Showing papers on "Sodium hypophosphite published in 1983"

無電解Ni-Cu-P合金めっき皮膜の電気抵抗特性

Abstract: The electric resistance behavior and the structure of electroless nickel-copper-phosphorus alloy films obtained from various kinds of plating baths containing sodium hypophosphite as a reducing agent were investigated by means of an X-ray diffraction method, a film resistance measurement, and a differential scanning carolimetry. It was found that resistivity of films as-plated became constant value more than 1-2μm thickness, and it became smaller when the contained the larger content of copper. For change of resistivity of films by the heat treatment, the ratio of its decrease became larger when the films contained the larger content of phosphorus and its relation corresponded well to the structural variation of films. For the films deposited from caustic alkaline citrate bath, the returning of films became worse, when content of copper incresed. The heat treatment at 300°C 1hr. in vacuum, however, developed its returning. In case of ammonia alkaline citrate bath, the returning of films were better than that deposited from caustic alkaline citrate bath. In all films asplated, the resulting temperature coefficient of resistance (TCR) were lower with decreasing the grain size of film and TCR were larger by the heat treatment.

Chemical plating solution

Abstract: PURPOSE:To obtain a chemical plating soln. having a long life when used at an almost neutral pH value by adding glycine to a plating soln. contg. a soluble nickel or cobalt salt, a hypophosphite, and a pH buffer as principal components. CONSTITUTION:About 5-200g/l, preferably about 10-100g/l glycine is added to a plating soln. contg. a nickel or cobalt salt, a hypophosphite acting as a reducing agent such as sodium hypophosphite, and a pH buffer. A nickel or cobalt salt of an inorg. acid soluble in the plating soln. such as sulfate, hydrochloride or nitrate is used as said nickel or cobalt salt, and >=1 kind of compound selected from org. acids such as acetic acid, citric acid and succinic acid and salts thereof is used as said pH buffer. Glycine shows an especially superior effect when it is used in combination with a citrate, preferably sodium citrate as the pH buffer.

Electroless plating of glass and ceramic

Abstract: PURPOSE:To apply a metallic coating film to the surface of glass or ceramic, with high adhesivity, by sensitizing the surface of the glass, etc. in an aqueous solution containing Sn ion and F ion, activating the surface, and carrying out the electroless plating. CONSTITUTION:The surface of glass or ceramic is ordinarily etched, and sensitized in an aqueous solution containing 0.76-37.9g of Sn ion and 0.24-12.1g of F ion per liter. The sensitized surface of the article to be treated is activated e.g. with an aqueous solution containing Pd or colloidal Pd and then immersed in an electroless plating bath containing e.g. 0.1mol of nickel sulfate, 0.2mol of sodium hypophosphite, and 0.1mol of sodium citrate to form an electrode film composed of Ni to the surface of the glass, etc. A fine metallic coating film having high adhesivity can be formed on the surface of glass or ceramic by this process without being affected with undesirable effects such as diffusion.

Nitrogen and phosphorus-containing polyampholytes based on polyvinylbenzylamine☆

Abstract: Ionites with α-aminomethyl phosphinic acid groups have been prepared by chemical modification of polyvinylbenzylamine of various structures with sodium hypophosphite in the presence of formaldehyde, according to the Kabachnik-Fields reaction. The optimum conditions for polyampholyte synthesis were found. Their composition and structure were established and the basic physico-chemical properties studied. The nature of the chemical bond of the ionogenic groups of the polymer with certain metallic ions was studied. The study of the sorption properties of the synthesized polyvinylbenzylamine derivatives and calculation of the stability constants of the complexes with certain metals showed a high affinity for the latter. The nitrogen and phosphorus-containing sorbents can be used for selective extraction of the ions of certain metals.