Siegwerk adds EB offset inks for flexible packaging

Offset printing inks are used in a number of flexible packaging and label applications, such as shrink film, wraparound labels and IML, with UV-curable inks successfully used in many cases. By using electron beam (EB) curing, converters can avoid the use of photoinitiators in energy curing inks and reduce the risk of potential migration problems.

The new ink technology has been 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. Siegwerk’s own migration tests with trial materials exhibited low migration behavior suitable for food packaging.

With its new EB offset inks, such as EB 705, Siegwerk said it is giving flexible packaging printers access to the benefits of offset printing for short print job lengths, including low cost of print form and short set-up times allowing for quicker changeovers between print jobs.

Industrial print trials on Comexi’s CI8 central impression EB offset press have shown Siegwerk’s new EB technology offers ‘excellent print performance, low dot gain, low water dosing with less emulsification and scumming’, it is claimed, as well as fast intensity recovery after stops. The new ink technology is suitable for a variety of plastic substrates of the flexible packaging market like co-extruded OPP and acrylic coated PET. The first positive results have also been obtained in lamination studies with different packaging structures.

Dr Stefan Busse, regional director of application technology for flexible packaging in the EMEA region at Siegwerk, explained: ‘In the past, typical print run lengths for example in beverage wraparound labels were several tens of thousands of square meters.

‘Today, more and more jobs are printed on wide web machines with only a few thousand square meters. In order to stay cost-competitive in these markets all cost drivers have to be minimized. That’s why some of our customers are attracted by the low cost of print forms for offset printing plates.’

Siegwerk was invited to supply EB offset inks for Comexi’s recent Open House event on December 14th in Girona, Spain, where the CI8 press was presented to a selected audience. ‘We are proud of the acknowledgement of our ink performance by Comexi,’ commented Busse. ‘During the last month our technical teams in Europe have made any effort in finding ways to help our customers accessing the benefits of offset printing in flexible packaging.’