Anatomy of a Multiwall Bag

Posted by Alan NeSmith on Jun 25, 2013 7:30:00 AM

Untitled_design-1Multiwall paper bags are often used as shipping and storage containers for bulk materials. In many cases, design and production artists can create and adapt multiwall bags that work for your specific needs, from a utility approach that simply identifies your product, to the more difficult task of grabbing the consumer’s attention at the point of sale.  There are two basic designs of bags:  open mouth bags and valve bags, and variations thereof.

Open Mouth Bags

An open mouth bag is a tube of paper plies with the bottom end sealed. The bag is filled through the open mouth and then closed by stitching, adhesive, or tape.


  • Open bag
  • Re-opening devices may be applied so that product remains protected for a longer period of time by the end user
  • Typically bleached or natural paper
  • Varying weights
  • Optional coatings- for glossy effect or to improve frictional characteristics
  • Optional protective barriers/liner

Common Uses:

  • Food
  • Pet Food, pet care
  • Animal feed, seed
  • Chemicals, pharmaceuticals
  • Minerals

Valve Bags

Valve bags have both ends closed (pasted) and are filled through a valve.


  • Closed bag
  • Designed for high speed filling through a valve on spout packers
  • Biggest benefit is top performance wherever high speed filling processes are used, as well as protection properties
  • Optional liners where moisture protection is needed
  • Bleached or natural paper

Common Uses:

  • Cement bags
  • Building materials such as plaster and dry mortar
  • Food
  • Pet food
  • Animal feed, seeds
  • Chemicals, minerals
  • Detergents, granulates

Multiwall bags are made up of at least several layers of paper products to include inner ply and a printed external layer.  Some have a polyethylene foil or polyethylene coated paper layer in between as a vapor/grease repellant protective barrier. 

At Oren, we supply the “accessories” that go into making a multiwall bag. Contact us to find out more about Oren’s components for creating multiwall bags.

Tags: Paper Converting