Showing papers on "Sodium hypophosphite published in 1994"

Electrochemically Deposited Diffusion Barriers

Abstract: Diffusion barrier properties of electrochemically deposited Ni, Co, and Ni‐Co alloys were examined in the binary system and the Au/Ni/Cu ternary system. Ni and Co were electrodeposited from sulfate or sulfamate (Ni) solutions in the presence of boric acid, at pH 3.30. Electroless Ni and Co deposited either from sulfate or sulfamate solution using sodium hypophosphite or dimethylamine borane as the reducing agent. Electroless gold was deposited from cyanide solutions using potassium borohydride as the reducing agent. The deposits were annealed at 400°C for 14 h in a forming gas atmosphere (10% , 90% ). Auger electron spectroscopy and electron probe analysis were used to assess the extent of interdiffusion as a result of the heat‐treatment. Only electrolessly deposited 1000 A thick Ni, Co, and Ni‐Co alloys have barrier properties for Cu diffusion. For 1000 A thick barriers, annealed for 14 h, the amount of the interdiffused copper into was less than 1 atomic percent. Thicker barriers of , , and are required for the same degree of Cu diffusion. thin films deposited from nickel sulfamate solutions are better diffusion barriers than those deposited under the same experimental conditions, from nickel sulfate solutions. Electrochemically deposited barriers were compared with Ni, Co, and Cr barriers produced by evaporation. The differences between the diffusion barrier properties of deposited from the sulfamate and the sulfate solutions were interpreted in term of microstructural data and grain growth mechanism.

Non-formaldehyde durable press finishing for cellulosic textiles with phosphinocarboxylic acid

Abstract: A composition and method for providing a non-formaldehyde durable press finish to cellulosic fabrics by employing polyphosphinocarboxylic acids are disclosed. The polyphosphinocarboxylic acid is preferably polyphosphinoacrylic acid, and is optimally used in combination with phosphonoalkylpolycarboxylic acid, and, for cost effectiveness, a low-cost polycarboxylic acid such as citric acid. The catalyst for the curing reaction is preferably a phosphorus-containing acid or alkali metal salt thereof such as a mixture of sodium monophosphate and sodium hypophosphite.

Catalytic Properties of Nickel Catalysts, for Methanol Decomposition, on Aluminum Plate Prepared by Electroless Plating

Abstract: In order to obtain a tube-wall reactor with high thermal conductivity, nickel catalysts on an aluminum plate were prepared by electroless plating which consisted of displacement of aluminum by zinc and the deposition of nickel by chemical reduction. Thus plated catalysts showed high activities and high selectivities when forming carbon monoxide and hydrogen by methanol decomposition. The catalytic properties of the plated catalysts were significantly affected by the plating conditions. In particular, the plated catalyst prepared using an alkaline zinc plating bath and the neutral nickel plating bath that included sodium hypophosphite as the reducing agent had the highest activity and the highest selectivity. It was also shown that the displacement operation and the use of the nickel plating bath including a reducing agent was important factors forming a uniform plated layer having strong adhesion to the aluminum base.

Electrodeposition of amorphous iron-nickel-phosphorus alloy coatings

Abstract: SUMMARYThe effects of plating parameters on the composition and structure of electrodeposited Fe-Ni-P alloys have been studied. A sulfate electrolyte containing sodium hypophosphite with an acetate buffer was used. Deposits were plated onto both planar and rotating cylinder electrodes. Alloy deposits that were amorphous over a wide range of iron:nickel ratios were achieved. The anomalous deposition typical of Ni-Fe alloy plating was not observed in these studies where phosphorus was codedeposited. The deposit composition was dependent on both the plating bath composition and current density.

Antifungal fungiproof gypsum board

Abstract: PURPOSE:To give antifungal and fungiproof property to a gypsum board and to effectively use an old liquid of electroless nickel plating liquid which is wasted in a large amt., by compounding a hardly-soluble phosphite into the gypsum board. CONSTITUTION:(A) A gypsum material such as gypsum anhydride, gypsum hemihydrate or gypsum dihydrate, (B) hardly-soluble metal phosphite by 0.5-30wt.% of the gypsum board to be produced, and if necessary, (C) a proper amt. of accelerating agent for hardening, pH controller, thickener, org. natural fiber, synthetic fiber, reinforcing agent, filler, or the like by a proper amt. are compounded with other antifungal fungistat. The component (B) is obtd. by processing an old electroless plating liquid containing sodium hypophosphite as a reducing agent to remove nickel and to desulfurize, then adding at least one of metal selected from calcium, magnesium, zinc and copper to the obtd. soln. essentially comprising sodium phosphite, and effecting the reaction to produce hardly-soluble metal phosphite. These components are mixed in a mixer, uniformly kneaded with addition of a proper amt. of water, molded with an extrusion molding machine, and hardened by drying.

Highly corrosion resistant reflector for traffic

Abstract: PURPOSE:To fulfill the function as a reflector for a long term, by depositing an alloy film mainly composed of nickel and phosphorus on the surface of the metallic mirror body by electroless plating. CONSTITUTION:An alloy film 12 chiefly composed of nickel and phosphorus is deposited on the metallic plate 11 such as a steel plate or a stainless steel plate by electroless plating to make a mirror body 1. In this case, one of the fabrication of the alloy plate 11 and the plating work may be done before the other. And a backing plate is fitted to the rearface of the mirror body 1. The alloy film 12 precipitates a nickel metal containing phosphorus by the reducing agent such as sodium hypophosphite from nickel ion by the electroless nickel plating. In this way, the reflectance of the mirror face is secured well and the corrosion resistance can be increased.

Method for directly forming electroplated layer on nonconductive material surface

Abstract: PURPOSE:To enhance the productivity by bringing the insulated part into conduction only by a Cu electroplating process without necessitating an electroless Cu plating process, simplifying the treating process, shortening the treating time, and improving the working environment. CONSTITUTION:A nonconductive material is treated with a liquid containing a silane coupling agent. The nonconductive material from this process is treated with a liquid containing an anion surfactant. The nonconductive material form this process is further treated with a liquid containing at least one kind among nitrogen-containing sulfur compounds consisting of thiourea and its derivatives and a palladium compound. Then the nonconductive material from this process is reduced with a reducing liquid containing at least one kind among sodium borohydride, sodium hypophosphite, hydrazine, dimethylamine borane, hydroxyamine and glyoxylic acid. The electroplated layer is directly formed on the nonconductive material passed through these processes.

Plating member for electronic parts

Abstract: PURPOSE:To prevent the discoloration of a substrate plating and to keep the commercial value in the member with a part of the surface of an electroless nickel-phosphorus plating applied on a metallic member plated with gold by specifying the phosphorus content of a substrate plating soln. CONSTITUTION:The entire surface (except the nonmetallic part) of a metallic material 11 (a metallic eyelet in the case of a glass terminal) is coated with an electroless nickel-phosphorus plating 12 contg. 10-13% phosphorus. The phosphorus content is adjusted by the amt. of a reducing agent (ordinarily sodium hypophosphite) or by changing the pH. The plating 12 is then coated with a gold plating 13 to cover the entire surface (mentioned above) of the metallic material 11, and then the part necessary to wire bonding or wire anchoring is masked with a mask 14. The surplus gold plating 13 is then removed and the mask 14 is removed. The plating 12 is highly resistant to the chemicals in a soln. for releasing the gold plating 13 and the mask 14, and hence the discoloration of the plating 12 is prevented.

Method of preventing generation of tin-plated whisker

Abstract: PURPOSE:To almost perfectly prevent generation of whiskers with a simplified method by keeping concentration of thiourea in the plating solution within the particular range on the occasion of conducting tin plating on a film carrier having conductor pattern formed by copper or the like. CONSTITUTION:Concentration of thiourea in the plating solution is set to 100 to 140g/l on the occasion of conducting tin plating on a film carrier having conductor pattern formed by copper or the like. For example, thiourea of 100g/l is added to the non-electrolytic tin-plating solution not including thiourea (elements: tin boron-fluoride 25g/l, sodium hypophosphite 30g/l, phenol sulphonic acid 160g/l, sulfuric acid 8g/l, and a little amount of interfacial active agent). The tin-plating is conducted for 10 minutes on the film carrier having conductor pattern formed by copper within the plating solution vessel heated up to 60 deg.C using such a plating solution. Thereby, generation of irregular precipitation on the conductor pattern can be controlled and generation of whiskers can almost be prevented.

Simultaneous etchant regeneration and metal deposition by electrodialysis

Abstract: A solution of spent etchant eg. ferric chloride etchant for etching nickel or copper chloride for etching brass is electrolysed as the analyte in a cell divided by a semipermeable membrane so that simultaneously the etchant is regenerated and metal eg. iron-nickel alloy or zinc containing minimum Cu respectively is deposited directly on the cathode, using a cathode current density of under 3000 A/m . The catholyte preferably comprises a Gp 1A halide eg. NaCl, a catalyst for reduction of metal cations eg. boric acid and a reducing agent for the deposition of the cations eg. sodium hypophosphite and has an independently adjusted pH eg. of 1 - 5.

Non-stimulating anti-tartar/plaque oral composition

Abstract: PURPOSE: To provide the oral compsn. which has both of improved anti-calculus and anti-plaque effects but does not stimulate the mucous membrane of the mouth. CONSTITUTION: This compns. contains the polymer of formula I [A is a random polymer residue contg. at least one unit of formula II and at least one unit of formula III ((m), (n) are integers sufficient for providing polymers having a weight average mol.wt. in a range of 400 to 5000; R1 to R4 are H, methyl, ethyl); B is H, residue A; R is OX; X is H, an alkali metal, an alkaline earth metal, a transition metal, ammonium, an alkylamine, an alkanolammonium] and (B) an antimicrobial agent selected from diphenyl ether, bis-guanide, a halogenated carbanilide and salicylamide. The unit of the formula II is formed of (meth)acrylic acid, an α-substd. acrylic acid, a β-carboxylalkylacrylic acid and the unit of the formula III is formed of maleic acid, fumaric acid, mesaconic acid, citraconic acid and is particularly preferably the polymer formed of the combination of acrylic acid, maleic anhydride and sodium hypophosphite.