Uflex has become the first Indian company to manufacture a glitter printing rotogravure cylinder on its direct laser engraving line. Pigments of glitter ink are substantially bigger in size compared to conventional gravure inks, therefore rotogravure printing on substrates using such inks has always been a challenge for converters.
“It is extremely difficult for a cylinder with electro-mechanically engraved conventional gravure cells to pick up pigments of the glitter ink and transfer them on to the substrate, therefore in the case of this specialized cylinder, we developed bigger sized customized pits (cells) that trap the high solid content of the glitter ink,” explains P.K. Agarwal, joint president of cylinders at Uflex. “The customization of cell geometry of the rotogravure cylinder on our direct laser engraving line is the real innovation here. Pigments of the glitter ink have a tendency to get stuck inside the pits/ cells of the cylinder (cell filling). When the printing surface is sandwiched between the impression roller and the gravure cylinder, the high solid contents of the glitter ink get transferred from recessed cells to the substrate with the help of capillary action and the tangential force of the roller.
“Glitter ink, unlike other conventional gravure inks, do not possess self-curing properties. Therefore to enable quick and effective curing of the glitter ink, we developed an LED curing system and installed it on the proofing/printing machines at Uflex. The high solid content of the glitter ink on the printing surface/substrate imparts superior tactile effect along with the shimmer, tremendously enhancing the shelf impact of the pack thereby catching the attention of the customer at the already inundated point of sale. It took us about one month to develop the glitter printing rotogravure cylinder. Our Chemicals Business simultaneously developed the glitter ink. There is great demand for this type of printing from the converters of flexible packaging for high impulse buying consumer goods, particularly in the food and confectionery segment, for which we are fully braced.”
The specialty glitter ink has been manufactured for flexible substrates like paper and heat sensitive films and can be cured using LED lamps applied in-line with gravure printing process using a solvent or water-based ink system.