Scribing wheel for brittle material and manufacturing method for same, as well as scribing method, scribing apparatus and scribing tool using the same

Abstract

A scribing wheel for a brittle material includes a circumferential ridgeline in which two truncated cones have connected bottoms so as to share a rotational axis. Alternating notches and protrusions are formed along the circumference ridgeline. The protrusion are portions of the ridgeline remaining after the ridgeline is notched. The length of the notches is less than that of the protrusions so that a catch on the surface is improved while lowering the high penetrability.

1 .- 10 . (canceled) 
     
     
         11 . A method for manufacturing a scribing wheel for a brittle material comprising: an outer peripheral portion around which a circumference ridgeline is formed, where two truncated cones have connected bottoms so as to share the same rotational axis; and a number of alternating notches and protrusions which are formed in the direction of the circumference along said circumference ridgeline, wherein
 said protrusions are formed of portions of said circumference ridgeline which remain after said circumference ridge line is notched and have a length in the direction of the circumference so that a scribe line is drawn on said brittle material substrate and a vertical crack extending from the scribe line in the direction of the thickness of a brittle material substrate is formed when the scribing wheel is rotated in such a state as to be pressed against said brittle material substrate, characterized in that   a step of forming a notch having a V shape as viewed in the direction of the axis line of said cones by notching the outer peripheral portion through irradiation with a laser beam is provided in such a manner that the length of said notch in the direction of the circumference is set by changing the center angle of said V shape.   
     
     
         12 . A method for manufacturing a scribing wheel for a brittle material comprising: an outer peripheral portion around which a circumference ridgeline is formed, where two truncated cones have connected bottoms so as to share the same rotational axis; and a number of alternating notches and protrusions which are formed in the direction of the circumference along said circumference ridgeline, wherein said protrusions are formed of portions of said circumference ridgeline which remain after said circumference ridge line is notched and have a length in the direction of the circumference so that a scribe line is drawn on said brittle material substrate and a vertical crack extending from the scribe line in the direction of the thickness of a brittle material substrate is formed when the scribing wheel is rotated in such a state as to be pressed against said brittle material substrate, characterized in that a step of forming a notch having a trapezoid shape as viewed in the direction of the axis line of said cones by notching the outer peripheral portion through irradiation with a laser beam is provided in such a manner that the length of said notch in the direction of the circumference is set by changing the length of the bottom side of the trapezoid shape.