Browse Prior Art Database

Liquid Toner Imaging of Recording Disk Charge Patterns

IP.com Disclosure Number: IPCOM000103058D
Original Publication Date: 1990-May-01
Included in the Prior Art Database: 2005-Mar-17
Document File: 1 page(s) / 34K

Publishing Venue

IBM

Related People

Terris, B: AUTHOR

Abstract

A procedure is disclosed for imaging, with high resolution, the static charge patterns on recording disks.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 100% of the total text.

Liquid Toner Imaging of Recording Disk Charge Patterns

      A procedure is disclosed for imaging, with high resolution, the
static charge patterns on recording disks.

      After flying a recording head over a disk, there is quite often
a pattern of electrical charge left on the disk surface.  This charge
can be measured with commercial electrostatic voltmeters, but higher
spatial resolution measurements can be made with a suspension of
charged particles, such as that found in liquid xerographic
developer.  Liquid developer consists of a liquid solvent and
sub-micron sized toner particles.  In the suspension, the particles
become electrically charged, and will be free to move toward
oppositely charged areas.  By choosing the appropriate liquid
developer, both positively and negatively charged toner can be
obtained.

      To reveal the disk charge pattern, the suspension is poured on
the area to be measured, and the charged particles will be attracted
to oppositely charged areas.  After allowing the liquid to dry, a
high resolution image of the charge patterns remains.  The resolution
is limited by the particle size, which is typically below one micron.
Such images may be useful in evaluating disk performance and
failures.

      Disclosed anonymously.