# US 9,751,230 B2 · Razor blades > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,751,230 B2 - Document ID: US9751230B2 - Status: Granted - Kind: B2 - Application number: 14/281,153 - Filed: 2014-05-19 - Published: 2015-11-19 - Granted: 2017-09-05 - Earliest claimed: 2014-05-19 - Assignees: The Gillette Company - Applicants: The Gillette Company - Inventors: Kenneth James Skrobis; Bin Shen; Yongqing Ju; Matthew Robert Stone - Web page: https://patentgrep.com/patent/US9751230B2 ## CPC - B26B 21/56: characterised by the shape - B26B 21/58: characterised by the material - B26B 21/60: by the coating material - B26B: HAND-HELD CUTTING TOOLS NOT OTHERWISE PROVIDED FOR (for harvesting A01D; for horticulture, for forestry A01G; for butchering or meat treatment A22; for manufactering or repairing footwear A43D; nail clippers or cutters A45D29/02; kitchen equipment A47J; {vegetable slicers, julienne cutters and similar devices and holders therefor, B26D3/28}; for surgical purposes A61B; for metal B23D; cutting by abrasive fluid jets B24C5/02; plier-like tools with cutting edges B25B7/22; pincers B25C11/02; handles for hand implements, in general B25G; guillotine-type cutters B26D; {perforating by non-mechanical means, e.g. by fluid jet, B26F1/26}; for erasing B43L19/00; for textile materials D06H) ## Abstract 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=adn 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. ## Claims ### Claim 1 A razor blade comprising: a substrate with a cutting edge being defined by a sharpened tip, said substrate having a thickness of between 1.60 and 1.75 micrometers measured at a distance of four micrometers from the sharpened tip, and a thickness of between 9.25 and 10.00 micrometers measured at a distance of forty micrometers from the sharpened tip. ### Claim 2 (depends on 1) The razor blade of claim 1, further comprising a ratio of the thickness measured at four micrometers to the thickness measured at forty micrometers between 0.165 and 0.185. ### Claim 3 (depends on 1) The razor blade of claim 1, wherein said substrate has a thickness of between 2.70 and 3.00 micrometers measured at a distance of eight micrometers from the sharpened tip, a thickness of between 4.44 and 5.00 micrometers measured at a distance of sixteen micrometers from the sharpened tip, a ratio of the thickness measured at four micrometers to the thickness measured at eight micrometers between 0.56 and 0.62, and a ratio of the thickness measured at four micrometers to the thickness measured at sixteen micrometers between 0.32 and 0.40. ### Claim 4 (depends on 1) The razor blade of claim 1, wherein a cross-sectional shape of the blade is defined by the equation w=adn, where “a” is in the range of 0.50 to 0.62, and “n” is in the range of 0.76 to 0.80. ### Claim 5 (depends on 1) The razor blade of claim 1, wherein the substrate comprises a martensitic stainless steel of between 0.35% and 0.6% C and between 13% and 14% Cr. ### Claim 6 (depends on 5) The razor blade of claim 5 wherein said substrate further comprises between 1.1% and 1.5% Mo. ### Claim 7 (depends on 1) The razor blade of claim 1 wherein the substrate is a martensitic stainless steel having a carbide density of at least 200 carbides or more per 100 square micrometers as determined by optical microscopic cross-section. ### Claim 8 (depends on 1) The razor blade of claim 1 wherein the substrate has a tip radius of in the region of 125 to 500 angstroms. ### Claim 9 (depends on 8) The razor blade of claim 8 further comprising an interlayer joined to said substrate. ### Claim 10 (depends on 9) The razor blade of claim 9 wherein said interlayer comprises niobium, chromium, platinum, titanium, or any combination or alloys thereof. ### Claim 11 (depends on 10) The razor blade of claim 10, further comprising a coating layer joined to said interlayer. ### Claim 12 (depends on 11) The razor blade of claim 11 wherein said coating layer comprises carbon or aluminum magnesium boride. ### Claim 13 (depends on 12) The razor blade of claim 12 further comprising an overcoat layer joined to said coating layer. ### Claim 14 (depends on 13) The razor blade of claim 13 wherein said overcoat layer comprises chromium. ### Claim 15 (depends on 13) The razor blade of claim 13 further comprising an outer layer joined to said overcoat layer. ### Claim 16 (depends on 15) The razor blade of claim 15 wherein said outer layer comprises a polymer. ### Claim 17 (depends on 16) The razor blade of claim 16 wherein said outer layer comprises polytetrafluoroethylene. ### Claim 18 (depends on 12) The razor blade of claim 12 further comprising an outer layer joined to said coating layer. ### Claim 19 (depends on 1) The razor blade of claim 1, further comprising an included angle that is less than 7 degrees. ### Claim 20 (depends on 19) The razor blade of claim 19 wherein said included angle is measured at a distance of forty micrometers or greater from the sharpened tip. ### Claim 21 (depends on 19) The razor blade of claim 19 wherein said substrate has only two facets on each side of said cutting edge. ### Claim 22 (depends on 1) The razor blade of claim 1, further comprising a nitride region disposed at or beneath a surface of the substrate. ### Claim 23 (depends on 22) The razor blade of claim 22 wherein said nitride region is formed by plasma nitriding. ### Claim 24 (depends on 23) The razor blade of claim 23 further comprising one or more layers joined to said nitride region.