Pigment for paper and paper laminate
AssigneeCristal USA Inc.
InventorsNeil Burniston, Robert Burniston
Life of this patent
Estimating the term…
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.
Claims15
A pigment mixture comprising (a) pigment particles having a mean primary particle size in the range of from about 0.15 micron (μm) to about 0.5 μm, (b) a hydrous metal oxide top coating on surfaces of the pigment particles, (c) colloidal spacer particles embedded in the top coating on the surfaces of the pigment particles, and (d) diatomaceous earth carrier particles, wherein the coated pigment particles with colloidal spacer particles are attached to surfaces of the diatomaceous earth carrier particles.
A pigment mixture comprising titanium dioxide pigment particles having a mean primary particle size in a range of from about 0.15 μm to about 0.5 μm, colloidal silica spacer particles, diatomaceous earth carrier particles having a mean primary particle diameter in the range of from about 2 to about 25 microns (μm), and an alumina top coating bonding the colloidal silica spacer particles to the pigment particles, wherein the pigment particles with colloidal spacer particles are combined with the diatomaceous earth carrier particles before the top coating is dried, or the pigment particles with colloidal spacer particles and the diatomaceous earth carrier particles are micronized together, or both, such that the top coated pigment with spacer particles are attached to surfaces of the carrier particles.
A cellulose-based product comprising cellulosic fiber and a pigment mixture including pigment particles having a mean primary particle size in a range of from about 0.15 μm to about 0.5 μm, colloidal spacer particles and diatomaceous earth 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, the carrier particles having a mean primary particle diameter in the range of from about 2 to about 25 microns (μm), the pigment mixture further comprising a top coating covering surfaces of the carrier particles, dispersed pigment and colloidal spacer particles, the top coating bonding the colloidal silica spacer particles to the pigment particles, the top coated pigment with spacer particles attached to surfaces of the carrier particles.
A cellulose-based product comprising cellulosic fiber and a pigment mixture including TiO2 pigment particles having a mean primary particle size in a range of from about 0.15 μm to about 0.5 μm, colloidal silica spacer particles, and diatomaceous earth carrier particles, wherein the colloidal silica spacer particles are dispersed on the surfaces of the TiO2 pigment particles, and the TiO2 pigment particles with spacer particles are dispersed on surfaces of the carrier particles, the carrier particles having a mean primary particle diameter in the range of from about 2 to about 25 microns (μm), the pigment mixture further comprising an alumina-containing top coating covering surfaces of the carrier particles with dispersed pigment and colloidal spacer particles, the top coating bonding the colloidal silica spacer particles to the pigment particles, the top coated pigment with spacer particles attached to surfaces of the carrier particles.
Dependencies are inferred from the claim text.