Pigment For Paper And Paper Laminate
AssigneeMillennium Inorganic Chemicals, Inc.
InventorsNeil Burniston, Robert Burniston
Life of this patent
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Abstract
A pigment mixture comprising (a) pigment particles, (b) colloidal spacer particles dispersed on surfaces of the pigment particles, and (c) carrier particles, wherein the pigment particles with colloidal spacer particles are dispersed on surfaces of the carrier particles. A pigment mixture of titanium dioxide pigment particles having colloidal silica spacer particles on surfaces of the titanium dioxide, the titanium dioxide and colloidal silica attached to surfaces of diatomaceous earth carrier particles, provides improved optical efficiency of the pigment and improved retention in a paper fiber matrix.
Claims22
A pigment mixture comprising (a) pigment particles, (b) colloidal spacer particles dispersed on surfaces of the pigment particles, and (c) carrier particles, wherein the pigment particles with colloidal spacer particles are dispersed on surfaces of the carrier particles.
A pigment mixture comprising titanium dioxide pigment particles, colloidal silica spacer particles, and diatomaceous earth carrier particles having a mean primary particle diameter in the range of from about 2 to about 25 microns (μm), wherein the colloidal spacer particles are dispersed on surfaces of the pigment particles, the pigment and spacer particles have an alumina top coating, and the top-coated pigment with spacer particles are dispersed on surfaces of the carrier particles.
A method of making a pigment mixture, comprising the steps of:
- (a) mixing a slurry of TiO2 pigment particles with colloidal spacer particles in a manner to cause the colloidal spacer particles to disperse onto surfaces of the pigment particles in an amount in the range of from about 0.1% to about 20% based on the weight of pigment particles;
- (b) precipitating a hydrous metal oxide selected from the group consisting of alumina, silica, phosphate and mixtures thereof to form a top coating on surfaces of the TiO2 pigment particles and colloidal spacer particles from step (a);
- and
- (c) mixing carrier particles having a mean primary particle diameter in the range of from about 2 to about 25 microns (μm) with the top coated TiO2 pigment and colloidal spacer particles from step (b) in a manner to form a pigment mixture having the pigment and colloidal spacer particles dispersed onto surfaces of the carrier particles in an amount in the range of from about 0.1% to about 20% based on the total weight of pigment, spacer and carrier particles.
A cellulose-based product comprising cellulosic fiber and a pigment mixture including pigment particles, colloidal spacer particles and carrier particles, wherein the colloidal spacer particles are dispersed on surfaces of the pigment particles, and the pigment particles are dispersed on surfaces of the carrier particles having a mean primary particle diameter in the range of from about 2 to about 25 microns (μm).
A cellulose-based product comprising cellulosic fiber and a pigment mixture including TiO2 pigment particles, colloidal silica spacer particles and carrier particles, wherein the colloidal silica spacer particles are dispersed on surfaces of the TiO2 pigment particles, the TiO2 pigment and colloidal silica spacer particles have a top coating of alumina, and the top coated TiO2 pigment particles with spacer particles are dispersed on surfaces of the carrier particles having a mean primary particle diameter in the range of from about 2 to about 25 microns (μm).
Dependencies are inferred from the claim text.