Offset printing

Among the available printing technologies, there is no other that can compare with sheetfed offset printing in terms of flexibility with regard to: the printing materials used, the print run size, the finishing possibilities or the range of products that can be produced with it.

What is offset printing?

Offset printing is referred to in technical terminology as intermediate printing. This is primarily due to the specifications of this printing method. This is because the graphic design is transferred onto printing plates covered with photosensitive emulsion on an aluminium substrate. The moulds are prepared using CtP (Computer to Plate) technology. The finished moulds are mounted (fixed) on mould cylinders. In contact with the ink and water rollers, an ink layer with a wetting solution is applied to the printing elements of the mould. This image is then transferred from the mould cylinder via physical contact to an intermediate cylinder covered with a rubber jacket. From the intermediate cylinder, the image is transferred directly to the printing (impression) cylinder underneath and to the printed sheet of paper currently on the surface of this cylinder. This is the operating diagram of a single printing unit (so-called printing unit). Between the printing units, the sheets are transferred by means of transfer cylinders (so-called transferters) with the use of special feet on their edges, which transfer the sheets to each other in a very precise (relay-like) manner.

Four process colours are required to print a full-colour image on a sheet: Cyan – the colour blue (C), Magenta – the colour purple (M), Yellow – the colour yellow (Y), Black – the colour black (K), in short: CMYK. For each process colour, one print mould is required, installed on individual print units.

What are the advantages of offset printing?

When deciding to produce promotional materials with the help of offset printing, many customers recognise the benefits right from the start. The biggest advantages of this technology include:

• Wide range of colour reproduction available – offset printing capabilities also allow the use of special colours (Pantone-compatible, HKS) tailored to customers’ needs.
• Precise reproduction of details – suitably equipped machines have the ability to automatically watch over the printing process and ensure that it is correct;
• High quality – offset printing guarantees that the materials prepared will be of the highest possible quality and will not disappoint customers’ expectations;
• Durability and colour intensity – offset printing is also distinguished by its exceptional durability and colour intensity. As a result, they will effectively attract the eye and focus attention;
• Flexibility in the choice of paper substrate – customary from 60 g/m² to 350 g/m², but substrates with considerably higher grammages are possible – e.g. cardboard, solid board. No other printing technique offers such a high degree of flexibility in the choice of substrate, while still being able to print in high volumes;
• Flexibility in the choice of finishing: foiling, varnishing, embossing, gilding. etc. Other analogue printing techniques do not allow such a free choice of finishing methods.

So as you can see, offset printing offers unlimited possibilities to personalise your designs and customise them.

How long does it take to prepare materials by offset printing?

Thanks to the possibility of accepting files for printing on line (via a browser using Kodak InSite Prepress Portal software), and the automated process of preparing printing forms – nowadays, the prepress process has been significantly improved and shortened. The Kodak InSite system gives our customers a convenient possibility to check the correctness of production files, imposition of work, and remote acceptance of the order by the customer online, without getting up from the computer and leaving the office.

Technical aspects of printing in our print shop

We print using offset printing technology on eight-, five-, and two-colour machines. Our machinery enables very fast double-sided full-colour printing up to B1 format, as well as single-sided printing in the case of works with dispersion varnish or the need to use inks in special colours (Pantone and HKS) beyond the standard CMYK space.

State-of-the-art offset printing machines from reputable manufacturers ensure the highest available print quality and efficiency, for which we are known in the market. These machines have spectrophotometric colour measurement, with the ability to measure each print in real time, thus guaranteeing that the expected effect is maintained throughout the print run.

We use the CIP3 system, which allows us to transfer information about the initial setting of the ink profiles from the CtP studio directly to the printing machine, store this information and use it for renewals, in order to maintain the colour repeatability of subsequent editions.

What are the other types of offset printing?

Other offset printing techniques include web offset: coldset and heatset, where the ink is fixed in a continuous printing process on a web of paper pulled through successive printing units – respectively “cold” or “hot” using a drying oven.
The choice of the appropriate printing type depends on the form of the print products to be prepared. Cold-set is the technique most often used for newspaper printing. Heat-set is a technique that is successfully used for publications with very large print runs, however due to its specific characteristics it is not used for medium and low print runs. In addition, the price for the available high efficiency is the limited selection of available printing materials (max. grammage 115 g/m2 ) and the lack of post-printing finishing options.