If the roller surface dust imprint or Division of the pictures and texts are often presented with granula of blotchs, blotchs gap Department and foreign bodies report of sticky situation.

• 如果压印滚筒暗不天附着尘埃或异物在图不白处必然表示为颗粒性的雀斑，雀斑的空不天处与异物附粘境况相契合。