Word: selenium
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Dates: during 1960-1969
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...that needs no chemicals, can duplicate anything from grease pencil to ballpoint pen, though it is more successful in copying type than photographs. The 914 makes copies by projecting the image of the original document or object onto an electrostatically charged drum coated with a sensitive element called metallic selenium. The machine automatically sprinkles the drum with a black powder that adheres to the dark portions of the image; the drum then rolls the powder onto the paper, which is also electrostatically charged. A quick blast of heat fixes the powder permanently to the paper...