Common packaging issues include leakage, weak seals, delamination, punctures, inconsistent printing, incorrect dimensions, zipper failure, and poor filling-line performance. Most problems result from a mismatch between the product, material structure, pouch design, production settings, or distribution conditions rather than from one isolated factor.

Recognize the Failure Pattern

The location and timing of a defect provide useful clues. Damage appearing immediately after filling may have a different cause from failure found after pallet transport.

Why Do Pouches Leak?

Leakage can occur through side seams, bottom folds, zipper ends, spout joints, or small holes in the film. Powder, oil, crumbs, and liquid trapped in a seal can create channels that are difficult to detect visually.

A reliable packaging supplier should test filled bags rather than relying only on empty-pouch inspection. Seal-strength testing, pressure checks, drop trials, and leak detection help identify where the package loses integrity.

Increasing film thickness alone may not solve the problem. Seal geometry, inner-layer compatibility, and filling cleanliness can be more important.

What Causes Delamination?

Flexible packaging usually contains multiple films bonded with adhesive. Insufficient adhesive application, incorrect mixing, incompatible inks, high residual solvent, or inadequate curing can weaken the laminate.

Chemical interaction with oily, acidic, or strongly flavored contents may also affect long-term bond performance. The actual product and expected storage period should therefore be considered during material selection.

Visible bubbles, tunneling, curling, or separation at cut edges may indicate a lamination problem. Production should not proceed to full conversion until the laminate has completed its specified curing period.

Why Do Bags Fail on Filling Lines?

Automatic equipment requires consistent pouch width, film stiffness, opening behavior, zipper position, and surface friction. Bags may slip, double-feed, refuse to open, or move out of alignment when these factors vary.

The filling opening must also suit the product and dosing system. Insufficient headspace increases contamination around the top seal, while an overly soft film may be difficult for suction cups or grippers to handle.

Machine trials should use production-representative material because a paper mock-up cannot reproduce actual feeding and sealing behavior.

Printing and Dimension Problems

Color variation may result from different substrates, ink density, lighting, surface finish, or lamination. Registration problems can place text or graphics too close to seals and folds. Incorrect gusset depth can reduce volume or cause poor standing stability.

Approved dielines, physical color standards, dimensional tolerances, and signed samples provide clear production references. Barcodes and small regulatory text should be checked on the finished pouch, not only in the artwork file.

Prevent Repeat Defects

An OEM packaging factory should record the laminate, thickness, dimensions, zipper type, artwork version, sealing parameters, inspection criteria, and packing method for each approved order. Retained samples make future batch comparisons easier.

Corrective action should address the root cause rather than only sorting defective bags. Product data, production records, and failed samples together usually reveal whether the solution belongs in material design, equipment adjustment, process control, or logistics handling.