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.
Claims23
A method for scribing a strengthened glass sheet comprising the steps of:
- forming a crack initiation site in a first surface and proximate to a first edge of a glass sheet, the sheet comprising a surface compression layer of layer depth DOL and the crack initiation site comprising a surface indentation extending into the first surface;
- and
- mechanically scoring the first surface from the crack initiation site a toward a second edge of the glass sheet to scribe a vent line extending into the first surface to a vent depth at least equal to DOL but less than a fracture depth causing separation of the glass sheet.
A method of separating a strengthened glass sheet incorporating surface compression layers into two or more sheet sections comprising the steps of:
- scribing a vent line extending into the first surface to a vent depth at least equal to a depth DOL corresponding to the depth of a surface compression layer on the first surface, but less than a fracture depth causing separation of the glass sheet;
- and
- applying a uniform bending moment across the vent line of a magnitude sufficient to separate the glass sheet along the vent line.
Dependencies are inferred from the claim text.