Magnetic Tape Composition
Magnetic tape is comprised of three elements: the binder (top coat),
magnetic particles, and the backing.
The binder holds the magnetic particles in place, and on the tape
backing. The binder records and stores the magnetic signals written
to it, and determines the frequency responses, sensitivity
distortion, and signal-to-noise ratio. The binder provides a smooth
surface to facilitate transportation of the tape through the
recording system during the record and playback processes. Three
elements are added to the binder to help transport the tape and to
facilitate information playback:
- a lubricant, to reduce friction and tape wear
- a head-cleaning agent to reduce the occurrence of head clogs,
resulting in dropouts
- a carbon black is added to reduce static charges
The substrate (backing film) is needed to support the magnetic
recording layer
An optional back coat is applied to the backside of the substrate
layer. A back coat is used to reduce tape friction, dissipate static
charge, and reduce tape distortion by providing a more uniform tape
wind on the tape reel.
These three elements: binder, magnetic particles, and backing-are
potential sources of failure for a magnetic tape medium. It is
important to maintain your magnetic tape by proper storage and
frequent cleaning and re-certifying.
