There are three factors that affect the heat sealing strength of shrink film


With the rapid development of food, cosmetics, medicine and other industries, the demand for plastic composite packaging products is increasing, and the quality of plastic composite packaging products is also increasingly high. Packaging users not only pay attention to the appearance and logistics performance of packaging products, but also pay attention to the heat sealing strength of packaging products. Because the heat sealing strength of packaging products directly affects the packaging speed, transportation and sales.

In the actual production, the heat sealing strength is regarded as the most important quality index to control the bag-making products and the coil products used in the automatic packaging production line. The following is a simple analysis of the factors that affect the heat sealing strength of the heat-shrinkable film based on the actual production experience:

1. Heat sealing temperature: 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 machine or old bag making machine is determined by the machine speed. Under the condition that the temperature and pressure of heat sealing remain unchanged, the longer the time of heat sealing, the stronger the bonding between the heat sealing layers will be. But if the heat sealing time is too long, the heat sealing part of the composite film will appear fold, uneven phenomenon, seriously affect the appearance of the product quality.

3, heat sealing pressure: in order to ensure the heat sealing strength of plastic composite soft packaging, a certain heat sealing pressure is essential. Therefore, the heat sealing pressure should be moderate and even in the process of heat sealing. If the heat sealing pressure is not enough or uneven, it will make the heat sealing part produce bubbles and lead to poor heat sealing.