Toshiba e-studio 167 Service Manual page 60

- Developer material
The developer material consists of a mixture of the toner and carrier. The toner is charged to the
negative polarity and the carrier to positive polarity due to the friction with each other caused by
mixing.
Toner: Mainly consists of the resin and carbon.
Carrier: Consists of the ferrite and resin coating on
its surface to provide consistent frictional
electrification.
Note:
If the developer material is used for a long time (beyond its normal
life span), the toner is caked onto the carrier.
The charging performance of the carrier is lowered.
Symptom: 1. Image density is lowered.
2. Toner scattering occurs.
3. Background fogging occurs.
Solution: Replace the developer material.
e-STUDIO167/207/237
COPY PROCESS
5-20 µm
Resin ( 90-95% )
[ Toner ]
© 2007 - 2008 TOSHIBA TEC CORPORATION All rights reserved
3 - 6
Carbon
( 5-10% )
Ferrite
30-100 µm
[ Carrier ]
Fig. 3-11
Toner
Carrier
No frictional electrification
occurs on the area where the
toner is caked.
Fig. 3-12