Three-Side-Seal Bags: Prove the Batch Code on a Filled Line
Check batch-code readability on filled three-side-seal bags during the actual production sequence.
A batch code can be legible on a flat film proof and hard to read on a filled pack. Kaida Group lists a three-side-sealing bag among its formats. The buyer's task is to choose a coding zone that survives filling, closing, handling and retail display.
Locate the code on the finished pouch
Start with the actual bag dimensions and target fill. Mark the seals, folds and the area that bulges around the contents. Place a temporary code at several possible positions on filled samples, then view the pack in its carton and intended display position.
Ask the production team which printer will apply the code, how the pouch passes the printer and how the line checks a bad or missing mark. The suitable area depends on the equipment and the surface that remains accessible at that point. Keep the coder type and line direction on the artwork drawing.
Test a normal production run
Make a short run using the real contents and code format. Take samples from start-up, steady running and after a film or bag changeover. Examine contrast, character completeness and whether a seam, wrinkle or product pressure distorts any part of the code.
Let the quality team define how it will judge readability and what information must appear for each sales market. Use the same lighting and reading method at every sample check. If the line uses a scanner or camera, include that equipment in the trial and record rejected units.
Keep code and artwork versions connected
Reserve a coding zone on the approved print file and maintain clearance from essential graphics. Update the line setup sheet when pouch dimensions, print design or contents change. A new fill volume can shift the bulge enough to affect a location that worked earlier.
Send Kaida a filled sample, the code specification, printer position and trial results. The final bag drawing can then identify a proven coding location and a repeatable inspection step, rather than leaving code placement to the last day of production.