Method of making a colloidal palladium and/or platinum metal dispersion
AssigneeMinnesota Mining and Manufacturing Company
InventorsRobin E. Wright, Hsin H. Chou
Life of this patent
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Abstract
A method of making a colloidal metal dispersion that is useful as a toner fluid. The method involves reducing a palladium and/or platinum metal of a metallo-organic palladium and/or platinum metal salt in a dispersing medium that contains a soluble surfactant and a carrier liquid. The palladium and/or platinum metal of the metallo-organic metal salt is reduced in the dispersing medium to form elemental metal particles. The soluble surfactant is present in the dispersing medium in an amount sufficient to charge and stabilize the elemental metal particles as a colloidal metal dispersion.
Claims27
A method of making a colloidal palladium and/or platinum metal dispersion that can be used as a toner fluid, which method comprises:
- reducing a palladium and/or platinum metal of a metallo-organic palladium and/or platinum metal salt which lacks halide functionally in a dispersing medium comprising an organic carrier liquid and a soluble surfactant, the palladium and/or platinum metal of the metallo-organic metal salt being reduced in the dispersing medium to form colloidal elemental palladium and/or platinum metal particles, the soluble surfactant being present in the dispersing medium in an amount sufficient to charge and stabilize the elemental palladium and/or platinum metal particles as a colloidal metal dispersion.
A method of making a metallic toner fluid composition, which method comprises:
- introducing a metallo-organic palladium or platinum metal salt which lacks halide functionally or combination thereof into an organic carrier liquid that contains a soluble surfactant and has a dielectric constant less than 3.5 and a volume resistivity greater than 10.sup.12 ohm-cm;
- and
- reducing the palladium or platinum metal or combination thereof to form metal particles of elemental palladium, elemental platinum, or elemental combinations thereof having sizes in the range of 1 to 250 nm, the metallo-organic palladium and/or platinum metal salt being reduced to form the palladium and/or platinum elemental metal particles by heating the carrier liquid, and optionally introducing a secondary reducing agent into the carrier liquid, the metal particles of palladium, platinum, or combinations thereof being suspended as colloidal particles in the organic carrier liquid by a soluble surfactant that is present in the organic carrier liquid.
Dependencies are inferred from the claim text.