| 摘要 |
PROBLEM TO BE SOLVED: To provide silver microparticles of average particle diameters 30-100 nm excellent not only in heat shrinkability and low-temperature sinterability but also infilling properties into an electrode and a circuit pattern formed on a substrate; a method for producing the silver microparticles; and a conductive paste containing the silver microparticles.SOLUTION: A method for producing silver microparticles includes: preparing an aqueous solution (solution A) using silver nitrate and a high-molecular-weight protecting agent; preparing another aqueous solution (solution B) different from the liquid A by dissolving a reductant and a low-molecular-weight protecting agent; and separating, washing, and drying the silver microparticles gained by dropping the liquid B into the liquid A for reduction precipitation. The silver microparticles are obtained not only by controlling the temperature of the mixed solution to 40°C or below when the liquid B is dropped into the liquid A but also by performing a drying step in vacuum freeze-drying; and thereby have 3.0 g/cmor higher tapped density although the average diameters of the fine particles are 30-100 nm, so that the filling properties in an electrode or a circuit pattern formed on the substrate are excellent. |
