Small conductive tracks are created by direct inkjet-printing of an ink with 30 nm silver particles onto flexible and transparent untreated polyarylate foils with a low surface energy. Lines with a diameter as narrow as 40 micrometers are obtained. After sintering, the conductivity of the obtained silver tracks is 13 to 23 % that of bulk silver. Such direct inkjet-printing may be applied in plastic electronics, where prestructuring or pretreatment of the substrate should be avoided to reduce production costs.