1.3 Description of Printing Process Techniques
1.3.1 Charging with electricity
In the charging process, the drum surface rotating at a constant speed is charged uniformly with
negative electricity by discharging of RTC (Rubber Tube Charge: Charged film).
This process is performed in parallel for yellow, magenta, cyan and black colors.
The RTC is kept in contact with the drum and rotates following the rotations of the drum.
RTC is a conductive roll, receives discharge voltage from HIGH VOLTAGE POWER SUPPLY
(HVPS) and discharges at minus DC voltage.
The drum surface is uniformly and negatively charged with DC bias voltage.
The drum surface is optical conductor (which is insulator in a dark place and conductor when
receiving light) and the drum inside is composed of conductor.
The Refresher is a conductive brush, and it receives negative DC voltage from the HIGH
VOLTAGE POWER SUPPLY (HVPS) to catch the toner of reverse polarity returned to the drum via
IDT. Also, it removes discharge products.
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Chapter 6 Principles of Operation