Showing papers on "Sodium hypophosphite published in 1976"

Plating process and bath

Abstract: An electroless nickel bath for applying a nickel coating to articles without heat distortion, especially plastic articles, comprising water, nickel ions, a reducing agent for reducing the nickel ions to a metal, and a stabilizing agent for controlling the operating speed of the reducing agent, the bath being maintained at an alkaline pH, with the weight of the nickel ions being less than the weight of the hypophosphite anions. The nickel ions may be obtained from nickel salts, the reducing agent may be sodium hypophosphite, and the stabilizing agent may be sodium citrate and ammonium chloride. A replenish mixture for maintaining the bath comprising nickel ions and reducing agent anions in about the same ratio as in the original bath, and a stabilizing agent in about one-third the amount as in the original bath. A method of applying a nickel coating to articles comprising immersing the articles in said electroless nickel bath at room temperature.

Method for metallizing thermosetting plastics

Abstract: A method for metallizing a thermosetting resin is provided comprising: A. etching the surface of said resin with an oxidizing acid; B. activating the surface of said resin with a stannous chloride solution; C. sensitizing said resin in an aqueous solution of from 0.1 to 0.5 g per liter of palladium chloride and 1 to 6 ml of concentrated hydrochloric acid per liter; D. immersing said resin at about 90° C in an accelerator bath having a pH of about 7, said bath containing sodium hypophosphite, trisodium citrate, ammonium chloride and 2,4-dihydroxy benzoic acid; E. electrolessly nickel-plating said resin at a temperature of between about 96° to 99° C in a fast-depositing nickel bath having a pH of about 6.5 to 6.9 to form a nickel layer; F. electroplating said nickel layer with copper; and G. metallizing said copper layer to form a metallized layer. The deposited metal coatings are particularly strongly adhering, abrasion and wear-proof and particularly well suited for metallizing type carriers for teleprinters.

Synthesis of an ion exchanger containing α-aminometnylphosphinic acid groups☆

Abstract: Ion exchangers containing α-aminomethylphosphinic acid groups were synthesized by the Kobacknik-Filds reaction using sodium hypophosphite as the phosphorylation agent. The polyampholytes were found by IR spectroscopy and elemental analysis to contain -NHCH 2 P(O) (OH)CH 2 OH groups. The kinetics of the phosphorylation have been investigated.