The First Erasers
- Long before the discovery of latex, humans used bread to remove pencil marks from paper. It was readily accessible and seemed to do the job better than any other substance.
The Eraser Breakthrough
- The discovery of latex from rubber trees in South America in the 1700s, ushered in a revolution for removing pencil marks. This new substance, which could "rub out" pencil marks, was initially called a "rubber" and was the predecessor to what we now call the "eraser."
- Early erasers hardened with the cold, melted with the heat and emitted an unpleasant odor. With the development of vulcanization, the curing of rubber, by Charles Goodyear in 1839, these problems were solved.
Modern Materials in Erasers
- The primary ingredient in erasers today is a rubber--either natural or synthetic. Natural rubber is still harvested from rubber trees, while synthetic rubber is a compound most often derived from styrene and butadiene. Sulphur is added during the curing process. Finally, additional ingredients may be added such as vinyl, colorants for attractiveness, pumice for added grit and vegetable oil for workability.
- Today's erasers come in all shapes and sizes, from the tiniest pink cylinder on top of a pencil to great chunky trapezoids, and colorful kid-friendly animals shapes to malleable globs of gray putty. Most are used to rub out marks left by graphite pencils, but others can be used to remove special erasable ink.
Pencils without erasers
- While it's hard to imagine a basic pencil without an eraser on top, there was a time when a pencil was just a pencil. Pencils with an eraser on top were invented by Philadelphian Hyman L. Lipman in 1858.