23 July 2019 Digital Printing Technologies

IST keeps the faith in UV

IST can supply two styles of UV curing and is increasing competing with other styles of drying.

The problem with business forecasts is that as a business you are not always in charge of your own destiny.

Take LED UV. The technology is sound. It has been accepted and it brings undoubted benefits to printers and to their customers. Not to all printers, not even the most evangelical supplier would suggest that, but to a good proportion of commercial printers under pressure with short runs and faster turnaround times.

For many jobs there simply is not the time to have pallets of work in progress sitting on the factory floor waiting to dry. If the opposition is a digital printer without drying issues or an online printer able to accept orders until 5pm for delivery next day, a commercial printer simply needs to look at LED.

But that logic comes up against the hard facts of price, especially of ink. This has changed the dynamic in printing, explains Holger Khon, sales director and joint managing director of IST UV, possibly the largest supplier of UV technology to the printing industry. It offers the complete package for drying, it makes the lamps and subsystems, it produces the optics needed to focus the UV energy, it owns UK company ITL a development project business that has been LED since the diodes first appeared almost 20 years ago and it builds the full LED UV system that can be retrofitted to an existing press.

“The problem has been the reclassification of photo initiators that can be used the challenge that all the ink suppliers have in gaining access to raw materials and the difficulty of a regular supply. It has put the brakes on the technology a little,” he says. “The situation on the inks and coatings side does not help the ROI arguments.”

Fortunately IST is not dependent on the printing and packaging market. It is making inroads into industrial printing where merely printing wood effects is not enough: the job has to feel like wood which is where IST’s drying experience and coatings specialists combine.

And more importantly it has tapped into a market for sterilising water. Every ship travelling in open waters uses sea water as ballast. It will take this on in its home port and discharge it upon arrival. This has led to the unwanted spread of invasive species, damaging eco systems. UV can sterilise the water to stop this happening.

This is not an endless market, but is compensating for the bump in the printing industry. It is not doom and gloom in print: LED UV is still a growing market and now that the inks problems are settling down should again pick up pace. One that is already doing well is in mould labels, says Khon. “There is a big benefit with LED UV for this application because of the problems of handling this thin material on press.” The absence of heat in the UV energy created by the LED means there is no distortion in the films being printed.

The speed of take up in large format graphics printing suggests that the trend towards LED is gathering pace in that sector. Packaging too is looking hard at LED for flexible packaging, for corrugated and for cartons where the appeal is the sharp fall in energy required for a cure.

Carton presses tend to have a longer life than those for commercial print, so a printer has to think seven to ten years ahead rather than work in a three- to five-year horizon. By the time ten years are up, the market may well have switched completely. Hence the IST approach of using the same control and power units for both types of lamp. Should a printer wish to change all or some of the lamp systems to LED as power of these grows and the importance of energy saving increases, the printer has not locked the entire investment into a technology that has been bypassed.

“We know that chips with more power output are coming down the line and these are getting more efficient and have come down in price,” he explains.

This will help with inks issues as more powerful chips will allow ink producers to reduce the amount of photo initiator used or to switch to a compound that could not previously have been used. The argument for commercial printers adopting LED has not changed even if the challenges are greater than for a carton printer switching from one technology to another. “It is a step in a completely new direction for a commercial printer,” says Khon. “The LED unit is at the end of the press and delivers a fully cured sheet. They can print on different materials and can compete with digital printing.”

By Gareth Ward

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UV expands roles

UV expands roles

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