CA1044004A - Polypropylene film capacitor - Google Patents
Polypropylene film capacitorInfo
- Publication number
- CA1044004A CA1044004A CA200,994A CA200994A CA1044004A CA 1044004 A CA1044004 A CA 1044004A CA 200994 A CA200994 A CA 200994A CA 1044004 A CA1044004 A CA 1044004A
- Authority
- CA
- Canada
- Prior art keywords
- polypropylene film
- film capacitor
- insulating oil
- oil
- oxygen
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 239000003990 capacitor Substances 0.000 title claims abstract description 38
- 239000004743 Polypropylene Substances 0.000 title claims abstract description 35
- -1 Polypropylene Polymers 0.000 title claims abstract description 32
- 229920001155 polypropylene Polymers 0.000 title claims abstract description 30
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 18
- 239000001301 oxygen Substances 0.000 claims abstract description 18
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 18
- 150000001875 compounds Chemical class 0.000 claims abstract description 10
- 239000003921 oil Substances 0.000 claims description 58
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 claims description 16
- 150000002148 esters Chemical class 0.000 claims description 8
- 239000002253 acid Substances 0.000 claims description 6
- 239000003989 dielectric material Substances 0.000 claims description 4
- 239000003925 fat Substances 0.000 claims description 4
- 229930185605 Bisphenol Natural products 0.000 claims description 2
- BRLQWZUYTZBJKN-UHFFFAOYSA-N Epichlorohydrin Chemical compound ClCC1CO1 BRLQWZUYTZBJKN-UHFFFAOYSA-N 0.000 claims description 2
- 239000004593 Epoxy Chemical class 0.000 claims description 2
- 150000007513 acids Chemical class 0.000 claims description 2
- 125000002723 alicyclic group Chemical group 0.000 claims description 2
- 125000001931 aliphatic group Chemical group 0.000 claims description 2
- 125000005907 alkyl ester group Chemical group 0.000 claims description 2
- IISBACLAFKSPIT-UHFFFAOYSA-N bisphenol A Chemical compound C=1C=C(O)C=CC=1C(C)(C)C1=CC=C(O)C=C1 IISBACLAFKSPIT-UHFFFAOYSA-N 0.000 claims description 2
- 125000000113 cyclohexyl group Chemical class [H]C1([H])C([H])([H])C([H])([H])C([H])(*)C([H])([H])C1([H])[H] 0.000 claims description 2
- 239000003822 epoxy resin Substances 0.000 claims description 2
- LNEPOXFFQSENCJ-UHFFFAOYSA-N haloperidol Chemical compound C1CC(O)(C=2C=CC(Cl)=CC=2)CCN1CCCC(=O)C1=CC=C(F)C=C1 LNEPOXFFQSENCJ-UHFFFAOYSA-N 0.000 claims description 2
- 150000002576 ketones Chemical class 0.000 claims description 2
- 150000002895 organic esters Chemical class 0.000 claims description 2
- 150000003014 phosphoric acid esters Chemical class 0.000 claims description 2
- 229920000647 polyepoxide Polymers 0.000 claims description 2
- 229920005989 resin Polymers 0.000 claims description 2
- 239000011347 resin Substances 0.000 claims description 2
- 235000010469 Glycine max Nutrition 0.000 description 10
- 244000068988 Glycine max Species 0.000 description 10
- 230000006866 deterioration Effects 0.000 description 8
- 230000015556 catabolic process Effects 0.000 description 6
- 150000002430 hydrocarbons Chemical class 0.000 description 6
- 230000003647 oxidation Effects 0.000 description 5
- 238000007254 oxidation reaction Methods 0.000 description 5
- MQIUGAXCHLFZKX-UHFFFAOYSA-N Di-n-octyl phthalate Natural products CCCCCCCCOC(=O)C1=CC=CC=C1C(=O)OCCCCCCCC MQIUGAXCHLFZKX-UHFFFAOYSA-N 0.000 description 4
- BJQHLKABXJIVAM-UHFFFAOYSA-N bis(2-ethylhexyl) phthalate Chemical compound CCCCC(CC)COC(=O)C1=CC=CC=C1C(=O)OCC(CC)CCCC BJQHLKABXJIVAM-UHFFFAOYSA-N 0.000 description 4
- 239000004215 Carbon black (E152) Substances 0.000 description 3
- 150000004996 alkyl benzenes Chemical class 0.000 description 3
- 125000006267 biphenyl group Chemical group 0.000 description 3
- 238000010276 construction Methods 0.000 description 3
- 229930195733 hydrocarbon Natural products 0.000 description 3
- 238000010348 incorporation Methods 0.000 description 3
- ZUOUZKKEUPVFJK-UHFFFAOYSA-N diphenyl Chemical group C1=CC=CC=C1C1=CC=CC=C1 ZUOUZKKEUPVFJK-UHFFFAOYSA-N 0.000 description 2
- 125000001033 ether group Chemical group 0.000 description 2
- 239000002480 mineral oil Substances 0.000 description 2
- 235000010446 mineral oil Nutrition 0.000 description 2
- 230000002265 prevention Effects 0.000 description 2
- GGMPTLAAIUQMIE-UHFFFAOYSA-N 2,3,4,5,6-pentachlorobiphenyl Chemical compound ClC1=C(Cl)C(Cl)=C(Cl)C(Cl)=C1C1=CC=CC=C1 GGMPTLAAIUQMIE-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 101100409194 Rattus norvegicus Ppargc1b gene Proteins 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 159000000032 aromatic acids Chemical class 0.000 description 1
- 235000010290 biphenyl Nutrition 0.000 description 1
- 239000004305 biphenyl Substances 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 230000002844 continuous effect Effects 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- USIUVYZYUHIAEV-UHFFFAOYSA-N diphenyl ether Natural products C=1C=CC=CC=1OC1=CC=CC=C1 USIUVYZYUHIAEV-UHFFFAOYSA-N 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 125000004185 ester group Chemical group 0.000 description 1
- 239000011888 foil Substances 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229960003903 oxygen Drugs 0.000 description 1
- 229920001083 polybutene Polymers 0.000 description 1
- 230000003334 potential effect Effects 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
- H01G4/00—Fixed capacitors; Processes of their manufacture
- H01G4/002—Details
- H01G4/018—Dielectrics
- H01G4/20—Dielectrics using combinations of dielectrics from more than one of groups H01G4/02 - H01G4/06
- H01G4/22—Dielectrics using combinations of dielectrics from more than one of groups H01G4/02 - H01G4/06 impregnated
- H01G4/221—Dielectrics using combinations of dielectrics from more than one of groups H01G4/02 - H01G4/06 impregnated characterised by the composition of the impregnant
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Organic Insulating Materials (AREA)
- Fixed Capacitors And Capacitor Manufacturing Machines (AREA)
- Lubricants (AREA)
- Compositions Of Macromolecular Compounds (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A polypropylene film capacitor impregnated with an oxygen-containing insulating oil into which an epoxidized compound is incorporated.
A polypropylene film capacitor impregnated with an oxygen-containing insulating oil into which an epoxidized compound is incorporated.
Description
The present invention relates to a capacitor which uses as a dielectric material a polypropylene film impregnated with an insulating oil and which is improved in its efficiency.
Recently, for the preparation of polypropylene film capacitors impregnated with insulating oils, hydrocarbon insula-ting oils such as mineral oil, polybutene, alkylbenzene, alkyl-naphthalene, diallylalkane, etc. have been used in place of chlorinated biphenyl such as diphenyl trichloride, diphenyl pen-tachloride, etc. These hydrocarbon insulating oils have small polarity and hence they are relatively excellent in dielectric characteristic. However, their dielectric constant, which deter-mines the dimensions of a capacitor, is small and at most 40 -50% of the chlorinated diphenyl. Therefore, the composite dielectric constant of the capacitor also becomes smaller and correspondingly it requires more constituting materials for the same capacity than capacitors impregnated with chlorinated diphenyl.
Furthermore, the dielectric constant of said hydrocarbon insulating oils is almost the same as that of polypropylene, so that when a capacitor is constructed using said insulating oils, approximately equal voltages are applied to the insulating oil and polypropylene and this is a great burden for the insulating oil.
In this connection, the dielectric breakdown voltage of said insulating oils is at most 25 - 50 V/~ and that of polypropy- -lene is 300 - 400 V/~. Thus dielectric breakdown of the insula-ting oils predominates in dielectric breakdown of capacitor.
In order to overcome the defects of said insulating oils as mentioned above, it is desired to impregnate the poly-propylene film with insulating oils having higher dielectricconstant.
- 1 - ,~
~t i . . . . . ` . . . .
, .. . ... ~ ... -; , ., . ; ' ~Q4~q~
However, it is difficult to obtain pure hydrocarbon compounds comprising only carbon and hydrogen such as said insul- -ating oils which have a high dielectric constant.
Ester type or ether type insulating oils have relatively high dielectric constant, but these insulating oils contain oxygen and cause deterioration of polypropylene ~ilm due to oxi-dation.
That is, deterioration of polypropylene in insulating -oil naturally depends greatly upon the amount of oxygen in the insulating oil. -Furthermore, when such ester or ether insulating oils are used for a polypropylene film capacitor, local decomposition of the insulating oils occurs due to electric stress in the electric field.
Especially in the case of a capacitor such as a self-healing capacitor which recovers insulation by partial breakdown, said phenomenon is conspicuous. At this time, oxygen in ester or ether group possessed by the insulating oils is released to oxidize polypropylene to cause a reduction in the life of the capacitor. - ~-As a result of the inventors' research on prevention of oxidation of polypropylene in an attempt to utilize the merit of the high dielectric constant of said oxygen-containing insu- ~
lating oils, it has been found that incorporation of epoxidized `
compound into the insulating oils is very effective.
Thus according to the present invention there is pro-vided, in a polypropylene film capacitor impregnated with an oxy-gen-containing insulating oil and having polypropylene film as a dielectric material, the improvement that an epoxidized com-pound is incorporated into said insulating oil.
.
Recently, for the preparation of polypropylene film capacitors impregnated with insulating oils, hydrocarbon insula-ting oils such as mineral oil, polybutene, alkylbenzene, alkyl-naphthalene, diallylalkane, etc. have been used in place of chlorinated biphenyl such as diphenyl trichloride, diphenyl pen-tachloride, etc. These hydrocarbon insulating oils have small polarity and hence they are relatively excellent in dielectric characteristic. However, their dielectric constant, which deter-mines the dimensions of a capacitor, is small and at most 40 -50% of the chlorinated diphenyl. Therefore, the composite dielectric constant of the capacitor also becomes smaller and correspondingly it requires more constituting materials for the same capacity than capacitors impregnated with chlorinated diphenyl.
Furthermore, the dielectric constant of said hydrocarbon insulating oils is almost the same as that of polypropylene, so that when a capacitor is constructed using said insulating oils, approximately equal voltages are applied to the insulating oil and polypropylene and this is a great burden for the insulating oil.
In this connection, the dielectric breakdown voltage of said insulating oils is at most 25 - 50 V/~ and that of polypropy- -lene is 300 - 400 V/~. Thus dielectric breakdown of the insula-ting oils predominates in dielectric breakdown of capacitor.
In order to overcome the defects of said insulating oils as mentioned above, it is desired to impregnate the poly-propylene film with insulating oils having higher dielectricconstant.
- 1 - ,~
~t i . . . . . ` . . . .
, .. . ... ~ ... -; , ., . ; ' ~Q4~q~
However, it is difficult to obtain pure hydrocarbon compounds comprising only carbon and hydrogen such as said insul- -ating oils which have a high dielectric constant.
Ester type or ether type insulating oils have relatively high dielectric constant, but these insulating oils contain oxygen and cause deterioration of polypropylene ~ilm due to oxi-dation.
That is, deterioration of polypropylene in insulating -oil naturally depends greatly upon the amount of oxygen in the insulating oil. -Furthermore, when such ester or ether insulating oils are used for a polypropylene film capacitor, local decomposition of the insulating oils occurs due to electric stress in the electric field.
Especially in the case of a capacitor such as a self-healing capacitor which recovers insulation by partial breakdown, said phenomenon is conspicuous. At this time, oxygen in ester or ether group possessed by the insulating oils is released to oxidize polypropylene to cause a reduction in the life of the capacitor. - ~-As a result of the inventors' research on prevention of oxidation of polypropylene in an attempt to utilize the merit of the high dielectric constant of said oxygen-containing insu- ~
lating oils, it has been found that incorporation of epoxidized `
compound into the insulating oils is very effective.
Thus according to the present invention there is pro-vided, in a polypropylene film capacitor impregnated with an oxy-gen-containing insulating oil and having polypropylene film as a dielectric material, the improvement that an epoxidized com-pound is incorporated into said insulating oil.
.
2 -Examples of the epoxidized compounds used in the pre-sent invention are epoxy resins which are combined products of epichlorohydrin and bisphenol, epo~idized products of fats and oils, natural fats and oils, alkyl esters of resin acids, epoxy derivatives of cyclohexane, etc.
Examples of the oxygen-containing insulating oils are organic esters such as aromatic acid esters, alicyclic acid esters, aliphatic acid esters, phosphoric acid esters, etc., ether oils, ketone type oils, etc.
The amount of the epoxidized compound has no special limitation, but preferably is about 0.1 - 10~ by weight of the insulating oil.
The invention will be further understood from the foll-owing description by way of example of embodiments thereof with reference to the accompanying drawings. ~n the following the term "remaining perc~ntage" is used to mean the percentage of the number of capacitors which were not broken and remained among those which were subjected to applied voltage. In the drawings:
Figure 1 is a graph which shows the relation between the amount (volu~e ratio) of oxygen in insulating oil and the number of days required for complete deterioration of polypropyl-ene film.
Figure 2 is a cross-sectional view of one embodiment of a capacitor according to the present invention.
Figures 3 - 6 are graphs which show remaining percentage of capacitors as shown in Figure 2 upon application of an alter-nating voltage.
Figure 1 shows the relation between the amount of oxygen present in insulating oil and the time required for com-plete deterioration of a polypropylene film in the insulating oilat a temperature of 95 C. It is clear from E'igure 1 that the 1~3 ~, ., -,. . .
~49~
deterioration time decreases with increase in the amount of oxygen.
The following Examples illustrate the present invention.
Example 1 As a representative ester insulating oil, dioctyl phtha-late was used. One percent by weight of epoxidized soya-bean oil was incorporated into said insulating oil. This insulating oil was impregnated in self-healing polypr~pylene film capacitors having the construction as shown in Figure 2 wherein 1 is a metal-lized paper which was obtained by vapor-depositing a metal on both surfaces of an insulating paper and which had the same poten-tial at both surfaces and 2 is polypropylene film.
Figure 3 shows changes of remaining percentage of self-healing polypropylene film capacitors a which were impregna-ted with dioctyl phthalate into which the epoxidized soya-bean `
oil was incorporated and self-healing polypropylene film capaci-tors b which were impregnated with only dioctyl phthalate under ~ `
continuous application of alternating voltage at 85C. `
As is clear from Figure 3, the remaining percentage of the capacitors b impregnated with only dioctyl phthalate was extremely low and complete dielectric breakdown was caused in a short period.
On the other hand, the capacitors a impregnated with ~ -dioctyl phthalate containing the epoxidized soya-bean oil showed no breakdown and exhibited a remaining percentage of 100% after `
1000 hours.
The above results show that the epoxidized soya-bean oil captured oxygen generated from ester group by application of voltage to prevent oxidation and deterioration of the polypropyl-ene film.
_ ~ _ :
., ~., ;
~C~4~
Example 2 As a representative ether insulating oil, alkyldiphenyl ether was used. Into said ether was incorporated 1% by weight of epoxidized soya-bean oil. This ~as impregnated in self-healing polypropylene film capacitors having the construction as shown in Figure 2.
Figure 4 shows the changes in the remaining percentages of capacitors a impregnated with alkyldiphenyl ether containing epoxidized soya-bean oil and capacitors b impregnated with alkyl diphenyl ether containing no epoxidized soya-bean oil under con-tinuous application of alternating voltage at 85C.
As is clear from Figure 4, the results are similar to those in Example 1. That is, deterioration of polypropylene caused by oxygen freed from ether group by application of voltage was prevented by the incorporation of the epoxidized soya-bean oil.
In this connection, the same tests as those in Examples 1 and 2 were made on self-healing polypropylene film capacitors impregnated with mineral oil and alkyl benzene which are pure hydrocarbon compounds containing no oxygen. The results are shown in Figures 5 and 6. As is clear from Figures 5 and 6, both capa-citors a impregnated with insulating oil containing epoxidized soya-bean oil and capacitors b impregnated with only insulating oil showed high remaining percentages. It is considered that these results were obtained because oxygen generated by electric stress is not present in the pure hydrocarbon compounds such as alkyl benzene and alkylnaphthalene and deterioration of polypro-pylene due to oxidation occurs with difficulty.
As explained above, it has been found that incorporation of an epoxidized compound into polypropylene film capacitors impregnated with oxygen-containing insulating oil is extremely effective for prevention of oxidation of the polypropylene.
~'1 ,.
44Q(~
In the above Examples, epoxidized soya-bean oil was used, but other epoxidized compounds may be used to obtain similar results. Furthermore, any capacitors having polypropylene film as a dielectric material may be used regardless of whether they are of the self-healing type or of the non-self-healing type, such as aluminum foil capacitors.
As explained hereinbefore, the polypropylene film capa-citor of the present invention is improved in efficiency.
All of the capacitors a and b used in the above Examples have the constructions as shown in Figure 2.
~' . :
, .
'.'''' '`
.';"'. "':
' ' :
'"'`:' . ~
" '' ' , .
.~ ., .
~,~i ' .
Examples of the oxygen-containing insulating oils are organic esters such as aromatic acid esters, alicyclic acid esters, aliphatic acid esters, phosphoric acid esters, etc., ether oils, ketone type oils, etc.
The amount of the epoxidized compound has no special limitation, but preferably is about 0.1 - 10~ by weight of the insulating oil.
The invention will be further understood from the foll-owing description by way of example of embodiments thereof with reference to the accompanying drawings. ~n the following the term "remaining perc~ntage" is used to mean the percentage of the number of capacitors which were not broken and remained among those which were subjected to applied voltage. In the drawings:
Figure 1 is a graph which shows the relation between the amount (volu~e ratio) of oxygen in insulating oil and the number of days required for complete deterioration of polypropyl-ene film.
Figure 2 is a cross-sectional view of one embodiment of a capacitor according to the present invention.
Figures 3 - 6 are graphs which show remaining percentage of capacitors as shown in Figure 2 upon application of an alter-nating voltage.
Figure 1 shows the relation between the amount of oxygen present in insulating oil and the time required for com-plete deterioration of a polypropylene film in the insulating oilat a temperature of 95 C. It is clear from E'igure 1 that the 1~3 ~, ., -,. . .
~49~
deterioration time decreases with increase in the amount of oxygen.
The following Examples illustrate the present invention.
Example 1 As a representative ester insulating oil, dioctyl phtha-late was used. One percent by weight of epoxidized soya-bean oil was incorporated into said insulating oil. This insulating oil was impregnated in self-healing polypr~pylene film capacitors having the construction as shown in Figure 2 wherein 1 is a metal-lized paper which was obtained by vapor-depositing a metal on both surfaces of an insulating paper and which had the same poten-tial at both surfaces and 2 is polypropylene film.
Figure 3 shows changes of remaining percentage of self-healing polypropylene film capacitors a which were impregna-ted with dioctyl phthalate into which the epoxidized soya-bean `
oil was incorporated and self-healing polypropylene film capaci-tors b which were impregnated with only dioctyl phthalate under ~ `
continuous application of alternating voltage at 85C. `
As is clear from Figure 3, the remaining percentage of the capacitors b impregnated with only dioctyl phthalate was extremely low and complete dielectric breakdown was caused in a short period.
On the other hand, the capacitors a impregnated with ~ -dioctyl phthalate containing the epoxidized soya-bean oil showed no breakdown and exhibited a remaining percentage of 100% after `
1000 hours.
The above results show that the epoxidized soya-bean oil captured oxygen generated from ester group by application of voltage to prevent oxidation and deterioration of the polypropyl-ene film.
_ ~ _ :
., ~., ;
~C~4~
Example 2 As a representative ether insulating oil, alkyldiphenyl ether was used. Into said ether was incorporated 1% by weight of epoxidized soya-bean oil. This ~as impregnated in self-healing polypropylene film capacitors having the construction as shown in Figure 2.
Figure 4 shows the changes in the remaining percentages of capacitors a impregnated with alkyldiphenyl ether containing epoxidized soya-bean oil and capacitors b impregnated with alkyl diphenyl ether containing no epoxidized soya-bean oil under con-tinuous application of alternating voltage at 85C.
As is clear from Figure 4, the results are similar to those in Example 1. That is, deterioration of polypropylene caused by oxygen freed from ether group by application of voltage was prevented by the incorporation of the epoxidized soya-bean oil.
In this connection, the same tests as those in Examples 1 and 2 were made on self-healing polypropylene film capacitors impregnated with mineral oil and alkyl benzene which are pure hydrocarbon compounds containing no oxygen. The results are shown in Figures 5 and 6. As is clear from Figures 5 and 6, both capa-citors a impregnated with insulating oil containing epoxidized soya-bean oil and capacitors b impregnated with only insulating oil showed high remaining percentages. It is considered that these results were obtained because oxygen generated by electric stress is not present in the pure hydrocarbon compounds such as alkyl benzene and alkylnaphthalene and deterioration of polypro-pylene due to oxidation occurs with difficulty.
As explained above, it has been found that incorporation of an epoxidized compound into polypropylene film capacitors impregnated with oxygen-containing insulating oil is extremely effective for prevention of oxidation of the polypropylene.
~'1 ,.
44Q(~
In the above Examples, epoxidized soya-bean oil was used, but other epoxidized compounds may be used to obtain similar results. Furthermore, any capacitors having polypropylene film as a dielectric material may be used regardless of whether they are of the self-healing type or of the non-self-healing type, such as aluminum foil capacitors.
As explained hereinbefore, the polypropylene film capa-citor of the present invention is improved in efficiency.
All of the capacitors a and b used in the above Examples have the constructions as shown in Figure 2.
~' . :
, .
'.'''' '`
.';"'. "':
' ' :
'"'`:' . ~
" '' ' , .
.~ ., .
~,~i ' .
Claims (5)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. In a polypropylene film capacitor impregnated with an oxygen-containing insulating oil and having polypropylene film as a dielectric material, the improvement that an epoxidized com-pound is incorporated into said insulating oil.
2. A polypropylene film capacitor according to claim 1, wherein the epoxidized compound is selected from epoxy resins which are combined products of epichlorohydrin and bisphenol, epoxidized products of fats and oils, natural fats and oils, alkyl esters of resin acids, and epoxy derivatives of cyclohexane.
3. A polypropylene film capacitor according to claim 1, wherein the oxygen-containing insulating oil is an organic ester, an ether oil, or a ketone type oil.
4. A polypropylene film capacitor according to claim 3, wherein the oxygen-containing insulating oil is an aromatic acid ester, an alicyclic acid ester, an aliphatic acid ester, or a phosphoric acid ester.
5. A polypropylene film capacitor according to claim 1, 2 or 3, wherein the amount of the epoxidized compound is in the range 0.1 - 10% by weight of the insulating oil.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP48062232A JPS5213623B2 (en) | 1973-06-01 | 1973-06-01 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1044004A true CA1044004A (en) | 1978-12-12 |
Family
ID=13194193
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA200,994A Expired CA1044004A (en) | 1973-06-01 | 1974-05-28 | Polypropylene film capacitor |
Country Status (4)
| Country | Link |
|---|---|
| JP (1) | JPS5213623B2 (en) |
| CA (1) | CA1044004A (en) |
| DE (1) | DE2426577C2 (en) |
| FR (1) | FR2232056A1 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6030834B2 (en) * | 1977-02-28 | 1985-07-18 | 文化シヤツタ−株式会社 | Manufacturing method of reinforcing plate |
| JPS56134838U (en) * | 1980-03-14 | 1981-10-13 | ||
| JPS60143926A (en) * | 1983-12-30 | 1985-07-30 | Nippon Petrochem Co Ltd | Method and apparatus for forming rugged sheet |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL163048C (en) * | 1965-11-18 | 1980-07-15 | Gen Electric | METHOD FOR MANUFACTURING AN ELECTRIC CAPACITOR. |
| DE1564711B2 (en) * | 1966-09-16 | 1973-02-15 | Siemens AG, 1000 Berlin u 8000 München | REGENERATIVE ELECTRIC CAPACITOR |
| DE1589549C3 (en) * | 1967-10-18 | 1978-04-27 | Robert Bosch Gmbh, 7000 Stuttgart | Electric alternating voltage capacitor with a dielectric containing plastic tapes |
| GB1252159A (en) * | 1967-12-11 | 1971-11-03 | ||
| DE1924331A1 (en) * | 1969-05-13 | 1970-11-19 | Bosch Gmbh Robert | Drinking agent with castor oil for self-healing capacitors |
| DE2047477C3 (en) * | 1969-09-29 | 1981-09-17 | General Electric Co., Schenectady, N.Y. | Method of making a thin polypropylene film and its use in a capacitor |
| JPS492463A (en) * | 1972-04-18 | 1974-01-10 |
-
1973
- 1973-06-01 JP JP48062232A patent/JPS5213623B2/ja not_active Expired
-
1974
- 1974-05-28 CA CA200,994A patent/CA1044004A/en not_active Expired
- 1974-05-31 DE DE19742426577 patent/DE2426577C2/en not_active Expired
- 1974-05-31 FR FR7419006A patent/FR2232056A1/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5018963A (en) | 1975-02-27 |
| DE2426577A1 (en) | 1974-12-12 |
| FR2232056A1 (en) | 1974-12-27 |
| JPS5213623B2 (en) | 1977-04-15 |
| FR2232056B3 (en) | 1977-04-08 |
| DE2426577C2 (en) | 1986-01-02 |
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