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In the article, low cost, RFID antenna is fabricated by gravure printing with PET acting as the substrate. The nanosilver ink with 50% silver content is prepared in the lab and the printing speed is set to 5m/min. After sintering at 150°C for 2min, surface resistance of the antenna reaches to 7.31Ω/sq and thickness of the silver layer is 466nm. Then, the antenna is treated at -40°C for 6h. Interestingly, the resistance of the antenna dropped by 9%, which may due to the limited motivation of PVP chain in relatively low temperature. In order to study its stability, the RFID antenna has been put into the night side, sunny side and room temperature for 30 days. The resistance is nearly the same as its original after 1 month, though some decreasing appeared. The result indicates that the antenna fabricated shows excellent stability and the working temperature can range from -40°C to 150°C.

Controllable and mono-disperse copper nanoparticles were synthesized via a simple chemical method which copper nitrate trihydrate, hydrazine hydrate and poly (vinylpyrrolidone) were used as copper source, reducing agent and capping agent, respectively. Copper nanoparticles so-prepared were characterized by UV-Visible spectroscopy, X-ray diffraction measurements (XRD), scanning electron microscopy (SEM). The colloid of the copper nanoparticles was obtained after washing and centrifuging by deionized water and acetone three times by which impurity ions can be removed. Suspension of nano-copper conductive ink for gravure printing was obtained by adding some solvent and additives. Then, samples were obtained by proofing and sintered under the nitrogen ambience. The resistance and thickness were measured. The result illustrated that the copper particles prepared have size about 80 nm and majority particles are spheroidal. The suspension of nano-copper conductive ink has 35.15% copper content according to thermal gravimetric analysis (TGA) and 1.29 % PVP. Surface resistance of samples proofing on polyimide film after sintering can reach 6.16 Ω/sq and the resistivity is 1.09×10-4 Ω·cm.

To reach the practical application of printable electronics based on the comparing of organic and inorganic nano conductive materials, high concentration nano metal such as silver, copper and their gravure or ink jet ink was prepared. The RFID antenna was printed with gravure printing and the packaging RFID was identified.