Silver-based ink

Most of the conductive IJ inks that are commercially available today, and a majority of the development work being performed as of 2008, utilize silver-based inks for reasons discussed later in this article. Major applications in printed electronics which are currently the focus of significant development work with conductive inkjet inks are summarized in Table 1... 

Reported volume resistivities for printed patterns formed from commercial silver-based inks are higher than that of bulk silver. This occurrence reflects the fact that sintered ink patterns contain non-ideal defects such as incomplete particle-to-particle contact, incomplete sintering between contacting particles, residual porosity, and the presence of non-conductive additives. The morphology and extent of void formation in two representative sintered silver nanoparticle inkjet inks are illustrated in Fig. 1. 

The silver-based ink (Electrodag PF 410) and the graphite-based ink (Electrodag 423 SS) Acheson (Milan, Italy). The insulating mono-component ink (Vinylfast 36-100) Argon Italiana (Milan, Italy). 

Solution processable conductors come in three main elasses metals, metal oxides or organics. Printed metals, most notably as eleetrodes or RFID antennae, are mainly obtained by using partiele-based inks. Silver or gold partiele inks are eommercially available. Evonik has developed silver printing pastes, sueh as Silver 30 SN, a formulation of silver flakes in organie solvents, optimized for screen printing (Figure 2.6). 

Multilayer conductor patterns can be used with copper conductors. The design of the conductors and dielectrics is the same as witir gold and silver-based thick-film inks. However, the dielectric materials used for copper inks are specially formulated for firing in a nitrogen atmosphere with low oxygen content. The copper via-fill materials used with copper conductors are also specially formulated. 

Although the percentage difference in the two calculations is rather significant, the overall thermal resistance in the copper thick-film can be considered negligible. If the thick-film ink were silver-based instead of copper-based, then the thermal resistance degradation would be considerably less. 

Magdassi, S., A. Bassa, Y. Vinetsky, and A. Kamyshny. 2003. Silver nanoparticles as pigments for water-based ink-jet inks. Chem. Mater. 15 (11) 2208-2217. 

The LEC structure that involves the addition of ionic dopants and surfactants to the printable inks enables the ability to print a top electrode without restriction by the work function of the metal. Silver, nickel, or carbon particle-based pastes are generally the preferred printable electron injecting electrodes however, the shape and size of the particles combined with the softening properties of the solvent can create electrical shorts throughout the device when printed over a thin polymer layer that is only several hundred nanometers thick. For optimal performance, the commercially available pastes must be optimized for printing onto soluble thin films to make a fully screen-printed polymer EL display. 

UV curable flexo ink for RFID antennas Radio frequency identification (RFID) devices and contactless smart cards are capable of uniquely identifying an individual or object when they are interrogated by an external radio frequency signal. Recently, a process of printing with the use of UV curable conductive flexo inks has been introduced. The inks are based on polyfunctional acrylates with silver flakes added for the electrical conductivity. The advantages of these inks are ... 

NADH can be readily monitored electrochemically, and can be used as a simple and effective method to monitor metal ion concentrations. Such an approach has been recently utilised by Rodriguez et al. [149] for an SPCE-based biosensor for the amperometric detection of Hg2+, Cu2+, Cd2+, Zn+ and Pb2+. Devices used in this study were printed onto 250 pm thick polyester sheet. The working electrode (planar area 0.16 cm2) was fabricated from a commercially available carbon powder containing 5% rhodium plus promoters, which was made into a screen-printable paste by mixing 1 4 in 2.5% (w/v) hydroxyethyl cellulose in water. The reference electrode ink contained 15% silver chloride in silver paste. The counter electrode and basal tracks were fabricated... 

The inks for screen-printing the electrodes contain the sub-micron metal powder, either a Ag-Pd alloy or a base metal, usually nickel (melting point, 1455°C) but sometimes copper (melting point 1084°C). Palladium (melting point, 1554°C) and silver (melting point, 961 °C) form solid solutions with melting points approximately proportional to the content of the end members. 

Obviously, one of the major concerns in the preparation of the conductive ink is the need for low electrical resistivity. Commercial conductive IJ inks based on silver particles have metal loadings ranging from approximately 20% to 80% by weight. Resistance of a pattern printed from a single pass of a print head is thus expected to be lower for formulations with higher sohds content. However, another factor that influences resistivity is the non-conductive organic load in the ink and in the sintered pattern. Therefore, when choosing... 

The tag produces an identification (ID) signal, i.e., a radio frequency (RF) signal carrying identification information, capable of being interpreted by an electronic reader device. A preferred tag is fabricated using a printing process to mark a conductive pattern, e.g., comprised of a conductive ink based on silver, carbon, etc., on a flexible substrate, e.g., polyvinyl chloride. In at) -ical application, the flexible substrate is then preferably used to form a wrist band that can be used to identify an individual to permit, deny or otherwise determine the level of access to an area, e.g., a concert, a work area, or other restricted enviromnent. 

Chem. Descrip. Silver chloride/titanium dioxide composite (JMAC component) with sodium dioctyl sulfosuccinate, ethanol, and water Uses Preservative for in-can presenration of water-based paints, inks, wood finish prods., cosmetics food-contact applies. 

Uses Metallic pigment for soiv.-based Iiq. inks Features Extra high brilliance Properties Silver pellets easily disp. 11 pm particle size Rotosafe 760 003 [Eckart-Werke]... 

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