Leveling is one of the basic requirements of people for plastic soft packaging. But in the actual production process, after the bag is sealed by heat, the sealing area is prone to fold, which affects the beauty and utilization rate. that
How to avoid this problem?
1、 Material issues
If the material is not temperature resistant, the sealing position will easily wrinkle after high temperature sealing and ironing. For example, the material of bopp/pe is soft and lacks hardness, so when heat sealing
If the temperature is too high, folds are prone to occur. It is suggested that the film with good flatness and certain hardness, such as PET film, should be added in the middle layer of the packing bag composite, so as to solve the problem of the material
Fold problem caused by material.
2、 Heat seal time and temperature
The temperature of the hot seal is too high, the packaging bag can not bear the temperature, and it is easy to be ironed and wrinkled. But the temperature of heat seal is not enough, which leads to low strength of heat seal, and it can not guarantee the effect of heat sealing. And at the temperature
If the degree is the same, the fold will occur if the heat sealing time is too long.
Therefore, the temperature of heat seal should be set reasonably according to the different materials. To solve this problem, the smart heat sealing machine introduced from Holland by horizontal packaging is carried out through the control panel
Set the temperature and time of heat seal accurately, and display the data on the front LCD. During each heat seal process, three sealing parameters, i.e. temperature, speed, excitation, and any, can be monitored simultaneously
If any parameter deviates, the equipment will alarm and suspend operation to ensure the quality of heat seal.
3、 Adhesive residue
If the adhesive is not dry enough, the adhesive will decrease the adhesion and the two kinds of substrate will be displaced. In order to solve this problem, it is suggested that the adhesive should be adjusted properly
The technical parameters can make the adhesive dry sufficiently and reduce the solvent residue.
The cooling process is to set the material which has just been fused and sealed with lower temperature under certain pressure, eliminate stress concentration, reduce weld shrinkage and improve the flatness of bag.
Therefore, if the cooling water temperature is too high, the pressure of the cooling rod is not enough, the cooling cycle times are not enough, etc., it may lead to poor cooling, and then the bag will wrinkle.