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XPS Crystal : Improve consistency with patented UV LED exposure

The innovative XPS Crystal optimally combines main and back UV exposure.
Unlike UV exposure tables that use luminous lamps with fluctuating intensity, the XPS Crystal uses UV LEDs that do not require preheating and always emit consistent radiation.The optimally controlled, synchronized main and backside UV exposure produces highly consistent digital flexo plates for every type of digital flexo plate, and at any time of your production day.The XPS Crystal exposure equipment achieved the prestigious FTA, 2017 Intertech Technology Award and Red Dot awards.

Reference Information
Conventional exposure tables use fluorescent lamps to produce the ultraviolet light with which photopolymer flexo printing plates are exposed. In order to increase processing speed and efficiency, new systems have emerged in recent years that propose the use of high-intensity lamps, on the basis that transferring more energy to the plate, with less time on the exposure table, would result in higher productivity and plate consistency.
Esko launched its XPS Crystal exposure unit in 2016, promoting a new method of plate exposure: using a narrow formation of light-emitting diodes (LEDs) to produce high-intensity UV light, the opposite concept of exposing the entire plate at once.
In the Esko XPS Crystal model, the LED array travels over the plate surface at a constant speed. This avoids the need for preheating time and eliminates the risk of spot cupping due to inconsistent exposure or overexposure of the plate.
LED structures do not degrade like fluorescent lamps, which typically lose 30% of their radiation over 1,000 hours of use, requiring lamp replacement and unstable plate production.
A typical LED group does not degrade over time and has an estimated lifetime of more than 5,000 hours, allowing perfectly controlled plate production.
LED light is cool, which minimizes heat distribution on the plate, as well as generating uniformly shaped spots across the plate. This is in contrast to fluorescent lamps, where the quality of light emission varies from lamp to lamp.

Test Regime
To explore the relative advantages of the unit with its exposure technology, Esko conducted a series of comparative tests with conventional exposure (CE) and conventional cold exposure (CCE) tables to compare and contrast performance with the Esko XPS Crystal.
If the Esko XPS Crystal unit provided a more consistent exposure method, it demonstrated less measurable variation compared to the caliper on the basis and size of the dots created across the tonal range.
To ensure consistency of analysis, preliminary tests were performed to:
- Identify the correct processing time for each exposure device.
- Verify the correct minimum spot value for each exposure type
- The remaining ambient temperature of each exposure table was confirmed to establish the temperature point for conventional cold exposures.