Toshiba e-STUDIO2500c, Service Manual, Page: 87 / 402

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May 2006 © TOSHIBA TEC e-STUDIO2500c/3500c/3510c COPY PROCESS
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- About developer material
The developer material is comprised of a mixture of toner and carrier. The toner is charged to a
negative polarity and the carrier to a positive polarity, due to the friction with each other caused
by mixing.
Toner:
Mainly consists of resin and coloring.
Carrier: Consists of ferrite, and over its surface resin coating to provide consistent frictional
electrification.
Fig. 3-13
Note:
If the developer material is used for a long period of time (beyond its normal life span), toner will become
caked onto the carrier.
↓
The performance of the carrier is lowered.
Result:
1. Image density is lowered.
2. Toner scattering occurs.
3. Background fogging occurs.
Solution: Replace the developer material.
Fig. 3-14
Resin (90-95%)
[Toner]
6.8 µm
Ferrite
Carbon
(5-10%)
30-100 µm
[Carrier]
Where toner is caked, no
frictional electrification
occurs.
Toner
Carrier