US3577328A - Method and bath for electroplating tin - Google Patents
Method and bath for electroplating tin Download PDFInfo
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- US3577328A US3577328A US774177A US3577328DA US3577328A US 3577328 A US3577328 A US 3577328A US 774177 A US774177 A US 774177A US 3577328D A US3577328D A US 3577328DA US 3577328 A US3577328 A US 3577328A
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- per liter
- bath
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- tin
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- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 title abstract description 38
- 238000009713 electroplating Methods 0.000 title abstract description 9
- 238000000034 method Methods 0.000 title description 26
- 239000000203 mixture Substances 0.000 abstract description 25
- 230000003595 spectral effect Effects 0.000 abstract description 18
- 239000002253 acid Substances 0.000 abstract description 15
- 230000001464 adherent effect Effects 0.000 abstract description 15
- 239000000758 substrate Substances 0.000 abstract description 6
- 150000001299 aldehydes Chemical class 0.000 abstract description 4
- MTNDZQHUAFNZQY-UHFFFAOYSA-N imidazoline Chemical compound C1CN=CN1 MTNDZQHUAFNZQY-UHFFFAOYSA-N 0.000 abstract description 4
- 150000002500 ions Chemical class 0.000 abstract description 4
- 150000002462 imidazolines Chemical class 0.000 description 48
- -1 heterocyclic aldehyde Chemical class 0.000 description 38
- 229940083254 peripheral vasodilators imidazoline derivative Drugs 0.000 description 23
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Natural products OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 21
- 239000004094 surface-active agent Substances 0.000 description 21
- IUTCEZPPWBHGIX-UHFFFAOYSA-N tin(2+) Chemical compound [Sn+2] IUTCEZPPWBHGIX-UHFFFAOYSA-N 0.000 description 20
- 125000000623 heterocyclic group Chemical group 0.000 description 19
- MBVFRSJFKMJRHA-UHFFFAOYSA-N 4-fluoro-1-benzofuran-7-carbaldehyde Chemical group FC1=CC=C(C=O)C2=C1C=CO2 MBVFRSJFKMJRHA-UHFFFAOYSA-N 0.000 description 18
- 125000004432 carbon atom Chemical group C* 0.000 description 17
- 238000007747 plating Methods 0.000 description 16
- 229910052783 alkali metal Inorganic materials 0.000 description 14
- 125000000217 alkyl group Chemical group 0.000 description 12
- 150000001340 alkali metals Chemical class 0.000 description 11
- 125000000129 anionic group Chemical group 0.000 description 11
- IAYPIBMASNFSPL-UHFFFAOYSA-N Ethylene oxide Chemical compound C1CO1 IAYPIBMASNFSPL-UHFFFAOYSA-N 0.000 description 10
- 125000002947 alkylene group Chemical group 0.000 description 10
- GPRLSGONYQIRFK-UHFFFAOYSA-N hydron Chemical compound [H+] GPRLSGONYQIRFK-UHFFFAOYSA-N 0.000 description 10
- 125000001424 substituent group Chemical group 0.000 description 10
- GOOHAUXETOMSMM-UHFFFAOYSA-N Propylene oxide Chemical compound CC1CO1 GOOHAUXETOMSMM-UHFFFAOYSA-N 0.000 description 8
- 150000002431 hydrogen Chemical class 0.000 description 7
- 229910052739 hydrogen Inorganic materials 0.000 description 7
- 239000001257 hydrogen Substances 0.000 description 7
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical class CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 6
- 239000011260 aqueous acid Substances 0.000 description 6
- 150000001721 carbon Chemical group 0.000 description 6
- 229910052799 carbon Inorganic materials 0.000 description 6
- 150000001875 compounds Chemical class 0.000 description 6
- HYBBIBNJHNGZAN-UHFFFAOYSA-N furfural Chemical compound O=CC1=CC=CO1 HYBBIBNJHNGZAN-UHFFFAOYSA-N 0.000 description 6
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 5
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 5
- RCIVOBGSMSSVTR-UHFFFAOYSA-L stannous sulfate Chemical compound [SnH2+2].[O-]S([O-])(=O)=O RCIVOBGSMSSVTR-UHFFFAOYSA-L 0.000 description 5
- 239000001117 sulphuric acid Substances 0.000 description 5
- 235000011149 sulphuric acid Nutrition 0.000 description 5
- 229910000375 tin(II) sulfate Inorganic materials 0.000 description 5
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 4
- 230000009286 beneficial effect Effects 0.000 description 4
- 230000008901 benefit Effects 0.000 description 4
- 230000015572 biosynthetic process Effects 0.000 description 4
- 235000019441 ethanol Nutrition 0.000 description 4
- CNUDBTRUORMMPA-UHFFFAOYSA-N formylthiophene Chemical compound O=CC1=CC=CS1 CNUDBTRUORMMPA-UHFFFAOYSA-N 0.000 description 4
- 125000000896 monocarboxylic acid group Chemical group 0.000 description 4
- 239000002904 solvent Substances 0.000 description 4
- 239000010959 steel Substances 0.000 description 4
- QXNVGIXVLWOKEQ-UHFFFAOYSA-N Disodium Chemical class [Na][Na] QXNVGIXVLWOKEQ-UHFFFAOYSA-N 0.000 description 3
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- 238000013019 agitation Methods 0.000 description 3
- 229910052782 aluminium Inorganic materials 0.000 description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 3
- 239000002738 chelating agent Substances 0.000 description 3
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 3
- 238000001914 filtration Methods 0.000 description 3
- 238000009472 formulation Methods 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 150000007530 organic bases Chemical class 0.000 description 3
- ZSKGQVFRTSEPJT-UHFFFAOYSA-N pyrrole-2-carboxaldehyde Chemical compound O=CC1=CC=CN1 ZSKGQVFRTSEPJT-UHFFFAOYSA-N 0.000 description 3
- 125000002948 undecyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 3
- LCALOJSQZMSPHJ-QMMMGPOBSA-N (2s)-2-amino-3-cyclohexa-1,5-dien-1-ylpropanoic acid Chemical compound OC(=O)[C@@H](N)CC1=CCCC=C1 LCALOJSQZMSPHJ-QMMMGPOBSA-N 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- YLQBMQCUIZJEEH-UHFFFAOYSA-N Furan Chemical compound C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- KAESVJOAVNADME-UHFFFAOYSA-N Pyrrole Chemical compound C=1C=CNC=1 KAESVJOAVNADME-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 2
- YTPLMLYBLZKORZ-UHFFFAOYSA-N Thiophene Chemical compound C=1C=CSC=1 YTPLMLYBLZKORZ-UHFFFAOYSA-N 0.000 description 2
- 229960000583 acetic acid Drugs 0.000 description 2
- 150000007513 acids Chemical class 0.000 description 2
- HUMNYLRZRPPJDN-UHFFFAOYSA-N benzaldehyde Chemical compound O=CC1=CC=CC=C1 HUMNYLRZRPPJDN-UHFFFAOYSA-N 0.000 description 2
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 230000002452 interceptive effect Effects 0.000 description 2
- 239000002932 luster Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 229910052759 nickel Inorganic materials 0.000 description 2
- 239000010802 sludge Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 239000001211 (E)-4-phenylbut-3-en-2-one Substances 0.000 description 1
- KJPRLNWUNMBNBZ-QPJJXVBHSA-N (E)-cinnamaldehyde Chemical compound O=C\C=C\C1=CC=CC=C1 KJPRLNWUNMBNBZ-QPJJXVBHSA-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
- ZNQVEEAIQZEUHB-UHFFFAOYSA-N 2-ethoxyethanol Chemical compound CCOCCO ZNQVEEAIQZEUHB-UHFFFAOYSA-N 0.000 description 1
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical group [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- KCXVZYZYPLLWCC-UHFFFAOYSA-N EDTA Chemical compound OC(=O)CN(CC(O)=O)CCN(CC(O)=O)CC(O)=O KCXVZYZYPLLWCC-UHFFFAOYSA-N 0.000 description 1
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 1
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 1
- QPCDCPDFJACHGM-UHFFFAOYSA-N N,N-bis{2-[bis(carboxymethyl)amino]ethyl}glycine Chemical compound OC(=O)CN(CC(O)=O)CCN(CC(=O)O)CCN(CC(O)=O)CC(O)=O QPCDCPDFJACHGM-UHFFFAOYSA-N 0.000 description 1
- 239000004372 Polyvinyl alcohol Substances 0.000 description 1
- 235000011054 acetic acid Nutrition 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000032683 aging Effects 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- BJEPYKJPYRNKOW-UHFFFAOYSA-N alpha-hydroxysuccinic acid Natural products OC(=O)C(O)CC(O)=O BJEPYKJPYRNKOW-UHFFFAOYSA-N 0.000 description 1
- 230000003466 anti-cipated effect Effects 0.000 description 1
- 125000004429 atom Chemical group 0.000 description 1
- 229930008407 benzylideneacetone Natural products 0.000 description 1
- 238000005282 brightening Methods 0.000 description 1
- 125000002837 carbocyclic group Chemical group 0.000 description 1
- 239000003518 caustics Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 229940117916 cinnamic aldehyde Drugs 0.000 description 1
- KJPRLNWUNMBNBZ-UHFFFAOYSA-N cinnamic aldehyde Natural products O=CC=CC1=CC=CC=C1 KJPRLNWUNMBNBZ-UHFFFAOYSA-N 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 239000002659 electrodeposit Substances 0.000 description 1
- LYCAIKOWRPUZTN-UHFFFAOYSA-N ethylene glycol Natural products OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 125000004435 hydrogen atom Chemical group [H]* 0.000 description 1
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000010348 incorporation Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000001630 malic acid Substances 0.000 description 1
- 235000011090 malic acid Nutrition 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 239000011572 manganese Substances 0.000 description 1
- MGFYIUFZLHCRTH-UHFFFAOYSA-N nitrilotriacetic acid Chemical compound OC(=O)CN(CC(O)=O)CC(O)=O MGFYIUFZLHCRTH-UHFFFAOYSA-N 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 125000004433 nitrogen atom Chemical group N* 0.000 description 1
- QNGNSVIICDLXHT-UHFFFAOYSA-N para-ethylbenzaldehyde Natural products CCC1=CC=C(C=O)C=C1 QNGNSVIICDLXHT-UHFFFAOYSA-N 0.000 description 1
- 229960003330 pentetic acid Drugs 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 229920002451 polyvinyl alcohol Polymers 0.000 description 1
- JLKDVMWYMMLWTI-UHFFFAOYSA-M potassium iodate Chemical compound [K+].[O-]I(=O)=O JLKDVMWYMMLWTI-UHFFFAOYSA-M 0.000 description 1
- 239000001230 potassium iodate Substances 0.000 description 1
- 229940093930 potassium iodate Drugs 0.000 description 1
- 235000006666 potassium iodate Nutrition 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- BDERNNFJNOPAEC-UHFFFAOYSA-N propan-1-ol Chemical compound CCCO BDERNNFJNOPAEC-UHFFFAOYSA-N 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 229940071182 stannate Drugs 0.000 description 1
- 125000005402 stannate group Chemical group 0.000 description 1
- 229910052572 stoneware Inorganic materials 0.000 description 1
- 229930192474 thiophene Natural products 0.000 description 1
- 150000003606 tin compounds Chemical class 0.000 description 1
- BWHOZHOGCMHOBV-BQYQJAHWSA-N trans-benzylideneacetone Chemical compound CC(=O)\C=C\C1=CC=CC=C1 BWHOZHOGCMHOBV-BQYQJAHWSA-N 0.000 description 1
- 239000002023 wood Substances 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
- C25D3/30—Electroplating: Baths therefor from solutions of tin
- C25D3/32—Electroplating: Baths therefor from solutions of tin characterised by the organic bath constituents used
Definitions
- An aqueous bath for electroplating tin upon various conductive substrates contains stannous ion, sulfate radical, an irnidazoline derivative and a heterocyclic aldehyde.
- the bath is highly acid and is operable to produce smooth adherent deposits over a wide range of current densities and deposits of spectral brightness with the optimum formulations.
- Another object is to provide such a bath for electrodepositing tin at suitable operating rates which is operable over a broad range of current densities to provide deposits of spectral brightness.
- a specific object is to provide a convenient and relatively rapid method for electroplating tin upon metallic workpieces utilizing an improved sulfate plating bath to obtain highly desirable tin deposits at relatively low cost.
- a surface active agent selected from the group consisting of irnidazoline derivatives and mixtures of irnidazoline derivatives with condensates of an alkyl phenol having an alkyl chain of 6.to 12 carbon atoms with an alkylene oxide selected from the class consisting of ethylene oxide, propylene oxide and mixtures thereof, and 0.005 to 1.0 gram per liter of a heterocyclic aldehyde wherein the heterocyclic ring has five members and the carboxaldehyde group is attached to a carbon atom in the ring.
- the bath is highly acid and contains about 1.5 to 4.5 grams per liter of hydrogen ion.
- the preferred baths utilize an irnidazoline derivative in combination with an alkyl phenol-alkylene oxide condensate since such a combination makes possible electrodeposits exhibiting spectral brightness over a wide range of current density.
- the baths are useful for still and barrel plating and are operable over a fairly wide range of current density.
- the aqueous bath is prepared and maintained at a tem perture of about 45 to Fahrenheit.
- the workpiece which has a conductive surface and a suitable high-purity tin anode are immersed in the bath and a voltage is applied to provide a current density of about 0.5 to 150.0 amperes per square foot at the surface of the workpiece.
- a smooth, adherent, ductile deposit of tin is produced which may vary from bright to spectral bright depending upon the current density and whether the optimum formulation is employed for a given set of conditions, as will be pointed out more fully hereinafter;
- the acid baths of the present invention require the stannous ion, the sulfate radical, an irnidazoline derivative and the heterocyclic aldehyde for proper operation.
- the stannous ion and the sulfate radical may be furnished to the bath by any combination of compounds suitable for use in tin plating solutions, but to avoid the presence of unnecessary and possibly interfering ions, these components are desirably introduced in the form of stannous sulfate and sulphuric acid.
- the former compound vw'll provide both the stannous ion and the sulfate radical, whereas the latter compound provide additional sulfate radical which is present in the bath.
- the use of sulphuric acid is also desirable from the standpoint of control of the hydrogen ion concentration, although other acids providing non-interfering radicals may also be used for that purpose.
- Tin compounds other than stannous sulfate, e.g., stannous fluoborate may be employed, but preferably they are used in amounts of not more than about 50 percent by weight of the sulfate compound, and preferably less than 20 percent by weight thereof.
- the amount of stannous ion present in the baths may vary between about 10.0 and 50.0 grams per liter, it is preferably about 12.0 to 20.0 grams per liter.
- the concentration of sulfate ion may normally be between about 100.0 and 250.0, it is preferably about 175.0 to 225.0 grams per liter.
- a broad range of about 1.5 to 4.5 grams per liter is suitable for the hydrogen ion concentration, it is most desirably maintained at about 2.5 to 3.5 grams per liter. If the concentration of stannous ion in the bath is too low, the efiiciency of plating and the quality of the deposit produced will be unsatisfactory at the low current density area; burning will be apparent at the high density area.
- R represents an alkyl radical having to 24 carbon atoms
- G is OH ion, an acid salt radical, an anionic surface-active sulfate salt radical such as preferably OSO -OR, or an anionic surface-active sulfonate salt radical
- Z is CCOM, CH COOM, or HO-CHCH SO M radical.
- the substituent designated M in the foregoing formula is a hydrogen atom, an alkali metal or an organic base, and that designated Y is either an OR' or N (:R') A group.
- Each R substituent is independently selected from the group consisting of hydrogen, alkali metals, and -(CH COOM;
- A represents an anionic monovalent radical and n represents an integer from 1 to 4.
- Use of the dotted line representation for the bonds connecting the substituents G and CH Z to the nitrogen atom indicates that these substituents are optionally present or absent, but it should be understood that they are either both present or both absent.
- Desirable compounds are provided when, in accordance with the foregoing formula, G represents the radical par ucularly in which R is a C to C alkyl group, and Z is a COOM radical in which M is preferably an alkali metal cation.
- Exemplary of the compounds corresponding to the foregoing formula which are satisfactory for use in the baths described herein are 2-alkyl-l-(ethyl-beta-oxypropanoic acid) imidazolines wherein the alkyl group is capryl, undecyl or a mixture of C C chains, and the disodium salt of lauroyl-cycloimidinium-l-ethoxyethanoic acid 2- ethanoic acid.
- the imidazoline derivatives provide a desirable degree of brightening when used alone, generally the full advantages of the present invention can be attained only by use of imidazoline derivatives in combination with the condensate of an alkyl phenol and alkylene oxides.
- the alkylene oxide willbe present in a molar ratio relative to the alkyl phenol of about 8 to 25:1 and is selected from the class consisting of ethylene oxide, propylene oxide and mixtures thereof.
- the alkyl substituent on the phenol has a carbonchain of 6 to 12 carbon atoms and preferably '8 to 10.
- alkyl phenol condensates are octyl phenoxy polyethoxy ethanols and nonyl phenoxy polyethoxy ethanols with the preferred agents being nonyl phenoxy polyethoxy ethanols having a molar ratio of about 9 to,20:1.
- the total concentration of the surface-active agent may vary from about 0.2 to 20.0 grams per liter and is preferably in the range of about 1.0- to 4.0 grams per liter.
- the preferred surface-active agents are, in fact, a combination of the imidazoline derivative and the alkyl phenol condensate. Particularly beneficial results have been obtained by the use of the imidazoline in an amount of about 1.0 to 2.5 grams per liter and the alkyl phenol condensate in the amount of about 1.0 to 1.0 gram per liter.
- a highly beneficial system is that obtained by a mixture of an imidazoline corresponding to the aforementioned general formula wherein Z is COONa, G is OH, and Y is OCH COONa', and a second imidazoline wherein the groups G and CH Z are omitted and Y is N CH CH COOH) 2 (CH COOH) Cl
- the first-mentioned imidazoline derivative is provided in a weight ratio of about 1 to 8:1 relative to the secondmentioned imidazoline derivative and preferably in a ratio of about 4.5 to 6.5.
- the heterocyclic carboxaldehydes The other essential component in the system is the heterocyclic carboxaldehyde which acts as a primary brightener.
- the heterocyclic ring is five membered and may be based upon thiophene, furan and pyrrole.
- the carboxaldehyde group is attached to one of the carbons in the ring which generally will be in the 2-position, and the preferred compounds are those in which a simple carboxaldehyde group (CHO) is employed although longer carbon chain carboxaldehydes may also be employed; in addition, the carboxaldehydes may be ringor chain-substituted materials.
- Specific heterocyclic carboxaldehydes which have proved highly effective are furfural (2-furaldehyde), 2-thiophene carboxaldehyde and 2-pyrrole carboxaldehyde.
- the brightener is preferably included in amounts of at least 0.01 and desirably at least 0.05 gram per liter.
- the amount of aldehyde is increased above about 0.5 gram per liter, there is a greater difficulty in controlling the operation of the bath. Above 1.0 gram per liter, pitting and burning become quite evident and the low current density area on a test panel no longer is bright. Accordingly, the baths preferably employ the aldehyde compounds in amounts of about 0.05 to 0.5 gram per liter.
- the heterocyclic carboxaldehydes demonstrate relatively low solubility in the acid bath, it may be necessary to employ a solvent solution thereof to facilitate formation of the bath composition.
- various solvents which may be employed, depending upon the particular aldehyde selected, are the low molecular weight alkanols (methanol, ethanol and propanol) and the low molecular weight glycol ethers (ethylene glycol monoethyl ether, etc.).
- the aldehyde is added to the solvent in amounts of about 1.0 to 50.0 grams per liter thereof and preferably in about 5.0 to 25.0 grams per liter, so as to obtain a stable solvent solution which may be readily dispersed in the acid bath.
- auxiliary brighteners which may be added are the aryl aldehydes (benzaldehyde, cinnamaldehyde), polyvinyl alcohol and carbocyclic and heterocyclic ketones (benzylideneacetone, furylideneacetone and pyridylideneacetone).
- aryl aldehydes benzaldehyde, cinnamaldehyde
- polyvinyl alcohol polyvinyl alcohol
- carbocyclic and heterocyclic ketones benzylideneacetone, furylideneacetone and pyridylideneacetone.
- auxiliary brighteners should be added in amounts of less than 1.0 gram per liter and preferably less than 0.2 gram per liter.
- a chelating agent such as citric acid, malic acid and the aminopolyacetic acids (ethylenediamine tetraacetic acid, diethylenetriamine pentaacetic acid, and nitrilotriacetic acid.
- chelating agents when employed, are generally included in an amount of 5.0 to 20.0 grams per liter.
- the baths of the present invention are operable over a relatively wide range of cathode current density. More specifically, the operable range is about 0.5 to 150 amperes per square foot (a.s.f.) and preferably about 1 to 45 a.s.f., with a narrower range of to 30 a.s.f. being most desirable for barrel plating operations.
- the plating efliciency is generally quite high and will range up to about 98 percent, based upon the theoretical rate of deposition, at current densities below about amperes per square foot.
- the anodezcathode area ratio should be about 1.0 to 3.0:1.0, and preferably about 2..0:1.0.
- the anode current density should not exceed about 15 a.s.f. since there is an apparent tendency for polarization of the anode, for the brightener to become unstable and for formation of tetravalent tin.
- the applied voltage should be about 0.2 to 5.0 volts and preferably 0.5 to 4.0 volts.
- the baths should be operated at temperatures between about 45 and 135 Fahrenheit, and preferably about 55 to 85 Fahrenheit. Operation below about 45 Fahrenheit tends to be inefiiicent and to produce undesirable deposits, whereas temperatures higher than about 135 Fahrenheit tend to produce dull, rough and generally unacceptable deposits.
- Any metallic substrate or metal-surfaced article which can be plated with tin using prior art baths may be coated in accordance with the present invention.
- good deposits of tin may be produced upon articles of copper, nickel, iron and steel. The best results are obtainable with these baths if relatively pure tin anodes are employed.
- Agitation is desirable to obtain deposits which are uniform and of high quality and to avoid development of sludge or film. Not only is agitation of the bath itself desirable but agitation of the cathode may be desirable to obtain a uniform plate and to enable extension of the range of satisfactory current density to higher levels.
- the process is adapted to both still plating and barrel plating apparatus with equal eflicacy.
- Filtration of the bath is not essential but will normally be beneficial when contamination of the bath is encountered due to airborne impurities and carryover from other finishing operations.
- Various filtering media may be utilized including fabric, porous stoneware and other conventional filtering materials.
- the depletion of the various components of the bath is best corrected by analysis for the several components on a periodic basis which can be established for a given facility.
- the best procedure is to evaluate a sample of the bath in a suitable test cell, and a suitable schedule may be established for a given facility and workpiece.
- a suitable schedule may be established for a given facility and workpiece.
- Example One An aqueous bath is prepared containing 30.0 grams per liter of stannous sulfate, 108.0 milliliters per liter of sulphuric acid (specific gravity 1.84), 0.6 gram per liter of an imidazoline derivative wherein groups G and CH Z are omitted and Y is N(CH CH COOH) 2 (CH COOH) Cl 0.1 gram per liter of an imidazoline derivative wherein Z is COONa, G is OH, and Y is OCH COONa, and 0.25 gram per liter of an ethylene oxide/octyl phenol condensate having a molar ratio of about 10.0:1.0, and 0.08 gram per liter of thiophene aldehyde.
- the bath was introduced into a barrel plating apparatus and maintained at a temperature of about 68 Fahrenheit.
- the printed circuit packages were removed from the bath and were found to have an electroplated tin deposit of about 0.3 mil.
- the deposit was spectral bright in all current density areas of the parts and was free from burning. The deposit was also found to be highly adherent.
- Example Two The procedure of Example One was substantially repeated utilizing transistors with wire leads. The cathode current density was calculated to average about 15 a.s.f. Upon removal from the bath, the transistors and the wire leads were found to be plated with a spectral bright tin deposit of about 0.3 mil thickness. Flexing of the leads did not produce any evidence of cracking of the plated deposit or of lack of adherence of the deposit to the substrate.
- Example Three The procedure of Example One was again repeated utilizing as the parts being treated sheet metal and wood screw fasteners fabricated from a steel alloy. The average cathode current density was calculated at about 15 a.s.f. and the parts were found to have a spectral bright, adherent tin deposit of about 0.3 mil. thickness over their entire surface area.
- Example Four In a rack plating tank were placed bearings fabricated of steel with a bonded aluminum backing. The bath in this instance was maintained at a temperature of about 60 Fahrenheit and the current applied across the tank was calculated to produce an average cathode current density of about 25 a.s.f. After 12 minutes, the parts were removed and were found to have a spectral bright tin deposit of about 0.5 mil thickness. The deposit was ductile and highly adherent to the steel portion of the bearings although adherence to the aluminum backing was typically poor as can be anticipated for an electroplated tin deposit on aluminum.
- Example Five The procedure of Example Four was repeated utilizing printed circuit boards fabricated of copper with a screened resist pattern. The temperature of the bath was maintained at about 68 Fahrenheit and the cathode current density was calculated to average 15 a.s.f. After 11.5 minutes, the parts were removed from the bath and found to have a spectral bright, highly adherent tin deposit of about 0.3 mil thickness over the resist-free areas.
- Example Six Part A The bath of Example One was tested in a rotary test cell manufactured by Conversion Chemical Corporation of Rockville, Conn. in accordance with US. Letters Pat. No. 3,215,609. The test panels were cleaned steel and the potential applied across the cell was 1.0 volt developing an amperage of about 1.5. The temperature was maintained at about 68 Fahrenheit and after plating for 6 minutes, the test panels were removed and found to be bright over the entire range of about 0.5 to 100.0 amperes per square foot.
- Part B. The procedure was repeated substituting for the thiophene aldehyde an equal amount of pyrrole aldehyde. Again, the test panels were found to be spectral bright throughout the current density range of about 5.0 to 100.0 a.s.f., but a slight fogginess tending to reduce the otherwise brilliant luster was apparent in the area below about 5.0 a.s.f.
- Example Seven The procedure of Example Six, Part A, was repeated omitting the ethylene oxide/octyl phenol condensate.
- the test panels were found to have a spectral bright tin deposit in the range of about 25.0 to 100.0 a.s.f. Below about 25.0 a.s.f., there were portions of the test panels which were unplated indicating a tendency toward skip plating in the lower current density areas.
- the plated deposits were spectral bright. This and related tests indicate the very significant benefits to be obtained by combining the imidazoline derivatives with the alkyl phenol/alkylene oxide condensates.
- Example Eight The procedure of Example Six, Part A, was repeated omitting from the bath the second-mentioned imidazoline derivative.
- the plated deposit was uniform and adherent throughout the current density range of about 1.0 to 100.0 a.s.f. Although the deposit was bright or non-matte in character, it was not so spectral bright as that obtained by the combination of the imidazoline derivatives in the preferred bath of Example One.
- Example Nine The procedure of Example Six, Part A, was repeated utilizing a standard Hull cell. The temperature of the bath was maintained at about 90 Fahrenheit and a voltage of about 3.0 was applied across the cell. After plating for about 3.0 minutes, the test panels were found to have a spectral bright, adherent tin deposit over a range of about 25.0 to 135.0 a.s.f.
- the present invention provides a novel and highly efiective bath for electroplating tin on various metallic substrates.
- the deposits are adherent and ductile and may vary from bright to spectral bright depending upon whether the optimum formulations are employed.
- Various types of parts may be readily plated over a relatively wide range of current density.
- An aqueous acid bath for producing an adherent electroplated tin deposit comprising about 10.0 to 50.0 grams per liter of stannous ion; about 100.0 to 250.0 grams per liter of sulfate radical; about 0.2 to 20.0 grams per liter of a surface active agent selected from the group consisting of imidazoline derivatives and mixtures of imidazoline derivatives with condensates of an alkyl phenol having an alkyl chain of 6 to 12 carbon atoms with an alkylene oxide selected from the class consisting of ethylene oxide, propylene oxide, and mixtures thereof; 0.005 to 1.0 gram per liter of a heterocyclic carboxaldehyde wherein the heterocyclic ring has five members and the carboxaldehyde group is attached to a carbon atom on said ring; and about 1.5 to 4.5 grams per liter of hydrogen ion.
- R" is an alkyl radical having 5 to 24 carbon atoms
- G is a radical selected from the group consisting of OH, acid salt radicals, anionic surface active sulfate salt radicals, and anionic surface active sulfonate salt radicals;
- Z is a radical selected from the group consisting of -COOM, CH COOM, and
- M is a substituent selected from the group consisting of hydrogen, alkali metals and organic bases;
- Y is selected from the group consisting of OR and --N(R') A;
- each R substituent is independently selected from the group consisting of hydrogen, alkali metals, and --(CH COOM;
- A is an anionic monovalent radical
- n is an integer from 1 to 4.
- said imidazoline derivative is selected from the group consisting of 2-alkyl-l- (ethyl-beta-oxypropanoic acid)-imidazolines wherein the alkyl group is selected from the class consisting of capryl, undecyl and mixtures of C7-C17 chains, and the disodium salt of lauroyl-cyclo-imidinium-l-ethoxy-ethanoic acid-2- ethanoic acid.
- said surface active agent comprises 1.0 to 2.5 grams per liter of an imidazoline derivative and 0.1 to 1.0 gram per liter of an alkyl phenol condensate.
- the bath of claim 1 wherein the stannous ion concentration is about 12.0 to 20.0 grams per liter, the sulfate radical concentration is about 175.0 to 225.0 grams per liter, the surface active agent concentration is about 1.0 to 4.0 grams per liter and the heterocyclic aldehyde concentration is about 0.0 5 to 0.5 gram per liter.
- An aqueous acid bath for producing an adherent electroplated tin deposit comprising about 10.0 to 50.0 grams per liter of stannous ion; about 100.0 to 250.0 grams per liter of sulfate radical; about 0.2 to 20.0 grams per liter of a surface active agent selected from the group consisting of imidazoline derivatives and mixtures of imidazoline derivatives with condensates of an alkyl phenol having an alkyl chain of 6 to 12 carbon atoms with an alkylene oxide selected from the class consisting of ethylene oxide, propylene oxide, and mixtures thereof; 0.005 to 1.0 gram per liter of an heterocyclic carboxaldehyde wherein the heterocyclic ring has five members and the carboxaldehyde group is attached to a carbon atom on said ring; and about 1.5 to 4.5 grams per liter of hydrogen ion, said imidazoline derivative corresponding to the formula:
- R is an alkyl radical having 10 to 18 carbon atoms
- M is an alkali metal cation
- Y is selected from the group consisting of OR' and N(R') A
- each R substituent is independently selected from the group consisting of hydrogen, alkali metals, and
- R" is an alkyl radical having 5 to 24 carbon atoms
- A is an anionic monovalent radical
- n is an integer from 1 to 4.
- An aqueous acid bath for producing an adherent electroplated tin deposit comprising about 10.0 to 50.0 grams per liter of stannous ion; about 100.0 to 250.0 grams per liter of sulfate radical; about 0.2 to 20.0 grams per liter of a surface active agent selected from the group consisting of both imidazoline derivatives (A) and (B) and mixtures of both imidazoline derivatives (A) and (B) with condensates of an alkyl phenol having an alkyl chain of 6 to 12 carbon atoms with an alkylene oxide selected from the class consisting of ethylene oxide, propylene oxide, and mixtures thereof; 0.005 to l/O gram per liter of a heterocyclic carboxaldehyde wherein the heterocyclic ring has five members and the carboxaldehyde group is attached to a carbon atom on said ring; and about 1.5 to 4.5 grams per liter of hydrogen ion, each of said imidazoline derivatives (A) and
- imidazoline derivative (A) is present in a weight ratio relative to imidazoline derivative (B) of about 1.0 to 8.0: 1.0.
- said surface-active agent contains both the imidazoline derivatives and the alkyl phenol condensate, the imidazoline derivatives being present in an amount of about 1.0 to 2.5 grams per liter and the condensate being present in an amount of about 0.1 to 1.0 gram per liter.
- the bath of claim 11 wherein the stannous ion concentration is about 12.0 to 20.0 grams per liter, the sulfate radical concentration is about 175.0 to 225.0 grams per liter, the surface active agent concentration is about 1.0 to 4.0 grams per liter and the heterocyclic aldehyde concentration is about 0.05 to 0.5 gram per liter.
- an aqueous acid bath comprising about 10.0 to 50.0 grams per liter of stannous ion; about 100.0 to 250.0 grams per liter of sulfate radical; about 0.2 to 20.0 grams per liter of a surface-active agent selected from the group consisting of imidazoline derivatives and mixtures of imidazoline derivatives with condensates of an alkyl phenol having an 10 alkyl chain of 6 to 12 carbon atoms with an alkylene oxide selected from the class consisting of ethylene oxide, propylene oxide, and mixtures thereof; about 1.5 to 4.5 grams per liter of hydrogen ion; and about 0.005 to 1.0 gram per liter of a heterocyclic carboxaldehyde wherein the heterocyclic ring has five members and the carboxaldehyde group is attached to a carbon atom in said ring;
- R" is an alkyl radical having 5 to 24 carbon atoms
- G is a radical selected from the group consisting of -OH, acid salt radicals, anionic surface-active sulfate salt radicals, and anionic surface-active sulfonate salt radicals;
- Z is a radical selected from the group consisting of COOM, CH COOM, and HO-CH--CH SO M;
- M is a substituent selected from the group consisting of hydrogen, alkali metals and organic bases;
- Y is selected from the group consisting of OR' and N(R') A;
- each R substituent is independently selected from the group consisting of hydrogen, alkali metals, and --(CH COOM;
- A is an anionic monovalent radical
- n is an integer from 1 to 4.
- said surface-active agent comprises 1.0 to 2.5 grams per liter of an imidazoline derivative and 0.1 to 1.0 gram per liter of an alkyl phenol condensate.
- the stannous ion concentration is about 12.0 to 20.0 grams per liter
- the sulfate radical concentration is about 175.0 to 225.0 grams per liter
- the surface-active agent concentration is about 1.0 to 4.0 grams per liter
- the heterocyclic aldehyde concentration is about 0.05 to 0.5 gram per liter.
- said imidazoline derivative is selected from the group consisting of 2-alkyl- 1-(ethyl-beta-oxypropanoic acid)-imidazolines wherein the alkyl group is selected from the class consisting of capryl, undecyl and mixtures of C -C chains, and the disodium salt of lauroyl-cyclo-imidinium-l-ethoxy-ethanoic acid 2-ethanoic acid.
- a surface-active agent selected from the group consisting of imidazoline derivatives and mixtures of imidazoline derivatives with condensates of an alkyl phenol having an alkyl chain of 6 to 12 carbon atoms with an alkylene oxide selected from the class consisting of ethylene oxide, propylene oxide, and mixtures thereof; about 1.5 to 4.5 grams per liter of hydrogen ion; and about 0.005 to 1.0 gram per liter of a heterocyclic carboxaldehyde wherein the heterocyclic ring has five members and the carboxaldehyde group is attached to a carbon atom in said ring; said imidazoline derivative corresponding to the formula:
- R is an alkyl radical having to 18 carbon atoms
- M is an alkali metal cation
- Y is selected from the group consisting of OR' and N(R) A
- each R substituent is independently selected from the group consisting of hydrogen, alkali metals, and -(CH COOM
- R" is an alkyl radical having 5 to 24 carbon atoms
- A is an anionic monovalent radical and n is an integer from 1 to 4;
- aqueous acid bath comprising about 10.0 to 50.0 grams per liter of stannous ion; about 100.0 to 250.0 grams per liter of sulfate radical; about 0.2 to 20.0 grams per liter of a surface-active agent selected from the group consisting of both imidazoline derivatives (A) and (B) and mixtures of both imidazoline derivatives (A) and (B) with condensates of an alkyl phenol having an alkyl chain of 6 to 12 carbon atoms with an alkylene oxide selected from the class consisting of ethylene oxide, propylene oxide, and mixtures thereof; about 1.5 to 4.5 grams per liter of hydrogen ion; and about 0.005 to 1.0 gram per liter of heterocyclic carboxaldehyde wherein the heterocyclic ring has five members and the carboxaldehyde group is attached to acarbon 12 atom in said ring, each of said imidazoline derivatives (A) and (B) corresponding to the formula wherein R
- stannous ion concentration is about 12.0 to 20.0 grams per liter
- sulfate radical concentration is about 175.0 to 225.0 grams per liter
- surface-active agent concentration is about 1.0 to 4.0 grams per liter
- heterocyclic aldehyde concentration is about 0.05 to 0.5 grams per liter.
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- 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)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US77417768A | 1968-11-07 | 1968-11-07 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3577328A true US3577328A (en) | 1971-05-04 |
Family
ID=25100474
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US774177A Expired - Lifetime US3577328A (en) | 1968-11-07 | 1968-11-07 | Method and bath for electroplating tin |
Country Status (7)
| Country | Link |
|---|---|
| US (1) | US3577328A (enExample) |
| JP (1) | JPS4920703B1 (enExample) |
| DE (1) | DE1956144C2 (enExample) |
| FR (1) | FR2022820A1 (enExample) |
| GB (1) | GB1263591A (enExample) |
| MY (1) | MY7500119A (enExample) |
| SE (1) | SE362097B (enExample) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4880507A (en) * | 1987-12-10 | 1989-11-14 | Learonal, Inc. | Tin, lead or tin/lead alloy electrolytes for high speed electroplating |
| US5174887A (en) * | 1987-12-10 | 1992-12-29 | Learonal, Inc. | High speed electroplating of tinplate |
| WO2018219848A1 (en) | 2017-06-01 | 2018-12-06 | Basf Se | Composition for tin alloy electroplating comprising leveling agent |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3755096A (en) * | 1971-07-01 | 1973-08-28 | M & T Chemicals Inc | Bright acid tin plating |
| DE4343585A1 (de) * | 1993-12-21 | 1995-06-22 | Bosch Gmbh Robert | Gehäuseanordnung und Verfahren zum Verschließen einer Gehäuseöffnung |
| CN113957495A (zh) * | 2020-07-21 | 2022-01-21 | 宝山钢铁股份有限公司 | 一种用于psa电镀锡不溶性阳极体系的光亮剂及应用 |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL134759C (enExample) * | 1968-10-16 |
-
1968
- 1968-11-07 US US774177A patent/US3577328A/en not_active Expired - Lifetime
-
1969
- 1969-11-07 DE DE1956144A patent/DE1956144C2/de not_active Expired
- 1969-11-07 FR FR6938521A patent/FR2022820A1/fr not_active Withdrawn
- 1969-11-07 JP JP44089227A patent/JPS4920703B1/ja active Pending
- 1969-11-07 SE SE15332/69A patent/SE362097B/xx unknown
- 1969-11-07 GB GB54688/69A patent/GB1263591A/en not_active Expired
-
1975
- 1975-12-30 MY MY119/75A patent/MY7500119A/xx unknown
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4880507A (en) * | 1987-12-10 | 1989-11-14 | Learonal, Inc. | Tin, lead or tin/lead alloy electrolytes for high speed electroplating |
| US5174887A (en) * | 1987-12-10 | 1992-12-29 | Learonal, Inc. | High speed electroplating of tinplate |
| WO2018219848A1 (en) | 2017-06-01 | 2018-12-06 | Basf Se | Composition for tin alloy electroplating comprising leveling agent |
| US11535946B2 (en) | 2017-06-01 | 2022-12-27 | Basf Se | Composition for tin or tin alloy electroplating comprising leveling agent |
Also Published As
| Publication number | Publication date |
|---|---|
| GB1263591A (en) | 1972-02-09 |
| DE1956144C2 (de) | 1982-11-04 |
| DE1956144A1 (de) | 1970-06-11 |
| FR2022820A1 (enExample) | 1970-08-07 |
| SE362097B (enExample) | 1973-11-26 |
| JPS4920703B1 (enExample) | 1974-05-27 |
| MY7500119A (en) | 1975-12-31 |
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