The invention relates to a method for preparing synthetic mineral particles with formula (Al.sub.yM.sub.1-y).sub.2(Si.sub.xGe.sub.1-x).sub.2O.sub.5(OH).sub.4, wherein M designates at least one trivalent metal selected from the group made up of gallium and the rare earths, which comprises the following steps: preparing a gel which is a precursor of said synthetic mineral particles by a co-precipitation reaction of at least one salt of metal selected among aluminium and M with at least one silicon source selected from the group made up of potassium metasilicate, sodium metasilicate, potassium metagermanate and sodium metagermanate, the molar ratio of (Al.sub.yM.sub.1-y) to (Si.sub.xGe.sub.1-x) during the preparation of said precursor gel being equal to 1, at least one base being added during said co-precipitation reaction; and performing a solvothermal treatment of said precursor gel at a temperature of 250° C. to 600° C.

The invention relates to a method for preparing synthetic mineral particles with formula (Al.sub.yM.sub.1-y).sub.2(Si.sub.xGe.sub.1-x).sub.2O.sub.5(OH).sub.4, wherein M designates at least one trivalent metal selected from the group made up of gallium and the rare earths, which comprises the following steps: preparing a gel which is a precursor of said synthetic mineral particles by a co-precipitation reaction of at least one salt of metal selected among aluminium and M with at least one silicon source selected from the group made up of potassium metasilicate, sodium metasilicate, potassium metagermanate and sodium metagermanate, the molar ratio of (Al.sub.yM.sub.1-y) to (Si.sub.xGe.sub.1-x) during the preparation of said precursor gel being equal to 1, at least one base being added during said co-precipitation reaction; and performing a solvothermal treatment of said precursor gel at a temperature of 250° C. to 600° C.

The present invention concerns a process for the preparation of flocculated filler particles, wherein at least two aqueous suspensions of at least one filler material and at least one flocculating additive are combined.

A catalyst-free synthesis method for the formation of a metalorganic compound comprising a desired (first) metal may include, for example, selecting another (second) metal and an organic solvent, with the second metal being selected to (i) be more reactive with respect to the organic solvent than the first metal and (ii) form, upon exposure of the second metal to the organic solvent, a reaction by-product that is more soluble in the organic solvent than the metalorganic compound. An alloy comprising the first metal and the second metal may be first produced (e.g., formed or otherwise obtained) and then treated with the organic solvent in a liquid phase or a vapor phase to form a mixture comprising (i) the reaction by-product comprising the second metal and (ii) the metalorganic compound comprising the first metal. The metalorganic compound may then be separated from the mixture in the form of a solid.

An inorganic porous substrate having a silyl group represented by (i) and (ii) and having characteristics (iii) to (v), an inorganic porous support derived from the inorganic porous substrate, and a nucleic acid production method using the inorganic porous support: (i) a silyl group (A): a silyl group represented by the formula (i-1); (ii) a silyl group (B): at least one silyl group selected from the group consisting of silyl groups represented by (ii-1), (ii-2), and (ii-3); (iii) a particle diameter of 1 μm or more; (iv) a pore diameter of 20 nm or more; and (v) a cumulative pore volume in a pore diameter range of 40 nm to 1000 nm of more than 0.32 mL/g and 4 mL/g or less.

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An aluminum nitride particle including: a plurality of planes randomly arranged in a surface of the particle, the plurality of planes forming an obtuse ridge part or an obtuse valley part in the surface of the particle, the plurality of planes being observable in a scanning electron micrograph with 500 times magnification; wherein the particle has a longer diameter L of 20 to 200 μm; a ratio L/D of the longer diameter L (unit: μm) to a shorter diameter D (unit: μm) of the particle is 1 to 1.25; and the plurality of planes comprise a first plane, wherein an area S (unit: μm.sup.2) of the first plane satisfies S/L≥1.0 μm.

A composite pigment containing a substrate particle and a pigment layer arranged on a surface of the substrate particle, wherein the pigment layer contains a pigment, a resin and a metal oxide, and the metal oxide contains at least one selected from the group consisting of a silicon oxide, a polysiloxane, and composites thereof.

A composite pigment containing a substrate particle and a pigment layer arranged on a surface of the substrate particle, wherein the pigment layer contains a pigment, a resin and a metal oxide, and the metal oxide contains at least one selected from the group consisting of a silicon oxide, a polysiloxane, and composites thereof.

A method for producing silicon-containing oxide-coated aluminum nitride particles including aluminum nitride particles and a silicon-containing oxide coating covering a surface of each of the aluminum nitride particles. The method includes a first step including mixing aluminum nitride particles and an organic silicone compound solution in which an organic silicone compound containing a specific structure is dissolved in a solvent to form a mixture and then heating the mixture to remove the solvent and to obtain aluminum nitride particles coated with the organic silicone compound; and a second step including heating the aluminum nitride particles coated with the organic silicone compound at a temperature of 300° C. or more and 1,000° C. or less.

A method for producing silicon-containing oxide-coated aluminum nitride particles including aluminum nitride particles and a silicon-containing oxide coating covering a surface of each of the aluminum nitride particles. The method includes a first step including mixing aluminum nitride particles and an organic silicone compound solution in which an organic silicone compound containing a specific structure is dissolved in a solvent to form a mixture and then heating the mixture to remove the solvent and to obtain aluminum nitride particles coated with the organic silicone compound; and a second step including heating the aluminum nitride particles coated with the organic silicone compound at a temperature of 300° C. or more and 1,000° C. or less.