Comment
[Figure 2: Illustration of laser cleaning, showing ablation of dirt, while energy is refl ected from ceramic surface]
challenge is therefore not simply to restore volume, but to remove residues that alter surface behaviour.
Laser cleaning achieves this through laser ablation. A pulsed fibre laser delivers energy in nanosecond bursts at frequencies of around 20,000 pulses per second. These pulses are calibrated to affect contamination without damaging the ceramic surface.
When the beam strikes the anilox residues absorb the energy. They either heat rapidly and vaporise at around 500°C, or are lifted from the surface. The anilox remains unaffected, as it is capable of withstanding much higher temperatures, of around 2000°C. The laser wavelength is calibrated so that contaminants absorb energy while the ceramic reflects it. Because energy is delivered in pulses, heat transfer into the surface is minimal.
HOW THE SYSTEM WORKS IN PRACTICE In a direct beam system, the anilox rotates at speed while a laser beam is applied. The laser head moves steadily along the axis at a controlled rate, typically around 4cm per minute. This ensures consistent coverage across the surface.
With fewer moving parts, the system is mechanically simpler, easier to control and repeatable. Continuous motion also ensures even energy distribution, reducing the risk of localised over- or underexposure. A 40W laser source, with a lifetime of 30,000 hours, offers a practical balance between speed and long-term cost efficiency. A 1.2m anilox roll can usually be cleaned in around 30 minutes, while narrow-web rollers may take less than 10 minutes.
Energy consumption is relatively low - typically under 1000W during operation, comparable to a standard industrial appliance. Systems can be configured for both off- press and inline cleaning. Static units are suited to sleeves and easily removable rolls, while mobile systems are used for large or heavy rollers, such as in corrugated applications.
Operation is straightforward: load, select the programme and start. The process runs automatically, allowing operators to focus on other higher-value, problem solving tasks. Once complete, the anilox is ready for immediate use or storage. From cleaning to process stability The most important outcome of effective cleaning is not what can be seen, but what can be controlled. When surface condition is
fully restored – and provided other controls are in place - ink transfer becomes predictable, which in turn means stable colour density. Colour quality is thus predictable and repeatable, without the need for adjustments. From a sustainability perspective, anilox cleaning by laser ablation eliminates chemicals, the consumption of water and the disposal of wastewater. The process means less energy consumption. In fl exo, controlled processes are crucial for addressing the challenges of rising costs, shorter lead times, skills shortages and environmental impact. Processes that depend on ongoing adjustment and troubleshooting are not only ineffi cient, but less attractive to new talent. Stable, predictable workfl ows allow operators to focus on higher-value tasks, supporting both productivity and workforce development.
RETHINKING THE MEANING OF “CLEAN” A truly clean anilox, with restored surface energy as well as cell volume, provides predictable, repeatable ink transfer - forming the foundation of a controlled process. Consistency on press depends as much on the condition of the anilox as it does on the ink and the plate.
www.convertermag.com
July/August 2026
31
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38
