# US 8,539,795 B2 · Methods for cutting a fragile material

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 8,539,795 B2
- Document ID: US8539795B2
- Status: Granted
- Kind: B2
- Application number: 13/319,200
- Filed: 2010-05-13
- Published: 2012-03-01
- Granted: 2013-09-24
- Earliest claimed: 2010-05-13
- Assignees: Corning Incorporated
- Applicants: Thierry Luc Alain Dannoux; Philippe Lehuede
- Inventors: Thierry Luc Alain Dannoux; Philippe Lehuede
- Web page: https://patentgrep.com/patent/US8539795B2

## CPC

- C03B 33/091: {using at least one focussed radiation beam, e.g. laser beam (C03B33/0955 takes precedence)}
- B23K 26/40: taking account of the properties of the material involved
- C03B 33/093: {using two or more focussed radiation beams}
- B23K 2103/50: {Inorganic materials other than metals or composite materials}
- C03B: MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- B23K: SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM

## Abstract

Methods for cutting a fragile material are provided. The methods comprise the step of heating the fragile material along a separation path to separate the fragile material into a first portion and a second portion. At least the first portion includes a first thermal affected zone extending along the separation path. The methods further include the steps of spontaneously splitting at least part of the first thermal affected zone from the remainder of the first portion along a first split path extending a first distance from the separation path. The spontaneous splitting occurs as a consequence of the step of heating the fragile material.

## Claims

### Claim 1

A method for cutting a fragile material (10) comprising the steps of:
separating the fragile material along a separation path (12) into a first portion (14a) and second portion (14b) by heating the fragile material with a laser (50) along the separation path (12), wherein at least the first portion (14a) is separated from the second portion (14b) with the first portion (14a) including a first thermal affected zone (16a) extending along the separation path; and then
subsequently splitting at least part of the first thermal affected zone from the remainder of the first portion along a first split path (18a) extending a first distance (L1) laterally spaced from the separation path, wherein the subsequent splitting occurs as a consequence of heating the fragile material during the step of separating.

### Claim 2 (depends on 1)

The method of claim 1, wherein the step of splitting provides the first portion (14a) with a first clean edge (22a) extending along the first split path (18a).

### Claim 3 (depends on 1)

The method of claim 1, wherein heating during the step of separating is configured to provide internal stresses within the first portion (14a) sufficient to result in the step of splitting.

### Claim 4 (depends on 1)

The method of claim 1, wherein the step of splitting includes propagating a first crack along the first split path (18a).

### Claim 5 (depends on 1)

The method of claim 1, wherein the first distance (L1) is substantially constant along the separation path (12).

### Claim 6 (depends on 1)

The method of claim 1, wherein the second portion (14b) includes a second thermal affected zone (16b) extending along the separation path (12).

### Claim 7 (depends on 6)

The method of claim 6, further comprising the step of subsequently splitting at least part of the second thermal affected zone (16b) from the remainder of the second portion (14b) along a second split path (18b) extending a second distance (L2) laterally spaced from the separation path (12) after the step of heating, wherein the subsequent splitting of at least part of the second thermal affected zone (16b) occurs as a consequence of heating the fragile material (10) during the step of separating.

### Claim 8 (depends on 7)

The method of claim 7, wherein the first distance (L1) is substantially equal to the second distance (L2).

### Claim 9 (depends on 1)

The method of claim 1, wherein a thickness of the fragile material (10) is equal to or less than 150 μm.

### Claim 10 (depends on 1)

The method of claim 1, wherein the fragile material (10) comprises a glass material.

### Claim 11 (depends on 10)

The method of claim 10, wherein a coefficient of thermal expansion of the glass material is from 10 to 70×10−7/K between 25-300° C.

### Claim 12 (depends on 1)

The method of claim 1, wherein the laser (50) emits a wavelength between 10 μm and 11 μm.

### Claim 13 (depends on 1)

The method of claim 1, wherein the laser (50) has a power from about 50 W to about 150 W during the step of heating.

### Claim 14 (depends on 1)

The method of claim 1, wherein the step of heating is modified to accommodate changes in thickness of the fragile material (10).

### Claim 15 (depends on 1)

The method of claim 1, wherein the fragile material (10) is heated at a speed from about 20 mm/s to about 60 mm/s along a direction of the separation path (12).

### Claim 16 (depends on 1)

The method of claim 1, where the first split path (18a) is substantially parallel to the separation path (12).

### Claim 17 (depends on 7)

The method of claim 7, where the second split path (18b) is substantially parallel to the separation path (12).