This is a flat bottom coffee bag made from Kraft/PLA film, 130 microns thick, with side panels, no zipper and a heat-sealed top. It is gravure printed with your artwork, made to your dimensions, and the minimum order is 1,000 pieces. It is made for specialty coffee, roasted beans and suitable blends, and it sits in our coffee packaging range from BIOPOUCHES.

Flat Bottom Construction

A flat bottom bag has a rectangular base, side panels and defined corners. Filled, it takes a box-like shape. Before filling it is folded or fairly flat, and the shape develops as the coffee goes in. It is not a stand-up pouch or a pillow bag.

The base is stable on a shelf, the front and side panels carry branding, and consistent dimensions help with filling, packing and arranging cartons.

Two things are hard to get right in production. The bottom folds have to be accurate, or the filled bag may lean. The seals also have to be consistent where several film layers meet at the corners, or the corner seals come out uneven.

Kraft/PLA Material and Coffee Protection

Each part of the structure has a job. Kraft paper gives the paper look and a printable surface. PLA-based film can be part of a compostable structure, depending on the laminate and sealing system. The heat-seal layer has to match the material and the sealing conditions.

Barrier is the other concern. Roasted coffee loses aroma and quality when air and humidity get in, so moisture and oxygen protection matter. Kraft paper and PLA do not guarantee enough oxygen protection by themselves, so the laminate is assessed against your coffee type, filling conditions, storage period and barrier needs. Freshly roasted coffee also releases carbon dioxide, so a one-way degassing valve is optional and confirmed during product development. It is not standard.

How We Manufacture Flat Bottom Coffee Bags

1. Specification review. We check fill weight, dimensions, artwork, film structure and sealing requirements.

2. Printing. Gravure, with artwork positioned around the front, back, side panels and folds.

3. Lamination and curing. Where the structure needs it, bonding and process control come before conversion.

4. Pouch forming. Cutting, folding and alignment are controlled so the base opens correctly and corners stay consistent.

5. Heat sealing. Conditions have to suit the laminate, especially at corner intersections where layers overlap.

6. Finished pouch inspection. Dimensions, print registration, bottom construction and seal appearance before packing.

Production SOPs and Quality Control

Production follows SOPs, so operators repeat each step the same way from run to run. Equipment is cleaned daily and production records are kept. The main checks:

• Material and printing: film appearance, material suitability, color consistency and print registration.

• Pouch conversion: cutting accuracy, bottom folding, panel alignment and finished dimensions.

• Heat sealing: temperature, pressure and dwell time suited to the material.

• Finished bags: seal appearance, weak or incomplete joints, wrinkles and visible defects.

Packaging Testing and Verification

Four lab tests matter most for a bag like this. Heat-seal strength testing shows whether the sealed joints are strong enough for handling and filling. Seal-integrity or leak testing helps find leakage paths that would compromise protection. Tensile testing measures film strength under pulling. Coefficient-of-friction testing shows how the film moves during printing, conversion and filling.

Testing matters more with compostable or alternative films, because materials behave differently when sealed and converted. Which tests apply depends on the order. Our factory photographs show the equipment, and our article on flexible packaging printing and quality control covers how printed film is inspected.

Packing and Shipping

Finished empty bags are counted, stacked or bundled neatly and packed in protective cartons, and carton quantities are checked. Order volume, packed carton dimensions, weight, destination and delivery requirements decide the shipping plan. Air or sea freight is chosen to suit the order.

Technical Specifications