This work describes the synthesis of a conductive ink based on silver nanoparticles. In the reactions, the precursor AgNO3 was dissolved in water and precipitated as silver oxide by NaOH. Hydrazine was added as a reducing agent and depending on the reaction, poly(acrylic acid) or poly(methacrylic acid) as a stabilizer. After the synthesis, the ink formulation was performed by homogenization on the ultrasonic bath. Some addition of ethylene glycol to ink formulation enables uniform ink drying while buffer addition enables stable basic ink conditions. Homogenization of the mixture was monitored spectrophotometrically. With the obtained ink and with the aid of a printer, silver lines were printed on a flexible substrate and then sintered in two ways. The first sintering was carried out in periods of 20 minutes at temperatures ranging from 20 to 140 °C while the other sintering involved heating at 120 °C for periods from 30 to 180 minutes. Resistances of the sintered lines or electrodes were measured with two- and four- point measurements while the thickness of the conductive layer was determined using SEM microscopy. Based on the measured dimensions, electrical resistivity of electrodes with minimal values ranging from 1,78*10^-8 to 2,77*10^-8 Ωm were calculated. Obtained results are very close to the ideal macroscopic silver resistivity value of 1,68*10^-8 Ωm. The thickness of the printed layer was, apart from microscopic, determined electrochemically. It has been observed that during the increase of the temperature, or the extension of the sintering time, the resistance drops, and thus the resistivity of the printed electrodes.