Digital BW, The Print

Hi folks,

Even though the level of expertise of the contributors to this list is
very high, there may be others who, like myself, are just getting
started. I recently received an explanation of pigment vs. dye from a
company that sells ink, including WJ1082 (aka Eboni K). The explanation
helped me to understand more clearly; perhaps it will help others. I
asked him for his permission to post it here. I have no affiliation with
Mr. Lewis, except as a potential customer.

Andrew


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The dye in the dye-based ink dissolves in water like sugar does
in water -- completely.  Pigment does not dissolve completely. It
is more like a flour and water mixture.  Because of this,
dye-based inks flow better and have been the standard in inkjet
printers. But the dye will re-dissolve and the ink will flow
across the paper if drops of water hit the paper.

Pigmented ink particles tend to settle into the tiny fibers that
make up the paper.  As the ink dries, the pigment particles get
stuck in the fibers. Thus, the pigmented inks are more water
resistant than the dye-based inks. Only about 5 to 10 percent of
the ink will re-flow if the paper is hit by water.

The molecules in dye-based inks are spread out. You might think
of dye-based ink on paper as similar to a beach covered with
sand. Because of this, dye-based ink tends to fade quicker, since
all of the molecules are exposed to the chemical and
sunlight-caused reactions that fade the ink. You may notice
fading of dye-based inks exposed to direct sunlight commonly in 6
to 12 months.

Pigment particles are similar to large pebbles on a beach. It is
much more difficult for sunlight and chemicals to react with all
of the pigment molecules, since most of them are hidden inside
the "pebbles". Pigmented inks will usually last for many years
before fading becomes noticeable.

It is possible to get more "color" into pigments than into dyes.
Therefore, pigmented colors tend to be more vibrant than
dye-based colors. And pigmented black inks tend to be slightly
darker than dye-based inks.

Sincerely, Gordon Lewis
The Printer Filling Station
www.PrinterFillingStation.com
1403 Shiloh Oak Drive
Loganville, Georgia 30052
Office 1-800-404-4923

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