Classifications

• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
  • C25D3/00—Electroplating: Baths therefor
  • C25D3/02—Electroplating: Baths therefor from solutions
  • C25D3/56—Electroplating: Baths therefor from solutions of alloys
  • C25D3/58—Electroplating: Baths therefor from solutions of alloys containing more than 50% by weight of copper
• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
  • C25D3/00—Electroplating: Baths therefor
  • C25D3/02—Electroplating: Baths therefor from solutions
  • C25D3/56—Electroplating: Baths therefor from solutions of alloys
  • C25D3/60—Electroplating: Baths therefor from solutions of alloys containing more than 50% by weight of tin

Definitions

• the invention relates to a pyrophosphate-containing bath for the cyanide-free deposition of copper-tin alloys on substrate surfaces, which contains as an additive a reaction product of a secondary monoamine with a diglycidyl ether.
• the bath can be used to deposit cyanide-free homogeneous, lustrous copper-tin alloy layers whose alloying ratio can be adjusted selectively within the electrolyte, depending on the metal salt ratio used.
• Tin alloys and especially copper-tin alloys, have come into focus as an alternative to nickel deposits. Electrodeposited nickel layers are commonly used for both decorative and functional applications.
• Cyanide-containing copper-tin alloy baths are industrially established. Due to stricter regulations and the high toxicity and problematic and expensive disposal of these cyanide-containing baths, there is a growing demand for cyanide-free copper-tin electrolytes.
• JP 10-102278 A a pyrophosphate-based copper-tin alloy bath which contains as an additive a reaction product of an amine and an epihalodrin derivative (molar ratio 1: 1), an aldehyde derivative and, optionally, depending on the application, surfactants.
• the US 6416571 B1 also describes a pyrophosphate-based bath which also contains as additives a reaction product of an amine and an epihalohydrin derivative (molar ratio 1: 1), a cationic surfactant, optionally further surface-active surfactants and an antioxidant.
• a disadvantage of the abovementioned baths is that no uniform alloy layers are obtained, especially in the case of drum galvanizations, so that the products do not have a uniform coloring and gloss.
• a pyrophosphate-containing copper-tin alloy bath containing as an additive a reaction product of an amine derivative, more preferably piperazine, an epihalohydrin derivative, especially epichlorohydrin, and a glycidyl ether.
• an amine derivative more preferably piperazine
• an epihalohydrin derivative especially epichlorohydrin
• a glycidyl ether for the preparation of this reaction product, a mixture consisting of epichlorohydrin and the glycidyl ether is added slowly under precise temperature control to an aqueous solution of piperazine, wherein the temperature from 65 to 80 ° C must be maintained.
• this electrolyte exhibits weaknesses in rack plating applications.
• the quality of the deposited layers which often show a haze, very much depends on the nature of the movement of goods during the electrolysis.
• the copper-tin coatings obtained in this way also often have pores, which is problematic especially in decorative coatings.
• Example A-11 on page 26 of WO 2004/005528 describes the use of a reaction product of the diamine piperazine with ethylene glycol diglycidyl ether. This reaction product provides only matte white bronze layers.
• the invention is therefore based on the object to develop a plating bath for copper-tin alloys, which allows the production of optically attractive copper-tin alloy layers.
• the invention relates to a pyrophosphate-containing bath for the cyanide-free deposition of copper alloys on substrate surfaces, comprising a reaction product of a secondary monoamine with a diglycidyl ether.
• the secondary monoamines and the diglycidyl ethers can be used individually or in a mixture for the preparation of the reaction product.
• the secondary amine is morpholine.
• the digylcidyl ethers are glycerol diglycidyl ether, poly (ethylene glycol) diglycidyl ether, poly (propylene glycol) diglycidyl ether and mixtures thereof.
• a preferred reaction product for use in the bath of the invention is the reaction product of morpholine with glycerol diglycidyl ether.
• the organic additives can easily by reacting the corresponding amine components with the corresponding diglycidyl ethers in a suitable solvent, such as water, aqueous alcoholic solutions, aprotic solvents, such as ethers, NMP, NEP, DMF, DMAc or in bulk at room temperature or be displayed in the heat under normal or elevated pressure.
• a suitable solvent such as water, aqueous alcoholic solutions, aprotic solvents, such as ethers, NMP, NEP, DMF, DMAc or in bulk at room temperature or be displayed in the heat under normal or elevated pressure.
• a suitable solvent such as water, aqueous alcoholic solutions, aprotic solvents, such as ethers, NMP, NEP, DMF, DMAc or in bulk at room temperature or be displayed in the heat under normal or elevated pressure.
• aprotic solvents such as ethers, NMP, NEP, DMF, DMAc
• the reaction times required for this are between a few minutes and several hours,
• the resulting reaction products can be used directly, so that production in an aqueous medium or in bulk, the preferred method of preparation represents.
• the preferred temperatures of the preparation of the reaction products according to the invention are 15 to 100 ° C, particularly preferably 20 to 80 ° C.
• the molar ratios diglycidyl ether / amine are 0.8 to 2, more preferably 0.9 to 1.5. Particularly advantageous in these additives compared to the additive of WO 2004/005528 is the very simple production.
• reaction products according to the invention can be used alone or as a mixture of a plurality of different reaction products of the abovementioned type in a concentration of from 0.0001 to 20 g / l, preferably from 0.001 to 1 g / l and particularly preferably from 0.01 to 0.6 g / l become.
• the electrolyte baths according to the invention may contain copper pyrophosphate in a concentration of 0.5 to 50 g / l, with concentrations of 1 to 5 g / l being particularly preferred.
• the baths according to the invention may contain tin pyrophosphate in a concentration of 0.5 to 100 g / l, with concentrations of 10 to 40 g / l being particularly preferred.
• tin and copper pyrophosphates In addition to the above-mentioned tin and copper pyrophosphates, other water-soluble tin and copper salts, e.g. Tin sulfate, Zinnmethansulfonat, copper sulfate, copper methanesulfonate, are used, which can be umkomplexiert by addition of suitable alkali metal pyrophosphates within the electrolyte into the corresponding pyrophosphates.
• concentration ratio of pyrophosphate to tin / copper should be from 3 to 80, more preferably from 5 to 50.
• the alkali metal pyrophosphates optionally present in the baths according to the invention are particularly preferably the sodium, potassium and ammonium pyrophosphates in concentrations of 50 to 500 g / l, more preferably of 100 to 400 g / l.
• the antioxidants optionally present in the baths of the invention include hydroxylated aromatic compounds, e.g. Catechol, resorcinol, pyrocatechol, hydroquinone, pyrogallol, ⁇ - or ⁇ -naphthol, phloroglucin and sugar-based systems such as e.g. Ascorbic acid, sorbitol in concentrations of 0.1 to 1 g / l.
• hydroxylated aromatic compounds e.g. Catechol, resorcinol, pyrocatechol, hydroquinone, pyrogallol, ⁇ - or ⁇ -naphthol, phloroglucin
• sugar-based systems such as e.g. Ascorbic acid, sorbitol in concentrations of 0.1 to 1 g / l.
• alkylsulfonic acids both mono- and polysulfonic acids, e.g. Methanesulfonic acid, methanedisulfonic acid, ethanesulfonic acid, propanesulfonic acid, 2-propanesulfonic acid, butanesulfonic acid, 2-butanesulfonic acid, pentanesulfonic acid, hexanesulfonic acid, decanesulfonic acid, dodecanesulfonic acid and salts thereof and their hydroxylated derivatives are used. Particularly preferred is the use of methanesulfonic acid in a concentration of 0.01 to 1 g / l.
• the baths according to the invention have a pH of 3 to 9, more preferably 6 to 8.
• the additive according to the invention ie the reaction product of a secondary monoamine with a diglycidyl ether to deposit the alloy on the substrate with a uniform layer thickness with high gloss with a uniform distribution of the alloy components in the coating over a wide current density range. Furthermore, no pore formation occurs when the additive according to the invention is used. Finally, even with the Gestellgalvanmaschine fogging can be avoided.
• the aforementioned effects can be enhanced by the addition of N-methylpyrrolidone.
• the N-methylpyrrolidone is preferably used in a concentration of 0.1 to 50 g / l, more preferably 0.5 to 15 g / l.
• the baths according to the invention can be prepared by conventional methods, for example by adding the specific amounts of the above-described components to water.
• the amount of base, acid and buffer components, such as sodium pyrophosphate, methanesulfonic acid and / or boric acid, should preferably be selected so that the bath reaches the pH range of at least 6 to 8.
• the baths according to the invention deposit a bright, even and ductile copper-tin alloy layer at each customary temperature of about 15 to 50.degree. C., preferably 20.degree. C. to 40.degree. C., particularly preferably 20.degree. C. to 30.degree. At these temperatures, the baths according to the invention are stable and effective over a wide, adjusted current density range of 0.01 to 2 A / dm 2 , more preferably 0.25 to 0.75 A / dm 2 .
• the baths of the invention may be operated in a continuous or intermittent manner, and from time to time the components of the bath will have to be supplemented.
• the components of the bath may be added singly or in combination. Furthermore, they can be varied over a wide range, depending on the consumption and present concentration of the individual components.
• Table 1 shows, according to a preferred embodiment, the deposition results of the tin-copper alloy layers in the electrolytes according to the invention in comparison to electrolytes of the specification WO 2004/005528 , entry electrolyte Einges.
• Inventive electrolyte with additive A preparation and application example 1
• Electrolyte according to WO 2004/005528 Comparative Example 11, additive conc .: 10% by weight
• Electrolyte according to WO 2004/005528 Comparative Example 12, additive concentration: 1% by weight
• An advantage of the tin-copper baths according to the invention in comparison to the electrolyte of the WO 2004/005528 is the surprisingly low consumption of the additives of the invention compared to the reaction products of piperazine with epichlorohydrin and glycidyl ether.
• the aqueous baths according to the invention can generally be used for all types of substrates on which copper-tin alloys can be deposited.
• substrates on which copper-tin alloys can be deposited.
• useful substrates include copper-zinc alloys, chemically copper or chemically nickel-coated ABS plastic surfaces, mild steel, stainless steel, spring steel, chrome steel, chromium-molybdenum steel, copper and tin.
• Another object is therefore a process for the electrodeposition of copper-tin alloys on conventional substrates, wherein the bath according to the invention is used.
• the substrate to be coated is introduced into the electrolyte bath.
• the deposition of the coatings at a set current density of 0.25 to 0.75 A / dm 2 and at a temperature of 15 to 50 ° C, preferably 20 to 30 ° C.
• the method according to the invention can be carried out in the application for mass parts, for example as a drum electroplating method and for depositing on larger workpieces as a rack electroplating method.
• Anodes are used which can be soluble, such as copper anodes, tin anodes or suitable copper-tin alloy anodes, which serve as a copper and / or tin-ion source at the same time, so that on the Cathode deposited copper and / or tin is substituted by dissolving copper and / or tin at the anode.
• insoluble anodes e.g., platinized titanium mixed oxide anodes
• the copper and tin ions withdrawn from the electrolyte must be re-added in some other way, e.g. by addition of the corresponding soluble metal salts.
• galvanic deposition it is also possible to operate the process according to the invention under nitrogen or argon injection, with goods movement or without movement, without resulting in any disadvantages for the coatings obtained.
• the current source used are commercial DC converters or pulse rectifiers.
• An electrolyte with the following composition is used: 300 g / l tetrapotassiumpyrophosphate 3 g / l Copper pyrophosphate monohydrate 30 g / l pyrophosphate 40 ml / l Methanesulfonic acid 70% 12.5 ml / l 85% phosphoric acid 4 ml / l N-methylpyrrolidone 0.2 ml / l a 40% solution of one of the additives according to the invention according to an additive of Preparation Examples 1 to 10.

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)

Priority Applications (15)

Applications Claiming Priority (1)

Publications (2)

Family

ID=39831596

Family Applications (1)

Country Status (14)

Families Citing this family (12)

Family Cites Families (13)

• 2008
  • 2008-06-02 PL PL08010058T patent/PL2130948T3/pl unknown
  • 2008-06-02 EP EP08010058A patent/EP2130948B1/de not_active Not-in-force
  • 2008-06-02 DE DE502008002080T patent/DE502008002080D1/de active Active
  • 2008-06-02 AT AT08010058T patent/ATE492665T1/de active
  • 2008-06-02 ES ES08010058T patent/ES2354395T3/es active Active
  • 2008-06-02 SI SI200830180T patent/SI2130948T1/sl unknown
• 2009
  • 2009-05-29 KR KR1020107019214A patent/KR101609171B1/ko active IP Right Grant
  • 2009-05-29 CN CN2009801204709A patent/CN102046852B/zh not_active Expired - Fee Related
  • 2009-05-29 CA CA2724211A patent/CA2724211C/en not_active Expired - Fee Related
  • 2009-05-29 WO PCT/EP2009/003886 patent/WO2009146865A1/en active Application Filing
  • 2009-05-29 JP JP2011510900A patent/JP5735415B2/ja not_active Expired - Fee Related
  • 2009-05-29 US US12/866,996 patent/US20100326838A1/en not_active Abandoned
  • 2009-05-29 BR BRPI0912309 patent/BRPI0912309B1/pt not_active IP Right Cessation
  • 2009-06-01 TW TW098117986A patent/TWI441958B/zh not_active IP Right Cessation
• 2013
  • 2013-12-09 US US14/100,633 patent/US9399824B2/en not_active Expired - Fee Related

Also Published As

Similar Documents

Legal Events