Alexandra Pekarovicova

Gravure Printing of Conductive Inks on Glass Substrates for Applications in Printed Electronics

In graphics, gravure printing is the preferred method for printing high quality, fine dimension graphics using high-speed roll-to-roll or sheet fed presses. Gravure printing typically employs flexible and compressible substrates such as various papers and polymer films. In electronics, glass substrates are a common, if not preferred, substrate in many applications, particularly displays and photovoltaics. In combining printing with glass substrates, challenges exist in adapting contact-based printing methods such as gravure to the mechanical properties of the more rigid substrates. In this work, sheet-fed gravure printing has been successfully used to print silver-based conductive inks on glass substrates. Various features were designed and printed to evaluate conductive layers in terms of their printability and electrical performance. The independent variables include gravure cell dimensions, trace orientation with respect to printing direction and ink type. Results from this work provide an insight into the science of gravure printing on glass by correlating the independent variables to printed feature quality and electrical performance.

Printing Ink Formulations

This chapter is focusing on individual ink components. Inks may be comprised of main components, such as pigments to add color, resins or polymers to disperse the pigment, and carry the ink to the substrate and anchor it there. Usually, resins or polymers have to be dissolved in the solvent. Depending on type of the solvent, inks may be solvent-based or water-based. Obviously, there may be thermoplastic hot melt inks, and energy curable UV or EB inks. The former group uses melted polymer as an ink carrier, and the later is taking advantage of low-viscosity monomers and prepolymers, which eventually become polymers. This chapter is then introducing pigment dispersing and making finished ink. Selected ink formulations are discussed. Attention is concentrated on the difference between water-based solution and emulsion resins. The difference between colored and functional inks is highlighted. In conclusion, this chapter is briefly introducing functional inks for printed electronics.

Enhancement of Wheat Straw Enzymatic Hydrolyzability by Low Temperature Pretreatments

Enhancement of Wheat Straw Enzymatic Hydrolyzability by LowTemperature Pretreatments By Alexandra Pekarovicovä^.Vlasta Luzäkovä,Vladimir Reiser* and Jan Pekarovia Ustav biotechnologie SV§T, Kollärovo näm. 9, 812 37 Bratislava,Tschechoslovakia. 2) Chemickotechnologickä fakulta SVST, Radlinskeho 9, 812 37 Bratislava, Tschechoslovakia. 3) Vyskumny ustav papiera a celulozy, Lamaöskä 3, 815 20 Bratislava,Tschechoslovakia.

The characterisation of surface treated silica-filled and non-filled polydimethylsiloxane films

In this work, various methods to enable tailoring of polydimethylsiloxane film surfaces are implemented and compared to determine their influence on surface energy and roughness. Films were prepared containing various levels of hydrophilic silica filler. Ultraviolet-ozone, and Piranha solution treatments were also implemented and characterised. Lastly, the combination of both silica filler and treatments were utilised and characterised to understand interactive effects. Influence of filler loading, and surface treatment on roughness, and surface energy of films was determined. Regardless of surface treatment, addition of silica significantly influences total surface energy. Addition of silica influenced total surface energy of the films by itself, and in combination with the Piranha and UV-ozone treatments. The lowest surface energy was that of the control Polydimethylsiloxane film 21.5 N/m. The overall highest surface energy achieved was that of the 10% filled 30-minute Piranha solution treated sample, having a surface energy of 44.1 N/m.