A capacitor that includes: a base material having: a substrate; a first conductive portion on at least one main surface of the substrate; and an insulating-resin layer on a surface of the first conductive portion; a plurality of fibrous conductive cores, a first end portion of each of the plurality of the fibrous conductive cores being in contact with the first conductive portion through the insulating-resin layer; a dielectric layer covering a portion of the plurality of the fibrous conductive cores exposed from the base material; a conductive polymer layer covering the dielectric layer such that gaps are provided in spaces between the plurality of the fibrous conductive cores; and a second conductive portion in contact with the conductive polymer layer at a second end portion of the plurality of the fibrous conductive cores.

A separator for aluminum electrolytic capacitors, the separator being formed of natural cellulose fibers and beaten regenerated cellulose fibers, and having excellent tear strength, short-circuit resistance and impedance characteristics. The separator for aluminum electrolytic capacitors is interposed between a positive electrode and a negative electrode of an aluminum electrolytic capacitor, and is formed of from 50% by mass to 90% by mass of natural cellulose fibers and from 50% by mass to 10% by mass of beaten regenerated cellulose fibers. The separator for aluminum electrolytic capacitors is configured to have a specific tear strength of from 20 to 100 mN.Math.m.sup.2/g and a short-circuit rate of 10% or less during application of 500 V in separator dielectric breakdown testing.

A separator for aluminum electrolytic capacitors, the separator being formed of natural cellulose fibers and beaten regenerated cellulose fibers, and having excellent tear strength, short-circuit resistance and impedance characteristics. The separator for aluminum electrolytic capacitors is interposed between a positive electrode and a negative electrode of an aluminum electrolytic capacitor, and is formed of from 50% by mass to 90% by mass of natural cellulose fibers and from 50% by mass to 10% by mass of beaten regenerated cellulose fibers. The separator for aluminum electrolytic capacitors is configured to have a specific tear strength of from 20 to 100 mN.Math.m.sup.2/g and a short-circuit rate of 10% or less during application of 500 V in separator dielectric breakdown testing.

Many electronic devices may employ electrolytic polymer capacitors in their power supplies for noise filtering, decoupling/bypassing, frequency conversion and DC-DC and AC-DC conversion. However, some polymer capacitors exhibit an anomalous charging current phenomenon, which may prevent proper charging and cause failure in power circuits of the electronic devices. Disclosed herein are polymer capacitors that have a wide band gap material layer between an insulator/dielectric and a polymer cathode, a charge depletion region in the insulator/dielectric, or both, that may mitigate the anomalous charging current.

A capacitor that comprises a capacitor element is provided. The capacitor element comprises a deoxidized and sintered anode body that is formed from a powder having a specific charge of about 35,000 μF*V/g or more. Further, a dielectric overlies the anode body and a solid electrolyte overlies the dielectric. The capacitor also exhibits a normalized aged leakage current of about 0.1% or less.

A capacitor that comprises a capacitor element is provided. The capacitor element comprises a deoxidized and sintered anode body that is formed from a powder having a specific charge of about 35,000 μF*V/g or more. Further, a dielectric overlies the anode body and a solid electrolyte overlies the dielectric. The capacitor also exhibits a normalized aged leakage current of about 0.1% or less.

In production of an electrode for an aluminum electrolytic capacitor, a hydrated film is formed onto an aluminum electrode including a porous layer by immersing the aluminum electrode into a first hydration treatment liquid having a temperature of 80° C. or more in a first hydration treatment step (ST1) and thereafter the aluminum electrode is heated in an atmosphere having a temperature of 150° C. or more and 350° C. or less in a dehydration step (ST2). Subsequently, a hydrated film is formed onto the aluminum electrode by immersing the aluminum electrode into a second hydration treatment liquid having a temperature of 80° C. or more in a second hydration treatment step (ST3) and thereafter chemical formation of the aluminum electrode is performed at 400 V or more and further 600 V or more in a chemical formation step.

In production of an electrode for an aluminum electrolytic capacitor, a hydrated film is formed onto an aluminum electrode including a porous layer by immersing the aluminum electrode into a first hydration treatment liquid having a temperature of 80° C. or more in a first hydration treatment step (ST1) and thereafter the aluminum electrode is heated in an atmosphere having a temperature of 150° C. or more and 350° C. or less in a dehydration step (ST2). Subsequently, a hydrated film is formed onto the aluminum electrode by immersing the aluminum electrode into a second hydration treatment liquid having a temperature of 80° C. or more in a second hydration treatment step (ST3) and thereafter chemical formation of the aluminum electrode is performed at 400 V or more and further 600 V or more in a chemical formation step.

A capacitor including a conductive porous base material having a plurality of pores, a dielectric layer on the conductive porous base material, an upper electrode on the dielectric layer, and an insulating material that extends into the plurality of pores.

A capacitor including a conductive porous base material having a plurality of pores, a dielectric layer on the conductive porous base material, an upper electrode on the dielectric layer, and an insulating material that extends into the plurality of pores.