Abstract: The purpose of the present invention is to provide a palladium plating solution and a plating method for improving a bath stability of a palladium plating, without decreasing a deposition property of the palladium plating. A palladium plating solution for improving a bath stability, without decreasing a deposition property, comprising: an aqueous palladium compound: one or more complexing agent containing a compound having at least an ethylenediamine or a propylenediamine skeleton; a formic acid or a formate; and a sulfur compound, wherein the palladium plating solution is having two or more sulfide groups in a molecule of the sulfur compound.

Abstract: Disclosed herein are ink compositions for making a conductive palladium structure. For example, the ink composition can comprise a palladium salt and a complex of a complexing agent and a short chain carboxylic acid or salt thereof. In some embodiments, a second or third metal salt is included in the compositions. Also disclosed herein are methods for making and using such conductive ink compositions.

Abstract: The present invention concerns an electroless gold plating bath comprising a) gold ions; b) sulfite ions; c) iodide ions; d) at least one phosphonate compound according to formula (1) wherein each X is independently an alkanediyl group; R1, R2, R3 and each R4 are independently alkanediyl groups; M is independently hydrogen, a metal atom or a cation forming radical; each n is a rational number and selected in accordance with the valency of the respective M; and b is an integer ranging from 1 to 10. The invention further is directed to the use of the bath and a method for depositing a gold layer on a surface of a substrate. The bath is particularly suitable in the manufacture of printed circuit boards, IC substrates, semiconducting devices, interposers made of glass and the like.

Abstract: Aqueous acid binary silver-bismuth alloy electroplating compositions and methods enable electroplating silver rich binary silver-bismuth deposits. The aqueous acid binary silver-bismuth alloy electroplating compositions include thiol terminal aliphatic compounds having carboxyl or sulfonic groups which enable deposition of silver rich binary silver-bismuth alloys having deposits which are matte to semi-bright, uniform and have a low coefficient of friction.

Abstract: An electroless copper plating bath for depositing a copper or copper alloy layer on a surface of a substrate, including copper ions; a reducing agent; a complexing agent for copper ions; wherein the bath further includes at least one compound according to formula (1): in which Z1 and Z2 are independently selected from the group consisting of hydrogen; carboxylic acid; carboxylate; sulfonic acid; sulfonate; carboxamide; nitrile; nitro; trialkylammonium; 2-carboxyvinyl; 2-vinylcarboxylate; 2-(trialkylammonium)vinyl; hydroxamic acid; and oxime; provided at least one of Z1 and Z2 is not hydrogen; and in which R1, R2, R3 and R4 are: i. R1, R2, R3 and R4 are hydrogen; or ii. R1 with R2 form together an aromatic ring, R3 and R4 are hydrogen; or iii. R3 with R4 form together an aromatic ring, R1 and R2 are hydrogen; or iv. both R1 with R2 and R3 with R4 form together an aromatic ring, respectively.

Abstract: A decorative sheet manufacturing method of the present invention is for manufacturing a frosted glass-like decorative sheet using an inkjet printer including a head unit provided with a plurality of nozzles for jetting liquid droplets of an ultraviolet curable ink and an ultraviolet irradiation unit that moves together with the head unit in a main scanning direction of the head unit and irradiates the liquid droplets jetted from the nozzles and landed on a main surface of a transparent base material with ultraviolet rays, the frosted glass-like decorative sheet having the transparent base material and a plurality of dots formed in a print region on the main surface of the transparent base material and formed of a cured product of the ultraviolet curable ink by carrying out inkjet printing having predetermined printing conditions in a multi-pass manner.

Abstract: Silver-nickel alloy electroplating compositions and methods enable electroplating silver rich silver-nickel deposits which are bright, uniform and have a relatively low coefficient of friction. The binary silver-nickel alloy is deposited from an aqueous acid silver-nickel alloy electroplating composition. The aqueous acid silver-nickel alloy electroplating composition includes thiol compounds which shift the reduction potential of silver ions toward the reduction potential of nickel ions such that a silver rich binary silver-nickel layer is deposited on a substrate.

Abstract: A method for concurrently forming a first metal electrode (31, 58) on an n-type region of a silicon substrate (10) and a second metal electrode (32, 59) on a p-type region of the silicon substrate, wherein the n-type region and the p-type region are respectively exposed in a first and in a second area, is disclosed. The method comprises: depositing (101) an initial metal layer comprising Ni (33, 53) simultaneously in the first area and in the second area by a Ni immersion plating process using a plating solution; and depositing (102) a further metal layer (34, 54) on the initial metal layer comprising Ni (33, 53) in the first area and in the second area by an electroless metal plating process or by an immersion metal plating process, wherein the plating solution comprises Ni and a predetermined amount of another metal different from Ni.

Abstract: Cyanide-free acidic silver electroplating compositions include one or more acids or salts of tellurium and may be used to electroplate matte silver deposits on metals, such as nickel, copper or copper alloys. Matte silver metal may be electroplated at conventional plating rates or at high plating rates, such as in reel-to-reel and jet plating. The cyanide-free acidic silver electroplating compositions may be used to electroplate matte silver in the manufacture of electronic components such as electrical connectors, finishing layers for metallic substrates, optical devices and decorative applications.

Abstract: Provided herein is a method to printed electronics, and more particularly related to printed electronics on flexible, porous substrates. The method includes applying a coating compound comprising poly (4-vinylpyridine) (P4VP) and SU-8 dissolved in an organic alcohol solution to one or more surface of a flexible, porous substrate, curing the porous substrate at a temperature of at least 130° C. such that the porous substrate is coated with a layer of said coating compound, printing a jet of a transition metal salt catalyst solution onto one or more printing sides of the flexible, porous substrate to deposit a transition metal salt catalyst onto the one or more printing sides, and submerging the substrate in an electroless metal deposition solution to deposit the metal on the flexible, porous substrate, wherein the deposited metal induces the formation of one or more three-dimensional metal-fiber conductive structures within the flexible, porous substrate.

Abstract: To provide a near-infrared absorption composition capable of forming a film having excellent visible transparency and near-infrared shieldability, a cured film, a near-infrared absorption filter, a solid-state imaging device, and an infrared sensor. A near-infrared absorption composition includes a compound represented Formula (1) and a resin, the compound has a maximum absorption wavelength in a wavelength range of 750 to 830 nm in a film in a case where the film is formed using the near-infrared absorption composition, and a value obtained by dividing an absorbance at a wavelength of 555 nm by an absorbance at the maximum absorption wavelength is 0.10 or less.

Abstract: The invention relates to an aqueous plating bath composition and a method for depositing a palladium layer by electroless plating onto a substrate. The aqueous plating bath composition according to the invention comprises a source for palladium ions, a reducing agent for palladium ions and an unsaturated compound. The aqueous plating bath composition according to the invention has an improved stability against undesired decomposition due to the unsaturated compounds while keeping the deposition rate for palladium at the desired satisfying value. The aqueous plating bath composition has also a prolonged life time. The unsaturated compounds of the invention allow for adjusting the deposition rate to a satisfying range over the bath life time and for electrolessly depositing palladium layers at lower temperatures.

Abstract: There is provided an electrical contact member including: a conductive base material; and an Ag—Sn alloy plated layer formed on the conductive base material, wherein the Ag—Sn alloy plated layer has a first Ag—Sn alloy plated layer having an Sn concentration of 5 to 38 at. % and a Vickers hardness of 100 or more Hv and less than 300 Hv and a second Ag—Sn alloy plated layer having a Vickers hardness higher than that of the first Ag—Sn alloy plated layer in this order from the outermost layer.

Abstract: Electroless copper plating compositions including (a) copper ions, (b) a complexing agent for copper ions, (c) a reducing agent, (d) a pH adjustor and (e) a stabilizer is disclosed. The stabilizer has a specific chemical structure, and contributes to stable an electroless copper plating composition from decomposition.

Abstract: This invention relates to a conductive-coating bath comprising an aqueous solution containing (A) a copper compound, (B) a complexing agent, (C) an alkali metal hydroxide, (D) a C2-5 aliphatic polyalcohol compound, and (E) at least one compound selected from the group consisting of reducing compounds having a —COOM group, wherein M is hydrogen, an alkali metal, or a —NH4 group, and reducing saccharides having six or more carbon atoms. The present invention provides a composition for forming a conductive coating having excellent properties as a base layer for electroplating, which is effectively used to form a uniform decorative coating having excellent appearance by electroplating on a non-conductive plastic molding.

Abstract: A multilayer ceramic capacitor that includes a layered body in which dielectric layers and internal electrode layers are layered alternately, an external electrode on a surface of the layered body and a plating layer on a surface of the external electrode. The external electrode contains Cu, and a protective layer containing Cu2O is provided at a joining portion between the external electrode and the plating layer. When heat is applied to the layered body after the external electrode is removed, a ratio of an arithmetic mean value Xa of a quantity of hydrogen generated per unit temperature in a range higher than or equal to 350° C. with respect to an arithmetic mean value Y of a quantity of hydrogen generated per unit temperature in a range higher than or equal to 230° C. and lower than or equal to 250° C. (Xa/Y) is less than or equal to 0.66.

Abstract: An object of the present invention is to provide a novel conductive film-forming bath comprising an alkaline aqueous solution that can be used to form a film by electroplating on a non-conductive plastic material, the conductive film-forming bath being capable of forming a film by electroplating that has an excellent appearance and that does not suffer from reduced adhesiveness with respect to a non-conductive plastic material. The present invention relates to a conductive film-forming bath comprising an aqueous solution containing a copper compound, a complexing agent, an alkali metal hydroxide, and a water-soluble polymer having a polyoxyalkylene structure.

Abstract: The invention relates to a cyanide-free electrolyte composition for depositing a silver or silver alloy layer on a substrate as well as a method for depositing silver or silver alloy layers with a cyanide-free electrolyte composition. The electrolyte composition according to the invention comprises at least one silver ion source, a sulfonic acid and/or a sulfonic acid derivative, a wetting agent and a hydantoin. The silver or silver alloy layers deposited from the inventive electrolyte composition by the method according to the invention are dull and ductile.

Abstract: Optical sensing of trigger region incursion in the context of a firearm training system may be enhanced or otherwise improved through selective use of light absorbent materials within an optical detection range of one or more optical sensors. Surfaces located within a field of view of the optical sensor(s), such as interior facing surfaces of the trigger guard, surfaces of the trigger, and other surfaces located along the optical signal path may include light absorbent materials, such as dark surface colors, matte finishes, surface textures, and/or thin-film coatings that filter and/or absorb light of a particular wavelength or wavelength range.

Abstract: The invention relates to an electroless aqueous copper plating solution, comprising: a source of copper ions, a reducing agent or a source of a reducing agent, and a combination of complexing agents comprising i) polyamino disuccinic acid, polyamino monosuccinic acid, or a combination thereof, and ii) one or more of ethylenediamine tetraacetic acid, N?-(2-Hydroxyethyl)-ethylenediamine-N,N,N?-triacetic acid, and N,N,N?,N?-Tetrakis (2-hydroxypropyl)ethylenediamine, as well as methods for electroless copper plating utilizing the solution and uses of the solution for the plating of various substrates.

Abstract: The present invention relates to a method for direct metallization of non-conductive substrates as well as a conductor solution used in such a method. According to the invention, it is proposed to contact a non-conductive substrate surface after activation by a noble metal colloid-containing activator solution with a conductor solution, which comprises a metal that is reducible by a metal of the activator solution, a complexing agent and a reducing agent.

Abstract: The present invention relates to an electroless gold plating liquid, which may form gold plating without corrosion of a base metal by performing substitution and reduction reactions in the same bath, and satisfy both weldability of lead-free soldering and wire bonding characteristics, and has excellent stability such that a gold deposition rate may be continuously maintained.

Abstract: A method of depositing a silver layer includes forming a plurality of openings in a dielectric layer to expose a top surface of a structure comprising a resistive memory layer on top of a p-doped silicon-containing layer on top of a conductive structure, depositing a first metal layer comprising a tungsten layer overlying the top surface of the structure, wherein a first metal material of the first metal layer contacts a resistive memory material of the resistive memory layer and exposing the first metal layer in a bath comprising a solution of silver species having an alkaline pH for a predetermined time to form a silver metal layer from the silver species from the solution overlying the resistive memory material, wherein the silver species is reduced by the first metal material, and wherein the first metal material is solubilized while forming the silver metal layer.

Abstract: A method for manufacturing a test paper is disclosed in the present invention, and at least comprises the following steps. First, a chemical precursor comprising at least a reducing agent is coated onto a substrate. The substrate is then dipped into a metal salt solution comprising a plurality of metal ions for a predetermined time to reduce the metal ions to form metal particles on the substrate. Finally, the substrate is taken out and dried to complete a manufacture of at least a test paper. In the meantime a method for using the test paper, and a chemical composition used in the abovementioned for manufacturing the test paper are also disclosed in the present invention.

Abstract: A method for recombinantly expressing a macromolecule in a host cell is disclosed which involves culturing a host cell which contains two nucleic acid sequences, i.e., a first nucleic acid sequence encoding a membrane-permeabilizing agent and a second nucleic acid sequence encoding a desired macromolecule under the operative control of an inducible promoter, to a selected cell density that permits accumulation of the agent. Thereafter the host cell is exposed to an environmental condition that induces the agent to disrupt the integrity of the cell membrane without complete lysis of the cell membrane. The host cell thereby allows transport through the membrane of small molecular weight compounds. These resulting host cells are cultured in the presence of a nutrient cocktail that contains components that can transport through the disrupted cell membrane, e.g., an inducing agent that induces the tightly regulated promoter and metabolic requirements that permit expression of the macromolecule.

Abstract: A copper plating solution and a method for preparing a copper plating solution are provided. The copper plating solution comprises: a copper salt, a complexing agent, a stabilizer, a reducing agent, a surfactant, a hydroxyl-terminated polyoxypropylene ether, and a sodium trisulfide-isothiourea-propane sulfonate.

Abstract: The present invention relates to aqueous plating bath compositions for deposition of nickel and nickel alloys utilizing novel stabilising agents possessing a carbon-carbon triple bond and a functional group to enhance the bath performance.

Abstract: A copper plating solution and a method for preparing a copper plating solution are provided. The copper plating solution comprises: a copper salt, a complexing agent, a stabilizer, a reducing agent, a surfactant, a hydroxyl-terminated polyoxypropylene ether, and a sodium trisulfide-isothiourea-propane sulfonate.

Abstract: Provided is an electroless copper plating solution that forms a highly adhesive conductive film regardless of the degree of roughness of the resin surface and also has a fast deposition rate. The electroless copper plating solution of the present invention is characterized in that it contains guanosine. The electroless copper plating solution of the present invention preferably also contains copper ion, reducing agent, copper ion complexing agent, and pH adjuster.

Abstract: Provided is a coating solution where, upon producing a rare-earth superconductive composite metal oxide film by means of a coating-pyrolysis method, cracks are not generated in the heat treatment process for eliminating organic components, even when the thickness of the rare-earth superconductive film produced in a single coating is 500 nm or more, and without having to repeat the coating and annealing process. A solution for producing a rare-earth superconductive film which is made into a homogeneous solution by dissolving, in a solvent formed by adding a polyhydric alcohol to a univalent linear alcohol having a carbon number of 1 to 8 and/or water, a metal complex coordinated, relative to metal ions of a metallic species containing rare-earth elements, barium and copper, with pyridine and/or at least one type of tertiary amine, at least one type of carboxylic acid having a carbon number of 1 to 8, and, as needed, an acetylacetonato group.

Abstract: In particular, the present invention is directed processes and product related to blackened coatings, blackened electroless nickel coatings, blackened electroless nickel coatings including particulate matter, coatings with cover coats, coatings with voids, and the methods of application and products with such coatings.

Abstract: It is an object of the present invention to provide an electroless gold plating solution capable of directly subjecting a plated coating film made of an underlying metal such as nickel or palladium to gold plate processing, of forming a thick gold plated coating film having a thickness of 0.1 ?m or more, of forming a uniform gold plated coating film, and of safely performing plating work. The present invention relates to an electroless gold plating solution comprising: a water-soluble gold compound; and hexahydro-2,4,6-trimethyl-1,3,5-triazine or hexamethylenetetramine. Preferably, the electroless gold plating solution comprises 0.1 to 100 g/L of hexahydro-2,4,6-trimethyl-1,3,5-triazine or hexamethylenetetramine.

Abstract: One aspect of the present invention is a deposition solution to deposit metals and metal alloys such as for fabrication of electronic devices. According to one embodiment, the deposition solution comprises metal ions and a pH adjustor. The pH adjustor comprises a functional group having a general formula (R1R2N)(R3R4N)C?N—R5 where: N is nitrogen; C is carbon; and R1, R2, R3, R4, and R5 are the same or different and represent hydrogen, alkyl group, aryl group, or alkylaryl group. Another aspect of the presented invention is a method of preparing deposition solutions. Still another aspect of the present invention is a method of fabricating electronic devices.

Abstract: Compositions and methods for depositing elemental metal M(0) films on semiconductor substrates are disclosed. One of the disclosed methods comprises: heating the semiconductor substrate to obtain a heated semiconductor substrate; exposing the heated semiconductor substrate to a composition containing a metal precursor, an excess amount of neutral labile ligands, and a supercritical solvent; exposing the metal precursor to a reducing agent and/or thermal energy at or near the heated semiconductor substrate; reducing the metal precursor to the elemental metal M(0) by using the reducing agent and/or the thermal energy; and depositing the elemental metal M(0) film while minimizing formation of metal oxides.

Abstract: Provided are an electroless copper plating bath and an electroless copper plating method using the electroless copper plating bath, the electroless copper plating bath not containing formaldehyde; being usable under approximately neutral pH conditions; improving plating bath stability; and capable of forming a plating film with a good thickness while controlling deposition outside a pattern. The electroless copper plating bath according to the present invention contains a water-soluble copper salt, and amine borane or a substituted derivative thereof as a reducing agent; does not contain formaldehyde; and has a pH of 4 to 9, wherein polyaminopolyphosphonic acid as a complexing agent, an anionic surface-active agent, an antimony compound, and a nitrogen-containing aromatic compound are contained.

Abstract: Solutions and processes for electrodepositing gallium or gallium alloys includes a plating bath free of complexing agents including a gallium salt, an indium salt, a combination thereof, and a combination of any of the preceding salts with copper, an acid, and a solvent, wherein the pH of the solution is in a range selected from the group consisting of from about zero to about 2.6 and greater than about 12.6 to about 14. An optional metalloid may be included in the solution.

Abstract: A method for forming electrical traces on a substrate includes the steps of: providing a substrate; printing an ink pattern using an ink on the substrate, the ink including a aqueous medium containing silver ions and a heat sensitive reducing agent; heating the ink pattern to reduce silver ions into silver particles thereby forming an semi-finished traces; and forming a metal overcoat on the semi-finished traces by electroless plating thereby obtaining patterned electrical traces.

Abstract: A production method of composite silver nanoparticle including the steps of: arranging at least an alcohol solvent selected from alcohols with a carbon number of 1 to 12 composed of methanol, ethanol, propanol, buthanol, pentanol, hexanol, heptanol, octhanol, nonanol, decanol, undecanol and dodecanol; preparing an alcohol solution by mixing a silver salt into the alcohol solvent added more excessively than the mol number of the silver salt so as to become an excess alcohol solution; heating the excess alcohol solution in a reaction chamber at a generation temperature PT generating an aldehyde for a generation time; forming a silver core through reducing of the silver salt by the alcohol solvent and/or the aldehyde; and forming a composite silver nanoparticle having an organic coating layer originated from the alcohol solvent around the silver core.

Abstract: The present invention provides compositions and processes for preparing metallic ions for deposition on and/or into conductive substrates, such as metals, to substantially eliminate friction from metal to metal contact. It is used in the aqueous embodiment to form new metal surfaces on all metal substrates. The processes form stable aqueous solutions of metal and metalloid ions that can be adsorbed or absorbed on and/or into conductive substrates. The aqueous solutions consist of ammonium alkali metal phosphate salts, and/or ammonium alkali metal sulfate salts mixed with a water soluble metal or metalloid salt from Group I through Group VIII of the periodic table of elements. The aqueous solutions allow for a nano deposition of the metal ions on and/or into the surfaces of conductive substrates. The surfaces created by the deposited metal ions will provide metal passivation and substantially eliminate friction in metal-to-metal contact without the use of hydrocarbon based lubricants.

Abstract: A non-aqueous electroless copper plating solution that includes an anhydrous copper salt component, an anhydrous cobalt salt component, a non-aqueous complexing agent, and a non-aqueous solvent is provided.

Abstract: The present invention provides a displacement gold plating solution and a plating treatment technology capable of realizing a uniform film thickness when forming a connecting portion obtained by sequentially plating a nickel layer, a palladium layer, and a gold layer in layers. The present invention provides a displacement gold plating solution for forming a connecting portion obtained by sequentially plating a nickel layer, a palladium layer, and a gold layer in layers on a conductor layer containing a conductive metal. The displacement gold plating solution contains a gold cyanide salt, a complexing agent, and a copper compound. A molar ratio of the complexing agent and the copper compound in the displacement gold plating solution is in a range of complexing agent/copper ion=1.0 to 500. A compound formed from the complexing agent and the copper compound has a stability constant of 8.5 or higher at a pH of between 4 and 6.

Abstract: A non-aqueous electroless copper plating solution that includes an anhydrous copper salt component, an anhydrous cobalt salt component, a non-aqueous complexing agent, and a non-aqueous solvent is provided.

Abstract: Disclosed is an electroless plating solution exhibiting a good plating metal filling performance even for larger trenches or vias of several to one hundred and tens of ?m, in a manner free from voids or seams, and allowing maintenance of stabilized performance for prolonged time. The electroless plating solution contains at least a water-soluble metal salt, a reducing agent for reducing metal ions derived from the water-soluble metal salt, and a chelating agent. In addition, the electroless plating solution contains a sulfur-based organic compound as a leveler having at least one aliphatic cyclic group or aromatic cyclic group to which may be linked at least one optional substituent. The aliphatic cyclic group or the aromatic cyclic group contains optional numbers of carbon atoms, oxygen atoms, phosphorus atoms, sulfur atoms and nitrogen atoms.

Abstract: An alkalescent chemical silver electroless plating solution, which comprises: 0.01˜20 g/L silver ion or silver complex ion, 0.1˜150 g/L amine complexing agent, 0.1˜150 g/L amino acids complexing agent, and 0.1˜150 g/L polyhydroxy acids complexing agent. The alkalescent chemical silver plating solution provided by the present invention is able to overcome problems existing in acidic chemical silver plating processes commonly used at present. These problems include gnawing and corrosion of copper wires, lateral corrosion and difficulty of plating silver in blind holes, presence of solder ball voids and low strength of soldering. The silver layer plated by said silver plating solution possesses characteristics of high corrosion resistance, low contact resistance, no electromigration, high welding strength, and avoidance of bubbles produced in the solder when the plating pieces are being welded.

Abstract: Described is a new process for applying a metal coating to a non-conductive substrate comprising the steps of (a) contacting the substrate with an activator comprising a noble metal/group IVA metal sol to obtain a treated substrate, (b) contacting said treated substrate with a composition comprising a solution of: (i) a Cu(II), Ag, Au or Ni soluble metal salt or mixtures thereof, (ii) 0.05 to 5 mol/l of a group IA metal hydroxide and (iii) a complexing agent for an ion of the metal of said metal salt, wherein an iminosuccinic acid or a derivative thereof is used as said complexing agent.

Abstract: This invention is directed to a process for electrolessly metallizing an article, as well as to a plating bath and the subsequent plated substrate. The process comprises contacting the surface of an article with an electroless metallizing bath which may be essentially free of toxic and/or heavy metals.

Abstract: Disclosed is an electroless plating solution exhibiting a good plating metal filling performance even for larger trenches or vias of several to one hundred and tens of ?m, in a manner free from voids or seams, and allowing maintenance of stabilized performance for prolonged time. The electroless plating solution contains at least a water-soluble metal salt, a reducing agent for reducing metal ions derived from the water-soluble metal salt, and a chelating agent. In addition, the electroless plating solution contains a sulfur-based organic compound as a leveler having at least one aliphatic cyclic group or aromatic cyclic group to which may be linked at least one optional substituent. The aliphatic cyclic group or the aromatic cyclic group contains optional numbers of carbon atoms, oxygen atoms, phosphorus atoms, sulfur atoms and nitrogen atoms.

Abstract: An electroless gold plating bath includes a water-soluble gold compound, a complexing agent, an aldehyde compound, and an amine compound represented by R1—NH—C2H4—NH—R2 or (CH2—NH—C2H4—NH—CH2)n—R4 (wherein R1 to R4 represent —OH, —CH3, —CH2OH, —C2H4OH, —CH2N(CH3)2, —CH2NH(CH2OH), —CH2NH(C2H4OH), —C2H4NH(CH2OH), —C2H4NH(C2H4OH), —CH2N(CH2OH)2, —CH2N(C2H4OH)2, —C2H4N(CH2OH)2 or —C2H4N(C2H4OH)2, and n is an integer of 1 to 4). The electroless gold plating can be carried out without corrosion of an underlying metal to be plated at a stable deposition rate. Because of the high deposition rate and the immersion and reduction types, thickening of a plated coating is possible in one solution and the color of the coating is not degraded to provide a good appearance while keeping a lemon yellow color inherent to gold.

Abstract: An electroless gold plating bath includes a water-soluble gold compound, a complexing agent, a formaldehyde metabisulfite adduct, and an amine compound represented by R1—NH—C2H4—NH—R2 or (CH2—NH—C2H4—NH—CH2)n—R4 (wherein R1 to R4 represent —OH, —CH3, —CH2OH, —C2H4OH, —CH2N(CH3)2, —CH2NH(CH2OH), —CH2NH(C2H4OH), —C2H4NH(CH2OH), —C2H4NH(C2H4OH), —CH2N(CH2OH)2, —CH2N(C2H4OH)2, —C2H4N(CH2OH)2 or —C2H4N(C2H4OH)2, and n is an integer of 1 to 4). A gold plated coating of a good appearance can be formed without causing a failure in appearance owing to the progress of intergranular corrosion in a nickel surface.

Abstract: A method for enhancing the solderability of a metallic surface is disclosed where the metallic surface is plated with an immersion silver plate prior to soldering, which immersion silver plate is treated with an additive selected from the group consisting of fatty amines, fatty amides, quaternary salts, amphateric salts, resinous amines, resinous amides, fatty acids, resinous acids, ethoxylated derivatives of any of the foregoing, and mixtures of any of the foregoing. The immersion silver deposits created are resistant to electromigration.