Sheetfed Drying/Curing — A Cure-All for UV Inks
The technotrans america sheetfed division is the exclusive representative for IST Metz UV curing systems for sheetfed applications in the United States and Canada. The company also offers a thermal drying system that doesn’t limit press running speeds and is well balanced with the press delivery to assure optimum drying performance, sheet control and heat management.
IST Metz has introduced several new features and options to its UV curing system offerings. The Cool Cure system allows the UV curing process to take place in an oxygen inert environment. By replacing the oxygen with nitrogen, the efficiency of the UV curing process is increased, resulting in lower required power outputs and significantly reduced temperatures to the substrate.
In UV applications, three factors are of vital importance, according to Bob Sweetman, president of UVDoctors. Two deal with the UV lamps—power and heat management. A third is the ink and coating chemistry, particularly with hybrid ink technology.
“Power and heat management are competing factors,” Sweetman says. “In general, the higher the power level, the greater the need for more sophisticated heat management technology. Faster production speeds on the newer sheetfed presses dictate higher power levels,” he adds. “You need to balance power level with cost—cost increases as the maximum power level of the UV system increases.”
Avoid Drying Damage
Managing heat is critical, according to Sweetman, particularly to avoid heat damage to the sheets and to press components around the lamp. Long print runs result in heated press components, thus altering registration as the components expand. Similarly, elevated pile temperatures can negatively impact substrates. Water cooling and dichroic ‘cold mirror’ reflectors are two prominent heat management technologies.
UVDoctors’ latest offering is a water-cooled shuttered lamp system offering power levels of up to 600 watts per inch. Available reflectors include UV-enhanced aluminum and dichroic ‘cold mirror’ units. Lamps are controlled via an operator touch panel, and an optional mechanical chiller is available for water cooling.