By now, most paper bag users know that there are two different basic types of construction available: 3ply and 2ply
. Everyone may not know the benefits and challenges of each, and the differences in the paper used (which is why we offer both.) The information below highlights the main differences between the two:
|Regular Kraft Paper
(2 ply bags)
- Stiff/ low stretch / high tensile strength
- Requires larger perforations and/or under valve perforations for proper air release
- 15 second paper (Takes 15 seconds for air to penetrate each layer)
- AKA Flat Kraft or Natural Kraft
- Requires 3 plies
- Comes from domestic trees in the Southern U.S.
- Flexible / stronger/ 8% more stretch
- Breaths on its own / Perforations are micro or not required
- 5 second paper (takes 5 seconds for air to penetrate each layer)
- AKA Semi-Extensible
- Only requires 2 plies
- Comes from hearty trees in cold weather areas
In summary, Regular Kraft and High-Performance paper tend to work well for valve bags, although high performance paper is stronger and stretches more – making it less likely to break if dropped. Regular Kraft paper works slightly better if the bags are hand spouted because the paper is stiffer, making it a little easier to open the valves when using only one hand. For open mouth bags (SOM or PBOM), most applications work better with Regular Kraft paper due to the stiffness. High-Performance paper is used by some companies for open mouth applications, depending on whether the filling equipment is automated or manual.
If you have any more questions, or would like to request samples to compare the types of bags, reach out to our team at Global-Pak.