Preparation method of nano-copper electrically conductive ink

The invention relates to a preparation method of nano-copper electrically conductive ink for ink-jet printing, which can be used for manufacturing printed circuit boards, and belongs to the technical field of nano-metal material and preparation processes of the ink for ink-jet printing. The preparation method is characterized in that a chemical reduction method is adopted; sodium hypophosphite is adopted as a reducing agent and copper salt is adopted as a precursor; LomarD and cetyltrimethyl ammonium bromide (CTAB) are added to serve as a surface active agent and a dispersing agent; the nano-copper electrically conductive ink which is not settled and agglomerated is prepared in a diethylene glycol (DEG) organic liquid-phase system under a condition that the temperature is controlled within a range of 120 DEG C to 160 DEG C; and according to the detection of particle size distribution, the particle size of nano-copper particles in the ink is 0 to 70nm. The preparation method has the advantages that the preparation method is applied to the fields of printed circuit boards, flexible printed circuit boards, radio-frequency identification/electronic tags, and the like; and through ink-jet printing on a substrate and, the nano particles can be mutually connected with each other only through low temperature sintering, so that excellent electrical conductivity can be obtained.