| 摘要 |
<p>The amount of adhesion of cullet to the major planar surface of a glass substrate due to the grinding of an end surface is reduced. An end surface (12) of a glass substrate (10) is ground into an elliptical shape. The ellipse is defined by the ratio of a long side (a) and a short side (b) and is formed into a continuous elliptical curved surface by the curvature radius (R1) of an upper curved surface (12a), the curvature radius (R2) of a lower curved surface (12b), and the curvature radius (R3) of an intermediate curved surface (12c). The curvature radiuses (R1-R3) have the relationships of R1 = R2, and R2 = R3 or the relationships of R1 = R2, R3 > R2, and R3 > R1. The distance (c) from the center (O) of the end surface (12) to the boundaries (P) at which tangential lines (S1, S2) depart from the major planar surface of the substrate (10) is less than the distance in conventional cases in which the end surface (12) is chamfered or formed into a semicircular shape. The configuration changes the direction of scatter of cullet, which is produced in the step of end surface grinding, to cause the cullet to scatter further toward the end surface (12) side, and as a result, the amount of adhesion of the cullet to the major planar surface (14) of the glass substrate (10) is reduced.</p> |
