Glass strengthening method and method for manufacturing electronic device housing

Abstract

Disclosed is a tempered glass, a glass tempering method, and an electronic device housing. Both surfaces of the tempered glass located on opposite sides have a surface compressive stress layer, and a third stress layer is further interposed between the two surface compressive stress layers, the third stress layer includes a compressive stress region (32) and a plurality of tensile stress regions (40) spaced apart within the compressive stress region (32), the plurality of tensile stress regions (40) are arranged in a direction perpendicular to the thickness direction of the tempered glass, the compressive stress region (32) goes around each tensile stress region (40), and the sum of the depths of the two surface compressive stress layers and the compressive stress region (32) located between two adjacent tensile stress regions (40) is equal to the thickness of the tempered glass.

Claims

1. A step of forming a plurality of shielding layers (20) distributed at intervals on a first surface and a second surface located on opposite sides of a glass substrate (10), wherein the shielding layer (20) on the first surface and the shielding layer (20) on the second surface correspond to each other in a one-to-one manner, The first step of chemically strengthening the glass substrate (10) with the shielding layer to form the original compressive stress layer (30) on the surface of the glass substrate (10) covered by the shielding layer (20), on the surface of the glass substrate (10) not covered by the shielding layer (20), and inside the glass substrate (10), and to form a plurality of tensile stress regions (40) inside the glass covered by the shielding layer (20), wherein the tensile stress regions (40) are surrounded by the original compressive stress layer (30), and the depth of the original compressive stress layer (30) not covered by the shielding layer (20) is equal to the thickness of the glass substrate (10), The steps include removing the shielding layer (20), A glass strengthening method characterized by comprising the step of performing a second chemical strengthening on the glass substrate (10) from which the shielding layer (20) has been removed to obtain tempered glass.

2. The glass strengthening method according to claim 1, characterized in that the total coverage rate of the multiple shielding layers (20) on the first surface or the second surface is 10% to 70%.

3. The glass strengthening method according to claim 1, characterized in that the number of shielding layers (20) on the first surface or the second surface is three or more.

4. The glass strengthening method according to claim 1, characterized in that, when the thickness of the glass substrate (10) is 0.5 mm or more, the strengthening time for the first chemical strengthening is 300 min or more.

5. The glass strengthening method according to claim 1, characterized in that a sodium-containing molten salt is used in the first chemical strengthening step and the strengthening temperature is 350°C to 440°C.

6. The glass strengthening method according to claim 1, characterized in that a potassium-containing molten salt is used in the second chemical strengthening step and the strengthening temperature is 350°C to 440°C.

7. The glass strengthening method according to any one of claims 1 to 6, characterized in that the strengthening time for the second chemical strengthening is 10 min to 200 min.

8. A method for manufacturing an electronic device housing, characterized by including a glass strengthening method according to any one of claims 1 to 6.

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