Abrasives and films

It is believed that the first sandpaper or sandpaper (although the word "emery", so firmly entrenched in everyday life, denotes a very specific geological rock that was used for abrasive processing and was mined in Turkey) was invented and widely used in China from 13 oh century. It consisted of sand, finely crushed shells or seeds of certain plants, pasted with a paste on parchment. Also used as a sanding skin, for example, the skin of sharks. Much later, a fully synthetic analogue of sandpaper appeared, which used crushed glass as an abrasive, the so-called. "sandpaper". Serial production of "glass" paper has been organized in London since 1833 by the company of entrepreneur John Okay (John Oakay), and the first patent for the production of sandpaper was issued to Isaac Fischer the Younger (Isaac Fischer) on June 14, 1834 in Springfield, Vermont. The mass production of sandpaper and glass paper only began in 1900 by Siegener Leimfabrik & Naxos-Schmirgelwerke. Later, the 3M Company (in 1916) and the Klingspor Company (in 1925) applied for a patent for the invention of waterproof sanding paper. At the same time, the sheet size of 230 * 280 mm was fixed as a standard size.