One object of the present invention is to provide copper fine particles which have sufficient dispersibility when made into a paste and can be sintered at 150° C. or lower, the present invention provides copper fine particles, wherein the copper fine particles have a coating film containing copper carbonate and cuprous oxide on at least a part of the surface thereof, and a ratio between the following Db and the following Dv (Db/Dv) is in a range of 0.50˜0.90, Dv: an average value (nm) of the area equivalent circle diameter of the copper fine particles obtained by acquiring SEM images for 500 or more copper fine particles using a scanning electron microscope, and calculating by image analysis software, Db: a particle size (nm) of the copper fine particles obtained by measuring a specific surface area (SSA (m.sup.2/g)) of the copper fine particles using a specific surface area meter, and calculating by the following formula (1), Db=6/(SSA×ρ)×10.sup.9 . . . (1) in the formula (1), ρ is a density of copper (g/m.sup.3).

A method for producing fine copper particles includes producing fine copper particles having a coating film containing cuprous oxide on a surface by heating copper or a copper compound in a reducing flame formed by a burner. The fine copper particles are produced by adjusting a mixing ratio between a combustible gas and a combustion supporting gas which form the reducing flame such that a volume ratio of CO/CO.sub.2 is in a range of 1.5 to 2.4.

Disclosed herein is a granulated powder comprising a metal, a crosslinking agent and a water-soluble thermoplastic binder. The thermoplastic binder accounts for 5.0 to 18 percent by volume of a total volume, the crosslinking agent accounts for 1.0 to 8.0 percent by volume of the total volume, and the metal accounts for a remainder. The thermoplastic binder is a water-soluble polyvinyl alcohol, a polyvinyl butyral, a polyvinyl pyrrolidone, a polyethylene glycol, a hydrolyzed polymaleic anhydride or any combination of the foregoing, the crosslinking agent is an epoxy resin, a polyester resin, a polyester polyol or any combination of the foregoing.

There is produced a fine silver particle dispersing solution which contains: fine silver particles (the content of silver in the fine silver particle dispersing solution being 30 to 95% by weight), which have an average primary particle diameter of greater than 100 nm and not greater than 300 nm and which are coated with an amine having a carbon number of 8 to 12, such as octylamine, serving as an organic protective material; a polar solvent (5 to 70% by weight) having a boiling point of 150 to 300° C.; and an acrylic dispersing agent (5% by weight or less with respect to the fine silver particles), such as a dispersing agent of at least one of acrylic acid ester and methacrylic acid ester.

This disclosure relates to a fine silver particle dispersion including: (1) 65 to 95.4% by weight of fine silver particles which have an average primary particle diameter of 10 to 190 nm and which comprise 25% by number or less of silver particles having a primary particle diameter of 100 nm or larger, (2) 4.5 to 34.5% by weight of a solvent, and (3) 0.1 to 1.0% by weight of ethyl cellulose having a weight average molecular weight of 10,000 to 120,000.

The invention relates to a forming method of an alloy comprising predominantly Ti β or nearby β stage, comprising the steps of: Preparation of a homogeneous mixture of particle powder comprising micrometric particles of pure Ti and nanoscale particles of at least one additional element or compound promoting the beta phase of the Ti during its cooling from its phase transition temperature. exposing said particle powder mixture to a focused energy source that is selectively heat at least a portion of a bed of said homogeneous powder mixture at a temperature between 850 and 1850° C. cooling of the part having undergone this exposure with conservation of the phase b of the Ti.

The present disclosure is directed to methods of preparing substantially spherical metallic alloyed particles, having micron and sub-micron (i.e., nanometer)-scaled dimensions, and the powders so prepared, as well as articles derived from these powders. In particular embodiments, these metallic alloyed particles, comprising rare earth metals, can be prepared in sizes as small 80 nm in diameter with size variances as low as 2-5%.

To provide a fine nickel powder for an internal electrode paste of an electronic component, the nickel powder obtained by a wet method and having high crystallinity, excellent sintering characteristics, and heat-shrinking characteristics. The nickel powder is obtained by precipitating nickel by a reduction reaction in a reaction solution including at least water-soluble nickel salt, salt of metal nobler than nickel, hydrazine as a reducing agent, and alkali metal hydroxide as a pH adjusting agent and water; the reaction solution is prepared by mixing a nickel salt solution including the water-soluble nickel salt and the salt of metal nobler than nickel with a mixed reducing agent solution including hydrazine and alkali metal hydroxide; and the hydrazine is additionally added to the reaction solution after a reduction reaction initiates in the reaction solution.

A three-dimensional printing kit can include a binder fluid and a particulate build material. The particulate build material can include metal particles in an amount from about 95 wt % to about 99.995 wt % and carbon black particles in an amount from about 0.005 wt % to about 2 wt %, wherein weight percentages are based on a total weight of the particulate build material.

A double frame nanoparticle synthesis method includes: forming a first platinum layer of a closed loop structure on an edge region of a 2-dimensional gold nanoparticle; removing a portion of the gold nanoparticle in an exposed inner region thereof free of the first platinum layer, thereby forming a single frame structure; growing a first gold thin film on the single frame structure; forming a second platinum layer on inner and outer edge regions of the first gold thin film; removing a portion of the first gold thin film in an exposed region thereof free of the second platinum layer, thereby forming a double frame structure having an inner frame of a closed loop structure, and an outer frame having a closed loop structure surrounding the inner frame and partially connected to the inner frame; and forming a second gold thin film on a surface of the double frame structure.