A couple of interesting things about pencils and eraser

The indispensable stuff during school time.

In the age of modern technology, we have many electronic devices that can be used to record. However, it is not so that we leave the necessary basic items that we have used before. Pens, notebooks . are still consumed and used. Especially in it is pencil. Every year there are still billions of pencils consumed. It is not only a writing object but also a drawing. And the fact that people love to use the most pencil in all kinds of pens by writing and drawing things can be easily erased, edited. The tool used to erase the pencil is called a eraser. In this article we will learn about the eraser and its 'miraculous' function.

From the pencil

Speaking of purging, perhaps starting from the motivation to invent it, it's a pencil. There are many young people who still believe in one thing that pencils are made from lead. Fortunately, it's not like that, so if you swallow a piece of pencil, you won't have to worry about lead poisoning (even though this shouldn't happen). Exactly, the pencil is usually made of graphite and its compounds, Roman antiquity, professional religious scholars used metal rods called stylus to write on paper as words. papyrus bark.

Graphite graphite has been historically recorded for use since 1564. Industrial pencil lead is often made with a mixture of graphite and fine clay mixed with water to create long lead-intestinal fibers. The lead fibers are dipped in oil or wax and poured into the half-section of the grooved pen case. After that, the other half of the pen case is tied up and pressed. After that, this long lead is repainted and cut into pencils for sale. Modern European pencil hardness classification system is spread from 9H (hardest and lightest) to 9B (softest and darkest).

In the 1970s, NASA spent millions of dollars to study a pressure pen so astronauts could write in zero gravity. Meanwhile, the Soviets used a simpler method to achieve the goal of writing in zero gravity: using traditional pencils.

Until the eraser

And because of the need, half a century after the pencil was widely used, people began to study to produce a companion product that was bleaching. Stemming from the need to repair the lines from pencil writing, people began to think of an object capable of doing that. The first eraser was used hundreds of years ago, when people wrote in a hard pencil made of lead and tin - the bread intestines themselves. On April 15, 1770, Joseph Priestley used plant chewing gum to remove pencil marks, from which people began to invent bleach that closely resembled modernity. The idea of ​​sticking pencil and eraser is from Hyman L. Lipman in Philadelphia. This brought him wealth thanks to the sale of the invention patent in 1858 for $ 100,000. In the end, however, this patent was disabled because it was simply a combination of two inventions rather than an entirely new invention. Today, modern erasers are made of a mixture of cooking oil, pumice and sulfur - all bonded by rubber.

The use of bleaching is very simple, when you realize that you need to fix anything, you just need to sharpen it into that piece of paper, rub it hard. And as we see, the eraser will gradually fade out. Because of this ease, bleaching quickly became popular. An example of a highly versatile and commercially useful eraser was in 1955, when Walt Disney phoned William Diener about unpopular pencils in souvenir shops. at Disneyland. In that phone call, William Diener - as a bleaching industrialist - convinced Disney to put eraser in the form of Disney characters for sale. And then the business at Disneyland is greatly improved.

Some types of eraser

There are many different types of erasers. The type of eraser that comes with a pencil is also called an eraser, which is usually pink and contains hard rubber so sometimes using this type will scratch the paper and must use strong force to rub. Bleaching with white vinyl is much easier to remove than pink bleaching, so it is preferred later. Currently, almost all new pencils produced do not come with a pink eraser anymore. Another type of eraser is called kneading, it's soft and you can knead it in your hand. It absorbs graphite particles without much friction and leaves no stains, crumbs . Art eraser is the name of a soft eraser made from raw rubber. Its advantage is that it does not damage paper and erase it on a large area, but that drawback leaves behind too much. The color of this bleach is usually brown, sometimes blue.

In addition, because of the modern development, people also built electric eraser, electric eraser is a pen with buttons. When pressing the button, the eraser head will be rubbed at a consistent and consistent speed, helping to remove the easy and less scratching stain for the paper, which saves time.

Conclusion

Ever since invented until now. Eraser has always been used regularly and for children when going to school or architects, painters this is an indispensable item in daily work. In the near future, it is possible that the eraser will also retain its crucial position and be the companion of the pencil.