In a successful case of open innovation, snack food giant Mondelēz Intl. has partnered with Battelle, the world’s largest nonprofit research and development organization, to develop new packaging reclosure as an economical replacement to zippers and other reseal technologies. Called Low Tack Adhesive (LTA), the product only sticks to itself when simply pressed together but with high enough bond strength to provide a secure yet easy-open reclose feature.
Developed for snack food packaging, LTA has far-reaching applications for dry goods—cereal, for example. Consumers have been asking for easy resealing for bag-in-box cereal packaging for decades. Because LTA sticks to itself and nothing else, packages might be less messy without the product inside clogging or interfering with the reclosure feature.
One little hitch, though, on immediately using it for foods. Low Tack Adhesive has not received food-contact regulatory clearance yet. Mondelēz and Battelle are working diligently to make that a reality. But LTA can be used now as a reclose device on non-food items as diverse as wet wipes, detergents, trash bags, makeup and other personal care products.
According to the companies, LTA is cost effective to manufacture and apply. The adhesive is applied to a variety of packaging films using conventional printing and coating technologies. It is then ultra-violet (UV) cured. Films with LTA applied can be run on existing packaging machines with little to no modifications and at existing line speeds.
Stu Stein, director of open innovation at Mondelēz Intl., and Cindy Conner, senior market manager in Consumer, Industrial & Medical Products at Battelle, give specific details in a Packaging Digest exclusive.
Why did Mondelēz work on this specific packaging development?
Stein: We wanted to come up with a “new to the world” packaging technology that had features beyond what was currently available. We helped come up with Low Tack Adhesive because it can provide secure containment which reduces the chances of spilling and extends product freshness. It can add reclose functionality to packages without making costly modifications to packaging lines. And unlike plastic zipper systems, which require costly packaging line modifications or retro-fits, Low Tack Adhesive is already pattern-coated on the film when it arrives at your plant. In most cases it can be implemented with only a simple seal jaw modification.
How will Mondelēz be using the LTA?
Stein: Packaging is both the first and last thing people encounter with a product, so if we can offer a better experience for consumers that competitors don’t offer though a technology like Low Tack Adhesive, we’re providing unique value which helps us win in the marketplace. We’re looking at opportunities to use Low Tack Adhesive for our own applications at Mondelēz Intl., and we’re also interested in licensing for applications outside of our markets. We unfortunately can’t share more details of our commercialization plans right now because we don’t want to tip our hand. Also, to be clear, as of right now, full compliance with food packaging regulations has not yet been established for Low Tack Adhesive, but we and Battelle are working toward that goal.
How well does the LTA release from itself? What kind of force is needed to unseal a resealed package? Do you have some stats on that?
Conner: The LTA was optimized for snack packaging application with a target initial opening force of 300 grams per linear inch and a durable strength peel after repeated opening and closing of greater than 200 grams per linear inch. That force is somewhat equal to pulling an easy peel pressure-sensitive adhesive, such as painters tape or standard juice bottle foil seals. The strength of the adhesive can be tailored, up or down, dependent upon need. These were the requirements determined from human factor studies at the beginning of the program.
You say it withstands the test of repeated cycles of opening and reclosing. What number or range can you put to that? What number did you test up to?
Conner: Testing was exhaustive and included long-term aging studies, as well as cyclic peel testing. This adhesive can withstand more than 20 cycles without loss of durable peel strength.
You say LTA can be applied cost effectively in typical printing/coating operations. Again, what specific number can you put to that? At a 10% upcharge to no reclosure feature? At 50% less the cost of a zipper?
Conner: We cannot provide a specific number at this time. However, this adhesive removes several manufacturing steps from the standard mechanical fastener systems. Raw material costs are less than those used in the manufacture of the mechanical fastener, and costs associated with incorporation into the package are much cheaper.
As this is a “reclose” feature, give us an example of how the LTA will be incorporated into the structure/format of the package and how a package will be opened initially.
Conner: There are many versions of design for incorporating this adhesive. For instance, the LTA adhesive may not be engaged at initial packaging seal and only used after the initial opening of the package. It would be placed on the interior of the product package and sealed with low pressure applied by thumb and finger. Additionally, there are many markets and products where this adhesive has application, including secondary storage bags, pet food, diapers, tapes and so on.
How does the application of LTA on packaging film impact (good or bad) how that film runs on a form-fill-seal machine, for example? Any anticipated slowdowns on the packaging line? Why or why not?
Conner: We anticipate no slow down to packaging lines. Our trial runs at commercial scale have demonstrated the ability to meet standard run times of packages without this adhesive. Eliminating the secondary step of applying a fastener ultimately provides for faster overall production times.
What was Mondelēz’s contribution to the development of LTA?
Stein: Mondelēz’s contribution included defining the critical performance criteria, developing processes for applying the coating to packaging films at high speeds and conducting trials to confirm acceptable performance on the converting and packaging lines.
Thanks to open innovation, we’ve been able to get more people involved to come up with better solutions, more scale and faster speed to market than if we did everything ourselves—which is good for both our business and our partners. We’ve been most active in the past few years on this particular project, focusing on applying the technology to manufacturing and how it would work in real-world applications. We probably wouldn’t have undertaken it if we had to do it all ourselves. We were able to provide unique perspective from the food industry on potential applications in that space. Together, we’ve collaborated on the know-how and the scale to make a great idea even bigger!