The role of packaging and the environment has been a hot topic for over twenty years. Over that time the emphasis has shifted somewhat, from the initial concerns regarding landfill to today's emphasis on reducing co2 emissions. Ultimately, it is about conserving precious resources so that they can be enjoyed by future generations.
No discussion regarding packaging and waste can escape a few facts and figures. According to Waste Online, the UK generates 434 million tonnes of waste annually. Some 30 million tonnes is household waste of which 7% consists of plastic. The plastic within household waste splits down into 4% dense plastics and 3% plastic films. About 8% of plastic is currently recycled and 7% goes to incineration. Therefore, a total of 765,000 tonnes goes into landfill. To put this into comparison, 2%, or 600,000 tonnes of waste are used, disposable nappies or diapers.
It is worth answering the question why we package products in the first place. To protect the product, to increase the shelf life and to ensure the integrity of the product contained within are all important considerations. A good argument can even be put for wrapping cucumbers, whereby according to Sarah Miloudi in her article Unwrapping the Case for Packaging shelf life can be extended by up to 4 times.
JoAnn R. Hines, a.k.a 'the Packaging Diva' makes the point in her blog about the Tylenol contamination scare in the early eighties. Very few people today realise that this post production contamination disaster spawned the entire shrink sleeve and tamper evident labelling industry because inadequate packaging was literally putting people's lives at risk.
However, products are also packaged for marketing reasons. I agree with Jeffri L. Epps who, in his presentation Packaging should be a Forethought for your Product, argues that 'The Package is the Product'. He reasons that the presentation of a product is the key reason for its success or failure. There is little point in going to the expense and effort of developing a new product and bringing it to market unless it is given the best chance of success by being appropriately packaged.
Compared to the total household waste produced plastic films contribute relatively little to landfill. However, the government has produced the 'Waste hierarchy' which seeks to reduce the impact of waste. Starting in order of greatest importance, it is necessary to reduce, reuse, recover (recycle, compost, recover energy) as much waste as possible before the final option, disposal.
Energy efficiency of the materials and machinery used is also an important consideration. All packaging materials consume energy in their manufacture and all machinery consumes power during the packaging process. To truly provide environmentally friendly packaging both materials and machinery should consume as little as possible.
So the trick is to provide packaging that can be reduced, can be re-useable or can be recovered whilst at the same time providing a great marketing platform, protects and enhances the product but does not use large amounts of energy during the packaging process. I believe that over wrapping manages to satisfy most of those criteria.
Reduction in material
If the purpose of the wrap is solely to protect the product inside, overwrapping film can be as thin as 17 micron. Although this is not recommended for high speed wrapping, because of the positive film transport system used by Marden Edwards machines it is quite possible to run at speeds up to 60 wraps per minute. Indeed, one of Marden Edwards customers in Pakistan is doing just this with their range of biscuits.
One of the most important roles for overwrapping in terms of a reduction in material is to replace cartons with film. For example, a retail multipack need not be put into a heavy card or plastic carton but can simply be grouped together using an overwrap. The article Reducing the cost of Cigarette Packaging discusses these ideas in greater detail with reference to the tobacco industry.
However, if the purpose of the wrap is solely to prevent the carton or collation from being opened, then a band wrap is all that is required. Again, because of the positive film transport system, Marden Edwards overwrappers are fully capable of wrapping with only a band of film, as narrow as 50mm. The band itself is tightened on the machine and for extra security can be glued to the wrapped box to further enhance security. For example, Marden Edwards has recently shipped a machine for wrapping a collation of six hang tab boxes. The Marden Edwards machines collates the hang tab boxes to form a perfect rectangle which is the band wrapped, solely for distribution purposes.
Often the carton enclosing the product being overwrapped can be reduced in strength, weight and hence material since the overwrap gives the finished product strength. This lightweighting can go so far as removing the lid of the carton altogether and creating a tray. This is especially popular in the chewing gum and sweets industry where the cardboard tray then goes on to form the shelf ready packaging for display purposes in the retailer. This is illustrated by a machine that Marden Edwards has recently shipped to a Nigerian customer.
It is not possible to re-use overwrap film. So that it can be seen to be tamper evident, once the film is torn then its job is done. The actual weight of an overwrap is small, only a couple of grammes at most. Even if the film is removed carefully it is not possible for it to contain another product.
However, it is possible for the film to have two functions. By utilising an extra tear tape strip to provide extra rigidity for the wrap, it is possible to use the film overwrap for a collation of products as a shelf ready tray. Using one tear tape the top of the film is removed. The products then sit in the lower half, the tray, which then acts as shelf ready packaging as the products are removed and sold. This practice is most common for pharmaceutical blister packed products.
There are three methods of recovery of over wrapping film combustion, recycling and composting. Which ever method is chosen depends very much on which type of over wrapping film is used. As explained in the article overwrapping films come full circle it can be seen that a wide variety of films can be used for overwrapping, which include Polyproplylene (oil based), Polyethylene (oil based), PVC (oil based), Cellophane (wood based), paper (wood!) and Biophan (made from corn starch). Depending on which has been used determines what the most appropriate recovery method is.
All films burn well and will assist combustion if waste is burnt in an incinerator. Incinerating waste has the advantage of recovering energy by producing electricity and dramatically reduces the amount of land fill. The question mark still hanging over waste incineration is the possibility of harmful contaminants being released into the environment.
Both polypropylene and polyethylene can be recycled. Mixed domestic recycled plastic waste can be reused as a feedstock additive for other types of low grade plastic.
For the organic based products there is another alternative - composting. Although the temperature and time conditions for composting to occur are quite strict for corn starch based films, it is not the case for cellophane which breaks down in normal landfill. The article, 'Can Marden Edwards machines use environmentally friendly BOPP film' discusses in more detail the process of composting of these films.
Finally, if none of the above methods have worked, the film will go to waste as part of landfill. The good news is that the amount of film used per pack is very low and hence all plastic films used only contribute to less than 3% of domestic waste going to landfill.
The Use of Overwrapping for Marketing purposes
Over wrapping is often perceived as using solely a clear film for the purposes of protection and presentation of the product contained within. However, the development of new opaque laminated films has meant that printed film can fully enclose the product without be able to see the product contained within. Using this kind of printed film can substantially help reduce waste by replacing printed cartons.
For the multipacking of retail products, printed film has the ability of obscuring individual pack bar codes and displaying the bar code belonging to the multipack. For further flexibility the new bar code and the obscuring of the old bar codes can be printed on the film as the over wrapping machine is running.
When looking at the amount of energy consumed it is necessary to investigate the amount of power that the wrapping machine uses, the amount of energy then required by air conditioning units as well as the amount of energy consumed in the production of the wrapping material.
Over wrappers, flow wrappers, vertical form fill and seal machines all use small amounts of energy when compared to shrink wrapping machines. Whereas the former machines all need heat solely to seal the film locally, shrinkwrapping machinery needs vast amounts of energy, up to 60KW, to shrink the film around the product. Although advances in shrink tunnel insulation have helped, energy consumption by shrink wrapping machines is high.
It is not easy to say which type of wrapping film uses the least amount of energy to produce. It could be argued that the oil based materials are the cheapest as they are bi-products of petrol production and hence the infrastructure for production is already in place. Both cellophane and Biophan come from natural products which require a large amount of processing to produce. The Friends of the Earth organisation argues that rather than growing crops for fuel or packaging it is environmentally better to grow food to feed the planet.
Given that packaging is an essential method of protecting goods and increasing their desirability, it can be demonstrated that overwrapping is environmentally friendly with its ability to reduce packaging material, be made from environmentally friendly materials and use a small amount of energy during the packaging process.
Jeremy Marden 30.07.07
Marden Edwards Limited