Fujifilm’s Uvijet ink in magenta
With growth in inkjet press installations pushing into all areas of digital packaging, developments in inks for this particular technology must follow suit. By Neel Madsen.
In inkjet for labels, UV-cured ink is the more established technology, with water-based ink for corrugated seeing considerable uptake in the past couple of years and flexible packaging remaining a challenging application.
‘Hardware, particularly printheads, has evolved sufficiently that it can meet the market needs for image quality and print speed, and it is now the availability and suitability of the inks and coatings that are required to fully enable the adoption of inkjet printing on an industrial scale for packaging markets,’ stated Peter Saunders, business director for digital at Sun Chemical.
Siegwerk’s Matthieu Carni, who is director of the business unit for inkjet, commented, ‘I strongly believe that UV inkjet will become a mainstream printing technology for label applications. I also expect some long-term opportunities for UV inkjet especially in the direct-to-pack printing market where we are still in an early stage of the adoption curve.’ He continued, ‘Water-based inkjet inks are naturally offering great opportunities for corrugated printing applications. I also expect this technology to become the technology of choice for digital printing of flexible packaging. Even if there are some significant technology barriers that still need to be overcome, I expect first developments of water-based inkjet inks for flexible packaging to be announced around drupa and Interpack in 2020.’
Inkjet expansion
Siegwerk Druckfarben made its move into the inkjet ink market a few years ago, and now offers conventional inks to printers and inkjet inks to equipment manufacturers for packaging and label applications.
The company has continuously invested in the expansion of the digital printing segment to create a solid base for significant commercial success, according to Mr Carni. He said, ‘The recent acquisition of Agfa’s UV inkjet ink business for labels and packaging will further boost our business by extending our global reach in this young market segment. Herewith, we clearly strengthened our footprint in digital printing and paved the way for an even more successful year.’
Over the last three years, the company has invested €3 million to build its development, production and testing capabilities in inkjet technology. After opening a dedicated inkjet laboratory in 2016, it introduced the first designated inkjet ink production facility in 2017, and plans to invest an additional €2 million in new equipment over the next two years.
Mr Carni said that the most promising technologies are UV inks for narrow web printing in labels and direct-to-shape, while water-based inkjet is the most promising technology for single pass large width printing on flexible packaging and corrugated applications. ‘We offer customised ink solutions to the users’ needs – this means for the final application and not only for a given printing equipment. For us customisation goes beyond classic colour matching, it also covers optimisation of adhesion, mechanical and chemical resistance as well as assessment of migration risk,’ he explained.
The deal with Agfa means that Siegwerk is now able to support OEM partners, in other words machine builders and equipment suppliers, with specific application expertise and a broader market access. Mr Carni said, ‘By merging the two inkjet portfolios, we are extending our offer for a wide range of applications, including self-adhesive labels for household, hygiene and industrial packaging, wet-glue labels for beverages, direct printing on 3D-packaging objects or blister and aluminium lids for pharma and food products.’
A wide range of colours for various applications is available from Siegwerk
Bespoke inks
The Armor Industrial Inks Lab is one of four business activities of the Armor Group. Based in Dortmund, Germany, with an ink production plant in Prudnik, Poland, it was founded in 2016 as an evolution of Armor’s inkjet development and production business unit and serves a broad variety of industries from décor printing to the fashion and food industries.
The focus of the Industrial Inks Lab is to serve clients with inks that are individually designed to fulfil or exceed the client’s expectation of requirements regarding the ink performance.
All inks are water-based, a strategic decision made in line with the strong commitment to sustainability of the company, but this does not necessarily limit the choice of substrates for the customer. Senior marketing manager Lars Strzeletz explained, ‘In today’s perception and understanding of the industry, water-based inks are nice but limited when it comes to the range of suitable applications. However, when we show our print samples to our partners, they are surprised – none of them believed it would be feasible to print for example onto non-porous substrates with a water-based ink.’
The bespoke design process follows the ‘outside-in’ principle: before any development takes place, the team of ink designers assess the needs of the individual client and scrutinises the print production environment. Mr Strzeletz said, ‘The designers go far beyond the printer and its printheads when investigating the printing environment: any factor which has a direct or even a lateral impact on the printing quality is taken into consideration to ensure the ink creation performs perfectly in its destined production environment.’
After this initial investigation, the designers return to the lab and start designing an ink that fulfils the client’s requirements under the given conditions. Next step is an internal ink testing procedure, conducted by in-house application managers. If the ink performs satisfactory in all categories, it is presented to the client for approval and forwarded to the production plant in Prudnik for volume production.
Armor is in the process of building an industrial inkjet test printing machine, which will be based in the new showroom in Dortmund. This single pass machine will put the team in the position to simulate real industrial inkjet production runs for any printheads and substrates.
Product manager Michael Wartmann commented, ‘With our new showroom and our unique industrial printing machine, we are aiming at nothing less than creating and setting our own Armor standard for the creation and approval of digital industrial inkjet inks. The machine we are going to install is a six-digit-budgeted single pass printer we have developed entirely on our own. It allows us to adjust any factor which impacts the print production at our client’s site.’
Combining strengths
Sun Chemical offers inkjet inks through its SunJet brand. ‘As digital technology alters the packaging and narrow web printing landscape, we’re leading developments into new inkjet and coating technologies for emerging sectors of the packaging and label markets by combining our strengths and long-standing experience of both analogue and digital technologies,’ said Peter Saunders, business director for digital.
He continued, ‘Inkjet as a technology continues to evolve, but the earliest adoption in packaging was probably in the label industry, which led to the need for migration-compliant inks for food applications, such as the award-winning Etijet ULM ink from SunJet.’ This range of low migration inks is compliant with the Swiss Ordinance and Nestlé Standards and formulated and manufactured in accordance with the EuPIA Guidelines. However, Mr Saunders said the economic viability of electron beam (EB) curing will probably mean that EB technology will become the preferred option for future applications in this space.
The demand for water-based inks is mostly driven by food packaging compliance, but also lower (than UV) ink cost for high volume production. Mr Saunders explained, ‘The challenge for aqueous inkjet inks arises in being able to deliver the level of performance required during jetting and on substrate. By comparison, UV inks have good in-printhead performance and offer a robust film onto a wide range of substrates.’
SunJet’s Aquacure functional aqueous technology has been designed to bridge this gap by combining the strengths of water-based and energy-curable technologies. The process of printing, drying and then curing ensures that there is good open time in the printhead and that the low build prints are suitably robust once cured, while maintaining compliance with food packaging regulations.
However, most current developments in packaging feature water-based inkjet ink in combination with the interventions of analogue applied primers, adhesives, coatings and varnishes. Mr Saunders said, ‘Sun Chemical has recognised the need for coatings to help unleash the full power of digital printing for both inkjet and electrophotography techniques by launching the SunEvo range of digital coatings for flexible packaging, labels, folding carton and corrugated.’
Corrugated and cartonboard printers may use several substrate types with varying properties. To achieve adequate image quality on all substrates, a primer can be applied to create a more homogenous surface to print the aqueous inkjet ink on. These boards are then often finished with analogue over-print varnishes to meet exact gloss, slip and scuff resistance.
For flexible packaging, the variety and complexity is even larger as there is reverse or surface print on a huge range of filmic substrates, some of which are subsequently laminated. Having customised analogue primers, varnishes and adhesives for each chosen application will therefore make inkjet production possible. Mr Saunders concluded, ‘The only practical way to overcome the variety and complexity in packaging is by combining analogue and inkjet expertise.
Value from innovation
Tudor Morgan, sign and display segment manager, Fujifilm Graphic Systems Europe, said, ‘Fujifilm is developing new inks all the time, each and every one of them carefully designed to exacting standards. Aside from quality, compliance is the other key. Whether it is emissions compliance for indoor graphics, or food safety compliance for packaging and food retail displays, regulations in this area are stringent.’
The company developed its Vividia aqueous ink for the Jet Press 720S, of which there are more than a hundred installations globally. The flagship B2 inkjet press is now widely used for folding cartonpackaging. Mr Morgan said, ‘Using the high performance Vividia inks, which, being water-based, means that the Jet Press 720S requires less cleaning and produces less waste. Our customers are creating a variety of short-run and prototype packaging for a range of products including pharmaceuticals, toiletries and cosmetics.
For the Onset X press, Fujifilm has the Uvijet LM series. The pressis now starting to see success in the corrugated display and packaging markets, thanks to this new low migration UV ink, which is opening up opportunities in secondary packaging and in corrugated retail displays for food products. Showcased at Fespa 2018, the UV ink system is compliant with the Swiss Ordinance and is already in use by several European customers, according to Mr Tudor.
Fujifilm’s Uvijet UV imprinting inks are used on theretrofittable Fujifilm Samba 42000 Inkjet Printbar to help flexo printers meet the growing demand for label customisation. Available in black, white and clear as standard, with spot colours available on demand, the inks print to a wide variety of label substrates ‘with excellent adhesion, light fastness and durability.’ The range is available in both general purpose and low migration ink series, and can be cured using either conventional or LED systems.
Mr Morgan concluded, ‘The future of ink production at Fujifilm lies in building on these successes and others like them and to continue to push the boundaries, innovate and do things no one thought possible.’
Toners
The toner market in labels is dominated by HP and Xeikon, which each has dedicated products for their presses.
HP continues to expand the ElectroInk range for its Indigo labels and packaging presses, claiming to offer the ‘widest colour gamut in digital production.’ This is in fact a liquid toner rather than an ink, with the most recent additions being ElectroInk Silver, Fluorescent Pink and a new white as well as invisible inks for security applications.
Xeikon uses dry toner electrophotography, which can print on most types of substrate without any pre-treatment. These are all food-approved, complying with FDA guidelines for indirect food contact and direct contact with dry food substances that contain no oil or fat. The range includes the QA-I, ICE and Cheetah toners.
