1.- What does EB stand for?
EB means Electron Beam.
2.- What is EB curing?
In EB curing, a curtain of accelerated electrons is emitted towards the web in an evacuated chamber. The highly energetic electrons pass through a titanium window foil towards the web in a nitrogen inerted process zone. When the energetic electrons hit the wet ink or coating, the energy is absorbed by the ink layer and the curing process takes place, instantaneously without the need for a photoinitiator.
3.- Is EB technology a new concept?
EB is not new. It has been used in the offset printing industry for decades. EB cross linking of high barrier shrink films for food packaging applications has been commercial for several years. EB sterilization for the pharmaceutical and bio medical device industry is a well established process and has been commercial since the sixties and seventies.
What is new is the usage of EB process for the flexography industry and the flexible technology with a proven industrial solution. The name given to it is: “e-COMEXI”.
4.- What does e-COMEXI stand for?
e-COMEXI the new Comexi’s brand to describe the portfolio of solutions which cover the EB flexo printing, EB coating and other EB-driven technologies in order to increase the final added-value of the packaging in a sustainable and VOC-free manner.
e-Comexi strives to support and develop ´green technology´, reducing the use of VOC´s (Volatile Organic Compounds) like solvents and help to reduce the emission of Green House Gasses (GHG).
An EB press reduces the carbon footprint to about 1/3 of a conventional press (only electricity load). Investments in incinerators are obsolete with EB technology.
5.- Are UV and EB system the same technology?
From the curing point of view both of the ink systems use an external radiation energy source. The UV radiation is not powerful enough to start the polymerisation process and requires the help of a photoinitiator. EB inks do not use such photoinitiators since the electrons can start the reaction by themselves. Therefore the EB inks are potentially cheaper.
6.- What are the differences between UV curing and EB curing?
- UV Curing
- Excellent print quality
- VOC free inks
- High Rub and chemical resistance
- Use of photoinitiators (PI's)
- High Cost
- Food compliant ink series extremely costly
- Face restricted level of acceptance with Brandowners
- Several degrees of curing are seen
- No autocleaning possible (time and cost)
- Wah up with solvents (health)
- Very high viscosity (500 - 1000 mPas)
- EB Curing
- Excellent print quality (same Q as UV inks)
- 100 % VOC free process
- High Rub and chemical resistance, High Gloss
- No Use of photoinitiators (PI's)
- Same integral Cost as SB inks
- Food compliant inks by nature
- Enjoy increasing interest with brandowners
- No degrees of curing are seen. On or Off
- CI Autocleaning possible (time and cost)
- Wash up with water (health and waste savings)
- Viscosity like SB inks (120 - 280 mPas)
7.- Is EB a safe technology?
It is a perfect safe technology and in use already since the 60-ties. The electron beam equipment is an electrical apparatus which can be switched on and off.
The elimination of any solvents in the operations, means a safer labour environment and a reduction of insurance cost. EB treated materials do not show any systematic toxicity and are not carcinogenic.
Print jobs have been researched by known food safety test institutes (like e.g. Fabes in Germany) and all provided samples have passed the compliance requirements to food safety. However, it must be noted that it is advised that the responsibility remains with the printer to execute according good manufacturing principles and file for food compliance certificates.
8.- Is there any radiating equipment?
When electrons hit metal, X-ray radiation is emitted. Therefore, the equipment is covered in a stainless steel and lead shielding to absorb the X-ray energy. None of this radiation is emitted outside the process zone of the EB equipment. It is not a hazardous equipment. EB equipment is electrical, and when it is off there are no electrons or X-rays emitted.
9.- Has EB Flexo technology an instant curing?
Yes, the cure achieved is instantaneous and effective. It enables the printer/converter to post process like coating or lamination in-line. There is no cure time and one can slit and ship immediately after coming off the press. The EB technology enables JIT (Just in time) printing and converting that significantly shortens the time to market.
10.- What is nitrogen for?
The process is under an inert atmosphere of nitrogen. The air that we breathe contains 78% nitrogen, but is not pure enough as the oxygen in the air inhibits the curing process and result in the generation of ozone. To increase the efficiency of curing and avoid the generation of ozone, the treatment process zone needs to be maintained with oxygen levels below 200 ppm (part per million).
12.- Will the system impact on cost per produced square meter?
Ink cost has a significant impact on the final cost. Although energy curable inks are higher in cost per volume unit, the consumption is much lower. The offset balance is cost neutral, otherwise the system could not be commercial attractive.
Detailed cost calculation models are available to calculate accurately the T.C.O. (total cost of Ownership). The model is parameterized flexible and to dedicate it to your specific situation in your company. It gives a clear insight in the cost, comparing solvent base printing with EB.
14.- What is the maximum printing speed for a industrial EB Flexo process?
The speed of the curing process is subject to the energy dose. For print processes, a dose level of 30 kGy is used. This energy can cure wet inks to up to 400 m/min (1300 ft/min). The ink system is based in wet-in-wet trapping, whereas the viscosity is trapped to secure a sequential lay-down wit. At present, Comexi is leading the development process of EB technology hand in hand with Sun Chemical and ESI. Speeds up to 350 mpm are consistent in print quality. In the months to come, Comexi, Sun Chemical and ESI strive to increase even further improved performances.
15.- What do Brand-owners feel about this technology?
Brand-owners are on the continuous look out for innovative solutions to differentiate themselves. Improvement of print quality, shorter time to market and lower cost are continuous key drivers. EB technology ensures the compliance to these drivers, but moreover address the growing attention to reduce their carbon footprint.
If a new technology can improve quality, shorten time to market and support the print industry with a sustainable solution WITHOUT increased cost, brandowners show appreciation and a growing interest.
16.- How can I test the e-COMEXI technology?
Nowadays we are mass-producing the first e-COMEXI press, the E-COMEXI FW1508. Starting in February 2010, we offer the opportunity to carry out industrial runs in our R&D Centre on a full EB equipped press. A first-class production environment will be provided, with state-of-the-art technology for our customers. Contact our sales representative in your country (go to “Sales” area in the corporate web site) or email at email@example.com