Aluminium Foil Markets
*Info from The European Aluminium Foil Association e.V. (EAFA)*
It is inconceivable today to consider packaging materials without acknowledging the primary role of aluminium foil in the marketplace. Likewise for technical applications the properties of aluminium foil are vital to the effective performance of many important components in transportation, construction and interior design.
Alufoil’s versatility is remarkable, making it an ideal material for many forms of packaging, across all product ranges, but particularly food. Its strength, malleability, formability, barrier properties, deadfold characteristics and the ability to stand extremes of heat and cold are unique amongst packaging materials. Foil’s decorative qualities, and the fact it can be printed on, lacquered, embossed and laminatedwith other materials means it is the most multi-faceted and ubiquitous materialavailable.
For technical applications it adds lightness, reflective ability, conductivity and robustness to the properties listed above. This has helped to revolutionize some ‘under the bonnet’transport components, combining safety as well as comfort to users. In construction its strength to weight ratio and insulation features helps save resources and speed-up the whole building process.
Add to this the fact that aluminium foil saves more resources than are consumed in its production, through the complete value and supply chain, it can truly claim to be the perfect material for many applications:
Bakery and other oven-cooked products
"Sales appeal combined with production efficiency"
Consumers can rely on the dependability and versatility of alufoil foodcontainers. They combine all the features needed to deliver the consumer fresh, wholesome and quickly accessed baked products to satisfy their demand for quality and value.
Bright and reflective, alufoil containers stay in perfect condition throughout processing and marketing. They can be embossed, colour lacquered or printed with brand identity and colours both inside and out.
Alufoil containers withstand the extremes of all types of cooking: grilling, fan and convection oven, barbecue griddle and microwave oven as well as re heating. They are easy to handle, easy to open, easy to use and to dispose of.
Adding even more versatility is a range of purpose designed liddingmaterials – from straightforward foil/board laminates to more sophisticated coated or laminated alufoil lids that can be sealed to the container rim yet peel off easily.
Foil’s characteristics satisfy the many demands of chilled or frozen bakeryproducts. Thanks to its ready formability and robustness, aluminium foil can provide a large variety of standard shapes, sizes and smoothwall designs.
Oval, round, shallow or deep
Shapes and sizes are available for a huge range of products such as fruit flans, deep apple pies, individual steak and kidney pies or large multi-portion catering desserts.
Rectangular shapes for large items
For larger containers, extra strength can be designed into the walls. By incorporating corrugated sides, the rigidity of the container can be greatly enhanced. Also, there are folded containers specifically for baked products, such as cakes, that need to present an extra-smooth surface when removed from the dish.
Embossing
The intrinsic ‘deformation memory’ of alufoil provides an added opportunity for branding and information. An embossed recycling logo reminds the customer of the value of the used aluminium container – an environmental pack advantage that can be promoted by brand owners.
Lidding choices
The range of lidding options goes from simple fold down rigid foil/board closures to snap-on covers in foil or plastic. Hermetic sealing with transparent films or heat resistant foil membranes is possible with smoothwall trays that have smooth, horizontal rims.
Compartmented trays
Originally designed for ‘ready meals’, the compartmented alufoil tray has many other uses: a baked pastry or dessert using one compartment with a fruit sauce in the other is just one example.
Presentation trays
Rigid alufoil serving trays can be used as support for separate pastries and tarts. They are good looking, re-useable and the ultimate in convenience. Again the potential for embossing and decoration is available.
Smoothwall dishes
The smoothwall lends itself to the premium end of the market particularly if the outer surface is coloured or printed. Presentation quality can be greatly enhanced for prestige baked products.
Related uses
Alufoil containers are in widespread use for many other applications as their combination of properties offer great advantages. Heat processed dairy desserts, pâtés, prepared and oven-ready meat, poultry and fish, ready-to-cook frozen desserts are just some examples.
Drinks and Aluminium Closures
Thanks to its combination of properties, aluminium foil is used in a wide variety of beverage and other liquid packing applications:
Beverage cartons
It is not widely appreciated that virtually all liquid food products, such as milk, juices, soups and cream, that require long term unrefrigeratedprotection are packed in laminates containing a layer of alufoil. A 6 micron aluminium foil layer renders the lightweight pack totally impervious to light, taint and gases without compromising carton rigidity.
Such ‘long life’ cartons come in a variety of shapes and sizes. Packs are evolving all the time with easy-to-open and re-sealable closures as well as easy to hold formats with eye-catching designs.
A very important advantage is environmental performance. The ability to preserve products for long periods without refrigeration provides great energy savings. Their shape makes them very ‘space efficient’ in storage and display, producing big energy and cost savings. Added to this, foil lined liquid cartons are light– only 1.5g of aluminium in 28g of laminate for 1,000g of drink – yet provide reliable, long life protection. The use of alufoil enables enormous savings in terms of weight and resources compared with alternatives offering the same level of protection.
Pouch packs
Pouches are an increasingly popular option for drinks packaging; usually made from a multi-layer composite, of which alufoil is the essential barrierlayer. These packs, some of which are ‘stand-up’, have enormous visual impact and have been adopted for a wide range of sports and health drinks. Many of them incorporate tamper evidence features and closure systems that make consumption ‘on the move’ possible. Their very low weight-to-contents ratio saves resources.
Even though an empty 200ml pouch weighs less than a sheet of copier paper the pack is strong enough to meet tough drop and burst resistance tests, as well as providing the essential barrier properties . The remarkably lightweight of the pack enables considerable transport cost savings to be made. Additionally the packaging laminate is delivered in space saving reel form, so saving both storage and transport costs for the producer.
Bottle neck & capsule foils
Alufoil capsules or bottleneck labels add visual prestige to any type of bottle. They are a valuable part of the product’s personality and a guarantee of authenticity. Champagne and traditional bottled beers use them as a hallmark of product quality.
But the foil is not just there for decoration. It ensures security, providing tamper evidence in the case of ‘over the crown’ foil. Alufoil’s physicalproperties of ‘deadfold’ and malleability enable it to mould with the contours of bottles and closures in an easy-to-apply and brand building way. Opening a twist-off cap or crown closure is easily done without disturbing the appearance of the neck foil thanks to tear off perforation. The art and technology of bottle neck foils is moving ahead continually, resulting in material savings whilst retaining elegant appearance and high product security. Champagnecapsules are generally made from thicker gauge alufoil which is sometimes coated or laminated with a plastic layer. Alufoil has been adopted as the natural successor to lead as the material for spin-on capsules for winebottles. Neck foils are frequently embossed which, apart from giving a distinctive appearance, also makes the labels easy to handle. Other developments have also enabled smooth labels to be used. Labels with partialembossing adding an element of design appeal and individuality are a further option.
Aluminium Closures / Screw Caps
The practical and economic reasons for the popularity of aluminium closures or screw caps among producers and consumers are well established. They are secure, reliable and good-looking. Fully tamper-evident, an aluminium screw cap guarantees the integrity of the product whether carbonated or still.
It is the traditional closure for spirits, wine, spa water, soft drinks, concentrates and many other liquid products, including medicines. The reliability of screw caps is significant as even a small percentage of returns can mean serious loss of profit.
The acceptance of aluminium screw caps in the conservative wine closure sector is proof that it is a very efficient way to deliver high and consistent quality to the customer. Studies by wine producers and ‘blind’ tasting tests have shown that the screw cap brings a higher level of product consistency without detrimental effect to wine quality.
More information about aluminium closures can be found on the dedicated website www.aluminium-closures.org.
Foil labels
When it comes to creating a pack that reflects the luxury and quality of its contents alufoil labels can produce effects that enable brands to create a distinctive identity with maximum shelf impact. Alufoil’s naturally decorative surface can often be enhanced by high quality printing, embossing or even using the ‘matte’ side of the foil to achieve an antique metal effect. As alufoil is compatible with a wide choice of printing and finishing processes – offset, litho, gravure and flexo printing, punching, die cut shapes, laminating, lacquering, hot, cold and water-based adhesives and embossing – an alufoillaminated label offers an enormous range of options to designers.
Alufoil lid labels for beverage cans
Lid labels add an extra functional dimension to a beverage can such as informative display space, hygienic shield and a partly resealable closure. The lid label is an eye-catching tool for promotions, special events and relaunches and rounds off the impact made by the beverage can without changing the design of the can body. Thanks to aluminium foil's materialproperties the label adapts easily to the shape of the can.
Coffee, tea and chocolate drinks
Modern packaging has allowed sensitive products such as coffee to be enjoyed in many different ways rather than just freshly ground at the coffeehouse. Choices of method are now many: whether from a cafetière using ready ground beans, using‘pods’ or capsules in one of the modern machines, or in the cup using singleportion sachets of freeze-dried ‘instant’. With every method alufoil plays an important role.
For many years tea was mainly shipped in wooden ‘chests’ or boxes lined with aluminium foil for protection. Now aluminium foil plays a big part in retail packaging – bringing fresh, aromatic teas to the discerning public.
In addition other powdered or ‘instant’ drinks such as drinking chocolate are enjoyed in perfect condition despite a sometimes long storage period thanks to alufoil.
The availability of aluminium foil, which combines total barrier protection with flexibility, as well as attractive appearance and compatibility with other materials, is one of the keys to enabling consumer enjoyment of all types of coffees, teas and chocolate-based drinks.
Brand owners and retailers now offer coffees and teas for every occasion in both single-serve and family packs. In the workplace, in catering outlets and ‘on-the-move’ dispense points cover every moment. Preparation processes for instant coffees through to specialist varieties for cafetières, filter and espresso machines, plus single serve systems are adding to the multitude of consumer choices. This diversity, coupled with the need for product protection, has led to a large number of packaging alternatives featuring alufoil.
Stand-up pouches
This format combines lightness and high protection thanks to the alufoillayer. It can be used as an ‘eco-refill pack’ for instant coffee, as well as a regular presentation for ground coffee and for the pods used in coffeemachines. There are now easy-open and reclosable versions, adding convenience to full product protection. The latest ultrasonically welded valve systems are easily incorporated.
Fine printed effects combining reverse printing, which exploit the gloss of the outer film laminate with the luxurious metallic effect of the aluminiumfoil substrate, can be used to convey high levels of quality and appeal.
Vacuum and modified atmosphere packs
An established high-barrier format, this is used particularly for groundcoffee. Scientific study* has demonstrated that a vacuum pack laminate, which incorporates a layer of aluminium foil, achieves the best performance ins topping the loss of vital aromatic properties of coffee.
Foil lined cartons
Cylindrical alufoil/board cartons featuring a tabbed ‘pull-out’ alufoilmembrane will ensure total protection of tea. Reclosure, that can be provided by a plastic cap, will allow use over an extended period and can give the container a useful ‘second life’ as highly protective storage.
Single portion sachets
The alufoil sachet is a familiar packaging format, bringing instant one-cupconvenience to tea and coffee drinkers. The latest version – the ‘stick’ format– offers an easy-open system whether using laser scoring or slits in the outerfilm layer. A similar shape and convenience has been extended into the sachets used for instant chocolate and malt-based hot drinks.
Alufoil laminate sachets are also in widespread use for the protection of individual coffee pods and single-serve coffee filters.
Capsules
Domestic coffee making has reached new levels of sophistication with the growth in ‘home espresso’ systems. One uses an advanced combination of aluminium foil capsules (small smoothwall alufoil containers with alufoil lids)and machine technology with a unique extraction system. The attractive capsules are colour-coded according to coffee type – demonstrating creativity can be combined with excellence in performance.
The metal in the alufoil capsules is fully recyclable.
Alufoil ‘tea sticks’
This unique format uses the mechanical properties of aluminium foil to create a rigid perforated container for the tea. Alufoil’s ‘deadfold’characteristic, heat resistance and conductivity, food safety and compatibility with its contents and its decorative appearance are all combined. The alufoilStick Tea format also has the advantage that the tea can be removed cleanly from the individual glass or cup as soon as the desired strength has been reached.
*Verpackungs-Rundschau1/96 Technisch-Wissenschaftliche Beilage 48 (1996) No. 1 AROMA changes in coffee vacuum packed using different packaging materials: A. Lindner-Steinert,M. Zou; Fraunhofer-Institut für Lebensmitteltechnologie und Verpackung(Fraunhofer Institute for Food Technology and Packaging), Munich, Germany.
Dehydrated and dry foods
Drying as a technique for food preservation has a long history. It remains a very efficient and widely used way to greatly extend the life of foodstuffs. Once safely protected from light and gases, the food retains its nutritionalvalue and texture until re-hydrated.
Removing the water eliminates any support for bacteria and other contamination. It also removes a high proportion of the product weight and space requirements, saving valuable resources used in storage and transport.
Aluminium foil can provide the essential barrier needed to stop the ingress of moisture and escape of subtle flavours. It also prevents the UV rays, present in most forms of lighting, from causing ‘photo-oxidation’ and the rancid taste from fat and oil components in dried food products.
Alufoil, mainly in the form of sachets, is widely used to pack such fooditems as peas, beans, milk and soup powders, cake mixes, sweet and savourysauces, herbs and spices, yeast, instant beverages such as chocolate and malt-based drinks, tea and coffee. Single serve sachets ensure that the rest of the contents remain in top condition.
The sachet or pouch for driedproducts can be made in a variety of sizes and shapes, from the smallest ‘stickpack’ of instant coffee to very large multi-portion packs used by the cateringindustry for such products as soup and cake mixes.
Savoury sauces and soup powders, cheese and stock cubes
In the savoury foods sector there are usually sensitive but essential ingredients upon which the flavour and food value depend. Dry cheese products such as powdered Parmesan, require strictly controlled but low humidity content for long life coupled with good flavour. Meat, fish and poultry stock cubes, often high in moisture-loving salt, receive full (and deadfold) protection from a non-laminated alufoil wrapper.
Cake mixes, biscuits and sweet sauces
Many cake mixes, powdered dessert sauces and biscuits are high in sugar, a highly hygroscopic ingredient. The shelf life of biscuits can also suffer if not fully protected from oxygen and moisture. Alufoil laminated pouches and sachets can stop such deterioration.
Hot and cold beverages
Sold in single-serve sachets, drinks such as powdered milk and chocolate, malt-based drinks, instant coffee and tea can all benefit from the longevity provided by alufoil helping to make sure that the drink can still be fully enjoyed many months later, even beyond its ‘use by’ date.
Alufoil lined cartons
For many dry food products several versions of alufoil lined cartons can combine technical efficiency with great consumer convenience and attractive graphic design. Powdered food products such as baby milk and drinks such as chocolate and tea can be effectively packed in foil-lined cartons. Some cylindrical designs offer an easy-to-open, fully protective alufoil membrane under a plastic reclosable lid. Rectangular cartons can be perforated at the top seam for easy opening.
Herbs, spices and yeast
A fine example of alufoil’s protective role is the packaging of aromatic herbs and spices. Alufoil has been scientifically proven as a complete barrier for the organic molecules which make up flavour and taste. Dried yeast, a ‘living’ organism, will last for very long periods in the total protection from moisture that an alufoil sachet can provide.
Confectionery
For many types of confectionery alufoil’s barrier and decorative properties can be vital components. Many chocolate products are stored for long periods, but, when exposed to moisture and light, it deteriorates and the surface can quickly lose its attractive gloss. Aluminium foil or laminate offers the best protection, providing a total barrier to light, moisture, and any penetration of aroma and flavour.
Additionally it can be folded tightly to the surface of chocolate. For all types of confectionery, alufoil’s glittering metallic surface also brings colour and impact, adding to the fun and enjoyment of the product.
Chocolate bars
An alufoil wrapper displays quality to the consumer. The crisp, gleaming foil is an assurance that chocolate will be in top condition. What’s more, once part of a tablet has been eaten, the rest can be re-sealed and protected thanks to the ‘deadfold’ characteristic of aluminium foil.
Embossing - the extra design dimension
This shape retention property, unique in flexible packaging materials, offers further design opportunities. The metal retains the impression when embossed, even with a very fine texture, ensuring that the brand stays part of the product until the last portion is eaten. A colour lacquer or printed design on the unsupported foil can further add to visual appeal and enhance brandidentity.
Chocolate novelties
The creativity of the chocolate makers for shapes and novelties knows no limit. There is a chocolate version for every occasion or character – Santa Claus, Easter eggs, rabbits, chicks, Halloween spooks and witches, Valentine hearts, themed fictional characters, gold and silver coins, footballs, sportscharacters, racing cars, and even mobile telephones. The success of such chocolate shapes could not happen without alufoil’s barrier and deadfold characteristic. Also the print quality achievable ensures a strong likeness to the original character or item. Plus alufoil’s appealing metallic glitter and bright colours do a lot to encourage sales and enhance the consumer’s pleasure.
Biscuits and count lines
Specialist foil converters can provide the protection and decoration to suit the product, production, packaging and retailing requirements of the manufacturer. Foil/paper laminates, for example, further extend strength and machinability without sacrificing ‘deadfold’ which is ideal for sensitive snackproducts such as bars and chocolate-covered biscuits. Heat-seal and cold-sealcoatings, film laminations and embossed textures are also readily available. High precision slitting and edge quality also ensure performance on modern high-speed automated packing lines.
Boiled sweets and chewing gum
Foil/paper laminates and twist-wraps ensure quality and enjoyment. Even with individual film or waxed paper wrapping, boiled sugar sweets can absorb moisture and lose flavour unless they are enclosed in a sealed alufoil laminate barrier. Twist-wrapped chocolates and sweets also benefit from the extra brightness and protection of an inner layer of alufoil. Laminated wrappers and ‘tubes’ are widely used to protect many brands of fruit flavoured and medicated lozenges as well as chewing gum products.
Protection against insects
For confectionery sold in warm climates, there are special ‘insect proof’foil specifications. This protection is very effective for products containing nuts or raisins. The heat-seal coating has a very low sealing temperature to protect the product. It is tamper proof, chloride free and FDA approved.
Fresh ideas extend the uses of aluminium foil
Imaginative application of foil-lined cartons can bring a fresh approach to a brand in need of innovation. They provide a long shelf life, are easy to open and sustainable. Push through blister packs are also in growing use to lendlong shelf life to products such as chewing gum.
Remember: The first use of alufoil was for chocolate!
Preserved Food
Extending the viability of foods’ resources has a long history, helping communities to survive periods of shortage. Today, the techniques of foodpreservation have evolved but are no less important in conserving the nutritional value of the food as well as the investment in labour and energy.
Aluminium foil plays a valuable role in modern preservation and deliverysystems thanks to its unique combination of properties.
Heat sterilisation using autoclaves has enabled food products to last, in extreme cases, for years without refrigeration. Even with the trend away from traditional rigid packaging towards lightweight pouches, such as alufoilcontainers and laminated cartons, the same preservation performance, without the weight and transportation demands, is possible.
Pouches and sachets
Retortable ‘stand-up’ pouches are now a common packaging format with the perfection of coatings and laminates designed to resist autoclave sterilisation. An alufoil layer in the pouch is essential for full protection against light and gases. The thin laminate and slim format of the pack enables heat to penetrate quickly to the whole of the product and also to cool very quickly. This means less overcooked product than with traditional cylindrical cans.
Sterilizable pouches are used in a variety of sizes and formats, saving space and resources. Flexible pouches can also be used for three-dimensional products, such as sausages or fish portions, and will take the shape of the contents, excluding oxygen before sterilisation.
High barrier lidding
A high barrier alufoil laminate lid can extend the life of a short lifefresh product due to its heat and pressure resistance. Foil-lidded single or multi-compartment plastic dishes, give long life protection for baby foods, snack meals, soups and vegetables. Canned foods such as fish are now routinely packed using high barrier peelable alufoil lidding instead of heavy gaugering-pulls offering economy coupled with ease of use.
Alufoil containers
Originally used for small portion packs of patés and fruit conserves, sealed smoothwall containers are now used successfully for all types of ‘shelfstable’ foods. Close collaboration between container producers and ink and coatings suppliers, allows the lidded alufoil dish to provide an excellent combination of characteristics. It is compact, attractive in appearance, fully protective, yet easy to open and use.
The lightness of the foil and the stacking format of the empty container offers space and handling economy during filling. The aluminium finish can be enhanced with coloured lacquers and high quality multicolour printing. Development continues with alloy ‘tailoring’, down-gauging and digital printingtechniques, enabling shorter runs, and economy without loss of performance.
Foil lined cartons
Aseptic filling of foil lined beverage cartons has been a highly successful technique. The aluminium foil barrier is a key part of the pack, enabling a shelf life of up to two years. Opening is simple with a perforated tear-off topseam. Cartons save space and resources before and after filling.
Sterilizable cartons are now popular for shelf stable vegetables and meatproducts. The foil-lined carton material makes minimum demands on resources.
Container
Ideal for the automated packaging line, foil containers offer ‘whole life' durability. They can accompany their contents from hot or cold filling through every stage of chilling or freezing, lidding and other packaging procedures and on to distribution, retailing, cooking or reheating and serving by the ultimate consumer. Combining lightness with stackability alufoil containers are easy to store and handle.
Consumers like the value, dependability and versatility of alufoil food containers. Unique in the processing and packaging of human and pet foods, they combine all the features needed to deliver high quality fresh, wholesome and quickly accessed products.
Alufoil containers stay bright and reflective throughout processing and marketing. They can be embossed, colour lacquered or printed with brand identifying designs and colours both inside and out.
They are suitable for grilling, fan and convectioncooking, barbecue griddle and microwave oven and are easy to open, use and dispose of.
A range of purpose designed lidding materials is also available – from straightforward foil/board laminates to more sophisticated coated or laminated alufoil lids that can be sealed to the container rim yet peel off easily when required.
Enormous Choice
Foil’s characteristics offer great scope for the packaging specifier seeking solutions for many kinds of food products. Due to the ready formability and robustness of aluminium foil, a large variety of standard shapes and sizes as well as smooth wall designs are available.
Oval, round, shallow or deep
Shapes and sizes are available for a huge range of products such as fruit flans, deep apple pies, individual steak and kidney pies or large multi-portion catering desserts.
Rectangular shapes of all proportions
For larger containers, extra strength can be designed into the walls. By incorporating corrugated sides, the rigidity of the container can be greatly enhanced.
Compartmented trays
The compartmented alufoil tray can be used for many products, particularly ready meals or mixed dairy and fruit desserts.
Embossing
The intrinsic ‘deformation memory’ of alufoil provides an added opportunity for branding and information. An embossed recycling logo reminds the customer of the value of the used aluminium container – an environmental pack advantage that can be promoted by brand owners.
Lidding choices
The range of lidding options go from the simple folddown rigid foil/board closure to snap-on covers in foil or plastic. Hermetic sealing with transparent films or heat resistant foil membranes is possible with smooth wall trays that have smooth horizontal rims.
Smoothwall dishes
High quality presentation can be greatly enhanced using a smoothwalled design. Suitable as a standard container, the smoothwall lends itself to the premium end of the market, particularly if the outer surface is coloured or printed.
Meat and fish packaging
In the packaging of fresh and processed meat, poultry and fish products, aluminium foil offers many solutions. The consumer is increasingly looking for the convenience, quality and hygiene which alufoil can deliver.
As a barrier in flexible laminates, alufoil is vital for the long-term quality of sterilised pouches and sachets. It is also used for the hygienic retail packaging of fresh fish sold over-the-counter in Europe’s supermarkets. Retailers have discovered the advantages of ready-to-cook packs featuring trimmed fresh meat and poultry cuts and fish in sealed alufoil containers. Another success for alufoil containers is their use for the processing and marketing of pâtés and prepared meat recipes.
There are a great many formats to choose from, all delivering the product in top condition:
‘Ready to roast’ and fresh produce packaging
Deep drawn alufoil containers with smooth shoulder rims have established a growing market for prepared, uncooked ingredients. Meat, poultry or fish pieces are presented in ready-to-cook packs, hermetically sealed and protected with an inert gas to reduce oxidation and extend shelf life. The consumer need not handle the raw product while the alufoil dish acts as a heat-conductive cooking vessel with the potential for secondary uses.
At the supermarket fresh fish counter customers can now enjoy the convenience of hygienically heat-sealed individual alufoil packs. No risk of escaping raw juices and the best possible protection for carrying home.
Smoothwall containers for heat-processed products
Originally introduced for small portion packs of pâté etc., sealed smoothwall containers are now used for many meat and fish-based foods. The outcome of close collaboration between container producers and the makers of inks and coatings, the lidded alufoil dish provides an ideal combination of characteristics. It is compact, attractive, fully protective yet easy to open and use.
The lightness of the metal and the stacking format of the empty container delivers space and handling economy during filling. The aluminium finish can be enhanced with coloured lacquers and high quality multi-colour printing.
Pouches and sachets for preserved meat
Pouches suited for sterilization are used in a variety of sizes and formats, saving space and resources. The flexible pack is easy to open and can be re-closed, excluding oxygen. Full or empty, the pouches occupy a minimum of storage space. Flexible pouches can be used for three-dimensional products such as sausages or fish portions and take the shape of the contents, so excluding air before sterilization.
Peel-off closures
Cans for products such as whole and filleted fish are now routinely packed using high barrier, peelable alufoil lidding instead of heavy gauge ring-pulls. This offers consumerconvenience and decorative potential. Also, foil-lidded single or multi-compartment alufoil or plastic dishes can provide long life protection for meat-based baby foods, snack meals, soups and other recipes.
Dairy
As a robust and non-corrosive material, aluminium foil has played a keyrole in the packaging of dairy products. Alufoil helps to retain essential quality, condition and taste until the moment of use.
Milk, cream and yoghurt in beverage cartons
Milk, cream and yoghurts packaged in sterile cartons makes it possible to preserve their intrinsic properties, without refrigeration, due to a very thin layer of aluminium foil. These long-life packs are impervious to light, odour and gases, while at the same time providing a crucial barrier to light and oxygen and the preservation of essential vitamins. Such aseptic cartons are lightweight and designed for efficient transportation, storage and on-shelfdisplay. Most importantly, without the need for refrigeration due to the alufoil layer, considerable savings in energy resources along the supply chain can be achieved.
Lidding for dairy products
Traditionally lids were embossed to ensure reliable handling on the liddingmachine; today they can also be supplied without embossing. The separationcharacteristic is provided by a pattern of ‘dots’, messages or logo designs printed on the inner sealing side.
Opaque lids for dairy product containers can help to extend shelf life by protecting the sensitive contents from direct exposure to the strong fluorescent lighting in refrigerated supermarket display cabinets.
An alufoil closure completely eliminates spoilage due to exposure to the atmosphere and deterioration during storage.
Cheese packaging
The packaging requirements of cheeses vary according to their individual characteristics. Not all cheeses benefits from being wrapped in an impervious, light and moisture-proof material and some require gas permeability for successful ripening.
Processed cheese portions
Where a total barrier is required, as in the case of processed cheese products, aluminium foil provides ideal protection and attractive portion presentation. The ‘dead-fold’ nature of the foil, even when laminated to a paper substrate, gives full control during and after the wrapping process. With processed (sterilised) cheese portions, the foil is edge-sealed and an easy open tear tape can be built into the portion packaging to facilitate opening.
Soft cheeses
Attractive alufoil packs continue to attract consumer attention in the coolcabinet. For many well-known brands the bright foil packaging is an intrinsic part of the product. As well as prolonging the shelf life of the cheese by protecting it from drying out or the effects of light and odours, the decorated alufoil laminate maintains the brand presence until the last portion has been used.
Cheeses in foil containers
Alufoil cheese packaging is not only available as a wrapper. An example of an alufoil container application is the packaging of spreadable cheeses by Tine, a Norwegian dairy product manufacturer. The company chose a range of specially designed and decorated aluminium containers with attractively printed alufoil peel-off lids and plastic covers.
Heat-sealed caps and diaphragms for milk drinks
The compatibility of aluminium foil with heat-seal lacquers, coupled with the metal’s excellent heat conductivity and stability, makes it the ideal material for capping and heat-sealing of all types of plastic milk containers. Whether the milk is fresh, aseptically filled or sterilised in the container, the foil/coating combination can be designed to meet the demands of processing and distribution. A foil diaphragm solves the problem of achieving a reliable screw-top closure for blow-moulded milk bottles. This is heat-sealed to the bottle opening using induction heating. Only the metal foil becomes heated by a high frequency electro-magnetic field which is applied after filling and capping. Although reliably sealed, the foil can be peeled away cleanly thanks to coatings that combine seal strength with peelability.
Butter Wraps
As well as reducing the nutritional value of a dairy product such as butter or a vegetable fat, photo-oxidation caused by UV light spoils flavour and appearance. An alufoil wrapper stops this damage. Also, the extra feel and look of quality that a laminated foil/paper wrap brings to the pack ensures outstanding shelf display.
‘Knife-proof’
Developments in the design of butter and fat wrappers have included the introduction of tough puncture resistant and even ‘ice proof’ laminates. The freeze and thaw resistant butter wrapper overcomes the problem of moisture condensation which can sometimes cause delamination when a traditional foil/paper wrapper is thawed.
Dairy desserts in alufoil containers
For heat-processed dessert products the alufoil container has several advantages. The entire pack is opaque. No deterioration due to UV light is possible. The conductivity of the alufoil allows rapid heating, minimum processing time and rapid cooling. The decorative potential of the container is high. In the case of the smoothwalled container format, pre-distorted printing allows for excellent graphics on the shaped dish. In a similar way to yoghurt or cream, lids can be decorated and either embossed with a pattern or entirely smooth.
Ready Meals
The market for ready meals has expanded relentlessly in the past decade. New processes and the increasing demand for greater convenience has increased the variety of foods on offer and improved the quality. At every stage of this expansion aluminium foil has played a primary role in these developments.
More detailed information about the LCA of "Lasagne" can be found here.
Home meals
Whether in the form of a lacquered and compartmented individual dish or a traditionally formed tray, alufoil containers can resist almost any cooking and freezingtemperature and can be lidded in a number of formats. Once used, they can be put into the aluminium recycling system for clean, efficient metal recovery.
Fresh meat or fish recipes
Deep drawn alufoil containers with smooth shoulder rims have grown the market for prepared meals consisting of meat joints and fish dishes. Small meat and poultry cuts can be presented in the ready-to-cook tray, hermetically sealed and protected with an inert gas to reduce oxidation and to extend shelf life without loss of quality. The consumer does not need to handle the raw meat or fish while the dish acts as a heat-conductive cooking vessel with the potential for secondary uses.
Airline meals
Light, quick to re-heat, strong and consumer-friendly, alufoil containers enable millions of airline passengers to enjoy hot food. The surfaces can be lacquered to conform with the airline's corporate style and embossed with logos or messages. Clip-on alufoil lids can be colour coded or embossed according to the contents without spoiling the presentation. As with all alufoil containers, the used dishes can be passed directly into the recycling system.
Enormous Choice
Foil's characteristics offer great scope for the packaging of many types of chilled or frozen ready meals and desserts. The ready formability and robustness of aluminium foil means a large variety of standard shapes and sizes is available. This enormous choice ranges from a tiny dish 35mm in diameter to the biggest catering size measuring 527 x 325mm, with nearly ten litres capacity. Between these two extremes there are hundreds of shapes and sizes, many with a choice of rim configuration.
Unique performance
Ideal for the automated packaging line, foil containers offer ‘whole life' durability. They can accompany their contents from hot or cold filling through every stage of chilling or freezing, lidding and other packaging procedures on to distribution, retailing, cooking or reheating and serving by the ultimate consumer. Combining lightness with stackability containers are easy to handle and store. They are suitable for all types of cooking and re-heating: grilling, fan and convection cooking, barbecue griddle and microwave oven and are easy to handle, open, use and dispose of.
Pharma and Healthcare
Many of alufoil’s properties combine to provide user-friendly, safe and versatile packaging formats for pharmaceutical tablets, creams, liquids and powders. Alufoil’s excellent barrierproperties totally exclude moisture, oxygen and other gases, micro-organisms and light, maintaining degradable products in peak condition over long periods.
Foil comes in a completely sterile condition due to the annealingtemperature and final conditioning processes. It is not hazardous to health, and many suppliers offer dedicated ‘clean-room’ printing and laminating or printing and packing facilities to ensure medical standards of sterility.
Applications:
Blister packs
Alufoil is particularly suitable for blister packs because of its range of mechanical properties. Depending on the alloy and its treatment, alufoil can be made more brittle, tougher or more ductile. It can also be combined with other materials like paper or plastics. Blister packs are tamper-evident and can be designed to be ‘child-proof’ or to provide more secure access.
Most blister packs consist of a preformed plastic tray with an aluminium foil closure manufactured to facilitate the necessary ‘push-through’ characteristic. A recent development is the all-aluminium blister pack. The cold-formed trays are filled with the medicine in aqueous form and freeze dried into individual tablets, which adopt the shape of the individual alufoil compartment. All-aluminium packs are also used for diagnostic products, ointments, and light sensitive formulations where total barrier performance is required. As product counterfeiting has become an increasingly serious issue, holographic effects are now being used on more and more alufoil blister packs.
Strip packs
Strip packs can be produced entirely from aluminium or in combination with paper or plastics, all of which are printable. A key requirement is the ability to tear open easily. Alufoil’s malleability and deadfold characteristic are important in these applications, allowing the metal to closely match the shape of the tablet. Strip packs provide economical high barrier performance and can be filled at high speeds on sterile filling lines.
Sachets and pouches
The sensitive nature of most pharmaceutical preparations demands that the packaging provides a perfect barrier to moisture and often to light. Alufoil laminated sachets provide packaging solutions for many products, whether in powder, cream or liquid form. Large alufoil pouches are also used to store, transport and dispense sterile fluids used in hospital treatments.
Alufoil sachets are robust and keep the product in good condition over long periods. They withstand rigorous ‘burst’ tests and are convenient and economical to transport. Printed designs, colour coding and anti-counterfeiting finishes are available.
Heat sealed membranes and closures
Many medicines are supplied in glass, plastic or metal containers. Alufoil, laminated with paper or plastic, is frequently used as a heat-sealed membrane hermetically closing the container, usually under a plastic screw cap. The localised heat needed to affect the sealing process is generated by an electrical induction process after the screw caps are applied on the filling and capping line. The resulting alufoil membrane provides excellent barrier properties preventing moisture or gas transmission as well as tamper evidence. Safety information can be printed on the alufoil seal if required.
Collapsible tubes
Alufoil is frequently used as a key component in tube laminates. Apart from providing excellent barrier performance to protect sensitive creams, alufoil offers the advantage of ‘deadfold’. So a tube made with alufoil laminate can be designed not to ‘spring back’ when squeezed, which can draw ambient air and contamination back into the tube. Tubes with holographic or other optical effects are available. In addition to decorative design opportunities, these surface finishes can be used as valuable tools against product counterfeiting.
Cosmetics and Personal Care
Cosmetic products are fun, but often expensive and need to be wellprotected to give their best performance.
Alufoil is used extensively in the packaging of many cosmetics and personalcare products, although often hidden from sight. It plays a key part in their physical protection, while the metallic glitter can be used to great effect to enhance the excitement and prestige of many pack designs.
The science of cosmetics is very sophisticated – with the application of special oils, vitamins, herbal and chemical compounds – so the need for full protection from light and contamination is increasingly important. Such products may need a long shelf life both in the shop and after purchase. The complete barrier properties of alufoil can help to ensure this, coupled with exciting visual appeal and due regard to the demand for environmentally responsible use of materials.
Sampler and single dose sachets
The widest use of alufoil-based flexible packaging for cosmetics is as samplers or single dose sachets. They are popular for shampoo, after-shave, skin lotions, bath oils, liquid soap and perfume.
As samplers, alufoil sachets withstand the rigours of magazine and mail distribution where one of the tests is to withstand a pressure of 1.5 tons for 6 seconds. The graphic design of a sample sachet can be made to imitate the shape, colours and textures of the full size version.
Diaphragms
Alufoil is used to seal the opening on jars of face cream. As well as acting as a very effective tamper-evidence feature, the alufoil prevents the product deteriorating during distribution and storage. The alufoil, usually printed, provides an opportunity to use anti-counterfeiting holograms or other features. They can be crimped over the top of the jar or, more frequently, heat sealed to provide a more secure closure Sealing system suppliers recently replaced conduction heated seals with a much faster induction heat-sealing process. This uses a high frequency microwave electrical field to precisely heat the seam area. A strong-coated alufoil material is also less prone to tearing when removed.
Flexible pouches
Flexible alufoil laminate stand-up pouches, fitted with a spout and closure, have become excellent and fashionable alternatives to bottles. The packs are light, tactile, and offer special opportunities for graphic treatment. High barrier pouches are also used inside aerosol containers for ‘airless’ sprays to separate the propellant gas from the active ingredients making up the product.
Blister packs
Blister packs rely on the complete barrier properties of alufoil coupled with the ‘burst strength’ designed for convenient access to the contents.
There are many innovative blister applications, such as dual blister technology which enables the contents of two separate compartments to be mixed, when required, before opening the pack. It can be used for a cosmetic facemask where the lotion is held in one compartment and a dry tissue in another. Squeezing the liquid chamber moistens the tissue which can then be removed, unfolded and applied..
For perfume sampling, a blister-based pack allows small quantities of only 0.25 ml of perfume to be tested in realistic conditions by vaporising the product, like a miniature spray. The alufoil laminate backing prevents the perfume vaporising or degrading prior to opening.
Tubes
The construction of collapsible tubes used for creams and gels is another, often hidden, application of alufoil. The metal layer maintains the quality of the product against the damaging effect of light and adds deadfold characteristics to the laminates. Deadfold means the tube made with alufoil laminate, once squeezed, remains squeezed and will not spring back to draw in air and micro-organisms, so avoiding the ingress of contamination and maintaining a high level of hygiene.
For many cosmetic creams, which contain oils, water and vitamins, this can mean the quality and viability of the product are extended for the whole of the likely period of use. In addition anti-counterfeiting holograms can be used with alufoil laminate tubes.
Wraps
Deadfold, along with other alufoil properties, is valuable in more traditional applications such as wrapping luxury soaps. Alufoil’s impermeability helps to retain fragrance and provides excellent folding characteristics, while the high gloss metallic print surface can be put to good graphic use to convey product quality.
Tobacco
Tobacco is a perishable and often expensive consumer product and requires packaging that delivers it to the consumer in the very best of condition. Alufoil has been an integral part of this process since the 1950s.
The packaging of tobacco products calls for a careful balance between the protection of a sensitive and aromatic natural product and the presentation of brands striving for individual identity and appeal.
Aluminium foil has become the preferred barrier material, particularly for the inner liner of cigarette packets. This is because it combines the ability to retain the characteristic aroma peculiar to each blend and brand, within aunique quality of ‘feel’ and appearance which is light, robust and easy to re-seal. An aluminium foil/paper laminate also offers mechanical qualities not available in alternative materials.
Cigarette inner liners
Liners are the most familiar and significant use of alufoil due to its unique combination of barrier, embossing, deadfold and web strength properties.
The total barrier nature of an alufoil laminate is well illustrated by theretention of the added aroma when menthol is added to a cigarette linerlaminate. The foil enables the menthol to permeate within the tobacco but prevents it from escaping to the outside of the pack. Also, added productidentity can be given by the use of embossed designs – textures, lacquercolours and logos.
Carton laminates for cigarette packs
Foil enhances the quality appearance of several premium cigarette brands, at the same time helping to protect important product components such as moisture and aroma. Embossed logos and designs keep their shape because of the alufoil layer.
‘Soft’ cigarette packets
The advantage of foil’s deadfold is combined with its barrier benefits to produce soft packs.
Loose tobacco
For those who prefer to make their own cigarettes, foil’s deadfold property allows temporary re-closure of packs of loose tobacco, conserving moisture and aroma.
Over-wraps for multi-pack cartons
Decorative foil laminates for large cartons of cigarette packs effectively retain the essential characteristics of the tobacco for extended periods.
Cigar sleeves
Used for some smaller cigars, these are an effective equivalent to the traditional aluminium screw-topped tubes used at the luxury end of the cigarrange.
Pet food
The demand for time-saving convenience coupled with high quality in terms of nutrition and taste has been as much to the benefit of cats, dogs and other domestic pets as to their human owners.
From a position of having no products in this market alufoil containers have become a major packaging format, being sterilisable while at the same time bringing visual appeal, lightweight, ease of use and full product protection to the ‘moist’ pet food category. Today flexible alufoil laminates provide even greater choice through sterilisable pouches and cartons. Brand owners can choose the right format to suit the requirements of both animals and their owners.
Retortable alufoil containers and lids
The outcome of close collaboration between container producers ands pecialist inks and coatings manufacturers, the lidded alufoil dish provides an ideal combination of characteristics to make it a highly successful pet foodpack. It is compact, attractive in appearance, fully protective yet easy to open and use. The lightness of the metal and the stacking format of the empty container achieves space and handling economies during filling. The metallic finish can be enhanced with coloured lacquers and high quality multi-colourprinting. Development continues through alloy ‘tailoring’, down gauging and alternative printing techniques, designed for shorter runs without loss of performance or added costs.
Flexible pouches
Retortable ‘stand-up’ pouches are now an everyday packaging format with the perfection of coatings and laminates designed to resist the rigours of autoclave sterilisation. To guarantee the integrity of the product, an alufoillayer is essential for protection against light and gases. As with shallow alufoil containers, the thin laminate and slim format of the flexible pouch enables heat to penetrate to the whole of the product and also for it to cool very quickly. This means less overcooked product than with traditional, cylindrical cans. Pouches, which can also be used for non-sterilised dry pet food products, are easy to tear or cut open and can incorporate a re-sealable component.
Cartons
A major breakthrough for flexible packaging into the ‘canned food’ market was the first fully retortable, foil-lined carton system. The flexible alufoil laminate is used to form rectangular containers which undergo heatsterilisation. The aluminium foil barrier is key and permits a shelf life of up to two years. Opening is simple thanks to a perforated seam at the top of the carton. The foil-lined material requires a low level of resources.
Household foil and domestic uses
Throughout Europe most households are used to having alufoil in the home. It has become an essential part of modern household convenience – for cooking, reducing cleaning chores in the kitchen and for its many uses around the home, garden or workshop. In commercial kitchens too – restaurants, canteens, schools and hospitals – foil is a tool with many functions.
Alufoil’s total barrier to light, steam, aromas and liquids is a major reason for its use in the kitchen.
The same properties can be used to stop evaporation and drying of paint, adhesives and fillers used in home decoration.
Also it can deal with the highest temperatures encountered in cooking, whether in a convection oven or under the hottest grill. Another great advantage when used in the kitchen is the ‘deadfold’ characteristic of aluminium foil. Once folded around a joint of meat, or crimped onto the top ofa casserole or storage pot, the alufoil stays folded and does not spring back.
In the kitchen the main domestic uses are:
to reduce burn and shrinkage when roasting poultry and meat;
cooking delicate fish and vegetables ‘en papillote’;
lidding storagepots (not steel cans);
protecting parts of poultry from microwave* ‘burn’;
making small storage containers for the refrigerator;
wrapping for the freezer;
covering saucepans to retain steam;
baking ‘jacket’potatoes;
lining cake tins,‘lift-out’ strips;
wrapping sandwiches and snacks;
keeping food and ‘left-overs’ in the refrigerator – cakes, meat, fruit;
saving cleaning –lining a grill or the oven floor;
Foil formats:
Household foil is available in a variety of formats. In addition to a range of widths and lengths there are textured versions and ready-cut sheets, making it easy to use without unreeling and tearing. ‘Non-stick’ foil can solve many problems, such as baked-on food. Another special foil is black on one side, which transfers radiant heat more efficiently from the black side, making it ideal for roasting.
Around the home:
used to prevent paintbrushes and other decorating materials from drying out;
making temporary trays for roller painting;
drip trays to catch oil from garden machinery, cars, etc.;
making reflectorboards for amateur photography;
temporary reflectors for lamps and candles;
lining bases of flower pots;
protecting shelves and adding reflected light in the greenhouse;
lining cupboards where foodstuffs are stored;
making decorations;
lining barbeques;
*Microwave oven uses: As microwave energy cannot pass through metal, alufoil is very useful for protecting some parts of food from being dried or over-cooked in a microwave oven. To avoid the possibility of arcing, any foilused in this way should not touch metal shelves or the inner metal lining ofthe oven during cooking.
Technical Applications
Heat exchangers
Its high thermal conductivity, coupled with comparatively low cost and ease of working, makes aluminium the metal of preference wherever heating or cooling is required. By the use of foil gauges the maximum surface area and minimum metalcan be used to transfer heat. Aluminium foil allows a high level of energyefficiency within the smallest possible space. The metal’s low weight alsosaves the amount of structure needed to house or to carry aluminium-based heatexchange units.
Such considerations are important where, for example, the heat exchanger isused in aircraft, cars and trucks. Weight and space saved in all forms of transport mean ‘knock-on’ efficiencies in fuel and vehicle capacity.
In homes, offices and factory buildings compact heating and airconditioning units allow the architect or designer great flexibility in the location and format of equipment. Alufoil offers a high level of corrosionresistance, so that no protective coating or finish is usually necessary andmaintenance is minimal.
Due to aluminium’s recyclability the used metal is available for re-use after the heat exchange equipment has completed its useful lifespan. Both static and mobile heating and cooling installations incorporate aluminium foil,making a significant contribution to efficiency and sustainability.
Typical Heat Exchange Applications for Alufoil:
Buildings
For heating, de-humidifying and air conditioning systems, alufoil heatexchange units perform effectively in every climate, helping the occupants of modern buildings all over the world to work and live in comfort.
Cars and trucks
Automotive fin stock and brazing strip are highly engineered products, requiring superior gauge control capabilities, precise thickness and width tolerances as well as exacting chemical and physical properties. Almost everyroad vehicle built today carries heat exchangers incorporating aluminium foil.Engines, oil coolers and climate control equipment all rely on the lightnessand conductivity of finned aluminium heat exchangers. They save weight, reducefuel demands and maximise the efficiency of each vehicle.
Aircraft and ships
Oil coolers, air conditioning units – everywhere that heat needs to bedissipated or enhanced – will usually incorporate an aluminium foil finned heatexchanger.
Refrigeration
Food processing plants require freezer and refrigeration equipment for foodhygiene and safety. Wherever food is shipped, stored and sold there is a need for efficient cooling. Display cabinets for chilled or frozen products are standardequipment for supermarkets. Alufoil is present in all of them.
Foil specifications:
A range of aluminium alloys and dimensional specifications is available to meet the technical demands of the design and production method involved. In addition to plain alloys, compatible with many joining techniques, special‘clad’ materials are available combining the formability and thermal propertiesof a base alloy with the surface durability and joining characteristics ofanother alloy.
Automotive
Its unique combination of properties makes alufoil an indispensable material in vehicle components - for ducting, energy absorption, noise attenuation, heat exchange, insulation and decorative trims.
An outstanding success recently is the total replacement of copper by aluminium foil in heat exchange components, such as engine coolers (or radiators) and vehicle air conditioning units*.
Used in hoses and tubes, alufoil helps to protect cables and electricalcircuits from heat and contamination, to deliver warm or cool ventilation and reduce noise levels. In ‘honeycomb’ and composite tube forms, aluminiumfoil plays an important role in vehiclesafety.
As part of internal linings and vehicle ‘fire walls’ alufoil is used in insulation composites, adding only minimally to weight. It is also present in ‘sandwichconstruction’ under body heat shields on most cars and trucks as well as theengine bay environment, especially adjacent to exhausts, catalysts and DPFsystems.
The metallic sheen of alufoil is commonly used in decorative trim for cars, buses and caravans. Changing designs and regulations have meant that this use has fluctuated over the years, but new embossing and laminating techniques arenow prompting renewed interest.
Heat exchangers
Vital to the efficient operation of a vehicle’s power plant and to the comfort of the driver and passengers, aluminium-finned heat exchangers provide both cooling and heating as required. Because of its light weight and due totechnical developments in alloys and joining techniques, aluminium has becomethe primary choice.
Impact protection
Laminated and corrugated foil/fibre tubes and sections offer lightweight energy absorption solutions, used to line interior surfaces and to protect passengers in the event of accidents. Energy absorbing alufoil honeycomb canalso be used as part of structural protection against certain crash scenarios,such as interior head impact.
Heat protection tubes
Made of several layers of different materials, including aluminium foil wound with corrugations, heatprotection tubes are flexible. Using alufoil’s reflection characteristics on the outer layer, these tubes ensure protection against radiant heat. An insulationlayer on the inside provides additional protection to the component against thetransfer of heat. The tubes are very flexible and dimensionally stable. Theycan be used to protect any kind of hose, tube, conduit and ducting, as well ascable and wiring systems.
Ducting
Flexible corrugated tubes created from aluminium foil - often laminated with fibre and other substrates depending on their function - provide the essential ducts for heating and cooling ventilation and for the protection ofcables and articulated components. The ducts are light, durable and fireresistant.
Linings and firewalls
The durability and fire insulating properties of aluminium foil qualify it for use in several components. It adds dimensional stability and permanence to soft linings in passenger compartments. It lends security against the spread offlame thanks to its incombustibility and heat conductivity. Passenger comfortis also enhanced through the reduction of noise levels using sound absorbentfoil laminated tubes and padding components.
Decorative trim
An economical and long lasting solution where a metallic trim is required, laminated or encapsulated aluminium foil is often specified. New alloys, brushfinishes, anodising, embossing and coating techniques have extended the use ofalufoil and thin strip into some demanding applications such as doorsills andfingerplates.
Alufoil and thin strip specifications
A range of alloys and dimensional specifications is available to suit the technical demands of the design and the production method involved. In addition to plain alloys, compatible with many joining techniques, special ‘clad’materials are available combining the formability and thermal properties of abase alloy with the surface durability and joining characteristics of anotheralloy.
Insulation and Cable wrap
Whether the insulation task involves heat, light, sound, moisture or gases, aluminium foil is a high performance material. Its highly reflective surface has, for example, earned it an indispensable place inthe insulation of domestic, commercial and industrial buildings. In ducting andpipework too, where the suppression of heat loss or gain is essential,alufoil’s reflective (up to 98% of light and infrared heat) and barrierproperties make it the material of choice.
The versatility of aluminium foil – easy to laminate, to shape and to coat with a protective lacquer – takes into a great variety of situations. Its insulation role extends into fire protection. In ‘fire walls’for vehicles and ships, for fire-resistant doors and building panels, aluminiumfoil with its melting point of around 660 °C and its heat conductivity dissipatesheat and stops access to the oxygen required to support flames.
In electrical cables, aluminium foil is an essential component providing long-term protection. It also insulates against magnetic and radio frequency emissions. Used in fibre-optic cables, aluminium foil actsas a ‘tracer’ to enable testing of the integrity of cable links.
Applications:
Building insulation
Efficient wall insulation saves costs and floor space.
A foil-base insulation layer can avoid the need for an inner brick skin. The inner surface is an insulated framed dry lining. A foil-foam lining reduced the wall thickness and maximised the available floorspace in an apartment building.
Maximising available light
Alufoil laminate doesn’t only help to keep temperatures under control, the highly reflective surface can make the most of available and artificial light – an added cost saving.
Pipework insulation
Pre-formed phenolic resin pipework insulation with a protective coat of alufoil. Adding to the insulation, the foil also protects the surface of the plastic from damage.
Adhesive tapes
Highly reflective and durable alufoil adhesive tape is available in widths up to 30 cm. As well as efficiently joining insulationmaterials in, for example, pipework installations, self adhesive alufoil may beused for small scale tasks such as RF screening in electronic equipment etc.
Health and safety
Insulation is not just for buildings. This fast ferrycar deck is lined with an insulating and fire resistant alufoil composite, so enhancing passenger, vehicle and vessel safety.
Roof insulation going into place on a large warehouseproject. The work is fast and efficient and poses no occupational healthproblems – no need for special protective clothing or other safety measures.
Ensuring efficient cabling
In communication cables, aluminium foil gives long-term insulation against moisture and attack from naturally occurring corrosive elements found above and below the ground. Aluminium foil also actsas an insulator against the magnetic and radio frequency fields associated withmetal electrical cables.
As a sheath for fibre-optic cables, aluminiumfoil’ electrical conductivity enables the testing of the integrity of cablelinks.
Honeycomb structures
Aluminium foil demonstrates some distinct properties when used in the construction of honeycomb cored panels and structures. Sandwiched between aluminium sheets, the layers of alufoil, joined together and expanded into anopen-celled honeycomb format, provide an extremely strong yet light core. Theresulting panel out-performs competitive materials in strength to weight ratioand lightness, also in terms of rigidity and flatness under load.
The surfaces can be finished according to the needs of the application –aluminium alloys for aircraft components, metal tread plates for floor panels, marble or stone for interior décor, or external cladding, paint or plasticsmaterials for displays or cabinet enclosures.
This material enables architects to lighten building structures and foundations, engineers to save weight in all types of transport – ships, planes, trucks and cars – due to the properties of the aluminium foil corematerials.
Architecture
Lightness, durability and flatness means alufoil honeycomb-cored panels are specified for architectural cladding in many forms. Decorative bonded skins involving marble, granite, untreated or anodised aluminium (in colours oruncoloured) or coil coated lacquers, etc. make these lightweight panelssuitable for all types of building – commercial, industrial or domestic. The resulting weight economies lead to significant cuts in the load bearingstructure and in foundation work. These can mean big reductions in the amounts of materials needed and the costs of construction. Honeycomb panels also add sound insulation properties to exterior cladding.
Signs and interior displays
Outstanding flatness makes alufoil-cored a primary choice for fascia panels and road signs. Aluminium honeycomb panels can be shaped and formed to make curves and bends. Lightness helps in the handling and assembly while itsdurability means these signs and displays have a long useful life. Maintenance,when required, is minimal.
For interior displays and exhibition stands great savings can be achieved by incorporating lightweight, long life and durably finished honeycomb enclosure panels.
Transport
All aluminium applications in the transport sector using strong and durablehoneycomb panels save deadweight and add to the amounts that can be carried. This, in turn, saves on vehicle usage, fuel consumed and emissions. Future lowemission and alternative fuel systems are likely to require the construction ofvehicles to an absolute minimum of weight. Aluminium foil honeycomb offers many solutions in this respect.
Impact protection
Aluminium honeycomb material can provide a high level of energy absorption when designed into impact protection components for vehicles. Studies carried out with car manufacturers have demonstrated that the honeycomb-based elementshave a constant strength and a controlled level of deformation. In a longitudinal force experiment the deformation elements were compressed to 30% of their original length and absorbed large amounts of impact energy, reducing the effects on other structural components.
Manufacture of honeycomb panels and structures
A wafer block of aluminium foil core material is stretched into a sheet of hexagonal structure on purpose built, CNC equipment to give a consistent celldimension. The walls of the cells can be micro-perforated to allow movement ofair between adjacent cells, equalising pressure in environments with rapid temperature variations.
The expanded core is bonded to the outer facings with a two-part adhesive which is applied in a dedicated computer controlled spray booth facility. This allows close monitoring of coat weights and accurate application to allsubstrates. The sandwich faces and core are laid up and accurately aligned prior to transferring, by means of roller, table to the press.
The final bonding process is done on a heated, hydraulically operated press to ensure uniformity of each panel and is closely controlled to ensure reliability of the bond.
The cell size, depth of material, thickness of cell walls and aluminiumalloy are all varied to suit specific requirements and tailored to impart the correct, specified properties in the final manufactured units.
Aluminium foil and microwave ovens
The use of alufoilcontainers in microwave ovens is safe
Conclusive evidence that aluminium foil packaging can be used safely in microwave ovens has been established by a study from the Fraunhofer Institute for Process Engineering and Packaging IVV in Freising, Germany.
The results dispel the myth that aluminium foil containers are unsafe for use in microwave ovens and prove that consumer fears about using alufoil packs in the microwave are unfounded.
In fact in some instances consumer convenience is improved as not only are alufoil packs more rigid, something that is equally applicable to dual-ovenablecontainers, the use of aluminium foil enhances the appearance of the food whenheated in the microwave oven. For example the study found that in the case of lasagne heated in a microwave oven its visual appearance was superior as a brown crust was formed on the surface.
Conducted on behalf of the European Aluminium Foil Association (EAFA) with the support of the Aluminium Foil Container Manufacturers Association (AFCMA)the study concluded, “Microwave heating of food packaged in aluminium foiltrays or in plastic containers with aluminium foil or aluminium laminated lids is perfectly viable.”
No hazardous results or damage to ovens were found in the more than 200 food portions that were heated in aluminium foil containers or packs containing aluminium foil. Thomas Pfeiffer, the study’s author, said, “The FraunhoferInstitute conducted the heating procedures with the microwave ovens set at maximum power and there was not a single case of damage to the microwave ovens or danger to the users.”
Four kitchen microwave ovens were used to test aluminium foil trays containing tap water, egg batter, frozen lasagne and minced meat. Tests were also conducted on plastic cups and plastic trays containing a noodle soup and a children’s menu, covered with either aluminium foil or aluminium laminate lid.
The study found some differences in the time needed to heat products when aluminium foil containers were compared with plastic trays. Due to variations in heating patterns and depending on tray geometry and food type, heating times for aluminium foil packs were sometimes longer.
However, observed Pfeiffer, “The study also provides some interesting results regarding heating patterns and heating uniformity. In some cases they appeared to be better in aluminium foil trays.”
*Info from The European Aluminium Foil Association e.V. (EAFA)*
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