Surlyn-Compatible Zipper Assures Meat Packer High Quality
The trend toward zipper resealable flexible packaging continues to pick up steam since customers prefer the convenience, and retailers believe it creates consumer demand. Recent research conducted by Promo Edge's Retail Research Center (Lansing, IL) revealed that a whopping 98% of retailers feel zippered packaging positively changed products and created stronger consumer demand. Also, 67% of consumers said zippered packaging is "very important" to "extremely important" in their purchase decision.
Zippered packaging has come a long way in the past decade, but until now premium meat companies have had to deal with leaker rates because zipper material was not compatible with films containing Dupont Suryln sealant packaging resins. Manufacturers wanting to offer zipper packaging were forced to either settle for a lower quality sealant such as ethylene vinyl acetate copolymer (EVA) or give up the zipper concept altogether.
Recently a partnership between Minigrip/Zip-Pak and Dupont Packaging and Industrial Polymers has helped alleviate this problem as Minigrip/Zip-Pak has introduced several configurations of zipper technologies that are compatible with Dupont Surlyn sealants. This new development enables users who employ a Surlyn sealant layer in their film structure to retain the sealing qualities of Surlyn when adding a resealable fastener to the package.
According to Minigrip/ZipPak's Robert E. Hogan, the adhesive layer that is coextruded with the zipper has been modified for compatibility with Surlyn. "Until now, users of Surlyn sealants had to change their film structure if they wanted to upgrade their package to consumer-preferred resealable packaging," says Hogan.
Dupont's Surlyn ionomer resins, known for their excellent seal integrity for packaging films, offer outstanding hot tack strength and high melt strength plus a very broad sealing range. This combination of characteristics makes Surlyn adept at reducing leakers, increasing packaging speeds, sealing through contaminants and improving efficiency.
Applications for Surlyn-compatible zippers include sliced meats, cereal and pet foods. The zippers can be run on thermoforming, transverse direction v/f/f/s and standup pouch equipment.
Sausage Application
Since Dupont Surlyn provides such advantages to meat manufacturers as good heat-sealing at a broad range of temperatures, hot tack and sealing through fats and oils, high clarity and abrasion resistance, companies had been reluctant to trade off the dependable packaging resin for a package that, though convenient, consisted of lesser quality resins.
However, with this new development IBP Foods Inc. (formerly Thorn Apple Valley) is now using Minigrip/Zip-Pak's new Surlyn-compatible zipper on a resealable package for its brand of skinless smoked sausages.
Thorn Apple Valley (Southfield, MI), a leading meat processor with an extensive product portfolio that includes five top-selling national branded products, wanted the best of both worlds. It sought the high-quality Surlyn resin along with a reclosability feature. The company had been using zipper packaging that typically included a linear zipper and polyethylene-based sealants, but the package structure was prone to leaker rates. Moreover, productivity was often impeded.
Thorn Apple Valley's desire to improve product quality while achieving productivity gains led to the launch of the partnership between packaging engineers from Minigrip/ZipPak and the Dupont technical team to develop zipper packaging that would be compatible with Dupont Surlyn. Along with film supplier American National Can, the four companies worked together to identify issues in order to improve the quality of the package integrity.
The new resealable zipper that resulted uses Dupont Nucrel acid copolymer resin and polyethylene. The coextruded zipper bonds with Dupont Surlyn films to produce exceptional seal integrity in the package and in the zipper-to-film structure. This has resulted in reduced leaker rates as well as increased line speeds, though Thorn Apple Valley would not reveal actual production numbers. The meat packer is using Minigrip/ZipPak's model 226 zipper with grip strips, which features Minigrip's patented red colored line on flange feature, on resealable packaging for six different flavors of the Thorn Apple Valley brand of skinless smoked sausages.
According to Ray Freedman, VP of marketing at Thorn Apple Valley, the new Surlyn-compatible zipper has led to improved package integrity. "With the new zipper we've gained quality improvement in the product as well as productivity benefits," says Freedman. "Our goal was to improve the quality of the product integrity. We've done that with no increase in price to the consumer. The response to the packaging change has been very positive."
For more information:
Minigrip/ZipPak, Tel: 800-488-6973.
Dupont Packaging & Industrial Polymers, Tel: 800-4DU-PACK.
Edited by Bill Noone