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US5149453A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for detecting leakage in a refrigeration system

Assignee: Spectronics Corp
•
Filing: 1991-03-12
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Granted: 1992-09-22
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Expires: 2011-03-12
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Abstract

Abstract A leak detectable refrigeration composition comprising an effective amount of a fluorescent, alkyl substituted perylene dye dissolved in a refrigeration oil and a polyhalogenated hydrocarbon refrigerant, is prepared for use in refrigeration systems in automobile air conditioning systems, commercial refrigeration systems, and the like. Upon exposure to ultraviolet light, there is sufficient fluorescence by the refrigeration liquid to allow one to visually detect a leak in the system due to the presence of the dye at the source of the leak. Small leaks which were previously nondetectable with dye coloring systems detectable in normal light may now be detected due to the greater visibility of the fluorescent dye under an ultraviolet light.

Inventors

  • 👤 Manher Parekh

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 21:32
CPC Classifications
C; C09; C09K; C09K5/00; C09K5/02; C09K5/04; C09K5/041; C09K5/044; C09K5/045; C09K2205/00; C09K2205/10; C09K2205/12; C09K2205/122; Y; Y10; Y10S; Y10S252/00; Y10S252/964

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 107 words
A method of detecting a leak in a refrigeration system, the method comprising: (a) circulating in a refrigeration system a composition that fluoresces under ultraviolet light comprising: (i) a refrigeration liquid comprising a polyhalogenated hydrocarbon refrigerant and a refrigeration oil; and (ii) an effective amount of a fluorescent, alkyl substituted perylene dye compound; wherein the fluorescent dye is soluble in the refrigeration liquid and does not adversely affect the operation of a refrigeration system; and (b) exposing the refrigeration system to ultraviolet light to fluoresce any of the fluorescent composition on the exterior of the refrigeration system; wherein a leak in the refrigeration system may be detected.
Claim 2
Independent Claim 107 words
A method of detecting a leak in a refrigeration system, the method comprising: (a) circulating in a refrigeration system a composition that fluoresces under ultraviolet light comprising: (i) a refrigeration liquid comprising a polyhalogenated hydrocarbon refrigerant and a refrigeration oil; and (ii) an effective amount of a fluorescent, alkyl substituted perylene dye compound; wherein the fluorescent dye is soluble in the refrigeration liquid and does not adversely affect the operation of a refrigeration system; and (b) exposing the refrigeration system to ultraviolet light to fluoresce any of the fluorescent composition on the exterior of the refrigeration system; wherein a leak in the refrigeration system may be detected.
Claim 3
Dependent Claim 13 words
The method of claim 1 wherein the refrigeration oil comprises a paraffinic oil.
Claim 4
Dependent Claim 17 words
The method of claim 1 wherein the perylene compound comprises dinaphthoperylene-9,18-dione, dodecyl derivative, having the structure: ##STR2##
Claim 5
Dependent Claim 22 words
The method of claim 1 wherein the refrigeration liquid comprises about 3 to 100 grams of refrigerant per gram of refrigeration oil.
Claim 6
Dependent Claim 26 words
The method of claim 1 further comprising introducing into the refrigerant of a refrigeration system a solution of the fluorescent dye compound in the refrigeration oil.
Claim 7
Independent Claim 115 words
A method of detecting a leak in a refrigeration system, the method comprising: (a) introducing into a refrigeration system a composition that fluoresces under ultraviolet light comprising: (i) a refrigeration liquid comprising a polyhalogenated hydrocarbon refrigerant and a refrigeration oil; and (ii) an effective amount of a fluorescent, alkyl substituted perylene dye compound; wherein the fluorescent dye is soluble in the refrigeration liquid and does not adversely affect the operation of a refrigeration system; (b) circulating the composition through the refrigeration system; and (c) exposing the refrigeration system to ultraviolet light to fluoresce any of the fluorescent composition on the exterior of the refrigeration system; wherein a leak in the refrigeration system may be detected.
Claim 8
Independent Claim 115 words
A method of detecting a leak in a refrigeration system, the method comprising: (a) introducing into a refrigeration system a composition that fluoresces under ultraviolet light comprising: (i) a refrigeration liquid comprising a polyhalogenated hydrocarbon refrigerant and a refrigeration oil; and (ii) an effective amount of a fluorescent, alkyl substituted perylene dye compound; wherein the fluorescent dye is soluble in the refrigeration liquid and does not adversely affect the operation of a refrigeration system; (b) circulating the composition through the refrigeration system; and (c) exposing the refrigeration system to ultraviolet light to fluoresce any of the fluorescent composition on the exterior of the refrigeration system; wherein a leak in the refrigeration system may be detected.
Claim 9
Dependent Claim 13 words
The method of claim 6 wherein the refrigeration oil comprises a paraffinic oil.
Claim 10
Dependent Claim 17 words
The method of claim 6 wherein the perylene compound comprises dinaphthoperylene-9,18-dione, dodecyl derivative, having the structure: ##STR3##
Claim 11
Independent Claim 128 words
A method of detecting a leak in a refrigeration system, the method comprising: (a) introducing into a refrigeration liquid of a refrigeration system, which liquid comprises a polyhalogenated hydrocarbon refrigerant and a refrigeration oil, a composition that fluoresces under ultraviolet light comprising: (i) a refrigeration oil; and (ii) an effective amount of a fluorescent, alkyl substituted perylene dye compound; wherein the fluorescent dye is soluble in the oil and the refrigeration liquid and does not adversely affect the operation of a refrigeration system; (b) circulating the refrigeration liquid and fluorescent composition through the refrigeration system; and (c) exposing the refrigeration system to ultraviolet light to fluoresce any of the fluorescent composition on the exterior of the refrigeration system; wherein a leak in the refrigeration system may be detected.
Claim 12
Independent Claim 128 words
A method of detecting a leak in a refrigeration system, the method comprising: (a) introducing into a refrigeration liquid of a refrigeration system, which liquid comprises a polyhalogenated hydrocarbon refrigerant and a refrigeration oil, a composition that fluoresces under ultraviolet light comprising: (i) a refrigeration oil; and (ii) an effective amount of a fluorescent, alkyl substituted perylene dye compound; wherein the fluorescent dye is soluble in the oil and the refrigeration liquid and does not adversely affect the operation of a refrigeration system; (b) circulating the refrigeration liquid and fluorescent composition through the refrigeration system; and (c) exposing the refrigeration system to ultraviolet light to fluoresce any of the fluorescent composition on the exterior of the refrigeration system; wherein a leak in the refrigeration system may be detected.
Claim 13
Dependent Claim 13 words
The method of claim 9 wherein the refrigeration oil comprises a paraffinic oil.
Claim 14
Dependent Claim 17 words
The method of claim 9 wherein the perylene compound comprises dinaphthoperylene-9,18-dione, dodecyl derivative, having the structure: ##STR4##

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) 1995-09-22 1996-03-23 1996-09-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-09-22 2000-03-23 2000-09-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-09-22 2004-03-23 2004-09-22 $7700.00 Window Closed / Lapsed

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