Zipper Delamination (Zipper Tearing Off)

Sometimes, when a customer pulls the zipper to open a bag, the zipper stays closed, but the film rips away from the zipper base. This is a heat-sealing issue. The heat seal bar that attaches the zipper to the bag didn't get hot enough or apply enough pressure to fuse the materials, or the materials (eg, PE zipper vs. PP inner layer) aren't compatible.

This should be a heat-sealing issue, in most cases, the sealiing temperature fluctuates in the bag-making process and make the sealing unstable.

Bruce 发表于 2025-12-16 18:42
This should be a heat-sealing issue, in most cases, the sealiing temperature fluctuates in the bag-m ...

Alright, during the sealing process, do we need to check the bag weight? For example, if a coffee product is 500g, do we need to keep the sealing temperature stable according to that weight?

KhiljiMusab 发表于 2025-12-16 21:13
Alright, during the sealing process, do we need to check the bag weight? For example, if a coffee  ...

There is a standard for sealing strength; we must make sure the zipper is sealed very well, regardless of the weight of the product.