3-Side-Seal Bag
Also called: three-side-seal pouch, 3-side sealed flat bag
A 3-side-seal bag is a flat flexible pouch sealed on three edges — typically both sides and the bottom — with the top edge left open for manual or premade-pouch-machine filling, then closed with a final top seal after the product is loaded. The format bridges the gap between fully-open flat bags and hermetically-sealed 4-side-seal pouches, offering a balance of convenience, fill flexibility, and barrier protection.
3-side-seal pouches are commonly used for sample-size portions, single-serve condiments, desiccant sachets, and any application where the product is best loaded separately from the pouch-forming step. They're also a popular format for short-run contract packaging where pre-made pouches are purchased from a converter and filled on relatively simple sealing equipment.
Lintyco does not currently list a dedicated 3-side-seal machine in its standard catalog — but our engineers regularly configure HFFS and premade-pouch machinery for customers running this format. If you're scaling up 3-side-seal production, contact us with your product, target speed, and pouch dimensions, and we'll specify the right approach.
Specifications
| Common materials | PET/PE, PA/PE, paper/PE |
| Width range | 50–120 mm |
| Length range | 80–180 mm |
| Filling range | 10–200 g |
| Production method | HFFS / premade-pouch filler (custom tooling typically required) |
Common applications
- ▸Sample-size portions & single-serve sachets
- ▸Condiments, sauces & spreads
- ▸Desiccant & oxygen absorber packets
- ▸Pharmaceutical sample packs
- ▸Spice & seasoning pouches
- ▸Powdered drink & protein stick packs
- ▸Coffee & tea sample pouches
- ▸Contract-packed promotional samples
Pros & cons
Advantages
- ✓Lower tooling cost than 4-side-seal (3 seals instead of 4)
- ✓Compatible with premade-pouch fillers (no custom forming tube)
- ✓Flexible filling — manual, auger, or liquid fill before final seal
- ✓Good for short runs and contract packaging
- ✓Compact, flat format suits sample-size retail display
Limitations
- ✗Not tamper-evident until final top seal is applied
- ✗Slower cycle than inline VFFS (separate fill + seal steps)
- ✗Lower maximum barrier than 4-side-seal (one less hermetic edge)
- ✗Requires a custom-tooled HFFS or premade-pouch filler
Machines that make this bag
Talk to a Lintyco engineer about 3-side-seal bags
3-side-seal pouches aren't a standard catalog configuration — but we regularly build custom HFFS tooling for them. Tell us about your product and we'll recommend the right approach.
Contact sales about this bag →Get a quote for 3-side-seal bag machines
Tell us about your project — we'll reply within one business day with a configured quote.
Frequently asked questions
What is a 3-side-seal bag used for?
3-side-seal bags are commonly used for sample portions, single-serve condiments, desiccant packets, and short-run contract packaging where pre-made pouches are purchased separately and filled on simpler sealing equipment.
How is a 3-side-seal bag different from a 4-side-seal bag?
A 3-side-seal pouch leaves one edge (usually the top) open for filling, then closes it after the product is loaded. A 4-side-seal pouch is sealed on all four edges in a single manufacturing cycle — the product is loaded during forming, not after. 4-side-seal offers higher integrity; 3-side-seal offers more flexibility in filling method.
Can Lintyco machines make 3-side-seal pouches?
Lintyco doesn't list a dedicated 3-side-seal machine in its standard catalog, but our engineers regularly configure HFFS and premade-pouch machinery for this format. Contact sales with your spec for a custom configuration.
What materials are typical for 3-side-seal bags?
Common structures are PET/PE for general packaging, PA/PE for vacuum or modified-atmosphere applications, and paper/PE for sustainable retail formats. Barrier coatings and foil laminations are available for moisture-sensitive products.