Chemical composition for removing nickel-platinum alloy residues from a substrate, and method for removing such residues

Abstract

The present invention relates to an aqueous chemical composition C for removing from a substrate selectively under heat residues of a nickel-platinum alloy containing at least 8% by weight of Pt compared to the total weight of nickel-platinum alloy, characterised in that it is prepared by mixing a composition B comprising bromide ions and a composition H comprising hydrogen peroxide such that in the composition C, at the moment of mixing, the molar concentration of bromide ions is comprised between 0.15 mol/L and 0.45 mol/L and the molar ratio of hydrogen peroxide with respect to bromide ions is comprised between 1.1 and 2. The invention also pertains to a method for selectively removing nickel-platinum alloy residues containing at least 8% by weight of Pt compared to the total weight of nickel-platinum alloy from a substrate, comprising the following steps: preparing under heat a chemical composition C according to any one of claims 1 to 3, placing the hot chemical composition C and the substrate in contact for a sufficient duration to remove the nickel-platinum alloy residues from the substrate.

Dependencies are inferred from the claim text.