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Dr Carolin Struller, KTP Research Associate, Bobst Manchester,
speaking about AlOx coated transparent barrier films and their
conversion for
packaging applications, at the Castello di Uviglie.
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True to its
reputation as an innovator focused on creating value to satisfy the different
requirements of converters in a constantly evolving industry, Bobst addressed
the latest trends in new barrier technologies and short run gravure printing at
a conference and open house held on 28 and 29 October 2014 in S. Giorgio
Monferrato, Italy.
150 guests
attended the event, held in the historic Castello di Uviglie in the Monferrato
hills, and heard about the latest developments from a line-up of speakers
including Bobst experts and representatives of leading international companies
from throughout the flexible packaging value chain. The speakers addressed the
challenges and opportunities that the latest materials, systems and production
tools represent to the growth strategies of printing and converting companies.
New barrier
technologies are developing at a very fast pace and a new generation of clear
films and coatings are challenging more traditional barrier packaging
structures. As regards the
technicalities of manufacturing and the physical properties of these new
materials, the presentations from Bobst Manchester and Reifenhäuser were
particularly insightful.
Dr Carolin
Struller from Bobst Manchester, illustrated the company’s in-depth research on
AlOx clear coating, from the way it is produced and its performance on various
filmic substrates, through to its barrier retention with subsequent processes
of printing and converting. Bobst Manchester has, and continues to, carry out
extensive trials on the process and is researching ways that in the future
could enhance their printability and prevent barrier loss during converting.
Kurt Freye and
Daniele Cerizzi from Reifenhäuser Kiefel Extrusion and Reifenhäuser Cast Sheet
Coating presented the latest developments in blown film and cast extrusion for
high barrier applications which reflect the trend for lower pack weights yet
with increasing pack performance. This makes 9 to 11 layer films an important
trend which has generated several ongoing projects for machines which can
produce increasingly sophisticated multi-layer structures using less material.
Paolo Serafin, for
Taghleef Industries, presented their EXTENDO film applications, offering
solutions for better recycling. He also advocated that the day should to be a
forum for discussion and cooperation within an industry aiming to find
solutions for reducing the environmental impact of packaging.
As regards short
run gravure printing, Stuart Jones of Janoschka spoke about the innovations the
company has been working on in rotogravure sleeve systems, as well as on the
retail trends for mass customization.
Professor Armin
Weichmann, from Stuttgart Media University, illustrated the studies that the
institute is carrying out on conductive layers, cylinder stability and the
feasibility of nickel to replace copper and chromium in engraved cylinders. The
professor also spoke about how the Rotomec MW 60 gravure press installed in the
university press room is a key part of all its projects because it nears
productions conditions - something which is essential for the validity of the
trials carried out on the behalf of converters.
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Demonstration on the MW 80 gravure printing press
for very short runs in Bobst Italia's Technology Center. |
The gravure
technology update was rounded up by Giovanni Caprioglio from Bobst Italia, who
illustrated the comprehensive range of Bobst gravure presses for flexible
materials, focusing on the Minimized Waste concept of the Rotomec MW 60 / 80
press. Dedicated to very short run printing, the Rotomec MW 80 brings together
all the essential requisites for profitable operation, namely minimized waste
of material, minimized energy consumption and minimized space requirement.
Of great interest
to all participants was the insightful presentation of Philippe Roulet from
Nestlé, who illustrated all the factors that determine the way packaging needs
to evolve in order to better respond to the new and diverse requirements of the
consumer. Breaking the rules, generating value for the consumer, streamlining
and standardizing the structures of materials wherever possible, and
implementing new technologies into processes were just a few of the key issues
presented.
After lunch at the
castle, the action moved to the nearby Bobst Italia production plant.
A press completely
operated from floor level, the 850 mm web-width Rotomec MW 80 awaited the open
house guests in Bobst Italia’s Technology Center and was ready to start
printing a demo job on a 12 micron PET substrate coated with AlOx.
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Job changeover on the Rotomec MW 80 gravure printing press.
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One highlight of
the gravure demonstration was the capability of Bobst technology to handle AlOx
coated substrates which, in differing from conventional films, present
challenges to printing and converting equipment. A further highlight was the
effectiveness of the MW 80 on-board washing system. The print run also showed
the validity of the Bobst MW Minimized Waste concept, starting with the TAPS
function to set the machine in register. At the completion of the TAPS
sequence, which lasted a few minutes, the screen on the machine registered
incomparably low substrate waste.
After an automatic
splice, carried out on the rewinder at maximum speed, a print sample master was
collected before changing the color on one print unit from light peach to very
dark brown and resuming printing at full production speed. The speed of
changeover being very critical in terms of profitability when printing very
short runs, an operator demonstrated how fast and easy it was on a print unit
which was in stand-by during printing. After a few minutes of printing, the
machine was stopped and the washing sequence of the cylinder and ink pan
started on a selected print unit, prior to the ink being changed back from dark
brown to the original light peach color.
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Demonstration of solvent-based lamination on the CL 850D
duplex laminator equipped with flexo coating trolley.
|
Guests followed
the on-board washing sequence from animations displayed on a screen, whilst
also being able to check on a separate screen the register accuracy and
stability, most particularly during acceleration and deceleration. After
another automatic splice at maximum production speed, the machine was stopped
and a second sample taken in order to measure the color difference with the
print sample master. The Delta E value between the two compared samples was
very low, clearly showing the efficiency of the Bobst internal washing system
in avoiding contamination from one color to the other, especially considering
the great difference of shades in reverting back from a very dark brown
intermediate color. Once the demonstration was over, guests were able to get
close to the machine to visually see the results of the washing sequences from
the ink pan and cylinders which were taken out of the MW 80 press for checking.
A demonstration on
the Bobst CL 850D, confirmed the laminator’s quality, efficiency and
flexibility. The machine, featuring the renowned Bobst flexo coating system,
laminated a 7.0 micron aluminium substrate onto a 12 micron PET film. The Bobst system enables a lower coating
weight of solvent-based adhesive to be applied directly to the aluminium foil,
creating excellent bond strength. The machine produced a flawless, high
quality, duplex laminated structure at a speed of 430 m/min.
The event ended
back at the historical Castello di Uviglie with cocktails and dinner.
