Magnetic recording medium having a metallic magnetic thin film layer, a primer layer comprising an amino alkoxysilane and a lubricant layer comprising a functional perfluoropolyether
AssigneeMinnesota Mining and Manufacturing Company
InventorsColin F. W. Norman, Timothy G. E. Swales
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Abstract
A two-layer protective coating covers a metallic thin film magnetic recording medium of a magnetic recording element. The two-layer protective coating comprises a primer layer proximal to the metallic thin film magnetic recording medium. The primer layer comprises an amino functional alkoxy silane and a copolymerizable monomer. The copolymerizable monomer comprises a plurality of vinyl groups. The two-layer protective coating also comprises a lubricant layer distal from the metallic thin film magnetic recording medium. The lubricant layer comprises a functional perfluoropolyether.
Claims11
A magnetic recording element, comprising:
- (a) a substrate;
- (b) a metallic thin film magnetic recording medium deposited onto the substrate;
- and
- (c) a protective coating deposited directly onto the metallic thin film magnetic recording medium, said protective coating comprising:
- (i) a primer layer proximal to the metallic thin film magnetic recording medium, said primer layer comprising an amino functional alkoxy silane and a copolyermisable monomer which comprises a plurality of vinyl groups;
- and
- (ii) a lubricant layer distal from the metallic thin film agnetic recording medium, said lubricant layer comprising a functional perfluoropolyether, wherein the functional perfluoropolyether is of the formula:
- Q(R.sub.f).sub.k C.sub.a F.sub.2a -Z,
- wherein:
- Q comprises a non-fluorinated chain which is terminated by an unsaturated polymerisable gruop;
- R.sub.f represents a chain of two or more randomly distributed perfluoroalkylene oxide units;
- Z is selected from the group consisting of:
- --OC.sub.a F.sub.2a+1 and Q;
- a is independently an integer of 1 to 4;
- and
- k is an integer from 2 to 300.
Dependencies are inferred from the claim text.