Direct to plate printing is a fairly new technology that eliminates the use of film in printing. Traditional methods of printing, called offset lithography printing, produced film on an imagesetters and used it to make a metal printing plate. The plate then went on a printing press to make the printed impressions. With direct to plate printing, the printing plate is produced directly from a computers, eliminating the need for film.
Although direct to plate printing is a new technology, it is becoming very popular due to its cost-effectiveness. Production of film costs a great deal of time and money, and direct to plate has cut out the middleman in order to save on both. Direct to plate printing is also environmentally friendly and has a higher productivity rate.
Without the use of film in the printmaking process, the technology has had to evolve and expand to maintain the quality of the prints. Some print manufacturers have brought out their own development techniques to make sure there is no loss of quality with the elimination of film. Kodak has developed the Direct Thermal Printing Plate, which uses thermal imaging techniques as opposed to the silver halide or photopolymer technologies used by others.
Direct to plate using thermal imaging involves applying focused heat from a laser diode to the surface coating on the plate until a threshold temperature is achieved. When this happens, an image is formed as written by the platesetter. If more heat is added, nothing happens; the image will not change. It will match the platesetter image exactly, with no dot gain. Many tiny dots make up a picture. Using film has produced plates with some gain in dot tone that need to be checked against the negatives before printing.
Both film and plate processing involve harmful chemical substances. Although direct to plate printing does not eliminate all the harmful substances, it does produce less than traditional film processing. Another benefit of direct to plate is that, because the film is eliminated and the work is produced via computer, manufacturers save on processing and there is less work involved in the film stripping and proofing.
The proofing of prints brings us to a potential problem with direct to plate printing. Proofing of prints is vital at most stages of the printing process. Proofing film can bring attention to errors that can be corrected, but with direct to plate, there is no way to accurately judge the image that will be printed. This is a flaw in the technology; some loss in quality may be a trade-off of the many benefits of direct to plate printing. While the technology is being developed, it may be up to the customer to decide if the quality of the prints is to the standard they desire.