| 摘要 |
PROBLEM TO BE SOLVED: To provide a break bar used for a break device which can break, suitably and easily without requiring a previous process, a laminate fragile material substrate formed by laminating layers composed of resin or metal on a principal surface of the fragile material substrate.SOLUTION: A break bar used for a break device which breaks a laminated fragile material substrate formed by providing a dissimilar material layer composed of resin or metal on one principal surface of the fragile material substrate and forming a scribe line on the other principal surface, from a dissimilar material layer side along the scribe line. The break bar has two blade surfaces in which tips of the break bar, coming in contact with the laminated fragile material substrate during breaking, form an angle of 50 degrees or smaller and further has another blade surface consisting of a curved surface having an arc cross section of a curvature radius of 5 μm or smaller, or a flat surface having a linear cross section of width of 10 μm or smaller between the two blade surfaces. |
