High solvent use in gravure printing is perhaps the biggest hurdle to overcome in order for this sound technology to maintain its strong position longer term. With increased government regulation globally and public opinion favoring new greener technologies, the future opportunities for gravure are destined to be coupled with more sustainable manufacturing technologies aimed at making alternative greener process applications more efficient.
Water-based inks present a long list of benefits and have already been successfully deployed in other printing technologies, including offset litho, flexo and digital. Water-based inks greatly reduce VOC emissions as these most often contain a maximum of 30% solvents in the formula. Not only does this reduction protect our planet from pollution, it also makes for a safer and healthier working environment for operators.
However, until now the use of water-based ink systems has been very limited in the gravure market due to the longer drying times, lower press speeds and poor performance on substrates. But as regulations regarding VOC emissions, especially in China and the SEA regions, are now restricting producers of flexible packaging on the type of inks they can use, there is a push in the market to develop inks without solvent and printing presses that can handle water-based inks efficiently.
Bobst is developing successful water-based applications on its gravure presses, utilizing Siegwerk’s new formulation WB inks. The partnership with the ink manufacturer aims to present ink formulas that will set unprecedented performance and quality levels in gravure printing, and which have much lower VOC content than current WB offerings on the market.
Initially the geographical scope for this project is China, where gravure is a mature and dominant technology, and where the government has introduced particularly stringent regulations. As of July 2020, a trial implementation regarding commodity packaging printing for government purchase in China recommends that the content of VOCs in the ink used is not to exceed 5% by weight, and no more than six colors should be printed on each package. “It is time to rethink packaging and let water-based inks flourish in a circular packaging system. A water-based ink system is a more environmentally friendly and green technology, essential for the future of the ink industry,” commented Jimmy Goh, head of technical flexible packaging China.
“The main objective of the partnership with Siegwerk is to increase the sustainability of gravure printing and enable flexible packaging converters to comply with new regulations,” said Jonathan Giubilato, product line manager gravure. “Sustainability is a core pillar of Bobst’s vision of the future of packaging printing, and it is essential that companies in leading positions work together to advance environmentally-friendly solutions and establish a benchmark for new technologies.”
Bobst is also continually pushing press technology forward to meet and even exceed demands for more sustainable solutions. The Bobst RS 3.0 PLUS gravure press combines high-speed and quality with water-based inks without compromising on quality. It was instrumental in earning Bobst Changzhou a certification as a Demonstration and Training Base for Alternative Applications to VOCs in the Packaging and Printing Industry from the Printing and Printing Equipment Industries Association of China (PEIAC).
The recently launched Bobst Vision RS 5003, which is the next evolution of the Nova RS 5003, a very successful gravure press in the Asian market and beyond, runs at 450 m/min and is fully compatible with water-based inks. Amongst the many features that contribute to more sustainable production are high efficiency, extended twin flow dryers and ventilation system for energy savings, unique winders with energy recovery, and Lower Explosion Limit (LEL) system to avoid emissions into the atmosphere, along with the ability to print on thinner and more eco-friendly substrates. The press also features an increased level of automation, helping to enable water-based, high-speed printing.
“Putting together Bobst’s extensive and long experience in gravure printing press technology and Siegwerk’s strong expertise and know-how in printing inks means that we can deliver a viable and much more competitive solution for WB inks,” concluded Jonathan. “Together, we will lead the way in innovation in water-based gravure, as Bobst accelerates the implementation of our future vision for the packaging printing industry – built on automation, digitalization, connectivity and sustainability.”
