Over 100 years old and still moving forward
*Info from The European Aluminium Foil Association e.V. (EAFA)*
A little overview about alufoil’s history looking at past, current and some future (technical) developments.
Conceived as a replacement for tin foil, Robert Victor Neher took out a patent in 1910 for the continuous rolling process and opened the first aluminium rolling plant in Kreuzlingen, Switzerland, and by 1911 Bern-based Tobler began wrapping its chocolate bars in alufoil including the unique triangular chocolate bar, Toblerone. And by 1912 alufoil was being used by Maggi to pack soups and stock cubes.
Over its history converters, brand owners, retailers and ultimate consumers have all benefited from alufoil's unique barrier properties which provide a total block to light, moisture and aroma. Today it is used in every conceivable market from food and drink to pharmaceuticals. Applications include aseptic beverage cartons, sachets, pouches, lids, wrappers, blister and strip packs, foil containers and much more. And coming up over the horizon are even more markets and resource efficient options. These include microwaveable containers gaining a foothold throughout Europe and fascinating and technically innovative applications for pharmaceutical foils.
But none of this would have been possible without the vision of the early innovators. In the 1920's for example the dairy sector began to benefit from alufoil's advantages over the previously used tin foil: its chemical properties meant that it did not turn black when coming into contact with cheese and was some 20 % more economical than using tin. Other uses included baking products where alufoil's non-stick properties came into their own, while by the mid-1930's the European alufoil sector began to produce rolls of household foil for the domestic kitchen as either a tear off product on rolls or as loose sheets in bags. Marketed as "sterile, free from bacteria, clean and trouble free, and reusable" alufoil's inroads into packaging markets continued up to the Second World War.
A spectacular period of growth in the 1950's and 1960's saw alufoil production quadruple, and both rolling speeds and rolling widths increasing dramatically, helping to feed demand. In the early 1950's as freezers became more affordable and began to appear in consumers' homes, TV Dinners, the forerunner of today's ready meals, packed in compartment alufoil trays began to shake up the food market. Developments such as these signposted the beginnings of a revolution in consumer convenience with alufoil used successfully for frozen foods, soup and stock cubes; and heat-sealable pouches for coffee, cocoa, tea and spices.
The 1960's heralded a number of major market developments where alufoil's protective properties against light and oxygen were used to good effect, for example thin alufoil was used in conjunction with paper and PE to create a laminate for aseptic cartons (Tetra Brik). And in 1978 the first use of an aluminium-plastic laminate took place for a well-known effervescent tablet for headaches. By the end of the 1990's alufoil was accepted as an innovative material for almost all packaging applications with expressions such as "foil-sealed for freshness" becoming commonplace on many branded packs.
Come the new millennium resource efficiency and even better consumer convenient options were the major goals for alufoil, as they were for all material sectors, converters, brand owners, retailers and consumers. Successes in lightweighting led to material savings of more than 30 % in the 2000's, and in turn this has provided growth in markets for resource efficient packaging options, where its recyclability is also a major plus for customers and consumers alike.
Today alufoil's unique barrier properties are being merged increasingly with flexible films to create lightweight packs with excellent preservation properties and this has been instrumental in their use for a number of exciting new and expanding markets including pouches for everything from pet food to drinks; lidding applications; technically innovative solutions for pharmaceuticals; and the increasing acceptance of alufoil as a microwave safe material.
The manufacture of aluminiumfoil dates back to the beginning of the 20th century. Prior to 1900 small quantities of aluminium foil had been produced by hammering, a laborious and costly process, it wasn't until 1908 that the production of aluminium sheet in thicknesses down to 0.05 mm really began with so-called pack rolling, based on a patent taken out by Swiss entrepreneur Alfred Gautschi in 1908.
The process involved cutting athin sheet of alufoil into pieces placing one on top of the other andre-rolling several times.
But it wasn't until 1910 that the process began to make giant strides when Robert Victor Neher and hispartner Dr Edwin Lauber patented a method to produce strip and foil continuously using automatic coiling in a similar way to that used for tin.They produced usable aluminium foil strip in quantities of about 200 kilograms/month in thicknesses of 0.03 - 0.04 mm.
Alufoil quickly found an application for chocolate wraps and by the middle of the decade coloured,embossed and printed aluminium foil was being produced.
Between 1910 and 1920 a series of process-related problems associated with aluminium foil manufacturing were solved including slitting using rotary shears instead of a band saw, annealing of the ready-cut coils of foil, and grinding of the rolling rolls.
One of the pioneers of modern aluminium foil technology was Rheinische Blattmetall (Rebag) based in Grevenbroich, Germany. Founded in 1922 Rebag established methods capable of rolling aluminium foil 320 mm wide at speeds of 12-24 metres/minute with an average thickness of 0.012 mm.
After the end of the Second World War, productivity increased to a rolling width of 510 mm and rollingspeeds of 80-90 metres/minute.
During the 1950's and 1960's, foil production underwent dynamic growth, with new investment in technology leading to the development of two-high, then three-high and subsequently four-high rolling mills playing a significant role. This resulted in further improvements to auxiliary machinery and special equipment such as coilers and straighteners, exit devices, strip and slitting shears, coil transport units and ingot saws. By the second half of the 1950's, rolling widths of 1,100 mm and speeds of 500 metres/minute were reached.
Aluminium foil's triumphantmarch as a barrier material in flexible packaging began in 1963 when thicknesses of less than 0.009 mm became possible. The rolling mills used high-purity steels for the rollers, which avoided the formation of rollingholes, while it also became possible to reduce successively rolling oilviscosity, thus increasing rolling speeds still further and also improving the annealing quality. At the end of the 1960's, it was possible to produce thin foilsof 0.0065 mm, similar in thickness to the foils used today for asepticpackaging of liquids.
At the beginning of the 1970's, the first rolling line with integrated transport and high bay warehousetechnology for strip and coils was commissioned. And by the mid-1970's, rollingspeeds reached 1,500 metres/minute and the rolling width rose to 1,500 mm. Rollroughness is increased step-by-step and electroslag-refined roll materials are used. (The electroslag process is used for remelting and refining steels and special alloys to create high-purity product.)
During this period, a stripthickness control with fully hydraulic adjustment was incorporated into a rollstand for the first time. It replaced the electro-mechanical adjustment that was used previously and allowed a high degree of dynamic control based on roll-gap measurement.
Significant developments in rolling-mill technology were made during the 1980's with improvements to process-engineering, drive technology, and control and instrumentation. Ever greater rolling speeds led to a considerable increase in the requirements for stripflatness and strip thickness necessitating fully automatic measurement, display and control of the strip flatness. In 1987, the rolling speed of new units reached 2,200 metres/minute and a rolling width of 1,800 mm; alufoil for flexible packaging was rolled down to a thickness of 0.00635 mm.
In the 1990's, the emphasis is on the optimisation and automation of the complete foil-rollingplant. This included plant optimisation to provide environmental protection(exhaust air purification) and occupational health and safety. Today, foil-rolling plants with rolling widths of up to 2,150 mm are commercially available and can produce aluminium foil as thin as 0.006mm at rolling speeds of 2,500 metres/minute.
From chocolate wrapping to packaging allrounder
Robert Victor Neher who applied for a patent for the continuous rolling process and opened the first aluminium rolling plant in 1910 at Kreuzlingen, Switzerland, could be called the father of alufoil production in Europe. Destined to replace tin, among the major advantages demonstrated by aluminium foil in comparison with tin were its lightweight and its cheaper production costs.
In 1912 Neher, with his partner Dr Edwin Lauber, created a limited partnership Dr. Lauber, Neher Cie, and formed the German subsidiary Aluminium-Walzwerke Singen GmbH under the holding company Aluminium-Walzwerke AG. The Singen business later became part of the global Alcan business and today is Amcor Flexibles Singen.
In that era, a local press report said: "The aluminium rolling mill commissioned here a few months ago is blossoming quickly and already working day and night shifts in order to satisfy the demand for aluminium foil. Produced in a variety of thicknesses, it is replacing the customary silver foil as a wrapping for chocolate and other consumer goods."
Importantly Neher and Lauber were also able to successfully assist prospective users of alufoil by creating the necessary new systems for packaging and converting equipment.
However credit must also be given to Martin Kiliani, Aluminium-Industrie, who in 1890 forecasted that an aluminium sheet was better than tin foil for chocolate packaging and the vision of his remarks can be judged by the almost instant success of alufoil as a packaging material due to its barrier and aroma protection properties; something which is still in evidence today. Both the forward-thinking Neher and Kiliani were instrumental in the first use of alufoil to wrap chocolate, which took place in 1911 when Bern-based Tobler began wrapping its chocolate bars in the material. This included the unique triangular chocolate bar, Toblerone which had been launched in 1908. And by 1912 alufoil was being used by Maggi to pack soups and stock cubes.
In the 1920's alufoil's influence as a successful packaging material in Germany grew sufficiently to make real inroads into the dairy sector, one of the largest sectors of the German economy, and during the 1920's and 1930's alufoil comprehensively conquered the packaging market for butter and cheese. At the time a reviewer of the sector wrote: "More so than in any other sector, foil keeps highly sensitive products, especially butter and cheese fresh longer. It is an unrivalled and indispensable aid in the battle against deterioration."
And in 1937 alufoil was first proposed as a packaging material for butter at the World's Dairy Congress in Berlin. Results of studies revealed that alufoil allowed butter to stay fresher for two-three months longer than previously used materials. And as one speaker correctly forecast, "The favourable properties of alufoil mean it will become the simplest and cheapest form of ‘keep-fresh' packaging in every household."
Alufoil had a number of other advantages compared with the previously used tin foil: its chemical properties meant that it did not turn black when coming into contact with cheese and was some 20 % more economical than using tin. Other possible uses were also explored for example baking products where alufoil's non-stick properties came into their own. Marketed as "sterile, free from bacteria, clean and trouble free, and reusable" the inroads into packaging markets for alufoil, sometimes called silver paper or silver foil, continued up to the start of the Second World War.
In the mid-1930s the European alufoil sector began to produce rolls of household foil for the domestic kitchen as either a tear off product on rolls or as loose sheets in bags. Household foil had been introduced successfully in the US some years earlier in the late 1920's.
Other suggestions for use, some of which are alive and well today, included Easter Eggs; soap; a layer under postage stamps to prevent sticking; decoration on serving dishes; and even as a scarecrow with the alufoil continuously sparkling in the wind.
(1945 - 1999)
Technical advances conquer new markets
After the Second World War alufoil began a spectacular period of growth with worldwide alufoil production quadrupling to 280,000 tonnes between 1950 and 1960. At the same time both rolling speeds and rolling widths increased dramatically, helping to meet the high demand for converted products.
A series of landmark technicaldevelopments signalled remarkable success in packaging markets. For instance inEurope the first alufoil food containers were used for bakery products appearing on the market in 1948, soon followed by a variety of other foodstuffs.
European and North Americanmarkets were increasingly catching on to alufoil benefits as an efficientpackaging material but, although by this time the industry it is nearly five decades old, the technology of rolling, processing and conversion is still based mainly on practical experience not on solid scientific foundations.
The need forscientifically-based research is accepted and in co-operation with associatedfood technology institutes, intensive investigations began into the deformation of alufoil, the strength of heat-sealed seams and the vapour impermeability of packaging. Investigations also extended to composites and laminates made up of different materials including alufoil and paper, and/or plastic or cellulosefilm.
Thanks to these advancesalufoil with its total barrier to light, moisture, and penetration of aroma andflavour, was now in use for perishable products throughout Europe. Alufoil's aesthetic attributes were not forgotten and its bright metallic or matt finish plus its compatibility with printing technologies were beginning to be used to good effect.
Markets in which alufoil wasgaining increasing acceptance in the 1950's included thin neck foil for winesand beers where its decorative potential was used to marketing advantage; and lidded semi-rigid foil trays, lacquered where necessary to protect against acid, which could be filled on conventional filling and packaging equipment.
The early 1950's saw freezersbecoming more affordable and as they began to appear in consumers' homes the TVDinner, the forerunner of today's ready meal, was created in the US in 1954. Packed in compartmented aluminium trays the idea soon spread to Europe.
Developments such as thesesignposted the beginnings of a revolution in consumer convenience with alufoilused successfully for frozen foods, soup and stock cubes; and even heat-sealable pouches for coffee, cocoa, tea and spices.
But it was not only consumerpackaging that benefited, by the 1950's semi-rigid alufoil was also in use fortechnical applications such as industrial products including fats, waxes and adhesive compounds. In the building and construction industry alufoil was being used as thermal insulation and as moisture-proofing for applications including roofs.
The 1960's heralded a number of major new market developments where alufoil's protective properties against light and oxygen were used to good effect. For example thin alufoil was used in conjunction with paper and PE to create a laminate for aseptic cartons (TetraBrik). Originally conceived for use with UHT milk, the alufoil laminated carton has now established itself for applications including fruit juices, soups, yoghurt drinks and much more. Additionally thanks to its heat and moistureresistance alufoil started to be used to pack foodstuffs to be sterilised in autoclaves. And by the 1960's household foil was becoming increasingly accepted across the majority of European markets.
Another success story in the 1960's was the alufoil laminate tube, comprising plastic/paper/ alufoil, which conquered markets for goods such as toothpaste, cosmetic creams and pharmaceutical ointments.
Aluminium laminates were used increasingly for pharmaceutical products during the 1970's, where the resistance to water vapour and gas tight properties were used to good effect. In 1978 the first large-scale use of an aluminium-plastic laminate, for a well-known effervescent tablet for headaches, took place. And by the 1980's blister packs were starting to be introduced on a wide scale.
Indeed by the end of the 1990's alufoil was accepted as an innovative material for almost all packagingapplications with expressions such as "foil-sealed for freshness" becoming commonplace on branded packs. Alufoil was also responsible for the growth of a new market for easy-open ‘gourmet' pet food containers.
It was the barrier properties of alufoil which were instrumental in its success up to the end of the 20th Century and this continues today. Setting it apart from other materials are it's total block to light, moisture and aromas with a very thin layer of alufoil transforming the performance of a flexible packaging laminate.
Greatly assisting the growth of alufoil was the formation of the European Aluminium Foil Association in 1974 which has been instrumental in spreading the message to a wide audience, and growing its success into the 21st century.
The new millennium
The age of convenience and resource efficiency
Come 2000 resource efficiency and even better consumer convenient options were the major goals for alufoil, as they were for all material sectors, converters, brand owners, retailers and ultimate consumers.
Successes in lightweighting of alufoil which had begun in the eighties led to material savings of more than 30% in the new millennium, and in turn this has provided growth in markets for resource efficient packaging options. Today alufoil's unique barrier properties are being merged increasingly with flexible films to create lightweight packs with excellent preservation properties and this has been instrumental in the iruse for a number of exciting new and expanding markets. To name just a few, pouches for everything from pet food to drinks; lidding applications; technically innovative solutions for pharmaceuticals; and the increasing acceptance of alufoil as a microwave safe material.
FOOD & DRINK
Combined with plastic films of numerous specifications - which have also developed rapidly over recent years -alufoil has enabled foods and other products to enjoy greatly extended shelflife. In contrast to three decades ago, when the steel can ruled, today autoclaving and aseptic filling of lightweight flexible packs routinely ensure that food and products are sterile and remain in top nutritional and tasteconditions for many months.
Alufoil's characteristics have given it the role of ‘enabler' in several innovative applications. For example, high barrier foil laminates have transformed the vacuum packaging of coffee,once the exclusive domain of tinplate cans.
HEALTH & BEAUTY
Convenient, safe and versatile alufoil packaging offers formats for tablets, creams, liquids and powders, covering an enormous variety of pharmaceutical and cosmetic products. Today alufoil's unrivalled barrier properties are being used increasingly for products that need to totally exclude moisture, oxygen and other gases, micro-organisms and light.
Alufoil is particularly suitable for blister packs due to its range of mechanical properties, and depending on the alloy and treatments alufoil can be made more brittle, tougheror more ductile. It can also be combined with other materials to create a range of innovative solutions including, for example, tamper-evident and childresistant blister packs.
Deep drawn alufoil containers with smooth shoulder rims have created a growing demand for prepared meals as well as meat joints and fish dishes. Advances have included intelligent design that produces not only reported lightweighting and material savings of up to 30%, but also provides add on advantages thanks to advances in alloy and designtechnology to give strong and stable shapes including contoured handles to help consumers grip when hot.
Additionally consumerattractive lightweight ribbed trays using innovative have brought the alufoiltray to the fore for applications such as ready to cook meat, poultry, and fish, roast potatoes, barbecue meats with marinades, and roast summer and winter vegetables.
All these strong and stabletrays have the aesthetic appearance of a ‘standard' alufoil container with no acute-angled corners; and a smooth flange area to provide good heat-seal integrity.
The objective is always to save time in the kitchen without compromising quality. For example small meat and poultry cuts are presented in the ready-to-cook ribbed tray, hermetically sealed and protected with an inert gas to reduce oxidation and to extend shelflife. The consumer need not touch the raw meat or fish and the dish acts as an effective, heat-conductive, cooking vessel which has secondary uses and is readily recyclable.
Alufoil's attributes as a microwave safe material was one of the most significant advances of the new millennium.
*Info from The European Aluminium Foil Association e.V. (EAFA)*