Striving for innovation

Today’s flexible packaging lamination trends are firmly focused on several or all of these key factors, with the overriding objective of lowering production costs to meet consumer demand.  

One trend is film downgauging to reduce overall packaging weight. However, retaining the desired pack performance, such as stiffness, strength and barrier properties, creates another set of challenges.  

Tackling these issues head on, converters are incorporating specially-designed oriented films to enhance critical properties.  

Retort makes retail easy

While cans have been the solution for ready-to-eat food for a century or more, flexible retort pouches are providing a more user-friendly packaging alternative that suits today’s busier lifestyle.

Featuring laser scoring for easy tearing, spouts for easy pouring, or recloseable zippers for added convenience, they’re ideal for consumers of all ages.

Retort pouches are an attractive alternative to glass and metal containers. They can withstand retort processing temperatures up to 135ºC and have a high surface-to-volume ratio, resulting in lower processing time in the retort chamber – reducing the possibility of over-cooking, protecting natural flavours and saving energy.

Aesthetically speaking, utilising the gloss of the aluminium layer can create a metallic look, offering enhanced on-shelf visibility, while the pouch’s large display area provides additional space for bold graphics, branding messages and product information.

Cost reduction techniques

A decrease in the number of laminated layers by using innovative single-layer substrates not only reduces packaging weight and converting costs, but ultimately cuts the cost of packaging for the benefit of brand owners, retailers and consumers.

Another answer is to concentrate on film metallisation rather than the lamination of plastic films to aluminium – for example, a single layer of oriented metallised polyethylene (PE) sealant film can be used instead of laminating metallised BOPP to a PE sealant.

Highly-engineered lightweight ionomer films are puncture-resistant and also provide a seal that supports easy opening.

Coextrusion technologies entail the combination of two or more types of polymer in a single extrusion. This may minimise thickness without compromising performance, for instance oxygen and moisture barrier properties.

New auxiliary technologies are emerging in the form of flexible, clear higher-barrier coatings and specialised surface treatments such as atmospheric plasma. These processes could displace higher-cost coatings for barrier and print friendliness.

Machine-direction oriented (MDO) PE is an ideal replacement for biaxially-oriented PET (BOPET), it’s more cost-effective and sustainable than the BOPET, and has a lower density (its yield is almost 33,3% higher than BOPET at the same gauge).

By utilising MDO films instead of applying laser scoring to packaging for powdered drinks, converters can significantly reduce investment in capital equipment.

Short runs save time and money

Entrepreneurs always aim for ‘just in time’ production that results in lower inventory levels and cost. In the flexible packaging environment, this may be achieved by short production runs.

According to Comexi’s Albert Negre, short-run production means minimising changeover times. ‘At Comexi, we work with sleeve-type solventless coating heads so that changing the application width can be achieved in a matter of minutes. Shaftless unwinders and rewinders greatly help reduce changeover times while loading or unloading the machine,’ he says. ‘For high-productivity machines, the best solution in reel handling is to use automatic splices for both unwinder and rewinder.’

The following two factors primarily affect production speed, with a direct impact on effectiveness and profitability:

•  The competence of the machine manufacturer directly affects the length of film to be laminated over a certain period of time (ie m/min) and the machine’s downtime for repairs and maintenance. 

•  The competence of the chemistry manufacturer directly affects the usability and reliability of adhesive being utilised in the lamination process.

Supporting environmental sustainability

Many environmental and functional advances made by flexible packaging converters simply wouldn’t have been possible without the concomitant development of the basic building block of flexible packaging: adhesives.

Laminating adhesives have to keep pace with improvements in environmental and safety issues, while maintaining high performance standards.

Adhesive suppliers have developed high-performance adhesives that conform to biodegradability and compostability requirements (such as the EU’s EN13432 standard that stipulates that 90% of biodegradable packaging must be converted to CO2 within 180 days) and requirements on heavy metal content and the inhibition of natural plant growth.

A reduction in the number and thickness of laminated layers used in the production process not only reduces raw material consumption, but minimises a product’s carbon footprint.

A biodegradable film blend features a sealing layer that protects foods such as nuts, rice and lentils in the same way as a standard film, yet after use breaks down into water, CO2 and organic biomass.

Another option that meets increasing calls for environmentally-friendly packaging is a compostable biopolymer derived from corn starch. Such packs can be decorated using the latest eco-friendly water-based printing inks, containing less than 5% of volatile organic compounds compared to 65% in typical solvent-based inks. A zip-pack press-to-close system comprised of the same material as the rest of the pack allows consumers to open and reseal the pouch without compromising its compostability.

Constant innovation

Modified atmosphere packaging is increasingly used to enhance the shelf-life of many fresh food products. The true innovation is a natural substance added to the film’s contact layer.

An inventive technique that is enjoying exponential growth over the last couple of years is packaging that detects a change in the environment. An example is the ‘red dot’ that appears on the Debonairs pizza packaging that indicates temperature.

In summary, significant opportunities exist for flexible packaging converters as a result of the expected rise in demand for consumer goods in the years ahead. Many converters may choose to enter the market during this phase but profitability will always be reserved for those willing to strive for innovation.

Ed’s note: The March 2013 Issue of PACKAGiNG & Print Media will feature more on lamination trends, including the films, equipment and adhesives that are set to make an impact on flexible packaging processes in 2013.

About Polyfoil SA

Polyfoil SA is a printer and converter of flexible packaging materials. In addition, the Johannesburg-based company has formed a strategic alliance with the Gerosa Group in Spain to distribute Gerosa’s range of flexible films and laminations in South Africa.