Aluminizing delamination problem solving method

Aluminizing on vacuum aluminum-plated PET film, after coating with two-component polyurethane adhesive and other film dry complex, why does aluminum plating from the PET film on the adhesion and delamination?
The reason for this is that the adhesive strength of polyurethane adhesives is very large and often exceeds the adhesion of aluminum plating on the PET surface.
On the other hand, in China's vacuum aluminized film, there is no top coat protective layer on the aluminized layer, so it is recommended to engage in vacuum aluminum plating manufacturers, in addition to the primer on the aluminized substrate film, after the use of aluminum plating The two-component polyurethane rubber is coated with a top coat to protect the aluminum plating from being rubbed off by the friction and adhesive bond.
Because of the small mass of polyurethane glue, the small cohesive force, and the great activity of the glue, it is easy to infiltrate into the aluminized layer (only 400-600 thickness) to form a firm one with the aluminum plating, while the ethyl acetate in the PU glue is in PET. The adhesion between the surface and the aluminum plating results in the presence of PET on the aluminum-plated surface, which in turn weakens the adhesion between the PET surface and the aluminum plating, resulting in separation of the PET from the aluminum plating.
Solution: Apply the two-component PU glue on the surface of another substrate that is compounded with it to reduce the amount of ethyl acetate penetrating into the inner layer of the aluminum plating and prevent it from falling off. During operation, attention should be paid to adjusting the tension to a lesser extent so as to prevent the vacuum aluminum plating substrate film from being elastically deformed under a large tension, thereby affecting the adhesion of the aluminum plating. When dry recovery, the temperature is appropriately increased and ethyl acetate is used.
When dispensing gum, add some ethyl acetate appropriately. Appropriately increase the heating temperature, accelerate the cross-link curing reaction rate of PU glue, and reduce or prevent the penetration of the glue on the vacuum aluminum plating layer.