热封温度 Heat sealing temperature 复合膜的热封温度的选择与复合基材的性能、厚度、制袋机的型号、速度、热风压力等有密切关系，直接影响热封强度的高低。 The thermal sealing temperature of the composite film is closely related to the properties, thickness, the model, speed and hot wind pressure of the compound substrate and directly affects the heat seal strength. 复合薄膜的起封温度是由热封材料的黏流温度或熔融温度决定，热封的温高温度不能超过热封材料的分解温度。黏流温度与分解温度之间的温度即为热封材料的热封温度范围，它是影响和控制热封质量的关键性因素。热封温度范围越宽，热封性能越好，质量控制越容易、越稳定。 The sealing temperature of the composite film is determined by the viscous flow temperature or molten temperature of the heat-sealed material. The temperature of the hot seal cannot exceed the decomposition temperature of the heat sealing material. The temperature between the viscous flow temperature and the decomposition temperature is the heat sealing temperature range of the heat sealing material, which is the key factor affecting and controlling the quality of the heat seal. The wider the temperature range, the better the heat sealing performance, the easier and more stable the quality control. 同时复合薄膜热封温度不能高于印刷基材的热定型温度。否则会引起热封部位的收缩、起皱，降低了热封强度和袋子的抗冲击性能。印刷基材的耐温性好，如BOPET，BOPA等，提高热封温度能提高生产速率；印刷基材的耐温性差，如BOPP则尽量采用较低的热封温度，而通过增加压力、降低生产速度或选择低温热封性材料来保证热封强度。 At the same time, the heat sealing temperature of the composite film cannot be higher than the heat setting temperature of the printed substrate. Otherwise, it will cause the shrinkage and wrinkling of the hot seal, reducing the thermal seal strength and the impact resistance of the bag. The high temperature resistance of the printed substrate, such as BOPET, BOPA, etc., can improve the production rate of heat seal temperature. The resistance of the printed substrate is poor, such as BOPP, which tries to use the lower heat seal temperature, while ensuring the heat seal strength by increasing the pressure, lowering the production speed or choosing the low temperature heat sealing material.