An integrally formed rigid razor blade having a body with a cutting edge portion extending about a cutting edge portion plane, and having a cutting edge at one end, a base portion extending along a base portion plane, a bent portion intermediate the cutting edge portion and the base portion. The body is made of martensitic stainless steel that includes mainly iron and between 0.62% and 0.75% of carbon in weight.

An integrally formed rigid razor blade having a body with a cutting edge portion extending about a cutting edge portion plane, and having a cutting edge at one end, a base portion extending along a base portion plane, a bent portion intermediate the cutting edge portion and the base portion. The body is made of martensitic stainless steel that includes mainly iron and between 0.62% and 0.75% of carbon in weight.

The present invention generally relates to blades for utility knives, craft knives, box cutters, and other cutting tools. Specifically, this invention relates to cutting blades manufactured from ceramics.

The present invention generally relates to blades for utility knives, craft knives, box cutters, and other cutting tools. Specifically, this invention relates to cutting blades manufactured from ceramics.

A razor blade including a substrate with a cutting edge, the substrate includes a mixed nitride-substrate interregion disposed at or beneath a surface of the substrate, the mixed nitride-substrate interregion being substantially free of a compound layer.

A razor blade having a substrate with a cutting edge being defined by a sharpened tip. The substrate has thicknesses of 1.60-1.75 micrometers and 9.25-10.00 micrometers measured at a distance of four and forty micrometers from the blade tip, respectively. A ratio of the thickness measured at four micrometers to the thickness measured at forty micrometers is between 0.165-0.185. The substrate thickness is about 2.70-3.00 micrometers at eight micrometers from the blade tip, about 4.44-5.00 micrometers at sixteen micrometers from the blade tip with a thickness ratio measured at four micrometers and eight micrometers between 0.56-0.62, and a thickness ratio measured at four micrometers and sixteen micrometers between 0.32-0.40. The blade edge shape is defined by equation w=ad.sup.n where a is between 0.50-0.62 and n is between 0.76-0.80. An included angle of less than 7 is measured at a distance of forty micrometers or greater from the blade tip. A nitrided substrate may also be provided.

A razor blade having a substrate with a cutting edge being defined by a sharpened tip. The substrate has thicknesses of 1.60-1.75 micrometers and 9.25-10.00 micrometers measured at a distance of four and forty micrometers from the blade tip, respectively. A ratio of the thickness measured at four micrometers to the thickness measured at forty micrometers is between 0.165-0.185. The substrate thickness is about 2.70-3.00 micrometers at eight micrometers from the blade tip, about 4.44-5.00 micrometers at sixteen micrometers from the blade tip with a thickness ratio measured at four micrometers and eight micrometers between 0.56-0.62, and a thickness ratio measured at four micrometers and sixteen micrometers between 0.32-0.40. The blade edge shape is defined by equation w=ad.sup.n where a is between 0.50-0.62 and n is between 0.76-0.80. An included angle of less than 7 is measured at a distance of forty micrometers or greater from the blade tip. A nitrided substrate may also be provided.

A razor blade having a substrate with a cutting edge being defined by a sharpened tip. The substrate has thicknesses of 1.60-1.75 micrometers and 9.25-10.00 micrometers measured at a distance of four and forty micrometers from the blade tip, respectively. A ratio of the thickness measured at four micrometers to the thickness measured at forty micrometers is between 0.165-0.185. The substrate thickness is about 2.70-3.00 micrometers at eight micrometers from the blade tip, about 4.44-5.00 micrometers at sixteen micrometers from the blade tip with a thickness ratio measured at four micrometers and eight micrometers between 0.56-0.62, and a thickness ratio measured at four micrometers and sixteen micrometers between 0.32-0.40. The blade edge shape is defined by equation w=ad.sup.n where a is between 0.50-0.62 and n is between 0.76-0.80. An included angle of less than 7 is measured at a distance of forty micrometers or greater from the blade tip. A nitrided substrate may also be provided.

A razor blade having a substrate with a cutting edge being defined by a sharpened tip. The substrate has thicknesses of 1.60-1.75 micrometers and 9.25-10.00 micrometers measured at a distance of four and forty micrometers from the blade tip, respectively. A ratio of the thickness measured at four micrometers to the thickness measured at forty micrometers is between 0.165-0.185. The substrate thickness is about 2.70-3.00 micrometers at eight micrometers from the blade tip, about 4.44-5.00 micrometers at sixteen micrometers from the blade tip with a thickness ratio measured at four micrometers and eight micrometers between 0.56-0.62, and a thickness ratio measured at four micrometers and sixteen micrometers between 0.32-0.40. The blade edge shape is defined by equation w=ad.sup.n where a is between 0.50-0.62 and n is between 0.76-0.80. An included angle of less than 7 is measured at a distance of forty micrometers or greater from the blade tip. A nitrided substrate may also be provided.

The present invention generally relates to blades for utility knives, craft knives, box cutters, and other cutting tools. Specifically, this invention relates to cutting blades manufactured from ceramics.