2 results about "Metal colloids" patented technology

The present invention relates to a metal powder containing a metal of Au, Ag, Cu, or an alloy thereof, having an average particle size of 0.1 μm or more and 0.4 μm or less, and purity of 99.9% by mass or more. In this metal powder, a presence ratio, in terms of the number of particles, of non-spherical particles in the metal powder having a ratio (b / a) of a minor axis “a” and a major axis “b” of 3 or more is 1% or less. As a method for producing such a metal powder, in a wet reduction method including a metal colloid synthesis step and a metal powder granulation step of granulating metal colloidal particles into a metal powder, surfactants having alkyl groups having carbon numbers falling within specified ranges are preferably used as first and second dispersants in the metal colloid synthesis step and the metal powder granulation step.

The present invention relates to a method for preparing a metal (copper, molybdenum, zinc, magnesium, silver) colloidal solution using resonant vibration particle separation and cryogenic freezing technology, which is suitable for multiple fields such as engineering, biology and medicine. The present invention proposes a method for preparing a colloidal solution of any one of copper, molybdenum, zinc, magnesium or silver. According to the present invention, the cleaned metal blank is placed in distilled water or deionized water, and a resonant acoustic treatment is performed using an ultrasonic generator, thereby forming metal nanoparticles. Subsequently, the particles are subjected to cryogenic freezing treatment, followed by controlled cryogenic thawing, to obtain a stable metal colloidal solution with a particle size of 1-10 nm. The proposed method can generate nanoparticles of 5 to 50 nanometers in the resonant fragmentation stage, and can be further reduced to 1-10 nanometers during the cryogenic freezing process. This method can achieve a high-stability colloidal solution without the use of chemical stabilizers, avoid the production of toxic byproducts, and extend the storage period of the colloidal solution to 1 year.