- Petroleum processing plants transport synthetic rubber in powder or liquid form to rubber factories. If natural rubber is to be used, it comes in strong bulks, which workers must first crush and dissolve.
- Mix rubber with ground pumice powder (which makes rubber slightly harder), iron oxide (which turns rubber pink), vegetable oil, sulfur and other substances.
- Heating the mixture causes sulphur to mix with rubber to increase the strength of rubber and make it more durable.
- Feed the soft and still warm material into the punch (squeeze into a die) and make a long and thin rubber stick. Cut the rubber stick into small pieces with a knife. After it cools down, it is transported to the pencil factory to make the eraser on the pencil.
- The block eraser used alone is made by injecting heated rubber mixture into various shapes of moulds. When it’s cooled, open the mould, and all kinds of erasers come out.
Nowadays, there are many kinds of erasers to meet different needs.
Some pencils have a small eraser at the end. These erasers are mostly pink and have a smooth gum surface. They perform well on most occasions, but if they are too hard, the eraser will break the paper. When the handwriting is erased, the eraser leaves residue on the paper. If not cleaned up properly, these residues will leave traces on the paper (Note: This is more in 2004, all polyethylene rubber and non-gelatinized red rubber. If you buy a Chinese pencil, it will be found that the rubber is gelatinous or loose, absolutely false).
Another kind of eraser is the brown eraser commonly used by artists, which is made of soft and rough rubber. Its design is easy to erase large areas of traces, and will not break the paper. But this eraser can’t erase handwriting effectively and accurately.
Another kind of eraser commonly used by artists is called soft eraser. It is mainly made of a gray material and is acorn to gum. Its strength prevents it from leaving residue, so its life is longer than other erasers. It removes handwriting by “absorbing” graphite. This eraser can not only erase handwriting (in fact, it can remove handwriting accurately), but also be used to highlight important parts or make works more detailed. However, it is not good at removing large areas of handwriting, and if overheated, it will dirty or even stick to paper.
Soft polyvinyl erasers have a plastic texture and the same function as ordinary pink erasers. These erasers are softer than pink erasers and therefore less vulnerable to paper damage. Polyethylene erasers are usually white.
The eraser used by the students is fragrant. This fragrance is a volatile oil. If plastics and erasers are put together for a long time, the volatile oil (organic solvent) from erasers can dissolve plastic in a small amount, which causes the erasers we see to corrode on stationery.
Because of the softness and structure of the eraser. In home life, erasers can be used to remove some stains. For example, a computer memory strip can be cleaned with a dry, soft eraser. Take an eraser and rub it up and down a few times so that the dirt on the phone shell can be easily removed.