Carbon Conductive Paste 10g Tube
Carbon Conductive Paste is a highly viscous formulation of micro-graphite in a liquid carrier (some would say "solvent", but it is not really a solvent) for the preparation of porous samples destined for x-ray analysis (EDS). For samples like paper, thin fibers and fabrics, the higher viscosity of the Carbon Conductive Paste relative to the SPI Supplies Carbon Conductive Paint, results in far less potential for artifacts due to solvent exposure and solvent "wicking" up into the sample to be studied. Of course another alternative to consider, when mounting these kinds of samples, would be the popular double sided conductive adhesive tapes, sheets, and discs.
Conductivity considerations:
Obviously, the Carbon Conductive Paste is less conductive than the SPI Supplies Silver Paste Plus. However, when used in the SEM applications, and with micromicro amps of current, the difference in conductivity between the silver paste vs. carbon paste is far less than one might otherwise expect. What we mean is, while the silver paste does give a better result, most users find the incremental improvement is less than one might expect. We do not at the present time have actual resistivity values for this product.
Product purity:
The Carbon Conductive Paste, while not spectroscopically pure, is nevertheless pure enough so that for most users, one does not see any impurity elements from the paste, unless the electron beam is directly focused onto the paste itself.
The Carbon Conductive Paste, when analyzed for impurities, shows less than 10 ppm ash and in a majority of cases, no impurities are detectable energy dispersive spectroscopy (EDS) systems. We consider the critical impurities in this kind of product, from a production standpoint, to be silicon and sulfur and we can report that both are below the 10 ppm level. Other impurities, so far as we can determine, are all at or below ppm levels in the single digits.