Preparation method of nano copper paste for conductive ink

The invention relates to a preparation method of nano copper paste for conductive ink. The preparation method of the nano copper paste for conductive ink includes adding copper source into solution, mixing evenly at room temperature, and obtaining copper source dispersing liquid; adding dispersant into the copper source dispersing liquid, mixing evenly at room temperature, and obtaining first mixture; adding complexing agent into the first mixture, mixing evenly at room temperature, and obtaining a second mixture; adding a reducing agent to the second mixture, reacting for 30 minutes to 3 hours at room temperature, and obtaining nano copper colloid; concentrating the nano copper colloid, and obtaining the nano copper paste used for conductive ink. The preparation method is simple, and nano copper is difficult to oxidize and has fine dispersing performance.