Razor blade technology

A razor blade comprising a substrate with a wedge-shaped edge defined by a sharpened tip and facets that have an included angle of less than seventeen degrees at a distance of forty micrometers from the sharpened tip, a layer of niobium on the tip and flanks of said wedge-shaped edge, the thickness of said niobium layer being in the range of about 50-500 angstroms, and a layer of diamond or diamond-like carbon material on said niobium layer, said layer of diamond or diamond-like carbon material having a thickness in the range of twelve hundred to eighteen hundred angstroms from the sharpened tip of said substrate to a distance of forty micrometers from the sharpened tip, and an ultimate tip defined by facets that have lengths of at least about 0.1 micrometer and define an included angle of at least sixty degrees, a radius at the ultimate tip of said diamond or diamond-like material of less than 400 angstroms, and an aspect ratio in the range of 1:1-3:1, a hardness of at least thirteen gigapascals and an L5 wet wool felt cutter force of less than 0.8 kilogram, and dry wool felt (ten cuts) edge damage of less than fifty small edge damage regions and no damage regions of larger dimension or depth.

A shaving unit comprising support structure that defines spaced skin-engaging surfaces, and razor blade structure secured to said support structure, said razor blade structure including a substrate with a wedge-shaped edge defined by a sharpened tip and facets that have an included angle of less than seventeen degrees at a distance of forty micrometers from the sharpened tip;

• and a layer of diamond or diamond-like carbon material on said wedge-shaped edge, said layer of diamond or diamond-like material having a thickness in the range of twelve hundred to eighteen hundred angstroms from the sharpened tip of said substrate to a distance of forty micrometers from the sharpened tip, and an ultimate tip defined by facets that have lengths of at least about 0.1 micrometer and define an included angle of at least sixty degrees, a hardness of at least thirteen gigapascals, an L5 wet wool felt cutter force of less than 0.8 kilogram, and dry wool felt (ten cuts) edge damage of less than fifty small edge damage regions and no damage regions of larger dimension or depth, said diamond or diamond-like carbon coated wedge-shaped edge being disposed between said skin-engaging surfaces.

A razor blade comprising a substrate with a wedge-shaped edge defined by a sharpened tip and facets that have an included angle of less than seventeen degrees at a distance of forty micrometers from the sharpened tip, and a layer of strengthening material on said wedge-shaped edge, said layer of strengthening material being at least twice as hard as said substrate and having a thickness of at least twelve hundred angstroms from the sharpened tip of said substrate to a distance of forty micrometers from the sharpened tip, and an ultimate tip defined by facets that have lengths of at least about 0.1 micrometer and define an included angle of at least sixty degrees, a hardness of at least thirteen gigapascals, an L5 wet wool felt cutter force of less than 0.8 kilogram, dry wool felt (ten cuts) edge damage of less than ten small edge damage regions and no damage regions of larger dimension or depth, a radius at the ultimate tip of said diamond or diamond-like material of less than 400 angstroms and an aspect ratio in the range of 1:1-3:1.