Ube Material Industries, Ltd.

Taiyo Nippon Sanso Corporation

Fumio Okada

Takeshi Himoto

Takashi Watanabe

Masayuki Fujimoto

Takayuki Watanabe

Yoshio Ishihara

Takashi Kishimoto

Kouichi Fukuda

Katsumasa Suzuki

Shinichi Yamamoto

Rika Nogita

Yojiro Ichimura

Kaoru Sakoda

Osamu Misumi

Acicular strontium carbonate particles are manufactured by introducing gaseous carbon dioxide into an aqueous solution or suspension of strontium hydroxide having a concentration of 1 to 20 wt. %, at a flow rate of 0.5 to 200 mL/min., relative to one gram of the strontium hydroxide, while stirring the solution or suspension in the presence of a dicarboxylic acid, in which the dicarboxylic acid comprises a divalent linear hydrocarbon group having one to four carbon atoms and carboxyl group bonded to each terminals, with the proviso that the linear hydrocarbon group may be substituted with one or more Calkyl groups, and thus carbonating the strontium hydroxide.

Process for manufacturing needle-shaped strontium carbonate particles

Dispersibility of an alkaline earth metal carbonate micropowder in a polymer resin or in an organic solvent is improved by treating the surface of the alkaline earth metal micropowder with a surfactant having hydrophilic groups and hydrophobic groups and groups that form anions in water.

Alkaline earth metal carbonate micropowder

An acicular strontium carbonate fine powder having a mean length of 150 nm or less and a mean aspect ratio of 1.5 or more and containing acicular strontium carbonate particles having a length of 200 nm or more in an amount of 5% or less in terms of number of acicular particles is improved in its dispersibility in hydrophobic organic solvent by treating the acicular strontium carbonate fine powder with a combination of polycarboxylic acid having a side chain of a polyoxyalkylene group or its anhydride and amine having a polyoxyalkylene group and a hydrocarbyl group.

Acicular strontium carbonate fine powder treated with a combination of compounds containing a polyoxyalkylene group

A fine strontium carbonate powder having a BET specific surface area of 20 to 150 m/g, which comprises spherical particles having a mean aspect ratio of 2.0 or less shows high dispersibility in liquid media and is of value for producing dielectric ceramic materials such as strontium titanate.

Strontium carbonate micropowder and process for production

A fine powder of an alkaline earth metal carbonate selected from the group consisting of barium carbonate, strontium carbonate and calcium carbonate, in which a primary particle of the powder has a mean diameter of 30 to 90 nm, in which the mean diameter is measured on a circle obtained from a projected area of the primary particle, and in which an accumulated volume of micropores having a pore size in the range of 10 to 20 nm is not less than 5&#xd7;10cm/g can be easily dispersed in an aqueous medium in the form of essentially primary particles by an industrially employable dispersing method.

Highly dispersible fine powder of alkaline earth metal carbonate

A granular material having a high strength and a large BET specific surface area composed of porous particles comprising calcium oxide and calcium hydroxide wherein the calcium oxide is contained in an amount of 30 to 80 weight % based on a total amount of the calcium oxide and calcium hydroxide and the porous particles have a BET specific surface area of 40 m/g or more, or composed of porous particles comprising calcium oxide, magnesium oxide, calcium hydroxide, and magnesium hydroxide wherein a ratio of an amount of magnesium to a total of an amount of calcium and an amount of magnesium is in the range of 0.05 to 0.80, a total hydroxide content in the whole particles is in the range of 1 to 20 weight % and the porous particles have a BET specific surface area of 50 m/g or more.

Growing community of inventors

Ube, Japan

Fumio Okada