US4542246A
Expired / Lapsed
US
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Electrical insulating oil having high oxidation stability and method for production thereof
Assignee: Eneos Corp
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Filing: 1983-03-25
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Granted: 1985-09-17
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Expires: 2003-03-25
Abstract
Abstract An electrical insulating oil, comprising: a base oil selected from the group consisting of a mineral oil, an alkylbenzene, and a mixture of a mineral oil and an alkylbenzene; a non-basic nitrogen content in an amount of 16 ppm or more; and a basic nitrogen content in an amount of 6% or less based on the weight of the non-basic nitrogen content.
Inventors
- 👤 Atsushi Matsunaga
- 👤 Sampo Kusayanagi
- 👤 Masamitu Takano
- 👤 Yutaka Kato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 05:24
CPC Classifications
H; H01; H01B; H01B3/00; H01B3/18; H01B3/20; H01B3/22
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
35 words
An oxidation stability-improving agent for an electrial insulating oil comprising a concentrate separated from mineral oil and containing as main components: non-basic nitrogen compounds and sulfide-type sulfur compounds, and substantially not containing basic nitrogen compounds.
Claim 2
Dependent Claim
35 words
An oxidation stability-improving agent for an electrial insulating oil comprising a concentrate separated from mineral oil and containing as main components: non-basic nitrogen compounds and sulfide-type sulfur compounds, and substantially not containing basic nitrogen compounds.
Claim 3
Dependent Claim
30 words
An agent as claimed in claim 1, wherein said mineral oil is a lubricating fraction of a crude oil obtained by hydrogenation refining of said fraction under a mild condition.
Claim 4
Dependent Claim
88 words
An agent as claimed in claim 1, wherein said agent is obtained by the process comprising (a) subjecting a mineral oil to clay-adsorption refining to remove therefrom basic nitrogen compounds; (b) subjecting the resulting oil of step (a) to a percolation treatment by passing it through a layer comprising at least one member of the group consisting of solid silica gel, alumina and fluorisil; (c) elution treating said layer with a polar organic solvent; and (d) distilling off the solvent in the eluate under an inert gas atmosphere.
Claim 5
Dependent Claim
39 words
An agent as claimed in claim 1, wherein said agent has a non-basic nitrogen content of 1 to 4 wt%, a sulfide-type sulphur content of 2 to 5 wt%, and a basic nitrogen content of 5 ppm or less.
Claim 6
Independent Claim
168 words
A method for improving the oxygen stability of an electrical insulating oil, comprising adding (a) an oxygen stability-improving agent for an electrical insulating oil comprising a concentrate separated from a mineral oil and containing as main components: non-basic nitrogen compounds and sulfide-type sulfur compounds, and substantially not containing basic nitrogen compounds; to (b) a member selected from the group consisting of a refined mineral oil having a viscosity of 4 to 30 cSt at 40° C., an alkylbenzene, and a mixed oil of a refined mineral oil having a viscosity of 4 to 30 cSt at 40° C. and an alkylbenzene, to thereby increase the non-basic nitrogen content and the sulfide-type sulfur content in the resulting oil and thus maintain (i) the non-basic nitrogen content in the resulting oil at 16 to 260 ppm, (ii) the sulfide-type sulfur content in the resulting oil at 50 to 2,000 ppm, and (iii) the basic nitrogen content in the resulting oil at 6% or less based on the non-basic nitrogen content.
Claim 7
Independent Claim
168 words
A method for improving the oxygen stability of an electrical insulating oil, comprising adding (a) an oxygen stability-improving agent for an electrical insulating oil comprising a concentrate separated from a mineral oil and containing as main components: non-basic nitrogen compounds and sulfide-type sulfur compounds, and substantially not containing basic nitrogen compounds; to (b) a member selected from the group consisting of a refined mineral oil having a viscosity of 4 to 30 cSt at 40° C., an alkylbenzene, and a mixed oil of a refined mineral oil having a viscosity of 4 to 30 cSt at 40° C. and an alkylbenzene, to thereby increase the non-basic nitrogen content and the sulfide-type sulfur content in the resulting oil and thus maintain (i) the non-basic nitrogen content in the resulting oil at 16 to 260 ppm, (ii) the sulfide-type sulfur content in the resulting oil at 50 to 2,000 ppm, and (iii) the basic nitrogen content in the resulting oil at 6% or less based on the non-basic nitrogen content.
Claim 8
Dependent Claim
55 words
A method as claimed in claim 5, wherein the resulting oil is maintained such that the non-basic nitrogen content is 25 to 230 ppm, the sulfide-type sulfur content is 60 to 2000 ppm, and that the basic nitrogen content is 6% or less based on the non-basic nitrogen content but does not exceed 3 ppm.
Claim 9
Dependent Claim
54 words
A method as claimed in claim 6, wherein the resulting oil is maintained such that then non-basic nitrogen content is 25 to 100 ppm, the sulfide-type sulfur content is 100 to 1000 ppm, and the basic nitrogen content is 6% or less based on the non-basic nitrogen content but does not exceed 3 ppm.
Claim 10
Dependent Claim
48 words
A method as claimed in claim 5, wherein said refined mineral oil, alkylbenzene, mixed oil, or electrical insulating oil has a basic nitrogen content of 2 ppm or less, a non-basic nitrogen content of 10 ppm or less, and a total sulfur content of 0.05 wt% or less.
Claim 11
Dependent Claim
33 words
A method as claimed in claim 5, wherein the oil is controlled in terms of acid numbers obtained by the test for oxidation stability prescribed by JIS C-2101 at 0.1 mg-KOH/g or less.
References Cited (Backward Citations)
US3759817A
Cited
US3551324A
Cited
US3586752A
Cited
US3904507A
Cited
US3932267A
Cited
US4069165A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-09-16 | 1989-03-18 | 1989-09-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-09-16 | 1993-03-18 | 1993-09-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-09-16 | 1997-03-18 | 1997-09-17 | $7700.00 | Window Closed / Lapsed |