smartGravure prepares gravure printing for the future

As part of its industry vision, Bobst has set out to take packaging production to the next level by making it increasingly digital, automated, connected and sustainable. With smartGravure, the Swiss group is bringing this vision to gravure printing.

Bobst has been developing and manufacturing gravure presses for more than 80 years. No other manufacturer offers a comparably broad portfolio of machines for this printing technology, covering such a wide range of applications and requirements. “As a world-leading supplier of gravure printing platforms, we clearly had a particular interest in bringing this process into the 21st century. With smartGravure, we have achieved that, taking inspiration from digital printing,” explains Marco Schmidt, Area Sales Manager Flexible Packaging for the DACH region at Bobst.

The company developed the new solution for its Master 6003 gravure press platform, combining a range of innovative, precisely coordinated hardware and software components in a comprehensive approach. The modular system comprises three packages: oneECG (Extended Colour Gamut, or ECG), oneSET and onePrint. These advanced technologies fully digitalise the traditionally labour-intensive gravure process, reducing its complexity while retaining all its advantages.

Moving gravure beyond its niche

With smartGravure, gravure printing combines premium print quality, high production speeds, process stability and repeatability with short makeready times and rapid job changeovers. Packaging printers can therefore now use the process profitably for short and medium runs as well. smartGravure also significantly improves sustainability in gravure printing, notably by substantially reducing ink consumption, ink waste and substrate waste, including start-up waste. Together, these developments enhance the process in ways that would have seemed almost inconceivable until recently. “With smartGravure, gravure can compete with other printing processes, such as flexo and digital, in packaging production and fully exploit its particular strengths. That was the benchmark we set ourselves when developing smartGravure. And we have achieved it,” says Schmidt.

The highly flexible and energy-efficient Master 6003 is the flagship of Bobst’s gravure press platforms. It can be configured for specific applications as a multifunctional production line, accommodating different packaging printing requirements, including a variety of inline converting processes. smartGravure likewise gives Bobst customers the flexibility to choose either the complete solution or individual modules.

The world’s only Pantone-validated gravure platform

With oneECG technology, the Master 6003 prints with a fixed ink set of up to seven colours, covering a wider colour gamut than conventional CMYK printing while maintaining exceptionally high colour stability. This represents another pioneering development by Bobst in packaging production.

To remove any doubts in the market about the colour stability of its oneECG gravure technology, Bobst commissioned Pantone to validate it through extensive, rigorous testing under a wide range of extreme conditions. Pantone supplied more than 2,300 Pantone spot colours for the test. Bobst’s prepress team produced separations for all of them, and they were printed in a single pass on the Master 6003 using oneECG technology. Pantone then analysed and measured the printed samples. The approach proved successful: the US company confirmed the colour accuracy and quality achieved by Bobst. The Master 6003 is thus the world’s first and only gravure press to have been fully validated by Pantone for fixed ink set printing.

“This gives our company a unique position in the market,” says Schmidt. “The validation gives our customers the highest level of assurance that, when producing packaging for brand owners on the Master 6003, they can reproduce more than 96% of the colours in the Pantone guide using the seven colours of oneECG technology.”

Fixed ink set printing brings further benefits to gravure. Packaging printers need fewer printing cylinders and only have to stock a maximum of seven inks for this process. The spot inks previously required, and the disposal of unused residual ink, are eliminated. At job changeovers, only the printing cylinders are replaced; the inks remain in the press. Changeovers are significantly simplified, while ink and substrate waste are minimised. “By up to 50% when combined with the other two smartGravure packages, onePrint and oneSET,” Schmidt adds, quantifying these process improvements.

onePrint supports high colour stability

The onePrint automatic inline colour control system also plays a decisive role in maintaining high colour stability on the Master 6003. An inline spectrophotometer continuously measures the process colours, whether CMYK alone or the oneECG ink set. Whenever they deviate from the specified parameters, the system automatically corrects them in a closed control loop. This ensures reliable colour stability from the first impression to the last.

Another key feature of the new inline ink system is that it limits the volume of ink in the Master 6003’s ink circulation system to the minimum required: less than 50% of the volume used in conventional gravure printing. In concrete terms, Bobst has reduced the volume from the 23 litres typically required previously to 9 litres. This is a further reason why smartGravure produces significantly less ink waste.

Gravure press settings can now be prepared offline

The third package in the smartGravure system is oneSET. This solution fully digitalises and automates the setting of printing parameters on the Master 6003. Using the PDF files for customers’ jobs, oneSET automatically proposes the most suitable and efficient press settings, including dryer temperatures, web tension and printing speeds. Previously, these settings had to be entered manually at the gravure press on the pressroom floor, creating the potential for input errors.

oneSET moves this step into prepress, where job recipes can be prepared offline and checked for accuracy. They can then be transferred to the Master 6003’s job queues with a single mouse click. In this way, oneSET minimises gravure press downtime during job changeovers. “Customers using the complete smartGravure package can reduce their downtime by up to 70%, significantly increasing press availability,” says Schmidt, providing another specific figure.

oneSET forms part of the Recipe Management functionality in Bobst Connect. Recipe Management automates makeready on Bobst machines connected to the Swiss group’s cloud-based platform for digitalisation and connectivity. These machines can send production data to the cloud and receive settings and data for process improvements during production. The days when they operated as isolated units are over. With oneSET, the Master 6003 gravure platform can also be integrated into the comprehensive optimisation of packaging production through Bobst Connect.

Packaging printing for today’s requirements

Printing with a fixed set of inks that remain permanently in the press, automatic inline colour control in a closed loop, and fully automated printing parameter settings are characteristic capabilities of digital printing that have helped establish its successful future.

With smartGravure, Bobst has integrated these capabilities into the analogue gravure process, creating an end-to-end digital workflow. This enables gravure to meet current packaging production trends in ways previously unavailable, including the efficient, profitable production of shorter runs of packaging in different colours and sizes, with exceptionally high colour stability.

At the same time, the increased availability of the Master 6003 with smartGravure delivers significant productivity gains in packaging printing, shift after shift. Another aspect is becoming increasingly relevant as the shortage of skilled staff intensifies: smartGravure enables packaging manufacturers to reliably achieve the premium quality demanded particularly by brand owners, irrespective of their press operators’ experience.