After installing Tresu’s FlexiPrint IMW E-Line sealed chamber doctor blade system Austrian converter, Constantia Patz, has reduced maintenance time and consumable costs.

The Loipersbach-based company has installed the system onto two of its inline flexo printing presses.

The plant, which produces aluminium foil for blister packs, sachets and container seals, installed the system on all stations of the nine colour and eight colour 800 mm wide BHS presses during two retrofitting operations.

The new doctor blade systems eliminate the problem of leakage that occurred on the original chambers, which were installed when the presses were built 14 and 17 years ago respectively.

The FlexiPrint IMW E-Line features rubber seals that form an airtight closure, preventing ink and solvent fumes escaping. Thanks to precise positioning, the doctor blades offer longer working life, and, with the ‘E-Line’ clamp system, fast blade-changeover.

Wolfgang Elian, head of printing department at Constantia Patz, commented, ‘We are achieving blade production lifespans of 24 production hours – three times longer than those used by the original system. We are exchanging blades in just two minutes, compared with 15 minutes needed to replace each of the previous system’s screw-fastened blades. Because we have 17 printing stations in total, this quick exchange substantially reduces downtime and enables our operators to focus on higher-value quality control processes in a cleaner, solvent-free environment.’

Additionally, the closure created by the chamber and the blades prevents contamination of the ink with the atmosphere, allowing long-term storage of leftover ink.  ‘We are able to interrupt production of a job over the weekend, for example, and continue at the beginning of the next week, without needing to drain and refill the chambers. And we can do this with the reassurance of high quality print results,’ added Mr Elian.

According to the company the precise positioning of the doctor blade and the constant pressure within the closed chamber eliminates foaming. This ensures a direct, controlled transfer of the ink and coating agent to the anilox roll cells without bubbles. This results in a uniform printed layer that dries more efficiently, with higher reflective and gloss values on paper and film. The chamber system ensures controlled ink flow when the BHS presses reach their top speeds of 200 m/min.