The higher the sealing temperature, the better. 

In the previous article, Leadtra Packaging has introduced the problems that may occur when the sealing temperature is too high or too low. Today, we will learn what is the best sealing temperature. 

The ideal sealing process is to find the "sweet spot" (optimal sealing window) that perfectly combines temperature, pressure, and time. This depends on: 

The structure of sealing film: especially the material type of heat sealing layer (such as LDPE, CPP, etc.) and its melting point. 

Bottle mouth material: Is the material of the bottle mouth HDPE, PP, PET or glass? The thermal conductivity and surface energy of different materials vary. 

Equipment parameters: sealing mouth size, pressure uniformity, heating method, etc. 

Practical suggestions: 

Following supplier guidance: Sealing film manufacturers typically provide a recommended temperature range based on their product characteristics. This is the best starting point. 

Process validation: On the actual production line, temperature parameters are validated and fine tuned through "heat sealing strength testing" and "sealing integrity testing" (such as dye penetration testing). 

Consider environmental factors: The ambient temperature of the production workshop and the temperature of the bottle body (such as cold or hot filling) will affect the actual required heat sealing temperature. 

Special case: Do high-temperature resistant films require higher temperatures? 

This is a common question. In fact, the heat-resistant aluminum foil film used for high-temperature cooking products does require a higher initial sealing temperature for its heat sealing layer (such as special CPP) to achieve a firm seal. But this is also a higher 'optimal range', rather than 'the higher the better'. The core of its design is to ensure that the seal does not detach during the subsequent high-temperature sterilization process (such as 121 ℃), rather than using extreme high temperatures during sealing. 

The sealing temperature of aluminum foil sealing film pursues precision rather than extremes. Blindly increasing the temperature not only fails to improve the sealing effect, but may also cause a series of quality problems, increase production costs and risks. Successful sealing comes from a deep understanding of material properties and precise control of sealing process parameters. 

If you have any questions, please feel free to contact our technical team through the contact information on both sides of the website. We will provide you with professional product selection and process parameter support.