bivalent sulphur atom both bonds of which are directly connected to a carbon atom together with one or more nitrogen atoms also directly connected to the carbon atom. It is understood, of course, that in this group of compounds the double bond may in some cases exist or alternate between the sulphur or nitrogen atom and the carbon atom. The thioureas having the nucleus NH s=c and the iso-thiocyanates having the grouping S=C=N are considered representative types. Thiosinamine (allyl thiourea) and thiosemicarbazide may be mentioned as additional examples of the thioureas.
Compounds containing the nucleus characteristic of thioacetamide, and the nucleus 5 s =N-t :-sfor example tetra methyl thiuram monosulphide, are also effective brighteners.
The water soluble mercaptans, for example B-dithioglycoll and thiosalicylic acid have also a brightening eifect.
It will be understood that the compound em ployed should be soluble in the acid bath and should be compatible with the other constituents. Cost and commercial availability will, of course, be factors in determining the product to be used and since thiourea, per CS(NH:) 2, is suitable from all standpoints, it is at present preferred for plant use.
- The constitution of the bath exclusive of the novel addition agents is of standard character.
' For example, aqueous solutions containing 125 to 250 grams per liter of the technical copper sulphate ordinarily supplied for plating and 5 to 100 grams of sulphuric acid are well known and thiourea is effective over the entire range with suitable adjustment as to plating conditions. However, the composition of the bath with reference to the content of copper sulphate and sulphuric acid is not critical within operating limits. It is essential, of course, that materials should not be added to the bath which would precipitate or destroy the brightening effect of the brightening agent. As an illustration of this it is pointed out that the presence of chloride ions to be avoided as much as possible since they tend to precipitate thiourea with consequent loss of brightness.
The temperature of the bath for best results may vary from relatively low limits, for example,
The following may be given, as exampla merely, of baths from which satisfactory results have been obtained:
250 grams technical copper sulphate 35 grams cadmium sulphate 10 grams sulphuric acid 10 grams di-chloro-benzene sulphonic acid 0.1 gram thiourea Water to make'up one liter 250 grams copper sulphate 35 grams nickel phosphate (Nb (P00171120) 10 grams sulphuric acid 10 grams phosphoric acid 10 grams naphthylamine disulphonic acid 0.1 gram thiourea Water to make up one liter (The amounts of the metallic addition agents above are given only by way of examples as the quantities are not at all critical. For best results we recommend, for example, 10-75 grams per liter, which addition may consist of salts of one or more of the metals named.)
250 grams copper sulphate 10 grams sulphuric acid 1 cc. Triton 720" 0.01 gram thiourea Water to make up one liter (This produces a semi-bright deposit which is soft and easily buil'ed.)
250 grams copper sulphate 10 grams sulphuric acid .01 gram thiourea Water to make up one liter 250 grams copper sulphate 10 grams sulphuric acid .03 gram thiosemicarbazide Water to make up one liter 250 grams copper sulphate 10 grams sulphuric acid .02 gram thiosinamine Water to make up one liter The primary addition agent is slowly depleted during the plating operation and is to be replenished as required. The control or range increasing and wetting agents however, other than the metallic type, are apparently not depleted by plating and need replenishing only as the composition of the bath changes due to dragout or addition of fresh bath constituents.
The baths described enable plated deposits of copper, or chiefly of copper, to be obtained which, within a certain medium range of conditions, are truly brilliant. However, even if the conditions are not so accurately maintained as to produce an entirely brilliant deposit or uniform brightness over the entire area, still the deposits are characterized by extreme fineness of crystal structure and remarkable case of buifing to brilliance as compared with copper deposits from the ordinary acid copper baths. The invention is therefore special utility in the plating of objects of irregular contour on which a bright surface is required, as where bright deposits of nickel or chromium are to be later applied. Furthermore, by reason of the reduction in the amount and severity of the bufling operation where such may be necessary, the requirements of labor, equipment, and bufling materials are greatly reduced and the danger of buifing through the coating is substantially eliminated.
We claim:
1. An electrolyte for electrodepositing bright or semi-bright copper consisting essentially of an aqueous acid solution of copper sulphate and free sulphuric acid and having dissolved therein a compound having the nucleus NH- s=c said compound having a concentration in said solution within the range of 0.002- grams per liter.
2. The method of cathodically depositing copper in a form having a substantial degree of brightness comprising passing current through a bath consisting essentially of an aqueous solution of copper sulphate, free sulphuric acid and a thiourea in amount between 0.002 and 5 grams per liter of solution.
3. An electrolyte for the electrodeposition of copper in bright or semi-bright form consisting essentially of an aqueous solution of copper sulphate, sulphuric acid, thiourea and cadmium sluphate in substantially the following proportions, per liter:
Grams Copper sulphate 125-250 Sulphuric acid -50 Thiourea 0.002-5 Cadmium sulphate 10-75 4. An electrolyte for 'electrodepositing copper consisting essentially of an aqueous acid solution of copper sulphate and sulphuric acid and having dissolved therein a thiourea, said thiourea having a concentration in said solution of 0.002-5 grams per liter.-
5. An electrolyte for electrodepositing copper consisting essentially of an aqueous acid solution of copper sulphate and sulphuric acid and having dissolved therein a thiourea and an organic sulphonate wetting agent, said thiourea having a concentration in said solution of 0.002-5 grams per liter, and the wetting agent a concentration of 0.01-5 grams per liter.
6. An electrolyte for electrodeposition of copper in bright or semi-bright form which consists essentially of an aqueous solution of copper sulphate and sulphuric acid to which has been added, per liter of solution, 0.002-5 grams of thiourea.
7. An electrolyte for electrodeposition of cop'- per in bright or semi-bright form which consists essentially of copper sulphate and sulphuric acid to which has been added, per liter of solution, 0.002-5 grams of thiourea and 001-5 grams of a sulphonated ether havin a branch chain and an aromatic nucleus.
8. An electrolyte for electrodeposition of copper in bright or semi-bright form which consists essentially of an aqueous solution of copper sulphate and sulphuric acid to which has been added, per liter of solution, 0.002-5 grams of thiourea and 10-75 grams of a salt of a metal of the class consisting of cadmium, zinc, nickel and cobalt.
9. An electrolyte for electrodeposition of copper in bright or semi-bright form which consists essentially of an aqueous copper sulphate solution containing free sulphuric acid and to which has been added 0.01-0.1 gram of thiourea per liter of solution.
10. An electrolyte for the electrodeposition of copper consisting essentially of an aqueous acid solution of copper sulfate, sulfuric acid, and thiourea, the copper sulfate being present in an amount within the range of to 250 grams per liter, the sulfuric acid within the range of 10 to 50 grams per liter and the thiourea within the range of 0.002 to 5 grams per liter.
11. An electrolyte for the electrodeposition of copper consisting essentially of an aqueous acid solution of copper sulfate, sulfuric acid and thiourea, the copper sulfate being present in an amount within the range of approximately 125 to 250 grams per liter, the sulfuric acid within the range of approximately 10 to 50 grams per liter and thiourea within the range of 0.01 to 0.1 gram per liter.
12. An electrolyte for the electrodeposition of copper consisting essentially of an aqueous acid solution of copper sulphate and free sulphuric acid to which has been added a compound having the nucleus the copper sulphate being present within the range of approximately 125 to 250 grams per liter, the sulphuric acid within the range of approximately 10 to 50 grams per liter and the compound having said nucleus being present within the range of approximately 0.002 to 5 grams per liter.
WILLIAM M. PHILLIPS. FRANK L. CLIFTON.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 103,947 Walenn Dec. 24, 1863 1,328,666 Greenwalt Jan. 26, 1920 1,903,860 Gockel Apr. 18, 1933 2,112,818 Waite Mar. 29, 1938 OTHER REFERENCES Alien Property Custodian Publication 351,241, published May 18, 1943, filed August 3, 1940. Ser. No. 351,241 (A.P.C.), published May 18, 1943.
Certificate of Correction Patent No. 2,563,360 August 7, 1951 WILLIAM M. PHILLIPS ET AL.
It is hereby certified that error appears in the printed specification of the above numbered potent requiring correction as follows:
Column 1, line 14, for effecting and read afiecti ng the; column 2, line 50 for coopper read copper; column 3, line 70, for ions to read ions is to; column 5,1ine 8, for case read ease; and that the said Letters Patent should be read as corrected above, so that the same may conform to the record of the case in the Patent Oflice.
Signed and sealed this 23rd day of October, A. D. 1951.
THOMAS F. MURPHY, v
Auictant Oonwniuiomr of Paton.
Claims (1)
1. AN ELECTROLYTE FOR ELECTRODEPOSITING BRIGHT OR SEMI-BRIGHT COPPER CONSISTING ESSENTIALLY OF AN AQUEOUS ACID SOLUTION OF COPPER SULPHATE AND FREE SULPHURIC ACID AND HAVING DISSOLVED THEREIN A COMPOUND HAVING THE NUCLEUS
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US717333A US2563360A (en) | 1941-05-24 | 1946-12-19 | Electrodeposition of copper |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US39500441A | 1941-05-24 | 1941-05-24 | |
| US717333A US2563360A (en) | 1941-05-24 | 1946-12-19 | Electrodeposition of copper |
| US722756A US2489538A (en) | 1941-05-24 | 1947-01-17 | Electrodeposition of copper |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2563360A true US2563360A (en) | 1951-08-07 |
Family
ID=27410147
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US717333A Expired - Lifetime US2563360A (en) | 1941-05-24 | 1946-12-19 | Electrodeposition of copper |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US2563360A (en) |
Cited By (21)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2677654A (en) * | 1951-05-10 | 1954-05-04 | Poor & Co | Copper electroplating and compositions therefor |
| US2700019A (en) * | 1951-07-05 | 1955-01-18 | Westinghouse Electric Corp | Acid copper plating |
| US2700646A (en) * | 1951-12-07 | 1955-01-25 | Poor & Co | Electroplating zinc copper alloys |
| US2701234A (en) * | 1951-07-11 | 1955-02-01 | Du Pont | Addition agent for copper plating |
| US2730492A (en) * | 1951-12-07 | 1956-01-10 | Poor & Co | Electrodeposition of zinc-copper alloys |
| DE947656C (en) * | 1952-05-26 | 1956-08-23 | Udylite Corp | Bath for the galvanic production of copper coatings |
| US2773022A (en) * | 1953-08-17 | 1956-12-04 | Westinghouse Electric Corp | Electrodeposition from copper electrolytes containing dithiocarbamate addition agents |
| US2799634A (en) * | 1954-02-26 | 1957-07-16 | Westinghouse Electric Corp | Combined addition agents for acid copper plating |
| US3000800A (en) * | 1957-04-16 | 1961-09-19 | Dehydag Gmbh | Copper-electroplating baths |
| US3023152A (en) * | 1961-02-20 | 1962-02-27 | Dehydag Gmbh | Copper electroplating baths |
| DE1218247B (en) * | 1960-06-09 | 1966-06-02 | Riedel & Co | Acid galvanic copper bath |
| US3770599A (en) * | 1971-05-24 | 1973-11-06 | Oxy Metal Finishing Corp | Acid zinc plating baths |
| US4376685A (en) * | 1981-06-24 | 1983-03-15 | M&T Chemicals Inc. | Acid copper electroplating baths containing brightening and leveling additives |
| WO1991004358A1 (en) * | 1989-09-13 | 1991-04-04 | Gould, Inc. | Electrodeposited foil with controlled properties for printed circuit board applications and procedures and electrolyte bath solutions for preparing the same |
| US5171417A (en) * | 1989-09-13 | 1992-12-15 | Gould Inc. | Copper foils for printed circuit board applications and procedures and electrolyte bath solutions for electrodepositing the same |
| US5403465A (en) * | 1990-05-30 | 1995-04-04 | Gould Inc. | Electrodeposited copper foil and process for making same using electrolyte solutions having controlled additions of chloride ions and organic additives |
| US5421985A (en) * | 1990-05-30 | 1995-06-06 | Gould Inc. | Electrodeposited copper foil and process for making same using electrolyte solutions having low chloride ion concentrations |
| US5431803A (en) * | 1990-05-30 | 1995-07-11 | Gould Electronics Inc. | Electrodeposited copper foil and process for making same |
| US5840170A (en) * | 1992-11-30 | 1998-11-24 | Gould Electronics Inc. | Method for inhibiting the electrodeposition of organic particulate matter on copper foil |
| US5958209A (en) * | 1996-05-13 | 1999-09-28 | Mitsui Mining & Smelting Co., Ltd. | High tensile strength electrodeposited copper foil and process of electrodepositing thereof |
| US20040050707A1 (en) * | 2001-01-22 | 2004-03-18 | Hans Warlimont | Continuous electroforming process to form a strip for battery electrodes and a mandrel to be used in said electroforming process |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US103947A (en) * | 1870-06-07 | William henry walenn | ||
| US1328666A (en) * | 1920-01-20 | Metallurgical process | ||
| US1903860A (en) * | 1930-04-25 | 1933-04-18 | Ig Farbenindustrie Ag | Preparation of metallic coatings |
| US2112818A (en) * | 1934-08-15 | 1938-03-29 | Mcgean Chem Co Inc | Electrodeposition of metals |
-
1946
- 1946-12-19 US US717333A patent/US2563360A/en not_active Expired - Lifetime
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US103947A (en) * | 1870-06-07 | William henry walenn | ||
| US1328666A (en) * | 1920-01-20 | Metallurgical process | ||
| US1903860A (en) * | 1930-04-25 | 1933-04-18 | Ig Farbenindustrie Ag | Preparation of metallic coatings |
| US2112818A (en) * | 1934-08-15 | 1938-03-29 | Mcgean Chem Co Inc | Electrodeposition of metals |
Cited By (26)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2677654A (en) * | 1951-05-10 | 1954-05-04 | Poor & Co | Copper electroplating and compositions therefor |
| US2700019A (en) * | 1951-07-05 | 1955-01-18 | Westinghouse Electric Corp | Acid copper plating |
| US2701234A (en) * | 1951-07-11 | 1955-02-01 | Du Pont | Addition agent for copper plating |
| US2700646A (en) * | 1951-12-07 | 1955-01-25 | Poor & Co | Electroplating zinc copper alloys |
| US2730492A (en) * | 1951-12-07 | 1956-01-10 | Poor & Co | Electrodeposition of zinc-copper alloys |
| DE947656C (en) * | 1952-05-26 | 1956-08-23 | Udylite Corp | Bath for the galvanic production of copper coatings |
| US2773022A (en) * | 1953-08-17 | 1956-12-04 | Westinghouse Electric Corp | Electrodeposition from copper electrolytes containing dithiocarbamate addition agents |
| US2799634A (en) * | 1954-02-26 | 1957-07-16 | Westinghouse Electric Corp | Combined addition agents for acid copper plating |
| US3000800A (en) * | 1957-04-16 | 1961-09-19 | Dehydag Gmbh | Copper-electroplating baths |
| DE1218247B (en) * | 1960-06-09 | 1966-06-02 | Riedel & Co | Acid galvanic copper bath |
| US3023152A (en) * | 1961-02-20 | 1962-02-27 | Dehydag Gmbh | Copper electroplating baths |
| US3770599A (en) * | 1971-05-24 | 1973-11-06 | Oxy Metal Finishing Corp | Acid zinc plating baths |
| US4376685A (en) * | 1981-06-24 | 1983-03-15 | M&T Chemicals Inc. | Acid copper electroplating baths containing brightening and leveling additives |
| WO1991004358A1 (en) * | 1989-09-13 | 1991-04-04 | Gould, Inc. | Electrodeposited foil with controlled properties for printed circuit board applications and procedures and electrolyte bath solutions for preparing the same |
| US5171417A (en) * | 1989-09-13 | 1992-12-15 | Gould Inc. | Copper foils for printed circuit board applications and procedures and electrolyte bath solutions for electrodepositing the same |
| US5215645A (en) * | 1989-09-13 | 1993-06-01 | Gould Inc. | Electrodeposited foil with controlled properties for printed circuit board applications and procedures and electrolyte bath solutions for preparing the same |
| AU640169B2 (en) * | 1989-09-13 | 1993-08-19 | Gould Electronics Inc | Electrodeposited foil with controlled properties for printed circuit board applications and procedures and electrolyte bath solutions for preparing the same |
| US5403465A (en) * | 1990-05-30 | 1995-04-04 | Gould Inc. | Electrodeposited copper foil and process for making same using electrolyte solutions having controlled additions of chloride ions and organic additives |
| US5421985A (en) * | 1990-05-30 | 1995-06-06 | Gould Inc. | Electrodeposited copper foil and process for making same using electrolyte solutions having low chloride ion concentrations |
| US5431803A (en) * | 1990-05-30 | 1995-07-11 | Gould Electronics Inc. | Electrodeposited copper foil and process for making same |
| US5454926A (en) * | 1990-05-30 | 1995-10-03 | Gould Electronics Inc. | Electrodeposited copper foil |
| US5840170A (en) * | 1992-11-30 | 1998-11-24 | Gould Electronics Inc. | Method for inhibiting the electrodeposition of organic particulate matter on copper foil |
| US5958209A (en) * | 1996-05-13 | 1999-09-28 | Mitsui Mining & Smelting Co., Ltd. | High tensile strength electrodeposited copper foil and process of electrodepositing thereof |
| US6194056B1 (en) | 1996-05-13 | 2001-02-27 | Mitsui Mining & Smelting Co., Ltd. | High tensile strength electrodeposited copper foil |
| US20040050707A1 (en) * | 2001-01-22 | 2004-03-18 | Hans Warlimont | Continuous electroforming process to form a strip for battery electrodes and a mandrel to be used in said electroforming process |
| US7097754B2 (en) * | 2001-01-22 | 2006-08-29 | Dsl Dresden Material-Innovation Gmbh | Continuous electroforming process to form a strip for battery electrodes and a mandrel to be used in said electroforming process |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US2563360A (en) | Electrodeposition of copper | |
| US2830014A (en) | Electroplating process | |
| US2489538A (en) | Electrodeposition of copper | |
| US2849351A (en) | Electroplating process | |
| US2842488A (en) | Process for the production of metal electrodeposits | |
| US2513280A (en) | Electrodeposition of nickel from an acid bath | |
| US4036709A (en) | Electroplating nickel, cobalt, nickel-cobalt alloys and binary or ternary alloys of nickel, cobalt and iron | |
| US3697391A (en) | Electroplating processes and compositions | |
| US3276979A (en) | Baths and processes for the production of metal electroplates | |
| US3691027A (en) | Method of producing corrosion resistant chromium plated articles | |
| US2840517A (en) | Nickel-iron-zinc alloy electroplating | |
| US2112818A (en) | Electrodeposition of metals | |
| US2550449A (en) | Electrodeposition of nickel from an acid bath | |
| US2469727A (en) | Electrodeposition of nickel | |
| US2700020A (en) | Plating copper | |
| US2849353A (en) | Bright nickel plating | |
| JPS5932554B2 (en) | Acidic plating solution | |
| US2859159A (en) | Bright copper plating bath containing mixtures of metal compounds | |
| US2773022A (en) | Electrodeposition from copper electrolytes containing dithiocarbamate addition agents | |
| US2110792A (en) | Process for electrodeposition of silver and products obtained therefrom | |
| US2539588A (en) | Electrodeposition of nickel | |
| US2648628A (en) | Electroplating of nickel | |
| US2466677A (en) | Electrodeposition of nickel from an acid bath | |
| US2694041A (en) | Electrodeposition of nickel | |
| US2751341A (en) | Electrodeposition of lead and lead alloys |