Cbn cutting tool for high-quality, high-efficiency cutting

A CBN cutting tool for high-quality, high-efficiency cutting comprising cutting portions formed by cBN-based sintered bodies, characterized in that each of said cBN-based sintered bodies has an end flank, a side flank, an arcuate nose, a rake face and a negative land formed between said rake face and said arcuate nose, said negative land and said rake face defining a ridgeline therebetween which extends from point Q1 at which said end flank, rake face and negative land intersect each other to point Q2 at which said side flank, rake face and negative land intersect each other, said end flank and said negative land defining a first cutting edge therebetween, said side flank and said negative land defining a second cutting edge therebetween, said first and second cutting edges extending from an apex P of said arcuate nose to points Q1 and Q2, respectively, said first and second cutting edges being the lowest relative to said rake face at said apex P and rising toward points Q1 and Q2, respectively, and wherein a straight line connecting said apex P and point Q1 forms an inclination angle β′ of not less than 20 degrees and not more than 35 degrees with respect to said rake face.