Source and application principle of stationery eraser

The pencil lead is made of graphite and clay. Graphite is soft and black. It is easy to adhere to paper, so it can write words. The rubber is very soft, with high friction and some stickiness. Wiping on the paper can stick the written words away without damaging the paper. Therefore, the pencil words can be wiped off with the rubber. If you write with a ball point pen, the ink will penetrate into the paper and it will not be easy to erase.

In 1770, Joseph Priestley, a British scientist, said: I saw a substance very suitable for erasing pencil strokes. At that time, rubber particles cut into small cubes were used throughout Europe to wipe away handwriting. This substance is called an eraser.

Edward naime, another British engineer, is believed to have invented the eraser in 1770. Before that, people used bread crumbs to erase handwriting. Naime said that he once picked up a piece of rubber as bread crumbs, but found it effective, so he began to produce and sell erasers.

The initial eraser is not convenient, because the unprocessed rubber is easy to rot. It was not until the inventor Charles Goodyear discovered in 1839 that vulcanization could improve the quality of rubber that the eraser became reliable.

In 1858, a man from Philadelphia obtained a patent for embedding an eraser in the tail of a pencil, but later the patent for the pencil with an eraser was cancelled because it was judged that "only two existing things are embedded together rather than a new product".

English name of eraser

In Britain and Australia, eraser is called rubber; But in the United States, rubber is one of the common names of condoms, and the name of eraser is eraser. This distinction is often used as a joke by Americans.

Today there are many kinds of erasers to meet different needs.

Some pencils have a small eraser at the end. Most of these erasers are pink, and the surface is smooth colloid. They perform well on most occasions, but sometimes they also make paper. If the force is too heavy, the eraser still has a chance to break the paper. When the handwriting is erased, the eraser leaves a residue on the paper. If not cleaned properly, these residues will leave traces on the paper.

Another kind of eraser is the brown eraser commonly used by artists. It is made of soft and rough rubber. It is designed to easily erase large areas of traces without breaking the paper. But this kind of eraser can not erase the handwriting effectively and accurately.

Another kind of eraser commonly used by artists is called soft eraser. It is mainly made of a kind of gray material and is rubbery with gum. Its strength allows it to leave no residue, so its life is longer than other erasers. It removes handwriting by "absorbing" graphite. This kind of eraser can not only erase the handwriting (in fact, it can accurately remove the handwriting), but also be used to highlight important parts or make the work more detailed. However, it is not good at removing large areas of handwriting, and if it is excessively heated, it will dirty or even stick to the paper.

The soft polythene eraser has the texture of plastic and has the same function as the ordinary pink eraser. These erasers are softer than pink erasers, so they are less likely to damage the paper. Polyethylene erasers are usually white.