Lexmark X500n Service Manual page 121

Lexmark confidential until announce edited 1/4/2007
Step 3: Develop
Once the laser exposes the photodeveloper, the high voltage power supply sends a charge to the developer
roller. The first toner cartridge engages the photodeveloper so it is in contact with the surface. Because of
the charge difference between the toner on the developer roller and the electrostatic image created by the
laser, the toner will cling to the OPC. The toner will only stick where the laser exposed the surface. This is
the develop process.
This process is best illustrated by comparing it to using glue to write on a can and then rolling it over glitter.
The glitter sticks to the glue but won't stick to the rest of the can.
Each toner image is developed and transferred to the photodeveloper one color at a time. The toner image
on the photodeveloper needs to be transferred to the transfer unit before the next color can be developed.
Look at callout 3 in the picture below. This is where the developer rollers in the toner cartridges touch the
surface of the photodeveloper during Step 3 of the EP Process.
Note: If the developer roller is damaged, it will not contact the surface of the photodeveloper properly. The
result could be repeating marks, thin vertical voids or thin vertical lines of color on the printed page. Check
the surface of the developer for damage.
Note: Never touch the surface of the developer roller with your bare hand. The oil from your skin may cause
a charge differential on the surface, and toner will not stick properly. The result would be repeating blotches
of voids/light print on a page. Then the affected cartridge would need to be replaced.
7100-XXX
3-13
Diagnostic aids