The latest digital printing systems have made it possible to process even individual items most efficiently and in high quality.
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Digital printing techniques have not only revolutionised advertising technology. The ease of use of the comparatively compact, low-cost and lowmaintenance printing systems, even in large format, now provides companies in all industries with on-demand production without depending on specialised print service providers. Maximum flexibility and an immense increase in efficiency through faster, cost-effective in-house procedures are therefore guaranteed.
"Direct Printing Know-How" offers background information especially to those who are new to this innovative field. Should you have specific questions, please do not hesitate to contact us by phone (0049-7843/9933150).
Digital direct printing is a non-contact inkjet printing method which produces high resolution print images in photo realistic quality and can be used for the processing of a variety of materials. The digital printing data is edited in a standard graphics programme and sent by mouse click from the PC to the printing system. Pre- or post-treatment of substrates is usually not necessary.
Using a desktop printer has long been second nature: Just create a text or image file on a PC, insert paper, enter print command and immediately the illustration on the screen is reproduced by the printer. That is digital printing in its simplest form using a paper medium.
The operation of a digital direct printing system is just as easy. The print data is created in a standard graphics program, the print material is positioned on the flatbed table of the machine and the printing process is started with a mouse click on the PC. A few additional technical details about the handling of the device are provided during a brief training session on the day of installation. Apart from that, no print-based knowledge is needed to start digital direct printing.
Manufacturers of digital printing systems have adapted their machinery in many different ways in order to make the printing process more environmentally friendly. The use of low-odour eco inks, various kinds of refill systems, low ink mileage due to the creation of efficient, highly accurate printheads as well as the conversion from energy-wasting UV-lamps to UV-LEDs are just some of the many measures printer producers have adopted so far. Furthermore software companies also provide various solutions to make digital printing greener.
The body colours CMYK (Cyan, Magenta, Yellow and Black/Key) are used in printing. Instead of being luminescent they reflect or absorb white light components. Unlike the light colours RGB (red, green and blue) that are used to display images on monitors (e.g. PC, TV, digital camera) body colours are not transparent but translucent. As the combination of Cyan, Magenta and Yellow does not create a deep black, Key is added as the fourth colour. Printing data always must be created in the CMYK colour space.
Digital direct printing allows you to work with an almost unlimited variety of materials. The opacity and bonding of colours on individual material types as well as resistance against chemical, mechanical and other influences are predominantly dependent on the specialist properties of the inks. Please find a detailed list of available direct printing inks here.
Direct printing inks are translucent. As a result they are affected by the surface colour they are printed on and can therefore differ from their original colour if the substrate is not pure white. In order to get accurate colours and optimal opacity on transparent materials or coloured surfaces, the required white background is simulated using a white ink layer over or under the colour. Digital UV direct printing allows this and thereby creates new opportunities, not only for the processing of promotional items but also for industrial applications, such as plastic or metal processing. (Please find corresponding machinery here.)
Special colours, such as RAL, Pantone or HKS-tones, are individually produced. While the printing system usually creates the required colours during the printing process by blending the body colours CMYK, special colours are used as individual tones. They are often used in packaging production or for logo printing.
As a general rule, specialist colours can only be approximately reproduced in digital direct printing. It might be necessary to create particular colour profiles for varying material or ink types which we will gladly assist you with, if required. (Please find details about colour profiling here.)
In the past inkjet printers, particularly older generation models, could only print ink droplets of equal size. In order to create light colours, the distance between the individual ink drops in the picture grid had to be enlarged, leaving tiny uncovered gaps which made the colour tone in those areas seem lighter. Unfortunately, this method caused visual impurities.
As of the mid-1990s, 6-colour printers using the additional inks Light-Cyan and Light-Magenta enabled the printing of light coloured passages with high density while also satisfying the required quality.
Since then, much has changed. Thanks to variable dot size technology it is now possible to achieve outstanding print results in high-resolution photo quality, even with 4-colour printers, due to the close arrangement of variably sized ink droplets. Using this technology, high contour accuracy, smooth gradients and quarter-tones as well as crisp colours in the mid tones and incredible density in shadows and areas of solid colour are guaranteed.
You can rely on excellent picture quality for your graphics, photos, art pieces, drawings etc. when they are printed on a digital direct printing system. This high image quality results from the use of Piezo inkjet printheads.
This particular printhead technology, developed by EPSON, uses ceramic piezo elements firing ink from the printhead when voltage is applied. As this is a mechanical process, you can precisely control the amount of ink fired. At only 5 microseconds, the so-called impulse duration is extremely short. One printhead nozzle (out of up to 3,600 nozzles in total – depending on the printer model) can fire between 20,000 and 30,000 times per second. Hence, the printhead controls several million processes per second when printing, for example, a multi-coloured image.
Piezo inkjet printheads are able to create ink droplets of just a few picolitres (1 pl = 1 trillionth of a litre). As a result, the dot size is so small that it is invisible to the human eye from a normal distance. This ensures maximum precision and smooth colour gradation. Furthermore, they are extremely durable. So they are particularly suitable for the tough conditions found in the industrial printing world.