Back to results
US 4,732,813 AGranted
Magnetic recording element
AssigneePD Magnetics, B.V.
InventorsHendrikus F. Huisman, Henricus J. M. Pigmans
Life of this patent
Estimating the term…
Abstract
A magnetic recording element having a carrier and a magnetic coating provided thereon containing a magnetic pigment, a binder and a dispersing agent which is an amine or amide compound containing a sulfuric or sulfonic acid group.
Claims2
A magnetic recording element comprising a carrier and a magnetic coating provided thereon which has a polyester urethane binder, a magnetic pigment and a dispersing agent, the pigment being finely distributed in the binder under the influence of the dispersing agent, characterized in that the dispersing agent is a compound of the following formula:
- ##STR2## or a salt thereof, in which R is an alkyl group or an alkylaryl group having 6-30 C atoms,
- R.sub.1 is a hydrogen atom, alkyl group having 1-4 C atoms or the group --(CH.sub.2 --CH.sub.2 --O).sub.m --(CH.sub.2 --CH.sub.2).sub.n --SO.sub.3 H or a salt thereof,
- m=2-20,
- n=0 or 1, and
- x=0 or 1.
2 more elements
Dependencies are inferred from the claim text.