AC Etching of aluminum capacitor foil
AssigneeSprague Electric Company
InventorMulk R. Arora
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Abstract
Aluminum capacitor foil is etched using AC current and an etchant bath comprising 0.8 to 1.5 M hydrochloric acid, 0.4 to 0.5 M aluminum chloride, 0.04 to 0.3 M nitric acid, and 0.05 to 0.2 M tartaric acid. The frequency of the alternating current is 12 to 20 Hz, and the bath temperature is 30.degree. to 40.degree. C.
Claims4
A process for the etching of aluminum capacitor foil comprising passing the foil through an electrolytic bath under the influence of alternating current, said bath consisting essentially of 0.8 to 1.5 moles/liter of hydrochloric acid, 0.4 to 0.5 moles/liter aluminum chloride, 0.04 to 0.3 moles/liter of nitric acid, and 0.05 to 0.2 moles/liter of tartaric acid, said alternating current having a frequency of 12 to 20 Hz, at a temperature of about 30.degree. to 40.degree. C. rendering said foil more amenable to subsequent processing.
Dependencies are inferred from the claim text.