1. The Ph value of the waterproof adhesive must be controlled within the prescribed limits. 

2. The product must be heavier than the normal product. 

3. Use as much heat energy as possible in the production of paperboard. 

4.Tissue Moisture should not be too high. 

5.More agitation is necessary and the waterproof adhesive in the tank must be used as soon as possible; 

6. If the effect is still not good, the only remedy is to add more resin.