The colour separation for multichrome printing up to 12 colours for screen and flexo printing applications gives an enormous added value to print advertising, visual communication and packaging.

In the world of packaging and visual communication, whether external or indoor, images requires more and more : colours must be faithful but attractive too and especially deep, almost three-dimensional. A normal four-color printing can be “flat” and lifeless when compared with the same print separated at up to 12 colours and printed with the appropriate screens.

It could seem to be no more space for true innovative solutions, as for colour separations since four-color printing (CMYK) is firmly established.But we discovered a revolutionary software for multichromatic separation (up to 12 colours) specific for flexo and screen printing, as well as digital. We therefore considered it appropriate to deepen this item to give the readers a new working tool that could open up new opportunities, in particular for textile designers.
We turn to an expert, Gianpaolo Coin, CEO of Grafco, an Italian company specialized in the production of inks for screen printing and digital machines, who has followed the development and implementation of XerioSEP a revolutionary software for color separation and his RIP, as we are sure that prepress and visual communication operators will reap considerable benefits in their work.

MPA – Today for who is involved in the prepress industry the colour separation is normally intended the four-colour (CMYK) a firmly established technique. Why did you decided to develop a new specific separation software?
COIN – It is true that the four-colour separation has been developed since the early 1900s for multi colour imaging, using the minimum number of inks, 4 in fact or, better, 3 plus black.
The packaging market and today’s advertising requires more and more high-impact images and in this respect the creative and communication managers are constantly looking to obtain an extended and powerful presence with colour images that capture the attention and seduce eye of the beholder. In short, they try to get a “fine print” that catches attention.

MPA – But the colour separation in the field of flexo and screen printing is not limited by the demands of the customer who always aims to keep costs down?
COIN – In fact we have noticed that in many productions in addition to the four-color shades it is usual to introduce in the printing of Pantone tones also called spot colors sequence largely to reproduce correctly the colors of the logo of the brand in question.
Today, companies that operate with a focus on quality tend to work in polychrome and then to N colors to achieve a result that has a high visual impact and is able to catch the eye at first glance.

MPA – Really the brand owners demand more colours. But how does your software automatically generates a separation ready to print?
COIN – Our software generates a separation of up to 12 colors of the original image spots in an extremely simple and safe. The software works with powerful algorithms ‘color mapping’ so the file, when separated from a chromatic point of view, both as a whole as faithful as possible to the original image colors.

Competences and creativity

MPA – A special knowledge is required for this?
COIN – Our staff prepares prepress operators to correctly use XerioSEP, interpretation and proper use of such separations; then, when they acquired a good experience, we leave themselves full freedom to use XerioSEP to get the best possible result according to their sensitivity and creativity, and according to the images to be processed.

MPA – This separation in more colours of XerioSEP is usable for any kind of image?
COIN – Actually, especially in packaging printing, each image has a colour palette and a different colour complexity; that’s why we consider it very important to teach, with a special workshop to the specialists interested in our system, to make best use of separations generated by XerioSEP. Who knows how to use XerioSEP considers this an invaluable tool to get in a few minutes separations for textile prints of high quality and eye impact.

Quality and cost saving

MPA – But, it may be enough to use Photoshop or something similar ? There are various product on internet …
COIN – We know that on internet are advertised colour separation systems and plug-ins for Photoshop that promise miracles. But, as determined by our own customers who are using XerioSEP after years of experimentation and trials with this APPs downloaded from internet, the results obtained with our system is in no way comparable with those proposals.

MPA – Who decides in the production process how many colours should be separated to be allocated to the flexo or screen printing ?
COIN – XerioSEP is used to adjust the separation of the number of colours to the kind of printing machines available for production. It is obvious that if a company has flexo machines 8-10 colors will not use a separation in 12 colours. Similarly for a 8 colours screen printing carousel.

MPA – Anyway to get the colour of a brand typically must use a particular Pantone. You can get around this?
COIN – Normally, the flexo industry tends to use the n-colour + spot colour usually linked to the brand logos to be printed. XerioSEP instead allows to also decide ‘a priori’ the number of colours to utilize with the same result, and thus reduce costs, why and in this case XerioSEP allows to reduce the number of colors of the separation to the minimum necessary to obtain a qualitatively valid result and approved by the brand.
MPA – In your opinion what types of images, and in what applications, the color separation polychrome done with your software has brought the biggest change from the traditional separation in full colour?

COIN – Very interesting question … Our software has been around for ten years and we have seen many particular uses of our software from our customers is that the screen printing industry of the flexo and rotogravure industry with excellent results.
I’d say the most amazing results we saw them in the prints that pointed to the reproduction of natural materials such as wood, stone, granite, leather regardless that these reproductions were made in screen printing, flexo or rotogravure.
Being able to reproduce in print such as a wood using the same shade of brown, orange and yellow are actually present in the image it leads to a textural effect and absolutely convincing 3D depth.

In addition, in the process of printing the image in a separate spot color it is much more stable and easy to print as devoid of the typical chromatic drifts of four-color printing in production, with variations of the image toward the yellow, magenta or cyan.

MPA – The polychrome separation spot color is also useful for digital printing ?

COIN – The power of the separation of XerioSEP in N spot colours is also very useful in the case of preparing images for digital textile printing. XerioSEP allows extremely quickly separate inside the image the areas with shades that we want to weaken or highlight from a point of view of colour compared to the other areas of the image. Furthermore, the particular colour mapping algorithm is extremely effective in creating “colourways” for conventional continuous textile printing, as we can see in the image below.

MPA – What is the next step to the colours separation of the image ?
COIN – An image separated for example to 8 colours in Photoshop results as the overlap of 8 levels of colour, in practice we will see on the computer screen an overlay of 8 shades. Now, to reproduce the separate image we are obliged to print overlapping the 8 shades using the silk-screen technique.
Now, to reproduce the separate image we are obliged to print overlapping the 8 shades using the printing technique chosen to be the flexo or screen printing.
The superposition of many screens according to various tests is a potential source of interference problems and optical noise and that’s why in GrafcoAST to get the best possible result we have developed XerioRIP the first RIP can generate original and particular complex screens on both stochastic that hybrid or traditional and that allows you to print in a very precise way (no Moiré effet ) and without defects in flexo and screen printing gradients generated by XerioSEP.
MPA – Which is the visible difference between a separate four-colour printing and a multichrome printing ?
COIN – First of all we should remember that our eye is a wonderful tool and is able to perceive an amount of information at a glance. In general, the four-colour printing appears “flat” and without depth compare to the multichrome printing. Moreover, the reproduction of CMYK colours is decidedly ‘less live’. The largest real difference is evident by comparing prints taken at various stages of the process (for example if we compare some printed matters, the # 200, # 2000, the # 500, and so on).
In CMYK printing we will have a mix of prints with various dominant, sometimes tending to yellow, sometimes red or blue. But this simply is not the case when we use a separation made in multichrome spot color.