Abstract: A method for producing agglomerated tantalum particles, comprising: a step for grinding secondary tantalum particles, which are obtained by reducing a tantalum salt, and adding water thereto to give a water-containing mass; a step for drying said water-containing mass to give a dry mass; a step for sieving said dry mass to give spherical particles; and a step for heating said spherical particles. A mixed tantalum powder comprising a mixture of agglomerated tantalum particles (X) with agglomerated tantalum particles (Y), wherein said agglomerated tantalum particles (X) show a cumulative percentage of particles with particle size of 3 ?m or less of 5 mass % or less after 25 W ultrasonic radiation for 10 min, while said agglomerated tantalum particles (Y) show a cumulative percentage of particles with particle size of 3 ?m or less of 10 mass % or more after 25 W ultrasonic radiation for 10 min.

Abstract: A method for producing agglomerated tantalum particles, comprising: a step for grinding secondary tantalum particles, which are obtained by reducing a tantalum salt, and adding water thereto to give a water-containing mass; a step for drying said water-containing mass to give a dry mass; a step for sieving said dry mass to give spherical particles; and a step for heating said spherical particles. A mixed tantalum powder comprising a mixture of agglomerated tantalum particles (X) with agglomerated tantalum particles (Y), wherein said agglomerated tantalum particles (X) show a cumulative percentage of particles with particle size of 3 ?m or less of 5 mass % or less after 25 W ultrasonic radiation for 10 min, while said agglomerated tantalum particles (Y) show a cumulative percentage of particles with particle size of 3 ?m or less of 10 mass % or more after 25 W ultrasonic radiation for 10 min.

Abstract: A method for producing agglomerated tantalum particles, comprising: a step for grinding secondary tantalum particles, which are obtained by reducing a tantalum salt, and adding water thereto to give a water-containing mass; a step for drying said water-containing mass to give a dry mass; a step for sieving said dry mass to give spherical particles; and a step for heating said spherical particles. A mixed tantalum powder comprising a mixture of agglomerated tantalum particles (X) with agglomerated tantalum particles (Y), wherein said agglomerated tantalum particles (X) show a cumulative percentage of particles with particle size of 3 ?m or less of 5 mass % or less after 25 W ultrasonic radiation for 10 min, while said agglomerated tantalum particles (Y) show a cumulative percentage of particles with particle size of 3 ?m or less of 10 mass % or more after 25 W ultrasonic radiation for 10 min.

Abstract: Methods to at least partially reduce a niobium oxide are described wherein the process includes mixing the niobium oxide and niobium powder to form a powder mixture that is then heat treated to form heat treated particles which then undergo reacting in an atmosphere which permits the transfer of oxygen atoms from the niobium oxide to the niobium powder, and at a temperature and for a time sufficient to form an oxygen reduced niobium oxide. Oxygen reduced niobium oxides having high porosity are also described as well as capacitors containing anodes made from the oxygen reduced niobium oxides.

Abstract: A method for producing agglomerated tantalum particles, comprising: a step for grinding secondary tantalum particles, which are obtained by reducing a tantalum salt, and adding water thereto to give a water-containing mass; a step for drying said water-containing mass to give a dry mass; a step for sieving said dry mass to give spherical particles; and a step for heating said spherical particles. A mixed tantalum powder comprising a mixture of agglomerated tantalum particles (X) with agglomerated tantalum particles (Y), wherein said agglomerated tantalum particles (X) show a cumulative percentage of particles with particle size of 3 ?m or less of 5 mass % or less after 25 W ultrasonic radiation for 10 min, while said agglomerated tantalum particles (Y) show a cumulative percentage of particles with particle size of 3 ?m or less of 10 mass % or more after 25 W ultrasonic radiation for 10 min.

Abstract: Methods to at least partially reduce a niobium oxide are described wherein the process includes mixing the niobium oxide and niobium powder to form a powder mixture that is then heat treated to form heat treated particles which then undergo reacting in an atmosphere which permits the transfer of oxygen atoms from the niobium oxide to the niobium powder, and at a temperature and for a time sufficient to form an oxygen reduced niobium oxide. Oxygen reduced niobium oxides having high porosity are also described as well as capacitors containing anodes made from the oxygen reduced niobium oxides.

Abstract: Nb1-xTaxO powder wherein x is 0.1 to 0.5 is described. Further, this powder, as well as niobium suboxide powders, can be doped with at least one dopant oxide. Pressed bodies of the powder, sintered bodies, capacitor anodes, and capacitors are also described.

Abstract: Nb1-xTaxO powder wherein x is 0.1 to 0.5 is described. Further, this powder, as well as niobium suboxide powders, can be doped with at least one dopant oxide. Pressed bodies of the powder, sintered bodies, capacitor anodes, and capacitors are also described.

Abstract: A method to passivate a metal or metal oxide or metal suboxide powder, especially a valve metal powder such as tantalum or niobium and the passivated powders formed therefrom are described. The method includes passivating a starting powder with a gas having at least 25 wt. % oxygen present. Passivation is preferably achieved without performing any evacuation steps. Capacitors made from the passivated powders are also described.

Abstract: Valve metal suboxides having a primary suboxide phase and optionally a secondary suboxide phase, a valve metal phase, and/or at least one tertiary suboxide phase can be present in varying amounts. Also disclosed is anodes and capacitors containing the valve metal suboxides of the present invention. Also, a method to prepare a valve metal suboxide is further described which includes granulating one or more of the starting materials individually or together and/or granulating the final product.

Abstract: Methods to at least partially reduce a niobium oxide are described wherein the process includes mixing the niobium oxide and niobium powder to form a powder mixture that is then heat treated to form heat treated particles which then undergo reacting in an atmosphere which permits the transfer of oxygen atoms from the niobium oxide to the niobium powder, and at a temperature and for a time sufficient to form an oxygen reduced niobium oxide. Oxygen reduced niobium oxides having high porosity are also described as well as capacitors containing anodes made from the oxygen reduced niobium oxides.

Abstract: Methods to at least partially reduce a niobium oxide are described wherein the process includes mixing the niobium oxide and niobium powder to form a powder mixture that is then heat treated to form heat treated particles which then undergo reacting in an atmosphere which permits the transfer of oxygen atoms from the niobium oxide to the niobium powder, and at a temperature and for a time sufficient to form an oxygen reduced niobium oxide. Oxygen reduced niobium oxides having high porosity are also described as well as capacitors containing anodes made from the oxygen reduced niobium oxides.

Abstract: Nb1-xTaxO powder wherein x is 0.1 to 0.5 is described. Further, this powder, as well as niobium suboxide powders, can be doped with at least one dopant oxide. Pressed bodies of the powder, sintered bodies, capacitor anodes, and capacitors are also described.

Abstract: A method to passivate a metal or metal oxide or metal suboxide powder, especially a valve metal powder such as tantalum or niobium and the passivated powders formed therefrom are described. The method includes passivating a starting powder with a gas having at least 25 wt. % oxygen present. Passivation is preferably achieved without performing any evacuation steps. Capacitors made from the passivated powders are also described.

Abstract: Methods to at least partially reduce a niobium oxide are described wherein the process includes mixing the niobium oxide and niobium powder to form a powder mixture that is then heat treated to form heat treated particles which then undergo reacting in an atmosphere which permits the transfer of oxygen atoms from the niobium oxide to the niobium powder, and at a temperature and for a time sufficient to form an oxygen reduced niobium oxide. Oxygen reduced niobium oxides having high porosity are also described as well as capacitors containing anodes made from the oxygen reduced niobium oxides.

Abstract: Valve metal suboxides having a primary suboxide phase and optionally a secondary suboxide phase, a valve metal phase, and/or at least one tertiary suboxide phase can be present in varying amounts. Also disclosed is anodes and capacitors containing the valve metal suboxides of the present invention. Also, a method to prepare a valve metal suboxide is further described which includes granulating one or more of the starting materials individually or together and/or granulating the final product.

Abstract: The present invention is directed to a silicate-based sintering aid and a method for producing the sintering aid. The sintering aid, or frit, may be added to dielectric compositions, including barium titanate-based compositions, to lower the sintering temperature. The sintering aid may be a single or multi-component silicate produced via a precipitation reaction by mixing solutions including silicon species and alkaline earth metal species. The sintering aid can be produced as nanometer-sized particles, or as coatings on the surfaces of pre-formed dielectric particles. Dielectric compositions that include the sintering aid may be used to form dielectric layers in MLCCs and, in particular, ultra-thin dielectric layers.

Abstract: Barium titanate-based compositions having a high tetragonality and methods of forming the same are provided, as well as devices formed from the compositions. The barium titanate-based compositions advantageously have a high tetragonality and small particle sizes. For example, in some embodiments, the barium titanate-based compositions have a tetragonality of greater than about 2.0 and an average particle size of less than about 0.3 micron. Some methods involve achieving high tetragonality by limiting the concentration of certain metals (other than barium or titanium) in the compositions and/or heat treating the compositions at relatively high temperatures. In some methods, the A/B ratio of the composition may be adjusted prior to heat treatment to ensure that a small particle size is maintained during heat treatment.

Abstract: The invention provides a method for producing barium titanate-based particulate compositions. The method includes a heat treatment step, separate from a sintering step, that involves treating a barium titanate-based particulate composition at a temperature between about 700° C. and about 1150° C. to increase average particle size. The increased average particle size can improve the electrical properties (i.e., dielectric constant and dissipation factor) of the heat-treated composition as compared to the composition prior to heat treating. The heat-treated composition may be further processed, for example, by producing a dispersion which may be cast and sintered to form a dielectric layer in electronic components including MLCCs.

Abstract: The invention provides dielectric (e.g., barium titanate-based) particles having passivated surfaces. The surfaces may be passivated, for example, using methods that limit the dissolution of divalent metals (e.g., barium) from the particle surfaces in subsequent processing steps. In some methods, the surfaces are passivated by washing the particles to form a divalent metal-depleted surface region. In other methods, the particles may be coated with a divalent metal insoluble compound or a divalent metal free compound. Advantageously, the surface passivated particles may be uniformly dispersed to form dispersions that are stable for long periods of time and may be further processed to form articles having particles uniformly dispersed therein. The particles are particularly suitable in the formation of polymer/dielectric composites that may be used in embedded capacitor applications.