What is eraser made of
They used rubber or wax tablets to remove traces from the paper. They used rough material, such as sandstone or pumice, to strip ink from parchment or papyrus. Soft bread was used in Japan. That year, Edward Nairne , an English inventor, discovered that a piece of rubber would remove pencil marks instead of breadcrumbs.
In , inventor Charles Goodyear patented the vulcanization process of curing rubber, which solved the problem. Rubber became more resilient as a result of this operation, and the eraser became a household object. Hymen Lipman patented a method of applying an eraser to the end of a pencil, but the patent was later revoked. Kneaded erasers may be molded into a fine point to erase small data, a wider surface to use as a sticker, or a blotter to lighten a darker graphite-covered patch.
Poster putty resembles a kneading eraser but has a significantly higher lifting power and erases the substance by lifting graphite off it. It should not smudge or harm work in progress because of the way it operates. In other ways, it functions similarly to a kneaded eraser. Simply put, eraser molecules are stickier than paper molecules, because when the eraser is rubbed over the pencil point, the graphite sticks to the eraser rather than the paper. Sign up for our Newsletter! Mobile Newsletter banner close.
Mobile Newsletter chat close. Mobile Newsletter chat dots. Mobile Newsletter chat avatar. Mobile Newsletter chat subscribe. Everyday Innovations. How do erasers erase? Erasers have come a long way since the early days of using moist bread to eradicate errors.
Use erasers to remove graphite, ink Did You Know? Related Articles How do they get lead in a wooden pencil? Sources Conley, Gregory. Patent and Trademark Office. Page Cite This! Although the sculpture is made from stainless steel and fiberglass, the symbolic rubber wheel was begging the question, "What is an eraser? Although there are felt-pad chalkboard and white board erasers, the essence of an eraser is a plain piece of rubber--"graphite grabbers," some people in the industry like to call them.
Even so, there are many types of these erasers, including handheld flat rectangles, cylindrical plugs attached to a pencil, or caps that fit over the end of a pencil. There are also all sorts of colorful novelty erasers in various geometric shapes with holiday, animal, sports, and other motifs. It begins with the development of the pencil. At first, unwanted pencil marks were rubbed off with a ball of moist bread and probably other similar materials. In , the proceedings of the French Academy of Sciences noted that caoutchouc condensed latex obtained from the Hevea brasiliensis rubber tree could be used to erase pencil marks.
The first scientific description of caoutchouc had come during a French geographic expedition to South America in The name rubber was given to caoutchouc in , and is attributed to none other than British-American chemist Joseph Priestley. He noted that caoutchouc was useful to "rub out" pencil marks; hence the name rubber was born.
In most parts of the world, erasers are still called rubbers. There was a drawback to the early erasers--and all materials made from rubber--since the rubber softened during warm weather, became hard in cold weather, and was stinky as it started to degrade. Enter hardware merchant-turned-chemical engineer Charles Goodyear, who, after several years of work, developed the vulcanization process to cure rubber in During vulcanization, sulfur is added to rubber and the mixture is heated under pressure to form sulfur cross-links between the rubber's polymer chains.
The cross-links increase the strength, stability, and elasticity of the rubber. After Goodyear's discovery, rubber became broadly used for many common items, including erasers.
The first patent on a combined pencil and rubber eraser was granted in the U. Most pencils made for use outside the U. It is biosynthesized in the rubber tree from 3-methylbutenyl pyrophosphate, an important building block for many natural compounds.