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In Packaging, Flexibility Scores Big

Flexible packaging is poised to increase 4.1% CAGR to 2016, creating a $71.3 billion marketplace, documents a recent report by Pira International. In the U.S., states the Flexible Packaging Association, flexible packaging generated 2011 sales of $25.4 billion, the second largest segment of the country’s $144 billion packaging arena.

Flexible packaging is replacing traditional packaging materials such as metal cans, glass, cartons and plastic, for a variety of reasons. Consumers—be they empty nesters, single-person households, or working parents—require food products with extended shelf lives, that are more convenient to use. Gen Y’ers are more likely to choose single-serve, snacks or grab-n-go foods rather than preparing a meal from scratch.

Also, flexible packaging’s reduced size saves in transportation costs, and its lighter weight is an asset for those looking to lower their carbon footprint. Its flexibility lends itself to a wider variety of shapes than metals or cartons, while giving brands more versatility in how they showcase their products.

Take a look at Equatic Solutions, makers of Horse Quencher, a cocktail designed to entice horses to drink water, which switched from a 3.5 pound bucket to a more environmentally-friendly 3.5-lb. pouch.

Manufactured by Eagle Flexible Packaging, Inc. in Batavia, Ill., the empty pouches ship flat and weigh less than an ounce, versus the former buckets that were cumbersome and weighed over 3 ounces each. Not only are the materials used in packaging reduced, but so too are the transportation resources before and after filling the pouches.

Print technologies in play

Flexible packaging can be manufactured using flexo, gravure, and digital printing machines.

The key factors that play into how a converter /printer will use a specific technology are primarily based on unit cost per linear meter. While digital printing methods capture a lot of headlines, in flexible packaging, gravure and flexo (offset is used for folding carton, but not flexible packaging) are the preferred methods for printing with longer print lengths of 10,000m or more. Print runs of 1,000-5,000m are the sweet spot for digital right now.

“The decision to use a particular print method is almost always based on the number of impressions being requested by the customer, and the print quality or type of ink needed to print the job,” says Mark Hill, VP and assistant director of research & development at INX International Ink Co. “For example, resistant inks for household cleaners are typically printed gravure due to more resistant polymers being available. Gravure for medium-to-high volume runs and flexo for low- to-medium volume runs are the norm. Cost is always a factor, so flexo and digital are chosen for low volume or one-time jobs and gravure is used for long repeat jobs.”

For high quality printing with extended wide web print runs that are repeated without customization, gravure is the choice, says Tony Renzi, vice president, product manager of Liquid Inks, North American Inks, Sun Chemical. “Flexo is another great option for long print runs with high quality printing. The flexo option tends to be at an overall lower cost to print due to the cost benefit of flexo plates versus gravure cylinders.

Narrow web converters growing in the flexible packaging arena are most comfortable with printing flexo for these applications, notes Cindy M Collins, Flexible Packaging Business Development Manager, Labels and Packaging Materials, Avery Dennison.

Over the last five years there has been a game-changing shift in flexography, says Mark Radogna, group product manager, professional imaging, Epson America. Epson, which develop packaging design and prototyping technology, has recently released the SurePress L-4033A digital label press. “In my opinion, the latest generation of flexo presses and plates yields image quality that is beyond beautiful, with line screens reaching 300 lpi.”

Gravure, explains Radogna, is a necessity when sustainability comes in to play. For brands like Proctor & Gamble or Johnson & Johnson, key factors are the ability to keep the packaging consistent, predictable, and repeatable for a decade or longer. Plus, they need to produce the package in runs of millions.

Flexo offers water-based inks (which are FDA compliant) that are well-suited for applications that are primarily surface printed and varnished. Says Collins. “Wide-web converters (being 20”+) would likely use gravure printing for these applications and apply an overlam for protection,” she explains. “ In theory, digital printing fits well into the short run; many SKUs and speed delivery required in the growing flexpack world of today, but the shortfalls lie in surface printing and the required good barrier for applications that require FDA compliance. The ink technology of digital limits applications for the narrow web converter, but there are solutions to make this technology work.”

Digital printing inroads

Narrow web and label opportunities have increased as digital press capabilities are being realized, and digital has the highest potential for growth in the packaging market, reports Peter Saunders, global sales & marketing manager, Sun Chemical. ” It is anticipated that there will be increased availability of capable equipment and higher adoption rates leading to significant growth in digital printing over the next five years,” says Saunders.

Perhaps not so much in flexible packaging, but certainly in labels and folding cartons.

“Folding cartons are likely the next available market in ‘packaging’ for digital. We recently launched the EtiJet LM UV low migration UV curing ink range for the digital label market which leads in that direction.”

While digital printing provides a great option for the variety of product SKUs going to market, roll-to-roll flexible packaging does require FDA compliant inks and varnishes for a variety of opportunities, and the high heat the ink is exposed to (300F+) are factors in using digital technology today.

Ken Kisner, president of INX Digital International, notes that while “digital is playing only a small part in printing onto flexible packaging, interest remains high. Digital printing is being used for special projects but has not reached the mainstream market. New, fixed array machinery is hitting the market with wider and wider arrays that allow digital technology to play a bigger role in the market. New print head technologies with higher native dpi and faster print capabilities are allowing for better penetration of digital technology.”

The HP Indigo is being used for some short runs that require treated substrates. INX Digital and a few other ink companies are currently testing Low Migration ink sets that they hope to market in 2013. These products will allow short run, mass customization and serialization, as well as test marketing.

“One of the hurdles is that Low Migration UV monomers, which have a high molecular weight, tend to have high viscosity levels,” says Kisner. “Ink jet requires extremely low viscosity in order to eject the small drop of ink out of very small orifices—the diameter is approximately 1-2 times the diameter of an average human hair. INX Digital is working directly with machinery manufacturers and print head suppliers to launch some new and exciting technologies for Low Migration inkjet applications.”

Drawing the lines

Deciding which print technology to use is dependent upon the application—food vs. personal care, variable printing required, how many SKUs, run size and any secondary operations that may be needed.

“In terms of technologies, I see digital gaining ground as speed and web width increases,” says Hill. “Those factors draw the line in the sand for flexible packaging. The cost to produce graphics for flexo or gravure printed jobs are the main drivers for traditional printing. Plates are still less expensive to produce than a gravure cylinder, and short run gravure is cost effective as long as the job involves repeat runs.”

Converters and printers typically draw the lines for which technology to use primarily based on the unit cost, which is dependent and print length and application. “Right now the sweet spot for digital is smaller runs, but there are other trends that go beyond the cost versus print length demand,” says Renzi. “Some of these market trends include personalization, short runs, differentiated packaging, and single use packaging, and all of these trends are conducive to digital print. That’s why there is an expectation for double digit growth in the next five years.”