US4797376A
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Sol-gel method for making gradient-index glass
Assignee: University of Rochester
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Filing: 1987-06-09
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Granted: 1989-01-10
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Expires: 2007-06-09
Abstract
Abstract A sol-gel method for making gradient-index glass and a novel composition therefor, comprising at least a ternary system of metal alkoxides.
Inventors
- 👤 J. Brian Caldwell
- 👤 Duncan T. Moore
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 04:26
CPC Classifications
C; C03; C03C; C03C1/00; C03C1/006; C03B; C03B37/00; C03B37/01; C03B37/012; C03B37/014; C03B37/016; C03B2201/00; C03B2201/06; C03B2201/08; C03B2201/10; C03B2201/30; C03B2201/32; C03B2201/40; C03B2201/42; Y; Y10; Y10S; Y10S65/00; Y10S65/901
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
194 words
A method for making a gradient-index glass comprising the steps of (1) forming a mixture between a silicon alkoxide and an alcohol in a slightly acidic water solution sufficient to partially hydrolyze the alkoxide, (2) adding to said mixture an index modifying metal alkoxide selected from the group consisting of alkoxides of titanium and zirconium, (3) adding to said mixture at least one additional metal alkoxide element for providing an index modifying oxide wherein said metal alkoxide element is selected from the group consisting of alkoxides of aluminum, boron and germanium, (4) stirring the resulting solution with additional water sufficient to cause gelation by conversion of the metal alkoxides in solution to an interconnected network of the corresponding metal oxides, (5) pouring said solution into a mold, (6) allowing sufficient time for said solution to form a gel, (7) placing said gel into an acidic leaching bath for a time sufficient to leach out some of the index modifying metal oxide, (8) fixing said gel in an alcoholic bath, (9) drying said gel for a time sufficient to remove liquid within the gel, and (10) sintering said dried gel into transparent gradient index glass.
Claim 2
Independent Claim
194 words
A method for making a gradient-index glass comprising the steps of (1) forming a mixture between a silicon alkoxide and an alcohol in a slightly acidic water solution sufficient to partially hydrolyze the alkoxide, (2) adding to said mixture an index modifying metal alkoxide selected from the group consisting of alkoxides of titanium and zirconium, (3) adding to said mixture at least one additional metal alkoxide element for providing an index modifying oxide wherein said metal alkoxide element is selected from the group consisting of alkoxides of aluminum, boron and germanium, (4) stirring the resulting solution with additional water sufficient to cause gelation by conversion of the metal alkoxides in solution to an interconnected network of the corresponding metal oxides, (5) pouring said solution into a mold, (6) allowing sufficient time for said solution to form a gel, (7) placing said gel into an acidic leaching bath for a time sufficient to leach out some of the index modifying metal oxide, (8) fixing said gel in an alcoholic bath, (9) drying said gel for a time sufficient to remove liquid within the gel, and (10) sintering said dried gel into transparent gradient index glass.
Claim 3
Dependent Claim
30 words
The method according to claim 1 wherein the amount of silicon alkoxide is sufficient to yield a gradient index glass having between 60 and 98 mole percent of silicon oxide.
Claim 4
Dependent Claim
31 words
The method according to claim 1 wherein amount of index modifying alkoxide is sufficient to yield a gradient-index glass having between 0.1 and 25 mole percent of the index modifying oxide.
Claim 5
Dependent Claim
32 words
The method according to claim 1 wherein amount of additional metal alkoxide element is sufficient to yield a gradient-index glass having less than 25 mole percent of the additional metal oxide element.
Claim 6
Dependent Claim
14 words
The method according to claim 1 wherein said alcohol, in step (1) is methanol.
Claim 7
Dependent Claim
29 words
The method according to claim 1 wherein said acidic leaching bath comprises water and one or more acids selected from the group consisting of hydrochloric, sulfuric and nitric acids.
Claim 8
Dependent Claim
26 words
The method according to claim 1 wherein the alcohol in said alcoholic bath of step (9) is selected from the group consisting of methanol and ethanol.
References Cited (Backward Citations)
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