# US 2014/0194271 A1 · TUNING Tzc BY THE ANNEALING OF ULTRA LOW EXPANSION GLASS

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

- Number: US 2014/0194271 A1
- Document ID: US20140194271A1
- Status: Published application
- Kind: A1
- Application number: 14/208,568
- Filed: 2014-03-13
- Published: 2014-07-10
- Earliest claimed: 2009-08-31
- Assignees: Corning Incorporated
- Applicants: Corning Incorporated
- Inventors: Carlos Alberto Duran; Kenneth Edward Hrdina
- Web page: https://patentgrep.com/patent/US20140194271A1

## CPC

- C04B 35/14: based on silica
- C03B 25/025: {Glass sheets}
- C03B 25/08: of glass sheets
- C03C 3/06: with more than 90% silica by weight, e.g. quartz {(C03C3/045 takes precedence)}
- C03C 3/076: with 40% to 90% silica, by weight {(C03C3/045 takes precedence)}
- Y02P 40/57: Improving the yield, e-g- reduction of reject rates
- C04B: LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE {(roofing granules E04D7/005)}; CERAMICS (devitrified glass-ceramics C03C10/00); REFRACTORIES; TREATMENT OF NATURAL STONE
- C03B: MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03C: CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS

## Abstract

The disclosure describes a silica-titania glass having a selected titania content in the range of 5-20 wt % that has zero crossover temperature (Tzc) associated with the selected titania content withing this range, and the Tzc is adjustable by ±10° C. or less. The disclosure also describes a method by which the Tzc of a silica-titania glass article, for example, a mirror substrate, can be tuned to within a specification range by means of a selected final anneal that shifts Tzc of the article or substrate to the desired Tzc value. In addition, since different mirrors in a set can be specified at different values of Tzc, this process the method can be on used glass samples or pieces from a single glass boule to make parts with different Tzc values, thus reducing the number of separate boules required to fill an order.

## Claims

### Claim at position 1

-13. (canceled)

### Claim 14

A silica-titania glass having a selected titania content in the range of 5-20 wt % and a Tzc associated with the selected titania content within this silica-titania range, said Tzc being adjustable by ±10° C. or less without any adjustment to the titania content.

### Claim 15 (depends on 14)

The silica-titania glass according to claim 14, wherein said Tzc is adjustable by ±5° C. or less without any adjustment to the titania content.

### Claim 16

A silica-titania glass having a selected titania content in the range of 5-12 wt % and an adjustable Tzc associated with a titania content within this range, said Tzc being adjustable by ±10° C. or less without any adjustment to the titania content.

### Claim 17 (depends on 16)

The silica-titania glass according to claim 16, wherein said Tzc is adjustable by ±5° C. or less without any adjustment to the titania content.

### Claim 18

A silica-titania glass containing 7.5±0.3 wt % titania and an adjustable Tzc centered at 20° C.±1° C., said Tzc being adjustable by ±10° C. or less.

### Claim 19 (depends on 18)

The silica-titania glass according to claim 18, wherein said Tzc is adjustable by ±5° C. or less.

### Claim 20

A silica-titania glass containing 8.1±0.3 wt % titania and an adjustable Tzc centered at 20° C.±1° C., said Tzc being adjustable by ±10° C. or less.

### Claim 21 (depends on 20)

The silica-titania according to claim 20, wherein said Tzc is adjustable by ±5° C. or less.