US4249412A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluorescent leak detection composition
Assignee: Individual
•
Filing: 1978-12-11
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Granted: 1981-02-10
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Expires: 1998-12-11
Abstract
Abstract A fluorescent leak detection composition is provided comprising water, a nonionic surfactant having an HLB value of about 12 to about 14 in an amount effective to produce stable bubbling of the composition for a time sufficient to enable detection of a leak in a container when the composition is applied to the surface thereof, about 0.025 to about 1.0 weight percent sodium fluorescein and a semisynthetic cellulose thickening agent in an amount effective to provide the composition with a viscosity of about 75 to about 125 cps at 20° C. Preferably, an antifreeze agent is added in an amount effective to retard freezing of the composition for at least 5 minutes when the composition is applied to a cold surface, such as refrigeration pipes.
Inventors
- 👤 Claude A. Townsend, III
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:07
CPC Classifications
G; G01; G01M; G01M3/00; G01M3/02; G01M3/04; G01M3/12
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
144 words
A method of detecting a leak in a container comprising applying a thick coating to the exterior surface of the container of an aqueous fluorescent leak detection composition comprising water, a nonionic surfactant having an HLB value of about 12 to about 14 in an amount effective to promote wetting and bubbling of the composition for a time sufficient to detect a leak in the container, about 0.025 to about 1.0 weight percent sodium fluorescein, a semisynthetic cellulose thickening agent in an amount effective to provide the composition with a viscosity of about 75 to about 125 cps at 20° C., and an antifreeze agent in an amount effective to retard freezing of the composition for a sufficient time to detect a leak when the composition is applied to a cold surface, and detecting bubbling of the composition in the presence of a leak.
Claim 2
Independent Claim
144 words
A method of detecting a leak in a container comprising applying a thick coating to the exterior surface of the container of an aqueous fluorescent leak detection composition comprising water, a nonionic surfactant having an HLB value of about 12 to about 14 in an amount effective to promote wetting and bubbling of the composition for a time sufficient to detect a leak in the container, about 0.025 to about 1.0 weight percent sodium fluorescein, a semisynthetic cellulose thickening agent in an amount effective to provide the composition with a viscosity of about 75 to about 125 cps at 20° C., and an antifreeze agent in an amount effective to retard freezing of the composition for a sufficient time to detect a leak when the composition is applied to a cold surface, and detecting bubbling of the composition in the presence of a leak.
Claim 3
Dependent Claim
119 words
An aqueous fluorescent leak detection composition comprising water, a nonionic surfactant having an HLB value of about 12 to about 14 in an amount effective to promote wetting and bubbling of the composition for a time sufficient to detect a leak in a container when the composition is applied to the surface thereof, about 0.025 to about 1.0 weight percent sodium fluorescein, a semisynthetic cellulose thickening agent in an amount effective to provide the composition with a viscosity of about 75 to about 125 cps at 20° C., and an antifreeze agent in an amount effective to retard freezing of the composition for a sufficient time to detect a leak when the composition is applied to a cold surface.
Claim 4
Dependent Claim
119 words
An aqueous fluorescent leak detection composition comprising water, a nonionic surfactant having an HLB value of about 12 to about 14 in an amount effective to promote wetting and bubbling of the composition for a time sufficient to detect a leak in a container when the composition is applied to the surface thereof, about 0.025 to about 1.0 weight percent sodium fluorescein, a semisynthetic cellulose thickening agent in an amount effective to provide the composition with a viscosity of about 75 to about 125 cps at 20° C., and an antifreeze agent in an amount effective to retard freezing of the composition for a sufficient time to detect a leak when the composition is applied to a cold surface.
Claim 5
Dependent Claim
35 words
A composition according to claim 1 wherein the surfactant is selected from the group consisting of polyoxyethylene sorbitol monolaurate, polyoxyethylene sorbitol oleate-laurate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monooleate, dodecylbenzenesulfonic acid type surfactant and mixtures thereof.
Claim 6
Dependent Claim
24 words
A composition according to claim 1 wherein the antifreeze agent is ethylene glycol present in an amount of about 10 to 20 weight percent.
Claim 7
Dependent Claim
24 words
A composition according to claim 1 wherein the thickening agent is selected from the group consisting of carboxymethylcellulose, hydroxymethylcellulose, methylcellulose, ethylcellulose and mixtures thereof.
Claim 8
Dependent Claim
21 words
A composition according to claim 1 wherein the thickening agent is carboxymethylcellulose present in an amount of about 1 weight percent.
Claim 9
Dependent Claim
30 words
A composition according to claim 1 which is sufficiently transparent as applied to a surface to allow any holes or cracks in the surface to be visible through the composition.
Claim 10
Dependent Claim
47 words
An aqueous fluorescent leak detection composition comprising water, about 10 weight percent of a nonionic dodecylbenzenesulfonic acid type surfactant having an HLB value of about 12 to about 14, about 0.25 weight percent sodium fluorescein, about 1 weight percent carboxymethylcellulose and about 10 weight percent ethylene glycol.
Claim 11
Dependent Claim
47 words
An aqueous fluorescent leak detection composition comprising water, about 10 weight percent of a nonionic dodecylbenzenesulfonic acid type surfactant having an HLB value of about 12 to about 14, about 0.25 weight percent sodium fluorescein, about 1 weight percent carboxymethylcellulose and about 10 weight percent ethylene glycol.
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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) | 1984-02-10 | 1984-08-11 | 1985-02-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-02-10 | 1988-08-11 | 1989-02-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-02-10 | 1992-08-11 | 1993-02-10 | $7700.00 | Window Closed / Lapsed |