Serration type for custom polybags: depends on end use

9-1-16

Serrations on custom polybags (perforation word is used interchangeably with serration) allow entrance into the bag once the bag is closed.   Serrations take one of two forms depending on end use:

•  Soft serration — Soft serration is defined as a serration that is very easy to tear open.  Soft serration is used when the weight of the contents does not fall on the serration itself or when the packaged item is very light.
  • Examples
    • Tamper evident zipper bags.  Used with tamper evident zipper bags where the serration is above the zipper.  Item is bottom loaded and sealed into the bag.   The packaged item is below the zipper and thus does not interact with the serration above the zipper.  The end user will access the item by tearing the serration above the zipper and opening the zipper to reveal the enclosed product.  The bag is referred to as “tamper evident” as the only means to enter the bag is to tear the serration or destroy the bag.   Most pita bread is packed in tamper evident ziplocks.
    • Lightweight items such as cotton balls.   Cotton balls do not affect the integrity of the serration through direct contact due to lightweight.
    • Staple packs and Bag on rolls.  Staple pack bags and Bag on rolls will generally have a soft serration to allow the bag to be easily ripped away from the group or roll.
• Hard Serration — Hard serration is defined as a serration that can withstand the weight of the product on the serration itself while retaining functionality by the end user.
  • Examples
    • Mailing bags.   Mailers that require a serration need to have a “hard serration” to allow the serration to withstand the rigors of transit without breaking but still be functional at the time of opening.
    • Heavier contents like an ice cream sandwich.  At first glance, an ice cream sandwich would not seem heavy but the weight of the sandwich could affect the integrity on a easy to rip serration during packing and transit.   Thus, a hard serration is used to ensure the serration stays in tact until end use.

Serrations can be made hard or soft by adjusting the on-machine serration pressure and changing the serration wheel (larger gap between perfs for harder serrations).

The picture shows a serration dieline with a horizontal serrations 1/2″ off the bottom of the bag.

Samples available upon request.

Hope this helps get the serration you need for your application!