Printing methods

By: Contigo Print Group
May 6, 2018

Contigo provides a complete range of services for printing and finishing, and through our suppliers we can complete all kinds of jobs, big and small – and with short delivery times. Most jobs can be handled by both small and large machines. The trick is to find the perfect match for each production, with the right quality and, not least, at the right price.

There are several different printing methods and we’d like to focus on them in this article. Here we’ll describe methods such as rotary printing, offset, digital and large format. The choice of printing method is also dependent on print size, paper type and format, as well as distribution and delivery time.

Rotary printing, heatset

For very large print runs

Rotary printing uses the same printing method as sheet-fed offset printing. With this printing method, a continuous roll of paper is printed on, which provides a much faster production time compared to individual sheet printing. Rotary printing involves a single complete workflow: first, the paper web is pressed through an oven, which dries the colours. Then additional drying occurs on cooling rollers and silicone is applied. This protects the print and leads directly to finishing in the folding tower for possible glue binding/stitching.

The printing machines produce several formats: A6, A5, A4 and A3 in different pagnations and in portrait, landscape as well as square formats such as 19.5 x 19.5, 21 x 21 or 30 x 30 cm. The paper range is more limited than sheet printing, and the grammage ranges from 45 to approximately 130 g/m2.

Rotary printing, coldset:

Not just newspapers

In contrast to heatset printing, ink drying occurs through absorption into the paper, which differs from evaporation with air and heat. It is most common to print on paper grades that are uncoated, but we can also supply hybrid printing where the two printing methods are combined in one and the same printing cycle. This means, for example, that a print job can have its very own graphic expression by simply using two different paper qualities, thus sending a unique and different signal to readers. The machines are 3 wide with 6 up plates, which allows for other formats.

Contigo has access to a production capacity of up to 320,000 items of print media per hour. If two print tray towers are connected together, 2 x 96 tabloid pages can be produced in one printing.


CMYK colours, Pantone colours and assorted varnishes: many options

Heatset is most often the cheapest solution for large print runs – even if start-up costs are greater than for gravure and digital printing.

Our sheet printing presses are also based on Heidelberg machines with automatic colour management and a production of up to 18,000 sheets per hour. Quality is checked on every sixth printed sheet, and a preflight programme ensures that low resolution images are discovered in time. If trimming marks are missing or colours are used that are not on the scale, the warning lights also go off.

Contigo’s suppliers all have certified management tools that optimise production and ensure a competitive price level. Please note that offset printing is cheaper than digital printing with approx. runs of over 1,000 copies.

Digital printing:

All run sizes with short deadlines

Print-on-demand: Digital printing, without film and printing plates. The process occurs directly from the computer to the printing machine, which limits start-up costs. Digital printing is suitable for fast delivery of in-store material in connection with projects such as an impulse advertisement campaign for the retail trade. Similarly, a new packaging design can also be tested as it’s easy to change graphic tools and motifs – and at reasonable prices.

Several of our regular partners print using HP Indigo presses. This is very close to genuine offset printing, in part because the rubber plate and back pressure cylinder have the same effect as on a traditional offset printing machine. Another option is the use of Linoprint from Heidelberg, which is an advantageous solution due to its speed and minimum production of waste paper. It prints in formats of up to 700 x 300 millimetres and in 4 CMYK colours as well as other colours.