Abstract: The present invention relates to composite articles including a surface layer of tin, lead, silver or an alloy thereof that contains co-deposited non-ionic polymeric particles to provide a reduced-friction deposit that has an initially low coefficient of friction and low insertion force and fretting corrosion in separable electronic connectors, and to methods for preparing the plated articles. The polymeric particles have a size between about 0.1 to 0.45 .mu.m in diameter to reduce the coefficient of friction of the resultant deposit to about 0.45 or below. Also, the deposit has excellent electrical properties and can be successfully soldered. The invention also relates to a solution for plating the surface layer of the composite articles, which surface layer reduces insertion force and fretting corrosion of separable electronic connectors.

Abstract: An Sn--Bi alloy-plating bath comprises (i) Bi ions, (ii) Sn ions, (iii) ions of one metal selected from the group consisting of Cu, Co and Ag, and (iv) one member selected from the group consisting of carboxylic acids, lactone compounds, alkanesulfonic acids, alkanolsulfonic aicds, phenolsulfonic acids and salts thereof and is substantially free of lead ions. The bath permits the formation of an Sn--Bi alloy-plated film, does not form any plated film having impaired quality even at a temperature higher than about 100.degree. C. and does not form any whisker.

Abstract: A process for plating tin or tin alloy onto metal substrates is described. In the process, a metal substrate is placed in an electroplating bath that contains a stannous sulfate and an organic compound additive in which the organic compound has a heterocyclic moiety in an aqueous solution of sulfonic acid. The bath is then subjected to pulse plating conditions that plate a layer of tin or tin alloy onto the metal substrate wherein the tin in the tin layer has a grain size of about 2 .mu.m to about 8 .mu.m. During pulse plating, a current density of about 65 ASF to about 250 ASF is applied to the electroplating bath in a pulsed manner, i.e. the current is cycled on and off during plating. The duty cycle of the pulse is about twenty-five percent to about thirty percent. The duration of the on pulse during the cycle is about 50 .mu.s to about 500 .mu.s.

Abstract: It now has been found that a smooth and level deposit of tin, lead or tin-lead alloy can be deposited on a substrate from an aqueous plating bath which comprises (A) at least one bath-soluble metal salt selected from the group consisting of a stannous salt, a lead salt, or a mixture of stannous and lead salts, (B) an acid selected from the group consisting of sulfuric or fluoboric acid; and (C) an effective amount of at least one soluble bismuth salt of an alkane sulfonic acid or an alkanol sulfonic acid. Optionally, the aqueous plating bath may further comprise (D) at least one surfactant.

Abstract: The present invention relates to a solution and method for plating tin, lead, or tin-lead alloy deposits which contain a co-deposit of fluorocarbon particles to provide a lower-friction solder-type deposit which reduces insertion force and fretting corrosion in separable electronic connectors. The fluorocarbon particles have a size between about 0.1 to 1 .mu.m in diameter, and reduce the coefficient of friction of the resultant deposit to 0.8 or less. Also, the deposit has excellent mechanical properties and can be successfully soldered.

Abstract: An electroplating solution (A), comprises an aqueous solution consisting essentially of lead phenolsulfonate: 1 to 250 g/liter in terms of Pb content; tin phenolsulfonate: 0.1 to 250 g/liter in terms of Sn content; phenolsulfonic acid: 20 to 300 g/liter; polyoxyethylene polyoxypropylene alkylamine: 1 to 50 g/liter; a 1-naphthaldehyde derivative: 0.001 to 1 g/liter; and an aldol sulfanilic acid derivative: 0.1 to 30 g/liter; or an aqueous solution (B) consisting essentially of lead methanesulfonate: 1 to 250 g/liter in terms of Pb content; tin methanesulfonate: 0.1 to 250 g/liter in terms of Sn content; methanesulfonic acid: 20 to 300 g/liter; polyoxyethylene polyoxypropylene alkylamine: 1 to 50 g/liter; and an aldol sulfanilic acid derivative: 0.1 to 30 g/liter.

Abstract: A tin-zinc alloy electroplating bath comprises an amphoteric surfactant, a water-soluble stannous salt, a water-soluble zinc salt and a balance of water. When the tin-zinc alloy plating bath of the present invention is used, the formed coating film comprises a uniform alloy composition even in case where the current density varies over a wide range. Therefore, the coating film having the uniform alloy composition can be formed even on the substance having a complicated shape and the chromate treatment becomes satisfactory. As a result, the effect of the coating is improved, the resultant product is stable and the productivity is improved. Thus the tin-zinc alloy coating film having a high quality can be provided.

Abstract: In order to produce bright to brilliant, leveled copper-tin alloy coatings, galvanic baths are used which contain 1 to 60 g/l copper in the form of copper(I) cyanide, 1 to 50 g/l tin in the form of alkali stannate, 0 to 10 g/l zinc in the form of zinc cyanide, 1 to 200 g/l of one or several complex binders (e.g., oligosaccharides and/or polysaccharides), 1 to 100 g/l free alkali metal cyanide, 1 to 50 g/l free alkali metal hydroxide, 0 to 50 g/l alkali metal carbonate 0.01 to 5 g/l brightener (e.g., alkene sulfonate, alkyne sulfonate, pyridine compounds or sulfur-containing propane sulfonates) and 0 to 100 mg/l lead as lead(II) acetate or lead(II) sulfonate.

Abstract: The present invention relates to a novel composition of matter, and a process for its use as an electroplating additive for enhancing the performance of a plating bath. Polyalkylene glycol bis-phenyl-A-Sulfopropyl diether compounds and their salts are proposed and their usefulness as plating bath additives is disclosed.

Abstract: Silver-tin alloys can be deposited by the galvanic method from a cyanide-free bath which is prepared using silver as the nitrate or diammine complex, tin as the soluble tin(II) or tin(IV) compound and mercaptoalkane-carboxylic acids and -sulfonic acids, Uniform and adhering coatings of silver-tin alloys with a silver content of approximately 20 to 99 weight % can be deposited from said bath. Silver-tin alloys are electrodeposited from said bath at a pH of 0 to 14 and a current density of 0.1 to 10 A/dm.sup.2.

Abstract: The present invention relates to a solution for use in the electroplating of tin and tin alloys comprising a basis solution which includes fluoboric acid or an organic sulfonic acid or one of their salts, divalent tin ions, and an antioxidant compound which includes a transition metal selected from the elements of Group IV B, V B or VI B of the Periodic Table in an amount effective to assist in maintaining the tin ions in the divalent state. Another aspect of the invention relates to a method for preventing, reducing or minimizing the oxidation of tin ions in an acid electroplating solution by adding one of these antioxidant compounds thereto. This method is effective in certain basis solutions even when iron contamination or high oxygen levels are present.

Abstract: New formulations for the electrodeposition of a dense, reflective tin or tin-lead alloy on a cathode have been developed. Such electrodeposition solutions are partially comprised of an additive which is comprised of at least one nonionic surfactant which is electrolyzed prior to starting the electrodeposition process. The electrodeposition solution is also comprised of an amount of an aliphatic dialdehyde kept low enough so that the solder deposits contain no more than 500 ppm of co-electrodeposited carbon. The additive and the aliphatic dialdehyde is mixed with a solution comprised of an alkane or alkanol sulfonic acid and a tin alkane or alkanol sulfonate or a mixture of a tin and lead alkane or alkanol sulfonate to form an electrodeposition solution. A dense, reflective finish is then electrodeposited on a cathode by using such an electrodeposition solution.

Abstract: The formation of whiskers during tin or tin-lead solder electroplating of a copper base alloy substrate in a methane sulfonate solder plating bath is inhibited by passivating the surface of the substrate prior to electroplating. Preferred passivating solutions include an aqueous solution of sodium dichromate and phosphoric acid, and an aqueous solution of chromic acid and phosphoric acid. Passivation is preferably followed by treatment with a basic solution having a pH of at least 8.

Abstract: This invention relates to additives for methanesulfonic acid based tin and tin alloy plating formulations. Specifically, the invention involves the use of gallic acid in the multiple roles of antioxidant, grain refiner, selective precipitant, and selective chelator in methanesulfonic acid based tin or tin alloy plating formulations.

Abstract: Baths and methods for the electroplating of tin, tin-lead, tin-antimony, and/or tin-bismuth are described. Specifically, electrodeposition solutions, based on alkanesulfonic acids, soluble metal salts, other additives, and at least one nonionic surfactant terminated with a ketone group, have been developed. The use of ketone (e.g., --OCH.sub.2 COCH.sub.3) terminated polyoxyalkylene surfactants results in electrodeposition solutions with reduced foam, and the tin and tin alloy electrodeposits from such plating baths are of superior quality.

Abstract: A system for electroplating a tin-bismuth alloy at near eutectic composition is disclosed. The system includes the plating bath and the process for initially preparing the bath as well as the process for plating an object with tin-bismuth alloy. The system further includes an apparatus for regulating the concentrations of tin and bismuth in the plating bath and the process by which the concentrations are controlled.

Abstract: The invention provides a bath for immersion plating a substance with a tin-lead alloy, which includes tin(II) ions, lead(II) ions, organic sulfo groups and thiourea or a mixture of thiourea and a thiourea derivative for a complexing agent. The organic sulfo groups allow insoluble thiourea complexes to be stably dissolved in the solution of the bath; thereby there is no need to retain the bath at a high temperature. Compared with conventional baths for immersion plating, the bath of the invention attains stable plating and a longer life of itself. Addition of the thiourea derivative prevents whiskers from being deposited and allows uniform and sufficiently smooth plating.

Abstract: This invention relates to alkyl and alkanol sulfonic acid plating baths and to methods for plating tin and tin-lead alloys. It also relates to low foaming wetting systems based on low to moderate foaming surfactants and soluble, non-silicon containing defoamers, and to low volatility brightener systems.

Abstract: Baths and methods for electroplating tin or tin-lead alloys wherein the formation of tetravalent tin and stannic oxide sludge is reduced or prevented. These baths contain a soluble divalent tin compound, a soluble alkyl or alkylol sulfonic acid at least one wetting agent, and a hydroxyl phenyl compound reducing agent. Other compounds may be added to the bath for improving its performance during electroplating.