Creating a film that offers brains and brawn can be a challenge – and this is a challenge that Berry Plastics recently faced with one of its customers, a Fortune 500 manufacturer of consumer food products.

The problem? The food product in question is in the cracker family, yet its shape has hard points. When the product is dropped through the filling tube on a VFFS machine, these hard points have a tendency to puncture the film and protrude through the bag.

“These points, in effect, acted like a spear point with the force of the food drop behind it,” explains Paul Wolak, senior technical director, Berry Plastics.

Hence, the challenge was to dramatically improve the strength and toughness of the bag-in-box liner so that this snack product would survive intact during the forming and filling process. The easy solution to this challenge would be to increase the thickness of the film, thereby increasing its toughness. However, thicker film is not always the answer.

“Thicker films can slow down packaging machines because it takes longer to drive heat through the thicker film to make a heat seal,” Wolak says. “In addition, pushing that bag into a box becomes more difficult since the bag is stiffer and more difficult to deform as it slides into the box.”

The customer knew the importance of providing ultimate freshness by ensuring the packages were hermetic and did not contain any punctures or tears from the filling process. This was particularly difficult given that the snack shape and fill weight were causing punctures. The customer had to solve the problem in a short time frame and could not continue with its current packaging system. Additionally, a barrier to both moisture and flavor were required, as well as a significant improvement in toughness to preserve shelf life.

The team at Berry Plastics utilized multi-layer, co-extrusion technology, coupled with precise materials management as keys to enhancing the performance for this packaging. Performance polymers were incorporated into specific layers in the film to maximize film strength and barrier properties, all while maintaining processing and manufacturing requirements. 

This new liner delivered excellent moisture barrier, equivalent flavor barrier, easy opening seals and the toughness and strength to survive the demanding application for this difficult-to-package snack. The film, developed with extreme toughness, solved the puncture and pinhole issues for the customer, protecting shelf life, product integrity and brand reputation.

The innovative approach to solving the problem created a film, XTBarrier 7B4X6-10005LN, that had novel performance. Berry Plastics now has a patent pending on the solution.


Berry Plastics Corp.
(812) 424-2904