Abstract: An X-ray diffractometrically single-phase lithium titanium phosphate can be obtained by an industrially advantageous method. Provided is a method for producing the lithium titanium phosphate having a NASICON structure represented by the following general formula (1): Li1+xMx(Ti1?yAy)2?x(PO4)3 (1), and provided is a method comprising a first step of preparing a raw material mixed slurry (1) comprising, at least, titanium dioxide, phosphoric acid and a surfactant, a second step of heat treating the raw material mixed slurry (1) to obtain a raw material heat-treated slurry (2), a third step of mixing the raw material heat-treated slurry (2) with a lithium source to obtain a lithium-containing raw material heat-treated slurry (3), a fourth step of subjecting the lithium-containing raw material heat-treated slurry (3) to a spray drying treatment to obtain a reaction precursor containing, at least, Ti, P and Li, and a fifth step of firing the reaction precursor.

Abstract: A negative thermal expansion material made of zirconium phosphate tungstate containing an Al atom, and having a thermal expansion coefficient of ?2.0×10?6 to ?3.3×10?6/K. According to the present invention, a negative thermal expansion material made of zirconium phosphate tungstate having various thermal expansion coefficients, and an industrially advantageous manufacturing method thereof can be provided.

Abstract: There is provided a modified zirconium phosphate tungstate which effectively suppresses the elution of phosphorus ions even when it contacts with water, can develop the performance excellent as a negative thermal expansion material, and can be dispersed in a polymer compound such as a resin, and use of which enables a low-thermal expansive material containing a negative thermal expansion filler to be well produced. The surface of a zirconium phosphate tungstate particle is coated with an inorganic compound containing one or two or more elements (M) selected from Zn, Si, Al, Ba, Ca, Mg, Ti, V, Sn, Co, Fe and Zr. The BET specific surface area of the zirconium phosphate tungstate particle is preferably 0.1 m2/g to 50 m2/g.

Abstract: There is provided a modified zirconium phosphate tungstate which effectively suppresses the elution of phosphorus ions even when it contacts with water, can develop the performance excellent as a negative thermal expansion material, and can be dispersed in a polymer compound such as a resin, and use of which enables a low-thermal expansive material containing a negative thermal expansion filler to be well produced. The surface of a zirconium phosphate tungstate particle is coated with an inorganic compound containing one or two or more elements (M) selected from Zn, Si, Al, Ba, Ca, Mg, Ti, V, Sn, Co, Fe and Zr. The BET specific surface area of the zirconium phosphate tungstate particle is preferably 0.1 m2/g to 50 m2/g.

Abstract: An X-ray diffractometrically single-phase lithium titanium phosphate can be obtained by an industrially advantageous method. Provided is a method for producing the lithium titanium phosphate having a NASICON structure represented by the following general formula (1): Li1+xMx(Ti1?yAy)2?x(PO4)3 (1), and provided is a method comprising a first step of preparing a raw material mixed slurry (1) comprising, at least, titanium dioxide, phosphoric acid and a surfactant, a second step of heat treating the raw material mixed slurry (1) to obtain a raw material heat-treated slurry (2), a third step of mixing the raw material heat-treated slurry (2) with a lithium source to obtain a lithium-containing raw material heat-treated slurry (3), a fourth step of subjecting the lithium-containing raw material heat-treated slurry (3) to a spray drying treatment to obtain a reaction precursor containing, at least, Ti, P and Li, and a fifth step of firing the reaction precursor.

Abstract: A negative thermal expansion material made of zirconium phosphate tungstate containing an Al atom, and having a thermal expansion coefficient of ?2.0×10?6 to ?3.3×10?6/K. According to the present invention, a negative thermal expansion material made of zirconium phosphate tungstate having various thermal expansion coefficients, and an industrially advantageous manufacturing method thereof can be provided.

Abstract: The present application provides a negative thermal expansion material having excellent dispersibility and packing properties in a positive thermal expansion material. The negative thermal expansion material of the present invention comprises spherical zirconium tungsten phosphate having a BET specific surface area, of 2 m2/g or smaller. The degree of sphericity is preferably 0.90 or more and 1 or less. Also preferably, the negative thermal expansion material further contains at least Mg and/or V as a subcomponent element. Also preferably, the content of the subcomponent element is 0.1% by mass or more and 3% by mass or less. Also preferably, the average particle size is 1 ?m or larger and 50 ?m smaller.

Abstract: The present application provides a negative thermal expansion material having excellent dispersibility and packing properties in a positive thermal expansion material. The negative thermal expansion material of the present invention comprises spherical zirconium tungsten phosphate having a BET specific surface area of 2 m2/g or smaller. The degree of sphericity is preferably 0.90 or more and 1 or less. Also preferably, the negative thermal expansion material further contains at least Mg and/or V as a subcomponent element. Also preferably, the content of the subcomponent element is 0.1% by mass or more and 3% by mass or less. Also preferably, the average particle size is 1 ?m or larger and 50 ?m smaller.

Abstract: Provided is a method for preparing high-purity elemental phosphorus capable of simultaneously reducing both arsenic and antimony from crude white phosphorus containing a great amount of arsenic and antimony as impurities. Provided is a method for preparing high-purity elemental phosphorus, the method including bringing liquid crude white phosphorus into contact with an iodic acid-containing compound selected from iodic acid and iodates in an aqueous solvent in the presence of a chelating agent, wherein the chelating agent is selected from polyvalent carboxylic acids, polyvalent carboxylates, phosphonic acid and phosphonates.

Abstract: Provided is a method for preparing high-purity elemental phosphorus capable of simultaneously reducing both arsenic and antimony from crude white phosphorus containing a great amount of arsenic and antimony as impurities. Provided is a method for preparing high-purity elemental phosphorus, the method including bringing liquid crude white phosphorus into contact with an iodic acid-containing compound selected from iodic acid and iodates in an aqueous solvent in the presence of a chelating agent, wherein the chelating agent is selected from polyvalent carboxylic acids, polyvalent carboxylates, phosphonic acid and phosphonates.

Abstract: A high purity metaphosphate is characterized in that the concentration of each coloring metal element serving as an impurity is 5 ppm or less. The metaphosphate is an aluminum salt, a barium salt, a calcium salt, a magnesium salt, or a strontium salt. The aluminum salt is suitably produced by means of a production method comprising a first step of producing a reaction mixture containing aluminum biphosphate by reacting an aluminum compound with phosphoric acid by heating, a second step of placing the reaction mixture containing aluminum biphosphate obtained in the first step in a firing vessel on which aluminum metaphosphate powder is spread in advance and subjecting the reaction mixture to firing, and a third step of pulverizing the fired product obtained in the second step.

Abstract: An aqueous zinc nitrite solution which contains substantially no calcium (Ca) ions is provided, in which, in terms of the aqueous zinc nitrite [Zn(NO2)2] solution having an NO2 concentration of 10% by weight, the sodium (Na) ion concentration is 200 to 2000 ppm and the sulfate (SO4) ion concentration is 20 ppm or less in the solution. The aqueous zinc nitrite solution can be prepared by providing a zinc compound and an alkali nitrite as raw materials and subjecting the raw materials to electrolytic synthesis through a double decomposition reaction using an ion-exchange membrane as a diaphragm. As the aqueous zinc nitrite solution is provided, an extremely efficient metal surface treatment is made possible which has a reduced amount of sodium ions. In particular, it contains substantially no sulfate ions and no calcium ions.

Abstract: The red phosphorus base flame retardant for an epoxy resin is provided, which has red phosphorus particles coated with a thermosetting resin containing an anhydrous zinc compound. The coated red phosphorus has properties that a slurry having the coated red phosphorus dispersed in 10% by weight into water at 20° C. has an electric conductivity of 30 ?s/cm or below, the slurry having been left standing at 80° C. for 20 hours has an electric conductivity of 150 ?s/cm or below, and when 80 ml of water is added to 8 g of the coated red phosphorus and heated at 80° C. for 20 hours, a concentration of PO4 ions eluted is 10 ppm or below.

Abstract: An aqueous zinc nitrite solution which contains substantially no calcium (Ca) ions is provided, in which, in terms of the aqueous zinc nitrite [Zn(NO2)2] solution having an NO2 concentration of 10% by weight, the sodium (Na) ion concentration is 200 to 2000 ppm and the sulfate (SO4) ion concentration is 20 ppm or less in the solution. The aqueous zinc nitrite solution can be prepared by providing a zinc compound and an alkali nitrite as raw materials and subjecting the raw materials to electrolytic synthesis through a double decomposition reaction using an ion-exchange membrane as a diaphragm. As the aqueous zinc nitrite solution is provided, an extremely efficient metal surface treatment is made possible which has a reduced amount of sodium ions. In particular, it contains substantially no sulfate ions and no calcium ions.

Abstract: A red phosphorus base flame retardant for an epoxy resin, which can suppress oxo acid of phosphorus from eluting from red phosphorus and can impart remarkable flame retardancy to an epoxy resin for a semiconductor sealing material. The red phosphorus base flame retardant for an epoxy resin comprises coated red phosphorus which has the surface of red phosphorus particles coated with a thermosetting resin containing an anhydrous zinc compound or the surface of red phosphorus particles coated with an inorganic substance and further coated with a thermosetting resin containing an anhydrous zinc compound. The coated red phosphorus has properties that a slurry having the coated red phosphorus dispersed in 10% by weight into water at 20° C. has an electric conductivity of 30 &mgr;s/cm or below, the slurry having been left standing at 80° C. for 20 hours has an electric conductivity of 150 &mgr;s/cm or below, and when 80 ml of water is added to 8 g of the coated red phosphorus and heated at 80 ° C.

Abstract: An aqueous zinc nitrite solution contains as impurities 10 ppm or less of sodium (Na) and 100 ppm or less of sulfate ions (SO4) when the aqueous solution has a concentration of zinc nitrite [Zn(NO2)2] of 10% by weight in terms of NO2. Also, disclosed is a method for preparing an aqueous zinc nitrite solution, including a first step of reacting zinc sulfate with calcium nitrite to form an aqueous zinc nitrite solution and a second step of purifying the aqueous zinc nitrite solution.

Abstract: The present invention is to provide a metal surface-treating method which is capable of forming a zinc phosphate coat suitable for the cationic electrodeposition coating of a metallic shaped product, particularly a metallic shaped product having both an iron type metallic surface and a zinc type metallic surface and is suited to a closed system.

Abstract: This invention provides a metal surface-treating method which comprises a chemical conversion step of dipping a substrate in an acidic aqueous zinc phosphate solution, and using an aqueous zinc nitrite solution as an accelerator, said aqueous zinc nitrite solution being substantially free of calcium ion and containing 0 to 6500 ppm of sodium ion and 0 to 20 ppm of sulfate ion in case of assuming the concentration of zinc nitrite [Zn(NO2)2] therein to be 10 weight % as NO2.

Abstract: This invention provides a metal surface-treating method

Abstract: An aqueous zinc nitrite solution contains as impurities 10 ppm or less of sodium (Na) and 100 ppm or less of sulfate ions (SO4) when the aqueous solution has a concentration of zinc nitrite [Zn(NO2)2] of 10% by weight in terms of NO2. Also, disclosed is a method for preparing an aqueous zinc nitrite solution, including a first step of reacting zinc sulfate with calcium nitrite to form an aqueous zinc nitrite solution and a second step of purifying the aqueous zinc nitrite solution.