Provided is a dendritic silver-coated copper powder which is prevented from agglomeration, while ensuring excellent electrical conductivity by increasing contact points in cases where silver-coated dendritic copper powder particles are in contact with each other. This dendritic silver-coated copper powder is suitable for use in conductive pastes, electromagnetic shielding materials and the like. A dendritic silver-coated copper powder 1 according to the present invention has a dendritic form which comprises a linearly grown main trunk 2 and a plurality of branches 3 arising from the main trunk 2. The main trunk 2 and the branches 3 are configured of copper particles which have plate-like shapes having an average cross-sectional thickness of 0.2-1.0 μm, and the surfaces of which are coated with silver. This dendritic silver-coated copper powder 1 has an average particle diameter (D50) of 5.0-30 μm as determined by a laser diffraction/scattering particle size distribution measuring method.

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 m.sup.2/g to 50 m.sup.2/g.

Vanadium oxide nanomaterials dispersed in a polymeric matrix, substrates including the vanadium oxide nanomaterials dispersed in a polymeric matrix, and related methods of making vanadium oxide nanomaterials dispersed in a polymeric matrix are described.

There is provided a core-shell composite comprising a core which comprises zinc metal and a shell that at least partially encapsulates the core, wherein the shell comprises a salt of the zinc metal as a cation with a sulphur-containing anion. There is also provided a method of forming a core-shell composite comprising the step of heating a mixture of zinc metal particle with elemental sulphur to form the core-shell composite, wherein the zinc metal particle forms the core of the core-shell composite, and wherein the shell of the said core-shell composite at least partially encapsulates the core and comprises a salt of the zinc metal as a cation with a sulphur-containing anion. There is also provided a method of killing or inhibiting the growth of a microbe, comprising the step of subjecting the microbe to the as-disclosed core-shell composite. There is also provided an anti-microbial coating on a substrate surface or an additive in a composition or a formulation comprising the as-disclosed core-shell composite.

The invention relates to methods for producing coloured materials with the use of metal nanoparticles of gold, copper or silver, to said coloured materials, and to the uses of same in various applications.

The present invention relates to spherical, dense micrometre-sized particles comprising colourants. The invention also relates to a material comprising these particles intended for use in papermaking, paint, agri-food, cosmetics or pharmaceuticals. It also relates to the process for preparing these particles and their incorporation in a matrix.

The present invention discloses a rare-earth sulfide colorant and a preparation method thereof. The chemical formula of the rare-earth sulfide colorant of the present invention is RE.sub.2-2xS.sub.3-3x.2y [REPO.sub.4], wherein RE is selected from one or more of La, Ce, Pr, Nd and Sm, and the ratio of y to x is 0.001 to 0.65. The present invention also discloses use of a phosphorus-containing compound for increasing the vividness of a rare-earth sulfide colorant.

The present invention discloses a rare-earth sulfide colorant and a preparation method thereof. The chemical formula of the rare-earth sulfide colorant of the present invention is RE.sub.2-2xS.sub.3-3x.2y [REPO.sub.4], wherein RE is selected from one or more of La, Ce, Pr, Nd and Sm, and the ratio of y to x is 0.001 to 0.65. The present invention also discloses use of a phosphorus-containing compound for increasing the vividness of a rare-earth sulfide colorant.

A method of producing efficiently and stably core-shell type oxide particles, wherein the entire surface of the core oxide particles is uniformly coated with the shell oxide, includes at least two steps of: Step 1 of precipitating the core oxide particles in a mixed fluid prepared by mixing an oxide raw material liquid for core and an oxide precipitation solvent and Step 2 of coating the entire surface of the core oxide particles uniformly with the shell oxide by mixing the mixed fluid and an oxide raw material liquid for shell. (A) At least Steps 1 and 2 are performed continuously between at least two processing surfaces 1 and 2 which are capable of approaching to and separating from each other, at least one of which rotates relatively to the other; (B) after Step 1, Step 2 is completed within a prescribed time during which the core oxide particles do not aggregate in the mixed fluid; or (C) Step 1 and Step 2 are controlled so that the primary particle diameter of the core-shell type oxide particles is 190% or less relative to the primary particle diameter of the core oxide particles.

Core particles produced in situ or introduced as preformed core particles are coated with a layer of carbon. Non-carbon as well as some carbon-based core materials can be utilized. The resulting carbon coated particles can find applications in rubber products, for instance as reinforcement for tire components.