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Invention and History of Eraser – Facts and Types. An eraser is an object used to remove pencil markings. It is known as an “eraser” in the United States and Canada and as “rubber” in the UK, India, Ireland, South Africa, Australia, and New Zealand.
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History of Pen and Ink. Pen is a general name for a writing...
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History. A pencil eraser. Before rubber erasers used today, tablets of wax were used to erase lead or charcoal marks from paper. Bits of rough stone such as sandstone or pumice were used to remove small errors from parchment or papyrus documents written in ink.
14 Μαρ 2019 · Learn about the history of pencils, erasers, sharpeners, markers, highlighters, and gel pens. See who invented and patented these writing instruments.
Eraser, piece of rubber or other material used to rub out marks made by ink, pencil, or chalk. The modern eraser is usually a mixture of an abrasive such as fine pumice, a rubbery matrix such as synthetic rubber or vinyl, and other ingredients. The mixture is processed and extruded and, if made.
In 1867, a hollow eraser, into which a pencil could be inserted, was invented by J. B. Blair of Philadelphia. Earlier versions are also known to have existed. In 1872, the Eagle company made pencils with erasers inserted directly into the wooden case of the pencil.
The science behind the pencil eraser is simple – the ‘stickiness’ of the eraser’s molecules is greater than that of the paper’s molecules and therefore the graphite marks made by the pencil are lifted from the page. Modern pencil erasers are made from a range of materials including plastic and foam.
13 Σεπ 2013 · Sept. 13, 2013. In 1858, a stationer named Hymen Lipman patented a newfangled pencil with a rubber plug embedded in one end of its wood shaft. An entrepreneur named Joseph Reckendorfer guessed...
