Offset Printing

For Long Print Runs, Offset Printing Offers the Most Cost Effective Option for High Quality Printing

Offset printing has long been the workhorse of the printing industry producing high quality and high volume print runs. In this process a metal plate is created that holds the text and images to be printed.  In order to produce “full color” or “4 color” printing, four different plates must be made, one for each of the four primary colors of cyan, magenta, yellow and black (sometimes called CMYK). Once these plates have been mounted on the press they are moistened (or dampened) with water.  Since water and oil don’t mix the non printing areas of the plate will hold the water and the ink, which has an oil base, will not stick to it.  The other areas of the plate that contain the text and images that are to print are not moistened which causes the ink sticks to it.  As the cylinder holding the plates rotates it comes in contact with a rubber coated cylinder and the ink is transferred from the plate to the rubber.  Then that cylinder comes in contact with a third cylinder that presses the paper against the ink and “offsets” it onto the paper.

Most offset presses also have the ability to add an aqueous coating to give a polished look to the finished sheet. The downside to offset printing is that the metal plates required for the press can be very costly and time consuming to mount on the press.  This upfront cost makes offset printing uneconomical for short press runs. Conversely on very large print runs offset printing becomes the most economical since the plate costs are amortized over a high volume of press sheets.  If you are having a hard time deciding whether offset or digital printing is best for your project check out our explanation of the differences between the two types of printing by clicking on the “Offset versus Digital” quick link to the left.