The company says that while thermal chemistry free plate technologies are already available from major suppliers, they are not as popular as violet for the newspaper industry.

Approximately two thirds of newspaper CTP installations have been with violet platesetters, which combine the violet benefits – unbeatable speed, unbeatable laser reliability low cost of ownership, excellent image quality and so on and will continue to be used for this reason, Tony King, of Agfa says.

"The reliability (life time) of the violet diode is significantly higher than the reliability of thermal diodes – which is why some suppliers are offering violet laser warranty over the lifetime of the platesetter.

"For newspapers, the reliability requirements are paramount, with everything dependent on the need to produce the plates quickly in the short time available before the press starts.

"Although thermal CTP has its benefits, these are of less value for newspapers. It is a simple fact that three of the key benefits of violet are that Violet diodes are inherently more reliable than thermal diodes; Violet plates are naturally more sensitive than thermal plates, and violet platesetters remain the best choice for high speed platemaking and Violet technology intrinsically carries a lower cost of operation for the total system; daily production, maintenance, and reliability included."

He says chemistry-free plates have already been widely accepted as one of the most important recent innovations to simplify platemaking in commercial printers because elimination of the developer means that one of the main variables affecting image consistency disappears.

Cleaning out the processor and disposing of exhausted developer is no longer required and the expensive plate processor itself is no longer needed.

"All these benefits are important to the newspaper printers who are looking to streamline, simplify and reduce costs. At the same time chemistry-free increases the green credentials of any newspaper keen to minimise their environmental impact."

He says smaller newspapers with shorter run lengths and less demanding plate productivity requirements will initially be the most likely to become early adopters of the new technology but time will tell if the first violet chemistry-free plates have run length restrictions that may limit the initial applications, for example.

"Image quality, however,  will be just as good as existing newspaper CTP plates. Assuming that run length, productivity and other performance requirements are met then there should be no restrictions to the use of violet chemistry free plates."

Violet chemistry-free plates work by being coated on high quality grained and anodised aluminium. The coating is sensitised to Violet (405nm) light.

During exposure, the violet diode hardens the image area. The non image area remains un-exposed.

The exposed plate is gummed with industry standard plate gum. During this process the soft, unexposed non-image area is easily and cleanly removed by the gum.

The finished plate looks, feels and prints like a normal plate. The plate isn’t sensitive to light, and can be stored prior to press if needed.
Kings adds that chemistry-free plate technology is likely to have the same significant impact in newspaper CTP as it did in commercial CTP.

"We believe that 2007 and 2008 will be important years in the roll-out of violet chemistry-free newspaper plate technology. Chemistry-free may not be for all newspapers, but it will make a significant breakthrough for many and will be almost as important as the original introduction of newspaper CTP technology back in the 1990s."

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