US3872582A - Process for making a voltage dependent resistor - Google Patents

Process for making a voltage dependent resistor Download PDF

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Publication number
US3872582A
US3872582A US428737A US42873773A US3872582A US 3872582 A US3872582 A US 3872582A US 428737 A US428737 A US 428737A US 42873773 A US42873773 A US 42873773A US 3872582 A US3872582 A US 3872582A
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United States
Prior art keywords
oxide
mole percent
bi2o3
bismuth oxide
bismuth
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Expired - Lifetime
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US428737A
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English (en)
Inventor
Michio Matsuoka
Gen Itakura
Atsushi Iga
Takeshi Masuyama
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Panasonic Holdings Corp
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Matsushita Electric Industrial Co Ltd
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Priority claimed from JP733619A external-priority patent/JPS5240038B2/ja
Priority claimed from JP733610A external-priority patent/JPS5310678B2/ja
Priority claimed from JP4248873A external-priority patent/JPS5318277B2/ja
Priority claimed from JP6806673A external-priority patent/JPS5311079B2/ja
Application filed by Matsushita Electric Industrial Co Ltd filed Critical Matsushita Electric Industrial Co Ltd
Priority to US518944A priority Critical patent/US3905006A/en
Application granted granted Critical
Publication of US3872582A publication Critical patent/US3872582A/en
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01C—RESISTORS
    • H01C7/00—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material
    • H01C7/10—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material voltage responsive, i.e. varistors
    • H01C7/102—Varistor boundary, e.g. surface layers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
    • H01B1/06—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors mainly consisting of other non-metallic substances
    • H01B1/08—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors mainly consisting of other non-metallic substances oxides
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01C—RESISTORS
    • H01C17/00—Apparatus or processes specially adapted for manufacturing resistors
    • H01C17/02—Apparatus or processes specially adapted for manufacturing resistors adapted for manufacturing resistors with envelope or housing
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making
    • Y10T29/49082—Resistor making
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making
    • Y10T29/49082—Resistor making
    • Y10T29/49101—Applying terminal

Definitions

  • ABSTRACT A process for making a voltage dependent resistor which has a zinc oxide sintered body which itself has voltage dependent properties. The process is made up of the steps of: (1) providing a formed body of a powder mixture having as a major part zinc oxide and additive; (2) coating on the side surfaces of the formed body a paste having as the solid ingredient composition at least one member selected from the group of a) more than 50 mole of-silicon dioxide (SiO and less than 50 mole of bismuth oxide (Bi O b) the same composition as that of said additive, c) more than mole percent of antimony oxide (Sb O and less than 70 mole percent of bismuth oxide (Bi- 0 and d) more than mole percent of indium oxide (1n O and less than 50 mole percent of bismuth oxide (Bi O (3) sintering the coated body; and (4) applying electrodes to opposite surfaces of the sintered body.
  • This invention relates to the preparation of a voltage dependent resistor the properties of which are due to the bulk thereof, and more particularly to a varistor comprising a zinc oxide sintered body having a high resistance layer of a composition such as silicon dioxide, antimony oxide or indium oxide on the side surface of the sintered body.
  • n (V/C)" where V is the voltage across the resistor, I is the current flowing through the resistor, C is a constant corresponding to the voltage at a given current and exponent n is a numerical value greater than 1. The value of n is calculated by the following equation:
  • silicon carbide varistors have non-linearity due to the contacts among individual grains of silicon carbide bonded together by a ceramic binding material i.e. to the bulk and are controlled with respect to the C-value by changing the dimension in the direction in which the current flows through the varistors.
  • the silicon carbide varistors however, have a relatively low n-value ranging from 3 t0. 9am! are answe xfit painanqm wzimatme:
  • a disadvantage of the zinc oxide voltage-dependent resistors is their poor stability in an electric load life test in a high ambient humidity.
  • the sintered body shows a decrease in the surface electrical resistance. This decrease causes in particular an increase in the leakage current in the zinc oxide voltage-dependent resistor of the bulk type and results in a poor non-linear property.
  • the deterioration of the non-linear property of the voltage-dependent resistor occurs even at a load of low power such as a load lower than 0.01 watt in a high ambient humidity, for example 90 percent R.H at C. Therefore, it is necessary that the sintered body is completely protected against outside moisture by a protective coating.
  • Another disadvantage of the zinc oxide voltage dependent resistors aforesaid exists in their poor ability to withstand impulse current.
  • the sintered body suffers a flashover along its side surface at an impulse voltage above SOOV/mm, and despite no deterioration in the interior of sintered body the side surface of the sintered body is heavily damaged.
  • the poor ability to withstand impulse current is unfavorable particu larly for application of the varistor as a lightning arrester,
  • a voltage dependent resistor comprising a sintered body comprising zinc oxide and other additives and being characterized by a high C-value, high n-value, high stability with respect to temperature, humidity and electric load, and good ability to withstand impulse current.
  • a resistor is disclosed in U.S. Pat. No. 3,760,318. More specifically, a zinc oxide sintered body according to said U.S. Pat. No. 3,760,318 has Li ions or Na ions diffused into said sintered body from the side surface thereof at a temperature of 600C to l0O0C. This diffusing process inevitably results in lowering the n-value of the resultant resistor in the current region lower than 10 uA. The low n-value in such low current region is undesirable for an application requiring low leakage current.
  • An object of the present invention is to provide a method for making a voltage dependent resistor characterized by a high stability with respect to a dc. load in high humidity and a good ability to withstand impulse current.
  • Another object of the present invention is to provide a method for making a voltage dependent resistor characterized by a high n-value even in a low current region and a high stability with respect to a dc. load in high humidity and a good ability to withstand impulse current.
  • FIGURE is a partly cross-sectional view of a voltage-dependent resistor in accordance with the invention.
  • reference character 10 designates, as a whole, a voltage-dependent resistor comprising, as its active element, a sintered body having surfaces consisting of a side surface 2 and opposite end surfaces 3 and 4 to which a pair of electrodes 5 and 6 are applied.
  • Said sintered body 1 is prepared in a manner hereinafter set forth and has a high resistance layer 11 at said side surface 2 and can have any crosssectional form such as circular, square or rectangular.
  • the process for making a voltage dependent resistor of a bulk type characterized by a high humidity resistance and a good ability to withstand current surges comprises: (1 providing a formed body of a powder mixture comprising, as a major part, zinc oxide, and an additive including BiO (2) coating on the side surfaces of said body a paste comprising, solid ingredient composition, at least one member selected from the group consisting of a more than 50 mole percent of silicon dioxide (SiO and less than 50 mole percent of bismuth oxide (Bi O b) the same composition as that of said addition, c) more than 30 mole percent of antimony oxide (Sb O and less than 70 mole percent of bismuth oxide (Bi O and d) more than 50 mole percent of indium oxide (In O and less than 50 mole percent of bismuth oxide (Bi O (3) sintering said coated body; and (4) applying two electrodes to the opposite end surfaces of said sintered body.
  • a paste comprising, solid ingredient composition, at least one member selected from the group consisting of
  • Said zinc oxide sintered body which itself has voltage dependent properties can be prepared by using a composition described in U.S. Pat. Nos. 3,663,458, 3,669,058, 3,636,529, 3,632,528, 3,634,337 and 3,598,763.
  • compositions consisting essentially of, as a major part, 80.0 to 99.9 mole percent of zinc oxide and, as an additive, 0.05 to 10.0 mole percent of bismuth oxide (Bi O and 0.05 to 10.0 mole percent, in total, of at least one member selected from the group consisting of cobalt oxide (C), manganese oxide (MnO), antimony oxide (Sb O barium oxide (BaO), strontium oxide (SrO) and lead oxide (PbO).
  • C cobalt oxide
  • MnO manganese oxide
  • strontium oxide SrO
  • PbO lead oxide
  • the resultant resistor has an excellent ability to withstand current surges in an impulse current test, when said coating paste comprises, as the solid composition, 70 to 95 mole percent of silicon dioxide (SiO and 30 to mole percent of bismuth oxide (Bi O ).
  • the ability to withstand surge current can be improved greatly by using coating paste comprising, as the solid ingredient composition, 70 to 95 mole percent of antimony oxide (Sb O and 30 to 5 mole percent of bismuth oxide 2 3)-
  • the ability to withstand surge current can be further improved by using coating paste comprising, as the solid ingredient composition, 50 to 95 mole percent of silicon dioxide (SiO 2 to 45 mole percent of antimony oxide (Sb O and 2 to mole percent of bismuth oxide (Bi O It has been discovered according to the invention that the DC.
  • said powder mixture consists essentially of, asa major part, 99.9 to 80.0 mole percent of zinc oxide (ZnO) and, as an additive, 0.05 to 10.0 mole percent of bismuth oxide (Bi O and 0.05 to [0.0 mole percent, in total, of at least one member selected from the group consisting of cobalt oxide (C00), manganese oxide (MnO) antimony oxide (Sb- 0 barium oxide (BaO), strontium oxide (SrO) and lead oxide (PbO).
  • ZnO zinc oxide
  • Bi O bismuth oxide
  • PbO lead oxide
  • the sintered body 1 can be prepared by a per se well known ceramic technique.
  • the starting materials comprising zinc oxide powder and additives such as bismuth oxide, cobalt oxide, manganese oxide, antimony oxide, barium oxide, strontium oxide, lead oxide, uranium oxide and tin oxide are mixed in a wet mill so as to produce a homogeneous mixture.
  • the mixtures are dried and pressed in a mold into desired shapes at a pressure from 100 kg/cm' to 1000 kg/cm
  • the mixed slurry can be fabricated into the desired shape by extruding and then dried.
  • the mixtures may be preliminarily calcined at a temprature of 700 to 1000C and pulverized for easy fabrication in the subsequent pressing step.
  • the mixtures may be admixed with a suitable binder such as water, polyvinyl alcohol, etc.
  • the formed bodies are coated, on the side surfaces, with a paste including powder having the same composition as said additive, or a combination of bismuth oxide with silicon dioxide, antimony oxide or indium oxide, so as to form a high resistance layer at the side surfaces after sintering.
  • Said paste comprises, as the solid ingredient composition, at least one member selected from the group consisting of a more than 50 mole percent of silicon dioxide (SiO and less than 50 mole percent of bismuth oxide (Bi O b) the same composition as that of said additive, c) more than 30 mole percent of antimony oxide (Sb O and less than mole percent of bismuth oxide (Bi O and d) more than 50 mole percent of indium oxide (In O and less than 50 mole percent of bismuth oxide (Bi O and, as a binding material, an organic resin such as epoxy, vinyl or phenol resin in an organic solvent such as butyl acetate, toluene or the like.
  • Said silicon dioxide, bismuth oxide, antimony oxide and indium oxide can be replaced, respectively, with any silicon compound, bismuth compound, antimony compound and indium compound such as an oxalate, carbonate, nitrate, sulfate, iodide, fluoride or hydroxide which is converted into the corresponding oxide at the sintering temperature.
  • the formed bodies After being coated with said paste, the formed bodies are sintered in air at a temperature of 1000 to l450C for 1 to 5 hours, and then furnace-cooled to room temperature.
  • the sintering temperature is determined based on the desired electrical resistivity, nonlinearity stability and the thickness of the high resistance layer formed at the side surface of the sintered body. Also, the electrical resistivity can be reduced by airquenching from the sintering temperature to room temperature.
  • the sintered body has non-ohmic resistance due to the bulkitself. Therefore, its C-value can be changed without impairing the n-value by changing the distance between said opposite end surfaces. A shorter distance results in a lower C-value.
  • the coating paste forms a high resistance layer, as can be proved by measurement of the resistance distribution in the crosssection of the sintered body, which will show a high resistance at the side surface of the sintered body.
  • the high resistance layer is controlled so as to have a thickness more than 10p.
  • the paste comprising a combination of silicon dioxide and bismuth oxide, or antimony oxide and bismuth oxide forms a layer having a thickness of more than 3 1. and that said layer comprises, in a region electrolytic plating of Ag, Cu, Ni, Sn etc. vacuum evaporating of Al, Zn, Sn etc. and flame spraying of Cu, Sn, Al, Zn etc. in accordance with the prior well known techniques.
  • Lead wires can be attached to the electrodes in a per se conventional manner by using conventional solder. It is convenient to employ a conductive adhesive comprising silver powder and resin in an organic solvent in order to connect the lead wires to the silver electrodes.
  • the n-value of a voltage-dependent resistor according to this invention does not deteriorate even in a low current region due to the introduction of the covering layer at the side surface of the sintered body, and it has a high stability with respect to temperature and humidity and in the load life test, which is carried out at 70C, 90 percent RH at a rating power for 500 hours. The nvalue and C-value do not change appreciably after the load life test. From a surge test, which is carried out by applying a 4X 10 p.sec impulse current twice, it is shown that this voltage-dependent resistor has the ability to withstand surges of more than 2000A/cm EXAMPLE 1.
  • the bodies were dried. Then, the bodies were sintered in air for 5 hours at 1200C and furnace-cooled.
  • the sintered bodies were lapped to the thickness listed in table 1 by lapping the opposite end surfaces thereof with silicon carbide abrasive having a particle size of 600 mesh.
  • the opposite end surfaces of the sintered discs were provided with a spray metallized film of aluminum by a per se well known technique.
  • the electric characteristics of the resultant resistors are, shown in Table 1. It will be readily understood that the C-value changes in proportion to the thickness of the sintered body.
  • Thickness of high resistive layer 30a
  • EXAMPLEZ EXAMPLE 3
  • Table 3 Starting materials of Table 3 were fabricated into voltage dependent resistors by the same process as that of Example 1. Then the tests were carried out by the same methods as those of Example 2. The electric characteristics of the resultant resistors are shown in Table 3.
  • Example 5 The fabrication process and testing method were the same as those of Example 2 and the thickness of the high resistance layer was varied with the results as shown in Table 4. It is easily understood that the ability to withstand impulses increases with an increase in the thickness of the high resistance layer and the rate of change of the C-value caused by the boiling test decreases with an increase of thickness of the high resis- ,1 EXAMPLE 5
  • Starting materials of Table 5 were fabricated into voltage dependent resistors by the same process as in Example 1.
  • the pressed bodies were sintered at a temperature between 1000C to 1450C for 5 hours after covering the side surface with coating pastes as listed in Table 5.
  • the test conditions were the same as those of Example 2.
  • the electric characteristics of resulting tame y resistors are shown in Table 5.
  • Table 6 Contlnued Composition of Sintcred body Solid Ingredient Sinten'ng Electric Characteristics of (mol. 70) of Paste Temp. Resultant Resistor lm ulse Boiling Further C (V) n Wit stand Test ZnO Bi O Additives (moi. (C) (at lmA) 0.1-lmA (KA) AC (70) 97.0 0.5 MnO 0.5 MnO 1200 2600 50 60 0.5
  • a process for making a voltage dependent resistor comprised of a zinc oxide sintered body which itself has voltage dependent properties comprising: (1) providing a formed body of powder mixture comprising, as a major part, zinc oxide and the remainder being an additive; (2) coating on the side surface of said body a paste having a solid ingredient composition of at least one member selected from the group consisting of a) more than 50 mole percent of silicon dioxide (SiO and less than 50 mole percent of bismuth oxide (Bi O b) the same composition as that-of said additive, c) more than mole percent of antimony oxide (Sb O- and less than 70 mole percent of bismuth oxide (Bi O- and d) more than 50 mole percent of indium oxide (ln O and less than 50 mole percent of bismuth oxide (Bi O (3) sintering said coated body; and (4) applying two electrodes to the opposite end surfaces of said sintered body.
  • the coating paste has a solid in gredient composition of 70 to 95 mole percent ofsilicon dioxide (SiO and 30 to 5 mole percent of bismuth oxide (Bi O 3.
  • the coating paste has a solid ingredient composition of to mole percent of antimony oxide (Sb O and 30 to 5 mole percent of bismuth oxide (Bi O 4.
  • the coating paste has a solid ingredient composition of 50 to 95 mole percent of silicon dioxide (SiO 2 to 45 mole percent of antimony oxide (Sb O and 2 to 20 mole percent of bismuth oxide (B50 5.
  • a process according'to claim 1 which said powder mixture consists essentially of, as a major part, 99.9 to 80.0 mole percent of zinc oxide (ZnO) and, as an additive, 0.05 to 10.0 mole percent of bismuth oxide (Bi O and 0.05 to 10.0 mole percent of at least one member selected from the group consisting of cobalt oxide (C00), manganese oxide (MnO) antimony oxide (Sb O barium oxide (BaO), strontium oxide (SrO) and lead oxide (PbO).

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  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Manufacturing & Machinery (AREA)
  • Thermistors And Varistors (AREA)
  • Compositions Of Oxide Ceramics (AREA)
US428737A 1972-12-29 1973-12-27 Process for making a voltage dependent resistor Expired - Lifetime US3872582A (en)

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Application Number Priority Date Filing Date Title
US518944A US3905006A (en) 1972-12-29 1974-10-29 Voltage dependent resistor

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP733619A JPS5240038B2 (enrdf_load_stackoverflow) 1972-12-29 1972-12-29
JP733610A JPS5310678B2 (enrdf_load_stackoverflow) 1972-12-29 1972-12-29
JP4248873A JPS5318277B2 (enrdf_load_stackoverflow) 1973-04-13 1973-04-13
JP6806673A JPS5311079B2 (enrdf_load_stackoverflow) 1973-06-15 1973-06-15

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US (1) US3872582A (enrdf_load_stackoverflow)
CA (1) CA1017072A (enrdf_load_stackoverflow)
DE (1) DE2365232B2 (enrdf_load_stackoverflow)
FR (1) FR2212620B1 (enrdf_load_stackoverflow)
GB (1) GB1453310A (enrdf_load_stackoverflow)
IT (1) IT1002565B (enrdf_load_stackoverflow)
NL (1) NL179524C (enrdf_load_stackoverflow)

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4031498A (en) * 1974-10-26 1977-06-21 Kabushiki Kaisha Meidensha Non-linear voltage-dependent resistor
US4042535A (en) * 1975-09-25 1977-08-16 General Electric Company Metal oxide varistor with improved electrical properties
US4052340A (en) * 1974-11-13 1977-10-04 U.S. Philips Corporation Method for producing a voltage dependent resistor and a voltage dependent resistor obtained therewith
DE3026200A1 (de) * 1979-07-13 1981-01-15 Hitachi Ltd Nichtlinearer widerstand und verfahren zu seiner herstellung
US4326187A (en) * 1979-10-08 1982-04-20 Hitachi, Ltd. Voltage non-linear resistor
US4349855A (en) * 1978-03-18 1982-09-14 Mitsubishi Denki Kabushiki Kaisha Lightning arrester
US4559167A (en) * 1983-12-22 1985-12-17 Bbc Brown, Boveri & Company, Limited Zinc oxide varistor
US4700169A (en) * 1984-03-29 1987-10-13 Kabushiki Kaisha Toshiba Zinc oxide varistor and method of making it
US5053739A (en) * 1989-12-15 1991-10-01 Electric Power Research Institute Very high energy absorbing varistor
US5075666A (en) * 1989-12-15 1991-12-24 Electric Power Research Institute Varistor composition for high energy absorption
US5455554A (en) * 1993-09-27 1995-10-03 Cooper Industries, Inc. Insulating coating
US5817130A (en) * 1996-05-03 1998-10-06 Sulzer Intermedics Inc. Implantable cardiac cardioverter/defibrillator with EMI suppression filter with independent ground connection
US20020133936A1 (en) * 2001-03-20 2002-09-26 Ragnar Osterlund Method of manufacturing a metal-oxide varistor with improved energy absorption capability
US20040046636A1 (en) * 1998-09-11 2004-03-11 Murata Manufacturing Co., Ltd. Method of producing ceramic thermistor chips
US20050195065A1 (en) * 1999-10-04 2005-09-08 Toshiya Imai Nonlinear resistor and method of manufacturing the same
CN101311364B (zh) * 2008-03-10 2010-12-15 中国科学院长春光学精密机械与物理研究所 制备p型氧化锌半导体体材料的方法
US20200299109A1 (en) * 2019-03-24 2020-09-24 Nilec Solutions, Llc Apparatus, system and method for the delivery of items onto surfaces including elevated surfaces

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Publication number Priority date Publication date Assignee Title
CH601135A5 (enrdf_load_stackoverflow) * 1976-07-01 1978-06-30 Bbc Brown Boveri & Cie
DE2639042C3 (de) * 1976-08-30 1982-03-25 Matsushita Electric Industrial Co., Ltd., Kadoma, Osaka Spannungsabhängiges Widerstandselement und Verfahren zu dessen Herstellung
SE455143B (sv) * 1980-03-19 1988-06-20 Meidensha Electric Mfg Co Ltd Sett att framstella en icke-linjer, spenningsberoende resistor
DE3917570A1 (de) * 1989-05-30 1990-12-06 Siemens Ag Elektrisches keramisches bauelement, insbesondere kaltleiter, mit hoher elektrischer ueberschlagsfestigkeit im elektrodenfreien bereich und verfahren zu seiner herstellung
SE466826B (sv) * 1990-06-28 1992-04-06 Asea Brown Boveri Saett att framstaella en metalloxidvaristor med foerbaettrad energihaallfasthet

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US3632528A (en) * 1968-10-22 1972-01-04 Matsushita Electric Ind Co Ltd Lead-modified zinc oxide voltage variable resistor
US3663458A (en) * 1967-10-09 1972-05-16 Matsushita Electric Ind Co Ltd Nonlinear resistors of bulk type
US3760318A (en) * 1971-08-27 1973-09-18 Matsushita Electric Ind Co Ltd Process for making a voltage dependent resistor
US3764566A (en) * 1972-03-24 1973-10-09 Matsushita Electric Ind Co Ltd Voltage nonlinear resistors
US3778743A (en) * 1973-02-23 1973-12-11 Matsushita Electric Ind Co Ltd Voltage-nonlinear resistors

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US3496512A (en) * 1966-05-16 1970-02-17 Matsushita Electric Ind Co Ltd Non-linear resistors
US3663458A (en) * 1967-10-09 1972-05-16 Matsushita Electric Ind Co Ltd Nonlinear resistors of bulk type
US3503029A (en) * 1968-04-19 1970-03-24 Matsushita Electric Ind Co Ltd Non-linear resistor
US3632528A (en) * 1968-10-22 1972-01-04 Matsushita Electric Ind Co Ltd Lead-modified zinc oxide voltage variable resistor
US3760318A (en) * 1971-08-27 1973-09-18 Matsushita Electric Ind Co Ltd Process for making a voltage dependent resistor
US3764566A (en) * 1972-03-24 1973-10-09 Matsushita Electric Ind Co Ltd Voltage nonlinear resistors
US3778743A (en) * 1973-02-23 1973-12-11 Matsushita Electric Ind Co Ltd Voltage-nonlinear resistors

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4031498A (en) * 1974-10-26 1977-06-21 Kabushiki Kaisha Meidensha Non-linear voltage-dependent resistor
US4052340A (en) * 1974-11-13 1977-10-04 U.S. Philips Corporation Method for producing a voltage dependent resistor and a voltage dependent resistor obtained therewith
US4042535A (en) * 1975-09-25 1977-08-16 General Electric Company Metal oxide varistor with improved electrical properties
US4349855A (en) * 1978-03-18 1982-09-14 Mitsubishi Denki Kabushiki Kaisha Lightning arrester
DE3026200A1 (de) * 1979-07-13 1981-01-15 Hitachi Ltd Nichtlinearer widerstand und verfahren zu seiner herstellung
US4326187A (en) * 1979-10-08 1982-04-20 Hitachi, Ltd. Voltage non-linear resistor
US4559167A (en) * 1983-12-22 1985-12-17 Bbc Brown, Boveri & Company, Limited Zinc oxide varistor
US4700169A (en) * 1984-03-29 1987-10-13 Kabushiki Kaisha Toshiba Zinc oxide varistor and method of making it
US5053739A (en) * 1989-12-15 1991-10-01 Electric Power Research Institute Very high energy absorbing varistor
US5075666A (en) * 1989-12-15 1991-12-24 Electric Power Research Institute Varistor composition for high energy absorption
US5455554A (en) * 1993-09-27 1995-10-03 Cooper Industries, Inc. Insulating coating
US5817130A (en) * 1996-05-03 1998-10-06 Sulzer Intermedics Inc. Implantable cardiac cardioverter/defibrillator with EMI suppression filter with independent ground connection
US20040046636A1 (en) * 1998-09-11 2004-03-11 Murata Manufacturing Co., Ltd. Method of producing ceramic thermistor chips
US20050195065A1 (en) * 1999-10-04 2005-09-08 Toshiya Imai Nonlinear resistor and method of manufacturing the same
US7095310B2 (en) 1999-10-04 2006-08-22 Kabushiki Kaisha Toshiba Nonlinear resistor and method of manufacturing the same
US20020133936A1 (en) * 2001-03-20 2002-09-26 Ragnar Osterlund Method of manufacturing a metal-oxide varistor with improved energy absorption capability
EP1244115A3 (en) * 2001-03-20 2004-01-02 Abb Ab Method of manufacturing a metal-oxide varistor
US6802116B2 (en) 2001-03-20 2004-10-12 Abb Ab Method of manufacturing a metal-oxide varistor with improved energy absorption capability
CN101311364B (zh) * 2008-03-10 2010-12-15 中国科学院长春光学精密机械与物理研究所 制备p型氧化锌半导体体材料的方法
US20200299109A1 (en) * 2019-03-24 2020-09-24 Nilec Solutions, Llc Apparatus, system and method for the delivery of items onto surfaces including elevated surfaces
US11945695B2 (en) * 2019-03-24 2024-04-02 Nilec Solutions, Llc Apparatus, system and method for the delivery of items onto surfaces including elevated surfaces

Also Published As

Publication number Publication date
FR2212620A1 (enrdf_load_stackoverflow) 1974-07-26
NL7317729A (enrdf_load_stackoverflow) 1974-07-02
GB1453310A (en) 1976-10-20
CA1017072A (en) 1977-09-06
NL179524C (nl) 1986-09-16
DE2365232B2 (de) 1977-12-08
IT1002565B (it) 1976-05-20
FR2212620B1 (enrdf_load_stackoverflow) 1977-09-23
DE2365232A1 (de) 1974-07-04
NL179524B (nl) 1986-04-16

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