COPPER PARTICLES AND MANUFACTURING METHOD THEREFOR

These copper particles each comprise: a core part containing copper; and a copper oxide layer formed on the surface of the core part and containing CuO and Cu2O. The condition of Y >= 36X - 18 is satisfied where X is the content ratio (mass %) of oxygen contained in a copper particle and Y is the crystallite size (nm) of Cu2O contained in the copper oxide layer. It is also preferable that the value of DC/D50, that is, the ratio of the crystallite size DC (um) of metallic copper contained in the core part to a volume cumulative particle size D50 (um) at a cumulative volume of 50 volume % as measured using a laser diffraction/scattering particle size distribution measurement method, is between 0.10 and 0.40 inclusive. In addition, it is also preferable that the oxygen content ratio is between 0.80 mass % and 1.80 mass % inclusive. 本发明的铜颗粒具有包含铜的芯部和形成于该芯部的表面的包含CuO和CuO的氧化铜层。当将铜颗粒中所包含的氧的含有比例(质量％)设定为X、将氧化铜层中所包含的CuO的微晶尺寸(nm)设定为Y时，满足Y≥36X-18的条件。芯部中所包含的金属铜的微晶尺寸D(μm)与基于激光衍射散射式粒度分布测定法的累积体积为50容量％时的体积累积粒径D(μm)的比例即D/D的值还优选为