Ultra Electronics Ltd
Pronto Maintenance Manual
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SECTION 1
INTRODUCTION TO THE PRINTING PROCESS.
Sublimation uses heating elements in a rigid ceramic Print Head to transfer colour into or onto the PVC plastic surface
from the Dye-Film ribbon. The colours Yellow, Magenta & Cyan are absorbed into the PVC and the Black (K) & Clear
Overcoat are heated onto the Card surface.
Dye Sublimation
Dye Sublimation, or Dye-Sub, is known for it’s high quality photographic output. Dye Sublimation is also known as “Dye
Diffusion” or “Thermal Transfer”.
Inside the Dye Sublimation Printer is a roll of transparent film that resembles sheets of Red, Blue, Yellow, and Black
coloured cellophane bonded together end to end. On one surface of this film are solid dyes corresponding to the four
basic colours used in printing : Cyan, Magenta, Yellow and Black. Between the solid dye and the film, is a layer of
release agent, which controls the amount of dye released at each temperature. The Print Head is heated up as it passes
over the Film, causing the Dye to vaporise and permeate the glossy surface of the PVC Card before returning to solid
form on cooling. This is sublimation.
The Clear Overcoat Layer
The Overcoat layer acts as a protective film against wear and fading and can also carry a secure image, which cannot be
photocopied – e.g. the Magicard “Holokote” security watermark.
Dye Sublimation / Inkjet Printing
There are two factors that contribute to the quality of Dye Sublimation Printers. The first is continuous tone, and the other
is un-dithered colour. In Dye Sublimation printing, colours are not laid down as individual dots, as is done in Inkjet
Printers.
The colour produced by a Dye-Sub Printer is the result of the mixing of pigments
to get the actual colour. This is in contrast to most other printing methods which
use a tight group of coloured dots which, when seen by the human eye from a
distance, appear to be a colour (a process known as “dithering”). Under
magnification, the dots are clearly different colours, and when seen close up with
the naked eye the picture appears grainy. Because only one colour needs to be
printed (instead of up to four), a Dye Sub can place more dots on a card. It can
take a 1200 dpi Printer to get the same resolution a 300 dpi Dye-Sub Printer is
capable of.
Another difference that helps is that because the colour sublimates on the card
instead of being laid down as little dots, the edges of each pixel are blurred.
This gives the impression of blending for a more natural appearance. Dots from
an inkjet Printer leave large white gaps in between pixels, giving the impression
of a grain.
Since longevity is something we all want from our prints, it’s also reassuring to
know that because dyes sublimate instead of just being painted onto it’s surface,
dye sublimation prints resist fading and are colourfast.
ID Card with Overcoat Layer used as a Security Watermark
