In offset printing, platesetting methods have always relied heavily on the use of chemicals. Although the technique has continually improved and the number of chemicals needed has decreased, it was never possible to completely remove chemicals, water, electricity or film from the process. In this article, we reveal what has changed.
The production of print plates poses a major challenge for many printing houses, which they must face every day. The demands of high print quality, small print runs, multi-shift production work and speedy offset presses have continuously increased the demand for printing plates. Combined with this, many companies are also interested in non-stop, automated production process and environmentally friendly or climate-neutral production. As a result, the demand for process-free printing plates increased significantly – also here at SAXOPRINT. Owing to our enthusiasm for innovation and efforts by printing plate manufacturers, we started a project to introduce chemical-free printing plates at SAXOPRINT in 2018.
How process-free platesetting works
Member of staff at the control terminal of our platesetter unit
With these plates, known on the market as “process-free plates” or ablation plates, the print image (made up of many tiny dots) is hardened on to the plate coating. These areas of the negative plate then absorb the ink in the printing process and transfer it to the paper via the blanket cylinder. Print-free layers no longer need to be washed out and cleaned in a developing bath but are now removed in the press by the pull of the ink. Even during the press set-up phase, the first 10 sheets are cleaned. The advantages here include less waste and the avoidance of negative influences on good sheet production.
Close-up of a process-free printing plate
he layer underneath absorbs water and thus cannot absorb ink. This is how conventional offset printing works. Just like when cooking at home, oil (which is in ink) and water repel each other. Consequently, you have printing and non-printing areas for each colour tone. The standard colour mixture of 4 basic colours can produce any colour, depending on the combination of the individual colours.
To make the most of the process-printing plate, it was necessary to minimise the drawbacks. Important factors, such as printing waste, were not allowed to increase. Water levels had to remain stable for the printing process. New filter systems were also developed that even saved the need for expensive disposable filters.
Resource savings with process-free platesetting
We save …
5,500 m³ of water
40,000 litres of chemicals and chemical waster
13,000 litres of rubber coating
9,000 kWh electricity
1,000 hours of maintenance and servicing
(Average values calculated for the entire year)
SAXOPRINT confirms drive for innovation
The employees were provided with new T-shirts as part of this initiative and play a key role in supporting the new operating process.
We have overcome several obstacles, so that since September 2019 SAXOPRINT has been working entirely with process-free plate technology. Overall, this marks the conclusion of a superb project. And not only have processes been optimised, but valuable work has also been done in terms of environmental protection.
Among others, we use the Heidelberg Suprasetter 145/162/190, a large-format platesetter with a patented laser system for highest precision and reliability. In terms of plate volume (1.2 million m²), we are by far the biggest customer worldwide with the new process-free plate, making us absolute pioneers. We are proud of this and have shown the market how sustainable printing in the field of plate imaging is possible today.