DG press ServiceS is specialized in building web offset printing presses; however, most of our presses are equipped with a hybrid printing configuration. This means that the press is equipped with at least 2 different printing techniques in line. The three most common ways of printing are rotary, semi-rotary and sheet-fed printing. As mentioned above; DG press focusses on rotary (web) presses.
Let’s focus on offset printing (also called lithography). This is one of the most common ways of creating printed materials. A few of its common applications include: newspapers, magazines, brochures, stationery and books. But offset can also be utilized for other applications such as business forms, security printing and flexible packaging.
Compared to other printing methods, offset printing is best suited for economically producing large to medium volumes of high quality prints in a manner that requires little maintenance. To complete the comparison; flexo is most suitable for printing shorter jobs, and gravure printing is most suitable for printing very large jobs with the same image. Economically; offset is positioned between flexo and gravure. This is due to higher set-up costs compared to flexo printing, and lower set-up costs compared to gravure printing. More about set-up costs and the pre-press process can be read in the pre-press section of our website.
An offset printing unit always contains a water pan with water rollers to apply water to the plate cylinder. And obviously it also always contains a ink tray with ink rollers to apply the ink to the plate cylinder. Ink and water are applied to the image carrier, which transfers the image to the offset cylinder. The offset cylinder is mainly made out of rubber which allows for easy transfer of the image to the substrate. To ensure that the ink is transferred correctly, an impression cylinder makes sure that the substrate is pressed against the offset cylinder. This process happens for each individual color to eventually get to a full color image. The most basic image consists of 4 colors; CMYK, Cyan, Magenta, Yellow and Key (black).