The modern newspaper printing process is a cold type, offset printing method used to produce high volumes of printed material at low cost. The printing cycle starts with a computerized desktop publishing version of the whole edition which is transferred, page for page, to a photographic etching station that produces aluminum positive plates of each page. These plates are inked and mounted on a specialized press in such a way that they transfer the image to a set of rubber rollers, which, in turn, transfers the image to the paper. The use of roller images transfer makes the process gentle on the paper and ensures high output quality. Most newspaper presses are large machines combining all of the steps of the printing, cutting, and assembly process into one unit.
Older newspaper printing techniques were based on dated hot type, or Linotype, processes. These were slow, costly, and labor intensive, which did nothing for the productivity of newspaper publishers, particularly during the 1970s where the demand for newspapers began to grow rapidly. During this period, the newspaper printing industry started a shift to the more efficient cold type processes which were quicker and cheaper. The average contemporary newspaper printing process is an evolutionary product of those early offset printing developments and is, almost exclusively, a cold type, photographic etching technique.
Most current newspaper printing process installations consist of large, complex single pass machines which often occupy several floors in a facility and can cost upwards of $40 million as of 2011. These machines print, cut, and assemble the entire newspaper in a single pass from continuous runs of newsprint, often producing up to 70,000 copies per hour. As newsprint is a fairly delicate paper, the machines and their internal processes are all geared towards gentle treatment of the paper during processing.
Typically, the newspaper printing process starts with the compiling of the entire edition on a desktop publishing computer program. From there, the completed edition is sent to the plate-making section, where each page is turned into a photographic positive on a thin aluminum plate. These plates are then mounted in the press and inked with rub-off resistant soy-based inks. Pages in black only require a single plate, while color photographs and print would need separate plates for the color elements. The mounted plates are positioned so that sets of rubber rollers pass across their surfaces during printing.
These rollers pick up the image from the plates and transfer it to the newsprint. This process is a lot gentler than pressing the plates against the paper, ensuring excellent output results. The facing pages are printed in sequence and pass to a different section of the machine that cuts and assembles the edition, completing the newspaper printing process. The complete newspapers are then batched and released for distribution.