The appearance of ghosting makes the thin lines thicker, and the original dots become one and a half or two, which makes the graphics and text of the whole printed matter blurred and the clarity is obviously reduced.
Ghosting often occurs at the beginning of printing; When the drums are pressed together and the drums are pressed apart; When the printing plate cylinder contacts and separates from the printing surface of the rubber cylinder; When the rubber drum contacts and separates from the printing surface of impression cylinder; When the printing plate cylinder and the paper transfer cylinder hand over the paper; When the supporting cots start to contact or leave the printing plate and the printing speed changes.
According to the direction of ghosting, the types of ghosting can be divided into vertical ghosting, horizontal ghosting and A and B ghosting.
Vertical ghost, also known as up and down ghost. The virtual shadow of the point is at the upper and lower ends of the origin, and its position is fixed in the direction perpendicular to the axial direction of the drum.
Horizontal ghost, also known as ghost. The virtual shadow of the dot is on the left and right sides of the original dot, parallel to the axis of the drum or at a certain angle. The virtual shadow is light and heavy, and its position is fixed.