The reason of migration of aluminum coating on aluminum coating
Release time: 2020 / 06 / 22 10:31:52 reading volume: 1509 times
Aluminum plating film not only has the characteristics of plastic film, but also replaces aluminum foil to some extent, which plays a role in improving the product grade, and has relatively low cost Leisure food packaging It is widely used. However, in the production process, the transfer of aluminum coating often occurs, which leads to the decrease of the peeling strength between the layers of the composite film and the performance of the product, and even affects the quality of the packaging contents seriously. What are the reasons for the transfer of aluminum coating? What should be paid attention to in the operation of composite process?
one The bonding firmness between the aluminum coating and the base film is poor.
two The selected adhesive is not suitable.
three The curing time of composite film is too long.
four The amount of glue is too large, the adhesive drying is not enough, and the residual solvent gradually permeates into the aluminum coating, resulting in the migration of the aluminum coating.
five If the tension is not controlled properly, the base film of the aluminum coating will deform elastically under a large tension, which will affect the adhesion of the aluminum coating, which is also one of the factors that promote the migration of the aluminum coating.
Industry experts suggest: the main reason for aluminum transfer or film deformation, secondary reason is adhesive. At the same time, the aluminized structure is most afraid of water, even if a drop of water penetrates into the composite layer of aluminum coating film, serious delamination will occur.
two Corresponding solutions
one Replace the aluminum coating with good quality.
two Replace the appropriate adhesive, the best is the special adhesive for aluminum coating.
three The curing temperature should be increased and the curing time should be shortened, the curing reaction speed of adhesive should be accelerated, and the adhesive force between the base film and the aluminum coating should be weakened.
four Control the amount of glue coating, or adjust the drying temperature, ventilation rate and composite line speed of dry laminating process to ensure the adhesive is fully dried, and control the residual solvent amount within the minimum limit, so as to reduce its impact on the aluminum coating.
five Adjust the tension setting, and pay attention to the appropriate small tension to prevent large elastic deformation of aluminum coating.
There are many kinds of aluminized films on the market OPP 、 CPP 、 PET Etc. They are divided into transfer aluminum coating, laser anti-counterfeiting aluminum coating, ordinary aluminum coating, etc. Common aluminized flexible packaging structures are as follows: OPP/VMCPP ， OPP/VMPET ， PET/VMPET ， VMPET/PE （ CPP ）Etc.