06. How anilox roll laser cleaning works
Laser cleaning itself is a well-established process. We have developed the process parameters and methods needed to remove ink safely from the roll’s microtextured surface. The ceramic layer applied to an anilox roll has high phase-transition temperatures: 2,435°C for melting and 4,000°C for vaporisation. Our process uses comparatively low laser power densities, heating the surface to temperatures far below these phase transitions and thereby ensuring safe cleaning.
Contamination is removed through a thermomechanical effect: a shock wave forms and breaks the bond between the organic or polymeric contamination and the anilox ceramic.
The process is highly effective because the laser beam, focused to a spot approximately 100 μm in diameter, heats the entire layer of contamination, removing the full volume of dried ink from the cell.
No other modern deep-cleaning method can reliably reach the bottom of a narrow, deep cell in a high-line-screen engraved roll:
- the cavitation process in an ultrasonic bath cannot be controlled, so there is no guarantee that the anilox roll’s original cell volume will be restored;
- when high-line-screen rolls are cleaned by media blasting, there is no guarantee that the particles will fracture into smaller pieces on impact and clean the cells to their full depth;
- both methods require a modest but continuous supply of consumables.