NCR stands for No Carbon Required and is the modern day replacement for the old-fashioned carbon sheets that were used to transfer impressions from sheet to sheet.
Today, the sheets of paper used to create an NCR form are coated with dye capsules and/or a layer of reactive clay. The back side of the topmost sheet is coated with a layer of microscopic dye capsules. These tiny capsules break open when pressure is applied by a writing instrument or the mechanical strike of a printer.
The dye then spills onto the top of the second sheet, which has been coated with a reactive clay compound. This thin clay layer chemically reacts with the spilled dye to form a permanent mark. Because the dye capsules are microscopic, the spilled dye does not spread excessively and results in a very precise transfer of the original text.
The origins and history of NCR paper can be found HERE for my fellow paper nerds.
The difference between offset printing and digital printing is the way in which the images get transferred onto the paper. It is this difference that affects the cost economics of running these machines – and ultimately affects the prices paid by you, the customer. The real-time price calculators on our site have been meticulously formatted to interpret your requested print specifications, then automatically determine which press type can produce the job most cost efficiently.
Offset printing uses etched metal plates that apply ink onto a sheet of paper. The setup for offset printing is generally significantly more time consuming and expensive than digital printing. The metal plates – one plate for each colour being used – need to be etched, and applied to the rollers that transfer the ink onto the paper. While the setup takes time, the actual printing process runs faster than digital – meaning large quantity runs of the same form makes sense – especially when limited ink colours (1 or 2) are used.
Digital printing uses electrostatic rollers called drums to apply toner onto the paper. The drums (one per each colour being printed) use an electrostatic charge that attracts toner in the form of toner density. The toner is then applied onto the sheet and fused – via a heat unit – onto the paper. There is minimal setup involved, meaning that small jobs can get on and off the press quickly with minimal changeover time. The inks drums require little attention, meaning lots of colours (including full spectrum CMYK) can be printed cost efficiently.