Evaluation of Voids on Shrink PVC Film

Abstract

Gravure is one of the most widely used processes for printing on shrink films, the
reason being its consistency for longer runs. However, such printing is accompanied
by new challenges. The presence of gels, black specks and other contaminations
in these films does not allow the surrounding area to print, thus 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 the minimization of print voids in Shrink PVC film. The gravure
process variables viz. viscosity, pressure, speed and hardness were identified
for the indirect laser cylinder. It was established that hardness had a significant impact
on minimizing the voids, while viscosity-hardness interaction played another
important role. The results showed the reduction in void area with lower viscosity,
higher pressure, lower speed and higher hardness.