Packaging and wrapping are an essential part of many different industries and even homes. We all occasionally wrap food items like sandwiches, utensils, etc while going out. In industries, we commonly create custom packaging for quick-to-spoil and easy-to-damage products like food items, juice, etc. One of the greatest inventions in the field of packaging is the aluminum foil. This amazing little thing, although feels unimportant, in reality, has revolutionized many industries.
So, let’s talk a bit more about it.
History of the Aluminum Foil
What we know today as aluminum foil was not the original iteration of the concept. Meaning that before aluminum, there was some other metal used to make this product. In the late 19th century, was the introduction of the Tin Foil. Yes, as the name suggests, these are made from compressing tin till it becomes a thin sheet, merely a few micrometers thick.
Contrary to popular belief, tin foils weren’t just used for wrapping food back then. It had multiple applications like insulating electronic components, it was used by dentists as a filling cement for teeth, etc.
Around a little over a decade after the advent of tin foil, a Swiss industrialist by the name of Heinrich Alfred Gautschi developed the prototype for the Aluminum Foil. Then in the year 1910, three men by the names – Dr. Lauber, Dr. Neher, and Dr. Cie opened the first aluminum foil rolling plant in Emmishofen. This led to the replacement of tin foils with aluminum throughout the market.
How are Aluminum Foils Made?
First of all, let’s debunk the misnomer, these foils are not purely made from aluminum. This is because refined aluminum is a very soft metal. It is one of the most malleable and the sixth most ductile metal in the world. These material properties make aluminum very prone to puncturing and provide its structural strength.
The process of making aluminum foils starts with melting aluminum together with iron and silicon in a furnace. The composition of the individual elements in the mixture is 98.5% Aluminum and the rest 1.5% iron and silicon. The materials are heated at 750 °C till they reach the fusing point and mix. A small sample of the mixture is poured out and tested to assess the quality of the mixture.
Then, the mixture is transferred from the furnace into a cool casting device that cools down the mixture and forms ingots of this allow. Now comes the time for rolling, but before that, they are heat treated (annealing), which improves the softness of the alloy. Then the ingots are put in the roller apparatus. This apparatus consists of a series of rollers that compresses the ingot thinner and thinner with each passing. Sometimes the alloy is heat treated in the middle of rolling. This process is done till the ingots reach the desirable thickness level.
The last station at the rolling apparatus consists of two rollers with polished steel surfaces. In this station, two sheets are inserted together. The side of the sheets facing the rollers become shiny and the sides touching each other remain dull. The final product is then cut and rolled into the product size and packaged properly.
Applications of Aluminum Foil
Nowadays, there is seldom anyone who doesn’t have an aluminum foil roll in their kitchen. These little products have become a part of our day-to-day ventures and have proven to have vast applications.
(A). Food Packaging
As an Indian, I'm sure almost every one of you has had rotis wrapped in aluminum foil for your school lunch. One of the most popular uses for aluminum foils throughout the years has been wrapping and packing food. Whether it is for home use, i.e., packing tiffins, lunches, etc. Or for commercial uses, like your favorite chocolate packaging. Fun fact, one of the biggest reasons why these foils became so common to use, was due to the chocolate brand Toblerone. This was the first food brand that used aluminum foils in packaging their famous triangular chocolates.
The biggest benefit of using these foils for packing food is aluminum’s low density, making it a bad conductor of heat, helping keep food warm for longer periods. Another benefit is that aluminum is not toxic and does not contaminate food items.
Another industry where these products are very popular is the pharmaceutical industry. Ever seen a packet of medicine? The backing layer that we rip off to take out the tablets is made of you guessed right, aluminum foil. These industries use aluminum, because it’s light (reducing the weight of the packaging), easy to open but still provides protection, and it protects the medicines from the outside environment.
(C). Wine Bottles
You may have seen in movies, that people always break out the corks from a wine bottle, and wonder why do wine bottles not use normal caps. That is because, wines are primarily consumed for their taste, and any foreign material, even metals coming in contact with the wine can change its flavor.
However, nowadays, many vineyards have shifted from corks to aluminum caps for their bottles. As aluminum has been shown to not interact with the beverage and provide a better seal than corks.
(D). Doy Packs
Lastly, doy packs, but what are doy packs? Have you ever seen beverages like Paperboat? Or packets for facemasks, dried berries, organic food, etc? Until 10 – 12 years ago, such packaging was rare, now they almost dominate the market of mid to high-end products. These are known as Doy Packs, named after their inventor, a Frenchmen named Louis Doyen.
These packages are made primarily of aluminum foil, and they are very famous for one particular reason. That is weight, before doy packs, manufacturers, especially manufacturers of beverages used glass bottles. The problem with glass bottles is that they add a lot of weight to the final product. This increases the transportation space and cost needed to provide the product to the consumer.
With the advent of doy packs, these costs went down severely, as glass bottles on average weigh about 400% to 500% of the liquid inside. While Doy packs only weigh about 6.1% of the total product weight.
Benefits of Foils Over Alternative Means of Wrapping
Now you know the history, manufacturing, and uses of aluminum foils in our daily lives. However, there is one more question that comes to mind. Why is aluminum foil so popular? Why, even after a century, do this simple product still dominate all the other type of wrapping and packaging materials?
To answer this question, let’s discuss the advantages that foil has over its alternatives.
When it comes to manufacturing and selling consumer items, one of the biggest issues that businesses face is the cost of transportation. A big aspect of this issue is the weight of packaging, as multiple layers of dense materials required to protect the product from the environment also increase the weight of the product. Meaning less capacity per transport, meaning more trips, meaning more fuel, cost & pollution.
Being a very light material and one of the least dense metals, aluminum solves this problem quickly. As mentioned above, the weight difference between doy packs and glass bottles, the weight difference is around 693.9% to 493.9%.
(B). Temperature Insulation
Although aluminum is a metal, with 3 valent/free electrons in its outer shell, making it a very good conductor of electricity and heat. However, its lack of density more than makes up for it by providing it with amazing insulator properties. In terms of packing, this allows aluminum foils to preserve the heat in the product it is wrapped around.
(C). Safety & Non-Reactant
These foils are good for wrapping out food items as they do not react with the items, thus, there is no risk of contamination or changing flavor.
(D). Flexibility & Versatility
Foils are extremely flexible due to their thinness, and aluminum’s ability to be extremely malleable. Meaning, that these foils can easily be wrapped or crumped around an object without the fear of tearing or breaking. This also provides aluminum foils with extremely versatile potential applications.
Other packaging/wrapping alternatives like Saran wraps are not biodegradable, cardboard s difficult to recycle, etc. Aluminum foils don’t pose a threat to the environment & are extremely easy to recycle. According to industry statistics, recycling a foil only takes about 5% of the total energy required to make new foil of the same quantity.
(F). Cost Reduction
Lastly, the biggest advantage from both a consumer & business point of view, is that aluminum is extremely cheap to manufacture and purchase. Meaning that it can be incorporated into different applications, without any significant increase in cost.
Frequently Asked Questions
Q1. What's in aluminum foil?
It is a roll of a continuous thin sheet of aluminum, a metal. These foils are used both in our personal lives at home and in various industries.
Q2. How is aluminum foil made?
It is made by first creating an allow of aluminum with iron and silicon. Which is then treated and rolled into thin sheets. To learn about this subject in depth, read the blog above.
Q3. What is the use of aluminum foil in laboratory?
Labs regularly employ the use of aluminum foils, in applications like – sealing bottles & tubes, securing cultures, insulating corks, etc.
- Last updated on Sep 02, 2023