Four reasons for corrugated cardboard softening and improvement methods

[China Packaging News] The hardness of the cardboard is still relatively good. After a day of putting it in the warehouse, the cardboard starts to soften. The softened cardboard seriously affects the physical indicators of printing and cartons, so why does this happen?

Cause Analysis

1. The amount of caustic soda in the glue is too large;

2. Overlapping stacking of offline cardboard is too high;

3. The temperature of the hot plate of the dryer is lower than 160 ℃ and the speed is too fast. The low temperature environment causes the illusion of drying, and the cardboard will quickly return to soft after stacking;

4. The relative humidity of cardboard storage environment exceeds 65% .

Improve methods

1. Properly reduce the amount of alkali used for glue;

2. Well-shaped stacking is adopted, and the stacking height should not exceed 1.5m . If necessary, use a blower to force ventilation to disperse the moisture in the cardboard;

3. Flexible control of the dryer speed according to the environment, temperature and paper quality, and check the quality of the cardboard at any time;

4. Strengthen the ventilation of the cardboard storage environment, the ground can absorb moisture with quicklime powder.