Provided is a fine particle production apparatus and a fine particle production method capable of easily obtaining surface treated fine particles. The fine particle production apparatus produces fine particles using feedstock by means of a gas-phase process. The apparatus includes a treatment section configured to transform the feedstock into a mixture in a gas phase state by means of the gas-phase process, a feedstock supply section configured to supply the feedstock to the treatment section, a cooling section configured to cool the mixture in a gas phase state in the treatment section using a quenching gas containing an inert gas, and a supply section configured to supply a surface treating agent to fine particle bodies in a temperature region in which the surface treating agent is not denatured, the fine particle bodies being produced by cooling the mixture in the gas phase state with the quenching gas.

The present invention relates to a pigment for a black electrophoretic display having high electrical insulation and excellent dispersibility in the visible region. An objective of the present invention is to provide black titanium dioxide as a pigment for an electrophoretic display. In addition, another objective of the present invention is to provide an ink composition for an electrophoretic display comprising a black titanium dioxide pigment, and an electrophoretic display.

The present invention relates to a process for preparing oxide particles, in particular metal oxide particles, coated with silicon oxide by means of flame spray pyrolysis technology, to oxide particles, in particular metal oxide particles, coated with silicon oxide, and to a composition comprising said particles. The present invention also relates to specific oxide particles, in particular metal oxide particles, coated with silicon oxide derived from such a process, to the compositions comprising such particles and also to the uses thereof.

The present invention relates to a process for preparing oxide particles, in particular metal oxide particles, coated with silicon oxide by means of flame spray pyrolysis technology, to oxide particles, in particular metal oxide particles, coated with silicon oxide, and to a composition comprising said particles. The present invention also relates to specific oxide particles, in particular metal oxide particles, coated with silicon oxide derived from such a process, to the compositions comprising such particles and also to the uses thereof.

There has been demand for a titanium oxide organosol that has a high transparency and a high refractive index and that also exhibits an excellent viscosity stability over time. The rutile-type titanium oxide organosol according to the present invention comprises a silane coupling agent, a basic additive acting as a deflocculant, a water-insoluble solvent, and rutile-type titanium oxide particles that have been surface-treated with a hydrous oxide of at least one metal species selected from Zr, Ce, Sn, and Fe, the rutile-type titanium oxide organosol being characterized in that the Ti ratio contained in the colloidal particles in the rutile-type titanium oxide organosol is at least 60 mass% when calculated as the oxide, and the ratio of metal species at the colloidal particle surface derived from x-ray photoelectron spectroscopy is 20-50 mass%.

A coated particle having excellent thermal expansion control and electrical insulation properties includes a core of a first inorganic compound containing a metal or semimetal element P; and a shell of a second inorganic compound containing a metal or semimetal element Q. The first inorganic compound satisfies 1, and the coated particles satisfy 2 and 3. 1: |dA(T)/dT| is ≥10 ppm/°C at T1 of -200° C. to 1,200° C. A is (an a-axis lattice constant of a crystal in the first inorganic compound)/(a c-axis lattice constant of a crystal in the first inorganic compound). 2: in XPS of a surface of each of the coated particles, a ratio of a number of atoms of Q contained in the shell to a number of atoms of P contained in the core t is 45 to 300. 3: an average particle diameter of each coated particle is 0.1 to 100 .Math.m.

A powdered catalyst material on a titanium oxide basis. The powdered catalyst material includes a combined content of at least 90 wt.-% of a hydrated titanium oxide having the general formula TiO.sub.(2-x)(OH).sub.2x, with 0<x≤1, (calculated as TiO.sub.2), and a silicon dioxide and hydrated precursors of the silicon dioxide (calculated as SiO.sub.2). A weight ratio of TiO.sub.2/SiO.sub.2, determined for TiO.sub.2 and SiO.sub.2 respectively, is at least 3 and less than 30. The wt.-% is based on a total weight of the catalyst material after the catalyst material has been dried at 105° C. for at least 2 hours. The powdered catalyst material has a specific surface area of >300 m.sup.2/g and an isoelectric point of from 4.0 to 7.0.

A powdered catalyst material on a titanium oxide basis. The powdered catalyst material includes a combined content of at least 90 wt.-% of a hydrated titanium oxide having the general formula TiO.sub.(2-x)(OH).sub.2x, with 0<x≤1, (calculated as TiO.sub.2), and a silicon dioxide and hydrated precursors of the silicon dioxide (calculated as SiO.sub.2). A weight ratio of TiO.sub.2/SiO.sub.2, determined for TiO.sub.2 and SiO.sub.2 respectively, is at least 3 and less than 30. The wt.-% is based on a total weight of the catalyst material after the catalyst material has been dried at 105° C. for at least 2 hours. The powdered catalyst material has a specific surface area of >300 m.sup.2/g and an isoelectric point of from 4.0 to 7.0.

A composite cathode active material, a preparation method thereof, a cathode layer for an all-solid-state battery, and an all-solid-state battery including the cathode layer, the composite cathode active material for the all-solid-state battery including a secondary particle including a plurality of primary particles; and a buffer layer on a surface of the secondary particle, wherein the secondary particle includes a nickel lithium transition metal oxide represented by Formula 1, and the buffer layer includes a metal oxide represented by Formula 2,

Li.sub.aNi.sub.1-bM.sub.bO.sub.2  Formula 1

Li.sub.xA.sub.y-1E.sub.y2O.sub.z  Formula 2

A composite cathode active material, a preparation method thereof, a cathode layer for an all-solid-state battery, and an all-solid-state battery including the cathode layer, the composite cathode active material for the all-solid-state battery including a secondary particle including a plurality of primary particles; and a buffer layer on a surface of the secondary particle, wherein the secondary particle includes a nickel lithium transition metal oxide represented by Formula 1, and the buffer layer includes a metal oxide represented by Formula 2,

Li.sub.aNi.sub.1-bM.sub.bO.sub.2  Formula 1

Li.sub.xA.sub.y-1E.sub.y2O.sub.z  Formula 2