The origin of aluminum foil can be traced by to the early 1900s. Life Savers—one of today’s most popular candies—were first packaged in foil in 1913. To this day, the treats are encased in the world-famous aluminum foil tube. The uses of foil have grown over the past 100 years to a nearly endless count. From Christmas tree ornaments to spacecraft insulation, TV dinners to medicine packets—aluminum foil has, in many ways, improved both our products and our lives.
Aluminum foil is produced by rolling sheet ingots cast from molten billet aluminum, then re-rolling the sheets to the desired thickness. To maintain a constant thickness, beta radiation is passed through the foil. Sensors on the far side sense the radiation levels and adjust the rollers to apply more or less pressure. Foil can also be produced by continuously casting and cold rolling. Aluminum foil provides a complete barrier to light, oxygen, moisture and bacteria. For this reason, foil is used extensively in food and pharmaceutical packaging. It is also used to make aseptic packaging that enables storage of perishable goods without refrigeration.
The first pre-formed, all-foil food packaging containers appeared on the market in 1948. This grew into the complete line of die-formed and air-formed foil containers now sold in every supermarket. A spectacular period of growth occurred in the 1950s and 1960s. TV dinners, packed in compartmental trays, began to reshape the food products market. Packaging foil is now divided into three major categories: household/institutional foil, semi-rigid foil containers and flexible packaging. For decades, the use of foil has grown steadily in each of these categories.
Increasingly, aluminum foil is being merged with flexible films to create lightweight packages. This technology allows the packages to expand during production, then contract as the product is consumed. The packaging of pet food, tuna, coffee and soups alone produces 13 billion packages that are candidates for replacement with flexible foil-based packages.
The earliest production of aluminum foil occurred in France in 1903. In 1911, Bern, Switzerland–based Tobler began wrapping its chocolate bars in foil. Their unique triangular bar, Toblerone, is still widely available today. Production of aluminum foil in the United States started in 1913. The first commercial use: packaging Life Savers into their now world-famous shiny metal tube. The demand for aluminum foil skyrocketed during World War II. Early military applications included the use of foil strips, dropped from bombers, to confuse and misguide radar tracking systems. Aluminum foil was so vital to the defense effort that families were encouraged to save strips of foil. In many towns, the collected foil balls could be exchanged for free entry to a movie theater. One of the most innovative uses of aluminum foil came in the early 1960s. The aluminum Christmas tree debuted—complete with foil-covered branches and decorations.
Aluminum foil has a shiny side and a matte side. The shiny side is produced when the aluminum is rolled during the final pass. It is difficult to produce rollers with a gap fine enough to roll a single sheet of foil. For the final pass, two sheets are rolled at the same time, doubling the thickness of the roll. When the sheets are later separated, the two inside surfaces are matte, and the two outside surfaces are shiny.