Typewriter
Erasable bond

Paper companies produced a special form of typewriter paper called erasable bond (for example, Eaton's Corrasable Bond). This incorporated a thin layer of material that prevented ink from penetrating and was relatively soft and easy to remove from the page. An ordinary soft pencil eraser could quickly produce perfect erasures on this kind of paper. However, the same characteristics that made the paper erasable made the characters subject to smudging due to ordinary friction and deliberate alteration after the fact, making it unacceptable for business correspondence, contracts, or any archival use.
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