A perforation is a
hole made by puncturing a surface. However, the term frequently refers to the practice of creating a long series of holes so that
paper can be torn more easily.
Postage stamps are one common application of this, where small round holes are cut in lines to create individual pieces (see
postage stamp separation). Since the creation of perforation devices in the
1840s and
1850s, it has seen use in several areas. It is common for
notebooks and
legal pads to have perforations making it easier to tear out individual pages. Perforations on stamps are rather large, on the order of a
millimeter, in comparison with other perforated materials often have smaller holes.
Film stock is perforated to allow it to be moved precise distances at a time continuously.
Screwcaps on glass or plastic bottles are sealed with a ring at the bottom of the cap attached by perforation. Twisting the cap has the effect of rupturing the perforation and indicating that the original seal has been broken.
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Als Perforation (auch Perforierung, vom lat. foramen =
Loch) bezeichnet man eine Durchlochung von Hohlkörpern oder flachen Gegenständen. Regelmäßige Anordnung, Menge, Form und Größe der Löcher spielen besonders in der Technik eine Rolle.
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PERFORAMENTO. PERFORAZIONE. TRAFORO. DENTELLATURA
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