Showa Denko K.k.

Showa Denko Kabushiki Kaisha

Kouichi Wada

Kazumi Naito

Kazuhiro Omori

Toshiya Kawasaki

Nobuaki Ishii

Michihiro Takama

Yasuo Tsumita

Junko Futami

Ichiro Fujita

The present invention is intended to provide a process capable of efficiently producing highly purified succinic acid from an alkali metal succinate by a simple separation and purification process. The process for producing succinic acid in the present invention comprises (1) the step to add sulfuric acid into a solution containing an alkali metal succinate, (2) the step to precipitate and remove the crystal of an alkali metal sulfate from said solution, and (3) the step to precipitate and recover the crystal of succinic acid. The removal of the crystal of an alkali metal sulfate in the step (2) is performed by a solid-liquid separation in a state that the crystal of alkali metal sulfate is precipitated by concentrating and heating the solution that is obtained by adding sulfuric acid in the step (1) and succinic acid is dissolved in the solution.

Process for producing succinic acid

(1) A niobium monoxide powder for a capacitor represented by formula: NbO(x=0.8 to 1.2) and optionally containing other elements in an amount of 50 to 200,000 ppm, having a tapping density of 0.5 to 2.5 g/ml, an average particle size of 10 to 1000 &#x3bc;m, angle of repose from 10&#xb0; to 60&#xb0;, the BET specific surface area from 0.5 to 40 m/g and a plurality of pore diameter peak tops in the pore distribution, and a producing method thereof; (2) a niobium monoxide sintered body, which is obtained by sintering the above niobium monoxide powder and, having a plurality of pore diameter peak tops in a range of 0.01 &#x3bc;m to 500 &#x3bc;m, preferably, the peak tops of two peaks among the plurality of pore diameter peak tops having a highest relative intensity are present in the range of 0.2 to 0.7 &#x3bc;m and in the range of 0.7 to 3 &#x3bc;m, respectively, and a producing method thereof; (3) a capacitor using the above sintered body and a producing method thereof; and (4) an electronic circuit and electronic device using the above capacitor.

Niobium monoxide powder, niobium monoxide sintered body and capacitor using the sintered body

(1) A niobium powder for a capacitor having a tapping density of 0.5 to 2.5 g/ml, an average particle size of 10 to 1000 &#x3bc;m, angle of repose from 10&#xb0; to 60&#xb0;, the BET specific surface area from 0.5 to 40 m/g and a plurality of pore diameter peak tops in the pore distribution, and a producing method thereof; (2) a niobium sintered body, which is obtained by sintering the above niobium powder and, having a plurality of pore diameter peak tops in a range of 0.01 &#x3bc;m to 500 &#x3bc;m, preferably, the peak tops of two peaks among the plurality of pore diameter peak tops having a highest relative intensity are present in the range of 0.2 to 0.7 &#x3bc;m and in the range of 0.7 to 3 &#x3bc;m, respectively, and a producing method thereof; (3) a capacitor using the above sintered body and a producing method thereof; and (4) an electronic circuit and electronic device using the above capacitor.

Niobium powder, niobium sintered body and capacitor using the sintered body

Provided are a silica-coated mixed crystal oxide particle which has high dispersibility, excellent visible light transparency and superior ultraviolet-shielding capability and which is sufficiently reduced in the photocatalytic activity; an economical production process thereof; and an ultraviolet-shielding cosmetic material containing the silica-coated mixed crystal oxide particle, which is particularly excellent in the visible light transparency. The surface of a mixed crystal oxide particle having a BET specific surface area of 10 to 200 m/g and containing primary particles in a mixed crystal is covered with a dense and thin film silica.

Silica-coated mixed crystal oxide particle, production process thereof and cosmetic material using the same

A niobium hydride or niobium hydride alloy is ground at a temperature of &#x2212;200 to 30&#xb0; C. in the presence of a dispersion medium to obtain a niobium powder for capacitors, having a low oxygen content, the niobium powder for capacitors is granulated to obtain a niobium granulated product for capacitors, having an average particle size of 10 to 500 &#x3bc;m, the niobium powder or granulated powder for capacitors is sintered to obtain a sintered body, and a capacitor is fabricated by forming a dielectric material on the surface of the sintered body and providing another part electrode on the dielectric material, whereby a capacitor having good LC characteristics and less dispersed in the LC characteristics is obtained.

Production process for niobium powder

To provide a cosmetic composition having excellent ultraviolet protection against both UVB and UVA, causing neither unpleasant whitening to the applied skin nor skin irritation, and ensuring good feeling on use and high safety and high stability without causing decomposition of the ingredients blended in the cosmetic material, such as organic ultraviolet absorber. A cosmetic composition obtained by using fine particulate titanium oxide and fine particulate zinc oxide each surface-treated with silica, alumina or alumina/silica and having a primary particle size of 0.01 to 0.2 &#x3bc;m in combination and blending titanium oxide and zinc oxide at a mass ratio of 1:4 to 2:3, wherein SPF is maintained as compared with the case where the mass ratio of titanium oxide to zinc oxide is 1:0, and when applied to a thickness of 10 &#x3bc;m, the whiteness W value measured using the CIE color specification system is 20 or less.

Cosmetic composition

A niobium powder for a capacitor having a tapping density of 0.5 to 2.5 g/ml, and average particle size of 10 to 1000 &#x3bc;mum, angle of repose form 10&#xb0; to 60&#xb0;, the BET specific surface area from 0.5 to 40 m/g and a plurity of pore diameter peak tops in the pore distribution, and a producing method therof; (2) a niobium sintered body, which is obtained by sintering the above niobium powder and, having a plurality of pore diameter peak tops in a range of 0.01 &#x3bc;mum to 500 &#x3bc;mum, preferably, the peak tops of two peaks among the plurality of pore diameter peak tops having a highest relative intensity are present in the range of 0.2 to 0.7 &#x3bc;mum and in the range of 0.7 to 3 &#x3bc;mum, respectively, and a producing method thereof; (3) a capacitor using the above sintered body and a producing method thereof, and (4) an electronic circuit and electronic device using the above capacitor.

A niobium hydride or niobium hydride alloy is ground at a temperature of &minus;200 to 30&deg; C. in the presence of a dispersion medium to obtain a niobium powder for capacitors, having a low oxygen content, the niobium powder for capacitors is granulated to obtain a niobium granulated product for capacitors, having an average particle size of 10 to 500 &mgr;m, the niobium powder or granulated powder for capacitors is sintered to obtain a sintered body, and a capacitor is fabricated by forming a dielectric material on the surface of the sintered body and providing another part electrode on the dielectric material, whereby a capacitor having good LC characteristics and less dispersed in the LC characteristics is obtained.

A cosmetic composition comprising titanium oxide coated with one or both of silica and alumina or zinc oxide coated with one or both of silica and alumina, and a thickening polymer having a carboxyl group in the side chain, preferably a carboxyvinyl polymer, wherein when 10% by mass of silica- and/or alumina-coated titanium oxide or silica- and/or alumina-coated zinc oxide is dispersed in an aqueous solution containing 0.133% by mass of a carboxyvinyl polymer, the viscosity after the passing of 100 hours is 50% or more of the initial viscosity. A cosmetic composition comprising titanium oxide coated with one or both silica and alumina or zinc oxide coated with one or both of silica and alumina, and a thickening polymer having a carboxyl group in the side chain of the invention, can maintain emulsion stability by thickening of polymer for a long period of time and can be widely and suitably used for ultraviolet shielding cosmetic materials or the like having preparation form stability.

Growing community of inventors

Kanagawa, Japan

Kouichi Wada