Epson Stylus Pro 7700 Service Manual page 159

Epson Stylus Pro 7700/7710/7700M/7710M/7900/7910/9700/9710/9900/9910/WT7900/WT7910/9890/9908/7890/7908
Symptom Occurrence condition
Uneven white color • Uneven white color occurs
when storing the CPF with
Coated side
plain paper sheets in
between.
• In the Reverse Print mode,
it occurs to the layered
paper sheet area in color
and white ink.
• Uneven color can be seen
if seen from the printed
side (coated side) in the
Reverse Print mode, but
hard to see if seen from the
side to be viewed (clear
Side to be viewed
film side).
<Reverse Print mode>
Side to be viewed
Uneven color is hard to see
:
Uneven color can be seen.
Scratches on the backside of The backside of the CPF is
the CPF scratched during feeding
because it is fed after the
Release Film is peeled.
TROUBLE SHOOTING
• Different from the white ink used for solvent containing oxidized
titanium, the ingredients of the white ink for Epson Stylus Pro
WT7900/WT7910 are not actually white. As shown below, it is
made of hallow balls that can diffuse the light into white.
Cross-section view of the white ink
• Immediately after printing, the white ink is transparent because it
does not diffuse the light due to the water contained. The ink starts
to look white once the water is absorbed by the CPF.
• When placed between sheets of plain paper before it is dried well or
stored in a high humidity environment in the sandwich structure
mentioned earlier or in a similar case, if plain paper cockles, white
ink may become shaded at the area where plain paper does not
touch the printed side because water in white ink cannot be removed
CPF
well.
Color ink
White ink
Scratches occur if the medium is fed after the Release Film is peeled.
(The Release Film protects the backside because CPF is very
transparent and scratches caused during feeding become conspicuous
easily.)
Remedies for Print Quality Troubles
Cause
Image of diffusion
magnified image
Remedy/Points to be checked
Make sure of the following when storing the CPFs in a pile.
• Avoid storing it in a high-humidity environment.
• After drying the CPF sufficiently for a while, put paper
with high water absorbability such as plain paper with the
CPFs when storing them.
• Put plain paper larger than the CPFs. (If plain paper is not
large enough, white ink becomes thin on the area where
plain paper cannot cover.)
Uneven white color is conspicuous if seen from the printed
side, but hard to see if seen from the side to be viewed in the
Reverse Print mode.
Do not peel the Release Film before printing and drying are
complete.
Revision I
159
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