Materials
No cans currently in wide use are composed primarily or wholly of tin; that term rather reflects the nearly exclusive use in cans, until the second half of the 20th century, of tinplate steel, which combined the physical strength and relatively low price of steel with the corrosion resistance of tin.
Use of aluminium in cans began in 1957. Aluminium is less costly than tin-plated steel but offers the same resistance to corrosion in addition to greater malleability, resulting in ease of manufacture; this gave rise to the two-piece can, where all but the top of the can is simply stamped out of a single piece of aluminium, rather than laboriously constructed from two pieces of steel. Often the top is tin-plated steel and the rest of the can aluminium.
A can usually has a printed paper or plastic label glued to the outside of the curved surface, indicating its contents. Some labels contain additional information, such as recipes, on the reverse side. A label can also be printed directly onto the metal.
In modern times, the majority of food cans in the UK have been lined with a plastic coating containing bisphenol A (BPA). The leaching of BPA into the can's contents is currently (as of early 2010) being investigated as a potential health hazard.
Read more about this topic: Tin Can
Famous quotes containing the word materials:
“Realism to be effective must be a matter of selection. ... genius chooses its materials with a view to their beauty and effectiveness; mere talent copies what it thinks is nature, only to find it has been deceived by the external grossness of things.”
—Julia Marlowe (1866–1950)
“Young children learn in a different manner from that of older children and adults, yet we can teach them many things if we adapt our materials and mode of instruction to their level of ability. But we miseducate young children when we assume that their learning abilities are comparable to those of older children and that they can be taught with materials and with the same instructional procedures appropriate to school-age children.”
—David Elkind (20th century)
“Kicking his mother until she let go of his soul
Has given his a healthy appetite: clearly, her role
In the New Order must be
To supply and deliver his raw materials free;”
—W.H. (Wystan Hugh)