Toner roller manufacturing method for e.g. electrographic printer, involves compressing oxidation layer in hot water bath with de-ionized water at temperature within specific range during compression process

摘要

The method involves forming an oxide layer in a sulfuric bath on a roller-like base body (12) of aluminum or aluminum alloy, by electrolytic oxidation, where the bath has sulfuric acid within the range of 10 to 20 percent of volume. A direct current (DC) voltage between an anode and a cathode of the base body is increased on the basis of an initial value over time. The oxidation layer is compressed in a hot water bath with de-ionized water at a temperature within the range larger than 90 degree Celsius at duration of eight to twelve minutes during a compression process.