Showing papers on "Sodium hypophosphite published in 1989"

Electrodeposition of amorphous ternary nickel-chromium-phosphorus alloy

Abstract: Amorphous ternary nickel-chromium-phosphorus alloys are electrodeposited from a bath comprising a nickel salt, a chromium salt, a phosphorus source such as sodium hypophosphite, a complexing agent for the nickel ions, supporting salts to increase conductivity, and a buffering agent. The process is carried out at about room temperature and requires a current density between about 20 to 40 A/dm 2 .

Structure of amorphous Fe-Cr-P alloys prepared by electrodeposition

Abstract: Iron-chromium-phosphorus (Fe–Cr–P) alloys were prepared by electrodeposition from an acidic citrate electrolyte using sodium hypophosphite as the source of phosphorus. These alloys form a passive oxide layer when exposed to air and are useful as protective coatings on steel. The current efficiency of the plating process reaches a maximum of 20% at a current density of 100 mA/cm2 where the alloy has 10% Cr and 19% P. X-ray diffraction patterns and TEM analysis show that the alloy is amorphous. TEM results also indicate that small oxide particles (5–20 nm) are dispersed in the amorphous structure. Besides Fe, Cr, and P, the alloys contain a low level of oxygen (4–7%) in the form of mixed iron and chromium oxides, as confirmed by AES analysis. When heated, the amorphous structure transforms into a mixture of Fe3P and Cr3P, along with α–Fe–Cr grains. This phase transformation occurs in the temperature range of 450–460 °C for alloys with 19% P.

Production of high-surface area metal-deposited catalyst

Abstract: PURPOSE: To obtain the high-surface area metal-deposited catalyst which is deposited with a catalyst metal to a uniform grain size with a high degree of dispersion on a carrier and deposited with the simple substance of the metal having the high resistance to sintering is obtd. by using a reducing agent having the weak reducing power as a reducing agent and contg. phosphorus atoms at the time of depositing the catalyst metal on the abovementioned carrier. CONSTITUTION: The soln. of metal-contg. ions consisting of platinum and/or palladium is reduced by using 1 or ≥2 reducing agents selected from a group consisting of sodium hypophosphite, potassium hypophosphite, and ammonium hypophosphite to reduce the abovementioned metal-contg. ions to the metal. The abovementioned metal is deposited on the carrier consisting of carbon or inorg. oxide. The high-surface area metal-deposited catalyst which is deposited with the catalyst metal to the uniform grain size with the high degree of dispersion on the carrier and deposited with the simple substance of the metal having the high resistance to the sintering is obtd. by this method. COPYRIGHT: (C)1990,JPO&Japio

Gold plating bath and method

Abstract: A gold plating bath having potassium aurous cyanide and thiourea complexing agent dissolved in water and adjusted to an acidity of pH 3 or lower can be used as either electro-­plating or electroless plating bath. Bright gold electro-­plating is possible when a brightener is added to the bath. Electroless plating is possible when a reducing agent, typically sodium hypophosphite is added to the bath.

Electroless Plating through Successive Pretreatment with Aminosilane and PdCl2

Abstract: Electroless nickel deposition on glass beads was carried out by a new plating method without using stannous chloride, which needs a successive pretreatment with aminosilane and PdCl2 It was presumed that metallic palladium nuclei was formed in the initial stage and initiated the plating

Preparation of low molecular weight water-soluble acrylic polymer

Abstract: PURPOSE: To obtain conveniently the title polymer without coloring and odor by preparing an acrylic polymer by a redox polymn. using a combination of each specified oxidizing agent and reducing agent. CONSTITUTION: An acrylic polymer (e.g. polyacrylic acid) is prepd. by a redox polymn. using a combination of an oxidizing agent comprising a persulfate (e.g. ammonium persulfate) and H 2 O 2 at a molar ratio of 10/1-1/2 and a reducing agent (e.g. sodium hypophosphite) at a molar ratio of 2/1-1/20. COPYRIGHT: (C)1991,JPO&Japio

Wire for wire saw

Abstract: PURPOSE:To enable the cutting of a hard and brittle material such as a semiconductor, etc, at a high speed by providing an electroless plating layer on the surface of a metal wire such as a music wire or a tungsten wire, etc, and making the electroless plating layer dispersedly contain abrasive grains CONSTITUTION:After giving degreasing and pickling treatments on the surface of a music wire of, eg, 02mm in diameter, an Ni-P electroless plating layer 2 is formed by means of a pH6 bath containing approx 30g/l nickel sulfate, approx 10g/l sodium hypophosphite, approx 10g/l sodium acetate, and approx 20g/l SiC grains with grain diameters of 3-20mum This plating layer 2 is formed at a thickness of approx 5-15mum with a content of SiC abrasive grains 3 of about 29% Thereby, a uniform plating layer with a high content of abrasive grains can be formed on the surface of a metal wire to enable the cutting of a hard and brittle material such as a semiconductor or ceramics, etc, at a high speed

Manufacture of voltage-dependent nonlinear resistance element

Abstract: PURPOSE:To obtain a nonlinear resistance element having an excellent characteristic by a method wherein a paste composed mainly of Cu is fired, an ohmic electrode is formed on a sintered substance composed mainly of SrTiO3, a plated part composed mainly of Ni is formed on it additionally and an electrode composed mainly of a solder is piled up on it CONSTITUTION:A paste whose main component is Cu and which contains a borosilicate lead-based glass frit and a resin is applied, by using a screen printing method, to a region used to form an electrode of a sintered substance 1 composed mainly of SrTiO3 After that, it is dried and fired in the air, and an ohmic electrode 2 is formed Then, a surface-active agent 3 composed of palladium and silver is applied to it by using the screen printing method, after which, this assembly is immersed in a plating solution composed of nickel chloride, sodium hypophosphite or the like, an electroless plated part 4 of nickel and phosphorus is formed and this assembly is washed in running water and dried In addition, an electrode 5 composed mainly of a solder is formed on it by an electrolytic plating operation, this assembly is washed in running water and dried By this setup, corrosion resistance is excellent, a change with the passage of time is small and a connection to an external electrode can be made easily

Electroless Plating of Pd-P Alloys from Ethylenediamine Complex Solutions

Abstract: Electroless plating of Pd-P alloys from palladium-ethylenediamine complex solutions containing sodium hypophosphite as a reducing agent, was investigated. The deposition rate of Pd-P alloys was markedly influenced by the concentration of palladium chloride and bath temperature. The phosphorus content of deposits was proportional to the 0.2 power of sodium hypophosphite concentration. In Pd-P alloys, the amorphous solid was converted with heat treatment at 250-300°C into either stable crystal phase Pd plus Pd8P or Pd plus Pd6P, according to phosphorus content. It was found that hardness increased when heat treatment of the alloy resulted in the formation of PdxP crystals.

Method for polymerizing diallylamine and derivative thereof

Abstract: PURPOSE: To obtain a low-molecular weight polymer without affecting polymerization rate, etc., by polymerizing a specific monomer using a hypophosphorous acid (salt) as a polymerization degree regulator. CONSTITUTION: The objective polymer obtained by polymerizing a monomer (e.g. diallydimethylammonium chloride) expressed by the formula (R 1 and R 2 are H, 1-5C alkyl, benzyl or cyclohexyl; X - is F - , Cl - , Br - , I - , NO, HSO or H 2 PO) using hypophosphorous acid and/or salt thereof (e.g. sodium hypophosphite) as a polymerization degree regulator. COPYRIGHT: (C)1991,JPO&Japio

Production of metal-coated inorganic powder

Abstract: PURPOSE:To produce the title powder with a simple process without using noble metals and strong acids by fixing the metal ion in inorg. powder having ion exchangeability by ion exchange, and applying reduction and electroless plating to the powder. CONSTITUTION:The inorg. powder having ion exchangeability such as montmorillonite, hectorite, and fluoromica is dipped in a metal ion soln. contg. >=one kind among Ni , Fe , Cu , etc., and ion exchange is carried out. By this process, the metal ion is most uniformly distributed and fixed at the ion exchanged point in the inorg powder or on the surface. The metal ion fixing inorg. powder is then heated, for example, in the reducing gas such as H2 and CO, and then dipped in an aq. soln. of the reducing agent such as sodium hypophosphite and boron hydride and reduced to deposit the metal particles on the surface of the inorg. powder. The inorg. powder deposited with the fine metal particles is treated with a metal ion-contg. electroless plating soln. to form a metal coating film on the surface of the inorg. powder.

Electroless nickel-phosphorus plating bath

Abstract: PURPOSE: To produce an electroless Ni-P plating bath having superior bath stability and depositing a plating film having superior nonmagnetic stability by preparing a plating bath contg. at least nickel sulfate, sodium hypophosphite and Mg ions. CONSTITUTION: An electroless Ni-P plating bath contg. at least nickel sulfate by about 10-500g per 1l water, sodium hypophosphite by 5-200g per 1l water and Mg ions by about 0.1-50g per 1l water is prepd. A brightener, a pH buffer, a complexing agent, a bath stabilizer, etc., may be properly added to the plating bath. A plating bath forming a plating film useful as the nonmagnetic base film of a magnetic disk is obtd. COPYRIGHT: (C)1991,JPO&Japio

Electroless Pd-Ni-P Alloy Plating and Properties of the Deposit

Abstract: In terms of corrosion resistance, wear resistance and contact resistance, electrodeposited Pd-Ni alloy was a substitute for gold. This report describes the electroless plating of Pd-Ni-P alloys from ethylenediamine complex solutions containing sodium hypophosphite as a reducing agent, and properties of the deposits. The nickel content of the deposits and thier hardness were found to be proportional to the concentration of nickel ion in the baths. The hardness of 63mol% nickel alloy deposit was 750Hv. The deposits showed maximum hardness after heat treatment at 350°C, reaching over 1000Hv for alloys containing 10mol% nickel or more. An increase in the nickel content of the deposits led to some deterioration in solderability, but no appreciable changes were found in contact resistance, even after humidity testing for six days.

Iron plating bath

Abstract: PURPOSE:To inhibit the formation of ferric ions and to increase the efficiency of iron plating by adding sodium hypophosphite to an acidic iron plating bath. CONSTITUTION:Sodium hypophosphite is added to an acidic iron plating bath for iron electroplating in about 3:1-5:1 molar ratio to iron. The pH of the plating bath is adjusted to about 2-3. The plating bath is suitable for use in the production of a magnetic recording medium. For example, Al (alloy) is anodically oxidized and iron is filled into the micropores in the resulting anodic oxide film by plating with an AC power source to produce a high density magnetic recording medium having superior corrosion resistance and durability.

テルル(iv)-ハロゲン化物イオン-1,10-フェナントロリン三元錯体の抽出挙動とテルル(iv)の原子吸光定量

Abstract: Tellurium(IV) can be easily extracted into nitrobenzene from acid solution containing halide ion and 1, 10-phenanthroline (Phen). It seems to be due to the formation of the ternary complex between Te( IV)-halide complex and protonated 1, 10-phenanthroline. The ternary complexes are quantitatively extractable when the acid concentration is more than 0. 5 M for the iodocomplex and 2 M for the bromocomplex. The procedure for the extraction was as follows. The sample solution containing Te(IV) was introduced into a 100 ml separatory funnel to which potassium iodide or hydrogen bromide were added and the acid concentration was adjusted with sulfuric acid. After 1, 10-phenanthroline solution was added, the volume was made up to 20 ml with water. The mixture was shaken with 4 ml of nitrobenzene. The amount of Te(IV) in the organic phase was measured by AAS. The calibration curves obtained by the above procedure were linear up to 4× 10-5 M for Te(IV) as the iodocomplex and 2 × 10-5 M as the bromocomplex, respectively. The detection limit was 5 × 10-7 M. The influence of coexisting metal ions on the determination of Te(IV) was investigated. By the addition of reducing agent such as sodium hypophosphite and the pre-extraction of metal ions at pH 3. 0 as ternary complex with phenanthroline in the form of [M (Phen) m-Xn], the interferences by many metal ions could be excluded. The composition of the extracted species was investigated by the equilibrium method and elementary analysis. The results showed it to be Te(IV) : halide ion : Phen = 1 : 6 : 2. It could be assumed that Phen would take part in the formation of ion-pairing as the cation (PhenH+).

Resin composition and production thereof

Abstract: PURPOSE:To provide a resin composition having a large impact strength and a less coloring, by compounding polyphenylene sulfide with hypophosphorous acid (salt). CONSTITUTION:A thermoplastic resin mainly comprising polyphenylene sulfide is compounded with 0.01-5wt.%, preferably 0.05-3wt.%, of hypophosphorous acid or a salt thereof (e.g. hypophosphorous acid or sodium hypophosphite).

Double oven heating nylon vessel

Abstract: PURPOSE: To eliminate a browning at the time of cooking food in a convection thermal energy oven by incorporating a specific amount of an additive selected from an ortho-phosphorous acid, hypophosphorous acid, their alkali metals and alkali earth metal salts in a polyamide. CONSTITUTION: A polyamide of an aliphatic polyamide container contains at lest 0.2 wt.% of an additive selected from an ortho-phosphorous acid, hypophosphorous acid, alkali metal and alkali earth metal salts of their acids. The adapted additive is a sodium hypophosphite. The container is formed of a polymer based on the polyamide and compatible olefin or a polymer based on the a partly crystalline polyamide and compatibilized olefin of an amount of 1 to 30 wt.% of the overall weight. The polyamide has 6-24 carbon atoms, and contains an aliphatic dicarboxylic acid, an aliphatic diamine or an aliphatic amino acid having 6 to 24 carbon atoms. Particularly, as the adapted polyamide, a nylon 66, a nylon 6 and their mixture or a nylon 6 having an intrinsic viscosity of a range of 0.75 to 1.3 mm /G is useful.

Production of sodium hypophosphite

Abstract: PURPOSE:To enable effective utilization of phosphin by feeding back element P obtd. by pyrolyzing by-produced phosphin by allowing it to contact with powdery P alloy, to a reaction system for the production of sodium hypophosphite. CONSTITUTION:A production reaction for sodium hypophosphite is carried out by charging liquid white phosphorus from a tank 1, NaOH soln. from a tank 2, and slurry of slaked lime from a tank 3, to reaction tank equipped with a stirrer 5 respectively. Generated sodium hypophosphite is recovered in the form of soln. in a tank 7. After dehydrating PH3 generated by said reaction in a dehydration tower 9, it is transferred to a decomposition tower 10 packed with powder of P alloy. A heater 11 is installed to the outside of the decomposition tower 10 which controls the temp. so as to cause effective decomposition of PH3. Elemental P generated in the decomposition tower 10 is recovered in a tank 13 and used circulatory by feeding back to the tank 1. If PH3 is needed as it is, it is recovered in the form of PH3.

Production of photomask

Abstract: PURPOSE:To eliminate the halation of a hard mask by immersing an Ni-P mask into a sodium hypophosphite, soln., then plating the same by an electroless plating liquid contg. hydrazine. CONSTITUTION:After an Ni-P film is formed on a transparent substrate by electroless plating, the film is patterned by photolithography. This substrate is then immersed into 0.1-1.0mol./l sodium hypophosphite soln. and is thereafter immersed into the electroless plating liquid (A) contg. the hydrazine as a reducing agent so that only the patterned parts are replated. NiSO4, sodium citrate, etc., may be incorporated in addition to the hydrazine into the plating liquid A. The black metallic film having good adhesion is then formed on the substrate and, therefore, the photomask free from halation is obtd.