Digital Plate Primer : Enviro Plate ConsiderationsNovember 2010 By John Zarwan
(Editor’s Note: This article is a condensed version of the 2009 report by J Zarwan Partners titled “The Environmental Impact of a Printing Plate.” A revised report, including the new Kodak Trillian SP thermal plate, will be published later this year.)
Printers around the world increasingly are paying attention to reducing the environmental impact of their operations. Owners want to be good citizens. Governments are focusing more on environmental compliance and the reduction of emissions and waste. Customers are demanding “green” policies and procedures.
Even aside from these societal pressures, there are still very good reasons for printers to focus on improving operations and reducing waste. Simply put, waste of any type does not add value. Reducing it means increasing efficiency, shortening turnaround time and lowering costs.
One process that has received a great deal of attention—and that all printers can focus on—is that of plates and plate making. All major plate suppliers have made great strides in reducing the amount of chemistry and waste required to process offset lithographic printing plates.
That said, a number of claims are being made, and there is a great deal of confusing information. This report is an attempt to bring some clarity to the issue. While environmental considerations are only one factor in the choice of a plate, it is important to be aware of the differences and the amount of chemistry and other waste involved.
Sources of Waste
Processing of plates consumes three primary resources: chemistry to develop or process the plates; energy to run the processing unit; and water to rinse the plate, dilute the chemistry or clean the unit. Similarly, processing generates waste, which must be disposed of, in the form of spent chemistry, waste water and containers. Some plates, such as silver-based violet plates, also require a silver recovery system. Each plate type and process consumes different amounts of these resources, depending on the imaging laser, emulsions used, and chemical and physical reactions required to develop or wash-up the plate.
In addition to the direct resources used in the processing of plates, there are indirect resources used. Plates and processors must be manufactured and delivered, all of which require materials, energy and water. Each of these also has a carbon footprint.
There are a number of different technologies available for digitally imaged plates: