Abstract: The invention relates to an acid tin-silver alloy plating bath which comprises tin ions, silver ions, one compound selected from the group consisting of aromatic thiol compounds and aromatic sulfide compounds, substantially non-cyanide and a balance of water, the pH of the bath being not higher than 2. According to this acid bath, tin and silver can be kept dissolved in the bath in a stable state for a long period of time even at a high temperature and a predetermined plating capacity is kept for a long period of time even though the bath is free from cyanide.

Abstract: A composition for water-repellent treatment of zinc and zinc alloys which comprises a non-ionic polymeric compound having both hydrophilic and hydrophobic groups in the molecule, a polyacrylic acid salt and a balance of water. The composition can be used in a method for water-repellent treatment of zinc and zinc alloys which comprises the steps of immersing zinc or zinc alloys which has been subjected to a conversion treatment, then washing it with water and drying the same. The use of the water-soluble composition for water-repellent treatments permits considerable reduction of the contact area between the repellent-treated metal material and moisture which becomes a cause of corrosion under the corrosive environment in which water and oxygen coexist and this accordingly results in the improvement in the corrosion-resistance of the metal material.

Abstract: An electrolytic conversion solution for metal surface treatment comprises (A) a vanadate or a vanadium salt of an inorganic acid and (B) an organic acid having a reducing ability, and has a pH of not less than 7. The electrolytic conversion solution can be employed in a method for electrolytic conversion treatment which comprises the steps of immersing a subject to be treated in the treating solution and then cathodically electrolyzing the subject in the solution. The electrolytic conversion solution is free of any chromate compound and permits the formation of uniform corrosion-resistant film on the surfaces of various kinds of metallic materials without impairing the working environment and causing any environmental pollution.

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 liquid rust proof film-forming composition comprises (A) an oxidative substance, (B) a silicate and/or silicon dioxide and (C) at least one member selected from the group consisting of metal cations of Ti, Zr, Ce, Sr, V, W and Mo; and oxymetal anions and fluorometal anions thereof. The composition can be used in a method for forming a rust proof film on a metal substrate which comprises the step of immersing the metal substrate in the composition. The composition and the methods form an excellent rust proof film on the surface of metal substrates without using any chemical substance harmful to environment such as hexavalent chromium.

Abstract: A black chromate-treatment solution for Zn-Ni alloy plated film comprises 1 to 100 g/l of hexavalent chromium, 1 to 100 g/l of hydrochloric acid residues and/or sulfuric acid residues, 1 to 100 g/l of nitric acid residues and 1 to 100 g/l of at least one metal selected from the group consisting of iron, nickel, cobalt and copper. The chromate-treatment solution permits the formation of a uniform black chromate conversion film on a Zn-Ni alloy plated film having an Ni content ranging from 8 to 20% by weight without using any silver ions in a substantial amount and the resulting black film is excellent in corrosion resistance.

Abstract: A Sn--Bi alloy plating bath comprises at least one compound selected from the group consisting of polyoxy monocarboxylic acids, polyoxy lactones, polycarboxylic acids and salts thereof. A plating method comprises the step of applying a Sn--Bi alloy plating film to a substrate in the foregoing plating bath. The plating bath permits the formation of a Sn--Bi alloy plating film having a bismuth content ranging from 0.1 to 75% over a wide current density range. Moreover, the plating bath never forms precipitates, does not become turbid, does not cause any change of the bath composition and is, therefore, quite stable even when it is stored over a long period of time.

Abstract: A deterring solvent essentially consists of (A) a brominated hydrocarbon of the formula: C.sub.n H.sub.2n+1 Br wherein n represents a number of 3 or above and/or a brominated hydrocarbon of the formula: C.sub.m H.sub.2m-1 Br wherein m represents a number of 2 or above. A deterging solvent composition comprises the above-described solvent (A) and a stabilizer selected from the group consisting of nitroalkanes, ethers, epoxides and amines. These solvent and solvent composition have an excellent deterging effect and usable as a substitute for the flon and chlorine solvents. Furthermore, the deterging solvent composition has a high stability.

Abstract: An admixture for cement comprises phosphorous acid and/or a salt thereof or a waste fluid originated from an electroless nickel-plating process which contains phosphorous acid and/or a salt thereof. The admixture is used as a setting accelerator, a rust proofing agent for reinforcing steel or a frost resistive agent for concrete and mortar as hydraulic cement blends. The admixture not only permits improvement of the resulting concrete in the setting-accelerating effect, but also can maintain the compressive strength at a high level while maintaining the bleeding rate at a low level.

Abstract: A zinc-iron-phosphorus alloy-plating bath having a pH of not less than 13 and containing iron, phosphorus and zinc sources in amounts required for electro-depositing a zinc-iron-phosphorus alloy film having an iron content ranging from 0.1 to 30% by weight, a phosphorus content ranging from 0.001 to 1.5% by weight and the balance of zinc, and an auxiliary agent for depositing phosphorus. The use of the alkaline plating bath permits the formation of a zinc-iron-phosphorus alloy film, through plating, excellent in lustre of deposit, throwing power and corrosion resistance and the reduction in corrosion of the plating equipment and also permits the formation of a film, through plating, having excellent adhesion as an undercoat for painting.

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: A zinc-cobalt alloy-plating alkaline bath comprises a zinc compound, a cobalt compound, an alkali hydroxide and a reaction product of an alkyleneamine with an alkylene oxide and having a pH of not less than 13 and a method for forming a zinc-cobalt alloy plating film comprises the step of forming, on a substrate, a zinc-cobalt alloy plating film having a cobalt content ranging from 0.05 to 20% by weight and a zinc content ranging from 80 to 99.95 % by weight, while using the foregoing alkaline plating bath. The Zn-Co alloy-plating bath permits the achievement of a desired rate of Co-eutectoid even when a small amount of a chelating agent is incorporated into the bath and therefore, the bath is excellent in the disposability of waste water.

Abstract: A chemically stable black chromate solution capable of forming an anticorrosive black chromate film on a Zn-Ni alloy plating is provided, the components being easily soluble in the solution. The black chromate solution comprises 1 to 50 g/l of hexavalent chromium; 1 to 50 g/l of sulfate ion; 0.05 to 1.0 g/l of soluble silver; 0.5 to 100 g/l of a sulfonated carboxylic acid selected from the group consisting of sulfo-aromatic carboxylic acids having 7 to 15 carbon atoms, sulfonated aliphatic dicarboxylic acids having 3 to 10 carbon atoms and salts thereof; and a balance of water, the solution having a pH of 0.5 to 2.5.

Abstract: A deterging solvent essentially consists of (A) a brominated hydrocarbon of the formula: C.sub.n H.sub.2n+1 Br wherein n represents a number of 3 or above and/or a brominated hydrocarbon of the formula: C.sub.m H.sub.2m-1 Br wherein m represents a number of 2 or above. A deterging solvent composition comprises the above-described solvent (A) and a stabilizer selected from the group consisting of nitroalkanes, ethers, epoxides and amines. These solvent and solvent composition have an excellent deterging effect and usable as a substitute for the flon and chlorine solvents. Furthermore, the deterging solvent composition has a high stability.

Abstract: An electroless plating solution comprises nickel ion, a chelating agent for nickel ion, dimethylamine borane, one or more soluble salts of a condensate of an arylsulfonic acid with formalin, and thiodiglycolic acid, and an electroless plating method comprises the step of immersing a substrate to be plated in this electroless plating solution for sufficent time period to form a nickel or nickel alloy layer on the substrate. The electroless plating solution has a high bath stability and is capable of forming an excellent thick deposit free from pits and cracks.

Abstract: A method for forming a ceramics film on the surface of a substrate comprises performing spark discharge in an electrolytic bath, wherein the electrolytic bath comprises an aqueous solution of a water-soluble or colloidal silicate and/or an oxyacid salt to which ceramics fine particles and/or specific fine particles are dispersed and the spark discharge is carried out in the electrolytic bath while ensuring the suspended state of the ceramics particles and/or the specific fine particles in the electrolytic bath. The method makes it possible to effectively form, on the surface of a metal substrate, ceramics films having a variety of color tones as well as excellent insulating properties and hardness. Moreover, it further makes it possible to effectively form a composite ceramics film having excellent wear resistance on the surface of a metal substrate.

Abstract: A method for forming a ceramic coating on a substrate comprises immersing the substrate such as stainless steel in an aqueous solution containing a silicic acid compound such as sodium silicate and/or a metal salt of oxygen acid such as an aluminate, and irradiating the substrate with a laser beam. By this method, a dense and fine ceramic coating can be uniformly formed on the substrate without using an apparatus of large scale required in the gas phase method and without heating the system to a high temperature.

Abstract: The invention provides an electroplating bath for forming a zinc-nickel alloy coating consisting essentially of water, about 1 to 70 grams/liter of zinc, about 0.6 to 118 grams per liter of nickel, at least one compound from the group consisting of (i) aliphatic amines in an amount not more than 16 grams/liter, (ii) polymers of aliphatic amines in an amount not more than about 20 grams per liter and (iii) a compound selected from the group consisting of hydroxyaliphatic carboxylic acids and salts thereof in an amount from 0 to 2 mols/liter, said bath having a pH of more than 11. The invention also provides an electroplating method for forming a chromate coating on a zinc-nickel alloy coating electrolytically deposited from the electroplating bath defined in the preceding sentence on electrically conductive metalics matrix material, and forming a chromate coating on the zinc-nickel alloy coating by means of a chromate treatment.

Abstract: An electroplating bath for depositing tin or a tin alloy with satisfactory brightness, which comprises a mother bath of a pH-value ranging from 4 to 8 and containing citric acid or its salt, an ammonium salt and a water-soluble polymer as a brightener. The bath may further comprise an aldehyde compound as a co-brightener.

Abstract: A method for stabilizing tin or tin alloy electroplating baths containing citric acid or its salt and an ammonium salt, by adding at least one saturated hydroxycarboxylic acid or its salt other than citric acid or citrate and/or at least one saturated dibasic carboxylic acid.