Showing papers on "Sodium hypophosphite published in 1995"

Effect of Coating Time on Corrosion Behavior of Electroless Nickel-Phosphorus Coated Powder Metallurgy Iron Specimens

Abstract: Powder metallurgy iron specimens with porosities in the range 0% to 2% were electroless coated with nickel-phosphorus alloy from baths containing sodium hypophosphite (NaH2PO2·H2O). The ef...

Multilayer printed wiring board, and its manufacture

Abstract: PROBLEM TO BE SOLVED: To prevent the cracks of an interlayer insulating film which occur at heat cycle, by constituting a conductor circuit of an electroless plated film and an electrolytic plated film, and providing a roughened layer at one part of the surface. SOLUTION: An inner-layer copper pattern 4, is made on a substrate consisting of glass epoxy resin, and an adhesive layer 2 is made on the inner- layer copper pattern 4. An opening for a via hole is made in the adhesive layer 2, and a catalyst nucleus is given to the surface, and then it is soaked in electroless copper plating bath so as to form an electroless plated copper film 12 all over the rough face. The electroless copper plated film 12 is etched to form a conductor circuit consisting of an electroless plated film 12 and an electrolytic copper plated film 13. The substrate of the conductor circuit is soaked in the electroless plating liquid of pH=9 consisting of copper sulfate, nickel sulfate, citric acid, sodium hypophosphite, boric acid, and an interface activator so as to form a roughened layer 11.

Carbodiimide catalysis in cross-linking of cotton cellulose with 1,2,3,4-butanetetracarboxylic acid

Abstract: This study examined carbodiimde catalysis (cyanamide, dicyandiamide, disodium cyanamide) in the cross-linking of cotton cellulose with 1,2,3,4-butanetetracarboxylic acid (BTCA). Considerable improvement in the smooth drying appearance of the treated cotton substantiated the fact that cellulose cross-linking has been achieved by BTCA in the presence of carbodiimide. Bath pH was a very important factor in determining the performance properties of the treated cotton. Two possible reaction mechanisms were proposed: direct esterification and anhydride intermediate formation. Both pathways involved the formation of urea. Semiquantitative analyses of the spectra obtained by Fourier transform infrared spectroscopy revealed that the cyanamide was somewhat less effective than were dicyandiamide and sodium hypophosphite in esterification efficiency. © 1995 John Wiley & Sons, Inc.

Synthetic technology of nitro-nitrogen yellow

Abstract: The process for synthesizing nitro-nitrogen yellow with H-acid as raw material includes such technological steps as hydrolysis of diazonium salt of H-acid with sodium hypophosphite to obtain RG salt, under existance of sodium hydroxide as alkaline reagent coupling said RG salt with 2,4-dinitroaniline diazonium salt to obtain crude product, dissolving in aqueous solution of sodium hydroxide, filtering, acid deposition with glacial acetic acid, heating in water bath, vacuum filtering and drying, and features high product purity and technical specification.

Production of benzotriazol based compound-containing water soluble preparation and its preparation

Abstract: PURPOSE: To obtain an anti-corrosive for copper based metal hardly crystallized even at a low or high temp., capable of preserving for a long time and jointly using with an anti-corrosive for iron based metal by adding a specific dissolution accelerating agent into a sparingly water-soluble triazol based compound. CONSTITUTION: The water soluble preparation is prepared by adding an addition polymer expressed by formula III or formula IV, formula V or the salt as the dissolution accelerating agent in the benzotriazol based compound expressed by formula I in the weight ratio of 2-50 to the bezotriazol based compound. In formula I, R 2 is a group expressed by formula II. The addition polymer to be added is acrylic acid, 2-acryloyl amino-2-methyl-propane sodium sulfonate or sodium hypophosphite addition polymer, the weight average molecular weight is preferably 1500-1800 and the molar ratio of sodium hypophosphite to the monomer is preferably 16:1. And an inorganic phosphate and the water soluble anti-corrosive for iron based metal, which is a compound easily releasing Zn ion in water, can be added to the anti-corrosive and used. COPYRIGHT: (C)1996,JPO

Electroless nickel plating bath using monoamine-type biodegradable chelating agent

Abstract: PURPOSE: To obtain a plating bath excellent in stability and capable of realizing an Ni plating having a high content of P at a high rate by incorporating a specified monoamine-type biodegradable chelating agent into an electroless Ni plating bath as an effective component. CONSTITUTION: At least one kind of the monoamine-type biodegradable chelating agent shown by the formula (where R is hydrogen or an unsubstituted or substituted hydrocarbonic group, R and R are hydrogen or an unsubstituted or substituted hydrocarbon group, R is hydrogen, -COOM-, -SO3 M or -PO3 M, and M is hydrogen, alkali metal or ammonium group) as a complexing agent is incorporated into an electroless Ni plating bath as the effective component. In this case, 0.2-30mols of the chelating agent is preferably used for 5-500mM of Ni ion, and the plating bath is preferably alkalized by NaOH, KOH or NH4 OH. Further, sodium hypophosphite is used as the reducing agent of the bath, and an Ni coating film having a high content of P is obtained at a high rate.

Electroless copper/ptfe composite coatings

Abstract: A composite Cu-PTFE coating was prepared by electroless copper plating with sodium hypophosphite as the reducing agent. The thickness of the composite was 5∼10μm. It consisted of 5 per cent PTFE an...

Synthesis of sodium mono(2,4,4'-trimethylpentyl)phosphinate. Optimization, purification, and surfactant properties

Abstract: Sodium mono(2,4,4'-trirnethylpentyl)phosphinate has been obtained as a main product with good yield from the reaction between diisobutylene and sodium hypophosphite. The procedure is defined by a set of operating conditions which enable obtaining the product with optimum yield. Empirical relationships between the product quality and the operative conditions have been found. The purity of the mono(2,4,4',trimethylpentyl)phosphinic acid was checked by 1R and 31P NMR spectroscopy and determined by potentiometric titration of an ethanol/water solution. Finally the critical micelle concentration of sodium mono(2,4,4'-trunethylpentyl)phosphinate and sodium mono(n-octyl)phospninate has been determined.

Electroless ni-based plating solution for aln substrate

Abstract: PURPOSE:To provide the plating solution with which a plated coating film having excellent properties such as film adhesion, hardness, can be formed selectively on only the wiring provided on the AlN substrate by specifying the Ni ion source, complexing agent, second complexing agent and reducing agent used as the components of the plating solution. CONSTITUTION:The composition of this plating solution consists of nickel sulfate (or that contg. water of crystallization), nickel chloride or nickel acetate as the Ni ion source, ethylene diamine as the complexing agent, lactic acid as the second complexing agent and sodium hypophosphite as the reducing agent. An appropriate combination of these components is prepared and an acid is added to the resulting composition to adjust its pH and the solution thus obtained is used as the objective plating solution. At the time of performing the plating, the temp. of the plating solution is preferably within the range of 60 to 80 deg.C and the concn. of the Ni ion source in the plating solution is preferably about 0.01 to 0.10 mol/l and also, the concn. of the complexing agent and the second complexing agent in the plating solution are preferably about 0.05 to 0. 20mol/l and about 0. 15 to 0. 30mol/l respectively and further, the concn. of the reducing agent in the plating solution is preferably about 0. 05 to 0. 30mol/l.

Manufacture of air electrode

Abstract: PURPOSE:To provide a high catalytic function with a small amount of a metal by forming an air electrode carrying the metal deposited from a solution containing the metal ion by a reducing agent into a sheet-like electrode. CONSTITUTION:Manganese oxide, activated carbon, conductive carbon, polytetrafluoroethylene(PTFE) in 47:35:12:7 weight ratio are mixed and kneaded and the resulting mixture is formed into a sheet with 0.6mm thickness to give an air electrode 5. The sheet is immersed in an aqueous solution containing 20g/l of silver cyanide, 100g/l of sodium hypophosphite as a reducing agent, and 80g/l of potassium cyanide under 70cmHg pressure for 10 minutes. Further, the obtained sheet is heated at 90 deg.C for 10 minutes to deposite silver. The resulting sheet-like electrode is press-stuck to a cylindrical stainless steel mesh coated with nickel and further together with the sheet-like electrode, a sheet with 0.23mm thickness and prepared by kneading carbon black and PTFE in 3:2 weight ratio and forming the mixture into a sheet is rolled double to give a cylindrical electrode and thus a battery is prepared.

Electrolytic Regeneration of Contaminated Electroless Nickel Plating Baths

Abstract: : Electroless nickel (EN) plating is used to apply a protective coating to a substrate without the use of an electric current. Following a catalytic activation step, a nickel phosphorous alloy (NiP) is deposited through chemical reactions on the surface of the part. The advantages over other metal coatings include: (1) coating uniformity, (2) corrosion resistance, (3) wear resistance, (4) desirable magnetic and electrical properties, and (5) indifference to part shape. The most common nickel source is nickel sulfate. Nickel ions are reduced to nickel metal by accepting electrons from an electron donor, typically hypophosphite, present in solution as sodium hypophosphite. Some of the hypophosphite is reduced to phosphorous, and is co-deposited with nickel to form a NiP alloy. As the nickel is plated onto the part, the concentrations of nickel and hypophosphite in the bath decrease. Nickel sulfate and sodium hypophosphite are periodically added to replenish these losses. When 100 percent of the original nickel has been replaced, this is termed a metal turnover (MTO).