The reason is that the water control roller is too hard, or the chrome delivery water roller device is poor, and it may be gear wear. The countermeasure is to check if the hardness of the water roller is replaced if necessary, or to re-correct the pressure between the chrome transfer roller and the plate roller, and check the gears of the control roller and the chrome delivery roller. Occasionally, the surface of the water roll of the wet system occupies the ink and must be cleaned and removed.