The present application provides a 3D printing method. The present application can provide as a method for efficiently performing 3D printing, for example, a 3D printing method capable of more rapidly and efficiently producing a three-dimensional shape precisely realized up to a fine portion.

This silver paste includes a silver powder and a solvent, in which the silver powder includes first silver particles having a particle size of 100 nm or more and less than 500 nm, second silver particles having a particle size of 50 nm or more and less than 100 nm, and third silver particles having a particle size of 1000 nm or more and less than 10000 nm, and the content of the first silver particles is 12% by volume or more and 90% by volume or less, the content of the second silver particles is 1% by volume or more and 38% by volume or less, and the content of the third silver particles is 5% by volume or more and 80% by volume or less, regarding a total amount of the silver powder as 100% by volume.

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.

There are provided a spherical silver powder which has the same diameter as that of a spherical silver powder produced by a conventional wet reduction method and which can sufficiently sinter the silver particles thereof to cause the silver particles to be adhered to each other at a relatively low temperature to form a conductive film having a low volume resistivity when it is used for a baked type conductive paste, and a method for producing the same. A spherical silver powder, which contains a neutral or basic amino acid having a carbon number of not less than 5 in each of particles thereof and which has an average particle diameter D.sub.50 of 0.2 to 5 μm based on a laser diffraction method, is produced by adding the neutral or basic amino acid having the carbon number of not less than 5 (such as proline, tyrosine, tryptophan, phenylalanine, arginine or histidine) to a water reaction system containing silver ions to mix a reducing agent therewith to deposit silver particles by reduction.

A caster assembly configured to process and store a material includes a reaction chamber, a storage assembly configured to store material processed in the reaction chamber, and a blower configured to process and store the material. The reaction chamber includes a vessel configured to hold the material in a melted state prior to processing and a powder generating assembly configured to receive the material from the melting vessel. The powder generating assembly includes a feeding chamber and a feeding device disposed at least partially within the feeding chamber. The feeding device includes at least one nozzle configured to inject inert fluid, where the fluid is a gas, liquid, or combination of the two into the feeding chamber and a material inlet through which the material is configured to flow into the feeding chamber to be exposed to the inert fluid, where the fluid is a gas, liquid, or combination of the two.

Provided are gold-coated flat silver particles, a dispersion including the gold-coated flat silver particles and a dispersion medium, a method of the dispersion, a coating film including the gold-coated flat silver particles, and an antireflection optical member. The gold-coated flat silver particles include flat silver particles and a gold coating layer, in which an average thickness of the gold coating layer on principal planes of the particles is 0.1 nm to 2 nm, and a ratio of the average thickness of the gold coating layer on the principal planes of the particles to an average thickness of the gold coating layer on edge surfaces of the particles is 0.02 or higher.

A tungsten-carbide-based hard material includes the following components: tungsten carbide with an average particle size of 0.1-1.3 μm; 1.0-5.0 wt. % (Co+Ni), with a ratio of Co/(Co+Ni) in wt. % of 0.4≤Co/(Co+Ni)≤0.95; 0.1-1.0 wt. % Cr, with a ratio of Cr to (Co+Ni) in wt. % of 0.05 Cr/(Co+Ni) 0.20; 0.01-0.3 wt. % Mo; and 0.02-0.45 wt. % Me, where Me represents one or more elements from the group Ta, Nb, Hf and Ti, preferably Ta and/or Nb; and wherein 0.01≤Me/(Co+Ni)≤0.13.

A copper paste for joining contains metal particles and a dispersion medium, in which the copper paste for joining contains copper particles as the metal particles, and the copper paste for joining contains dihydroterpineol as the dispersion medium. A method for manufacturing a joined body is a method for manufacturing a joined body which includes a first member, a second member, and a joining portion that joins the first member and the second member, the method including: a first step of printing the above-described copper paste for joining to at least one joining surface of the first member and the second member to prepare a laminate having a laminate structure in which the first member, the copper paste for joining, and the second member are laminated in this order; and a second step of sintering the copper paste for joining of the laminate.

Fluorescent bimetallic nanocomposites (M.sub.1@M.sub.2-NCs) of silver-gold (Ag@Au-NC) and silver-platinum (Ag@Pt-NC) are prepared by reducing silver nitrate (AgNO.sub.3) on gold nanoparticles (AuNPs) and platinum nanoparticles (PtNPs) using sodium borohydride (NaBH.sub.4) at alkaline pH=11, in the presence of a lysozyme that acts as a template, and in the presence of a capping and stabilizing agent. The biocompatible bimetallic nanocomposites (M.sub.1@M.sub.2-NCs) have promising multifunctional applications (cell imaging, bio-sensing, therapeutics) observed by both in vitro as well as in vivo experiments. The fluorescent bimetallic nanocomposites (M.sub.1@M.sub.2-NCs) of silver-gold (Ag@Au-NC) and silver-platinum (Ag@Pt-NC) may be useful as an alternative nanomedicine in cancer theranostics applications.

Fluorescent bimetallic nanocomposites (M.sub.1@M.sub.2-NCs) of silver-gold (Ag@Au-NC) and silver-platinum (Ag@Pt-NC) are prepared by reducing silver nitrate (AgNO.sub.3) on gold nanoparticles (AuNPs) and platinum nanoparticles (PtNPs) using sodium borohydride (NaBH.sub.4) at alkaline pH=11, in the presence of a lysozyme that acts as a template, and in the presence of a capping and stabilizing agent. The biocompatible bimetallic nanocomposites (M.sub.1@M.sub.2-NCs) have promising multifunctional applications (cell imaging, bio-sensing, therapeutics) observed by both in vitro as well as in vivo experiments. The fluorescent bimetallic nanocomposites (M.sub.1@M.sub.2-NCs) of silver-gold (Ag@Au-NC) and silver-platinum (Ag@Pt-NC) may be useful as an alternative nanomedicine in cancer theranostics applications.