Compensated molds for manufacturing ion exchange strengthened, 3D glass covers

Patent metadata

Field	Value
Publication number	US-9779190-B2
Application number	US-201615041857-A
Country	US
Kind code	B2
Filing date	Feb 11, 2016
Priority date	May 7, 2013
Publication date	Oct 3, 2017
Grant date	Oct 3, 2017

Abstract

Methods for compensating for the warp exhibited by three-dimensional glass covers as a result of ion exchange strengthening are provided. The methods use a computer-implemented model to predict/estimate changes to a target three-dimensional shape for the 3D glass cover as a result of ion exchange strengthening. The model includes the effects of ion exchange through the edge of the 3D glass cover. In an embodiment, the inverse of the predicted/estimated changes is used to produce a compensated (corrected) mold which produces as-molded parts which when subjected to ion exchange strengthening have shapes closer to the target shape than they would have had if the mold had not been compensated (corrected).

First claim

What is claimed is:

1. A process for making a mold's molding surface comprising producing the molding surface based at least in part on computer-implemented modeling that predicts/estimates changes in a target shape of a three-dimensional glass cover resulting from ion exchange strengthening, said ion exchange strengthening comprising ion diffusion and said glass cover comprising a planar central portion and a perimeter portion which (i) borders at least part of the planar central portion and (ii) extends out of the plane of the planar central portion to provide the glass cover with three dimensionality, said perimeter portion having a perimeter edge,
wherein:
(a) said computer-implemented modeling comprises modeling the effects of ion exchange through the perimeter edge by employing a boundary condition at the perimeter edge; and
(b) in said computer-implemented modeling, said boundary condition permits ion permeation through the edge.

2. The process of claim 1 wherein in said computer-implemented modeling, the boundary condition at the perimeter edge specifies a constant ion concentration at the edge.

3. The process of claim 1 wherein in said computer-implemented modeling:
(i) ion diffusion is treated as thermal diffusion; and
(ii) based on said treatment of ion diffusion as thermal diffusion in the modeling, the boundary condition at the perimeter edge is treated as permitting heat flow through the edge.

4. The process of claim 3 wherein in said computer-implemented modeling, the boundary condition at the perimeter edge specifies a constant temperature at the edge.

5. The process of claim 1 wherein in said computer-implemented modeling, a mesh is employed and the mesh has a size at the perimeter edge in the range of five to ten microns.

6. The process of claim 1 wherein in said computer-implemented modeling, ion exchange through the perimeter edge results in predicted/estimated changes to the target three-dimensional shape of a larger magnitude than ion exchange through the remainder of the outer surface of the glass cover.

Assignees

• Corning Inc

Inventors

• Ahmed Izhar Zahoor
• Gaylo Keith Raymond
• Immerman Jacob
• Ridge John Richard
• Saltzer Jr John Robert
• Ukrainczyk Ljerka

Classifications

• G06F17/10

  Complex mathematical operations {(function generation by table look-up G06F1/03; evaluation of elementary functions by calculation G06F7/544)} · CPC title

• C03B23/0357

  by suction without blowing, e.g. with vacuum or by venturi effect · CPC title

• H05K5/03

  Covers · CPC title

• C03C21/002 Primary

  to perform ion-exchange between alkali ions (C03C21/005 takes precedence) · CPC title

• G06F30/20 Primary

  Design optimisation, verification or simulation (optimisation, verification or simulation of circuit designs G06F30/30) · CPC title