(19) United States US 20080135817A1

(12) Patent Application Publication (10) Pub. No.: US 2008/0135817 A1 Luly et al. (43) Pub. Date: Jun. 12, 2008

(54) GASEOUS DIELECTRICS WITH LOW GLOBAL WARMING POTENTIALS

(75) Inventors: Matthew H. Luly, Hamburg, NY (US); Robert G. Richard, Hamburg, NY (US)

Correspondence Address: Honeywell International Inc. Patent Services Department 101 Columbia Road Morristown, NJ 07962

(73) Assignee: Honeywell International Inc.

(21) Appl. No.: 11/637,657

(22) Filed: Dec. 12, 2006

Publication Classification

(51) Int. Cl. HOIB 3/20 (2006.01)

(52) U.S. Cl. ........................................................ 252/571

(57) ABSTRACT

A dielectric gaseous compound which exhibits the following properties: a boiling point in the range between about -20° C. to about -273°C.; non-ozone depleting; a GWP less than about 22,200; chemical stability, as measured by a negative standard enthalpy of formation (dElf<0); a toxicity level such that when the dielectric gas leaks, the effective diluted con centration does not exceed its PEL; and a dielectric strength greater than air.

US 2008/O 135817 A1

GASEOUS DELECTRICS WITH LOW GLOBAL WARMING POTENTIALS

1. FIELD

0001. The present disclosure relates generally to a class of gaseous dielectric compounds having low global warming potentials (GWP). In particular, such gaseous dielectric com pounds exhibits the following properties: a boiling point in the range between about -20°C. to about -273° C.; low, preferably non-ozone depleting; a GWP less than about 22,200; chemical stability, as measured by a negative stan dard enthalpy of formation (dHf<0); a toxicity level such that when the dielectric gas leaks, the effective diluted concentra tion does not exceed its PEL, e.g., a PEL greater than about 0.3 ppm by Volume (i.e., an Occupational Exposure Limit (OEL or TLV) of greater than about 0.3 ppm); and a dielectric strength greater than air. These gaseous dielectric compounds are particularly useful as insulating-gases for use with elec trical equipment, such as gas-insulated circuit breakers and current-interruption equipment, gas-insulated transmission lines, gas-insulated transformers, or gas-insulated Substa tions.

2. BACKGROUND

0002 Sulfur hexafluoride (SF) has been used as a gas eous dielectric (insulator) in high Voltage equipment since the 1950s. It is now known that SF6 is a potent greenhouse Warming gas with one of the highest global Warming poten tials (GWP) known. Because of its high GWP, it is being phased out of all frivolous applications. However, there is currently no known Substitute for SF in high Voltage equip ment. The electrical industry has taken steps to reduce the leak rates of equipment, monitor usage, increase recycling, and reduce emissions to the atmosphere. However, it would still be advantageous to find a substitute for SF in electrical dielectric applications. 0003. The basic physical and chemical properties of SF,

its behavior in various types of gas discharges, and its uses by the electric power industry have been broadly investigated. 0004. In its normal state, SF is chemically inert, non toxic, non-flammable, non-explosive, and thermally stable (it does not decompose in the gas phase attemperatures less than 500° C.). SF exhibits many properties that make it suitable for equipment utilized in the transmission and distribution of electric power. It is a strong electronegative (electron attach ing) gas both at room temperature and at temperatures well above ambient, which principally accounts for its high dielec tric strength and good arc-interruption properties. The break down Voltage of SF is nearly three times higher than air at atmospheric pressure. Furthermore, it has good heat transfer properties and it readily reforms itself when dissociated under high gas-pressure conditions in an electrical discharge or an arc (i.e., it has a fast recovery and it is self-healing). Most of its stable decomposition byproducts do not significantly degrade its dielectric strength and are removable by filtering. It produces no polymerization, carbon, or other conductive deposits during arcing, and its is chemically compatible with most Solid insulating and conducting materials used in elec trical equipment attemperatures up to about 200° C. 0005 Besides it good insulating and heat transfer proper

ties, SF has a relatively high pressure when contained at room temperature. The pressure required to liquefy SF at 21° C. is about 2100 kPa; its boiling point is reasonably low,

Jun. 12, 2008

–63.8°C., which allows pressures of 400 kPa to 600 kPa (4 to 6 atmospheres) to be employed in SF-insulated equip ment. It is easily liquefied underpressure at room temperature allowing for compact storage in gas cylinders. It presents no handling problems, is readily available, and reasonably inex pensive. 0006 SF replaced air as a dielectric in gas insulated equipment based on characteristics such as insulation ability, boiling point, compressibility, chemical stability and non toxicity. They have found that pure SF, or SF-nitrogen mixtures are the best gases to date. 0007. However, SF has some undesirable properties: it can form highly toxic and corrosive compounds when Sub jected to electrical discharges (e.g., SF SOF); non-polar contaminants (e.g., air, CF) are not easily removed from it: its breakdown Voltage is sensitive to water vapor, conducting particles, and conductor Surface roughness; and it exhibits non-ideal gas behavior at the lowest temperatures that can be encountered in the environment, i.e., in cold climatic condi tions (about -50° C.). SF becomes partially liquefied at normal operating pressures (400 kPa to 500 kPa). SF is also an efficient infrared (IR) absorber and due to its chemical inertness, is not rapidly removed from the earth's atmosphere. Both of these latter properties make SF a potent greenhouse gas, although due to its chemical inertness (and the absence of chlorine and bromine atoms in the SF molecule) it is benign with regard to stratospheric ozone depletion. 0008 That is, greenhouse gases are atmospheric gases which absorb a portion of the infrared radiation emitted by the earth and return it to earth by emitting it back. Potent green house gases have strong infrared absorption in the wavelength range from approximately 7 um to 13 Jum. They occur both naturally in the environment (e.g., H2O, CO., CH, NO)and as man-made gases that may be released (e.g., SF, perfluori nated compound (PFC); combustion products such as CO, nitrogen, and Sulfur oxides). The effective trapping of long wavelength infrared radiation from the earth by the naturally occurring greenhouse gases, and its reradiation back to earth, results in an increase of the average temperature of the earth's Surface. Mans impact on climate change is an environmental issue that has prompted the implementation of the Kyoto Protocol regulating the emissions of man made greenhouse gases in a number of countries. 0009 SF is an efficient absorber of infrared radiation, particularly at wavelengths near 10.5 Lum. Additionally, unlike most other naturally occurring greenhouse gases (e.g., CO, CH). SF is only slowly decomposed; therefore its contribution to global warming is expected to be cumulative and long lasting. The strong infrared absorption of SF and its long lifetime in the environment are the reasons for its extremely high global warming potential which for a 100 year time horizon is estimated to be approximately 22.200 times greater (per unit mass) than that of CO, the predomi nant contributor to the greenhouse effect. The concern about the presence of SF in the environment derives exclusively from this very high value of its potency as a greenhouse gas. 0010. Accordingly, many in the electrical equipment industry have spent Substantial time and effort seeking Suit able replacement gases to reduce the use of SF in high Volt age electrical equipment. To date, the possible replacement gases have been identified as (i) mixtures of SF and nitrogen for which a large amount of research results are available; (ii) gases and mixtures (e.g., pure nitrogen, low concentrations of SF in N, and SF. He mixtures) for which a smaller yet

US 2008/O 135817 A1

significant amount of data is available; and (iii) potential gases for which little experimental data is available. 0011. Some replacements which have been proposed have higher GWPs than SF. For example, CFSF's falls into this category. Because of fugitive emissions in the manufacture, transportation, filling and use of Such chemicals, they should be avoided.

0012 However, the present inventors have determined that given the environmental difficulty of SF, it is necessary to relax certain of the requirements traditionally held as impor tant and accept as an alternative gas, compromise candidates with a lower GWP. For example, gases which are non-toxic are often inert with long atmospheric lifetimes which can yield high GWP. By accepting a somewhat more reactive gas than SF, the GWP can be greatly reduced. It may also be necessary to accept slightly more toxic materials in order to find the best alternative in these applications. Such an increase intoxicity can be offset by reducing equipment leak rates or installing monitoring equipment. In some cases, the gases discovered by the present inventors as Suitable alterna tives to SF are show to be efficient at low levels and can be mixed with nitrogen and/or another non-toxic gas to give dielectrics with greatly reduced toxicity and acceptably low GWPS.

0013 The unique gaseous compounds discovered by the present inventors for use as substitutes for SF can be used in Some existing electrical equipment, although they would preferably be used in specific electrical equipment optimized for them. The gaseous compounds of the present disclosure are preferably used in pure form, but can also be used as part of an azeotrope, or a mixture with an appropriate second gas, such as nitrogen, CO or NO.

SUMMARY

0014. A dielectric gaseous compound which exhibits the following properties: a boiling point in the range between about -20°C. to about -273°C.; low, preferably non-ozone depleting; a GWP less than about 22,200; chemical stability, as measured by a negative standard enthalpy of formation (dHf<0); a toxicity level such that when the dielectric gas leaks, the effective diluted concentration does not exceed its PEL (i.e., an Occupational Exposure Limit (OEL or TLV) of at least about 0.3 ppm); and a dielectric strength greater than a1.

0015 The dielectric gaseous compound is at least one compound selected from the group consisting of

Arsenic pentafluoride

Arsine

Diboron tetrafluoride

Diborane

Perchloric acid, 2-chloro-1,1,2,2-tetrafluoroethyl ester (9CI)

Perchloric acid, 1.2.2-trichloro-1,2-difluoroethyl ester

Trifluoroacetyl chloride

0016 trifluoromethylisocyanide (CF3-NC) trifluoromethyl isocyanide

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trifluoro-nitroso-ethene?/Trifluor-nitroso-aethen

Tetrafluoroethene

0017 3,3,4,4-tetrafluoro-3,4-dihydro-1,2diazete

(Difluoramino)difluoracetonitril Tetrafluorooxirane

Trifluoroacetyl fluoride Perfluorimethylfluorformiat 0018 trifluoro-acetyl hypofluorite perfluoro-2-aza-1-propene

Perfluor-2-aza-1-propen (germ.)

N-Fluor-tetrafluor-1-aethanimin (germ.) 0019. 3.3-difluoro-2-trifluoromethyl-oxaziridine bis-trifluoromethyl-diazene/hexafluoro-icis-azomethane

Fluoroxypentafluoroethane

(0020 bis-trifluoromethyl peroxide

1,1-Bis(fluoroxy)tetrafluoroaethan

Hexafluorodimethyl sulfide

0021 3-fluoro-3#H!-diazirine-3-carbonitrile

Ethyne

0022 1.2.2-trifluoro-aziridine

Ketene

(0023 (difluoro)vinylboran

(Difluor)vinylboran (germ.)

0024 trifluoro-vinyl-silane

Ethinylsilan

(0025 ethyl-difluor-borane

Ethyl-difluor-boran (germ.) 0026 methyl-methylen-amine

Dimethyl ether (0027 vinyl-silane

Dimethylsilane Chloroethyne

0028 fluoroethyne/fluoro-acetylene

Ethanedinitrile

0029 tetrafluoropropyne?/1,3,3,3-tetrafluoropropyne hexafluoro-oxetane

Trifluoro(trifluoromethyl)oxirane

1,1,1,3,3,3-Hexafluoropropanone

US 2008/O 135817 A1 Jun. 12, 2008

0030 pentafluoro-propionyl fluoride?/perfluoropropionyl #Sil-bromo-it-Sil. iSi!'-methanediyl-bis-silane fluoride #Si-iodo-it-Sili Si'-methanediyl-bis-silane Trifluoromethyl trifluorovinyl ether Difluormethylnitrit

1-Propyne 0039 trifluoromethanol

Cyclopropane Formyl fluoride Propane Cyanic acid Trimethylborane Chlorine 0031 cyanoketene Chlorine fluoride butatriene

Chlorine trioxide fluoride

Cyano-bispentafluorethyl-phosphin 0040 carbon oxide selenide/Kohlenoxidselenid Trimethyl-1,1,2,2-tetrafluorethylsilan 0032 methyl diborane Fluorine

Difluorosilane Methyldiboran (germ.)

0033 carbonyl bromide fluoride chloro-difluoro-nitroso-methane?/Chlor-difluor-nitroso methan

Fluorine oxide

0041 fluorine peroxide

chloroperoxytrifluoromethane Sulfuryl fluoride carbonylchlorid-fluorid 0042 sulphur difluoride

Carbonychloridifluorid (germ.) Phosphorus trifluoride oxide 0034 33-difluoro-3HH-diazirine Phosphorus trifluoride sulfide

difl di th 1UOO C187Olea 0043 tetrafluorophosphorane

Difluordiazomethan (germ.) Tetrafluorohydrazine Carbonyl fluoride

Sulfur tetrafluoride Difluordioxiran

0044 hexafluoro disiloxane 0035 difluoro-(3-fluoro-3HH!-diazirin-3-yl)-amine trifluoromethylazide Hexafluordisiloxan (germ.)

Trifluormethylazid (germ.) Nitryl fluoride

0036 tetrafluoro-diaziridine Hydrogen Hydrogen selenide

Fluorperoxytrifluorimethan Phosphorus trihydride

Bis(fluoroxy)difluormethan Germanium hydride Trifluormethyl-phosphonylfluorid Silane

Cyanogen fluoride Tin tetrahydride

Trifluorimethylphosphane (germ.) Oxygen

Diazomethane OZone

0037 formaldehyde/Formalin (methyl)difluoroborane Antimony monophosphide

Disilicon monophosphide (Methyl)difluorboran (germ.) Radon

Chloromethane Argon

0038 methylphosphonous acid difluoride/difluoro-me thyl-phosphine Trifluoroborane trifluoro-methoxy-silane Hydrogen bromide Methylhypofluorid Bromopentafluoroethane Methane Chlorotrifluoroethene

Methylsilane Trifluoroacetonitrile

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0045 trifluoromethyl isocyanate trifluoromethyl thiocarbonyl fluoride

Trifluormethylthiocarbonylfluorid (germ.)

0046) aethan (trifluoromethyl-carbonyl)-difluoro-amine

pentafluoro-nitroso-ethane//Pentafluor-nitroso

Hexafluoroethane

Bis-trifluorimethyl-nitroxid

0047 bis-trifluoromethyl ether bis(trifluoromethyl)tellurium bis(trifluoromethyl)ditelluride

N,N-Difluor-pentafluoraethylarnin (germ.)

N-Fluor-bis(trifluorimethyl)-amin (germ.)

N-Fluor-N-trifluorimethoxy-perfluormethylamin (germ.)

0048 fluoroformyl cyanide 1-chloro-1-fluoro-ethene/71-Chlor-1-fluor-aethen//1-chloro 1-fluoroethylene

1,1-Difluoroethene

0049 it trans-1,2-difluoro-ethene/#trans-vinylene dif luoride/(E)-1,2-difluoroethylene?/(E)-1,2-difluoro-ethene/ itrans-vinylene fluoride 1,2-difluoro-ethene/icis-vinylene difluoride/1.2-Difluor aethen//vinylene fluoride icis-1,2-difluoro-ethene//icis-Vinylene difluoride//(Z)-1, 2-difluoroethylene//(Z)-1,2-difluoro-ethene/icis-Vinylene fluoride

1,1,1,2-Tetrafluoroethane

1,1,2,2-Tetrafluoroethane Fluoroethene

1,1,1-Trifluoroethane

Ether, methyl trifluoromethyl Ethene

1,1-Difluoroethane Fluoroethane

Ethane

0050 fluoro-dimethyl-borane

Disiloxane, 1,1,3,3-tetrafluoro-1,3-dimethyl-Trifluoroethene

0051 trifluoroacetaldehyde?/Trifluor-acetaldehyd

Pentafluoroethane

Difluoromethyl trifluoromethyl ether

Tris(trifluoromethyl)bismuth

0052 tetrafluoropropadiene/tetrafluoro-allene/ 1,1,3,3- tetrafluoro-1,2-propadiene

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tetrafluorocyclopropene

Perfluoropropionyliodid

0053 trile hexafluoro-cyclopropane?/Hexafluor-cyclopropan//freon HCl216

pentafluoro-propionitrile?/pentafluoropropiononi

Hexafluoropropylene

0054 hexafluoro-1,3dioxolane

Octafluoropropane Perfluormethylethylether 0055 1,1-difluoro-propadiene/allenylidene difluoride/1. 1-difluoro-allene 2,3,3,3-tetrafluoro-propene/HFO-1234yf trans. HFO-1234ze

3,3,3-Trifluoropropene 0056 cyclopropene

Allene

0057 1,1-difluoro-propene/propenylidene difluoride/1. 1-Difluor-propen methylketene 2-fluoropropene

1-Propene DL-2-aminopropanoic acid 0058 3,3,3-trifluoro-propyne/3,3,3-Trifluor-propin/trif luoromethyl-ethyne/3,3,3-trifluoro-1-propyne 1,1,3,3,3-pentafluoro-propene/1,1,3,3,3-Pentafluor-propen 1.2.3.3.3-pentafluoro-propene 1.1.1.4.4.4-hexafluoro-2-butyne 1,1,4,4-tetrafluoro-butane-2,3-dione

Trifluormethylhypochlorit Chlor-difluor-methyl-hypofluorit N-Chlor-N-fluor-trifluorimethylamin (germ.) Chlordifluordifluoraminomethan

0059 thiocarbonyl difluoride

Thiocarbonyldifluorid (germ.)

0060 selenocarbonyl difluoride

Trifluoroiodomethane

N-Fluor-difluorimethanimin (germ.) 0061 trifluoro-nitroso-methane/Trifluor-nitroso-methan difluoro-carbamoyl fluoride trifluoro-nitro-methane/Trifluor-nitro-methan//fluoropicrin

Tetrafluoromethane

Tetrafluorformamidin (germ.) 0062 tetrafluorourea hypofluorous acid trifluoromethyl ester//Hypofluorigsaeure trifluorimethylester//trifluoromethyl hypofluorite

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trifluoromethanesulfonyl fluoride

N,N-Difluor-trifluorimethylamin (germ.) Trifluormethyloxydifluoramin (Difluoraminoxy)difluorimethylhypofluorit 0063 sulfurcyanide pentafluoride

Schwefelcyanid-pentafluorid (germ.) 0064 difluoro-trifluoromethyl-phosphine

Hexafluormethandiamin

0065 perfluoro methylsilane

Perfluorimethylsilan (germ.) Trifluormethyl-tetrafluorphosphoran (germ.) Difluoromethane

Fluoroiodomethane

0066 fluoromethane/methyl fluoride/Fluor-methan// freon-41 trifluoromethyl-silane' CF3SiH3 methyltrifluorosilane difluoro-methyl-silane fluoro-methyl-silane methylgermane

Difluorformimin

Trifluoromethane

0067 trifluoromethane thiol

Trifluormethanthiol (germ.) N.N.,1,1-Tetrafluorimethylamin

0068 difluoro dichlorosilane

Difluordichlorsilan (germ.) 0069 difluoro chlorosilane

Difluorchlorsilan (germ.) Phosphorus chloride difluoride Chlorotrifluorosilane

Hydrogen chloride Chlorosilane

Carbon monoxide

Carbon dioxide

Carbonyl sulfide Difluoramine

0070 trans-Difluorodiazine cis-Difluorodiazine

Thionyl fluoride Trifluorosilane

Nitrogen trifluoride Trifluoramine oxide

(0071 thiazyl trifluoride

Phosphorus trifluoride Germanium(IV) fluoride Tetrafluorosilane

Phosphorus pentafluoride Selenium hexafluoride

Tellurium hexafluoride

0072 fluorosilane

Nitrosyl fluoride Fluorine nitrate

Hydrogen sulfide Ammonia

Helium

Hydrogen iodide Krypton Nitrogen (0073 dinitrogen oxide

Neon

Nitrogen oxide; and Xenon

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0074 More preferably, the dielectric compounds can be selected from the group consisting of:

Argon Trifluoroborane

Hydrogen bromide Bromopentafluoroethane Chlorotrifluoroethene

Trifluoroacetonitrile

(0075 trifluoromethyl isocyanate trifluoromethyl thiocarbonyl fluoride

Trifluormethylthiocarbonylfluorid (germ.) 0076 pentafluoro-nitroso-ethane/Pentafluor-nitroso aethan (trifluoromethyl-carbonyl)-difluoro-amine

Hexafluoroethane

Bis-trifluorimethyl-nitroxid (0077 bis-trifluoromethyl ether bis(trifluoromethyl)tellurium bis(trifluoromethyl)ditelluride

N,N-Difluor-pentafluoraethylamin (germ.) N-Fluor-bis(trifluorimethyl)-amin (germ.) N-Fluor-N-trifluorimethoxy-perfluormethylamin (germ.) (0078 fluoroformylcyanide

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1-chloro-1-fluoro-ethene/71-Chlor-1-fluor-aethen//1-chloro 1-fluoroethylene 1,1-Difluoroethene itrans-1,2-difluoro-ethene//#trans-vinylene difluoride/ (E)-1,2-difluoroethylene/(E)-1,2-difluoro-ethene/#trans vinylene fluoride 1,2-difluoro-ethene/icis-vinylene difluoride/1.2-Difluor aethen//vinylene fluoride icis-1,2-difluoro-ethene//icis-Vinylene difluoride//(Z)-1, 2-difluoroethylene//(Z)-1,2-difluoro-ethene/icis-Vinylene fluoride

1,1,1,2-Tetrafluoroethane 1,1,2,2-Tetrafluoroethane Fluoroethene

1,1,1-Trifluoroethane Ether, methyl trifluoromethyl Ethene

1,1-Difluoroethane Fluoroethane

Ethane

0079 fluoro-dimethyl-borane

Disiloxane, 1,1,3,3-tetrafluoro-1,3-dimethyl-Trifluoroethene 0080 trifluoroacetaldehyde?/Trifluor-acetaldehyd

Pentafluoroethane

Difluoromethyl trifluoromethyl ether Tris(trifluoromethyl)bismuth 0081 tetrafluoropropadiene/tetrafluoro-allene/ 1,1,3,3- tetrafluoro-1,2-propadiene tetrafluorocyclopropene

Perfluoropropionyliodid

0082 trile hexafluoro-cyclopropane?/Hexafluor-cyclopropan//freon HCl216

pentafluoro-propionitrile?/pentafluoropropiononi

Hexafluoropropylene

0083 hexafluoro-1,3dioxolane

Octafluoropropane Perfluormethylethylether 0084 1,1-difluoro-propadiene/allenylidene difluoride/ 1,1-difluoro-allene 2,3,3,3-tetrafluoro-propene/HFO-1234yf trans. HFO-1234ze

3,3,3-Trifluoropropene I0085 cyclopropene

Allene

I0086 1,1-difluoro-propene/propenylidene difluoride/1. 1-Difluor-propen methylketene

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2-fluoropropene

1-Propene DL-2-aminopropanoic acid I0087 3,3,3-trifluoro-propyne/3,3,3-Trifluor-propin/trif luoromethyl-ethyne/3,3,3-trifluoro-1-propyne 1,1,3,3,3-pentafluoro-propene/1,1,3,3,3-Pentafluor-propen 1.2.3.3.3-pentafluoro-propene 1.1.1.4.4.4-hexafluoro-2-butyne 1,1,4,4-tetrafluoro-butane-2,3-dione

Trifluormethylhypochlorit Chlor-difluor-methyl-hypofluorit N-Chlor-N-fluor-trifluorimethylamin (germ.) Chlordifluordifluoraminomethan

I0088 thiocarbonyl difluoride

Thiocarbonyldifluorid (germ.)

I0089 selenocarbonyl difluoride

Trifluoroiodomethane

N-Fluor-difluorimethanimin (germ.) 0090 trifluoro-nitroso-methane/Trifluor-nitroso-methan difluoro-carbamoyl fluoride trifluoro-nitro-methane/Trifluor-nitro-methan//fluoropicrin

Tetrafluoromethane

Tetrafluorformamidin (germ.) 0091 tetrafluorourea hypofluorous acid trifluoromethyl ester//Hypofluorigsaeure trifluorimethylester//trifluoromethyl hypofluorite trifluoromethanesulfonyl fluoride

N,N-Difluor-trifluorimethylamin (germ.) Trifluormethyloxydifluoramin (Difluoraminoxy)difluorimethylhypofluorit 0092 sulfurcyanide pentafluoride

Schwefelcyanid-pentafluorid (germ.) 0093 difluoro-trifluoromethyl-phosphine

Hexafluormethandiamin

(0094 perfluoro methylsilane

Perfluorimethylsilan (germ.) Trifluormethyl-tetrafluorphosphoran (germ.) Difluoromethane

Fluoroiodomethane

0.095 freon-41 trifluoromethyl-silane' CF3SiH3 methyltrifluorosilane difluoro-methyl-silane fluoro-methyl-silane

fluoromethane//methyl fluoride/Fluor-methan//

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methylgermane

Difluorformimin

Trifluoromethane

0096 trifluoromethane thiol

Trifluormethanthiol (germ.) N.N.,1,1-Tetrafluorimethylamin

0097 difluoro dichlorosilane

Difluordichlorsilan (germ.) 0098 difluoro chlorosilane

Difluorchlorsilan (germ.) Phosphorus chloride difluoride Chlorotrifluorosilane

Hydrogen chloride Chlorosilane

Carbon monoxide

Carbon dioxide

Carbonyl sulfide Difluoramine

0099 trans-Difluorodiazine cis-Difluorodiazine

Thionyl fluoride Trifluorosilane

Nitrogen trifluoride Trifluoramine oxide

0100 thiazyl trifluoride

Phosphorus trifluoride

Germanium(IV) fluoride Tetrafluorosilane

Phosphorus pentafluoride Selenium hexafluoride

Tellurium hexafluoride

0101 fluorosilane

Nitrosyl fluoride Fluorine nitrate

Hydrogen sulfide Ammonia

Helium

Hydrogen iodide Krypton Nitrogen Nitrous oxide

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Neon

Nitrogen oxide; and Xenon

0102 The dielectric gaseous compound is optionally form as an azeotrope, which imparts many advantages in handling the mixture. Preferred mixtures for dielectric gaseous com pound contain one additional gas selected from the group consisting of nitrogen, CO and N.O. 0103) The present disclosure also includes an insulation gas for use in electrical equipment, wherein said insulation gas is a dielectric gaseous compound which exhibits the fol lowing properties: a boiling point in the range between about -20° C. to about -273° C.: low, preferably non-ozone depleting; a GWP less than about 22,200; chemical stability, as measured by a negative standard enthalpy of formation (dHf<0); a toxicity level such that when the dielectric gas leaks, the effective diluted concentration does not exceed its PEL (i.e., Occupational Exposure Limit (OEL or TLV) of at least about 0.3 ppm); and a dielectric strength greater than air. 0104 Preferably, the electrical equipment is at least one selected from the group consisting of gas-insulated circuit breakers and current-interruption equipment, gas-insulated transmission lines, gas-insulated transformers, and gas-insu lated Substations.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

0105. The compounds of the present disclosure are useful in gaseous phase for electrical insulation and for arc quench ing and current interruption equipment used in the transmis sion and distribution of electrical energy. Generally, there are four major types of electrical equipment which the gases of the present disclosure can be used for insulation and/or inter ruption purposes: (1) gas-insulated circuit breakers and cur rent-interruption equipment, (2) gas-insulated transmission lines, (3) gas-insulated transformers, and (4) gas-insulated Substations. Such gas-insulated equipment is a major compo nent of power transmission and distribution systems all over the world. It offers significant savings in land use, is aestheti cally acceptable, has relatively low radio and audible noise emissions, and enables Substations to be installed in popu lated areas close to the loads. 0106 Depending on the particular function of the gas insulated equipment, the gas properties which are the most significant vary. 0.107 For circuit breakers the excellent thermal conduc tivity and high dielectric strength of Such gases, along with the fast thermal and dielectric recovery (short time constant for increase in resistivity), are the main reasons for its high interruption capability. These properties enable the gas to make a rapid transition between the conducting (arc plasma) and the dielectric state of the arc, and to withstand the rise of the recovery Voltage. 0.108 For gas-insulated transformers the cooling ability, compatibility with sold materials, and partial discharge char acteristics, added to the dielectric characteristics, make them a desirable medium for use in this type of electrical equip ment. The compounds have distinct advantages over oil insu lation, including none of the fire safety problems or environ mental problems related to oil, high reliability, flexible layout, little maintenance, long service life, lower noise, bet ter handling, and lighter equipment.

US 2008/O 135817 A1

0109 For gas-insulated transmission lines the dielectric strength of the gaseous medium under industrial conditions is of paramount importance, especially the behavior of the gas eous dielectric under metallic particle contamination, Switch ing and lightning impulses, and fast transient electrical stresses. These gases also have a high efficiency for transfer of heat from the conductor to the enclosure and are stable for long periods of time (e.g., 40 years). These gas-insulated transmission lines offer distinct advantages: cost effective ness, high-carrying capacity, low losses, availability at all Voltage ratings, no fire risk, reliability, and a compact alter native to overhead high Voltage transmission lines in con gested areas that avoids public concerns with overhead trans mission lines.

0110. For gas-insulated substations, the entire substation (circuit breakers, disconnects, grounding Switches, busbar, transformers, etc., are interconnected) is insulated with the gaseous dielectric medium of the present disclosure, and, thus, all of the above-mentioned properties of the dielectric gas are significant. 0111. The properties of a dielectric gas that are necessary for its use in high Voltage equipment are many and vary depending on the particular application of the gas and the equipment. 0112 Intrinsic properties are those properties of a gas which are inherent in the physical atomic or molecular struc ture of the gas. These properties are independent of the appli cation or the environment in which a gas is placed. One of the desirable properties of a gaseous dielectric is high dielectric strength (higher, for instance than air). The gas properties that are principally responsible for high dielectric strength are those that reduce the number of electrons which are present in an electrically-stressed dielectric gas. To effect Such a reduc tion in the electron number densities, as gas should: (i) be electronegative (remove electrons by attachment over as wide an energy range as possible); it should preferably exhibit increased electron attachment with increasing electron energy and gas temperature since electrons have a broad range of energies and the gas temperature in many applica tions is higher than ambient; (ii) have good electron slowing down properties (slow electrons down so that they can be captured efficiently at lower energies and be prevented from generating more electrons by electron impactionization); and (iii) have low ionization cross section and high ionization onset (prevent ionization by electron impact). Besides the above properties, there are a number of other basic properties which are necessary for the complete characterization of the dielectric gas behavior and its performance in practice, e.g., secondary processes such as electron emission from Surfaces by ion and photon impact; photoprocesses; absorption of photoionizing radiation (this is a controlling factor in dis charge development in non-uniform fields); dissociation under electron impact decomposition; ion-molecule reac tions; reactions with trace impurities; and reactions with Sur faces.

0113. The dielectric gas must also have the following chemical properties: high vapor pressure; high specific heat, high thermal conductivity for gas cooling; thermal stability over long periods of time for temperatures greater than 400° K; chemical stability and inertness with regard to conducting and insulating materials; non-flammable; toxicity acceptable for industrial exposure; and non-explosive. When used in mixtures, it must have appropriate thermodynamic properties for mixture uniformity, composition, and separation.

Jun. 12, 2008

0114 Extrinsic properties are those which describe how a gas may interact with its Surroundings, or in response to external influences, such as electrical breakdown and dis charges. To be used in electrical applications, a dielectric gas should: (undergo no extensive decomposition; lead to no polymerization; form no carbon or other deposits; and be non-corrosive and non-reactive to metals, insulators, spacers, and seals. In addition it should have: no byproduct with tox icity unacceptable for industrial applications; removable byproducts; and a high recombination rate for reforming itself, especially for arc interruption. Finally, the gas must be environmentally friendly, e.g., it must not contribute to global warming, must not deplete stratospheric oZone, and must not persist in the environment for long periods of time. 0115 Specific properties of the gas under discharge and breakdown conditions include: a high breakdown Voltage under uniform and non-uniform electric fields; insensitivity to surface roughness or defects and freely moving conducting particles; good insulation properties under practical condi tions; good insulator flashover characteristics; good heat transfer characteristics; good recovery (rate of Voltage recov ery) and self-healing; no adverse reactions with moisture and common impurities; and no adverse effects on equipment, especially on spacers and electrode surfaces. 0116 Specific properties of gaseous insulators for specific electrical equipment is set forth below: Circuit breakers—The most significant required gas proper ties for arc interruption are: (i) high dielectric strength com parable to that of SF; (ii) high thermal conductivity; (iii) fast gas recovery; and (iv) self-healing/dielectric integrity. Gas-insulated transmission lines—The required properties include: (i) high dielectric strength; (ii) high vapor pressure at operating and ambient temperature; (iii) chemical inertness; (iv) high thermal conductivity; (v) no thermal aging; (vi) no deposits; (vii) easily removable, non-harmful byproducts; and (viii) no unacceptable level of hazards (fire, explosion, toxicity, corrosion). Gas-insulated transformers—The properties of the gas required for this application include: (i) high dielectric strength at reasonable pressures (e.g., 500 kPa); (ii) low boil ing point; (iii) acceptably low toxicity; (iv) chemical inert ness; (V) good thermal stability; (vi) non-flammable; (vii) high cooling capability; (viii) good compatibility with Solid materials; (ix) good partial discharge characteristics; (X) use able over a range of temperatures; and (xi) safe, easy to handle, inexpensive and securely available. 0117 The present inventors have discovered a unique series of dielectric gases for use in electric equipment appli cations, which exhibit many of the aforementioned proper ties, which avoiding the greenhouse problems associated with SF. Such dielectric compounds exhibit at least one of the following properties:

0118. A boiling point in the range between about -20° C. to about -273° C.

0119 Low, preferably, Non-ozone depleting 0120 A GWP less than about 22,200 0121 Chemical stability, as measured by a negative standard enthalpy of formation (dHf<0)

0.122 A toxicity level such that when the working gas leaks from equipment at the manufacturer's specified maximum leak rate, the effective diluted concentration does not its PEL, i.e., does not exceed the PEL of that specific compound. In general with minimal ventilation PELs greater than about 0.3 ppm by volume are accept

US 2008/O 135817 A1

Dielectric Compound

C3

CBrFO CCIF2NO

CF CF

C

C

Structure

CF3- O O. Cl COCIF

F2CH O NO F3COH HFCO HOCN C2 CIF

10

TABLE 1-continued

Name CAS

,1,1,3,3,3- 684-16-2 Hexafluoropropanone pentafluoro-propionyl 422-61-7 fluoride?/perfluoropropionyl fluoride Trifluoromethyl 1187-93-5 trifluorovinyl ether -Propyne 74-99-7

Cyclopropane 75-19-4 Propane 74-98-6 Trimethylborane 593-90-8 cyanoketene 4452-08-8 butatriene 2873-SO-9 Cyano-bispentafluorethyl- 35.449-90-2 phosphin Trimethyl-1,1,2,2- 41 68-08-5 etrafluorethylsilan methyl diborane 23777-55-1 Methyldiboran (germ.) carbonyl bromide fluoride 753-56-0 chloro-difluoro-nitroso- 421-13-6 methane, Chlor-difluor nitroso-methan chloroperoxytrifluoromethane 327SS-26-3 carbonylchlorid-fluorid 353-49-1 Carbonychloridifluorid (germ.) 3,3-difluoro-3#H-diazirine 693-85-6 difluoro diazomethane 814-73-3 Difluordiazomethan (germ.) Carbonyl fluoride 3S3-SO-4 Difluordioxiran 96.740-99-7 difluoro-(3-fluoro-3#H- 4823-43-2 diazirin-3-yl)-amine trifluoromethylazide 3802-95-7 Trifluormethylazid (germ.) etrafluoro-diaziridine 17224-09-8 Fluorperoxytrifluorimethan 34511-13-2 Bis(fluoroxy)difluormethan 16282-67-O Trifluormethyl- 19162-94-8 phosphonylfluorid Cyanogen fluoride 1495-SO-7 Trifluormethylphosphane 420-52-O (germ.) Diazomethane 334-88-3 ormaldehyde?/Formalin SO-OO-O (methyl)difluoroborane 373-64-8 (Methyl)difluorboran (germ.) Chloromethane 74-87-3

methylphosphonous acid difluoridefidifluoro methyl-phosphine

trifluoro-methoxy-silane 2S711-11-9 Methylhypofluorid 36336-08-0 Methane 74-82-8 Methylsilane 992-94-9 #Sil-bromo-#SilitSi!'- 56962-86-8 methanediyl-bis-silane #Si!-iodo-#SilitSi!'- 56962-87-9 methanediyl-bis-silane Difluorimethylnitrit 1493-06-7 trifluoromethanol 1493-11-4 Formyl fluoride 1493-02-3 Cyanic acid 420-05-3 Chlorine 7782-50-5 Chlorine fluoride 7790-89-8 Chlorine trioxide fluoride 7616-94-6 carbon oxide 1603-84-5 selenide? Kohlenoxidselenid Fluorine 77.82-41-4 Difluorosilane 13824-36-7 Fluorine oxide 7783-41-7

MW

166.O2

166.O2

166.O2

40.06 42.08 44.10 55.92 67.05 S2.08

295.02

174.21

41.70

126.91 115.47

136.46 82.46

66.01 82.01

111.03

110.03

116.02 120.00 120.00 153.98

45.02 102.00

42.04 30.03 63.84

SO.49 84.01

116.11 SO.O3 16.04 46.14 1SS.14

2O2.14

97.02 86.01 48.02 43.03 70.91 S4.45 102.45 106.97

38.00 68.10 S400

-27.3

-27.0

-26.0

-23.2 -32.8 -42.0 -20.2 -34.0 -78.0 -78.0

-72.O

-350

-20.6 -350

-22.0 -46.0

-91.3 -91.3

-84.6 -85.0 -36.0

-285

-350 -69.4 -64.0 -20.1

-46.2 -26.5

-23.2 -21.0 -62.3

-24.2 -28.0

-78.0 -33.0

-161.5 -56.9 -64.0

-49.0

-20.0 -20.0 -26.5 -64.2 -34.0

-101.0 -46.7 -21.7

-1882 -77.8

-144.7

Jun. 12, 2008

US 2008/O 135817 A1

Dielectric Compound Structure

FOOF SO2F2 SF2 POF3

PSF3

C

C

CF2-CH2 CHF CHF

FHC-CHF

CHF CHF

11

TABLE 1-continued

Name

fluorine peroxide Sulfuryl fluoride sulphur difluoride Phosphorus trifluoride oxide Phosphorus trifluoride sulfide etrafluorophosphorane Tetrafluorohydrazine Sulfur tetrafluoride hexafluoro disiloxane Hexafluordisiloxan (germ.) Nitryl fluoride Hydrogen Hydrogen selenide Phosphorus trihydride Germanium hydride Silane Tin tetrahydride Oxygen Ozone Antimony monophosphide Disilicon monophosphide Radon Argon Trifluoroborane Hydrogen bromide Bromopentafluoroethane Chlorotrifluoroethene Trifluoroacetonitrile trifluoromethyl isocyanate

pentafluoro-nitroso ethane, Pentafluor-nitroso aethan (trifluoromethyl-carbonyl)- difluoro-amine Hexafluoroethane Bis-trifluormethyl-nitroxid bis-trifluoromethyl ether bis(trifluoromethyl)tellurium bis(trifluoromethyl) ditelluride N,N-Difluor pentafluoraethylamin (germ.) N-Fluor-bis(trifluorimethyl)- amin (germ.) N-Fluor-N-trifluormethoxy perfluorimethylamin (germ.) fluoroformyl cyanide 1-chloro-1-fluoro-ethene, 1 Chlor-1-fluor-aethen 1 chloro-1-fluoroethylene 1,1-Difluoroethene #trans-1,2-difluoro ethenefiti trans-vinylene difluoride? (E)-1,2- difluoroethylene? (E)-1,2- difluoro-ethenefiti trans vinylene fluoride 1,2-difluoro-ethenefiticist vinylene difluoride?/1,2- Difluor-aethen vinylene fluoride #cis-1,2-difluoro ethenefiticist-vinylene difluoride? (Z)-1,2- difluoroethylene, f(Z)-1,2- difluoro-ethenefiticist vinylene fluoride 1,1,1,2-Tetrafluoroethane

CAS

7783-44-0 2699-79-8 13814-25-0 13478-20-1

13659-66-0 10O36-47-2 7783-60-0 1451S-39-0

10O22-SO-1 1333-74-0 7783-07-5 78O3-51-2 7782-6S-2 78O3-62-5 24O6-52-2 7782-44-7 10O28-15-6 l

l

10043-92-2 7440-37-1 7637-07-2 10O3S-1O-6 354-55-2 79-38-9 353-85-5 460-49-1

trifluoromethylthiocarbonyl fluoride Trifluorimethylthiocarbonylfluorid (germ.)

32822-49-4

76-16-4 2154-71-4 1479–49-8 SS642-42-7 1718-20-3

359-62-6

4217-92-9

683-55-6 2317-91-1

75-38-7 1630-78-0

1691-13-O

1630-77-9

811-97-2

MW

70.00 102.06 70.06 103.97

120.03

107.98 104.01 108.OS 186.16

6S.OO 2.02

80.98 34.00 76.62 32.12 122.72 32.00 48.00 152.72 87.14

222.00 39.95 67.81 80.91 98.92 16.47 95.02 11.02 32.08

49.02

71.02

87.02

73.03 80.49

64.03 64.03

64.03

64.03

102.03

-S7.0 -SS3 -350 -39.7

-52.3

-37.0 -74.2 -40.5 -23.0

-72.3 -2529 -41.3 -87.8 -88.2

-112.2 -51.8

-183.0 -111.3 -52.3 -52.3 -61.7 -1859 -101.2 -66.7 -21.0 -28.4 - 68.8 -36.0 -21.0

-45.7

-21.1

-78.2 -20.0 -59.0 -98.0 -53.0

-38.0

-37.0

-25.0

-21.0 -2S.S

-85.7 -53.1

-28.0

-26.0

-26.1

Jun. 12, 2008

US 2008/O 135817 A1

Dielectric Compound

F5 FSO

CC

CC

12

TABLE 1-continued

Structure

CH2CFCH3 CH2CHCH3

F3C O Cl CF2C OF

CCF2 NF2

Name

1.22-Tetrafluoroethane luoroethene 1,1-Trifluoroethane

Ether, methyl trifluoromethyl Ethene ,1-Difluoroethane

8le

fluoro-dimethyl-borane Disiloxane, 1,1,3,3- etrafluoro-1,3-dimethyl Trifluoroethene trifluoroacetaldehyde?/Trifluor acetaldehy Pentafluoroethane Difluoromethyl trifluoromethyl ether Tris(trifluoromethyl)bismuth etrafluoropropadienefitetrafluoro allene? (1,1,3,3- etrafluoro-1,2-propadiene etrafluorocyclopropene Perfluoropropionyliodid pentafluoropropionitrile?/ pentafluoropropiononitrile (X8OO

cyclopropane? Hexafluor cyclopropan freon-#C216 Hexafluoropropylene hexafluoro-1,3dioxolane Octafluoropropane Perfluormethylethylether 1-difluoro

propadiene fallenylidene difluoride? 1,1-difluoro allene 2,3,3,3-tetrafluoro propene/HFO-1234yf EranSHFO-1234ze 3,3,3-Trifluoropropene cyclopropene Allene 1-difluoro

propenef propenylidene difluoride? 1,1-Difluor Oel

methylketene 2-fluoropropene -Propene DL-2-aminopropanoic acid 3,3,3-trifluoro propyne? (3,3,3-Trifluor propini?trifluoromethyl ethyne? (3,3,3-trifluoro-1- propyne 1,1,3,3,3-pentafluoro propenef, 1,1,3,3,3- Pentafluor-propen ,2,3,3,3-pentafluoro

propene

1,144.4-hexafluoro-2- butyne 144-tetrafluoro-butane

2,3-dione

Trifluormethylhypochlorit Chlor-difluor-methyl hypofluorit N-Chlor-N-fluor trifluorimethylamin (germ.) Chlordifluordifluoraminomethan

CAS

359-35-3 75-02-5 420-46-2 421-14-7

74-85-1 75-37-6 3S3-36-6 74-84-O 353-46-8 63O89-45-2

359-11-5 75-90-1

354-33-6 3822-68-2

S863-80-9 461-68-7

19721-29-O 137741-03-8 422-04-8

931-91-9

116-15-4 21297-65-4 76-19-7 665-1 6-7 430-64-8

754-12-1

677-21-4 2781-85-3 463-49-O 430-63-7

6004-44-0 1184-60-7 115-07-1 302-72-7 661-54-1

690-27-7

2252-83-7

692-50-2

22082-78-6 2O614-17-9

1388O-72-3

13880-71-2

MW

102.03 46.04 84.04 100.04

28.05 66.OS 48.06 30.07 59.88 178.23

82O2 98.02

2O.O2 36.02

416.00 12.03

12.03 273.93 45.03

SO.O2 82O2 88.02

204.O2 76.05

114.04

114.04 96.OS 40.06 40.06 78.06

56.06 60.07 42.08 89.09 94.04

32.03

32.03

62.03

58.05

14.10 20.46 20.46

37.46

37.46

-23.0 -72.2 -47.3 -24.0

-103.7 -24.0 -37.7 -88.6 -44.0 -39.0

-510 -21.0

-48.1 -35.3

-SS.O -38.0

-20.0 -27.0 -350

-33.0

-29.6 -22.1 -36.7 -20.0 -21.0

-28.3

-19.0 -25.0 -36.0 -34.5 -29.0

-23.0 -24.0 -47.7 -50.2 -48.0

-21.0

-20.0

-24.6

-81.0

-33.0 -47.0 -25.0

-32.8

-28.0

Jun. 12, 2008

US 2008/O 135817 A1

Dielectric Compound

CF

CFSN

CFSNO CFSNO2

CFSNS

CFSP

C

Structure

SFSCN

SCF3 HCI SH3C CO CO2 OCS NHF2 FNNF FNNF F2SO

13

TABLE 1-continued

Name CAS

thiocarbonyl difluoride 420-32-6 Thiocarbonyldifluorid (germ.) selenocarbonyl difluoride S4393-39-4 Trifluoroiodomethane 2314-97-8 N-Fluor-difluorimethanimin 338-66-9 (germ.) trifluoro-nitroso- 334-99-6 methane, Trifluor-nitroso methan difluoro-carbamoyl fluoride 2368-32-3 trifluoro-nitro- 335-02-4 methane, Trifluor-nitro methan fluoropicrin Tetrafluoromethane 75-73-0 Tetrafluorformamidin 14362-70-0 (germ.) etrafluorourea 10256-92-5

hypofluorous acid trifluoromethylester?, Hypofluorigsa.eure

trifluorimethylesteri?trifluoromethyl hypofluorite

trifluoromethanesulfonyl 335-05-7 fluoride N,N-Difluor- 335-01-3 trifluorimethylamin (germ.) Trifluormethyloxydifluoramin 4217-93-O (Difluoraminoxy)difluorimethyl- 36781-60-9 hypofluorit Sulfurcyanide pentafluoride 1512-13-6 Schwefelcyanid pentafluorid (germ.) difluoro-trifluoromethyl- 1112-04-5 phosphine Hexafluorimethandiamin 4394-93-8 perfluoro methylsilane 335-06-8 Perfluormethylsilan (germ.) Trifluormethyl- 1184-81-2 etrafluorphosphoran (germ.) Difluoromethane 75-10-5 Fluoroiodomethane 373-53-5 fluoromethanet methyl 593-53-3 fluoride, Fluormethan reon-41 trifluoromethyl-silane' 1O112-11-5 CF3SH3 methyltrifluorosilane 373-74-0 difluoro-methyl-silane 420-34-8 fluoro-methyl-silane 753-44-6 methylgermane 449-65-6 Difluorformimin 2712-98-3 Trifluoromethane 75-46-7 trifluoromethane thiol 493-15-8 Trifluormethanthiol (germ.) N,N,1,1- 24708-53-0 Tetrafluormethylamin difluoro dichlorosilane 8356-71-3 Difluordichlorsilan (germ.) difluoro chlorosilane 8OOO3-43-6 Difluorchlorsilan (germ.) Phosphorus chloride 4335-40-1 difluoride Chlorotrifluorosilane 4049-36-6 Hydrogen chloride 7647-01-0 Chlorosilane 3465-78-6 Carbon monoxide 630-08-0 Carbon dioxide 24-38-9 Carbonyl sulfide 463-58-1 Difluoramine O405-27-3 trans-Difluorodiazine 3776-62-O cis-Difluorodiazine 3812-43-6 Thionyl fluoride 7783-42-8

MW

82.07

128.97 195.91 83.01

99.01

99.01 15.01

88.00 16.O2

52.07

21.01

37.01 53.01

53.08

37.98

54.O1 54.09

75.97

S2.O2 59.93 34.03

OO.12

OO.12 82.12 64.13 90.65 6S.O2 70.01 102.08

103.02

136.99

102.56

104.42

120.53 36.46 66.56 28.01 44.01 60.07 53.01 66.01 66.01 86.06

-46.0

-28.0 -21.8

-101.0

-86.0

-52.0 -33.6

-128.1 -3O.O

-20.0 -95.0

-21.7

-7S.O

-59.8 -29.0

-25.0

-43.0

-37.0 -42.0

-350

-51.7 -53.8 -78.3

-383

-3O.O -35.6 -44.0 -23.0 -22.0 -82.1 -36.7

-43.0

-31.8

-500

-47.3

-70.2 -85.0 -303 -1915 -78.4 -50.3 -23.2

-111.5 -105.8 -43.8

Jun. 12, 2008

US 2008/O 135817 A1

Dielectric Compound

0125

Structure

SHF3 NF3 NOF3 NSF3 PF3 GeF4 SF4 PF5 SeF6 TeF6 SH3F

HI

N2 NNO Ne NO

14

TABLE 1-continued

Name

Trifluorosilane Nitrogen trifluoride Trifluoramine oxide thiazyl trifluoride Phosphorus trifluoride Germanium(IV) fluoride Tetrafluorosilane Phosphorus pentafluoride Selenium hexafluoride Tellurium hexafluoride fluorosilane Nitrosyl fluoride Fluorine nitrate Hydrogen sulfide Ammonia Helium Hydrogen iodide Krypton Nitrogen dinitrogen oxide Neon Nitrogen oxide Xenon

The preferred dielectric compounds are selected from the group consisting of those set forth in Table 2 below:

Dielectric Compound Structure

Air

C

CF2-CH2 CHF CHF

TABLE 2

Name

Argon Trifluoroborane Hydrogen bromide Bromopentafluoroethane Chlorotrifluoroethene Trifluoroacetonitrile trifluoromethyl isocyanate

pentafluoro-nitroso ethane, Pentafluor-nitroso aethan (trifluoromethyl-carbonyl)- difluoro-amine Hexafluoroethane Bis-trifluorimethyl-nitroxid bis-trifluoromethyl ether bis(trifluoromethyl)tellurium bis(trifluoromethyl) ditelluride N,N-Difluor pentafluoraethylamin (germ.) N-Fluor-bis(trifluorimethyl)- amin (germ.) N-Fluor-N-trifluormethoxy perfluorimethylamin (germ.) fluoroformyl cyanide 1-chloro-1-fluoro-ethene, 1 Chlor-1-fluor-aethen 1 chloro-1-fluoroethylene 1,1-Difluoroethene #trans-1,2-difluoro ethenefiti trans-vinylene difluoride? (E)-1,2- difluoroethylene? (E)-1,2-

CAS

13465-71-9 7783-54-2 13847-6S-9 15930-75-3 7783-55-3 7783-58-6 7783-61-1 7647-19-0 7783-79-1 7783-80-4 13537-33-2 7789-25-5 7789-26-6 7783-06-4 7664-41-7 7440-59-7 10O34-85-2 7439-90-9 7727-37-9 10O24-97-2 7440-01-9 10102-43-9 7440-63-3

CAS

7440-37-1 7637-07-2 10O3S-1O-6 354-55-2 79-38-9 353-85-5 460-49-1

trifluoromethylthiocarbonyl fluoride Trifluorimethylthiocarbonylfluorid (germ.)

32822-49-4

76-16-4 2154-71-4 1479–49-8 SS642-42-7 1718-20-3

359-62-6

4217-92-9

683-55-6 2317-91-1

75-38-7 1630-78-0

MW

86.09 71.OO 87.00

103.07 87.97

148.58 104.08 125.97 192.95 241.59 SO.11 49.00 81.00 34.08 17.03 4.OO

127.91 83.80 28.01 44.01 20.18 30.01 131.29

MW

39.95 67.81 80.91 98.92 16.47 95.02 11.02 32.08

49.02

71.02

87.02

73.03 80.49

64.03 64.03

-95.2 -129.1 -87.5 -27.1

-101.5 -36.5 -86.0 -84.5 -46.5 -38.8 -98.0 -59.9 -46.2 -59.5 -33.3

-268.9 -35.6 -1534 -1958 -88.5

-246.1 -151.8 -108.1

-1859 -101.2 -66.7 -21.0 -28.4 - 68.8 -36.0 -21.0

-45.7

-21.1

-78.2 -20.0 -59.0 -98.0 -53.0

-38.0

-37.0

-25.0

-21.0

-85.7 -53.1

Jun. 12, 2008

US 2008/O 135817 A1

Dielectric Compound

15

TABLE 2-continued

Structure

FHC-CHF

CHF CHF

C C C C

CH2CFCH3 CH2CHCH3

CF3 CF CFEH

Name

difluoro-ethenefiti trans vinylene fluoride 1,2-difluoro-ethenefiticist vinylene difluoride?/1,2- Difluor-aethen vinylene fluoride #cis-1,2-difluoro ethenefiticist-vinylene difluoride? (Z)-1,2- difluoroethylene, f(Z)-1,2- difluoro-ethenefiticist vinylene fluoride ,1,1,2-Tetrafluoroethane 1.22-Tetrafluoroethane

Fluoroethene 1,1-Trifluoroethane

Ether, methyl trifluoromethyl Ethene ,1-Difluoroethane Fluoroethane Ethane fluoro-dimethyl-borane Disiloxane, 1,1,3,3- etrafluoro-1,3-dimethyl Trifluoroethene trifluoroacetaldehyde?/Trifluor acetaldehy Pentafluoroethane Difluoromethyl trifluoromethyl ether Tris(trifluoromethyl)bismuth etrafluoropropadienefitetrafluoro allene? (1,1,3,3- etrafluoro-1,2-propadiene etrafluorocyclopropene Perfluoropropionyliodid pentafluoropropionitrile?/ pentafluoropropiononitrile hexafluorocyclopropane?. Hexafluorcyclopropan. reon-iiCl216 Hexafluoropropylene hexafluoro-1,3dioxolane Octafluoropropane Perfluormethylethylether 1-difluoro

propadiene fallenylidene difluoride? 1,1-difluoro allene 2,3,3,3-tetrafluoro propene/HFO-1234yf EranSHFO-1234ze 3,3,3-Trifluoropropene cyclopropene Allene ,1-difluoropropenefit

propenylidene difluoride?/1,1-Difluorpropen methylketene 2-fluoropropene -Propene DL-2-aminopropanoic acid 3,3,3-trifluoro propyne? (3,3,3-Trifluor propini?trifluoromethyl ethyne? (3,3,3-trifluoro-1- propyne 1,1,3,3,3-pentafluoro propenef, 1,1,3,3,3- Pentafluor-propen ,2,3,3,3-pentafluoro

propene

CAS

1691-13-O

1630-77-9

811-97-2 359-35-3 75-02-5 420-46-2 421-14-7

74-85-1 75-37-6 3S3-36-6 74-84-O 353-46-8 63O89-45-2

359-11-5 75-90-1

354-33-6 3822-68-2

S863-80-9 461-68-7

19721-29-O 137741-03-8 422-04-8

931-91-9

116-15-4 21297-65-4 76-19-7 665-1 6-7 430-64-8

754-12-1

677-21-4 2781-85-3 463-49-O 430-63-7

6004-44-0 1184-60-7 115-07-1 302-72-7 661-54-1

690-27-7

2252-83-7

MW

64.03

64.03

SO.O2 82O2 88.02

204.O2 76.05

114.04

114.04 96.OS 40.06 40.06 78.06

56.06 60.07 42.08 89.09 94.04

132.03

132.03

-28.0

-26.0

-26.1 -23.0 -72.2 -47.3 -24.0

-103.7 -24.0 -37.7 -88.6 -44.0 -39.0

-510 -21.0

-48.1 -35.3

-SS.O -38.0

-20.0 -27.0 -350

-33.0

-29.6 -22.1 -36.7 -20.0 -21.0

-28.3

-19.0 -25.0 -36.0 -34.5 -29.0

-23.0 -24.0 -47.7 -50.2 -48.0

-21.0

-20.0

Jun. 12, 2008

US 2008/O 135817 A1

Dielectric Compound

CFSNO CFSNO2

CFSNS

CFSP

C

C

Structure

F3C O Cl CF2C OF

SFSCN

16

TABLE 2-continued

Name

1,1,144.4-hexafluoro-2- butyne 1,144-tetrafluoro-butane 2,3-dione

Trifluormethylhypochlorit Chlor-difluor-methyl hypofluorit N-Chlor-N-fluor trifluorimethylamin (germ.) Chlordifluordifluoraminomethan thiocarbonyl difluoride Thiocarbonyldifluorid (germ.) selenocarbonyl difluoride Trifluoroiodomethane N-Fluor-difluorimethanimin (germ.) trifluoro-nitroso methane, Trifluor-nitroso methan difluoro-carbamoyl fluoride trifluoro-nitro methane, Trifluor-nitro methan fluoropicrin Tetrafluoromethane Tetrafluorformamidin (germ.) etrafluorourea

trifluoromethanesulfonyl fluoride N,N-Difluor trifluorimethylamin (germ.) Trifluormethyloxydifluoramin (Difluoraminoxy)difluorimethyl hypofluorit Sulfurcyanide pentafluoride Schwefelcyanid pentafluorid (germ.) difluoro-trifluoromethyl phosphine Hexafluorimethandiamin perfluoro methylsilane Perfluormethylsilan (germ.) Trifluormethyl etrafluorphosphoran (germ.) Difluoromethane Fluoroiodomethane fluoromethanet methyl fluoride, Fluormethan reon-41 trifluoromethyl-silane' CF3SH3 methyltrifluorosilane difluoro-methyl-silane fluoro-methyl-silane methylgermane Difluorformimin Trifluoromethane trifluoromethane thiol Trifluormethanthiol (germ.) N,N,1,1- Tetrafluormethylamin difluoro dichlorosilane Difluordichlorsilan (germ.) difluoro chlorosilane Difluorchlorsilan (germ.) Phosphorus chloride difluoride

CAS

692-50-2

22082-78-6 2O614-17-9

1388O-72-3

13880-71-2 420-32-6

S4393-39-4 2314-97-8 338-66-9

334-99-6

2368-32-3 335-02-4

75-73-0 14362-70-0

10256-92-5 hypofluorous acid trifluoromethyl

ester? Hypofluorigsaeure trifluorimethylesteri?trifluoromethylhypofluorite

335-05-7

335-01-3

4217-93-O 36781-60-9

1512-13-6

1112-04-5

4394-93-8 335-06-8

1184-81-2

75-10-5 373-53-5 593-53-3

1O112-11-5

373-74-0 420-34-8 753-44-6 1449-65-6 2712-98-3 75-46-7 1493-15-8

24708-53-0

18356-71-3

8OOO3-43-6

14335-40-1

MW

62.03

58.05

14.10 20.46 20.46

37.46

37.46 82.07

28.97 95.91 83.01

99.01

99.01 15.01

88.00 16.O2

32.O2

52.07

21.01

37.01 53.01

53.08

37.98

54.O1 54.09

75.97

S2.O2 59.93 34.03

OO.12

OO.12 82.12 64.13 90.65 6S.O2 70.01 102.08

103.02

136.99

102.56

104.42

-24.6

-81.0

-33.0 -47.0 -25.0

-32.8

-28.0 -46.0

-28.0 -21.8

-101.0

-86.0

-52.0 -33.6

-128.1 -3O.O

-20.0 -95.0

-21.7

-7S.O

-59.8 -29.0

-25.0

-43.0

-37.0 -42.0

-350

-51.7 -53.8 -78.3

-383

-3O.O -35.6 -44.0 -23.0 -22.0 -82.1 -36.7

-43.0

-31.8

-500

-47.3

Jun. 12, 2008

US 2008/O 135817 A1 17

TABLE 2-continued

Dielectric Compound Structure Name

CF3S SCF3 Chlorotrifluorosilane CH HCI Hydrogen chloride CH3S SH3C Chlorosilane CO CO Carbon monoxide CO2 CO2 Carbon dioxide COS OCS Carbonyl sulfide F2HN NHF2 Difluoramine F2N2 FNNF trans-Difluorodiazine F2N2 FNNF cis-Difluorodiazine F2OS F2SO Thionyl fluoride F3HS SHF3 Trifluorosilane F3N NF3 Nitrogen trifluoride F3NO NOF3 Trifluoramine oxide F3NS NSF3 thiazyl trifluoride F3P PF3 Phosphorus trifluoride F4Ge GeF4 Germanium(IV) fluoride F4S. SF Tetrafluorosilane

PF5 Phosphorus pentafluoride F6Se SeF6 Selenium hexafluoride F6Te TeF6 Tellurium hexafluoride FH3S SH3F fluorosilane FNO Nitrosyl fluoride FNO3 Fluorine nitrate H2S H2S Hydrogen sulfide H3N NH3 Ammonia He He Helium HI H Hydrogen iodide Kr Kr Krypton N2 N2 Nitrogen N2O NON Nitrous oxide Ne Ne Neon NO NO Nitrogen oxide Xe Xe Xenon

0126 The aforementioned dielectric compounds may be

Jun. 12, 2008

used in pure form, but can also be used as part of an azeotrope, or a mixture with an appropriate second gas, i.e., nitrogen, CO, or N.O. 0127 Particularly preferred non-electrical properties for dielectric gases according to the present disclosure, include:

0128 Non-liquefying, e.g., T. less than -20°C. I0129. Chemically stable—decomposition temperature must be higher than hot spot temperature in equipment, e.g., T 200° C., and gas should not decompose in partial discharge spark (approximately 1000 K)

0.130 Low environmental impact, i.e., little to no destruction of ozone layer ODP=0; and low global warming impact GWP less than SF

I0131. Acceptably low toxicity of gas and discharge byproducts

0132 Electrical equipment property requirements for dielectric gases according to the present disclosure, include:

0.133 Insulation specific criteria include a critical field of E, and no conducting decomposition products should be generated by discharge

0.134 Switching specific criteria include high critical field of E, arcing stability, i.e., a gas must recombine to original molecular structure after being decomposed in switching arc (Gibbs free energy of reaction is <0)

0.135 Specific thermal interruption performance, i.e., must be able to interrupt current flow at accurrent Zero

0.136 Arc erosion product from equipment and gas must not form conduction deposits

I0137 Low velocity of sound

MY CAS MW BP(° C.)

14049-36-6 120.53 -702 7647-01-0 36.46 -85.0 13465-78-6 66.56 -30.3 630-08-0 28.01 -1915 124-38-9 44.01 -78.4 463-58-1 60.07 -SO3 1040S-27-3 53.01 -23.2 13776-62-0 66.01 -111.5 13812-43-6 66.01 -105.8 7783-42-8 86.06 -43.8 13465-71-9 86.09 -95.2 7783-54-2 71.OO -129.1 13847-6S-9 87.00 -87.5 15930-7S-3 103.07 -27.1 7783-55-3 87.97 -101.5 7783-58-6 148.58 -36.5 7783-61-1 104.08 -86.0 7647-19-0 125.97 -84.5 7783-79-1 192.95 -46.5 7783-80-4 241.59 -38.8 13537-33-2 50.11 -98.0 7789-25-5 49.00 -59.9 7789-26-6 81.00 -46.2 7783-06-4 34.08 -59.5 7664-41-7 17.03 -33.3 7440-59-7 4.00 -268.9 10O34-85-2 127.91 -35.6 7439-90-9 83.80 -1534 7727-37-9 28.01 - 1958 10O24-97-2 44.01 -88.5 7440-01-9 20.18 -246.1 10102-43-9 3O.O1 -151.8 7440-63-3 131.29 -108.1

EXAMPLE 1.

0.138 Measurements of the dielectric strength of potential alternatives were determined using ASTM D2477 or obtained from literature. These measurements were performed at 1 atmosphere pressure across a 0.1 inch gap and at ambient temperature. 0.139. In the intended applications, the gas will not be at 1 atmosphere pressure but at a higher pressure. In this example 5 atmospheres pressure is used as a maximum pressure. If the gas liquefies at a lower pressure than that pressure was used. These gases have higher dielectric strengths and break down Voltages than air. Using 5 atmospheres (73.5 psia) pressure as the upper pressure (rating of the equipment).

Breakdown voltage at Dielectric strength Pressure maximum pressure

Gas kVO.1 inch gap (psia) (kVO.1 inch gap)

Air 4.75 73.5 23.75 R143a 5.8 73.5 29 R152a. 5.9 73.5 29.5 R12S 6.4 73.5 32 R134a 6.6 73.5 33 R22 7.2 73.5 39.9 R124 10.4 55.5 39.3 SF6 14.O 73.5 70 C318 16.O 45.3 49.3 R115 16.O 73.6 8O R114 17.0 31.1 36

US 2008/O 135817 A1

EXAMPLE 2

0140. The dielectric strength of additional gases is mea Sure at 1 atmosphere and at the maximum system pressure. Their breakdown voltages are found to be greater then air, which allows Smaller gaps and therefore Smaller equipment then would be need if air was used. Here the measurements were performed on CTFE (Chlorotrifluoroethylene), HCl (hydrogen chloride) and SiF4 (silicon tetrafluoride). 0141 Having described the invention in detail by refer ence to the preferred embodiments and specific examples thereof, it will be apparent that modifications and variations are possible without departing from the spirit and scope of the disclosure and claims. What is claimed is: 1. A dielectric gaseous compound which exhibits the fol

lowing properties: a boiling point in the range between about -20°C. to about

-273° C.; low non-oZone depleting: a GWP less than about 22,200; chemical stability, as measured by a negative standard

enthalpy of formation (dHf-0); a toxicity level such that when the dielectric gas leaks, the

effective diluted concentration does not exceed its PEL in the working environment; and

a dielectric strength greater than air. 2. The dielectric gaseous compound according to claim 1,

wherein said dielectric gaseous compound is at least one compound selected from the group consisting of:

Arsenic pentafluoride Arsine Diboron tetrafluoride Diborane Perchloric acid, 2-chloro-1,1,2,2-tetrafluoroethyl ester

(9CI) Perchloric acid, 1.2.2-trichloro-1,2-difluoroethyl ester Trifluoroacetyl chloride trifluoromethylisocyanide (CF3-NC) trifluoromethyl isocyanide trifluoro-nitroso-ethene?/Trifluor-nitroso-aethen Tetrafluoroethene 3,3,4,4-tetrafluoro-3,4-dihydro-1,2diazete (Difluoramino)difluoracetonitril Tetrafluorooxirane Trifluoroacetyl fluoride Perfluorimethylfluorformiat trifluoro-acetyl hypofluorite perfluoro-2-aza-1-propene Perfluor-2-aza-1-propen (germ.) N-Fluor-tetrafluor-1-aethanimin (germ.) 3.3-difluoro-2-trifluoromethyl-oxaziridine bis-trifluoromethyl-diazene/hexafluoro-icis

aZomethane Fluoroxypentafluoroethane bis-trifluoromethyl peroxide 1,1-Bis(fluoroxy)tetrafluoroaethan Hexafluorodimethyl sulfide 3-fluoro-3HH-diazirine-3-carbonitrile Ethyne 1,2,2-trifluoro-aziridine Ketene (difluoro)vinylboran (Difluor) vinylboran (germ.) trifluoro-vinyl-silane

Jun. 12, 2008

Ethinylsilan ethyl-difluor-borane Ethyl-difluor-boran (germ.) methyl-methylen-amine Dimethyl ether vinyl-silane Dimethylsilane Chloroethyne fluoroethyne/fluoro-acetylene Ethanedinitrile tetrafluoropropyne?/1,3,3,3-tetrafluoropropyne hexafluoro-oxetane Trifluoro(trifluoromethyl)oxirane 1,1,1,3,3,3-Hexafluoropropanone pentafluoro-propionyl fluoride/perfluoropropionyl fluo

ride Trifluoromethyl trifluorovinyl ether 1-Propyne Cyclopropane Propane Trimethylborane cyanoketene butatriene Cyano-bispentafluorethyl-phosphin Trimethyl-1,1,2,2-tetrafluorethylsilan methyl diborane Methyldiboran (germ.) carbonyl bromide fluoride chloro-difluoro-nitroso-methane?/Chlor-difluor-nitroso

methan chloroperoxytrifluoromethane carbonylchlorid-fluorid Carbonychlorid fluorid (germ.) 3,3-difluoro-3HH-diazirine difluoro diazomethane Difluordiazomethan (germ.) Carbonyl fluoride Difluordioxiran difluoro-(3-fluoro-3#H!-diazirin-3-yl)-amine trifluoromethylazide Trifluormethylazid (germ.) tetrafluoro-diaziridine Fluorperoxytrifluorimethan Bis(fluoroxy)difluormethan Trifluormethyl-phosphonylfluorid Cyanogen fluoride Trifluorimethylphosphane (germ.) Diazomethane formaldehyde/Formalin (methyl)difluoroborane (Methyl)difluorboran (germ.) Chloromethane methylphosphonous acid difluoride/difluoro-methyl

phosphine trifluoro-methoxy-silane Methylhypofluorid Methane Methylsilane #Si-bromo-it-Sili Si'-methanediyl-bis-silane #Si-iodo-it-Sili Si'-methanediyl-bis-silane Difluormethylnitrit trifluoromethanol Formyl fluoride Cyanic acid

US 2008/O 135817 A1

Chlorine Chlorine fluoride Chlorine trioxide fluoride carbon oxide selenide/Kohlenoxidselenid Fluorine Difluorosilane Fluorine oxide fluorine peroxide Sulfinuryl fluoride sulphur difluoride Phosphorus trifluoride oxide Phosphorus trifluoride sulfide tetrafluorophosphorane Tetrafluorohydrazine Sulfur tetrafluoride hexafluoro disiloxane Hexafluordisiloxan (germ.) Nitryl fluoride Hydrogen Hydrogen selenide Phosphorus trihydride Germanium hydride Silane Tin tetrahydride Oxygen OZone Antimony monophosphide Disilicon monophosphide Radon Argon Trifluoroborane Hydrogen bromide Bromopentafluoroethane Chlorotrifluoroethene Trifluoroacetonitrile trifluoromethyl isocyanate trifluoromethylthiocarbonyl fluoride Trifluormethylthiocarbonylfluorid (germ.) pentafluoro-nitroso-ethane//Pentafluor-nitroso-aethan (trifluoromethyl-carbonyl)-difluoro-amine Hexafluoroethane Bis-trifluormethyl-nitroxid bis-trifluoromethyl ether bis(trifluoromethyl)tellurium bis(trifluoromethyl)ditelluride N,N-Difluor-pentafluoraethylamin (germ.) N-Fluor-bis(trifluorimethyl)-amin (germ.) N-Fluor-N-trifluorimethoxy-perfluormethylamin (germ.) fluoroformyl cyanide 1-chloro-1-fluoro-ethene/71-Chlor-1-fluor-aethen/71

chloro-1-fluoroethylene 1,1-Difluoroethene itrans-1,2-difluoro-ethene/#trans-vinylene difluoride/

(E)-1,2-difluoroethylene/7(E)-1,2-difluoro-ethene/ itrans-vinylene fluoride

1,2-difluoro-ethene//icis-Vinylene luor-aethen//vinylene fluoride

icis-1,2-difluoro-ethene/icis-Vinylene difluoride//(Z)- 1,2-difluoroethylene/(Z)-1,2-difluoro-ethene/icis vinylene fluoride

1,1,1,2-Tetrafluoroethane 1,1,2,2-Tetrafluoroethane Fluoroethene 1,1,1-Trifluoroethane

difluoride?/1,2-Dif

19 Jun. 12, 2008

Ether, methyl trifluoromethyl Ethene 1,1-Difluoroethane Fluoroethane Ethane fluoro-dimethyl-borane Disiloxane, 1,1,3,3-tetrafluoro-1,3-dimethyl-Trifluoroet

hene trifluoroacetaldehyde?/Trifluor-acetaldehyd Pentafluoroethane Difluoromethyl trifluoromethyl ether Tris(trifluoromethyl)bismuth tetrafluoropropadiene/tetrafluoro-allene?/1,1,3,3-tet

rafluoro-1,2-propadiene tetrafluorocyclopropene Perfluoropropionyliodid pentafluoro-propionitrile?/pentafluoropropiononitrile hexafluoro-cyclopropane?/Hexafluor-cyclopropan//freon

HCl216 Hexafluoropropylene hexafluoro-1,3dioxolane Octafluoropropane Perfluormethylethylether 1,1-difluoro-propadiene/allenylidene difluoride?/1,1-dif

luoro-allene 2,3,3,3-tetrafluoro-propene/HFO-1234yf trans. HFO-1234ze 3,3,3-Trifluoropropene cyclopropene Allene 1,1-difluoro-propene/propenylidene difluoride?/1,1-Dif

luor-propen methylketene 2-fluoropropene 1-Propene DL-2-aminopropanoic acid 3,3,3-trifluoro-propyne/3.3.3-Trifluor-propin/trifluo

romethyl-ethyne/3,3,3-trifluoro-1-propyne 1,1,3,3,3-pentafluoro-propene/1,1,3,3,3-Pentafluor-pro pen 1.2.3,3,3-pentafluoro-propene

1.1.1.4.4.4-hexafluoro-2-butyne 1,1,4,4-tetrafluoro-butane-2,3-dione Trifluormethylhypochlorit Chlor-difluor-methyl-hypofluorit N-Chlor-N-fluor-trifluorimethylamin (germ.) Chlordifluordifluoraminomethan thiocarbonyl difluoride Thiocarbonyldifluorid (germ.) selenocarbonyl difluoride Trifluoroiodomethane N-Fluor-difluorimethanimin (germ.) trifluoro-nitroso-methane/Trifluor-nitroso-methan difluoro-carbamoyl fluoride trifluoro-nitro-methane/Trifluor-nitro-methan//fluoropi

crin Tetrafluoromethane Tetrafluorformamidin (germ.) tetrafluorourea hypofluorous acid trifluoromethyl ester//Hypofluorigsae

ure-trifluormethylester//trifluoromethyl hypofluorite trifluoromethanesulfonyl fluoride N,N-Difluor-trifluorimethylamin (germ.) Trifluormethyloxydifluoramin (Difluoraminoxy)difluorimethylhypofluorit

US 2008/O 135817 A1

sulfurcyanide pentafluoride Schwefelcyanid-pentafluorid (germ.) difluoro-trifluoromethyl-phosphine Hexafluorimethandiamin perfluoro methylsilane Perfluorimethylsilan (germ.) Trifluormethyl-tetrafluorphosphoran (germ.) Difluoromethane Fluoroiodomethane fluoromethane/methyl fluoride/Fluor-methan//freon-41 trifluoromethyl-silane” CF3SiH3 methyltrifluorosilane difluoro-methyl-silane fluoro-methyl-silane methyl germane Difluorformimin Trifluoromethane trifluoromethane thiol Trifluormethanthiol (germ.) N.N.,1,1-Tetrafluormethylamin difluoro dichlorosilane Difluordichlorsilan (germ.) difluoro chlorosilane Difluorchlorsilan (germ.) Phosphorus chloride difluoride Chlorotrifluorosilane Hydrogen chloride Chlorosilane Carbon monoxide Carbon dioxide Carbonyl sulfide Difluoramine trans-Difluorodiazine cis-Difluorodiazine Thionyl fluoride Trifluorosilane Nitrogen trifluoride Trifluoramine oxide thiazyl trifluoride Phosphorus trifluoride Germanium(IV) fluoride Tetrafluorosilane Phosphorus pentafluoride Selenium hexafluoride Tellurium hexafluoride fluorosilane Nitrosyl fluoride Fluorine nitrate Hydrogen sulfide Ammonia Helium Hydrogen iodide Krypton Nitrogen dinitrogen oxide Neon Nitrogen oxide; and Xenon 3. The dielectric gaseous compound according to claim 2,

wherein said dielectric gaseous compound is at least one compound selected from the group consisting of Argon Trifluoroborane Hydrogen bromide

20 Jun. 12, 2008

Bromopentafluoroethane Chlorotrifluoroethene Trifluoroacetonitrile trifluoromethyl isocyanate trifluoromethyl thiocarbonyl fluoride Trifluormethylthiocarbonylfluorid (germ.) pentafluoro-nitroso-ethane//Pentafluor-nitroso-aethan (trifluoromethyl-carbonyl)-difluoro-amine Hexafluoroethane Bis-trifluorimethyl-nitroxid bis-trifluoromethyl ether bis(trifluoromethyl)tellurium bis(trifluoromethyl)ditelluride N,N-Difluor-pentafluoraethylamin (germ.) N-Fluor-bis(trifluormethyl)-amin (germ.) N-Fluor-N-trifluorimethoxy-perfluormethylamin (germ.) fluoroformyl cyanide 1-chloro-1-fluoro-ethene/71-Chlor-1-fluor-aethen/71

chloro-1-fluoroethylene 1,1-Difluoroethene itrans-1,2-difluoro-ethene/#trans-vinylene difluoride/

(E)-1,2-difluoroethylene/7(E)-1,2-difluoro-ethene/ itrans-vinylene fluoride

1,2-difluoro-ethene/icis-vinylene luor-aethen//vinylene fluoride

icis-1,2-difluoro-ethene//icis-Vinylene difluoride//(Z)- 1,2-difluoroethylene/(Z)-1,2-difluoro-ethene/icis vinylene fluoride

1,1,1,2-Tetrafluoroethane 1,1,2,2-Tetrafluoroethane Fluoroethene 1,1,1-Trifluoroethane Ether, methyl trifluoromethyl Ethene 1,1-Difluoroethane Fluoroethane Ethane fluoro-dimethyl-borane Disiloxane, 1,1,3,3-tetrafluoro-1,3-dimethyl-Trifluoroet

hene trifluoroacetaldehyde?/Trifluor-acetaldehyd Pentafluoroethane Difluoromethyl trifluoromethyl ether Tris(trifluoromethyl)bismuth tetrafluoropropadiene/tetrafluoro-allene?/1,1,3,3-tet

rafluoro-1,2-propadiene tetrafluorocyclopropene Perfluoropropionyliodid pentafluoro-propionitrile?/pentafluoropropiononitrile hexafluoro-cyclopropane?/Hexafluor-cyclopropan//freon

HCl216 Hexafluoropropylene hexafluoro-1,3dioxolane Octafluoropropane Perfluormethylethylether 1,1-difluoro-propadiene/allenylidene difluoride?/1,1-dif

luoro-allene 2,3,3,3-tetrafluoro-propene/HFO-1234yf trans. HFO-1234ze 3,3,3-Trifluoropropene cyclopropene Allene 1,1-difluoro-propene/propenylidene difluoride?/1,1-Dif

luor-propen

difluoride?/1,2-Dif

US 2008/O 135817 A1 21

methylketene 2-fluoropropene 1-Propene DL-2-aminopropanoic acid 3,3,3-trifluoro-propyne/3.3.3-Trifluor-propin/trifluo

romethyl-ethyne/3,3,3-trifluoro-1-propyne 1,1,3,3,3-pentafluoro-propenef/1.1.3.3.3-Pentafluor-pro pen

1,2,3,3,3-pentafluoro-propene 1.1.1.4.4.4-hexafluoro-2-butyne 1,1,4,4-tetrafluoro-butane-2,3-dione Trifluormethylhypochlorit Chlor-difluor-methyl-hypofluorit N-Chlor-N-fluor-trifluorimethylamin (germ.) Chlordifluordifluoraminomethan thiocarbonyl difluoride Thiocarbonyldifluorid (germ.) selenocarbonyl difluoride Trifluoroiodomethane N-Fluor-difluorimethanimin (germ.) trifluoro-nitroso-methane?/Trifluor-nitroso-methan difluoro-carbamoyl fluoride trifluoro-nitro-methane/Trifluor-nitro-methan//fluoropi

crin Tetrafluoromethane Tetrafluorformamidin (germ.) tetrafluorourea hypofluorous acid trifluoromethyl ester//Hypofluorigsae

ure-trifluormethylester//trifluoromethyl hypofluorite trifluoromethanesulfonyl fluoride N,N-Difluor-trifluorimethylamin (germ.) Trifluormethyloxydifluoramin (Difluoraminoxy)difluorimethylhypofluorit sulfurcyanide pentafluoride Schwefelcyanid-pentafluorid (germ.) difluoro-trifluoromethyl-phosphine Hexafluorimethandiamin perfluoro methylsilane Perfluorimethylsilan (germ.) Trifluormethyl-tetrafluorphosphoran (germ.) Difluoromethane Fluoroiodomethane fluoromethane/methyl fluoride/Fluor-methan//freon-41 trifluoromethyl-silane” CF3SiH3 methyltrifluorosilane difluoro-methyl-silane fluoro-methyl-silane methyl germane Difluorformimin Trifluoromethane trifluoromethane thiol Trifluormethanthiol (germ.) N.N.,1,1-Tetrafluormethylamin difluoro dichlorosilane Difluordichlorsilan (germ.) difluoro chlorosilane Difluorchlorsilan (germ.) Phosphorus chloride difluoride Chlorotrifluorosilane Hydrogen chloride Chlorosilane Carbon monoxide Carbon dioxide Carbonyl sulfide

Jun. 12, 2008

Difluoramine trans-Difluorodiazine cis-Difluorodiazine Thionyl fluoride Trifluorosilane Nitrogen trifluoride Trifluoramine oxide thiazyl trifluoride Phosphorus trifluoride Germanium(IV) fluoride Tetrafluorosilane Phosphorus pentafluoride Selenium hexafluoride Tellurium hexafluoride fluorosilane Nitrosyl fluoride Fluorine nitrate Hydrogen sulfide Ammonia Helium Hydrogen iodide Krypton Nitrogen Nitrous oxide Neon Nitrogen oxide; and Xenon 4. The dielectric gaseous compound according to claim 1,

further comprising forming an azeotrope of said dielectric gaseous compound.

5. The dielectric gaseous compound according to claim 1, further comprising admixing said dielectric gaseous com pound with at least one gas selected from the group consisting of nitrogen, CO and N.O.

6. An insulation-gas for use in electrical equipment, wherein said insulation-gas is a dielectric gaseous compound which exhibits the following properties:

a boiling point in the range between about -20°C. to about -273° C.;

low non-oZone depleting: a GWP less than about 22,200; chemical stability, as measured by a negative standard

enthalpy of formation (dHf-0); a toxicity level such that when the dielectric gas leaks, the

effective diluted concentration does not exceed its PEL; and

a dielectric strength greater than air. 7. The insulation-gas according to claim 6, wherein said

dielectric gaseous compound is at least one compound selected from the group consisting of:

Arsenic pentafluoride Arsine Diboron tetrafluoride Diborane Perchloric acid, 2-chloro-1,1,2,2-tetrafluoroethyl ester

(9CI) Perchloric acid, 1.2.2-trichloro-1,2-difluoroethyl ester Trifluoroacetyl chloride trifluoromethylisocyanide (CF3-NC) trifluoromethyl isocyanide trifluoro-nitroso-ethene?/Trifluor-nitroso-aethen Tetrafluoroethene 3,3,4,4-tetrafluoro-3,4-dihydro-1,2diazete (Difluoramino)difluoracetonitril

US 2008/O 135817 A1 Jun. 12, 2008 22

Tetrafluorooxirane Bis(fluoroxy)difluormethan Trifluoroacetyl fluoride Trifluormethyl-phosphonylfluorid Perfluorimethylfluorformiat Cyanogen fluoride trifluoro-acetyl hypofluorite Trifluorimethylphosphane (germ.) perfluoro-2-aza-1-propene Diazomethane Perfluor-2-aza-1-propen (germ.) formaldehyde/Formalin N-Fluor-tetrafluor-1-aethanimin (germ.) (methyl)difluoroborane 3.3-difluoro-2-trifluoromethyl-oxaziridine (Methyl)difluorboran (germ.) bis-trifluoromethyl-diazene/hexafluoro-icis- Chloromethane

aZomethane methylphosphonous acid difluoride/difluoro-methyl Fluoroxypentafluoroethane phosphine bis-trifluoromethyl peroxide trifluoro-methoxy-silane 1,1-Bis(fluoroxy)tetrafluoroaethan Methylhypofluorid Hexafluorodimethyl sulfide Methane 3-fluoro-3HH-diazirine-3-carbonitrile Methylsilane Ethyne #Si-bromo-it-Sili Si'-methanediyl-bis-silane 1,2,2-trifluoro-aziridine #Si-iodo-it-Sili Si'-methanediyl-bis-silane Ketene Difluormethylnitrit (difluoro)vinylboran trifluoromethanol (Difluor) vinylboran (germ.) Formyl fluoride trifluoro-vinyl-silane Cyanic acid Ethinylsilan Chlorine ethyl-difluor-borane Chlorine fluoride Ethyl-difluor-boran (germ.) Chlorine trioxide fluoride methyl-methylen-amine carbon oxide selenide/Kohlenoxidselenid Dimethyl ether Fluorine vinyl-silane Difluorosilane Dimethylsilane Fluorine oxide Chloroethyne fluorine peroxide fluoroethyne/fluoro-acetylene Sulfinuryl fluoride Ethanedinitrile sulphur difluoride tetrafluoropropyne/1,3,3,3-tetrafluoropropyne Phosphorus trifluoride oxide hexafluoro-oxetane Phosphorus trifluoride sulfide Trifluoro(trifluoromethyl)oxirane tetrafluorophosphorane 1,1,1,3,3,3-Hexafluoropropanone Tetrafluorohydrazine pentafluoro-propionyl fluoride/perfluoropropionyl fluo- Sulfur tetrafluoride

ride hexafluoro disiloxane Trifluoromethyl trifluorovinyl ether Hexafluordisiloxan (germ.) 1-Propyne Nitryl fluoride Cyclopropane Hydrogen Propane Hydrogen selenide Trimethylborane Phosphorus trihydride cyanoketene Germanium hydride butatriene Silane Cyano-bispentafluorethyl-phosphin Tin tetrahydride Trimethyl-1,1,2,2-tetrafluorethylsilan Oxygen methyl diborane OZone Methyldiboran (germ.) Antimony monophosphide carbonyl bromide fluoride Disilicon monophosphide chloro-difluoro-nitroso-methane?/Chlor-difluor-nitroso- Radon methan Argon

chloroperoxytrifluoromethane Trifluoroborane carbonylchlorid-fluorid Hydrogen bromide Carbonychlorid fluorid (germ.) Bromopentafluoroethane 3,3-difluoro-3HH-diazirine Chlorotrifluoroethene difluoro diazomethane Trifluoroacetonitrile Difluordiazomethan (germ.) trifluoromethyl isocyanate Carbonyl fluoride trifluoromethyl thiocarbonyl fluoride Difluordioxiran Trifluormethylthiocarbonylfluorid (germ.) difluoro-(3-fluoro-3#H!-diazirin-3-yl)-amine pentafluoro-nitroso-ethane//Pentafluor-nitroso-aethan trifluoromethylazide (trifluoromethyl-carbonyl)-difluoro-amine Trifluormethylazid (germ.) Hexafluoroethane tetrafluoro-diaziridine Bis-trifluorimethyl-nitroxid Fluorperoxytrifluorimethan bis-trifluoromethyl ether

US 2008/O 135817 A1 23

bis(trifluoromethyl)tellurium bis(trifluoromethyl)ditelluride N,N-Difluor-pentafluoraethylamin (germ.) N-Fluor-bis(trifluorimethyl)-amin (germ.) N-Fluor-N-trifluornethoxy-perfluorimethylamin (germ.) fluoroformyl cyanide 1-chloro-1-fluoro-ethene/71-Chlor-1-fluor-aethen/71

chloro-1-fluoroethylene 1,1-Difluoroethene itrans-1,2-difluoro-ethene/#trans-vinylene difluoride/

(E)-1,2-difluoroethylene/7(E)-1,2-difluoro-ethene/ itrans-vinylene fluoride

1,2-difluoro-ethene//icis-Vinylene luor-aethen//vinylene fluoride

icis-1,2-difluoro-ethene/icis-Vinylene difluoride//(Z)- 1,2-difluoroethylene/(Z)-1,2-difluoro-ethene/icis vinylene fluoride

1,1,1,2-Tetrafluoroethane 1,1,2,2-Tetrafluoroethane Fluoroethene 1,1,1-Trifluoroethane Ether, methyl trifluoromethyl Ethene 1,1-Difluoroethane Fluoroethane Ethane fluoro-dimethyl-borane Disiloxane, 1,1,3,3-tetrafluoro-1,3-dimethyl-Trifluoroet hene

trifluoroacetaldehyde?/Trifluor-acetaldehyd Pentafluoroethane Difluoromethyl trifluoromethyl ether Tris(trifluoromethyl)bismuth tetrafluoropropadiene/tetrafluoro-allene?/1,1,3,3-tet

rafluoro-1,2-propadiene tetrafluorocyclopropene Perfluoropropionyliodid pentafluoro-propionitrile?/pentafluoropropiononitrile

hexafluoro-cyclopropane?/Hexafluor-cyclopropan// freon-HCl216

Hexafluoropropylene hexafluoro-1,3dioxolane Octafluoropropane Perfluormethylethylether 1,1-difluoro-propadiene/allenylidene difluoride?/1,1-dif

luoro-allene 2,3,3,3-tetrafluoro-propene/HFO-1234yf trans. HFO-1234ze 3,3,3-Trifluoropropene cyclopropene Allene 1,1-difluoro-propene/propenylidene difluoride?/1,1-Dif

luor-propen methylketene 2-fluoropropene 1-Propene DL-2-aminopropanoic acid 3,3,3-trifluoro-propyne/3.3.3-Trifluor-propin/trifluo

romethyl-ethyne/3,3,3-trifluoro-1-propyne 1,1,3,3,3-pentafluoro-propenef/1.1.3.3.3-Pentafluor-pro pen

1,2,3,3,3-pentafluoro-propene 1.1.1.4.4.4-hexafluoro-2-butyne 1,1,4,4-tetrafluoro-butane-2,3-dione Trifluormethylhypochlorit

difluoride?/1,2-Dif

Jun. 12, 2008

Chlor-difluor-methyl-hypofluorit N-Chlor-N-fluor-trifluorimethylamin (germ.) Chlordifluordifluoraminomethan thiocarbonyl difluoride Thiocarbonyldifluorid (germ.) selenocarbonyl difluoride Trifluoroiodomethane N-Fluor-difluorimethanimin (germ.) trifluoro-nitroso-methane/Trifluor-nitroso-methan difluoro-carbamoyl fluoride trifluoro-nitro-methane/Trifluor-nitro-methan//fluoropi

crin Tetrafluoromethane Tetrafluorformamidin (germ.) tetrafluorourea hypofluorous acid trifluoromethyl ester//Hypofluorigsae

ure-trifluormethylester//trifluoromethyl hypofluorite trifluoromethanesulfonyl fluoride N,N-Difluor-trifluorimethylamin (germ.) Trifluormethyloxydifluoramin (Difluoraminoxy)difluorimethylhypofluorit sulfurcyanide pentafluoride Schwefelcyanid-pentafluorid (germ.) difluoro-trifluoromethyl-phosphine Hexafluormethandiamin perfluoro methylsilane Perfluorimethylsilan (germ.) Trifluormethyl-tetrafluorphosphoran (germ.) Difluoromethane Fluoroiodomethane fluoromethane/methyl fluoride/Fluor-methan//freon-41 trifluoromethyl-silane” CF3SiH3 methyltrifluorosilane difluoro-methyl-silane fluoro-methyl-silane methylgermane Difluorformimin Trifluoromethane trifluoromethane thiol Trifluormethanthiol (germ.) N.N.,1,1-Tetrafluorimethylamin difluoro dichlorosilane Difluordichlorsilan (germ.) difluoro chlorosilane Difluorchlorsilan (germ.) Phosphorus chloride difluoride Chlorotrifluorosilane Hydrogen chloride Chlorosilane Carbon monoxide Carbon dioxide Carbonyl sulfide Difluoramine trans-Difluorodiazine cis-Difluorodiazine Thionyl fluoride Trifluorosilane Nitrogen trifluoride Trifluoramine oxide thiazyl trifluoride Phosphorus trifluoride Germanium(IV) fluoride Tetrafluorosilane Phosphorus pentafluoride

US 2008/O 135817 A1 24

Selenium hexafluoride Tellurium hexafluoride fluorosilane Nitrosyl fluoride Fluorine nitrate Hydrogen sulfide Ammonia Helium Hydrogen iodide Krypton Nitrogen dinitrogen oxide Neon Nitrogen oxide; and Xenon 8. The insulation-gas according to claim 7, wherein said

dielectric gaseous compound is at least one compound selected from the group consisting of: Argon Trifluoroborane Hydrogen bromide Bromopentafluoroethane Chlorotrifluoroethene Trifluoroacetonitrile trifluoromethyl isocyanate trifluoromethylthiocarbonyl fluoride Trifluormethylthiocarbonylfluorid (germ.) pentafluoro-nitroso-ethane//Pentafluor-nitroso-aethan (trifluoromethyl-carbonyl)-difluoro-amine Hexafluoroethane Bis-trifluormethyl-nitroxid bis-trifluoromethyl ether bis(trifluoromethyl)tellurium bis(trifluoromethyl)ditelluride N,N-Difluor-pentafluoraethylamin (germ.) N-Fluor-bis(trifluorimethyl)-amin (germ.) N-Fluor-N-trifluorimethoxy-perfluormethylamin (germ.) fluoroformyl cyanide 1-chloro-1-fluoro-ethene/71-Chlor-1-fluor-aethen/71

chloro-1-fluoroethylene 1,1-Difluoroethene itrans-1,2-difluoro-ethene/#trans-vinylene difluoride/

(E)-1,2-difluoroethylene/7(E)-1,2-difluoro-ethene/ itrans-vinylene fluoride

1,2-difluoro-ethene//icis-Vinylene luor-aethen//vinylene fluoride

icis-1,2-difluoro-ethene/icis-Vinylene difluoride//(Z)- 1,2-difluoroethylene/(Z)-1,2-difluoro-ethene/icis vinylene fluoride

1,1,1,2-Tetrafluoroethane 1,1,2,2-Tetrafluoroethane Fluoroethene 1,1,1-Trifluoroethane Ether, methyl trifluoromethyl Ethene 1,1-Difluoroethane Fluoroethane Ethane fluoro-dimethyl-borane Disiloxane, 1,1,3,3-tetrafluoro-1,3-dimethyl-Trifluoroet hene

trifluoroacetaldehyde?/Trifluor-acetaldehyd Pentafluoroethane Difluoromethyl trifluoromethyl ether

difluoride?/1,2-Dif

Jun. 12, 2008

Tris(trifluoromethyl)bismuth tetrafluoropropadiene/tetrafluoro-allene?/1,1,3,3-tet

rafluoro-1,2-propadiene tetrafluorocyclopropene Perfluoropropionyliodid pentafluoro-propionitrile?/pentafluoropropiononitrile hexafluoro-cyclopropane?/Hexafluor-cyclopropan//freon

HCl216 Hexafluoropropylene hexafluoro-1,3dioxolane Octafluoropropane Perfluormethylethylether 1,1-difluoro-propadiene/allenylidene difluoride?/1,1-dif

luoro-allene 2,3,3,3-tetrafluoro-propene/HFO-1234yf trans. HFO-1234ze 3,3,3-Trifluoropropene cyclopropene Allene 1,1-difluoro-propene/propenylidene difluoride?/1,1-Dif

luor-propen methylketene 2-fluoropropene 1-Propene DL-2-aminopropanoic acid 3,3,3-trifluoro-propyne/3.3.3-Trifluor-propin/trifluorom

ethyl-ethyne/3,3,3-trifluoro-1-propyne 1,1,3,3,3-pentafluoro-propene/1,1,3,3,3-Pentafluor-pro pen

1.2.3,3,3-pentafluoro-propene 1.1.1.4.4.4-hexafluoro-2-butyne 1,1,4,4-tetrafluoro-butane-2,3-dione Trifluormethylhypochlorit Chlor-difluor-methyl-hypofluorit N-Chlor-N-fluor-trifluorimethylamin (germ.) Chlordifluordifluoraminomethan thiocarbonyl difluoride Thiocarbonyldifluorid (germ.) selenocarbonyl difluoride Trifluoroiodomethane N-Fluor-difluorimethanimin (germ.) trifluoro-nitroso-methane/Trifluor-nitroso-methan difluoro-carbamoyl fluoride trifluoro-nitro-methane/Trifluor-nitro-methan//fluoropi

crin Tetrafluoromethane Tetrafluorformamidin (germ.) tetrafluorourea hypofluorous acid trifluoromethyl ester//Hypofluorigsae

ure-trifluormethylester//trifluoromethyl hypofluorite trifluoromethanesulfonyl fluoride N,N-Difluor-trifluorimethylamin (germ.) Trifluormethyloxydifluoramin (Difluoraminoxy)difluorimethylhypofluorit sulfurcyanide pentafluoride Schwefelcyanid-pentafluorid (germ.) difluoro-trifluoromethyl-phosphine Hexafluormethandiamin perfluoro methylsilane Perfluorimethylsilan (germ.) Trifluormethyl-tetrafluorphosphoran (germ.) Difluoromethane Fluoroiodomethane fluoromethane/methyl fluoride/Fluor-methan//freon-41

US 2008/O 135817 A1

trifluoromethyl-silane” CF3SiH3 methyltrifluorosilane difluoro-methyl-silane fluoro-methyl-silane methylgermane Difluorformimin Trifluoromethane trifluoromethane thiol Trifluormethanthiol (germ.) N.N.,1,1-Tetrafluormethylamin difluoro dichlorosilane Difluordichlorsilan (germ.) difluoro chlorosilane Difluorchlorsilan (germ.) Phosphorus chloride difluoride Chlorotrifluorosilane Hydrogen chloride Chlorosilane Carbon monoxide Carbon dioxide Carbonyl sulfide Difluoramine trans-Difluorodiazine cis-Difluorodiazine Thionyl fluoride Trifluorosilane Nitrogen trifluoride Trifluoramine oxide thiazyl trifluoride Phosphorus trifluoride Germanium(IV) fluoride

25 Jun. 12, 2008

Tetrafluorosilane Phosphorus pentafluoride Selenium hexafluoride Tellurium hexafluoride fluorosilane Nitrosyl fluoride Fluorine nitrate Hydrogen sulfide Ammonia Helium Hydrogen iodide Krypton Nitrogen Nitrous oxide Neon Nitrogen oxide; and Xenon 9. The insulation-gas according to claim 6, further com

prising forming an azeotrope of said dielectric gaseous com pound.

10. The insulation-gas according to claim 6, further com prising admixing said dielectric gaseous compound with at least one gas selected from the group consisting of nitrogen, CO and N.O.

11. The insulation-gas according to claim 6, wherein said electrical equipment is at least one selected from the group consisting of gas-insulated circuit breakers and current-in terruption equipment, gas-insulated transmission lines, gas insulated transformers, and gas-insulated substations.

c c c c c