CN111465719A - Trivalent chromium plating solution and chromium plating method using the same - Google Patents
Trivalent chromium plating solution and chromium plating method using the same Download PDFInfo
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- CN111465719A CN111465719A CN201880080570.2A CN201880080570A CN111465719A CN 111465719 A CN111465719 A CN 111465719A CN 201880080570 A CN201880080570 A CN 201880080570A CN 111465719 A CN111465719 A CN 111465719A
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- Prior art keywords
- trivalent chromium
- chromium plating
- salt
- plating solution
- sulfur
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- 238000007747 plating Methods 0.000 title claims abstract description 128
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 title claims abstract description 72
- 229910052804 chromium Inorganic materials 0.000 title claims abstract description 70
- 239000011651 chromium Substances 0.000 title claims abstract description 70
- 238000000034 method Methods 0.000 title claims description 12
- 150000003839 salts Chemical class 0.000 claims abstract description 43
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 claims abstract description 24
- 150000002894 organic compounds Chemical class 0.000 claims abstract description 24
- 229910052717 sulfur Inorganic materials 0.000 claims abstract description 24
- 239000011593 sulfur Substances 0.000 claims abstract description 24
- 239000008139 complexing agent Substances 0.000 claims abstract description 22
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 claims abstract description 21
- 150000001732 carboxylic acid derivatives Chemical class 0.000 claims abstract description 21
- BFNBIHQBYMNNAN-UHFFFAOYSA-N ammonium sulfate Chemical compound N.N.OS(O)(=O)=O BFNBIHQBYMNNAN-UHFFFAOYSA-N 0.000 claims abstract description 15
- 229910052921 ammonium sulfate Inorganic materials 0.000 claims abstract description 15
- 235000011130 ammonium sulphate Nutrition 0.000 claims abstract description 15
- OTYBMLCTZGSZBG-UHFFFAOYSA-L potassium sulfate Chemical compound [K+].[K+].[O-]S([O-])(=O)=O OTYBMLCTZGSZBG-UHFFFAOYSA-L 0.000 claims abstract description 15
- 229910052939 potassium sulfate Inorganic materials 0.000 claims abstract description 15
- 235000011151 potassium sulphates Nutrition 0.000 claims abstract description 15
- 125000002887 hydroxy group Chemical group [H]O* 0.000 claims abstract description 14
- 125000003903 2-propenyl group Chemical group [H]C([*])([H])C([H])=C([H])[H] 0.000 claims abstract description 12
- 229940081974 saccharin Drugs 0.000 claims abstract description 11
- 235000019204 saccharin Nutrition 0.000 claims abstract description 11
- 239000000901 saccharin and its Na,K and Ca salt Substances 0.000 claims abstract description 11
- CVHZOJJKTDOEJC-UHFFFAOYSA-N saccharin Chemical compound C1=CC=C2C(=O)NS(=O)(=O)C2=C1 CVHZOJJKTDOEJC-UHFFFAOYSA-N 0.000 claims abstract description 10
- 150000001845 chromium compounds Chemical class 0.000 claims abstract description 7
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 44
- 229910052742 iron Inorganic materials 0.000 claims description 22
- 229910017052 cobalt Inorganic materials 0.000 claims description 21
- 239000010941 cobalt Substances 0.000 claims description 21
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims description 21
- 125000004432 carbon atom Chemical group C* 0.000 claims description 8
- LSNNMFCWUKXFEE-UHFFFAOYSA-M Bisulfite Chemical compound OS([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-M 0.000 claims description 6
- JHUFGBSGINLPOW-UHFFFAOYSA-N 3-chloro-4-(trifluoromethoxy)benzoyl cyanide Chemical compound FC(F)(F)OC1=CC=C(C(=O)C#N)C=C1Cl JHUFGBSGINLPOW-UHFFFAOYSA-N 0.000 claims description 5
- WNLRTRBMVRJNCN-UHFFFAOYSA-N adipic acid Chemical compound OC(=O)CCCCC(O)=O WNLRTRBMVRJNCN-UHFFFAOYSA-N 0.000 claims description 4
- HTKFORQRBXIQHD-UHFFFAOYSA-N allylthiourea Chemical compound NC(=S)NCC=C HTKFORQRBXIQHD-UHFFFAOYSA-N 0.000 claims description 4
- 229960001748 allylthiourea Drugs 0.000 claims description 4
- NGPGDYLVALNKEG-OLXYHTOASA-N diammonium L-tartrate Chemical compound [NH4+].[NH4+].[O-]C(=O)[C@H](O)[C@@H](O)C([O-])=O NGPGDYLVALNKEG-OLXYHTOASA-N 0.000 claims description 4
- 238000009713 electroplating Methods 0.000 claims description 4
- XNGIFLGASWRNHJ-UHFFFAOYSA-N phthalic acid Chemical compound OC(=O)C1=CC=CC=C1C(O)=O XNGIFLGASWRNHJ-UHFFFAOYSA-N 0.000 claims description 4
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 claims description 4
- -1 i.e. Chemical compound 0.000 claims description 3
- 239000001361 adipic acid Substances 0.000 claims description 2
- 235000011037 adipic acid Nutrition 0.000 claims description 2
- 239000006179 pH buffering agent Substances 0.000 claims description 2
- BWYYYTVSBPRQCN-UHFFFAOYSA-M sodium;ethenesulfonate Chemical compound [Na+].[O-]S(=O)(=O)C=C BWYYYTVSBPRQCN-UHFFFAOYSA-M 0.000 claims description 2
- 230000008021 deposition Effects 0.000 abstract description 7
- 239000006174 pH buffer Substances 0.000 abstract description 6
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 10
- JOPOVCBBYLSVDA-UHFFFAOYSA-N chromium(6+) Chemical compound [Cr+6] JOPOVCBBYLSVDA-UHFFFAOYSA-N 0.000 description 10
- 239000000203 mixture Substances 0.000 description 10
- 229910001369 Brass Inorganic materials 0.000 description 8
- 239000010951 brass Substances 0.000 description 8
- 150000001875 compounds Chemical class 0.000 description 7
- 238000005260 corrosion Methods 0.000 description 7
- 230000007797 corrosion Effects 0.000 description 7
- 239000011248 coating agent Substances 0.000 description 5
- 238000000576 coating method Methods 0.000 description 5
- 229910052759 nickel Inorganic materials 0.000 description 5
- 208000014451 palmoplantar keratoderma and congenital alopecia 2 Diseases 0.000 description 5
- 238000001095 inductively coupled plasma mass spectrometry Methods 0.000 description 4
- 125000001741 organic sulfur group Chemical group 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- KGBXLFKZBHKPEV-UHFFFAOYSA-N boric acid Chemical compound OB(O)O KGBXLFKZBHKPEV-UHFFFAOYSA-N 0.000 description 3
- 239000004327 boric acid Substances 0.000 description 3
- DSHWASKZZBZKOE-UHFFFAOYSA-K chromium(3+);hydroxide;sulfate Chemical compound [OH-].[Cr+3].[O-]S([O-])(=O)=O DSHWASKZZBZKOE-UHFFFAOYSA-K 0.000 description 3
- 229910000356 chromium(III) sulfate Inorganic materials 0.000 description 3
- 235000015217 chromium(III) sulphate Nutrition 0.000 description 3
- 239000011696 chromium(III) sulphate Substances 0.000 description 3
- 238000000921 elemental analysis Methods 0.000 description 3
- CIWBSHSKHKDKBQ-JLAZNSOCSA-N Ascorbic acid Chemical compound OC[C@H](O)[C@H]1OC(=O)C(O)=C1O CIWBSHSKHKDKBQ-JLAZNSOCSA-N 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- WINXNKPZLFISPD-UHFFFAOYSA-M Saccharin sodium Chemical compound [Na+].C1=CC=C2C(=O)[N-]S(=O)(=O)C2=C1 WINXNKPZLFISPD-UHFFFAOYSA-M 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- ZOJBYZNEUISWFT-UHFFFAOYSA-N allyl isothiocyanate Chemical compound C=CCN=C=S ZOJBYZNEUISWFT-UHFFFAOYSA-N 0.000 description 2
- 229910021538 borax Inorganic materials 0.000 description 2
- 229910001430 chromium ion Inorganic materials 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- WLJVNTCWHIRURA-UHFFFAOYSA-N pimelic acid Chemical compound OC(=O)CCCCCC(O)=O WLJVNTCWHIRURA-UHFFFAOYSA-N 0.000 description 2
- 238000001556 precipitation Methods 0.000 description 2
- CXMXRPHRNRROMY-UHFFFAOYSA-N sebacic acid Chemical compound OC(=O)CCCCCCCCC(O)=O CXMXRPHRNRROMY-UHFFFAOYSA-N 0.000 description 2
- 235000010339 sodium tetraborate Nutrition 0.000 description 2
- UMGDCJDMYOKAJW-UHFFFAOYSA-N thiourea Chemical compound NC(N)=S UMGDCJDMYOKAJW-UHFFFAOYSA-N 0.000 description 2
- BSVBQGMMJUBVOD-UHFFFAOYSA-N trisodium borate Chemical compound [Na+].[Na+].[Na+].[O-]B([O-])[O-] BSVBQGMMJUBVOD-UHFFFAOYSA-N 0.000 description 2
- FTLYMKDSHNWQKD-UHFFFAOYSA-N (2,4,5-trichlorophenyl)boronic acid Chemical class OB(O)C1=CC(Cl)=C(Cl)C=C1Cl FTLYMKDSHNWQKD-UHFFFAOYSA-N 0.000 description 1
- BJEPYKJPYRNKOW-REOHCLBHSA-N (S)-malic acid Chemical compound OC(=O)[C@@H](O)CC(O)=O BJEPYKJPYRNKOW-REOHCLBHSA-N 0.000 description 1
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 1
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 1
- 239000004251 Ammonium lactate Substances 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical group [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910021555 Chromium Chloride Inorganic materials 0.000 description 1
- FEWJPZIEWOKRBE-JCYAYHJZSA-N Dextrotartaric acid Chemical compound OC(=O)[C@H](O)[C@@H](O)C(O)=O FEWJPZIEWOKRBE-JCYAYHJZSA-N 0.000 description 1
- 229920007019 PC/ABS Polymers 0.000 description 1
- 239000002202 Polyethylene glycol Substances 0.000 description 1
- FEWJPZIEWOKRBE-UHFFFAOYSA-N Tartaric acid Natural products [H+].[H+].[O-]C(=O)C(O)C(O)C([O-])=O FEWJPZIEWOKRBE-UHFFFAOYSA-N 0.000 description 1
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Natural products NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 1
- NOGBENJVEVQHKG-UHFFFAOYSA-K [Cr+3].NS([O-])(=O)=O.NS([O-])(=O)=O.NS([O-])(=O)=O Chemical compound [Cr+3].NS([O-])(=O)=O.NS([O-])(=O)=O.NS([O-])(=O)=O NOGBENJVEVQHKG-UHFFFAOYSA-K 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 235000016720 allyl isothiocyanate Nutrition 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
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- 235000011114 ammonium hydroxide Nutrition 0.000 description 1
- 229940059265 ammonium lactate Drugs 0.000 description 1
- 235000019286 ammonium lactate Nutrition 0.000 description 1
- 235000010323 ascorbic acid Nutrition 0.000 description 1
- 239000011668 ascorbic acid Substances 0.000 description 1
- 229960005070 ascorbic acid Drugs 0.000 description 1
- 238000003321 atomic absorption spectrophotometry Methods 0.000 description 1
- 229910002090 carbon oxide Inorganic materials 0.000 description 1
- 150000001735 carboxylic acids Chemical class 0.000 description 1
- 150000001844 chromium Chemical class 0.000 description 1
- QSWDMMVNRMROPK-UHFFFAOYSA-K chromium(3+) trichloride Chemical compound [Cl-].[Cl-].[Cl-].[Cr+3] QSWDMMVNRMROPK-UHFFFAOYSA-K 0.000 description 1
- WYYQVWLEPYFFLP-UHFFFAOYSA-K chromium(3+);triacetate Chemical compound [Cr+3].CC([O-])=O.CC([O-])=O.CC([O-])=O WYYQVWLEPYFFLP-UHFFFAOYSA-K 0.000 description 1
- 238000000975 co-precipitation Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- HTXDPTMKBJXEOW-UHFFFAOYSA-N dioxoiridium Chemical compound O=[Ir]=O HTXDPTMKBJXEOW-UHFFFAOYSA-N 0.000 description 1
- ZPWVASYFFYYZEW-UHFFFAOYSA-L dipotassium hydrogen phosphate Chemical compound [K+].[K+].OP([O-])([O-])=O ZPWVASYFFYYZEW-UHFFFAOYSA-L 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229960002163 hydrogen peroxide Drugs 0.000 description 1
- 229910000457 iridium oxide Inorganic materials 0.000 description 1
- 239000001630 malic acid Substances 0.000 description 1
- 235000011090 malic acid Nutrition 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000001000 micrograph Methods 0.000 description 1
- 229920001223 polyethylene glycol Polymers 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- LJCNRYVRMXRIQR-OLXYHTOASA-L potassium sodium L-tartrate Chemical compound [Na+].[K+].[O-]C(=O)[C@H](O)[C@@H](O)C([O-])=O LJCNRYVRMXRIQR-OLXYHTOASA-L 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- HELHAJAZNSDZJO-OLXYHTOASA-L sodium L-tartrate Chemical compound [Na+].[Na+].[O-]C(=O)[C@H](O)[C@@H](O)C([O-])=O HELHAJAZNSDZJO-OLXYHTOASA-L 0.000 description 1
- PPASLZSBLFJQEF-RKJRWTFHSA-M sodium ascorbate Substances [Na+].OC[C@@H](O)[C@H]1OC(=O)C(O)=C1[O-] PPASLZSBLFJQEF-RKJRWTFHSA-M 0.000 description 1
- 235000010378 sodium ascorbate Nutrition 0.000 description 1
- 229960005055 sodium ascorbate Drugs 0.000 description 1
- 235000011006 sodium potassium tartrate Nutrition 0.000 description 1
- 239000001433 sodium tartrate Substances 0.000 description 1
- 229960002167 sodium tartrate Drugs 0.000 description 1
- 235000011004 sodium tartrates Nutrition 0.000 description 1
- PPASLZSBLFJQEF-RXSVEWSESA-M sodium-L-ascorbate Chemical compound [Na+].OC[C@H](O)[C@H]1OC(=O)C(O)=C1[O-] PPASLZSBLFJQEF-RXSVEWSESA-M 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 235000002906 tartaric acid Nutrition 0.000 description 1
- 239000011975 tartaric acid Substances 0.000 description 1
- WUUHFRRPHJEEKV-UHFFFAOYSA-N tripotassium borate Chemical compound [K+].[K+].[K+].[O-]B([O-])[O-] WUUHFRRPHJEEKV-UHFFFAOYSA-N 0.000 description 1
Images
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
- C25D3/04—Electroplating: Baths therefor from solutions of chromium
- C25D3/10—Electroplating: Baths therefor from solutions of chromium characterised by the organic bath constituents used
-
- 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
- C25D3/04—Electroplating: Baths therefor from solutions of chromium
- C25D3/06—Electroplating: Baths therefor from solutions of chromium from solutions of trivalent chromium
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/10—Electroplating with more than one layer of the same or of different metals
- C25D5/12—Electroplating with more than one layer of the same or of different metals at least one layer being of nickel or chromium
- C25D5/14—Electroplating with more than one layer of the same or of different metals at least one layer being of nickel or chromium two or more layers being of nickel or chromium, e.g. duplex or triplex layers
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
The present invention provides a trivalent chromium plating solution containing a trivalent chromium compound, a complexing agent, potassium sulfate and ammonium sulfate as conductive salts, a pH buffer, and a sulfur-containing organic compound, characterized in that a carboxylic acid having 2 or more hydroxyl groups and 2 or more carboxyl groups or a salt thereof is used as the complexing agent, and saccharin or a salt thereof and a sulfur-containing organic compound having an allyl group are used in combination as the sulfur-containing organic compound, whereby the plating layer is deposited at a high deposition rate and is practically used.
Description
Technical Field
The present invention relates to a trivalent chromium plating bath and a chromium plating method using the same.
Background
The chromium plating layer has a silvery white appearance and is used as a decorative coating film. Hexavalent chromium has been used for the chromium plating, but in recent years, the use of hexavalent chromium has been limited because it affects the environment, and the technique has been shifted to trivalent chromium.
As a technique using trivalent chromium, there have been many reports, and for example, a chromium electrolytic plating solution containing a water-soluble trivalent chromium salt, a complexing agent for trivalent chromium ions such as malic acid, a pH buffer compound, a sulfur-containing organic compound such as thiourea, and a water-soluble compound such as saccharin, and having a pH of 2.8 to 4.2 is known (patent document 1).
However, the plating layer of the trivalent chromium plating bath has a slow deposition rate and is not a practical product.
Documents of the prior art
Patent document
Patent document 1: japanese patent No. 5696134
Disclosure of Invention
Problems to be solved by the invention
The present invention addresses the problem of providing a trivalent chromium plating solution that has a high plating layer deposition rate and is practical.
Means for solving the problems
As a result of intensive studies to solve the above problems, the present inventors have found that a trivalent chromium plating solution is a practical chromium plating solution having a high plating deposition rate by using a carboxylic acid having 2 or more hydroxyl groups and 2 or more carboxyl groups or a salt thereof as a complexing agent for trivalent chromium ions and using saccharin or a salt thereof in combination with a compound having an allyl group as a sulfur-containing organic compound, and have completed the present invention.
That is, the present invention relates to a trivalent chromium plating bath comprising a trivalent chromium compound, a complexing agent, potassium sulfate and ammonium sulfate as conductive salts, a pH buffer, and a sulfur-containing organic compound,
as the complexing agent, a carboxylic acid having 2 or more hydroxyl groups and 2 or more carboxyl groups or a salt thereof is used,
as the sulfur-containing organic compound, saccharin or a salt thereof and a sulfur-containing organic compound having an allyl group are used in combination.
The present invention also relates to a method for plating chromium on an object to be plated, wherein the object to be plated is plated with the trivalent chromium plating solution.
The present invention also relates to a chromium-plated product obtained by plating an object to be plated with the trivalent chromium plating solution.
Effects of the invention
The trivalent chromium plating solution of the present invention is a plating solution using trivalent chromium, but can provide an appearance comparable to that of a plating solution using hexavalent chromium, and has a high deposition rate of a plating layer, and is practical.
Drawings
FIG. 1 is a diagram showing the positions of distances for measuring the spreading ability in the Hull cell test of example 1.
FIG. 2 is a graph showing the relationship between the ratio of potassium sulfate to ammonium sulfate contained in a trivalent chromium plating bath and the throwing power in the Hull cell test of example 1.
Fig. 3 is a graph showing the results of a corrosion resistance test (CASS test).
Detailed Description
The trivalent chromium plating solution of the present invention (hereinafter referred to as "plating solution of the present invention") is a trivalent chromium plating solution containing a trivalent chromium compound, a complexing agent, potassium sulfate and ammonium sulfate as conductive salts, a pH buffer, and a sulfur-containing organic compound,
as the complexing agent, a carboxylic acid having 2 or more hydroxyl groups and 2 or more carboxyl groups or a salt thereof is used,
as the sulfur-containing organic compound, saccharin or a salt thereof and a sulfur-containing organic compound having an allyl group are used in combination.
The trivalent chromium compound used in the plating solution of the invention is not particularly limited, and is, for example, basic chromium sulfate, chromium chloride, chromium sulfamate, chromium acetate, preferably basic chromium sulfate, and the content of the trivalent chromium compound in the plating solution of the invention is not particularly limited, and is, for example, 1 to 25 g/L, preferably 5 to 15 g/L, in terms of metallic chromium.
The complexing agent used in the plating solution of the present invention is a carboxylic acid having 2 or more hydroxyl groups and 2 or more carboxyl groups or a salt thereof, and examples of the complexing agent include salts of the above carboxylic acids such as tartaric acid, diammonium tartrate, rochelle salt, sodium tartrate, and the like, and the content of the carboxylic acid or a salt thereof in the plating solution of the present invention is not particularly limited, and is, for example, 5 to 90 g/L, preferably 10 to 60 g/L.
The conductive salt used in the plating solution of the present invention is potassium sulfate and ammonium sulfate, the content of potassium sulfate and ammonium sulfate in the plating solution of the present invention is not particularly limited, and is, for example, 100 to 300 g/L, preferably 120 to 240 g/L, in total, the mass ratio of potassium sulfate to ammonium sulfate (potassium sulfate/ammonium sulfate) is 0.5 to 60, preferably 1.0 to 30, and when the mass ratio of potassium sulfate/ammonium sulfate is within the above range, a good coating force is exhibited, and a chromium plating film can be formed even on a plated object having a complicated shape even in a low current density portion.
The pH buffer used in the plating solution of the present invention is not particularly limited, and is boric acid, sodium borate, potassium borate, phosphoric acid, dipotassium hydrogen phosphate, etc., preferably boric acid and sodium borate, and the pH buffer may be 1 or 2 or more in combination.
The organic sulfur-containing compound used in the plating solution of the present invention is, in combination with saccharin or a salt thereof, used as an organic sulfur-containing compound having an allyl group, and examples of saccharin or a salt thereof include saccharin, sodium saccharin, and the like, and examples of the organic sulfur-containing compound having an allyl group include sodium allylsulfonate, allylthiourea, ammonium 2-methallylsulfonate, and allyl isothiocyanate, and 1 or a combination of 2 or more of these organic sulfur-containing compounds having an allyl group, and sodium allylsulfonate and/or allylthiourea are preferable.
The plating solution of the present invention may further contain ascorbic acid, sodium ascorbate, hydrogen peroxide, polyethylene glycol, and the like.
The pH of the plating solution of the present invention is not particularly limited if it is acidic, and is, for example, preferably 2 to 4.5, more preferably 2.5 to 4.0.
The method for preparing the plating solution of the present invention is not particularly limited, and for example, the plating solution can be prepared by adding and mixing a trivalent chromium compound, a complexing agent, a conductive salt, and a pH buffering agent in water at 40 to 50 ℃, adding and mixing a sulfur-containing organic compound after dissolution, and finally adjusting the pH with sulfuric acid, ammonia water, or the like.
The plating solution of the present invention can be used for plating a chromium-containing plating solution to a plating object by electroplating the plating object with the plating solution of the present invention.
The conditions of the plating are not particularly limited, and for example, the bath temperature is 30 to 60 ℃, the anode is carbon or iridium oxide, and the cathode current density is 2 to 20A/dm2Electroplating for 1-15 min.
Examples of the plating object that can be plated include metals such as iron, stainless steel, and brass, and resins such as ABS and PC/ABS. The member to be plated may be subjected to a treatment such as copper plating or nickel plating in advance before the treatment with the plating solution of the present invention.
The chromium plating product thus obtained has an appearance, dispersibility, and precipitation rate comparable to those of hexavalent chromium.
Next, as another embodiment of the plating bath of the present invention, a practical trivalent chromium plating bath having a high plating layer deposition rate and excellent color tone and corrosion resistance will be described.
In addition to the above-mentioned substances, the complexing agents of the plating solution of the present invention may be a carboxylic acid having 2 or more carboxyl groups and 4 or more carbon atoms or a salt thereof, examples of the carboxylic acid having 2 or more carboxyl groups and 4 or more carbon atoms or a salt thereof include a carboxylic acid such as adipic acid, phthalic acid, pimelic acid, sebacic acid, and a salt thereof, and when a carboxylic acid having 2 or more hydroxyl groups and 2 or more carboxyl groups or a salt thereof and a carboxylic acid having 2 or more carboxyl groups and 4 or more carbon atoms or a salt thereof are used in combination, the two complexing agents may be 1 or 2 or more of each of them, and when a carboxylic acid having 2 or more hydroxyl groups and 2 or more carboxyl groups or a salt thereof and a carboxylic acid having 2 or more carboxyl groups and 4 or more carbon atoms or a salt thereof are used in combination, the total content of the complexing agents in the plating solution of the present invention is not particularly limited, and is, for example, 5 to 90 g/L, preferably 10 to 60 g/L in total of the complexing agents.
The sulfur-containing organic compound in the plating solution of the present invention is not particularly limited, and for example, the total amount of all the sulfur-containing organic compounds is 0.5 to 10 g/L, preferably 2 to 8 g/L.
The plating solution of the present invention using the complexing agent and the sulfur-containing organic compound as described above can be prepared by the above-described preparation method. In addition, the plating object can be plated with chrome by the above method.
The chromium-plated product thus obtained has a color tone equivalent to that of hexavalent chromium, and has high corrosion resistance, and is a chromium plating layer having high practicability. Therefore, the chromium-plated product is suitable for parts such as automobiles, motorcycles, faucet metal parts, and the like, which require corrosion resistance.
In addition, although a general trivalent chromium plating solution contains iron and cobalt in order to improve the throwing power to a low current density, the plating solution of the present invention described above has an improved throwing power even if it does not contain iron and/or cobalt. In addition, in the case of a plating solution containing iron and cobalt, the corrosion resistance tends to decrease in the plating film due to the co-precipitation of iron and cobalt. Therefore, the plating solution of the present invention preferably contains substantially no iron and/or cobalt. The plating solution of the present invention contains substantially no iron and/or cobalt means that iron and/or cobalt is 2ppm or less, preferably 1ppm or less, and more preferably 0.5ppm or less. The amount of iron and/or cobalt can be analyzed by an ICP-MS method, atomic absorption spectrophotometry, or the like.
In addition, in the case where the plating solution of the present invention does not substantially contain iron and/or cobalt, the resulting chromium plated product also does not substantially contain iron and/or cobalt. The chromium plating product of the present invention is substantially free of iron and/or cobalt means that the amount of iron and/or cobalt in the chromium plating layer is less than 0.5 at%, preferably 0.4 at% or less. The amount of iron and/or cobalt can be analyzed using EDS, XPS, or the like.
Examples
The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples.
Example 1
And (3) chromium plating:
the trivalent chromium plating solution was prepared by dissolving the components described in table 1 in water, and a hell bath test was performed using a brass plate on which nickel plating was performed under the conditions of current 4A and plating time of 3 minutes, and after plating, the distance from the left end of the brass plate where the plating film was deposited was measured as shown in fig. 1, and the measured distance was taken as the spreading ability.
[ TABLE 1 ]
| Plating solution composition | Composition 1 | Composition 2 | Composition 3 | Composition 4 | Composition 5 | Composition 6 |
| Basic chromium sulfate (g/L) | 64 | 64 | 64 | 64 | 64 | 64 |
| Diammonium tartrate (g/L)*1 | 30 | 30 | 30 | 30 | 30 | - |
| Ammonium lactate (g/L)*2 | - | - | - | - | - | 30 |
| Potassium sulfate (g/L) | 150 | 150 | 150 | 150 | 150 | 150 |
| Ammonium sulfate (g/L) | 20 | 20 | 20 | 20 | 20 | 20 |
| Boric acid (g/L) | 80 | 80 | 80 | 80 | 80 | 80 |
| Saccharin sodium salt (g/L) | 4 | 4 | 4 | 4 | 4 | 4 |
| Sodium allylsulfonate (36%) (ml/L) | 1.58 | - | - | - | - | 1.58 |
| Sodium vinylsulfonate (27.5%) (ml/L) | - | 1 | - | - | - | - |
| Sodium propiolate (20%) (ml/L) | - | - | 1 | - | - | - |
| Allylthiourea (ppm) | - | - | - | 10 | 20 | - |
| pH of the plating solution | 3.4 | 3.4 | 3.4 | 3.4 | 3.4 | 3.4 |
| Bath temperature (. degree. C.) | 45 | 45 | 45 | 45 | 45 | 45 |
| Capacity of dispersing (mm) | 75 | 75 | -※ | 75 | 74 | 74 |
| Film thickness (mum) | 0.15 | 0.07 | -※ | 0.13 | 0.15 | 0.08 |
| Appearance L value | 82.38 | 75.47 | -※ | 82.60 | 82.40 | 80.01 |
| Appearance a value | -0.76 | -0.29 | -※ | -0.76 | -0.72 | -0.75 |
| B value of appearance | -0.42 | 1.94 | -※ | -0.22 | -0.33 | 0.23 |
The color is as follows: no precipitation of coating
1: 2 hydroxyl groups, 2 carboxyl groups
2: 1 hydroxyl, 1 carboxyl
The corresponding hexavalent chromium coating has a L value of 84, an a value of-1.0 and a b value of-1.0
From these results, it was found that by using diammonium tartrate (2 hydroxyl groups and 2 carboxyl groups) as a complexing agent and sodium saccharin in combination with sodium allylsulfonate or allylthiourea (a sulfur-containing organic compound having an allyl group) (compositions 1, 4 and 5) as the sulfur-containing organic compound in the trivalent chromium plating solution, the appearance was about the same as that of the hexavalent chromium plating layer, and the film thickness (deposition rate) was about 2 times as large as that in the case where the trivalent chromium plating solution was not used.
The contents of iron and cobalt in the trivalent chromium plating bath were measured by ICP-MS and were less than 0.5ppm, respectively. Further, as a result of measuring iron and cobalt in the obtained chromium plating layer by elemental analysis by EDS, they were respectively less than 0.4 at%.
Example 2
And (3) chromium plating:
the components described in table 2 were dissolved in water to prepare a trivalent chromium plating solution. For the trivalent chromium plating solution, a hell cell test was performed using a brass plate plated with nickel. The conditions for the Hull cell test were current 4A, plating time 3 minutes. After plating, the distance from the left end of the brass plate at which the plating film was deposited was measured. The results are also shown in Table 2. Further, the relationship between the spreadability and potassium sulfate/ammonium sulfate is shown in FIG. 2.
[ TABLE 2 ]
When plating is performed using the trivalent chromium plating solution, it is found that the appearance and the film thickness are substantially the same in all compositions, but the spreading ability is better as potassium sulfate/ammonium sulfate is larger, and particularly good in the spreading ability at 1.0 to 30.
The contents of iron and cobalt in the trivalent chromium plating bath measured by the ICP-MS method were less than 0.5ppm, respectively. Further, as a result of measuring iron and cobalt in the obtained chromium plating layer by elemental analysis by EDS, they were less than 0.4 at%, respectively.
Example 3
And (3) chromium plating:
the trivalent chromium plating solution was prepared by dissolving the components described in table 3 in water, and a hell bath test was performed using a brass plate on which nickel plating was performed under the conditions of current 4A and plating time of 3 minutes, and after plating, the distance from the left end of the brass plate at which a plating film was deposited was measured as shown in fig. 1, and the measured distance was used as a spreading ability, and the thickness of the portion of the brass plate corresponding to a current density of 8ASD was measured by a fluorescent X-ray, and the appearance after plating was evaluated by a colorimeter (manufactured by konica minolta) according to L values, a values, and b values, and the results are also shown in table 3.
[ TABLE 3 ]
The corresponding hexavalent chromium coating has a L value of 84, an a value of-1.0 and a b value of-1.0
From the results, it is understood that the appearance of the trivalent chromium plating bath is similar to that of the hexavalent chromium plating bath by using a combination of a carboxylic acid having 2 or more hydroxyl groups and 2 or more carboxyl groups or a salt thereof and a carboxylic acid having 2 or more carboxyl groups and 4 or more carbon atoms or a salt thereof as a complexing agent, and a combination of saccharin or a salt thereof, a sulfonic acid having an allyl group or a salt thereof, and a sulfonic acid having a vinyl group or a salt thereof as a sulfur-containing organic compound.
The contents of iron and cobalt in the trivalent chromium plating bath measured by the ICP-MS method were less than 0.5ppm, respectively. Further, as a result of measuring iron and cobalt in the obtained chromium plating layer by elemental analysis by EDS, they were less than 0.4 at%, respectively.
Example 4
CASS test:
trivalent chromium plating baths having compositions 16, 18, 20 and 21 shown in table 3 were prepared. The trivalent chromium plating bath was applied to a nickel (2 μm) plated copper plate at a bath temperature of 45 ℃ and a current density of 8A/dm2And carrying out chromium plating for 3 minutes to obtain a test piece. The test piece was subjected to CASS test (JIS H8502). Fig. 3 shows a micrograph of a test piece 24 hours after the CASS test.
As a result of the CASS test, it was found that corrosion pores are less dispersed and corrosion resistance is improved by using a carboxylic acid having 2 or more hydroxyl groups and 2 or more carboxyl groups or a salt thereof in combination with a carboxylic acid having 2 or more carboxyl groups and having 4 or more carbon atoms or a salt thereof as a complexing agent, and saccharin or a salt thereof, a sulfonic acid having an allyl group or a salt thereof, and a sulfonic acid having a vinyl group or a salt thereof as a sulfur-containing organic compound in combination in a trivalent chromium plating solution.
Industrial applicability
The trivalent chromium plating solution of the present invention can be used for various uses as in the plating using hexavalent chromium.
Claims (11)
1. A trivalent chromium plating solution is characterized in that the trivalent chromium plating solution contains a trivalent chromium compound, a complexing agent, potassium sulfate and ammonium sulfate as conductive salts, a pH buffering agent and a sulfur-containing organic compound,
as the complexing agent, a carboxylic acid having 2 or more hydroxyl groups and 2 or more carboxyl groups or a salt thereof is used,
as the sulfur-containing organic compound, saccharin or a salt thereof and a sulfur-containing organic compound having an allyl group are used in combination.
2. The trivalent chromium plating bath according to claim 1,
the carboxylic acid or salt thereof having more than 2 hydroxyl groups is diammonium tartrate.
3. The trivalent chromium plating solution according to claim 1 or 2, wherein,
the mass ratio of potassium sulfate to ammonium sulfate, i.e., potassium sulfate/ammonium sulfate, is 1.0-30.
4. The trivalent chromium plating solution according to any one of claims 1 to 3, wherein,
the sulfur-containing organic compound having an allyl group is sodium allylsulfonate and/or allylthiourea.
5. The trivalent chromium plating solution according to any one of claims 1 to 4, wherein,
as the complexing agent, a carboxylic acid having 2 or more carboxyl groups and 4 or more carbon atoms or a salt thereof is further used, and as the sulfur-containing organic compound, a sulfonic acid having a vinyl group or a salt thereof is further used.
6. The trivalent chromium plating bath according to claim 5, wherein,
the carboxylic acid or its salt having 2 or more carboxyl groups and 4 or more carbon atoms is phthalic acid or adipic acid.
7. The trivalent chromium plating bath according to claim 5, wherein,
the sulfonic acid having a vinyl group or a salt thereof is sodium vinylsulfonate.
8. The trivalent chromium plating solution according to claim 1 to 7, wherein,
which is substantially free of iron and/or cobalt.
9. A method for plating chromium on an object to be plated,
electroplating the object to be plated with the trivalent chromium plating solution according to any one of claims 1 to 8.
10. A chromium-plated product is prepared from chromium-plated product,
the plating bath is obtained by plating a plating object with the trivalent chromium plating bath according to any one of claims 1 to 8.
11. The chrome plated product according to claim 10,
the chromium deposit is substantially free of iron and/or cobalt.
Applications Claiming Priority (5)
| Application Number | Priority Date | Filing Date | Title |
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| JP2017-238232 | 2017-12-13 | ||
| JP2017238232 | 2017-12-13 | ||
| JP2018-083550 | 2018-04-25 | ||
| JP2018083550 | 2018-04-25 | ||
| PCT/JP2018/045593 WO2019117178A1 (en) | 2017-12-13 | 2018-12-12 | Trivalent chromium plating solution and method for chromium-plating using same |
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| CN111465719A true CN111465719A (en) | 2020-07-28 |
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| Country | Link |
|---|---|
| US (1) | US20210172081A1 (en) |
| EP (1) | EP3725920A4 (en) |
| JP (1) | JP6951465B2 (en) |
| KR (1) | KR20200096239A (en) |
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| WO (1) | WO2019117178A1 (en) |
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| EP3859053A1 (en) | 2020-01-31 | 2021-08-04 | COVENTYA S.p.A. | Sulfate based, ammonium free trivalent chromium decorative plating process |
| MX2022004290A (en) * | 2019-10-31 | 2022-05-10 | Coventya S P A | Sulfate based, ammonium free trivalent chromium decorative plating process. |
| JP2023018744A (en) * | 2021-07-28 | 2023-02-09 | 株式会社Jcu | White trivalent chromium plating bath and white trivalent chromium plating method for object to be plated using the same |
| CN114875459A (en) * | 2022-05-10 | 2022-08-09 | 成立航空股份有限公司 | Trivalent chromium plating solution and black chromium plating layer |
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| US4450052A (en) * | 1982-07-28 | 1984-05-22 | M&T Chemicals Inc. | Zinc and nickel tolerant trivalent chromium plating baths |
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| EP2705176B1 (en) * | 2011-05-03 | 2016-04-13 | ATOTECH Deutschland GmbH | Electroplating bath and method for producing dark chromium layers |
| CN103668348A (en) * | 2012-09-04 | 2014-03-26 | 无锡福镁轻合金科技有限公司 | Plating method of total-sulfate trivalent chromium plating solution |
| CN108866586B (en) * | 2018-07-05 | 2020-01-07 | 厦门大学 | Electroplating solution for electrodepositing ferrochromium alloy in trivalent chromium system and preparation method thereof |
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2018
- 2018-12-12 US US16/770,357 patent/US20210172081A1/en not_active Abandoned
- 2018-12-12 EP EP18889584.1A patent/EP3725920A4/en not_active Withdrawn
- 2018-12-12 WO PCT/JP2018/045593 patent/WO2019117178A1/en unknown
- 2018-12-12 CN CN201880080570.2A patent/CN111465719A/en active Pending
- 2018-12-12 KR KR1020207017354A patent/KR20200096239A/en unknown
- 2018-12-12 JP JP2019559679A patent/JP6951465B2/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4473448A (en) * | 1981-02-09 | 1984-09-25 | W. Canning Materials Limited | Electrodeposition of chromium |
| US20100243463A1 (en) * | 2009-03-24 | 2010-09-30 | Herdman Roderick D | Chromium Alloy Coating with Enhanced Resistance to Corrosion in Calcium Chloride Environments |
| CN101967662A (en) * | 2010-10-26 | 2011-02-09 | 广东多正化工科技有限公司 | Trivalent chromium electroplate liquid capable of forming black clad layer |
| CN103668345A (en) * | 2012-09-04 | 2014-03-26 | 无锡福镁轻合金科技有限公司 | Total-sulfate trivalent chromium plating solution |
| US20150354085A1 (en) * | 2013-01-10 | 2015-12-10 | Coventya Inc. | Apparatus and methods of maintaining trivalent chromium bath plating efficiency |
| CN105671599A (en) * | 2016-04-11 | 2016-06-15 | 济南德锡科技有限公司 | Sulfate trivalent chromium electroplating solution and preparation method thereof |
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| JPWO2019117178A1 (en) | 2020-12-17 |
| EP3725920A1 (en) | 2020-10-21 |
| WO2019117178A1 (en) | 2019-06-20 |
| US20210172081A1 (en) | 2021-06-10 |
| EP3725920A4 (en) | 2021-04-21 |
| JP6951465B2 (en) | 2021-10-20 |
| KR20200096239A (en) | 2020-08-11 |
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