I’ve heard the term offset printing, but I’m not sure exactly what that means, or why it is important. Can you help?
The most important thing to know about offset printing is that it is most appropriate for larger runs of printed material, (e.g., quantities of 500 and up, per design). Far from being extinct, over 90% of printed material worldwide is printed offset. However, the process of printing offset is involved and time-consuming, thus most of the cost is in the set-up. If you are doing smaller quantities (e.g., under 500 per design), usually digital printing is more economical.
“Offset” in printing terms refers to the process of printing by creating plates and then having the plates offset to the rubber blanket, which then applies the ink to the paper. Plates are typically metal or polyester, though they can be made of paper or plastic. At our print shop, after we have a signed off proof, a DPM (digital plate maker) is used to create a plate for each color used in the printing. For instance, if it is a business card with two colors on the front and one on the back, we would have to make three plates to run the job correctly. We would also refer to this as being “three passes” through the machine—because that is how many times the paper must go through to imprint all the colors correctly.
There are also four-color presses, which use the CMYK process (e.g. one plate each for cyan, magenta, yellow and black separation) to print in one pass. With every trip through the machine there is more chance for error if everything doesn’t line up.
What interests you most about printing? Would you like more information on offset printing, or another print topic? Was this blog helpful to you, or could I be more clear in my explanations? Let me know in the comments.