A new solution for short runs and fast delivery times
This Drupa, Uteco launched the Onyx XS EcoOne production line. The machine combines EB flexo printing,coating, EB laminating and slitting on one unit and accelerated the production process for certain applications. Flexible Packaging Technology spoke with chief product manager Alessandro Bicego about Uteco's latest development.
In the EcoOne, Uteco has linked four process steps (printing, coating, laminating and slitting) together. This was made possible by using direct curing EB adhesives which enables to slit inline after lamination, instead of having to wait for 24 hours, which is standard when using other adhesive systems.
The main advantage of this system is that it shortens delivery times. As EB inks and adhesives cure right away, printing, laminating, and slitting a 5000 meter job can be done within 20 minutes (excluding make ready) and is then ready to be converted into pouches or shipped to the customers FFS lines, instead of one or two days - depending on the bond time of the adhesive used and job planning. Depending on the job and if white substrated is used the line has a production speed of 300 m/min, for this printing press.
Time saving isn't the only advantage the Onyx XS EcoOne is said to provide. An all-in-one line consumes less energy than a EB flexo press, a EB laminator, and a slitter rewinder combined. According to Uteco, the achieveable energy savings are at about 70%. Similar is true for the possible space savings as the footprint of the Onyx XS EcoOne is much lower than that of three individual lines.
Another area where significant savings are possible is start up waste, since only one line has to be set up, up to 70% less waste is achievable. Uteco says that in many tests they confirmed this number. Alessandro Bicego: "Of course, as more factors and parameters are involved than with just a printing press, the produced waste is a bit higher, but much lower when compared to setting up a printing press, and a laminator, and a slitter rewinder."
Combining three lines in one also affects the operator. For once, less manpower is required to run one line instead of three, but the requirements on the operator are higher since he has to be an expert in EB printing, EB laminating, and slitting and rewinding.
Electron Beam technology
There are only few technologies in the flexible packaging industry which have received that much media coverage in the past some years as EB flexo.
When being introduced to the market, EB flexo was said to have similar if not better properties than UV, but without the well known deficiencies in terms of curability and what results from that.
Typical solvent or waterbased inks contain about 40-60% solid components, including pigment, resins, and additives. EB inks on the other hand are 100% solid which means less spreading on the substrate, lower dot gain and higher reproducability.
EB inks have a higher gloss , colours are brigther and higher in contrast and enable to print smoother vignettes. What's more is that higher solid ink densities are possible and abrasion and resistance is higher.
EB enables to use anilox rollers with a higher linature which subsequently enables to use printing plates with a higher lineature.
The consumption of EB inks is more than 50% lower when compared to solvent or waterbased systems. Furthermore it is claimed that the energy consumption to cure/dry the ink is way lower as there are no interdeck dryers. This also reduces the noise level significantly.
EB is also considered a greener system since no solvent emissions are created there is no need for distillation and or combustion. It is said to be easier on the operators health and safer to handle, and also lower insurance costs. Since it is a relatively cold process, no extra cooling of machinery is required.
When using fixed colour pallete printing some benefits of EB flexo inks can be further employed such as being able to leave the ink in press.
Long development work
Uteco is developing the EB technology now for more than 10 years and believes to have solved the problems associated with this technology. Due to technological advancements Uteco says that the ink doesnt get dirty in long runs anymore. Previously there had been reports that the wet, uncured ink "travels" via the substrate from one printing unit to the other, causing the ink to get dirty. Running EB inks in a flexo press requires many modifications. Uteco has developed Thermilox,a temperature controlled anilox sleeve, and modified the ink circuit to eliminate foaming. For instance, the Onyx XS EcoOne has modified ink pumps, ink hoses, a patented doctor blade system and the ink pressure and viscosity are controlled on a constant base. Alessandro Bicego: "We have made more than 500 tests in the last some years and can now say that EB flexo is a stable process."
About two years ago an Italian printer has installed an Onxy EB flexo press with all the advancements Uteco has made. It is reportet that this company prints shopping bags in long runs at up to 400 m/min.
So where is the catch one might ask? Even if all issues associated with EB had been solved, only if at least one customer successfully used this technology the reservations towards EB will still exists. In theory it sounds like a beneficial technology, but it is about time that we see EB flexo put to good use in practice.
As soon as this happens, more ink manufactures should start producing their own EB flexo inks, which was another hinderance for many printers.
As for the cost of the line, as with everything a purchase decision should be based on the comparison of the comprehensive cost and performance analysis. When one has plenty of short runs with very short delivery times, and the type of jobs that can employ the benefits of EB, this line might be a good solution.
According to Alessandro Bicego, EB is considered as solution for nice applications with special demands on a high quality or very short converting time. He said that Uteco has received numerous requests during Drupa and their open house event, and that soon we can expect the first installation of this line.