Heat sealing time will also affect the heat seal strength of the product. Under normal circumstances, under the same heat sealing temperature and pressure, a longer heat sealing time can make the heat sealing part more firmly and perfectly sealed, and can better achieve the expected heat sealing strength. However, the process conditions of modern high-speed pharmaceutical packaging machines cannot provide a long time for heat sealing. If the heat sealing time is too short, the heat sealing between the adhesive layer and the PVC film will be insufficient. For this reason, the national standard stipulates that the scientific heat sealing time is 1 second.
