OFFSET PRINTING

Offset printing: everything you need to know

Offset printing is a printing process that enables you to print a wide range of high-quality materials at low cost.
Unlike digital printing, which starts with a single copy, offset printing requires a number of physical and technical interactions.
The flexibility of offset printing means that we can print almost any type of paper in any quantity: brochures, cards, leaflets, folders, booklets, envelopes, letterheads, etc. Printing processes : Ink is applied to the substrate via an inking unit.
The film of ink emerging from the ink fountain is stretched over several rollers, which are then brought into contact with the form on the zones of the offset plate.
There are two offset printing processes: wet offset and dry offset. The wet offset printing principle (conventional) is based on the fact that water and grease are immiscible.
The aluminum offset plate serves as a support for a hydrophilic layer (salt) and a lipophilic layer (copper or polymer).
To create the printing form, we engrave the offset plate with a laser to remove part of the layer.
The result is a partially removed hydrophilic and lipophilic layer.
Four-color printing is used when the press is composed of four printing units.
Six printing units are referred to as hexachrome offset printing.
In the case of Pantone® printing or the application of a varnish, we speak of direct-tone offset printing. In water less offset printing, the unprinted areas are coated with silicone.
This process is much faster, and paper loss is much lower.
The result is a high-quality, stable print with better contrast.
As mentioned at the outset, the various costs involved in offset printing (plates, inks, etc.) make it too expensive for small runs.
In this case, we’ll switch to digital printing. Machine type: Sheet-fed printing is the most common for larger or smaller print runs.
The press is fed with sheets of various formats (depending on the press model).
Rotary press printing is used for high-volume, high-speed printing, and is fed by paper reels.