US3776740A - Electroless silvering composition and method - Google Patents

Electroless silvering composition and method Download PDF

Info

Publication number
US3776740A
US3776740A US00271380A US3776740DA US3776740A US 3776740 A US3776740 A US 3776740A US 00271380 A US00271380 A US 00271380A US 3776740D A US3776740D A US 3776740DA US 3776740 A US3776740 A US 3776740A
Authority
US
United States
Prior art keywords
silver
salt
reducer
acid
silvering
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00271380A
Other languages
English (en)
Inventor
C Sivertz
J Soltys
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
London Laboratories Ltd Co
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Application granted granted Critical
Publication of US3776740A publication Critical patent/US3776740A/en
Assigned to LONDON LABORATORIES LIMITED reassignment LONDON LABORATORIES LIMITED CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). Assignors: LONDON LABORATORIES LIMITED CO.
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
    • C23C18/16—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by reduction or substitution, e.g. electroless plating
    • C23C18/31—Coating with metals
    • C23C18/42—Coating with noble metals
    • C23C18/44—Coating with noble metals using reducing agents

Definitions

  • This invention relates to methods and compositions for the electroless deposition of metallic silver on various substrates.
  • An object therefore of the present invention is to provide new and improved silvering solutions and silvering methods which are less sensitive to process conditions such as high alkalinity, temperature lowering, and sequence of admixture of the reactive ingredients.
  • Another object is to provide new and improved silvering solutions and silvering methods which are more economical in the use of silver.
  • Another object is to provide new and improved silvering solutions and methods based upon a new class of reducing agents which are stable in highly alkaline medium.
  • a still further object of the invention is to provide new and improved methods of preparing silvering solutions, especially from concentrates of the ingredients, which take advantage of the stability of the reducers of the invention in strongly alkaline solutions, and which are not subject tothe explosive tendencies of known methods.
  • the invention accordingly comprises a composition of matter possessing the characteristics, properties and relation of components, as well as methods which comprise one or more steps and the relation of such steps, which composition and methods will be exemplified as hereinafter described, and the scope of the invention will be indicated in the claims.
  • an electroless silvering method of the invention comprises reactively contacting a water soluble silver composition, which contains silver in the ionic state, and a reducing agent which comprises an aldonic acid having 4 7 carbon atoms, or a salt or lactone of such aldonic acid, or mixtures of two or more of such acids, salts or lactones.
  • the invention pertains to a silvering solution comprising an aqueous medium containing a water soluble silver composition, in which silver is present in the ionic state, there also being present in the solution the aforementioned aldonic acid, salt, lactone or mixture, in an amount effective to induce reduction of the silver composition to metallic silver.
  • the invention includes methods of mixing the silvering solutions in which, contrary to usual practice, the reducing agent may be pre-mixed with one or more other reactants such as alkali before the final silvering solution is formed.
  • aldonic acid, salts and lactones of the invention are known compounds containing 4 7 carbon atoms inclusive.
  • acids the compounds may be represented by the following structure:
  • HOCH (CHOH), COOH where n is 2 5 inclusive.
  • aldotetronic acids the aldopentonic acids and the aldohexonic acids
  • the aldonic acids and lactones include the alpha and beta forms, where they exist, as well as the various optical isomers.
  • the aldopentonic acids include the D and L forms of arabinonic, ribonic, xylonic and lyxonic acids.
  • the aldohexonic acids include the D and L forms of gluconic, monnonic, galactonic, talonic, altronic, allonic, gulonic, and idonic acids.
  • the preferred salts of the acids are the water soluble salts including the alkali metal salts and ammonium or amino salts, such as sodium, potassium, and ammonium gluconate. Salts which have lesser degrees-of water solubility are useful although surfactants may be required to improve their dispersability.
  • aldohexonic and aldoheptonic acids are preferred.
  • Particularly preferred is gluconic acid, including its highly water soluble salts such as sodium gluconate, and its lactones such as glucono delta lactone and glucono gamma lactone.
  • Gluconic and glucoheptonic acids, their sodium salts, and especially glucono delta lactone are commercially available in high purity, such purity being an important consideration in the deposition of silver, for avoidance of streaks and the like.
  • the reducing agents of the invention include mixtures of one or more of such acids, salts and lactones.
  • any of the well known silver compounds or salts, inclusion complexes, coordination compounds (Werner complexes), and the like, will be effective provided the compositions have the requisite water solubility and interfering reactions are avoided.
  • the useful compositions may be mentioned the soluble silver salts such as silver nitrate and the like.
  • the preferred ionic silver composition is one in which the silver ion is complexed since not only is the solubility of the silver compound improved thereby, but also the tendency to precipitation of silver oxide with increase of pH is reduced.
  • Ammonia is the preferred complexing agent for these purposes and forms with silver nitrate the silver diammine ion, Ag (NH if desired, surfactants may be employed to further improve the water solubility of the silver composition.
  • a highly alkaline medium is desirable for acceptable rates of reaction.
  • a pH of at least about 12 will be suitable and preferably about 12.7 or higher. Since it is observed that the rate of reaction is proportionate to the alkalinity of the reaction medium, it is believed that the highly alkaline medium facilitates the transfer of electrons from the reducer to the silver ion.
  • the alkalinity is provided by any suitable means and preferably by the presence of a strong base such as an alkali metal hydroxide of which sodium hydroxide is representative.
  • the relative proportions of reactants in the silvering solutions of the invention may vary over a wide range.
  • the molar ratio of the reducer to the silver compound, such as silver nitrate will be about 1:1 to about 2:]. Below this range the quantity of silver deposited begins to decrease rapidly and above this range the quantity deposited is only marginally increased.
  • the ratio of silver salt to the other reactants may vary widely.
  • the weight ratio of strong base such as sodium hydroxide to silver salt such as silver nitrate is about 1:1.
  • the preferred ratio of hydroxyl ion to silver diammine ion is at about 4:1.
  • An amount of concentrated ammonia (28%) sufficient to form the silver diammine complex is also preferred to be present in the reaction mixture.
  • the other conditions for the preparation of the silvering solutions of the invention and the deposition of silver therefrom are not critical and may be varied as desired for optimum effects.
  • Such conditions include the manner of forming the silver diammine complex and the provision of the highly alkaline reaction medium.
  • the complex may be formulated by precipitating silver oxide from a solution of a soluble silver salt, such as silver nitrate, by reaction with a strong base such as sodium hydroxide, and then adding concentrated ammonium hydroxide (28%) until the last of the silver oxide passes into solution. A slight excess of ammonium hydroxide is added in order to compensate for evaporative losses which may occur prior to use of the silver solution.
  • the silver diammine complex may be formed directly from a silver salt by mixing the solution containing a soluble silver salt with the appropriate amount of concentrated ammonium hydroxide.
  • the strong base such as sodium hydroxide, may then be added to the solution or may be otherwise admixed as further explained below.
  • the stability of the new reducers of the invention in strong alkali makes possible several new ways of forming the component mixtures of the silvering solution as well as the final silvering solution itself.
  • the reducer comprises a separate solution which is added to a previously prepared solution of sodium hydroxide and ammoniacal silver nitrate shortly before or simultaneously with application of the final reaction mixture to the substrate upon which it is desired to deposit asilver film.
  • the ammoniacal silver nitrate may comprise a first solution and the strong base and reducer may comprise a second solution.
  • the two solutions are then admixed as required to deposit the silver.
  • a variation on this method is to provide a portion of the reducer in the first solution and the remainder in the second solution.
  • the reducer may be provided in a first solution with silver nitrate, and a second solution may contain the strong base and ammonium hydroxide complexing reagent. These two solutions are then admixed when it is desired to deposit the silver. Similar to the first method, a portion of the reducer may be present in each of these two solutions prior to admixture.
  • a known reducing agent for the electroless deposition of silver may be employed in conjunction with the reducers of the invention.
  • the conventional techniques for admixture of the reactants may be utilized with the exception that the known reducer, such as a carbohydrate compound, is present in the solution of the reducer of the invention.
  • the known reducer such as a carbohydrate compound
  • one solution may contain the conventional carbohydrate reducer
  • a second solution may contain the strong base and reducer of the invention
  • a third solution may contain the silver diammine reactant. in either case, upon admixture of the three solutions, silver is deposited as a coating.
  • the component solutions after their preparation are brought together just before contact with the substrate to be silvered.
  • This may be achieved in a variety of ways known to those skilled -in the art.
  • the component solutions may be poured or pumped such that they meet just before contact with the substrate.
  • the component solutions may be air-atomized prior to or simultaneously with intermixing at the surface of the substrate. Normally,
  • the behavior of the reducers of the invention in the presence of concentrations of alkali which decompose the commonly used reducers, is vastly different.
  • concentrations of alkali which decompose the commonly used reducers is vastly different.
  • the reducers of the invention are stable for long periods of time, 30 days or more in the case of gluconic acid.
  • the known aldose reducers decompose in minutes.
  • a wide variety of optional ingredients may be added to the silvering solution of the invention which essentially comprises the aqueous medium containing a water soluble ionic silver composition and reducing agent.
  • a strong base such as an alkali metal hydroxide, of which sodium hydroxide is representative.
  • modifiers for the purpose of buffering the solution, controlling the odor of the reaction mixture, or for preventing the deposition of sludge on the surface to be silvered.
  • the problem of preventing deposition of sludge is different in silvering processes than in the deposition of other m'etals such as copper and nickel.
  • reaction mixtures for the deposition of silver are far more reactive and difficult to control than reaction mixtures for the deposition of most other metals.
  • various complexing or chelating agents in concentrates for the electroless deposition of copper or nickel in order to prevent dispersion of colloidal aggregates of the metal throughout the entire reaction mixture since this would prevent deposition of the metal on the surface to be plated.
  • Such techniques are not normal in silvering due to the extreme reactivity of the solutions.
  • FIG. 1 is a chart comparing the amount of silver deposited using various reducing agents.
  • FIG. 2 is a graph comparing the amount of silver deposited using various reducing agentsatdifferent concentrations.
  • EXAMPLE 1 In the first of two separate tanks of400 liters each is I prepared an aqueous (distilled water) reducer solution containing glucono delta lactone at a concentration of 2.25 grams per liter. In the second tank is prepared an aqueous (distilled water) silver solution containing the ingredients and at the concentrations set forth in Table I:
  • This first method is a practical technique for the determination of the correct volume of concentrated ammonia to use with given concentrations of silver and sodium hydroxide, whatever the specific concentration of the ammonia.
  • the 2,000 grams of silver nitrate are first dissolved in about 300 liters of water. To this solution is then added concentrated ammonia, in the amount determined by the procedure of Example 1. This forms the silver complex ion first. Then the appropriate weight of sodium hydroxide, dissolved in 100 liters of pure water is added with stirring, to complete the solution. The two solutions are then applied to the surface to be silvered substantially as described above.
  • the concentrations set forth in Table I may be varied widely, depending on the nature of the surface to be silvered and other conditions, but for best results in most applications, the ratios of Table I should be approximately maintained. Some types of silvering are favored by a higher ratio of sodium hydroxide to silver nitrate than unity, in which case a determination of the volume of concentrated ammonia by the method described in Example 1 would be advisable to establish a formulation.
  • the present invention offers new ways of mixing the four essential components, with attendant special benefits.
  • new method D permits use of combined reducers, such as a known aldose carbohydrate type reducer, in tank 1, and a reducer of the invention, in tank 2.
  • a special benefit resulting from the use of new method C concerns the manufacture of antique mirrors, since this method permits silvering patterns not possible with a standard mix.
  • Methods B, C and D provide special advantages in the manual application of solutions for the deposition of silver on Christmas tree ornaments, in that these methods do not require an operator to mix sodium hydroxide with ammoniacal silver nitrate. Hence, the preparation of the solutions is very much less likely to produce accidental explosions.
  • EXAMPLE 4 The rate of deposition of silver from a reacting solution containing silver diammine ions, sodium hydroxide and a reducer was measured for a number of reducers. The variables were held constant throughout the experiments and only the reducer was varied. In each case, the following variables were maintained constant at the values recited:
  • EXAMPLE 6 The rate of deposition experiment of Example 4 was repeated in all essential respects except that the reducer tested was sodium heptagluconate, obtained from The Belzak Corporation of Clifton, NJ. as an aqueous solution wherein the major proportion of the heptagluconate was in the beta isomer form.
  • the test showed that the reducing efficiency by this reducer was similar to that of glucono delta lactone, while providing substantially the same advantages as glucono delta lactone in other respects, such as stability in the highly alkaline medium.
  • a method for the electroless deposition of metallic silver wherein a substrate is contacted with an aqueous alkaline medium containing a water soluble ionic silver composition capable of reduction to metallic silver and a reducer for said composition, the improvement which comprises providing as said reducer an effective amount of a compound selected from an aldonic acid having 4-7 carbon atoms, a salt of said aldonic acid, and a lactone of said aldonic acid.
  • a method according to claim 1 wherein said compound is gluconic acid, sodium gluconate, or glucono delta lactone.
  • said silver composition comprises ammoniacal silver nitrate.
  • a method according to claim 6 wherein said strong base is sodium hydroxide.
  • a silvering solution comprising an aqueous alkaline medium containing a water soluble ionic silver composition capable of reduction to metallic silver and a reducer for said composition, the improvement which comprises providing as said reducer an effective amount of a compound selected from an aldonic acid having 47 carbon atoms, a salt of said aldonic acid, and a lactone of said aldonic acid.
  • a silvering solution according to claim 8 wherein said compound is an aldohexonic or aldoheptonic acid, or a salt or lactone thereof.
  • a silvering solution according to claim 1 having a pH of at least l2.
  • a silvering solution according to claim 8 containing sodium hydroxide and silver nitrate, and having a pH of about 12 to about 12.7, wherein said ionic silver composition is silver diammine nitrate, said compound is gluconic acid, heptagluconic acid or the sodium salt thereof, the molar ratio of said compound to said silver nitrate is about 1:2 to about 1:1, the weight ratio of sodium hydroxide. to silver nitrate is about 1:1, and the molar ratio of hydroxyl ion to silver diammine ion is at least about 4:1.
  • a method of preparing a silvering solution which comprises:
  • a method of preparing a silvering solution which comprises:
US00271380A 1972-07-13 1972-07-13 Electroless silvering composition and method Expired - Lifetime US3776740A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US27138072A 1972-07-13 1972-07-13

Publications (1)

Publication Number Publication Date
US3776740A true US3776740A (en) 1973-12-04

Family

ID=23035315

Family Applications (1)

Application Number Title Priority Date Filing Date
US00271380A Expired - Lifetime US3776740A (en) 1972-07-13 1972-07-13 Electroless silvering composition and method

Country Status (5)

Country Link
US (1) US3776740A (de)
JP (1) JPS5427830B2 (de)
BE (1) BE795373A (de)
DE (1) DE2248693C3 (de)
FR (1) FR2193094B2 (de)

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3983266A (en) * 1974-10-09 1976-09-28 Peacock Laboratories, Inc. Method for applying metallic silver to a substrate
US4128671A (en) * 1973-03-14 1978-12-05 Reliance Electric Company Instant silvering solution
US4247303A (en) * 1974-09-04 1981-01-27 Inoue-Japax Research Inc. Method of forming an electrically conductive abrasive wheel
US4737188A (en) * 1987-05-18 1988-04-12 London Laboratories Limited Reducing agent and method for the electroless deposition of silver
EP0346954A2 (de) * 1988-06-17 1989-12-20 Pier Carlo Biginelli Verfahren zur Spritzmetallisierung von Formkörpern
US4965094A (en) * 1988-12-27 1990-10-23 At&T Bell Laboratories Electroless silver coating for dielectric filter
US5419926A (en) * 1993-11-22 1995-05-30 Lilly London, Inc. Ammonia-free deposition of copper by disproportionation
US6251482B1 (en) * 1994-05-12 2001-06-26 Glaverbel Forming a silver coating on a vitreous substrate
US6361824B1 (en) * 2000-07-31 2002-03-26 Nanocrystal Imaging Corp. Process for providing a highly reflective coating to the interior walls of microchannels
US20030172850A1 (en) * 2002-03-13 2003-09-18 Byong-Wa Chun Beneficiated water reducing compositions
US20040044257A1 (en) * 2000-10-21 2004-03-04 Cockman Russell William Process for the hydration of olefins
US6749307B2 (en) 1994-05-12 2004-06-15 Glaverbel Silver coated mirror
US20040265501A1 (en) * 2003-06-26 2004-12-30 Intel Corporation Preparation of electroless deposition solutions
US20060035018A1 (en) * 2002-11-01 2006-02-16 Advance Company, Ltd. Method for forming a thin film silver mirror and method for forming coated film comprising thin silver mirror film
US20070056464A1 (en) * 2005-09-14 2007-03-15 Bernards Roger F Solution and process for improving the solderability of a metal surface

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS49128819U (de) * 1973-03-08 1974-11-06
JPS5424093Y2 (de) * 1974-10-14 1979-08-16

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1209347A (en) * 1968-01-16 1970-10-21 Trans Metal Corp Method of electroless plating
US3582392A (en) * 1968-08-13 1971-06-01 Donald W Berman Method for preparing non-metallic surface for metallizing

Cited By (32)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4128671A (en) * 1973-03-14 1978-12-05 Reliance Electric Company Instant silvering solution
US4247303A (en) * 1974-09-04 1981-01-27 Inoue-Japax Research Inc. Method of forming an electrically conductive abrasive wheel
US3983266A (en) * 1974-10-09 1976-09-28 Peacock Laboratories, Inc. Method for applying metallic silver to a substrate
US4737188A (en) * 1987-05-18 1988-04-12 London Laboratories Limited Reducing agent and method for the electroless deposition of silver
EP0292087A2 (de) * 1987-05-18 1988-11-23 London Laboratories Limited Reduktionsmittel und Verfahren zur stromlosen Plattierung von Silber
EP0292087A3 (en) * 1987-05-18 1990-01-10 London Laboratories Limited Improved reducing agent and method for the electroless deposition of silver
AU594544B2 (en) * 1987-05-18 1990-03-08 Lilly Industries (Usa), Inc. Improved reducing agent and method for the electroless deposition of silver
EP0346954A3 (en) * 1988-06-17 1990-10-24 Pier Carlo Biginelli Process and apparatus for metal spraying of articles
EP0346954A2 (de) * 1988-06-17 1989-12-20 Pier Carlo Biginelli Verfahren zur Spritzmetallisierung von Formkörpern
US4965094A (en) * 1988-12-27 1990-10-23 At&T Bell Laboratories Electroless silver coating for dielectric filter
US5419926A (en) * 1993-11-22 1995-05-30 Lilly London, Inc. Ammonia-free deposition of copper by disproportionation
US6251482B1 (en) * 1994-05-12 2001-06-26 Glaverbel Forming a silver coating on a vitreous substrate
US6565217B2 (en) 1994-05-12 2003-05-20 Glaverbel Silver coated mirror
US6942351B2 (en) 1994-05-12 2005-09-13 Glaverbel Forming a silver coating on a vitreous substrate
US20040223238A1 (en) * 1994-05-12 2004-11-11 Pierre Laroche Forming a silver coating on a vitreous substrate
US6749307B2 (en) 1994-05-12 2004-06-15 Glaverbel Silver coated mirror
US6361824B1 (en) * 2000-07-31 2002-03-26 Nanocrystal Imaging Corp. Process for providing a highly reflective coating to the interior walls of microchannels
US20040044257A1 (en) * 2000-10-21 2004-03-04 Cockman Russell William Process for the hydration of olefins
WO2003078347A3 (en) * 2002-03-13 2004-02-12 Grace W R & Co Beneficiated water reducing compositions
US7048793B2 (en) 2002-03-13 2006-05-23 W.R. Grace & Co.-Conn. Beneficiated water reducing compositions
KR100919844B1 (ko) * 2002-03-13 2009-09-30 더블유. 알. 그레이스 앤드 캄파니-콘 선별된 감수성 조성물
US20050096280A1 (en) * 2002-03-13 2005-05-05 W.R. Grace & Co.-Conn. Beneficiated water reducing compositions
US6916369B2 (en) 2002-03-13 2005-07-12 W. R. Grace & Co.-Conn. Beneficiated water reducing compositions
US20030172850A1 (en) * 2002-03-13 2003-09-18 Byong-Wa Chun Beneficiated water reducing compositions
WO2003078347A2 (en) * 2002-03-13 2003-09-25 W.R. Grace & Co.-Conn Beneficiated water reducing compositions
US20060035018A1 (en) * 2002-11-01 2006-02-16 Advance Company, Ltd. Method for forming a thin film silver mirror and method for forming coated film comprising thin silver mirror film
US7087104B2 (en) * 2003-06-26 2006-08-08 Intel Corporation Preparation of electroless deposition solutions
US20040265501A1 (en) * 2003-06-26 2004-12-30 Intel Corporation Preparation of electroless deposition solutions
US20070056464A1 (en) * 2005-09-14 2007-03-15 Bernards Roger F Solution and process for improving the solderability of a metal surface
US7767009B2 (en) 2005-09-14 2010-08-03 OMG Electronic Chemicals, Inc. Solution and process for improving the solderability of a metal surface
US20110039019A1 (en) * 2005-09-14 2011-02-17 Bernards Roger F Solution and Process for Improving the Solderability of a Metal Surface
US8110252B2 (en) 2005-09-14 2012-02-07 Omg Electronic Chemicals, Llc Solution and process for improving the solderability of a metal surface

Also Published As

Publication number Publication date
BE795373A (fr) 1973-08-13
FR2193094B2 (de) 1976-11-05
DE2248693A1 (de) 1974-01-24
DE2248693C3 (de) 1985-03-21
JPS5427830B2 (de) 1979-09-12
JPS4936536A (de) 1974-04-04
FR2193094A2 (de) 1974-02-15
DE2248693B2 (de) 1979-12-20

Similar Documents

Publication Publication Date Title
US3776740A (en) Electroless silvering composition and method
US4737188A (en) Reducing agent and method for the electroless deposition of silver
US2762723A (en) Processes of chemical nickel plating and baths therefor
US4131699A (en) Method of preparation and use of electroless plating catalysts
US4180600A (en) Process using activated electroless plating catalysts
CN87102861A (zh) 化学镀铜及其镀浴
JPH0219190B2 (de)
US3983266A (en) Method for applying metallic silver to a substrate
US4780342A (en) Electroless nickel plating composition and method for its preparation and use
US3708329A (en) Electroless copper plating
SK283024B6 (sk) Spôsob pokovovania katalyticky aktivovaného povrchu meďou
US3915717A (en) Stabilized autocatalytic metal deposition baths
US4980035A (en) Bath for electrolytic deposition of a gold-copper-zinc alloy
US2976180A (en) Method of silver plating by chemical reduction
US3597267A (en) Bath and process for chemical metal plating
US3874897A (en) Activator solutions, their preparation and use in electroless plating of surfaces
GB2121444A (en) Electroless gold plating
US2883288A (en) Silver plating bath
US3767583A (en) Activator solutions their preparation and use in electroless plating of surfaces
US4978559A (en) Autocatalytic electroless gold plating composition
US2822294A (en) Chemical nickel plating processes and baths therefor
US4265942A (en) Non-noble metal colloidal compositions comprising reaction products for electroless deposition
US4180480A (en) Catalytically active compositions from precious metal complexes
US4273804A (en) Process using activated electroless plating catalysts
US3677776A (en) Electroless plating solutions for cadmium and cadmium copper alloys

Legal Events

Date Code Title Description
AS Assignment

Owner name: LONDON LABORATORIES LIMITED, ENGLAND

Free format text: CHANGE OF NAME;ASSIGNOR:LONDON LABORATORIES LIMITED CO.;REEL/FRAME:004074/0839

Effective date: 19820618

Owner name: LONDON LABORATORIES LIMITED

Free format text: CHANGE OF NAME;ASSIGNOR:LONDON LABORATORIES LIMITED CO.;REEL/FRAME:004074/0839

Effective date: 19820618