Patent DE935625C successfully refreshed from Google Patents.
US3868170A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of removing entrapped gas and/or residual water from glass
Assignee: Corning Glass Works
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Filing: 1972-03-30
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Granted: 1975-02-25
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Expires: 1992-03-30
Abstract
Abstract A method of forming an article, such as a low loss optical waveguide, by applying to a starting member a layer of glass soot to form a porous body. The porous body is then placed in a controlled environment in which a predetermined desired concentration of gases is maintained. The porous body is heated below the sintering temperature of the glass to permit entrapped gas to escape therefrom and the temperature is maintained until an equilibrium is reached between the partial pressure of the entrapped gas in the porous body and the partial pressure of the same gas in said environment. Thereafter, the porous body is further heated to at least the sintering temperature of the glass to sinter the soot particles and to form a consolidated dense member which may thereafter be formed into a desired shape while within said environment.
Inventors
- 👤 Robert D Deluca
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 01:36
CPC Classifications
C; C03; C03B; C03B19/00; C03B19/06; C03B32/00; C03B37/00; C03B37/01; C03B37/012; C03B37/014; C03B37/01446; C03B37/01466; C03B37/02; C03B37/025; C03B37/027; C03B37/10; C03B37/14; C03B37/15; C03C; C03C3/00; C03C3/04; C03C3/06; C03B2201/00; C03B2201/06; C03B2201/30; C03B2201/31; C03B2201/32; C03B2201/34; C03B2201/40; C03B2201/42; C03B2205/00; C03B2205/12; C03B2205/16; C03C2201/00; C03C2201/06; C03C2201/08; C03C2201/10; C03C2201/30; C03C2201/31; C03C2201/40; C03C2201/42; C03C2203/00; C03C2203/10; C03C2203/50; C03C2203/52
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
148 words
THE METHOD OF FORMING AN ARTICLE COMPRISING THE STEPS OF PROVIDING A SUITABLE STARTING MEMBER, FORMING GLASS SOOT BY FLAME HYDROLYSIS, DEPOSITING A QUANTITY OF SAID GLASS SOOT ON SAID STARTING MEMBER TO FORM A POROUS BODY THEREOF, DISPOSING SAID POROUS BODY IN A CONTROLLED ENVIRONMENT, MAINTAINING A PREDETERMINED DESIRED CONCENTRATION OF GASES IN SAID ENVIRONMENT, HEATING SAID POROUS BODY TO A TEMPERATURE BELOW THE SINTERING TEMPERATURE OF SAID GLASS TO PERMIT ENTRAPPED GAS TO ESCAPE THEREFROM, MAINTAINING SAID TEMPERATURE UNTIL AN EQUILIBRIUM IS REACHED BETWEEN THE PARTIAL PRESSURE OF THE ENTRAPPED GAS IN SAID BODY AND THE PARTIAL PRESSURE OF THE SAME GAS IN SAID ENVIRONMENT, THEREAFTER HEATING SAID POROUS BODY TO AT LEAST THE SINTERING TEMPERATURE OF SAID GLASS TO SINTER SAID SOOT PARTICLES AND FORM A CONSOLIDATED DENSE MEMBER, FORMING SAID MEMBER TO A DESIRED SHAPE, AND REMOVING THE ARTICLE SO FORMED FROM SAID ENVIRONMENT.
Claim 2
Independent Claim
148 words
THE METHOD OF FORMING AN ARTICLE COMPRISING THE STEPS OF PROVIDING A SUITABLE STARTING MEMBER, FORMING GLASS SOOT BY FLAME HYDROLYSIS, DEPOSITING A QUANTITY OF SAID GLASS SOOT ON SAID STARTING MEMBER TO FORM A POROUS BODY THEREOF, DISPOSING SAID POROUS BODY IN A CONTROLLED ENVIRONMENT, MAINTAINING A PREDETERMINED DESIRED CONCENTRATION OF GASES IN SAID ENVIRONMENT, HEATING SAID POROUS BODY TO A TEMPERATURE BELOW THE SINTERING TEMPERATURE OF SAID GLASS TO PERMIT ENTRAPPED GAS TO ESCAPE THEREFROM, MAINTAINING SAID TEMPERATURE UNTIL AN EQUILIBRIUM IS REACHED BETWEEN THE PARTIAL PRESSURE OF THE ENTRAPPED GAS IN SAID BODY AND THE PARTIAL PRESSURE OF THE SAME GAS IN SAID ENVIRONMENT, THEREAFTER HEATING SAID POROUS BODY TO AT LEAST THE SINTERING TEMPERATURE OF SAID GLASS TO SINTER SAID SOOT PARTICLES AND FORM A CONSOLIDATED DENSE MEMBER, FORMING SAID MEMBER TO A DESIRED SHAPE, AND REMOVING THE ARTICLE SO FORMED FROM SAID ENVIRONMENT.
Claim 3
Dependent Claim
25 words
The method of claim 1 further comprising the step of removing said starting member before the step of forming said member to a desired shape.
Claim 4
Dependent Claim
20 words
The method of claim 1 wherein said controlled environment contains less than about 20 parts per million of water vapor.
Claim 5
Dependent Claim
41 words
The method of claim 1 wherein said glass soot is fused silica doped with at least one material selected from the group consisting of titanium oxide, tantalum oxide, tin oxide, niobium oxide, zirconium oxide, aluminum oxide, lanthanum oxide, and germanium oxide.
Claim 6
Dependent Claim
22 words
The method of claim 4 wherein said soot is fused silica doped with not more than 15 percent by weight titanium oxide.
Claim 7
Dependent Claim
20 words
The method of claim 5 wherein said article so formed contains less than 20 parts per million of residual water.
Claim 8
Dependent Claim
17 words
The method of claim 5 wherein said porous body is heated to a temperature of about 1,200*C.
Claim 9
Dependent Claim
18 words
The method of claim 7 wherein said temperature is maintained for a period of at least 24 hours.
Claim 10
Dependent Claim
48 words
The method of claim 1 further comprising the steps of applying a coating of glass soot having an index of refraction less than that of the glass of said porous body over the outside peripheral surface of said porous body before it is disposed within said controlled environment.
Claim 11
Dependent Claim
20 words
The method of claim 9 wherein said controlled environment contains less than about 20 parts per million of water vapor.
Claim 12
Dependent Claim
16 words
The method of claim 9 wherein said coating of glass soot is applied by flame hydrolysis.
Claim 13
Dependent Claim
34 words
The method of claim 11 wherein said porous body is formed of doped fused silica and said coating is formed of fused silica doped to a lesser degree than that of said porous body.
Claim 14
Dependent Claim
41 words
The method of claim 12 wherein said porous body is fused silica doped with at least one material selected from the group consisting of titanium oxide, tantalum oxide, tin oxide, niobium oxide, zirconium oxide, aluminum oxide, lanthanum oxide, and germanium oxide.
Claim 15
Dependent Claim
26 words
The method of claim 13 wherein said porous body is formed of fused silica doped with not more than 15 percent by weight of titanium oxide.
Claim 16
Dependent Claim
15 words
The method of claim 14 wherein said porous body and said coating are sintered simultaneously.
Claim 17
Dependent Claim
20 words
The method of claim 15 wherein said article so formed contains less than 20 parts per million of residual water.
Claim 18
Dependent Claim
21 words
The method of claim 1 further comprising the step of applying a coating a glass soot over the consolidated dense member.
Claim 19
Dependent Claim
115 words
The method of claim 17 further comprising the steps of disposing the structure so formed in a controlled environment, maintaining a predetermined desired concentration of gases in said environment, heating Said structure to a temperature below the sintering temperature of the glass thereof to permit entrapped gas to escape from said porous coating, maintaing said temperature until an equilibrium is reached between the partial pressure of the entrapped gas within said porous coating and the partial pressure of the same gas in said environment, and heating said structure to at least the sintering temperature of the glass of said soot to sinter said soot particles and form a consolidated dense coating over said consolidated member.
Claim 20
Dependent Claim
20 words
The method of claim 18 wherein said controlled environment contains less than about 20 parts per million of water vapor.
Claim 21
Dependent Claim
14 words
The method of claim 18 further comprising the step of removing said starting member.
Claim 22
Dependent Claim
78 words
The method of claim 20 wherein said forming said member comprises the steps of heating the structure so formed to the drawing temperature of the materials thereof, and drawing the heated structure to reduce the cross sectional area thereof and to collapse the hole resulting from removing said starting member and to form a clad fiber having a solid cross-section, the collapsed consolidated dense member forming the core of said fiber and said coating forming the fiber cladding.
Claim 23
Dependent Claim
13 words
The method of claim 21 wherein said drawing is performed within said environment.
Claim 24
Dependent Claim
20 words
The method of claim 22 wherein said article so formed contains less than 20 parts per million of residual water.
Claim 25
Dependent Claim
9 words
An article formed by the method of claim 1.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-02-24 | 1978-08-26 | 1979-02-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-24 | 1982-08-26 | 1983-02-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-24 | 1986-08-26 | 1987-02-25 | $7700.00 | Window Closed / Lapsed |