eraser is used to rub the written words by pencil. An eraser (US) or rubber (UK) is an article of stationery that is used for rubbing out pencil markings. Erasers have a rubbery consistency and are often white or pink, although modern materials allow them to be made in any color. Many pencils are equipped with an eraser on one end. Typical erasers are made from synthetic rubber, but more expensive or specialized erasers can also contain vinyl, plastic, or gum-like materials. Other, cheaper erasers can be made out of synthetic soy-based gum.
Prior to the invention of the rubber eraser, tablets of rubber/wax were used to erase lead/charcoal marks from paper. Bits of rough stone such as sandstone or pumice were used by various cultures to remove small errors from parchment or papyrus documents written in ink. Crustless bread was used as an eraser in the past; remembering school days in the College of Engineering in Meiji Tokyo, a student claimed: “Bread erasers were used in place of rubber erasers, and so they would give them to us with no restriction on amount. So we thought nothing of taking these and eating a firm part to at least slightly satisfy our hunger.” [1]
On April 15, 1770, Joseph Priestley described a vegetable gum which had the ability to rub out pencil marks: "I have seen a substance excellently adapted to the purpose of wiping from paper the mark of black lead pencil." He dubbed the substance "rubber".[2][3]
In 1770, Edward Nairne, an English engineer, is credited with developing the first widely-marketed rubber eraser for an inventions competition. He reportedly sold natural rubber erasers for the high price of 3 shillings per half-inch cube. According to Nairne, he inadvertently picked up a piece of rubber instead of breadcrumbs, discovered rubber's erasing properties, and began selling rubber erasers. Incidentally, this was the first practical application of the substance in Europe, and rubbing out the pencil marks gave it its English name.
However, rubber in its raw form shared the same inconveniences as bread, since it was perishable and would go bad over time. In 1839, inventor Charles Goodyear discovered the process of vulcanization, a method that would cure rubber and make it a durable material. Rubber erasers became common with this advent of vulcanization.
On March 30, 1858, Hymen Lipman of Philadelphia, USA, received the first patent for attaching an eraser to the end of a pencil. It was later invalidated because it was determined to be simply a composite of two devices rather than an entirely new product.[4]
Erasers come in several shapes and sizes. In addition to those that come attached to pencils, they may also be rectangular blocks (block and wedge eraser), or conical caps that can slip onto the end of a pencil (cap eraser). A barrel or click eraser is a device shaped like a pencil, but instead of being filled with pencil lead, its barrel contains a retractable cylinder of eraser material (most commonly soft vinyl). Novelty erasers are made in a wide variety of shapes, colors, and designs to suit their themes (such as musical notes, animals, confectionery), and they are typically acquired more for their decorative nature than for any practical use, as the hard vinyl they are made from tends to smear heavy markings.
Prior to the invention of the rubber eraser, tablets of rubber/wax were used to erase lead/charcoal marks from paper. Bits of rough stone such as sandstone or pumice were used by various cultures to remove small errors from parchment or papyrus documents written in ink. Crustless bread was used as an eraser in the past; remembering school days in the College of Engineering in Meiji Tokyo, a student claimed: “Bread erasers were used in place of rubber erasers, and so they would give them to us with no restriction on amount. So we thought nothing of taking these and eating a firm part to at least slightly satisfy our hunger.” [1]
On April 15, 1770, Joseph Priestley described a vegetable gum which had the ability to rub out pencil marks: "I have seen a substance excellently adapted to the purpose of wiping from paper the mark of black lead pencil." He dubbed the substance "rubber".[2][3]
In 1770, Edward Nairne, an English engineer, is credited with developing the first widely-marketed rubber eraser for an inventions competition. He reportedly sold natural rubber erasers for the high price of 3 shillings per half-inch cube. According to Nairne, he inadvertently picked up a piece of rubber instead of breadcrumbs, discovered rubber's erasing properties, and began selling rubber erasers. Incidentally, this was the first practical application of the substance in Europe, and rubbing out the pencil marks gave it its English name.
However, rubber in its raw form shared the same inconveniences as bread, since it was perishable and would go bad over time. In 1839, inventor Charles Goodyear discovered the process of vulcanization, a method that would cure rubber and make it a durable material. Rubber erasers became common with this advent of vulcanization.
On March 30, 1858, Hymen Lipman of Philadelphia, USA, received the first patent for attaching an eraser to the end of a pencil. It was later invalidated because it was determined to be simply a composite of two devices rather than an entirely new product.[4]
Erasers come in several shapes and sizes. In addition to those that come attached to pencils, they may also be rectangular blocks (block and wedge eraser), or conical caps that can slip onto the end of a pencil (cap eraser). A barrel or click eraser is a device shaped like a pencil, but instead of being filled with pencil lead, its barrel contains a retractable cylinder of eraser material (most commonly soft vinyl). Novelty erasers are made in a wide variety of shapes, colors, and designs to suit their themes (such as musical notes, animals, confectionery), and they are typically acquired more for their decorative nature than for any practical use, as the hard vinyl they are made from tends to smear heavy markings.
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