Ricoh FT5535 Service Manual page 482

TECHNICAL SERVICE BULLETIN
CUSTOMER SERVICE GROUP
BULLETIN NUMBER: 4027/4527/5035/5535/4022/4522 - 037 06/13/97
APPLICABLE MODEL: FT4027/4527/5035/5535/4022/4522
SUBJECT: DRUM FILMING WITH TONER
SYMPTOM:
The OPC Drum becomes covered with a black substance, most likely toner, after 8K to 20K copies. The
surface of the Drum looks as if is being coated by toner in a width equal to that of the paper or th e
Development Roller. As a result, dirty background appears all over the copy.
CAUSE:
The additives contained in acid paper called talc (MgO SiO2) is causing a filming problem.
The talc is characteristically negatively charged. The talc is electrically combined with the posit ively charged
toner and adheres to the Drum surface in the non-image areas. Once on the Drum, toner and talc
compound is combined and pressed down by the Transfer Belt and Charge Roller. This leads to a gradu al
build-up on the Drum surface. The talc on the Drum surface is then carried to the Development Unit and
then accumulates there. This accumulation of talc accelerates the filming problem in an area the wi dth of
the Development Roller.
Coated with toner
SOLUTION:
Change the type of paper used from an acid type to a neutral type. The type of paper can be checked in the
following manner.
1. Use the check pen. (The part number will be available soon.)
NOTE: Once this problem occurs, the Drum and Developer in the Development Unit must be replaced and
the Transfer Belt must to be cleaned.