Bruckmuehl, Germany - On June 24th and 25th, 2015 the IMI Inkjet Technology showcase conference was held in Munich. During this event a company field trip to adphos Digital Printing GmbH in Bruckmühl near Munich took place to see their drying and InkJet-technology integration . After this a post-conference symposium in a local Bavarian brewery with dinner completed this spring conference.
During the 45 minute bus ride to adphos, an introduction to Bavarian history, its tourist attractions and its cultural heritage was given, as well as a brief profile of the adphos Group, its product portfolio and the wide range of applications of its adphosNIR® technology.
At the adphos headquarters, besides a walk through the manufacturing area, three live demonstrations illustrating the special benefits of adphosNIR® technology were presented.
The first, a comparison of the drying of water based inks on thin plastic films compared the performance of midwave IR drying units with adphosNIR®. It was shown that with identical electrical power, the adphosNIR® dryer reached complete drying of the fluid in one third of the time, whilst even with three times more drying time, the midwave IR sample produced was not completely rub resistant.
In addition, the adphosNIR® demonstrated its instantaneous power adjustment capability, whilst the midwave IR required a start-up of 15 s to reach the nominal drying temperature. It was also seen that the high residual heat of the midwave IR dryer unit caused thermal damage of the plastic film once the transport was stopped, whereas the film was not visibly effected by the adphosNIR®.
The second live demonstration was to show that adphos can successfully dry process colour inks onto film. The drying of simultaneously applied, water based black and yellow pigmented inks with adphosNIR® was presented to the auditorium.
Even though the radiation absorption by black ink is 8 times higher than for yellow ink, both coating layers were properly dried by the adphosNIR®, without damaging the black print pattern. Starting at 20 °C ambient temperature, the temperature after the dryer of the yellow ink was raised to 44 °C whilst the black ink reached
87 °C. This demo clearly proved to all participants, that adphosNIR® can properly dry process color and is totally applicable as a final dryer in color presses and not limited to only monochrome applications.
The third and final demonstration in this short tour was to show that adphosNIR® is also applicable in flexo printing processes. Here adphos showed water based inkjet fluids being dried onto plastic films. Due to the low thermal stress and low heat absorption of the adphosNIR® by the plastic film, water based inks can be applied to these substrates and dried using only the same minimal heat as is usually only possible using UV curable inks.
The highlight of the live demonstrations was the running of a Roll-to-Roll pilot line with a Kodak Prosper S10 Imprinting System onto 35 µm pre-coated OPP plastic film(oriented polypropylene), which was possible due to the use of an adphosNIR® dryer. A 100 % ink weight, print pattern (see photo) was properly dried and rub resistant, yet the OPP was completely un-effected by heat. Thanks to the Kodak Stream InkJet technology with its low glycol content level ink, in conjunction with the special working principle of the adphosNIR® drying technology, high print quality, high coverage water based ink, can be dried onto temperature sensitive plastic films and can therefore substitute UV curable inks in applications where previously this was impossible.
Between the demonstrations, the visitors could also inspect the large variety of standard adphosNIR® dryer modules available enabling a customer to get the highest print quality and performance for an existing application. Whilst walking through the production area, several drying solutions for other business areas served by adphos, such as coil coating, automotive and plastic thermal forming were seen.
This highly informative and educative day was concluded with active discussions on the present and future potential of InkJet printing in a relaxing and refreshing environment of the bar at local Bavarian brewery with a variety of regional foods.