TECHNOLOGY FOCUS - ELECTRONICS - Preferred Process: In process (p1), the printing process involves drop on demand printing and the heating involves heating the precursor composition (C1) to a temperature of not greater than 300 (preferably 225, especially 185)degrees C to form the photovoltaic conductive feature. The process (p1) further involves high shear mixing the composition (C1); and surface modifying the substrate (preferably ceramic or polymer) with a laser. Preferred Components: The conductive feature comprises a set of finger lines and collector lines deposited essentially at a right angle to the finger lines in which either or both the parallel finger lines or the collector lines have width less than 200 (preferably 100) mu m. The conductive feature comprises a transparent conductive feature, indium-tin oxide or antimony-tin oxide, and metal-glass composition and is resistant to solder leaching. The heating sinters adjacent nanoparticles to one another.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The metallic nanoparticles are spherical and have an average particle size of not greater than 100 (preferably 10-80, especially 25-75) nm. At least 70 vol.% of the nanoparticles are not greater than twice the average particle size. The metal is a silver, palladium, copper, gold, platinum or nickel. The metallic nanoparticles comprise a cap or coating on it. The cap or coating comprises an inorganic cap or coating (preferably silica or glass), organic cap or coating or polymer. Preferred Composition: The composition (C1) further comprises metal oxide particles, glass particles and metal precursor compound.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The cap or coating comprises polymer selected from an intrinsically conductive polymer, sulfonated perfluorohydrocarbon polymer, polystyrene, polystyrene/methacrylate, sodium bis(2-ethylhexyl)sulfosuccinate, tetra-n-octyl-ammonium bromide, alkane thiolate and polyvinyl pirolydone. EXAMPLE - No suitable example given.