The present invention relates to transparent, electrically semiconducting interference pigments having high color strength, and in particular to flake-form interference pigments which comprise an oxygen-deficient layer of TiO.sub.2-x, to a process for the preparation of such pigments, and to the use of the pigments prepared in this way.

The present invention relates to gold-colored effect pigment including a nonmetallic substrate in platelet form and a coating applied thereto, wherein the coating includes at least one spacer layer. The invention further relates to a process for production of and to the use of the gold-colored effect pigment.

A product including ultrafine natural glass, methods of producing the ultrafine natural glass, and methods of use thereof are provided. The product may have, for example, a small top cut (d.sub.99) particle size of, for example, less than 12 microns. The product may also have high blue light brightness higher than, for example, 69, and/or low oil absorption, for example, less than 100 percent in volume. The product may be used in a variety of applications, such as, for example, anti-block filler in plastic films and/or reinforcement filler in polymers.

A composition including a first color shifting pigment having a first color shift that extends from a starting color at normal through a plurality of colors as a viewing angle is increased to a final color, wherein the first color shift rotates counterclockwise relative to, and about, an origin of the L*a*b* color space; and a color filter that transmits a portion of the first color shift of the first color shifting pigment and absorbs a remainder of the first color shift of the first color shifting pigment; wherein the composition has a second color shift different from the first color shift; and wherein the second color shift has a first portion that rotates counterclockwise relative to the origin and a second portion that rotates clockwise relative to the origin is disclosed. A security device including the composition is included. A method of making the composition and a method of authenticating the security device are also disclosed.

The invention relates to an absorbent effect pigment including a nonmetallic substrate in platelet form and a coating applied thereto, wherein the coating includes at least one spacer layer. The invention further relates to a process for production of and to the use of the absorbent effect pigment.

The invention relates to a transparent effect pigment which includes a non-metallic platelet-shaped substrate and a coating applied thereto, wherein the coating has a spacer layer. The invention further relates to a method for the production, as well as the use, of the transparent effect pigment.

The present invention relates to red effect pigments including a nonmetallic substrate in platelet form and a coating applied thereto, wherein the coating includes at least one of metal oxide, metal hydroxide or metal oxide hydrate, the metal ions of the metal oxide, metal hydroxide and/or metal oxide hydrate comprise at least two different metal ions selected from the group of metals consisting of Fe, Sn, Ti and Zr, and to a process for production thereof and to the use of the red effect pigments.

A method for simultaneously preparing an iron oxide red pigment and an aromatic amine is provided. In the method, an aromatic nitro compound and ferrous iron are first used to prepare an iron oxide red seed crystal under the action of a catalyst, and then iron powder is used to reduce the aromatic nitro compound and generate iron oxide in situ which grows into iron oxide red with pigment performance on the seed crystal. The method provides a clean and economical way for the reduction of an aromatic nitro compound (especially those in which there are other easily-reduced substituents on an aromatic ring) to prepare an aromatic amine.

Natural amorphous silica filler products featuring high brightness, low oil absorption, fine particle size, and low crystalline silica content are described. Methods for making, using, and measuring the properties of the natural amorphous silica filler products are also described. The natural amorphous silica filler products described herein may be useful in a variety of products including, but not limited to, polymers, sealants, paints, caulks, latex, architectural coatings, industrial coatings, pozzolan, glass catalysts, ceramic glazes, and anti-blocking applications.

Nontoxic Near infra-red Reflecting (NIR) inorganic pigments, characteristically blue and well suited for the coloration of a wide variety of substrates, for example, plastics and concrete building roofing material, etc., comprise mixed metal silicate having the general formula: La.sub.xSr.sub.1-xCu.sub.1-yLi.sub.ySi.sub.4O.sub.10, where x is equal to 0 to 0.5 and y is equal to 0 to 0.5. These silicates with tetragonal crystal structure are prepared by calcination method in air atmosphere.