The present invention relates to silver-coloured effect pigments having a strong sparkle effect based on Al2O3 flakes and to the use thereof in paints, button pastes, automotive paints, automotive refinish paints, powder coatings, printing inks, security printing inks, plastics, ceramic materials, glasses, paper, for coating seed, in security applications, as dopant for the laser marking of plastics and papers, as additive for the laser welding of plastics, in cosmetic formulations and for the preparation of pigment preparations and dry preparations.

The invention relates to a matting agent comprising agglomerates of pigment particles, to a method for the preparation of such matting agents, and to coating formulations containing the matting agents disclosed herein. The present invention further relates to pigmented mat surfaces, and to the use of agglomerates of pigment particles for matting pigmented coatings.

A wetting agent according to Formula (I):

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wherein R.sup.1 is selected from a branched alkyl group or linear alkyl group or a cycloaliphatic group or an aromatic group, each having 6 to 15 carbon atoms; R.sup.2 is selected from hydrogen, methyl, or ethyl; R.sup.3 is selected from hydrogen, methyl, or ethyl; R.sup.4 is selected from hydrogen, methyl, or ethyl; R.sup.5 is selected from methyl or ethyl; x ranges from 0 to 5; y ranges from 0 to 10; z ranges from 1 to 10; with the proviso that when x ranges from 1 to 5, R.sup.2 is different from R.sup.3; and with the proviso that when x=0, R.sup.3 is different from R.sup.4. The wetting agent also imparts anti-foam properties to aqueous solutions while reducing surface tension.

The invention provides a method for preparing a titanium dioxide product, comprising the steps of: providing a dispersion comprising titanium dioxide particles, wherein the dispersion contains from 50 g/l to 600 g/l TiO.sub.2;
and then, in any order, applying an inorganic coating to the titanium dioxide particles, whilst maintaining colloidal stability before and/or during the coating step; concentrating the dispersion, by subjecting the dispersion to the effects of cross-flow filtration and continuing the cross-flow filtration process until the dispersion is in a concentrated form that contains 800 g/l or more TiO.sub.2; so as to provide a titanium dioxide product in the form of a concentrated dispersion of coated particles.
The concentrated dispersion of coated particles may optionally be dispersed within a vehicle to obtain a pigment product.

A pigment grind dispersion contains non-adsorbed titanium dioxide particles dispersed in an aqueous emulsion containing a mixture of (a) water-insoluble film-forming first polymer particles that adsorb to titanium dioxide particles, the first polymer particle amount in the emulsion being less than the saturation level of adsorption when another polymer is not present, (b) water-insoluble film-forming second polymer particles that do not by themselves form composite particles with titanium dioxide particles, the second polymer particle amount in the emulsion being sufficient to inhibit or interfere with adsorption of the first polymer particles to titanium dioxide particles, and (c) extender particles. The pigment grind dispersion has a titanium dioxide pigment volume concentration of about 25 to about 50 and a titania composite ratio of about 32 to about 60.

A stable aqueous dispersion including certain composite particles and a method for forming the stable aqueous dispersion is provided. The composite particles include a pigment particle, the pigment particle having disposed thereon a certain water-soluble polymer including copolymerized carboxylic acid monomer and N-containing monomer and the pigment particle bearing the water-soluble polymer having disposed on it a plurality of water-insoluble polymer particles. Also provided is a dry coating formed from the aqueous dispersion.

Disclosed herein is an aqueous colloidal titanium dioxide dispersion preferably having a pH value in a range of 6.2 to 7.8 at 25 C. and including titanium dioxide particles, the titanium particles having a Z-average particle size in a range from 30 nm to 220 nm as determined by dynamic light scattering and a particle size distribution span [(D90-D10)/(D50)] in a range from 0.7 to 1.5; one or more dispersing agents comprising groups which bind to the titanium dioxide particles; one or more organic solvents; and if necessary, one or more pH value adjusting compounds. Further disclosed herein are a method of preparing such dispersions, a coating composition containing the components of such dispersions, coated substrates and methods of coating the substrates with such dispersions and a method of using of the dispersions in the manufacture of coating compositions.

The present disclosure is directed to compositions having lecithin and an organic acid and related methods. The disclosed compositions may also include one or more co-surfactants such as anionic surfactants and/or non-ionic surfactants, and may be used as a dispersant.

A pigment dispersion liquid includes a pigment dispersant; and a pigment, in which the pigment dispersant is a graft type silicone polymer denoted by General Formula 1. In General Formula 1, R.sup.1 to R.sup.10, R.sup.15 and R.sup.16 represent a hydrogen atom, a hydroxy group, an aryl group, or an alkyl group having 1 to 3 carbon atoms; R.sup.11 and R.sup.12 represent an arylene group or an alkylene group having 1 to 3 carbon atoms; Y and Z represent a single bond or a divalent organic linking group; A represents a group having a pigment adsorption portion; B represents a group having a structure denoted by General Formula 2; 1 and n represent an integer of greater than or equal to 1; m represents an integer of greater than or equal to 0; and k represents an integer of greater than or equal to 1.

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The present invention may provide talc calciner systems and methods to produce better and more efficient products by engineering a* and b* values for calcinated products perhaps by processing low iron talc in an indirectly heated, multiple zoned calciner which may progressively heat the feed supply at perhaps specifics residence times to produce a desired product.