Innovative Barrier Materials featured at PACK EXPO International 2006 will help extend shelf life and build brand loyalty.

Alcan's ClearShield™ high-barrier shrink bag for bone-in meats is a co-extrusion with outstanding puncture resistance, clarity, barrier and ease-of-use.

With hundreds of new products launched every week around the globe, building brand loyalty is challenging. Factors such as visually appealing packaging, convenience and price are all important and help consumers make decisions at point-of-purchase. But what turns a first-time buyer into a repeat purchaser? The attributes just mentioned will certainly have an influence, but product freshness also plays a critical role in brand success.
Brand owners seeking the latest film and rigid container technologies developed specifically to extend shelf life and enhance product freshness will find a multitude of options at PACK EXPO International 2006, being held at October 29 – November 2 at Chicago’s McCormick Place. PACK EXPO will showcase an array of packaging materials and containers as well as the latest developments in packaging machinery, exposing visitors to a large range of packaging capabilities.
The following is an overview of some of the most recent trends in barrier films and related packaging elements that represent a sampling of products that will be on view at the show this fall.  

Better barriers all around

Alcan's barrier film package for Sunkist Almond Accents also enhances shelf presence by supporting brilliant printing.

Ilene Gordon, president of Alcan Packaging Food Americas (Booth # E-8605) cites improved barrier films as one of the primary trends in flexible packaging. For instance, Alcan’s award-winning ClearShield™ high-barrier shrink bag for bone-in meats is a co-extrusion of polyethylene and polyamide that is oriented using a proprietary process. The combination produces a film with outstanding puncture resistance, clarity, barrier and ease-of-use for packaging bone-in meat products.
“Extending shelf life with better barriers and combining them with packaging more convenient for both the manufacturer and consumer is key,” she points out. “This has enabled flexible packaging – from standup pouches to retort packaging – to steadily grow in areas traditionally dominated by rigid formats.” Flexible packaging’s compatibility with a wide range of production processes, filling methods and handling, combined with its lighter weight and eye-catching printability, contribute to its increasing success with manufacturers, retailers and consumers, Gordon believes.      

Alternatives to foil

Aluminum foil has long been a reliable constituent of moisture barrier films. The aluminum foil itself has excellent barrier properties, blocking both moisture and gas transmission, and considered by many to be unmatched by plastic films to date. However, as pointed out by Eric Bartholomay, product development manager for Toray Plastics (America) Inc. (Booth # S-2941), foil tends to crease when flexed, as happens in the course of case packing and shelf stocking of pouches.
“Foil suffers from deadfold,” he says. “It creases with handling, and that leads to a less-than-attractive shelf presence. Creasing also can lead to pinholes in the thinner foil gauges that are common in food packaging. Once the foil has pinholes, its barrier is breached, and its effectiveness falls beneath that of film.”
Toray recently introduced a line of PC metallized propylene films that are specifically designed as replacements for foil laminates. Earlier this year, for instance, Unilever chose the new Torayfan® PC1 film to replace the traditional PPFP (paper-polyethylene-foil-polyethylene) packaging used for its popular Knorr and Lipton products. The choice followed a six-month trial that demonstrated that the new film delivered superior barrier protection that would enhance brand image while also reducing packaging costs.
Exxon Mobil Chemical Company (Booth # N-4533) has also developed film designed to replace foil laminates. The company’s Very High Barrier Metallyte™ film is a new generation of Exxon’s Metallyte OPP film that features enhanced barrier protection, making it an attractive replacement for aluminum foil. Metallyte 18XM383 provides among the best barrier properties available in uncoated metallized films and protects sensitive products against moisture and aroma loss or uptake, oxidation, ultraviolet light degradation, and flavor loss.
Metallyte XM383 provides an excellent water vapor transmission (WVTr) barrier, below 0.1g/m2/24h, which can extend product shelf life compared to other metallized films. In addition, the good oxygen barrier, below 7cm3/m2/24h, makes this film an excellent choice for modified atmosphere packaging (MAP), where maintaining inert gas conditions helps preserve foods sensitive to oxidation.

Toray's Torayfan® PC1 film gives Unilever's Knorr greater barrier stability and an aesthetically superior package while enjoying production savings.

“Some products,” says Ed Verkuilen, marketing manager of Rollprint Packaging Products, Inc. (Booth # E-7343) “need a protective barrier like that provided by aluminum foil or metallized polyester film composites, but can’t use either because the metal can potentially interfere with anti-theft devices currently used in retail packages and may cause similar problems with future technologies such as radio frequency identification (RFID) transmissions.” As RFID inspection and inventory use increases, this can become a significant problem. Rollprint’s alternative is ClearFoil®, a trademarked line of clear, high barrier films that do not contain any metal, as oxides of the aluminum actually provide the barrier properties.
The ClearFoil line of flexible, ultra-high barrier, transparent laminations now includes dozens of products that meet a wide range of barrier requirements and use numerous methods, including silicone oxide (SiOx) and aluminum oxide (Al2O3), to achieve the unique barrier requirements of individual customers in a variety of industries.
“People sometimes hear ‘aluminum’ and confuse the aluminum oxide coating process with metallization that utilizes vaporized aluminum, but it is not the same process,” Verkuilen points out. “Aluminum oxide deposition incorporates a very thin layer (only a few angstroms thick) of aluminum oxide which provides a clear film with excellent barrier properties without the use of metal.”        

Inside the barrier

When sensitive products are shipped over long distances in various conditions, even with an intact moisture barrier in place, it is impossible to confirm that the barrier is working and the product remains protected without some kind of sensor. Desiccare, Inc. (Booth # N-3530) manufactures a full line of Humidity Indicating Cards (HIC) that offer a low cost method of indicating humidity conditions for various types of barrier packaging, including MIL Spec (MIL-I-8835) applications. Cards range in size from 2 x 1.5 inches through 4.5 x 1.5 inches, depending on humidity capacity, and can be custom printed as needed.
The cards indicate humidity conditions within various types of barrier packaging, and are often used in conjunction with a desiccant that helps maintain low humidity. The indicator cards change color as humidity rises, changing gradually from blue to pink with each increase in moisture presence, allowing instant visual verification of in-package conditions and product integrity.      

Opening & reclosing

Rollprint Packaging's NutraSeal pouches, made with a ClearFoil® composite, are ideal for nutritional supplement packaging.

While barrier films are designed to protect product while the package they are part of is intact, eventually packages have to be opened. As consumers have demanded more and more convenience in packaging in recent years, that act of opening — and increasingly, reclosing — has grown to be something of a challenge to barrier packaging. How do you make a package protect against moisture and oxygen infiltration, yet also make it convenient to open?
“The film provides the barrier,” says Robert Hogan, director of international sales and marketing for ZIP-PAK, a division of Illinois Tool Works (Booth # S-1214). “In most cases, to gain the advantage of easy-opening convenience, a zipper is incorporated into the package but is not part of the barrier. The zipper is either inside the barrier, which has to be opened to access it, or the barrier ends below the zipper and a seal has to be broken to use the convenience feature.”
However, ZIP-PAK has developed a new zipper that incorporates a peal-seal in the zipper flange. If a packager wants the easy-open feature, and accessing the zipper necessitates the film being laser scored or perforated, the new peal-seal maintains the barrier that would be compromised by the score or perforation. The process of forming the package that incorporates the peal-seal zipper is also new, since the seal has to go around the ends of the zipper profile as well as below it.
“We deliberately engineered the peal-seal opening force to be relatively light,” adds Hogan. “No more than 2-3 pounds, enough to maintain the barrier but easy enough to open to offer consumers convenience. It also, incidentally, offers a tamper-evidence feature.”    

Seeing is believing

Clearly, there is a lot going on not only with barrier film development, but also with the packaging elements that work with barriers. These products, as well as many more innovative packaging materials and containers, will be featured at PACK EXPO International 2006, and are sure to garner significant attention.
For more information about PACK EXPO International 2006, visit