Provided is a filler that has a low viscosity when mixed in a resin material and has reduced permittivity and dielectric loss tangent. The filler includes: a metal oxide particle material; and a polyorganosiloxane compound with which a surface treatment is performed on the metal oxide particle material and which is represented by general formula (1): (RO).sub.3Si—(SiR.sub.2—O—).sub.n—SiR.sub.3 (in general formula (1), each R is independently selected from among alkyl groups having 1 to 4 carbon atoms, and n is not less than 10 and not greater than 200). A resin composition obtained by containing the filler in a resin is suitable for an electronic material.

An object is to reduce the occurrence of aggregation of an inorganic pigment that roughens the texture and dulls the color of a cosmetic containing the inorganic pigment. Porous pigment particles are provided which include cellulose or a cellulose derivative, and an inorganic pigment as main components. Also provided are a method for producing such particles, and a cosmetic containing such porous pigment particles. The particles are resistant to aggregation and are excellently dispersed in a base material to impart a color while improving the dullness problem. The particles of the present invention are porous particles that contain cellulose and have a wrinkle-like or fold-like uneven structure on the surface thereof (that is, have an appropriate amount of pores or voids). Thus, the particles of the present invention have soft and comfortable texture and are suitably added to cosmetics that are directly applied to the skin.

A dispersion liquid contains an inorganic oxide particle surface-treated with at least one of a compound represented by Formula Si(R.sup.A1)(X.sup.A1).sub.3 or a compound represented by Formula Si(R.sup.A2)(R.sup.A20)(X.sup.A2).sup.2, polysiloxane having at least one of a T unit represented by Formula [R.sup.B1SiO.sub.3/2] or a D unit represented by Formula [R.sup.B2R.sup.B20SiO], and an organic solvent, where a content of the polysiloxane is 0.5% to 39% by mass with respect to a total amount of the inorganic oxide particle and the polysiloxane, in which in the formula, R.sup.A1, R.sup.A2, R.sup.B1, and R.sup.B2 represent a functional group, X.sup.A1 and X.sup.A2 represent a hydroxyl group or a hydrolyzable group, and R.sup.A20 and R.sup.B20 represent an alkyl group or an aryl group.

A filler composition is excellent in heat dissipation. A silicone resin composition includes the filler composition. A heat dissipation element is made by molding the silicone resin composition. More specifically, the filler composition has a filler (A1) having an average particle diameter of 0.3-1.0 μm, a filler (A2) having an average particle diameter of 3-15 μm, and a filler (A3) having an average particle diameter of 35-140 μm, wherein the filler (A1), the filler (A2) and the filler (A3) are one or more kinds selected from alumina, magnesia, AlN covered alumina, AlN and SN.

A cutting wheel includes a body having a bond material. The bond material comprises at least about 31 vol % of a total volume of the body. Additionally, the body includes abrasive particles contained within the bond material. The abrasive particles include a first type of abrasive particle including black alumina with at least about 10 vol % of a total volume of the abrasive particles including black alumina. In some instances the cutting wheel can include a chop saw, while in other situations, the cutting wheel can include a cut-off wheel.

To provide plate-like alumina particles that are less likely to wear apparatuses. Plate-like alumina particles containing germanium or a germanium compound. The plate-like alumina particles preferably have a molar ratio of Ge to Al, [Ge]/[Al], of 0.08 or more as determined in an XPS analysis. The plate-like alumina particles preferably contain the germanium or germanium compound in a surface layer. The plate-like alumina particles preferably have a density of 3.7 g/cm.sup.3 or more and 4.1 g/cm.sup.3 or less. The plate-like alumina particles preferably have a molar ratio of Ge to Al, [Ge]/[Al], of 0.08 or less as determined in an XRF analysis.

A method of producing new hydrophobic aluminas by i) providing a slurry comprising an alumina compound, the slurry having a pH of above 5.5; ii) mixing an organic composition comprising carboxylic acids with long hydrocarbon chains with the slurry to form an acid modified slurry; iii) hydrothermally conditioning the acid modified slurry to form a hydrothermally aged slurry; and iv) drying the hydrothermally aged slurry. The new hydrophobic aluminas have surface modified structures distinguished by a low humidity content and very small nanoparticles. These new hydrophobic aluminas can be uniformly dispersed in a substrate, for example polymers.

A method of producing a hydrophobic porous alumina by: i) providing a slurry comprising an alumina compound, the slurry having a pH equal to or greater than 7; ii) adding an organic composition comprising carboxylic acids with alkyl hydrocarbon chains having a carbon length less than 14 to the slurry to form an acidic modified slurry; the acidic modified slurry having a pH of between 3 and less than 7; iii) hydrothermally aging the acidic modified slurry to form a hydrothermally aged slurry; and iv) drying the hydrothermally aged slurry.

Provided is a filler that has a low viscosity when mixed in a resin material and has reduced permittivity and dielectric loss tangent. The filler includes: a metal oxide particle material; and a polyorganosiloxane compound with which a surface treatment is performed on the metal oxide particle material and which is represented by general formula (1): (RO).sub.3Si—(SiR.sub.2—O—).sub.n—SiR.sub.3 (in general formula (1), each R is independently selected from among alkyl groups having 1 to 4 carbon atoms, and n is not less than 10 and not greater than 200). A resin composition obtained by containing the filler in a resin is suitable for an electronic material.

The present invention discloses the morphology of hollow, double-shelled submicrometer particles generated through a rapid aerosol-based process. The inner shell is an essentially hydrophobic carbon layer of nanoscale dimension (5-20 nm), and the outer shell is a hydrophilic silica layer of approximately 5-40 nm, with the shell thickness being a function of the particle size. The particles are synthesized by exploiting concepts of salt bridging to lock in a surfactant (CTAB) and carbon precursors together with iron species in the interior of a droplet. This deliberate negation of surfactant templating allows a silica shell to form extremely rapidly, sealing in the organic species in the particle interior. Subsequent pyrolysis results in a buildup of internal pressure, forcing carbonaceous species against the silica wall to form an inner shell of carbon. The incorporation of magnetic iron oxide into the shells opens up applications in external stimuli-responsive nanomaterials.