Patent ID: 8348134

Claim:
A composite silver nanoparticle comprising a silver core made up of aggregated silver atoms whose average particle diameter ranges from 1 to 20 nm and for which a lattice image is observed when said composite silver nanoparticle is observed by a high resolution transmission electron microscope, and an organic coating layer formed around said silver core which is composed of an alkoxide group and/or a carboxylic group obtained from an alcohol with a carbon number of 1 to 12 forming an silver alkoxide and an silver carboxylic acid on said silver core, respectively, wherein said composite silver nanoparticle is produced by the steps of arranging an alcohol solvent selected from alcohols with said carbon number of 1 to 12 composed of methanol, ethanol, propanol, buthanol, pentanol, hexanol, heptanol, octhanol, nonanol, decanol, undecanol and dodecanol, preparing an alcohol solution by mixing of micronized carbonic acid silver microparticle to said alcohol solvent, heating said alcohol solution in a reaction container with a generation temperature PT generating an aldehyde within 60 minutes, and forming said silver core with said average particle diameter ranging from 1 to 20 nm by reducing of said carbonic acid silver microparticle through said alcohol and/or said aldehyde generated.