Inks for Slot-die Coating of Organic Solar Cells Thorough scientific understanding of active materials design and ink development has been generated at infinityPV through extensive research in large scale processing of OPV. This has led to the development of active layer materials, known as Production Ink (PI), that are optimized for the processing techniques and technical requirements in large scale roll-to-roll (R2R) fabrication. Furthermore, an understanding of the delicate interaction between the ink, the slot-die coating head, the machinery and the properties of the solar cells has been generated and R2R compatible inks are now offered to our customers. Specifications Standard photovoltaic parameters for R2R produced inverted devices and ink prices. Voc(V) Jsc(mA/cm2) FF (%) PCE (%) Price (1000 ml) PI-1 ~0.55 ~6 ~55 1.5-2 4.595 € PI-2 ~0.7 ~6 ~50 >2 5.295 € PI-3* ~0.8 ~8 ~50 >3 5.795 € PI-4* ~0.75 ~10 ~55 >4 6.995 € PI-5* ~0.8 ~10 ~60 >5 9.590 € PI-6* ~0.8 ~12 ~65 >6 12.250 € Designed for Slot-die Coating The different Production Inks from infinityPV are developed for and tested in a large scale production environment applying roll-to-roll slot-die coating and printing of all layers under ambient conditions on ITO-free substrates. Common to the inks is their ability to yield highly uniform dry films, their robustness in the production and their high performance applying thick active layers (> 400 nm) which makes them perfect for large scale production of OPVs on flexible substrates. The inks come preformulated from infintyPV which includes donor:acceptor ratio, solvent combination, active material loading and viscosity, all optimized for slot-die or blade/knife coating on flexible substrates applying an inverted geometry device structure. R2R slot-die coating of different Production Inks. All Production Inks are produced by infinityPV Production Inks from infinityPV are offered in several different versions which allow our customers to choose the right ink for their particular purpose and project. Our standard inks are formulated in halogenated aromatic solvent mixtures (other solvent formulations available upon request). Standard photovoltaic parameters based on each ink are listed in the table and is intended as a guideline for our customers and numbers should therefore not be seen as absolute values. The inks are supplied in a minimum volume of 25/100 ml in containers up to a volume of 1000 ml. It is our experience that approximately 100 ml of active layer ink is needed in order to allow for the fabrication of an entire set of large scale OPV devices by R2R processing. The inks have a long shelf life (> 1 year) provided that they are stored in the dark, at < 25 °C and under inert atmosphere. Prior to application the ink solution may need heating at 100 °C followed by filtering.
