Abstract: An apparatus is disclosed for drying materials wet with one or more solvents, particularly hygroscopic materials and materials wet with a high boiling point (low vapor pressure) solvent that are sensitive to heat. Wet material is loaded into a chamber, which is then sealed and caused to oscillate back and forth. Vacuum is enlisted to provide rapid evaporation of solvent at a lower temperature than possible at standard atmospheric pressure. The material is oscillated until a sudden decrease in the residual pressure of the chamber, which indicates completion of the drying cycle. Because vacuum is applied to an oscillating chamber, a rotary vacuum seal is not required to accomplish drying in accordance with the practice of the instant invention.

Abstract: Non-aqueous electrolytic solutions suitable for anodizing valve metal derivative anodes, methods of anodizing using non-aqueous electrolytic solutions, and capacitors prepared with non-aqueous electrolytic solutions. The non-aqueous electrolytic solution comprises glycerine and at least one soluble salt formed by the neutralization of at least one non-halogen-containing organic or inorganic acid anion with at least one alkali metal, ammonium, or protonated amine cation; wherein the acid anion is derived from an acid having a pKa lower than phosphoric acid.

Abstract: A process for edge forming a slit and cut-to-length foil having a dielectric oxide film on its face comprising forming the foil in an aqueous citrate electrolyte, preferably an aqueous ammonium citrate electrolyte, depolarizing the foil, and forming the foil in an aqueous phosphate electrolyte, preferably an ammonium dihydrogen phosphate electrolyte. Using this formation process, a foil with excellent hydration resistance and capacitance is produced.

Abstract: Aluminum surface mount capacitors containing one or more anode foil coupons are initially anodized in an aqueous phosphate solution in order to produce an anodic oxide film having extreme resistance to hydration and attack by corrosive anions for the purpose of producing surface mount capacitors at high yield and of high stability.

Abstract: A method of thermally removing binder from porous compacts pressed from metallic or ceramic materials using atmospheric pressure and binder-free compacts produced therefrom.

Abstract: Electrolytes containing water, phosphoric acid, at least one organic solvent, and at least one alkanolamine can be used for anodizing valve metals prepared from metal powder having a surface area of least 0.35 m2/g or 35,000 CV/g. The anodizing electrolytes have relatively high conductivity and are capable of being used at high anodizing currents. The anodic film produced by these electrolytes on valve metals is of substantially uniform thickness and has improved electrical parameters.

Abstract: A method of anodizing an aluminum substrate comprising heating the substrate to a first temperature of 200° C. to about 380° C.; suspending the substrate into a first electrolyte and applying a first anodizing current to the first electrolyte; rinsing the substrate; heating the substrate to a second temperature of 200° C. to about 380° C.; and suspending the substrate into a second electrolyte and applying a second anodizing current to the second electrolyte, wherein the first electrolyte and second electrolyte each comprise an aqueous solution of at least one salt of alpha-hydroxy acid.

Abstract: Aluminum surface mount capacitors containing one or more anode foil coupons are initially anodized in an aqueous phosphate solution in order to produce an anodic oxide film having extreme resistance to hydration and attack by corrosive anions for the purpose of producing surface mount capacitors at high yield and of high stability.

Abstract: A method of anodizing an aluminum substrate comprising heating the substrate to a first temperature of 200° C. to about 380° C.; suspending the substrate into a first electrolyte and applying a first anodizing current to the first electrolyte; rinsing the substrate; heating the substrate to a second temperature of 200° C. to about 380° C.; and suspending the substrate into a second electrolyte and applying a second anodizing current to the second electrolyte, wherein the first electrolyte and second electrolyte each comprise an aqueous solution of at least one salt of alpha-hydroxy acid.

Abstract: Non-aqueous electrolytic solutions suitable for anodizing valve metal derivative anodes, methods of anodizing using non-aqueous electrolytic solutions, and capacitors prepared with non-aqueous electrolytic solutions. The non-aqueous electrolytic solution comprises glycerine and at least one soluble salt formed by the neutralization of at least one non-halogen-containing organic or inorganic acid anion with at least one alkali metal, ammonium, or protonated amine cation; wherein the acid anion is derived from an acid having a pKa lower than phosphoric acid.

Abstract: A method of preparing a capacitor having at least one porous element comprising applying to the element a masking material with an ink jet printer head. Preferably the masking material is a liquid resin such as an acrylic, a polyurethane, a silicone, or a polyimide.

Abstract: Metal powders are pressed into compacts more readily through the addition of a minor percentage of dimethyl sulfone binder. Dimethyl sulfone may be dry-blended with the metal powder by mixing it in the form of a powder, or it may be wet-blended by first dissolving it in a suitable solvent, then adding it to the metal powder and evaporating the solvent. Dimethyl sulfone may be almost completely removed from compacts pressed from tantalum, etc., either by vacuum distillation or by water leaching, to leave compacts uncontaminated by the binder and suitable for further processing into capacitor anodes, etc.

Abstract: A method of anodizing valve metals with a borate polyester solution formed by the combining 2-methyl-1,3-propane diol and boric acid and heating to about 130 to about 160° C. The heating drives off water produced by esterification. A substrate is immersed in the borate polyester electrolyte solution at a temperature of about 25° C. to about 85° C. and an anodizing voltage is applied.

Abstract: A process for isolating flaw sites in the dielectric of solid electrolytic capacitor comprising immersing a conductive polymer impregnated capacitor in an electrolyte solution, and then alternately subjecting the conductive polymer impregnated capacitor to a high voltage and a low voltage; wherein the high voltage is between about 10 volts and 50 volts, and the low voltage is between about 0 volts and the voltage corresponding to 90% of the anodization voltage for pellets anodized at less than 20 volts, or the voltage at which the current drops to 50% of the peak voltage current for pellets anodized at voltages greater than or equal to 20 volts. The period of time at or above the anodization voltage is relatively short to prevent damaging the dielectric film.

Abstract: Organic acid-based binders are efficiently removed from powder metallurgy compacts, such as tantalum capacitor anode bodies, by immersion in a heated aqueous alkanolamine solution followed by rinsing in warm water. This method results in lower residual carbon and oxygen levels than are found with thermal binder removal methods.

Abstract: Metal powders are pressed into compacts more readily through the addition of a minor percentage of dimethyl sulfone binder. Dimethyl sulfone may be dry-blended with the metal powder by mixing it in the form of a powder, or it may be wet-blended by first dissolving it in a suitable solvent, then adding it to the metal powder and evaporating the solvent. Dimethyl sulfone may be almost completely removed from compacts pressed from tantalum, etc., either by vacuum distillation or by water leaching, to leave compacts uncontaminated by the binder and suitable for further processing into capacitor anodes, etc.

Abstract: A method of non-thickness-limited anodizing for valve metals and alloys which are resistant to the non-thickness-limited growth of anodic oxide, such as niobium and high niobium content alloys. Non-thickness-limited anodic oxide film growth is produced on such valve metals by employing a first glycerine-based electrolyte containing about 1 to about 3 wt % water for the initial production of anodic oxide. After the substrate is anodized using the first electrolyte, it is immersed in a second glycerine-based electrolyte having less than about 0.1 wt % water. The second electrolyte may be produced by allowing water to evaporate from the first electrolyte solution until the solution contains less than about 0.1 wt. % water.

Abstract: An electrolyte comprising water, an organic solvent selected from the group consisting of a polyethylene glycol, a polyethylene glycol monomethyl ether and mixtures thereof, and a sufficient amount of alkali metal salt of a weak organic acid, so that the electrolyte has a resistivity below about 250 ohm-cm/80° C. A method for differential anodizing porous valve metal body comprising the steps of: anodizing the bodies in a first electrolyte where the cathode surface is placed within an inch of but not in contact with the anode bodies, rinsing the bodies in deionized water, and re-anodizing the bodies in a second electrolyte, where the first electrolyte comprises water, an organic solvent selected from the group consisting of a polyethylene glycol, a polyethylene glycol monomethyl ether and mixtures thereof, and a sufficient amount of alkali metal salt of a weak organic acid so that the first electrolyte has a resistivity below about 250 ohm-cm/80° C.

Abstract: Metal powders are pressed into compacts more readily through the addition of a minor percentage of dimethyl sulfone binder. Dimethyl sulfone may be dry-blended with the metal powder by mixing it in the form of a powder, or it may be wet-blended by first dissolving it in a suitable solvent, then adding it to the metal powder and evaporating the solvent. Dimethyl sulfone may be almost completely removed from compacts pressed from tantalum, etc., either by vacuum distillation or by water leaching, to leave compacts uncontaminated by the binder and suitable for further processing into capacitor anodes, etc.

Abstract: An anodizing electrolyte containing a polyethylene glycol dimethyl ether and an electrochemical process for anodizing valve metals which permits the formulation of an anodic layer having a substantially uniform thickness and reduced flaw density.