Laser printer photoreceptors (drums, belts, etc) are coated with various
materials chosen for their suitability for retaining a static charge.
The big Xerox series I spent a lot of time wokring on used selenium doped
with arsenic, IIRC...  nasty stuff if you need to polish one out as I have
done countless times.  Anyway, copper would disrupt things pretty much
completely.

Hard drive platters are coated with a "paint" made with microscopic
particles of various metal oxides, it's those that hold the magnetic
charge.  The platter itself is non-magnetic (aluminum, magnesium or
glass).

Dale
---
We are Dyslexia of Borg.
Fusistance is retile.
Your ass will be laminated.

On Wed, 13 Nov 2002, Richards, Justin P wrote:

> How is it done on the Drum.  I thought they were metallic also.  I also
> wonder how they have different magnet moment polarities so close together on
> a Hard drive platter.

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