Abstract: Copper particles are provided that each include a core particle made of copper and a coating layer that coats the surface of the core particle, wherein the coating layer is made of a copper salt of an aliphatic organic acid. It is also preferable that the copper particles have an infrared absorption peak in a range of 1504 to 1514 cm?1 and no infrared absorption peak in a range of 1584 to 1596 cm?1. It is also preferable that, in thermogravimetric analysis of the copper particles, the temperature at which the ratio of the mass loss value to the mass loss value at 500° C. reaches 10% is from 150° C. to 220° C. A method is also provided for producing copper particles, the method including bringing core particles made of copper into contact with a solution containing a copper salt of an aliphatic organic acid to thereby coat the surface of the core particles.

Abstract: Copper particles are provided mainly containing a copper element. In the copper particles, a ratio (S1/B) of a first crystallite size S1 to a particle size B is 0.23 or less, where the first crystallite size is obtained using Scherrer equation from a full width at half maximum of a peak derived from (111) plane of copper in X-ray diffraction measurement, and the particle size is calculated from a BET specific surface area. In the copper particles, a ratio (S1/S2) of the first crystallite size S1 to a second crystallite size S2 is 1.35 or less, where the second crystallite size is obtained using Scherrer equation from a full width at half maximum of a peak derived from (220) plane of copper in X-ray diffraction measurement. A method for manufacturing the copper particles is also provided.

Abstract: Copper particles are provided that each include a core particle made of copper and a coating layer that coats the surface of the core particle, wherein the coating layer is made of a copper salt of an aliphatic organic acid. It is also preferable that the copper particles have an infrared absorption peak in a range of 1504 to 1514 cm?1 and no infrared absorption peak in a range of 1584 to 1596 cm?1. It is also preferable that, in thermogravimetric analysis of the copper particles, the temperature at which the ratio of the mass loss value to the mass loss value at 500° C. reaches 10% is from 150° C. to 220° C. A method is also provided for producing copper particles, the method including bringing core particles made of copper into contact with a solution containing a copper salt of an aliphatic organic acid to thereby coat the surface of the core particles.