Siegwerk launches new generation PUR inks

Packaging Solutions

Siegwerk now offers an innovative ink system for gravure printing based on polyurethane (PUR). The new technology delivers excellent print results, while also enabling printers to simplify their portfolio, improve processes and reduce operational costs.

‘Lately brand owners have expressed an increasing interest in PVC free printing inks to realise complex packaging structures. Our new PUR based ink system fulfils these requirements, while also incorporating other benefits,’ explained Dr Hanns Martin Kaiser, head of Technology Flexible Packaging EMEA.

The new ink technology is optimised to meet high performance requirements – such as high bond strength values in lamination. It allows for use in harsh retort conditions and can also be applied on modern barrier film substrates.

Another benefit is that the PUR ink system is solely based on ethyl acetate as a solvent to allow utilisation in monosolvent set ups in combination with solvent recovery systems. The key polyurethane binders are manufactured in Siegwerk’s own PUR production facilities in Annemasse (France) or Bhiwadi (India).

‘After two years of development, the new ink range performed very successfully in first extended industrial trials. It showed excellent printability with solid full tone and outstanding half tone reproduction. We optimised it for best dispersion results in order to produce high colour strengths,’ said Hanns. Under industrial trial conditions the new PUR inks exhibited very good printability even at high printing speeds above 500 metres per minute. At the same time, it has been proved that the solvent retention level of the inks is very low.

Furthermore, Siegwerk’s PUR ink solution can also be used for medium performance applications, since it can be supplied in two different versions – either as a master base system in the form of ready made inks or as a master batch system, where the full PUR concentrates are combined with various master compounds (technical varnishes) out of one dispenser.

Siegwerk’s new ink range is a combination of a new technology – the polyurethane binder – with a proven concept – the masterbatch system. This creates a universal platform in terms of print performance, efficient handling in the ink room and cost effectiveness. The inks will be tailored to the specific requirements of each customer to match their individual needs, keep the portfolio simple and avoid overdesign. This contributes to simplify ink room complexity and reduce ink stocks, which at the end improves cost in use for customers.

The new ink technology was developed in accordance with the relevant product safety standards. All ingredients are compliant with the stringent Swiss Ordinance and will also comply with the upcoming new German Ordinance. The new system will add to Siegwerk’s broad range of Flexible packaging solutions – while other ink technologies including PVC based inks continue to have their merits.