Packaging

Sustained strong demand for lightweight packages with high functionality

Thursday 22. September 2016 - Maximum product protection with the minimum input of materials, decorative design to stimulate purchase, and resource efficiency in production, storage and transport - the requirements are very diverse. K 2016 will present innovations in design, production and applications for a huge variety of packaging materials and production methods. This article examines the trends in packaging and takes a brief look ahead to the highlights of actual exhibits at the fair.

“The packaging of tomorrow is smart and geared to specific target groups and convenience.” That is what was written five years ago in the packaging sector report of IG Metall and IG Bergbau, Chemie, Energie (trade unions for the metalworking, mining, chemical and energy industries). And nothing of this will change in the coming years either. For in its most recent report “The Future of Global Packaging to 2020”, Smithers Pira in Leatherhead, UK, has again identified re-closable convenience packages, extended shelf life, easy-open packages and on-the-go packages as the outstanding trend themes of a sector that continues to show overall growth. The world market will grow, Smithers Pira claims, by 3.5% from USD 839 billion in 2015 to USD 998 billion in 2020. This momentum in the packaging market is being driven principally by Asia but also by Western and Eastern Europe, with growth being stimulated among other things by advancing urbanisation and the subject of sustainability.

Packages are required in almost all sectors. While usually protecting the product and facilitating storage and transport, they can also help to differentiate products at the point of sale and thus constitute a selling point. In the past, packaging solutions have been consistently brought into line with market requirements and customer needs. Examples of this are distinctive crystal-clear bottles for household, and body and hair care products, sparkling high-quality plastic flacons for perfumes, special deep-drawn trays for electronics articles providing protection from electrostatic discharge and designed for product insertion by robot, and foldable transport boxes and stretch films for securing loads in trucks, to name but a few.

The food industry enjoys high attention and market importance within the packaging sector. In Europe countries alone, some 60% of foods still spoil, and this figure could be reduced significantly with appropriate packaging. What is more, according to a publication by packaging market researchers Gesellschaft für Verpackungsmarktforschung (GVM), product protection is always also climate protection, which in a turn is a subject of social relevance. The carbon footprint for the production of a new food to replace one lost due to inadequate product protection is usually much larger than that for the production of a suitable package that prevents spoilage.

The packaging sector continues to boom – and with it the requirements it has to meet, its possibilities and the innovative solutions. Its sheer diversity cannot be covered exhaustively in a single article, so only a selection of topics and examples have been picked out in the following without any claim to being comprehensive.

One subject repeatedly mentioned in connection with plastics packaging is health, although many different aspects are again concerned here. It goes without saying that each protective packaging benefits consumer health by shielding the food from external influences of all kinds. In the beverages sector in particular, there is a trend towards adding health-promoting substances to drinks that need special protection. Examples of this are fruit juices with high vitamin contents and sports and fitness drinks with special dietary supplements. KHS Plasmax GmbH in Hamburg has developed its Plasmax technology so that these drinks stay fresh in bottles for a long time. In a low-pressure plasma process, a roughly 50 nm layer of pure silicon oxide, i.e. glass, is deposited on the inner wall of a PET bottle. The drink thus keeps for longer, is protected from external influences and its vitamins and additives are prevented from escaping. Unlike the rival multi-layer bottle, the Plasmax technology is slightly more elaborate, but the cost of materials per bottle at about 1 cent per bottle is significantly lower. The main benefit of the Plasmax process is that the bottle can be fully recycled.

Another trend in the beverages sector is towards healthy drinks containing chunks, e.g. water with chunks of Aloe vera and milk and yoghurt drinks with fruit chunks. This calls not only for the matching bottle geometries, but also for bottling technologies capable of cleanly and precisely metering solid particles. As one of several specialist machine manufacturers in this area, Krones AG in Neutraubling is offering under its Dosaflex label special metering systems for lumpy products up to a size of 3x3x3 mm with a metering accuracy of ±0.3%. And on the subject of milk and yoghurt drinks, there is a distinct trend here to an expanding product spectrum. However, since dairy-based drinks have an only limited shelf life, Holland Colors NV in Apeldoorn, Netherlands, is presenting at K 2016 its new Holcomer III solid additive that permits the production of PET monoloyer packaging solutions for UHT milk as it yields 100% protection from UV radiation and up to 99% protection from visible light. The obvious advantage of this solution is its monolayer structure which lends itself better to recycling than the multi-layer equivalent.
Light weight as a perennial theme
The weight of each package solution continues to be important. A great deal has happened in this area in the last few years. The ideas and savings potentials are many and varied: the omission of package outers, flexible rather than rigid or semi-rigid packages, new designs and the reduction in wall thicknesses. From 1991 to 2013, packages thus became 25% lighter overall. In 2013 alone, 1 million tonnes of plastics was saved worldwide as a result of weight reduction, despite the growing expectations on functionality. And, taking PET again as an example, not only have the wall thicknesses been reduced, but the base design has also been optimised. The new thread design alone saves 2 g of plastic per bottle. To optimise the bottle base, Creative Packaging Solutions Ltd. in Balcova-Izmir, Turkey, has developed its Mint-Tec process in which, after creation of the preform, a ram extends into the latter – without touching the neck – and gives the base its desired shape.
Recyclable design from the outset
The trends cited for beverages as examples also apply to practically all other areas of the food sector. Weight reduction is always top of the wish list. This is of course because weight reduction is associated with savings of material and reduced cost. However, this is not the only reason. Growing in prominence, as it is demanded increasingly by legislators as well as by consumers, is resource conservation. Closely associated with this is the scope for package recycling. In Germany today, almost all household packages are reutilised, with more than half (56%) being recycled rather than being incinerated for the energy content. About 20 years ago, the figure was only 3%. In the case of PET bottles, the rate is much better, with 98% undergoing material recovery and being returned to the production cycle. Consequently, each new bottle produced today contains about 25% regranulate.

The reutilisation rates for packaging wastes could be upped still further if packages were given recyclable designs from the outset. As a polyolefin processor, Dr Michael Scriba, Managing Director of mtm plastics GmbH in Niedergebra, is acutely aware of the problem areas. In his view, pure-grade plastics should be used wherever possible, and not paper-plastics composites nor too heavily pigmented or chalk-filled polyolefins. In addition, PET should be preferably used for bottles rather than for deep-drawn trays, to name just a few of the preconditions for improved package recyclability.
Films have been becoming thinner and more functional for years

At over 40%, films represent the most frequently encountered plastics packaging, being used mainly for foods but also, for example, in bubble wrap or stretch films for protecting goods. In the film products area, there is also a marked trend towards increasingly thin and functional solutions. Functionality can be achieved with suitable additives, although most commonly with multi-layering. The demand for more and more layers has thus culminated in so-called nano-layer arrangements of 33 layers and more. Today, 3- and 5-layer films are standard products, not least so that less expensive materials can be used for the middle layer.

Barrier films are usually composed of 7 and more layers. This year at K 2016, Hosokawa Alpine AG in Augsburg is presenting an 11-layer film-blowing line for high-barrier films which also has an extra-compact design. Thanks to functional layers, multi-layer films usually have the advantage of being less thick than mono-products. While retaining its functionality, the film’s thickness can also be reduced by stretching. Especially for this, Reifenhäuser Blown Film in Troisdorf will be showing at the trade fair the Evolution Ultra Stretch unit that is installed right on the blowing tower. Thanks to the stretch unit, compression bag films for nappies can be produced 50 rather than 70 µm thick and silage stretch films with an unchanged range of properties 19 rather than 25 µm thick – a thickness reduction of 30%.
Efficiency a big talking point in injection moulding

In the production of injection-moulded packaging materials, thickness reduction and savings of material are also big talking points as well as optimising cycle time and boosting efficiency. This will be very evident at this year’s K when Netstal Maschinen AG from Näfels in Switzerland, for example, is exhibiting a high-performance an injection moulding machine with an electric welding unit that outputs over 43,000 round lids per hour with a weight of 7 g per item. In-mould labelling (IML) has long been one of the well-known decoration methods for injection mouldings. Sumitomo (SHI) Demag Plastics Machinery GmbH in Schwaig is exhibiting its El-Exis SP 200 – probably the fastest machine for the production of decorated cups with a cycle time of less than 2 s.

A process for making injection-moulded packaging items even thinner and lighter is injection compression moulding (ICM), which is becoming increasingly established in the industry. This process differs from conventional injection moulding in that shrinkage is compensated for without injecting additional material in the holding-pressure phase. Instead, the ICM process makes use of a compression cycle, i.e. displacement within the mould. This makes savings of material of up to 20% possible. At the fair, Netstal will be demonstrating the production of a PP margarine package weighing just 10.7 g.
Industry demonstrates immense innovative powers

As already mentioned, it is impossible to cover all the trends and news in a single article, but here are a few all the same:

It is important not to overlook the growing interest in the production of food packages with biodegradable plastics – new products are coming increasingly onto the market here.
Direct printing is a process in which plastic packages as well as their lids can be printed directly without a sleeve or label. In digital printing, the printed image can be modified and applied directly at the press of a button – so individualisation is writ large in this area. Each item could be given its own print.
At K 2016, several injection moulding machine manufacturers will be showing an application for injection blow moulding, a technology with which an injection moulded preform is blown directly in a multi-station mould and, if desired, overmoulded as well. Highly attractive package solutions can be produced in this way.
For injection-moulded and deep-drawn packaging items, the ibt process of Cavonic GmbH in Engen is a way of applying a glass-like layer in the low-pressure plasma process and thus improving the shelf life of foods such as fruit spreads, baby food and dairy products in transparent mono trays.
With the appropriate machine equipment, deep-drawn IML trays can be more cost-effectively manufactured than injection-moulded ones. Illig Maschinenbau GmbH & Co. KG in Heilbronn builds thermoforming systems capable of producing lighter trays faster and thus generating production costs of EUR 43.80 for 1,000 units compared to EUR 51.60 for the same trays manufactured by IML injection moulding.

Those interested in packaging materials can expect just as many new ideas at K 2016 in October as the packaging industry at interpack 2017 six months later.