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YLTpacking packaging: some common problems with plastic film gasketing

1. What effect does the heat sealing temperature have on the heat sealing strength? The heat-sealing temperature has a very important influence on the heat-sealing strength, and the film thickness of the heat-sealing layer involved in the heat-sealing plays a decisive role in the heat-sealing effect. ① When the temperature is relatively low, the surface of the heat-sealing layer is melted, and the thickness of the film participating in the heat-sealing is relatively thin, resulting in a lower contact temperature. ② When the temperature is too high, the heat-sealing layer film may be melted or the heat-sealing layer may be in danger of peeling off the base layer, causing the base layer of the upper and lower films to participate in the heat-sealing, which will inevitably lead to a decrease in the heat-sealing strength. Therefore, when we heat the film, we must choose a suitable heat sealing temperature, neither too high nor too low. 2. What is the effect of heat sealing time on heat sealing? The heat sealing time of an automatic packaging machine or an old-fashioned bag making machine is determined by the speed of the machine. Under the condition that the heat-sealing temperature and heat-sealing pressure remain unchanged, the longer the heat-sealing time, the stronger the bonding between the heat-sealing layers. However, if the heat sealing time is too long, the heat sealing part of the composite film will appear wrinkled and uneven, which will seriously affect the appearance quality of the product. 3. What effect does heat sealing pressure have on heat sealing? In order to ensure the heat sealing strength of plastic composite flexible packaging, a certain heat sealing pressure is essential. Therefore, the heat sealing pressure is required to be moderate and uniform during the heat sealing process. If the heat-sealing pressure is not enough or uneven, the heat-sealing part will generate air bubbles and cause virtual welding, resulting in poor heat-sealing. If the heat-sealing pressure is too large, the sealing part will be deformed. When the heat-sealing temperature is high, It will also squeeze out part of the composite material, causing the edge of the heat seal to become brittle and easy to crack, and at the same time to reduce the strength of the heat seal. 4. What are the causes of uneven heat sealing pressure? ①The heat sealing knife is deformed. Heat sealing knives are generally made of aluminum or copper with good heat transfer performance. Both of these materials are relatively soft, so when installing the heat sealing knife, if the method of tightening the fixing screws is incorrect, it will cause the heat sealing knife to not bear the force. Evenly, after frequent knife changes, the heat sealing knife is deformed. ②The machining accuracy of the heat sealing knife is low. The low machining accuracy of the heat-sealing knife will cause the surface of the heat-sealing knife to be uneven, which will cause uneven heat-sealing pressure during the heat-sealing process, thereby affecting the heat-sealing strength of the composite packaging bag. ③The surface of the heat sealing knife is dirty or damaged. If the surface of the heat sealing knife is stuck with stolen goods or has bumps and scratches on the surface, it will also cause uneven heat sealing pressure. In addition, the molten resin sticks to the surface of the heat sealing knife and is not cleaned in time, which will also affect the heat sealing strength. ④The hardness and strength of the silicone skin. The quality of the silicone skin is the most important condition to ensure uniform heat sealing pressure. Plastic film heat sealing, plastic film, plastic packaging bag, plastic bag, plastic packaging bag manufacturers:

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