In the early days, the tin foil was used for food packaging. But the tin foil was harder than that of aluminum foil, and the smell of tin would remain in food. In addition, tinfoil had a lower melting point and was not suitable for grilling or baking food, which limited its application in food packaging. After World War II, new production technologies enabled aluminum foil to be mass-produced cheaply and with a durable texture. Aluminum foil for food packaging gradually replaced tin foil in daily life.
Aluminum foil is produced by rolling aluminum metal. The thickness range used in food packaging is 0.006-0.3mm. At the end of the 19th century and the beginning of the 20th century, the European aluminum industry developed rapidly, and handmade aluminum foil appeared. Aluminum foil was officially produced in Germany in 1911 using the rolling method.
Food packaging is the most common application field of aluminum foil. It is a soft metal film that has the advantages of moisture-proof and corrosion-resistant, air-tight and light-shielding, fragrance-preserving, non-toxic and tasteless.
Packaging butter in aluminum foil can extend the shelf life of butter by 2-3 months compared to tin foil. The thickness of aluminum foil in general food packaging bags is only 6.5 microns. The thin aluminum layer is already waterproof, maintains the fresh taste of food, and is anti-bacterial.
Aluminum foil is widely used for aviation food packaging, ordinary meat packaging, pharmaceutical packaging, chocolate packaging, etc. Aluminum foil also has the advantages of being easy to bend and has good printing and decorative effects, making it very popular among food merchants. Take chocolate packaging as an example. Common shapes include square, bar, circle, diamond, oval, heart-shaped, cute animals, etc. Such ever-changing shape designs were unimaginable before alu foil packaging.
In addition to food, another application area that cannot be ignored is pharmaceutical packaging, which is mainly reflected in blister packaging, which is currently the most important packaging method for pills. The thickness of medicinal aluminum foil is generally 0.02 mm. It has the advantages of non-toxic, corrosion-resistant, impermeable, heat-resistant, moisture-proof, light-blocking, high-temperature sterilizable,etc.