Patent ID: 7284461

Claim:
A method of manufacturing a razor blade comprising; a. subjecting a continuously moving, stainless steel blade material to a high temperature hardening process wherein said hardening process comprising the sequential steps of 1) ramping said blade material up to said high temperature upon entrance to a furnace; 2) austenizing said blade material by maintaining said blade material at said high temperature for a period of time in said furnace through which a forming gas flows; 3) lowering the temperature of said blade material prior to oxidation and prior to exiting said furnace through which said forming gas is flowing; 4) immediately oxidizing the blade material to form an uniform oxide layer on the blade material; b. quenching the blade material, after the oxidizing step, to initiate martensitic transformation to harden the blade material; and c. forming the hardened blade material into a razor blade, the oxide layer providing the razor blade with a colored surface.