1. Main reasons
There are many factors that affect the detachment of paper and plastic, such as the smoothness, uniformity, moisture content of the paper, various properties of the plastic film, thickness of the printed ink layer, amount of auxiliary materials, temperature and pressure during paper and plastic composite, hygiene conditions of the production environment, and temperature and relative humidity, all of which can have a certain impact on the final result of paper and plastic composite.

2. Handling method
(1) The ink layer of the ink is too thick, causing the penetration and diffusion of the adhesive, resulting in the detachment of the paper and plastic. The treatment method is to increase the coating amount of adhesive and increase the pressure.
(2) When the ink layer is not dry or fully dried, the residual solvent in the ink layer weakens the adhesive force and causes the paper plastic to detach. The processing method is to wait for the product ink to dry completely before compounding.
(3) The residual powder on the surface of printed materials can also hinder the adhesion between paper and plastic film, leading to the detachment of paper and plastic. The processing method is to use mechanical and manual methods to erase the powder on the surface of the printed material and then composite it.
(4) The operation process is not standardized, the pressure is too low, and the machine speed is too fast, resulting in the detachment of paper and plastic. The processing method is to strictly follow the process specifications, increase the pressure of the film coating appropriately, and reduce the machine speed.
(5) Adhesive is absorbed by paper and printing ink, and insufficient coating can cause paper plastic detachment. Re formulate the adhesive and determine the amount of glue to be applied according to the manufacturer's requirements.
(6) Insufficient or expired corona treatment on the surface of plastic film causes paper plastic detachment due to the failure of the treated surface. The plastic substrate should be corona charged or the plastic film should be renewed according to the corona standard for film coating.
(7) When using a single component adhesive, if the paper plastic detachment is caused by insufficient air humidity, manual humidification should be carried out according to the humidity requirements of the single component adhesive processing technology.
(8) Ensure that the adhesive is within its shelf life and stored and used according to the manufacturer's requirements, such as the two-component automatic glue mixing machine being in good condition, to ensure accurate, uniform, and sufficient proportioning.