Material witness

Want to be a top packaging designer? Then you need a sound understanding of materials and how they affect what you can create.

Packaging designers are a curious bunch - not figuratively, but literally. They have to be, because creating packaging that succeeds on every level requires an enquiring mind able to explore, build, test and innovate using an almost inexhaustible combination of materials. There are no shortcuts, no ready works of reference.

Kite Packaging is typical of the kind of company that supplies the packaging industry with both materials and expertise. Typically, its customers spend more than £100,000 a year on packaging, and come from the automotive, electronic, pharmaceutical and traditional manufacturing sectors. "With packaging there is never a right or a wrong answer," confirms managing partner Gavin Ashe. "There's always a series of compromises. The truth is that 99 per cent of people would actually like to send their product to market with no packaging if they could get away with it."

On the other side of the industry are packaging design consultancies, such as The Packaging Partnership, a Centre of Industrial Collaboration that draws upon expertise from the academics at Sheffield Hallam University, where it's based. The Packaging Partnership is able to call on specialist expertise from the university in areas such as materials science to devise special coatings for packaging, or product design to help to develop plastic mouldings for special types of seal.

Project leader Janet Shipton reinforces Gavin Ashe's view that there are no absolutes when it comes to packaging materials. She says: "In the various roles I've worked in as a packaging designer, marketers or other designers have often approached me asking for a simple guide to pack format and what materials to use. I've always told them the same thing - that if you're doing a job properly then the material requirements will be unique to each individual job."

She continues: "There's no list of guidelines stating that one material is better than another. Choosing a material depends on the brief, on whether the product requires clarity, what type of protection it requires, where it's sold, how far it's got to travel - there are so many different factors.

"If it was a food product, I'd be looking at the protection that the food needs from the environment, and the protection that the packaging and the external environment needs from the food. The customer doesn't want to get contaminated by the food and, likewise, the packaging has to remain intact."

To see or not to see
Marketing requirements have a massive impact on choice of material, too, says Shipton. "There's always a visibility consideration; sometimes there's a requirement for a product to be seen, and sometimes there isn't. With a bag of salad, for example, you'd want a clear packaging so you could see all the different colours of leaf. If it were a frozen product, you probably wouldn't want to see it because it wouldn't be looking at its best. Here, you'd go with an opaque material and rely instead on photography and print to market it."

Once a material has been decided upon, then the implications for design and print must be taken on board. "The type of material you use impacts a lot on what you can do creatively," says Shipton. "With certain materials and certain pack formats you have to use certain print processes, and these can restrict your design. For example, gravure and flexo print processes are suitable for flexible materials, while offset litho is suitable for metals and tin. We talk to printers to make sure we're choosing the right material and right print process."

Printing processes
Designers who become involved in package design from a graphics perspective can be caught cold by the complexities of printing on different materials, as London-based designer Kate Allen discovered recently when designing artwork for a range of low-cost cleaning products.

Allen says: "The labels were for washing-up bottles and cardboard washing-powder boxes. They were being printed in Poland for the UK market. I had to work back and forth between the printer and the manufacturer. They were using a flexo printing process, and I had a lot of problems with it because I'm used to offset. I had drop shadows and Pantone colours, only to find out that you can't overlap these on a flexo press. They took my designs and redesigned them so they would work."

Regardless of materials and print processes, the core consideration for package design consultancies like The Packaging Partnership is to "present the brand proposition through the packaging," says Shipton's colleague, commercial director Andy Toward. "To this end," he says, "we look at everything - material, shape, size, the way it opens, and the graphics. If we're working on a paperboard product then we'll get some paperboard and rough it up, and build a model."

"Our customer will tell us what the packaging needs to do, and with the help of materials experts and packaging manufacturers we'll start testing things," Shipton confirms.

The testing process is critical for learning the capabilities of different materials in varied configurations, and Toward says failure is an integral part of the process. "Some of the time you do a concept and the material may look favourable, but in the development you realise it can't actually be achieved in the way you thought. We know a lot about masses of different materials and manufacturing processes, but we wouldn't expect any of our team to be functional specialists in any one of those areas. We need to know enough to be able to identify whether or not something is possible."

Seek advice
For high-level materials and printing know-how, The Packaging Partnership and consultancies like it will approach the supply chain.

"We know printers, material suppliers and packaging suppliers," says Toward. "We'll show them what it is we're trying to do, and they're usually willing to come in and offer advice free of charge because they're pitching to manufacture the product."

Cost is another factor that impacts massively on the final choice of material, although it's a decision usually taken by clients, not designers.

Again, there is no easy-reference table that can be used as a guide. "Packaging has huge economies of scale," explains Ashe. "Certain products are very expensive if you want small volumes. If you want thermoform printed plastic for less than one million units, it would be way more expensive than if you were above that mark.

"Take a disposable razor, for example. You can pack it in solid board cartonboard with a nice-quality colour print. This would be very cost effective up to several million units, but would really come into its own in the 0-5,000 production range. This is because it has low costs of origination, and is fairly simple to specify.

"Or you could pack it in printed thermoform plastic. The origination costs would be significant, and calibrating the machinery would be very expensive, but once you got over a couple of million units it would probably be the lowest cost of any material suitable for the job."

Where designers do have a more direct impact upon production costs is in the intricacies of their design, Ashe says: "Take a cartonboard package, like a cigarette or chocolate box. The price will depend on print effects, such as embossing or foil block, and whether it's got a tear strip in it. These sorts of details hugely affect the price."

There's a huge range of packaging materials to choose from. Here are some of the most popular examples€¦

More commonly known as cardboard in the UK, paperboard is similar in shape and composition to paper, but is thicker, stronger, and more rigid. These sheets can be pasted together, or to paper sheets, to build up special thicknesses. Paperboard is made into a wide variety of items, including cartons and advertising displays. It's used for when you want relatively low structural integrity but a high quality of print surface. It can be coated in the same way as paper, and passed through sheet-fed presses for high-quality print finishes.

When dealing with differing types and styles of cardboard, the watchword is 'flute' - that is, the type or size of corrugation sandwiched between the two outer layers of cardboard. The larger the flute, the stronger the box. There are five classes of flute: F, E, C, B and A, with F being the finest and A the widest. It's also possible to specify weight of flute. The heavier, the stronger - and more expensive. For packaging, terms F and E are the most commonly used.

F flute is used for boxes that require something stronger than paperboard, such as soap-powder containers. The advantage of a fine flute is that you have a good surface to print onto. E flute is also a stronger alternative to paperboard, and good for die-cut designs. Like F flutes, it has a superior printing surface and works as software packaging or point-of-purchase boxes.

This is board that has a reflective metallic finish, and is often used for luxury packaging for the cosmetics and DVD/CD markets. It takes many print finishes, including foil, spot UV, creasing and die-cutting.

Polyethylene films are most commonly used for everyday plastic bags and film wrap. One advantage of PE is that it's an easy material to work with, easy to recycle and pretty stable.

Laminates are frequently used to change the property of PE. For example, A 15-micron polypropylene laminate might be used to achieve a high-quality gravure print finish.

Unlike PE, nylon is non-gas permeable, and in the food and pharmaceutical sectors - where you want to change or maintain the atmosphere inside the packaging - such film-barrier properties become important. The average bag of salad, for example, contains not air but nitrogen, which reduces the growth of bacteria and fungi.

The earliest PE barrier laminate was aluminium foil, but these are becoming less common because they're expensive and inflexible, and so prone to fatiguing. However, they're still widely used on ground-coffee bags to prevent odour seepage, and in the electronics components market.

These materials give a higher sheen than PEs and a better finish. They tend to be used when you want a thinner material and a higher quality print surface, such as the printed sleeves on plastic bottles of fizzy drink. These are heat-shrunk onto the bottles. They are printed using an offset method that takes into consideration the shrinkage.

These are PVC, APET and PETG, and are most often seen on shelves as meat trays, fruit punnets, and so on. Most tend to be PVC, which is environmentally unfriendly but is still specified by a lot of designers because it's easy to work with and cheap.

APET and PETG are often used for clear packaging like that shown below, and, unlike PVC, they don't become discoloured when irradiated. This makes them ideal for use in the food and pharmaceutical sectors, where produce often requires sterilisation. APET is cheaper than PETG, but PETG is used more often because it's easier to work with.

Clear-plastic blister packs are used in conjunction with a cardboard blister card to keep a product in full view for the customer to examine. They are durable, transparent, and tamper-proof. The blister packaging is attached to the blister card through a heat-sealing process.