Choose language:
» Personal Loan No Credit Check, Online Economics » Office materials » Topics begins with E » Eraser
An eraser is a particularly prepared rubber, with which with a pencil or with ink provided lines are removed from a carrier medium (mostly paper). It is differentiated between india rubber and Kunststoffradierern.
Kautschukradierer consist of the milk (Latex) of the india rubber tree (Hevea brasiliensis) and Faktis, of carrot oil manufactured white-yellow measures. After addition of sulfur the mixture under pressure on approximately 150 degrees of Celcius is heated up. The kneadable Kautschukmasse mutates with this procedure (vulcanize) to a flexible material. Around its abrasion quartz powder and other fillers will strengthen such as chalk as well as coloring materials of the rubber mass added.
Kunststoffradierer consist usually of Polyvinychlorid (PVC), which becomes flexible by additive of softeners.
The graphite particles transferred by the pencil to the paper cling there by the adhesive power. Since the india rubber of the eraser has a higher adhesive power than paper, it pulls during the mechanical abrasion (lat. radere: scratch, scrape) the graphite away from the paper. For optimal erasure results the eraser must be led diagonally to the line. With parallel to the line led eraser smudges often arise.
With ink and other pins only the paper becomes finely angerieben by erasing.
In the year 1770 the Britisher discovered Edward Nairne that india rubber is suitable for removing from pencil lines. The British natural scientist Joseph Priestley made this discovery public after an observation in the same year and was therefore considered long time as the inventors of the eraser. Already in the middle 16. Century is to have been fulfilled with bread the same function.
We found here 6 related websites.
Index | Privacy | Terms Of Use | Sitemap | Feedback
Printer Friendly Format
Bookmark this page
Back to "Office materials"
Back to top