pyyhekumit

Pyyhekumit, commonly known as erasers, are tools used to remove pencil marks from paper. They are typically made of a pliable material, such as rubber, vinyl, or a synthetic polymer, which is able to pick up graphite particles from the paper's surface through friction. The effectiveness of a pyyhekumi depends on its composition and the type of graphite used. Some erasers are designed to be gentle on paper, while others are more abrasive and can remove marks more thoroughly but may also damage the paper if used too vigorously.

There are various types of pyyhekumit available. Kneaded erasers, often made of a putty-like substance, are pliable and can be molded into different shapes to erase specific areas or create highlights. Vinyl erasers are known for their ability to create clean erasures without leaving much residue. Rubber erasers, one of the oldest types, are durable but can sometimes smudge or leave marks. Electric erasers utilize a rotating tip to remove graphite, offering a precise and efficient way to erase, though they require a power source.

The history of the pyyhekumi dates back to the discovery of vulcanized rubber by Charles Goodyear in 1839. Before that, people used bread crumbs or other soft materials to erase pencil marks. The modern pyyhekumi quickly became an essential tool for artists, students, and anyone who worked with pencils, revolutionizing the way mistakes could be corrected in writing and drawing.