An eraser or rubber is an article of stationery that is used for removing pencil and sometimes pen writings. Stationery has historically meant a wide gamut of materials Paper and Office supplies, Writing implements Greeting cards etc A pencil is a Writing or Drawing instrument consisting of a thin stick of Pigment (usually Graphite, but can also be coloured pigment or A pen (Latin pinna, feather is a Writing instrument used to apply Ink to a surface usually Paper. Erasers have a rubbery consistency, and they are often white, brown or pink although with modern materials they can be of any color. Many pencils are equipped with an eraser on one end. Typical erasers are made of synthetic rubber, but more expensive or specialized erasers can also contain vinyl, plastic, or gum-like materials. A vinyl compound is any Organic compound that contains a vinyl group (also called ethenyl) &minus C[[Hydrogen H]] =CH sub>2 Plastic is the general common term for a wide range of synthetic or semisynthetic organic solid materials suitable for the manufacture of industrial products Natural gums are Polysaccharides of natural origin capable of causing a large Viscosity increase in solution even at small concentrations Other more inexpensive erasers can be made out of synthetic soy-based gum.
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History
Prior to the invention of the rubber eraser, tablets of wax would be used to erase lead/charcoal marks from paper. Some people claim that white bread (without crust) would be used as an eraser along with wax tablets, this would work effectively, but the bread would disintegrate, and would be too costly to replenish. [1]
In 1770, Edward Nairne, an English engineer, is credited with creating the first rubber eraser because he heard that there was a competition for the entire world, to see who could have the best innovation. Edward Nairne b Sandwich, England, 1726 d London, September 1 1806, was an optician and scientific instrument maker 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. Charles Goodyear ( December 29, 1800 - July 1, 1860) was the first American to vulcanize rubber, a process which he discovered in Vulcanization (or Vulcanisation refers to a specific curing process of Rubber involving high heat and the addition of Sulfur or other equivalent curatives 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. Events 240 BC - 1st recorded Perihelion passage of Halley's Comet. Year 1858 ( MDCCCLVIII) was a Common year starting on Friday (link will display the full calendar of the Gregorian Calendar (or a Common Hymen L Lipman is credited with registering the first patent for a Pencil with an attached Eraser on March 30, 1858 ( Philadelphia (ˌfɪləˈdɛlfiə The United States of America —commonly referred to as the A patent is a set of Exclusive rights granted by a State to an inventor or his assignee for a fixed period of time in exchange for a disclosure of an It was later invalidated because it was determined to be simply a composite of two devices rather than an entirely new product [2].
Types
Erasers are often found on the end of a pencil opposite the graphite point. The type of eraser often attached to pencils is usually pink, red or green, and has a smooth, rubbery texture. Erasers also come in many different colors to match the pencil to which they are attached, especially for novelty purposes. Pulverized pumice is blended into this type of eraser to make it abrasive. Pumice is a textural term for a volcanic rock that is a solidified frothy lava composed of highly microvesicular glass Pyroclastic with very thin translucent It is good for most erasing purposes, though it tends to smear and can damage the paper if used too heavily. It leaves eraser residue that must be brushed away; care must be taken in brushing away residue, as the eraser particles can leave marks on the paper. Some erasers do not erase well because they lack the flexibility to clear the paper of the pencil markings.
Another eraser type that is popular with artists is the art gum eraser, made of soft, coarse rubber. It is especially suited to removing large areas, and does not damage the paper. As gum erasers tend to crumble as they are used, this type leaves a lot of eraser residue, however, and is not very precise. Many artists use a broad brush to sweep away the loose eraser residue. Art gum erasers are commonly tan or brown.
The kneaded eraser (or kneaded rubber eraser) is also well-known among artists. See also Eraser The kneaded eraser (or putty rubber) is a tool for Artists. The definition of an artist is wide-ranging and covers a broad spectrum of Activities to do with creating Art, practicing the Arts and/or demonstrating It is usually made of a grey or white pliable material that resembles putty or chewing gum. Putty is a generic term for a plastic material similar in texture to Clay or Dough typically used in domestic construction and repair as a sealant or filler For songs called "Chewing Gum" see Chewing Gum (song Chewing gum is a type of Confectionery traditionally made of Chicle It functions by "absorbing" and "picking up" graphite and charcoal particles. The Mineral graphite, as with Diamond and Fullerene, is one of the Allotropes of carbon. Charcoal' is the blackish residue consisting of impure Carbon obtained by removing water and other volatile constituents from Animal and Vegetation It does not wear away and leave behind eraser residue, thus it lasts much longer than other erasers. Kneaded erasers can be shaped with the fingers and used for precision erasing, to create highlights, or for detailing work. It is commonly used to remove light charcoal and light graphite marks in subtractive drawing techniques. However, it is not well-suited to completely erasing large areas, and may smear or stick if it becomes too warm. Though it does not wear away like other erasers, it can become exhausted, unable to absorb any more graphite or charcoal in which case it will start to smear and actually make marks instead of erasing them.
Soft vinyl erasers have a plastic-like texture and erase cleaner than standard pink erasers. A vinyl compound is any Organic compound that contains a vinyl group (also called ethenyl) &minus C[[Hydrogen H]] =CH sub>2 They are somewhat softer and non-abrasive, making them less likely to damage canvas or paper. They are prone to cause smearing when erasing large areas or dark marks, so are more frequently used for erasing light marks and precision erasing. Engineers favor this type of eraser for work on technical drawings due to their gentleness on paper. A technical drawing is a form of graphic communication This type of Drawing is used in the transforming of an idea into physical form Vinyl erasers are commonly white.
Another type of eraser is used specifically for marks on a chalkboard or whiteboard. A chalkboard or blackboard is a reusable Writing surface on which text or drawings are made with sticks of Calcium sulfate, known when used for this A whiteboard (also known as a markerboard, dry-erase board dry-wipe board or a pen-board) is a name for any glossy surface most commonly colored Rather than being rubbery or gummy like pencil erasers, it is a hand-held wooden or plastic block with a dark felt pad on one side. Felt is a non-woven cloth that is produced by matting condensing and pressing fibers
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 vinyl). A pencil is a Writing or Drawing instrument consisting of a thin stick of Pigment (usually Graphite, but can also be coloured pigment or 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.
References
Notes
- ^ Petroski. pp. 31
- ^ Reckendorfer v. Faber 92 U.S. 347 (1875)
Bibliography
- Petroski, Henry (1990). The Pencil: A History of Design and Circumstance. New York: Alfred A. Knopf. ISBN 0-394-57422-2.
See also
External links
- Eraser: How Products are Made, Volume 5 (1997) by Rose Secrest
- Effects of Eraser Treatment on Paper by E. An ink eraser is an instrument used to remove ink from a writing surface J. Pearlstein, D. Cabelli, A. King and N. Indictor. Journal of the American Institute for Conservation. 1982, Volume 22, Number 1, Article 1 (pp. 01 to 12)
- Goodyear Rubber History
- All about erasers: history, classification, photo, collection
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