Cause Analysis of Puncture – Example of three-Side Seal Pouch
Puncture refers to a through-hole or crack in the packaging material, particularly during the production of three-side seal pouch, caused by external force or pressure. This defect significantly affects the packaging integrity, leading to issues such as air leakage during inflation, failure to achieve proper vacuum sealing, and leakage in the containment of liquid products.
In the production of three-side seal pouches, the puncture generally occurs under the following conditions.
1. Excessive heat sealing pressure, uneven heat sealing molds, or the presence of particulate matter on the film surface are common in the heat sealing process of three-side seal pouches.
These factors may result in excessive localized pressure, which can cause punctures in more fragile packaging materials. Especially with the wider use of thinner materials such as aluminum foil in three-side seal pouches, they are more prone to damage.
2. Rough surfaces, edges, or foreign particles in the heat sealing mold are also significant causes of punctures.
Poor heat sealing molds can damage packaging materials in three-side seal pouch production. Sharp edges from mold damage or foreign particles on the mold or base plate can leave marks on the heat seal area, known as 'air holes,' leading to air leakage. Hard particles, such as unplasticized crystals on PE films, can also cause punctures.
3. Improper material thickness is also a key factor in punctures of three-side seal pouches.
In three-side seal pouch production, some machines require specific material thickness. If too thick, areas like the side seals may be punctured due to excessive pressure. If too thin, the center seal, especially in pillow-style pouches, is prone to damage, such as in OPP, ONY, PET/AL/PE lamination.
