What are the common causes of weak package seals?
• Heat-seal temperature too low or fluctuating beyond ±5°C, below film melting point; verify with pyrometer.
• Insufficient heat-seal pressure or uneven sealing jaw, causing non-uniform contact; check pressure and level jaws.
• Heat-seal dwell time too short for full melting; adjust to the process window.
• Product contamination in seal area, unstable film tension or poor cooling, leading to false seals or low peel strength.
• Film and sealant layer mismatch or contamination; run peel strength test and switch to compatible film.
• Insufficient heat-seal pressure or uneven sealing jaw, causing non-uniform contact; check pressure and level jaws.
• Heat-seal dwell time too short for full melting; adjust to the process window.
• Product contamination in seal area, unstable film tension or poor cooling, leading to false seals or low peel strength.
• Film and sealant layer mismatch or contamination; run peel strength test and switch to compatible film.