Evaluation of Voids on Shrink PVC Film by Varying Gravure Process Variables

Gravure is one of the widely used processes for printing on shrink films, the reason being its consistency for longer runs. However, printing these shrink films comes with new challenges. The presence of gels, black specks and other contaminations in these films do not allow the surrounding area to print resulting in print void. The occurrence of this defect in a considerable amount or size on the area of interest leads to the rejection of printed stock that involves wastage of inks, solvents and time. The research involves the investigation of the effect of gravure process variables on minimization of print voids in Shrink PVC film. The gravure process variables viz. viscosity, pressure, speed and hardness were identified for laser engraved cylinder. It was found that Hardness had a significant impact on minimizing the voids while Viscosity-Hardness interaction was important. The results showed reduction in void area with lower viscosity, higher pressure, lower speed and higher hardness.