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Dielectrics are a critical element of all electronic devices, being used not only directly in the gate layer of transistors, but also as insulators separating conducting interconnects, as well as passivation/protective layers. Crosslinkable and polymeric organic dielectrics can form large-area, highly uniform, and smooth films, which are highly flexible and solution processable, strong advantages for their use in flexible organic electronics. However, for the most challenging application of the gate dielectric, any material must ideally enable the formation of functional and stable films of thickness > 100 nm. This is driven by two requirements. First, low voltage operation, typically > 5 V, is due to the battery supply in portable applications along with integration of inputs and outputs with silicon based complementary metal-oxide-semiconductor (CMOS) technology. For some biomedical sensors, there is the additional constraint of the electrochemical window of water (1 V). Second, the channel length L to dielectric thickness d ratio required to achieve transistor saturation (typically L/d >> 10) is a requirement for use in digital logic applications. Short channel lengths are needed for high frequency operation, and hence with the resolution limit of conventional photolithography being of order of micrometers, dielectric thickness needs to scale accordingly into the sub-100 nm range.There has been considerable activity toward the development of printed organic field effect transistors (OFETs). Hubler and Ellinger published three reports on fully printed transistors on foil, [3][4][5] where they used only additive techniques such as screen, gravure, and flexographic printing to fabricate piezoelectric loudspeakers based on transistors in a roll-to-roll process. Miniaturization of transistor devices using roll-to-roll compatible methods for fabrication has also been another important trend over the last couple of years. Vilkman et al. demonstrated the complete roll-to-roll manufacturing of self-aligned transistors with 25-70 µm channel lengths. [1] The authors used a combination of flexography, gravure printing, metal evaporation combined with lift-off and photolithography to produce ≈80 m of plastic foil with thousands of devices. Higgins et al. used printing and nanoimprint lithography to fabricate selfaligned transistors and inverters with sub-micrometer channel length in a batch process. [6] The dielectric and semiconductors were deposited with forward gravure and/or inkjet printing. Kang et al. scaled transistor dimensions by gravure printing 10 µm lines for gate electrodes with self-aligned source-drain electrodes. [7] Park et al. reported printing silver electrodes in Organic electronics requires dielectrics which can be processed over large areas at low temperature in ambient using simple solution based techniques. Here a crosslinkable acrylate-based organic dielectric is reported, which is gravure printable on plastic substrates, patternable by conventional photolithography, and can form electrically funct...

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