Mechanical scoring and separation of strengthened glass
AssigneeCorning Incorporated
InventorsJohn Frederick Bayne, James William Brown, Michael Albert Joseph, II, Siva Venkatachalam, Sujanto Widjaja
Life of this patent
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Abstract
A strengthened glass sheet is separated into undamaged sheet segments by mechanically scribing one or more vent lines of controlled depth into the sheet surface, the depths of the scribed lines being insufficient to effect sheet separation, and then applying a uniform bending moment across the vent lines to effect separation into multiple sheet segments, the vent lines being scribed from crack initiation sites comprising surface indentations formed proximate to the edges of the glass sheet.
Claims18
A method for scribing a chemically strengthened glass sheet comprising the steps of:
- forming a plurality of crack initiation sites in a first surface and proximate to a first edge of a chemically strengthened glass sheet using a first rotating abrasive scoring wheel, the chemically strengthened glass sheet comprising a surface compression layer of layer depth DOL and each crack initiation site comprising a surface indentation extending into the first surface;
- and
- following the formation of the plurality of crack initiation sites, mechanically scoring the first surface from the plurality of crack initiation sites toward a second edge of the chemically strengthened glass sheet to scribe a plurality of vent lines that extend along the first surface and into the chemically strengthened glass sheet to a vent depth at least equal to DOL but less than a fracture depth without causing self-separation of the chemically strengthened glass sheet, wherein a vent line extending to the fracture depth would cause self-separation of the chemically strengthened glass sheet.
Dependencies are inferred from the claim text.