Patent ID: 8323301

Claim:
A medical knife having a cutting edge formed along the outer periphery of a blade portion comprising: (a) a shank; and (b) a blade portion formed contiguously with the shank, the blade portion comprising: (i) a tip portion including a tip whose projected plane shape is formed at an extreme end of the blade portion; (ii) a maximum width portion having a largest width; (iii) a side surface portion formed between the tip portion and the maximum width portion; (iv) a cutting edge defining an outer periphery of the blade portion; (v) a first slanting surface formed along the cutting edge; and (vi) a second slanting surface formed inside the first slanting surface and formed along the first slanting surface, wherein the first slanting surface constituting the tip portion has a width larger than that of the first slanting surface constituting the side surface portion; wherein a sectional shape of the cutting edge in the tip portion of the blade portion is formed of a first curved slanting surface swelled upward and a surface intersecting the first slanting curved surface.