With the rise in government regulations worldwide and public demand for greener technologies, the upcoming technology of water-based gravure printing is gaining momentum globally. The process involves specially engraved cylinders and the use of water-based ink and rotogravure presses that have efficient curing systems. Widely accepted in other Asian countries, including China, it is nevertheless a new ecosystem.
Water-based gravure printing is also beginning to catch on in the Indian subcontinent for printing on paper and films. We know of several flexible packaging converters who are experimenting and using the new process but are still reluctant to speak publicly about their successes and the challenges they are facing.
From the brand owners’ perspective, water-based inks are more about green chemistry and in alignment with their sustainable initiatives. From the converters’ point of view, better gravure presses in good condition and with the appropriate drying systems that can match the speeds they achieve with solvent-based systems are needed. Many are still using machines that are designed and intended for use with solvent-based systems in which the better release of water-based ink from the cylinders and their drying and curing becomes an issue.
One converter explained to us that water-based gravure printing works better at higher speed in the sense that less moisture or water is needed and, hence, the entire process, including drying, becomes more efficient. However, in order to maintain the efficiency of production at 400 meters per minute, certain modifications need to be made to many of the presses already installed in the field to make them compliant with water-based inks.
However, there is widespread interest in this technology both because of the high cost of solvents and because solvent-free or less solvent printing is healthier and more environmentally sustainable.
Most of the established flexible packaging printers and converters who supply packaging materials to large consumer product brands have already done away with toluene-based inks, but they are reluctant to abandon the solvent-based systems that provide ease of use, good adhesion, and curing. Nevertheless, water-based, inks, adhesives, and coatings are making inroads and are likely to gain traction once the gravure printers and converter gear up their presses or buy new presses specifically designed or capable of this process.
They will also need to change over to the required cell structure in their cylinders and gain more overall experience in the process. With the engraving parameters for better release of water-based inks, these cylinders are currently more expensive than the usual gravure cylinder designed for evacuating solvent-based inks.
However, whenever a new technology is introduced, the brands in India are generally not ready to pay a higher price as they are themselves in an extremely competitive situation with their consumers. Nevertheless, the packaging industry is moving ahead in the right direction. Experts say that the switch to water-based inks is a collaboration between cylinder manufacturers, ink manufacturers, machine manufacturers, and converters. New technologies, investments, knowledge management, and new kinds of equipment and setups are required. But water-based gravure printing is gaining ground and the early adopters are using imported presses that are already equipped to print at high speeds with effective curing of water-based inks.
Brands and converters are gradually migrating from solvent-based inks to water-based inks because they are eco-friendly, have low volatile organic compounds, low GSM, and low ink consumption, possibly leading to ink savings of up to 20%. These more sustainable inks can comprise specially treated water and isopropyl alcohol (IPA) in a ratio of 50:50, and, thus, have a low solvent evaporation rate so that ink is not wasted. Since water is present in substantial amounts, the risk of fire is also reduced drastically. Another advantage is that these inks require no primer, which results in better mileage.
Several leading converters have substantially moved over to water-based gravure and they believe that water-based applications are slowly gaining momentum. Several who are experimenting with this technology have already ordered the appropriate presses, which will make the process more efficient in both the transfer of ink and its drying. These higher-speed machines will make the process even more viable. Hence, water-based gravure applications are on their way to becoming value-added cost-effective solutions that will likely improve in quality and printability.