Ecc America Inc.

Ecc International Limited

E Wayne Andrews

Rasik H Raythatha

Alan J Brown

Dickey S Shurling

Paul R Suitch

An improved process for producing a aggregated kaolin pigment having desired physical and optical characteristics when used as a coating, filler or pigment in paper. The aggregated pigment is produced by contacting a substantially dry fine particle size kaolin with a previously hydrolyzed organic silicon compound, such as hydrolyzed tetraethoxysilane, and then recovering the aggregated kaolin pigment.

Method of producing aggregated kaolinite pigment using organic silicon

An improved process for producing a aggregated kaolin pigment having desired physical and optical characteristics when used as a coating, filler or pigment in paper. The aggregated pigment is produced by mixing an aqueous slurry of a fine particle kaolin with a previously hydrolyzed organic silicon compound, such as hydrolyzed tetraethoxysilane, and then spray drying the mixture to form a dry, chemically aggregated kaolin pigment.

A method is provided for reducing the abrasiveness of calcined clay, e.g., kaolin clay. The method comprises intermixing the clay prior to calcination with a finely-divided silica, preferably in the form of colloidal or fumed silica, in an amount sufficient to reduce the abrasiveness of the calcined product.

Method for reducing the abrasion of calcined clay

The invention relates to a structured kaolinitic pigment having improved physical and optical characteristics when incorporated as a filler or coating pigment in paper. The pigment consists of porous aggregates of kaolin particles which are chemically bonded together. The pigment may be produced by chemically reacting a particulate kaolin with a metal chloride, such as silicon tetrachloride, and with urea or an organic amine. The process is conducted under conditions such that the kaolinite structure is not altered.

Structured kaolin pigments

A process is described in which a structured aggregated kaolin pigment is prepared by mixing substantially dry kaolin in particulate form with an aqueous alkali metal silicate to deposit on the surface of the kaolin particles a substantially molecular level of said silicate without formation of silica gel, drying the treated kaolin without calcination and exposing it to an acidic gas. The product is useful as a pigment in the coating or filling of paper.

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Sandersville, GA, United States of America

E Wayne Andrews