Pepper ball is a kind of hollow plastic ball, which has to bear certain pressure and impact force in the working environment, so there can be no air bubbles in the middle. The improvement method of air bubbles will have water in the plastic raw materials. If the water in the plastic is not fully dried before injection molding, this water will run into the blank of the pepper ball shell during injection molding. If the opaque pepper ball is basically invisible in appearance, it will also affect the performance and strength. Transparent pepper balls, such as PP pepper balls and PMM pepper balls, will visually see the bubbles inside, and the appearance is very ugly. The simple solution is to fully dry the plastic raw materials before production, so that the water in the plastic raw materials can be completely drained into the blank of the pepper ball and the occurrence of plastic bubble balls can be reduced.