Ultrafine metal pattern forming method, ultrafine metal patterns, and electronic components

Provided is a method for forming ultrafine metal patterns having excellent pattern cross-section shapes, by means of a technology that combines a printing process and a plating process. Further provided are: ultrafine metal patterns, which, by providing excellent adhesion to each interface of layered products including plated core patterns, are preferably used as high-precision electronic components; and an ultrafine metal pattern production method. Specifically provided is an ultrafine metal pattern forming method comprising: (1) a step for forming a receiving layer obtained by applying a resin composition, which contains a medium and a urethane resin or a vinyl resin with a weight average molecular weight of at least 5,000, on a substrate; (2) a step for printing ink containing plated core particles by letterpress reverse printing, and forming a plated core pattern on the receiving layer; and (3) a step for depositing metal, by non-electrolytic plating, on the plated core pattern that was formed. Further specifically provided are ultrafine metal patterns obtained by said method, and electronic components that include the ultrafine metal patterns.