Three major factors affecting the heat sealing strength of pof shrink film

With the rapid development of industries such as food, cosmetics, and pharmaceuticals, the demand for plastic composite packaging products is increasing, and the quality requirements for plastic composite packaging products are also becoming higher. Packaging users not only focus on the aesthetics and logistics performance of packaged products, but also pay attention to the heat sealing strength of packaged products. Because the heat sealing strength of POF shrink film products directly affects packaging speed, transportation, and sales. In actual production, manufacturers consider heat sealing strength as an important quality indicator for both bag making products and roll products used in automatic packaging production lines. Based on practical production experience, a brief analysis will be conducted on the factors that affect the heat sealing strength of heat shrink films:

1. Heat sealing temperature: The heat sealing temperature directly affects the heat sealing strength of plastic composite packaging products.

2. Heat sealing time: The heat sealing time of automatic packaging machines or old-fashioned bag making machines is determined by the machine speed. Under constant heat sealing temperature and pressure, the longer the heat sealing time, the stronger the bond between the heat sealing layers. But if the heat sealing time is too long, wrinkles and unevenness will appear in the heat sealing area of the composite film, seriously affecting the appearance quality of the product.

3. Heat sealing pressure: In order to ensure the heat sealing strength of plastic composite flexible packaging, a certain heat sealing pressure is essential. Therefore, moderate and uniform heat sealing pressure is required during the heat sealing process. If the heat sealing pressure is insufficient or uneven, it will cause bubbles to form in the heat sealing area and result in virtual welding, leading to poor heat sealing.