The compound bag heat sealing problems, full

Composite bag heat sealing layer of material type, thickness and material quality's influence on the heat sealing strength is the most direct, so the professional manufacturer of flexible packaging packaging today is to summarize the problem of heat sealing compound packing. General composite bags commonly used heat sealing materials have the CEP, LPPE, CPP, OPP, EVA hot melt adhesive resin and other ionic co-extrusion or blending modified membrane. The thickness of the heat sealing material, generally 20 & ndash; 80μ Floating between m. Special cases also have 100 & ndash; 200μ M, the same kind of heat sealing material, the heat sealing strength increases with the thickness of the heat sealing. Cooking bags, for example, the heat sealing strength of general requirements of 40 & ndash; 50 Newton, therefore, the thickness of heat sealing should be in the 60 s & ndash; 80μ M above. Involved in the process of heat sealing bag making temperature, temperature control depends on the temperature display instrument. In the process of heat sealing compound bag processing and as precise as possible to the requirement of thermometer, error planning and set value is not greater than best & plusmn; 5℃。 Heat sealing temperature on heat sealing strength most directly, the influence of melting temperature of various materials, concave and convex, directly determine the minimum heat sealing temperature compound bag. In practical production process, the heat sealing pressure, bag making machine speed and the thickness of the composite substrate aspects of influence, the actual use of the heat sealing temperature tend to be higher than the melting temperature of the heat sealing materials. Heat sealing pressure is smaller, for heat sealing temperature is higher, the faster machine speed, the surface of composite membrane material is thicker, the requirements of the heat sealing temperature is higher. If the heat sealing temperature is lower than the heat sealing material softening point, no matter how to increase the pressure or heat sealing time, all can't make the heat sealing layer sealing. However, assume that the heat sealing temperature is too high, and easy to harm welding side heat sealing materials, melting extrusion happen & other; Root cutting & throughout; Phenomenon, greatly reduces the sealing heat sealing strength and impact resistance function of composite bags. In the process of actual bag heat sealing and heat sealing tool pressure often choose can rotate to adjust the spring. General tool adjustment process is composed of two springs, points on both ends of the left, right, assumed stress affect the heat sealing strength, testing method is: in a composite bags look carefully stitch is processing, assuming uniform pressure is not going to happen bubble phenomenon; Another way is, with 500 px, 75 px, 5000 px wide special lubrication bamboo piece of experiment, due to the pressure is insufficient, low intensity, tend to appear leakage phenomenon, so the uniform pressure and low temperature is to reduce strength, one of the basic stratification.