Carton printing ghosting analysis and exclusion

The printing quality of cartons is increasingly valued by cartons users and consumers. In the production process of cartons, it is inevitable that various conditions will affect the printing quality of cartons. The ghosting problem is particularly common. As long as the reasons for the correct analysis are taken and effective measures are taken, the problem of printing ghosting can be well resolved and effectively avoided.

Inappropriate viscosity adjustment due to ink viscosity

When the ink has a large consistency and a strong viscosity, a slight slippage occurs during the imprinting process of the printed sheet, which can easily cause a ghosting failure. Especially when the gripper teeth have insufficient bite force, longitudinal ghosting is more pronounced. In view of this situation, in actual operation, as long as a good ink transfer process is turned off, adding an appropriate auxiliary agent to reduce the viscosity of the ink, it can better eliminate the ghosting failure caused by improper ink viscosity adjustment.

Plates are not taut or "ghosting"

At the time of loading, due to the lack of scientific operation knowledge, the tightening screws of the printing plate were not evenly tightened in order, resulting in uneven elasticity of the surface of the roller and slight protrusions in the printing plate; the back pad of the printing plate was too soft or partially used. More pad or pad to make its critical empty; dirty cleaning of the printing roller surface left double-sided adhesive residue, are likely to cause local ghosting. The key to correcting the problem of local ghosting is to combine the well-installed operation technology with the pad layout technology. That is, when the printing plate is tightened, gradually tighten the screws in order, and do not tighten one of the screws first. Make the plate can not fully and evenly close to the surface of the roller. In addition, pad the back of the plate, the texture should be a bit harder, and try to avoid the local multi-pad or knock out, in order to achieve the effect of eliminating ghosting failure.

Ghosting caused by excessive press adjustment

When the pressure between the blanket cylinder and the impression cylinder is too large, the deformation displacement of the blanket will inevitably increase correspondingly, so that the ink cannot be restored to the original state immediately after the ink transfer during the imprinting process. In this way, a slight difference in position is generated when receiving the imprint from the plate cylinder, forming a ghost. In this regard, the operator in the actual operation, as long as the appropriate reduction of roller pressure, reduce the blanket expansion coefficient, this failure can be eliminated.

Ghosting due to abnormal drum work

When the drum-related components are not adjusted or worn, each time the pressure is built up, it will produce a certain difference in position, resulting in a different position of the imprinting. In this case, the ghost caused by the recalibration and adjustment of the clutch-pressing mechanism should be And repair the wear parts, make the work of the roller and clutch work accurately, coordinate, and unify, and this type of fault can be eliminated.

Insufficient pressure due to paper pressure

When the roller teeth are worn and deformed due to use, the force exerted on the printed sheets during the imprinting of the roller is insufficient, so that the printed sheets are slightly slipped from the teeth during the imprinting, and each slip amount is not the same. In the next printing, there was a ghosting in the chin area due to the fact that there was no accurate overlap between the blurred blots retained on the blanket and the retransferred ink. In this regard, during the printing process, technicians should inspect the teeth of the roller, and if the deformation is not uniform or insufficient, it should be re-adjusted. If the surface of the crepe paper is worn out, the new accessories should be replaced to ensure that the paper teeth do not slip and the ghosting of the mouth area is eliminated.

Looseness due to looseness of roller gear or bearing wear

When the printer was used for a long period of time, the maintenance and repair work was not carried out conscientiously, resulting in serious abrasion of the roller gear or bearing. In the process of imprinting, vibration would inevitably occur and the imprinting ghost would follow. In this regard, the technician should repair the worn parts and the fault can be eliminated.

Dirty lining caused by roller lining

When the difference between the lining diameters of the plate cylinder and the blanket cylinder is too large, due to the excessive inconsistency of the line speed at each imprint, speed difference and friction occur, the surface of the blanket is squeezed and deformed, and the inner liner material is easily moved. Until the wrinkles, blotting ghosting faults follow. In this regard, technical personnel should re-measure the center distance of the roller, control the thickness of the lining according to the equipment specification, keep the line speed of the roller consistent, and avoid the occurrence of printing ghosting.


Source: Corrugated Box