Method of producing manganese oxide solid electrolyte capacitor

Claim 1

A method of producing a solid electrolyte capacitor having a layer of manganese dioxide as the electrolyte, the method comprising the steps of: a. preparing a substrate by forming a dielectric oxide coating on a surface of a valve metal member; b. immersing said substrate in an aqueous solution consisting of water and manganese nitrate; c. heating the wet substrate to cause pyrolytic decomposition of manganese nitrate to manganese dioxide; d. immersing said substrate subsequently to said step (c) in an aqueous solution consisting of water and manganese nitrate; and e. heating the wet substrate subsequently to said step (d) to cause pyrolytic decomposition of manganese nitrite to manganese dioxide, one of said steps (c) and (e) being carried out in a furnace of a hot air circulation type by flowing a heated air around said substrate, the other being carried out in a heating chamber of a radiant furnace, said chamber being semi-closed and in communication with the atmosphere exclusively through at least one vent formed in the wall of said chamber, heat for said pyrolytic decomposition in said radiant furnace being transferred from the wall of said chamber dominantly by radiation, said at least one vent having a predetermined area such that said pyrolytic decomposition proceeds under a positive pressure of a small magnitude due to a relatively prolonged retention of gaseous decomposition products in said chamber.

Claim 2

A method of producing a solid electrolyte capacitor having a layer of manganese dioxide as the electrolyte, the method comprising the steps of: a. preparing a substrate by forming a dielectric oxide coating on a surface of a valve metal member; b. immersing said substrate in an aqueous solution consisting of water and manganese nitrate; c. heating the wet substrate to cause pyrolytic decomposition of manganese nitrate to manganese dioxide; d. immersing said substrate subsequently to said step (c) in an aqueous solution consisting of water and manganese nitrate; and e. heating the wet substrate subsequently to said step (d) to cause pyrolytic decomposition of manganese nitrite to manganese dioxide, one of said steps (c) and (e) being carried out in a furnace of a hot air circulation type by flowing a heated air around said substrate, the other being carried out in a heating chamber of a radiant furnace, said chamber being semi-closed and in communication with the atmosphere exclusively through at least one vent formed in the wall of said chamber, heat for said pyrolytic decomposition in said radiant furnace being transferred from the wall of said chamber dominantly by radiation, said at least one vent having a predetermined area such that said pyrolytic decomposition proceeds under a positive pressure of a small magnitude due to a relatively prolonged retention of gaseous decomposition products in said chamber.

Claim 10

A method of producing a solid electrolyte capacitor having a layer of manganese dioxide as the electrolyte, the method comprising the steps of: a. preparing a substrate by forming a dielectric oxide coating on a surface of a valve metal member; b. immersing said substrate in an aqueous solution of manganese nitrite; c. heating the wet substrate to cause pyrolytic decompositon of manganese nitrite to manganese dioxide in a furnace of a hot air circulation type by flowing heated air around the substrate; d. immersing said substrate and in aqueous solution consisting of water and manganese nitrite; and e. heating the wet substrate subsequently to said step (d) to cause pyrolytic decomposition of manganese nitrate to manganese dioxide in a heating chamber of a radiant furnace, said chamber being semi-closed and in communication with the atmosphere exclusively through at least one vent formed in the wall of said chamber, heat for said pyrolytic decomposition in said radiant furnace being transferred from the wall of said chamber dominantly by radiaton, said at least one vent having a predetermined area such that said pyrolytic decomposition proceeds under a positive pressure of a small magnitude due to a relatively prolonged retention of gaseous decomposition products in said chamber, a first combination of said steps (b) and (c) being carried out at least once in advance of a second combination of said steps (d) and (e), and said second combination being carried out at least once after said first combination is carried out entirely.

Claim 11

A method of producing a solid electrolyte capacitor having a layer of manganese dioxide as the electrolyte, the method comprising the steps of: a. preparing a substrate by forming a dielectric oxide coating on a surface of a valve metal member; b. immersing said substrate in an aqueous solution of manganese nitrite; c. heating the wet substrate to cause pyrolytic decompositon of manganese nitrite to manganese dioxide in a furnace of a hot air circulation type by flowing heated air around the substrate; d. immersing said substrate and in aqueous solution consisting of water and manganese nitrite; and e. heating the wet substrate subsequently to said step (d) to cause pyrolytic decomposition of manganese nitrate to manganese dioxide in a heating chamber of a radiant furnace, said chamber being semi-closed and in communication with the atmosphere exclusively through at least one vent formed in the wall of said chamber, heat for said pyrolytic decomposition in said radiant furnace being transferred from the wall of said chamber dominantly by radiaton, said at least one vent having a predetermined area such that said pyrolytic decomposition proceeds under a positive pressure of a small magnitude due to a relatively prolonged retention of gaseous decomposition products in said chamber, a first combination of said steps (b) and (c) being carried out at least once in advance of a second combination of said steps (d) and (e), and said second combination being carried out at least once after said first combination is carried out entirely.