Eraser History of creation The inhabitants of South

Eraser

History of creation The inhabitants of South America discovered a lot of useful properties of white latex, which produced an evergreen plant of hevea. The natives called it a "weeping tree. " White latex they used for fixing to the body of jewelry and making dishes.

O On April 15, 1770, Joseph Priestley, a British natural scientist, noted in his diary that he had found material that was ideal for erasing inscriptions with pencil on paper. Priestley called it «rubber» . O In honor of this event on April 15, there is an international unofficial Day for erasers.

O Of course, pieces of rubber had to go a long way to improve before becoming an everyday item. The fact is that initially this material gave off an unpleasant smell and products from it softened in the summer and became too hard in winter. O In 1839, the American scientist Charles Goodyear mixed rubber with sulfur, which became a significant step on the evolution of the eraser. Goodyear invented the process of vulcanization, which significantly improved the quality and strength of the material obtained from natural rubber.

Modern production of erasers O Now erasers are made from natural or synthetic or even raw rubber, plastic and vinyl. O Vulcanization of natural rubber produces a strong and elastic rubber, which is mixed with certain fillers. O Additional substances are added to the eraser to improve the quality of erasure. For example, a mandatory additive is a plasticizer, which provides the quality of erasure.

Synthetic erasers can be of various shapes and colors, often with bright images.