It can be widely used to clean printed boards, glass products, steel plates, aluminum plates and other panels. The sponge roller has many micropores, and the micropores are connected to each other, and the water absorption is very good. For oily substances, since the oil is an organic compound, when it penetrates into the sponge roller hole, it forms a closed state. It cannot absorb the grease better. The oil absorption is not good. The ink is dyed in the water, and the printing machine depends on water. The penetrating and flowing performance of the ink drives the dyes of the ink, and the poor penetrating performance of the dyes is left on the paper. The moisture is transparent and colorless, leaving only the dye marks. The paper just printed is moist.