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Color
Printers: Dye Sublimation Printing
Dye-sublimation printers allow you to print photo-lab-quality
pictures at home. It employs a printing process that uses heat to
transfer dye to a medium such as a plastic card, printer paper or
poster paper. Dye-sublimation printing does not exhibit the
characteristics of inkjet printing such as individual dots. It
presents a smoother transition between colors and detail producing a
more natural looking image.
The dye
sublimation process is chosen by many for its high quality
photographic results. The dye sublimation printing process which is
also called dye diffusion or dye sub incorporates the use of thermal
transfer to transport varying total of colored dye tincture from a
carrier ribbon or film to the card surface to which the dyes blends
chemically.
 The dye
sub printers use a ribbon film roll that consists of a repeating
sequence of yellow, magenta, cyan, black and clear panels
universally referred to as CMYK. The yellow, magenta and blue panels
include thermally-sensitive dyes parallel to the three basic colors
used in subtractive printing. By combining different amounts of
these dyes, thousands of different colors can be produced: from
white which, has no dye transferred to black which, has full
transfer of each of the three dyes. The black and clear panels are
also used in this thermal printing process, but they function in a
different way called “mass transfer” in which all of the materials
are transferred once the carrier ribbon arrives at the needed
transfer temperature. In this case, a plastic resin rather than a
dye. The black rein panel is used to apply dense black texts and
barcodes on top of the yellow, magenta, and cyan color image, and
the clear panel is used to apply a protective overcoat over the
entire printed image.
The
thermal printing process uses a print head with hundreds of
individual heater elements which, is equivalent to the resolution of
300 dots per inch. Each can be separately managed to transfer
varying amounts of the yellow, magenta, and cyan dyes with all or
none of the black and clear panels as the suitable panel goes by
under the heater element.
The
individual temperature of the elements in the case of yellow,
magenta, and cyan panels causes varying amounts of dye to be
vaporized and to pervade the glossy card surface where they form
bonds with the plastic molecules. This is now what we call the
sublimation process. Sublimation, of course, means to heat something
and vaporize it without going through the liquid phase. This is
because the pigments go from solid, to gas and then back again to
solid, there is little mess as compared to inkjet printing which
uses the liquid state.
Because
of the way the vaporized dyes pervade the card surface, a mild
gradation at the edges of each pixel is created. In addition,
because the color imparts and bonds with the card material, it is
less susceptible to fading and deformation over time.
Gari Vinluan
Technology Correspondent |
