234
For example, low-cost direct thermal media often has very high reaction
temperatures, which means that it
takes a great deal of heat to make a clear
image. Resin ribbons and film media may require higher print
intensity for a
quality image.
The printer provides different ways to increase the heat:
Running the printer slower by changing the print speed via the host or the
Media > Speed menu.
Setting the print intensity to a higher value with the Print Intensity function,
accessed via the host or
through the Media > Image menu. This
causes more heat to be transferred into the media, thereby
generating a
darker image.
The print intensity can be adjusted even higher with the Intensity Shift function, accessed through the
Media > Image menu allowing the actual setting to reach a maximum of 20.
Proper printhead pressure adjustment will affect print quality. To adjust
pressure, rotate the printhead
pressure adjustment dial (see Figure 18). For
more information, refer to Printhead Pressure Adjustment on
page 32
Also, the printhead should be cleaned frequently to ensure that foreign
material does not accumulate on
the printhead and interfere with heat
transfer. If smears, voids, or white lines appear in the printed form, the
printhead should be cleaned with a printhead cleaning pen (see Figure 18).
The cleaning should be done as a matter of routine whenever you install a
new ribbon (thermal transfer
mode) or when you install new media (direct
thermal mode).
Figure 18 Cleaning the Printhead Determining Printhead Wear
The most common signs of a worn printhead are fixed vertical streaks that are
always the same size and in
the same place on the printout. To determine if
vertical streaks are caused by a worn printhead, follow
these methods:
1.
Clean the printhead thoroughly with the printhead cleaning pen. Test
again for vertical streaks.
2.
Remove the printhead (see Replacing the Printhead page 235) and examine it for contamination
or
damage such as scratches, dents, or other marks on the light brown
area containing the heating
elements. Clean and install it, then test again
for vertical streaks.
3.
Load an alternate roll of media. Test again for vertical streaks.
4.
Load an alternate roll of ribbon. Test again for vertical streaks.