What material is a potato chip bag?

Potato chip bags are typically made from multi-layer plastic film. Here's a breakdown of the layers and why they're used:

* Outer layer: This is usually a polypropylene (PP) layer. It's strong, durable, and gives the bag its color and print.

* Middle layer: This layer is often polyethylene (PE). It provides barrier properties, protecting the chips from moisture and oxygen.

* Inner layer: This layer is typically polyethylene terephthalate (PET) or surlyn. It's a very thin layer that creates a barrier against grease and odors, keeping the chips fresh and crisp.

These layers are bonded together to form a single, flexible bag that keeps the chips fresh and protected.