Black Over Print; Black Over Print Disabled; Black Over Print Enabled - Ricoh G108 Service Manual

CONTROLLER

6.11.4 BLACK OVER PRINT

Black Over Print prevents unexpected white lines from showing when black letters
or lines are printed with color background. You can enable or disable this feature
from the printer driver (default: disabled). This process is similar to "trapping" which
is used for production color printing.
When Black Over Print is enabled, the user may experience these limitations:
• Text or image sharpness can deteriorate because the black toner spreads
out into the color area.
• More toner is consumed.
• The background color is slightly visible on the black letters or lines.

Black Over Print Disabled

Black lines and color background
are printed as follows:
1. Imagine a text character,
located in a red field. After
development, the black toner
[A] is transferred to transfer
belt [B].
2. The color toner (for example,
magenta [D] and yellow [C])
is then, after development in
sequence, also transferred to
the transfer belt. If the line position of the black toner was not correct, an
undesirable white line (void area) [E] will appear in the background color of the
final image. (In our example, a white space would be visible in the red
surrounding field of the text "1".)

Black Over Print Enabled

Black lines and color background
are printed as follows:
1. With Black Over Print enabled,
the black latent image was
created with a pre-determined
amount of "over-print" included.
After black development, the
black toner [A] is transferred to
transfer belt [B].
2. When the color toners, in our example Magenta [D] and Yellow [C] are applied
to the transfer belt in sequence, with black overprint, the colors slightly overlap
onto the black toner. As a result of this over-print, even if the line position of
the black toner is not correct, the undesirable white line (void area) will not be
present when transferred to the paper and fused.
G108
[A]
1
[E]
[A]
1
1
6-48
[B]
[C]
[D]
[B]
[C]
[D]
G108D963.WMF
SM