Pulp Packaging Detachment Phenomenon Causes and Solutions!

Pulp packaging detachment phenomenon is pulp packaging composite bags often appear a quality failure, especially in the production, transportation, storage process, in the edge, the corner of the heat sealing place is prone to local or overall delamination phenomenon, and most of the printing surface of the larger products, especially in the surface of the ink layer is thicker, the adhesive is difficult to wetting, diffusion, infiltration of the case, it is more likely to paper-plastic packaging detachment phenomenon. The emergence of pulp packaging detachment phenomenon is often associated with the smoothness of paper, uniformity, moisture content, film performance, printing ink layer thickness, paper-plastic packaging composite temperature, pressure, the production environment (sanitation and temperature, relative humidity and other factors). According to the specific circumstances of the production, take targeted measures to deal with.

1 Cause Analysis

　　(1) Delamination in the middle of the paper, the film surface 100% sticky paper

　　This problem reflects the poor adhesion between the paper fibers, or the adhesion between the fibers is less than the film and paper surface fiber adhesion.

　　(2) In the pulp packaging interface delamination, and in the film surface partially adhering to the paper

　　This problem reflects excessive deviation in the thickness of the paper, insufficient gluing, or small composite pressure (or large changes in the input air pressure), or low composite temperature.

　　(3) Delamination at the interface of ink and adhesive

　　This problem reflects poor heat resistance of the ink, or the temperature of the paper bag is too high, or the melting point of the heat sealing layer film is too high, or the temperature deviation of the heat sealing knife itself is too large.

　　(4) Peeling in the middle of the ink layer or delamination between layers of different colors of ink.

　　This problem reflects the whitening of ink or poor ink quality, or the use of different manufacturers' inks for the same print, or poor ink drying.

　2、Solution

　　(1) Increase the amount of glue

　　If the adhesive is absorbed by the paper and printing ink resulting in insufficient coating volume, which causes the pulp packaging detachment, the amount of glue should be increased appropriately to ensure that the need for composite.

　　(2) In the printing ink is dry before composite

　　When the ink layer is not dry or not dry, the residual solvent in the ink layer may consume part of the adhesive, resulting in insufficient amount of adhesive, so that the adhesion between the pulp packaging decreases, resulting in the phenomenon of detachment of pulp packaging. In this case, after the ink is dry and then composite, can solve the problem of pulp packaging detachment.

　　(3) Improve the composite temperature and pressure

　　Composite, if the temperature, pressure is low, may also cause pulp packaging detachment phenomenon, should be appropriate to increase the composite temperature, pressure.

　　(4) Ensure that the surface tension of the film

　　Film surface corona treatment strength is not enough or film surface corona treatment after storage time is too long resulting in insufficient surface tension of the film, is also one of the important reasons for the detachment of pulp packaging. When the phenomenon of pulp packaging detachment, the surface tension of the film should first be tested, such as the surface tension is found to be insufficient, should be replaced with a film that meets the requirements.

　　(5) In the air humidity is not enough to use artificial humidification processing

　　As the pulp packaging composite using a one-component solvent-free adhesive, if the air moisture is insufficient, will also cause the phenomenon of pulp packaging detachment, which should be based on the humidity requirements of one-component solvent-free adhesive processing technology, artificial humidification treatment.