Flint Group announces Catena + automated flexo platemaking system
When the Xeikon pre-press team designed a brand new imager for 50x80-inches digital flexo plates, they went to plate manufacturers and high-volume plate makers to first discover any difficulties that they faced. It was obvious that a major challenge was simply handling such large, malleable, vulnerable and heavy plate efficiently. Thus, the ThermoFlexX 80 was born.
27 Aug 2020 | 2558 Views | By Rahul Kumar
The electronics, mechanics and optics were totally re-designed but the feature that caught the industry’s eye most strongly, was the ‘FlexTray’. This is a ‘trolley’ that can be used to fetch, load, unload and take a plate onto the next process step but forms an integral part of the imager for operation. FlexTray proved to be of real assistance for operators handling large flexo plates, needing only one operator and minimising the risk of damage. ThermoFlexX imagers had arrived and marked the beginning of a new era of automation in flexo plate imaging.
Xeikon became part of the Flint Group in 2015. There was an obvious and immediate synergy between the Xeikon Pre-press (ThermoFlexX) and Flexographic teams. Xeikon pre-press had innovative design engineers and a wealth of experience in plate imaging with automation, flexographic brought in-depth experience of plate chemistry and application. The imagers benefitted from joint developments such as ‘woodpecker’ surface micro structures for better ink-laydown giving higher quality flexo print.
ThermoFlexX systems are built in a large factory in Ypres, Belgium with a highly skilled work-force and capacity to make more (and larger) products. Developments naturally progressed and now, under the ThermoFlexX brand, Catena, a full range of plate processing equipment has evolved.
To suit most needs and budgets, Catena is a modular system. The units consist of Catena-E UVA LED exposure, Catena-W a plate processor (wash-out) and Catena-DL dryer and light finisher or Catena-DLS dryer, light-finisher and plate storage (stacker) system. A description of each unit follows along with integration and remote support possibilities.
Catena-E is a high performance exposure frame utilising latest technology UVA (365-nm wave-length) LEDs for both main and back exposures. Plates up to 7-mm gauge are supported. Main exposure is performed by 24 specially designed LED modules traversing above the plate. Back exposure is simultaneous using a full coverage LED arrangement for greater control and faster processing speeds. An automatically operated lid protects the plate from environmental issues (dust) during operation. Water cooling with air-conditioning and channeling maintain a fully stable environment inside for absolutely consistent exposures. The placement of LEDs gives a high concentration of intensity at the plate surface. Oxygen effects are eliminated hence Catena-E produces Flat-Top-Dot output for a perfect combination with, for example, Flint nyloflex plates and Woodpecker Nano fine surface micro structures. Catena-E offers secure but open operation with users able to adjust their own parameters to optimise exposures to their own requirements.
Catena-W is an incremental flexo processor or wash-out unit for solvent chemistry plates. The 3200-mm of wash-out length consists of rotating and oscillating brushes. A separate section at the input removes and contains the LAMs layer. Additional brushes behind the plate at the end of its travel remove residue from the back to avoid the need for a separate clean-up operation. Plates are loaded without the need for pre-punching. Sensors check that the plate is aligned for input and then an automatic grip/punch attaches a pin-bar to pull the plate through the wash process. In turn the pin-bar is propelled by a leadscrew system that sits in its own enclosure, free from solvent. There are 3 pin-bars and these are transported back to the loading area automatically. Once they are through the wash-out process, plates rest on a trap-door. A shuttle (trolley) system is provided to transport plates to the dryer without an operator needing to touch these solvent-wet plates. The trap door only releases the plate when sensors confirm that the shuttle is in the correct position. This extra ‘rest’ position means that the gap in the queue between plates can safely be reduced to a minimum distance of 50-cm giving extra productivity. Catena-W solvent sections are very well sealed and ventilated by built-in extractor motors. This ensures an absolute minimum level of solvent odour in the plate-room adding to a more pleasant working environment.
Catena-DL is a plate dryer and light-finishing unit. It has six dryer sections with independent heaters and temperature control. Unnecessary sections needn’t be active if they aren’t required, saving energy costs. The light-finisher section has both UVA and UVC tubes. These are monitored by sensors moving into a range of positions between every operation to measure and record light intensity. The operator is notified if lamp power is outside of set specifications.
Carrier trays are supplied for each dryer section. In combination with the lifting arms on the front of the unit, each plate can easily be handled and manoeuvred into any section or the light-finisher with ease.
Catena-DLS is a plate dryer, light-finisher and storage (stacker) unit. This can be added to a Catena-W (making a WDLS). The dryer has 10 sections with the same attributes as the DL (above), a light-finisher with monitored UVA/UVC and robotised plate moving and stacking between 7 storage positions. This manoeuvres the plate through drying and light-finishing. As well as storage positions for finished plates, the stacker can act as a ‘rest’ position to ensure that plates are properly cooled after drying before being light-finished.
Further automation is provided by linking a ThermoFlexX imager to the Catena-E exposure unit via a Catena-B bridge or ‘rover’ system. This takes imaged plates automatically from the imager through main and back exposure. A Catena-R rotator unit can take the plate from exposure directly into the wash-out unit. This full-inline system is referred to as Catena+, the only fully in-line plate making unit actually available today. It is likely to be unique in the market for the considerable future as the only full in-line system available from a single manufacturer. It has long been a Utopia objective for high-volume operations to have completely hands-free plate making from imaging through to the finished plate. Such levels of automation provide the highest productivity, lowest waste (from miss-handling) and the opportunity for extra plates made with no operators present, for example overnight or end-of-shift.