Abstract: The invention relates to a pearl luster pigment which may possess a first, inner layer, consisting of a platelet-shaped substrate, a second layer, comprising one or more metal oxides, the first and second layers forming a calcined base pigment, a third layer, comprising the corresponding uncalcined oxide, hydroxide or oxide hydrate of the oxide of the second layer, a fourth layer, comprising oxides, hydroxides and/or oxide hydrates of silicon or aluminum, a fifth layer, comprising oxides, hydroxides and/or oxide hydrates of silicon, aluminum, zirconium and/or cerium, this layer differing from the fourth layer, and a sixth layer, comprising one or more organofunctional coupling reagents. The present invention relates to also a preparation process, and the use of the pigments in paints, inks, plastics, coatings and cosmetics.

Abstract: The present invention relates to a pearl luster pigment on the basis of a platelet-shaped substrate coated with metal oxides and a top layer which is located on the metal oxide layer and can possess a multilayer structure, comprising a first layer, containing a hydroxide or oxide hydrate of the elements aluminum or silicon, a second layer, containing at least one hydroxide or oxide hydrate of the elements aluminum, silicon, cerium or zirconium, with the exception of the hydroxide or oxide hydrate which forms the first layer, and a third layer, containing at least one organic hydrophobic coupling agent. The present invention also relates to a preparation process and the use of pigments in paints, inks, plastics, coatings and cosmetics.

Abstract: The present invention provides new solid solutions having a corundum-hematite crystalline structure which are useful as inorganic color pigments. Solid solutions according to the present invention include a host component having a corundum-hematite crystalline structure which contains as guest components one or more elements from the group consisting of aluminum, antimony, bismuth, boron, chrome, cobalt, gallium, indium, iron, lanthanum, lithium, magnesium, manganese, molybdenum, neodymium, nickel, niobium, silicon, tin, titanium, vanadium, and zinc. Solid solutions according to the present invention are formed by thoroughly mixing compounds, usually metal oxides or precursors thereof, which contain the host and guest components and then calcining the compounds to form the solid solutions having the corundum-hematite crystalline structure. Some of the new solid solutions according to the present invention exhibit relatively low Y CIE tri-stimulus values and relatively high near infrared reflectance.

Abstract: Cartridges useful in regenerating or purifying dialysis solutions are described as well as methods to regenerate or purify spent dialysis solutions. Dialysis systems using the sorbent cartridges of the present invention are further described.

Abstract: Moldings are disclosed for use as a catalyst or catalyst support for hydrating olefin, such as ethylene and propylene. The moldings are based on a pyrogenically produced mixed oxide having the following physicochemical parameters: External diameter 0.8-25 mm BET surface area 5-400 m2/g Pore volume 0.2-1.8 ml/g Fracture strength 5 to 350 N Composition At least two materials selected from the group of SiO2, Al2O3, TiO2 and ZrO2 in any desired combination, with the proviso that when the combination is a SiO2/Al2O3 mixed oxide, at least 75 wt. % of SiO2 is present based on the total weight of the mixed oxide. Other constituents <1 wt. % Bulk density 250-1500 g/l.

Abstract: The composition is based on a samarium sesquisulphide, it exhibits a samarium purity with respect to other rare earth metals of greater than 99% and it comprises at least one alkali metal or alkaline earth metal element, at least a portion of which is included in the crystal lattice of the said sesquisulphide. According to another embodiment, the composition is based on a sesquisulphide of samarium and of at least one rare earth metal which is solely trivalent and it comprises at least one alkali metal or alkaline earth metal element, at least a portion of which is included in the crystal lattice of the said sesquisulphide. According to a third embodiment, the composition exhibits a samarium purity such that the cerium content is less than 1%. The process consists in reacting samarium, trivalent rare earth metal and alkali metal or alkaline earth metal compounds with a gaseous mixture of hydrogen sulphide and of carbon disulphide.

Abstract: In a method of manufacturing a gold containing pigment, a vaporizable gold compound, a vaporizable compound of another metal, which includes an oxide or a nitride with a melting temperature above the melting temperature of gold, and a reaction gas consisting of a mixture of argon and oxygen are introduced into a first microwave plasma, whereby cores covered with gold clusters are formed from the oxide or nitride and the gold cluster covered cores are subjected to a tempering process at 150° C. to 300° C. for causing coloration of the gold cluster covered oxide or nitride cores.

Abstract: A flake-based pigment is provided having improved specular reflectance characteristics in the visible wavelength range. The flake-based pigment has a plurality of core flake sections each formed of a central reflector layer and dielectric support layers on opposing sides of the reflector layer. The resulting core flake section is a very thin three-layered structure that exhibits a uniaxial compressive strength much greater than a corresponding uniaxial tensile strength. This structure provides the benefits of rigidity and brittle fracture during manufacturing and application processes, which ultimately provides favorable planar and specular reflectance characteristics for the pigment in the visible wavelength range. A variety of outer coating layers can be formed around the core flake sections, such as various dielectric and absorber layers having thicknesses dependent upon the desired optical characteristics of the pigment.

Abstract: A flake-based pigment is provided having improved specular reflectance characteristics in the visible wavelength range. The flake-based pigment has a plurality of core flake sections each formed of a central reflector layer and dielectric support layers on opposing sides of the reflector layer. The resulting core flake section is a very thin three-layered structure that exhibits a uniaxial compressive strength much greater than a corresponding uniaxial tensile strength. This structure provides the benefits of rigidity and brittle fracture during manufacturing and application processes, which ultimately provides favorable planar and specular reflectance characteristics for the pigment in the visible wavelength range. A variety of outer coating layers can be formed around the core flake sections, such as various dielectric and absorber layers having thicknesses dependent upon the desired optical characteristics of the pigment.

Abstract: A pigment composition for use as a substrate to produce ink, paints, and pigment compounds, the composition being made from an aqueous slurry containing about 17 to 40% calcium carbonate, based on the weight of said aqueous slurry, and an inorganic pigment from group comprising titanium dioxide, in which the amount of calcium carbonate is higher than that found in standard pigment compositions and the amount of amount of pigment is lower than that found in standard pigment compositions, yet there is not an appreciable degradation of the color, coating, and other qualities of the pigment composition.

Abstract: A sol-gel process for producing layers of zirconium oxide is described which comprises the following stages:

Abstract: A zirconia sol comprising an aqueous phase having dispersed therein a plurality of single crystal zirconia particles having an average primary particle size less than about 20 nm. The zirconia sols are substantially non associated having a dispersion index ranging from about 1-3 and are highly crystalline exhibiting a crystallinity index of about 0.65 or greater. Of the crystalline phase, about 70% or greater exists in combined cubic and tetragonal crystal lattice structures without a crystal phase stabilizer. Also described is a hydrothermal method of making zirconia sols having substantially non-associated zirconia particles and composite materials made from the zirconia sols.

Abstract: A ceramic welding process for the formation of a coherent refractory repair mass on a surface of an electrocast refractory material includes providing an electrocast refractory material having a surface to be repaired; providing a first powder mixture comprised of combustible particles, refractory particles, and at least one constituent which enhances production of a vitreous phase in the coherent refractory repair mass; and projecting the first powder mixture in a gas stream containing oxygen against the surface to be repaired so that the combustible particles react with the projected oxygen against the surface in a highly exothermic manner and release sufficient heat of combustion to form a first coherent refractory repair mass.

Abstract: The present invention provides a coated titanium dioxide pigment which includes a base titanium dioxide pigment; a first deposit of a phosphate compound contiguous with the base titanium dioxide pigment; a deposit of a silica or zirconia compound contiguous with the phosphate deposit; a second deposit of a phosphate compound contiguous with the silica or zirconia compound; and a deposit of an alumina compound contiguous with the second phosphate deposit. Titanium dioxide pigments of the present invention are easily dispersible, and display excellent durability and gloss.

Abstract: The invention relates to a highly orientated flaky pigment being excellent in plane orientation (leafing effect), wherein a hydrated metal oxide and one or more fluorine-containing phosphates represented by the general formulae (A) and (B) shown in below or salts thereof are covered on the surface of a flaky pigment with a pearl gloss. The general formulae: (A) (RfCnH2nO)mPO(OM)3−m (B) (RfSO2NRCnH2nO)mPO(OM)3−m wherein Rf is the same or different and represents linear or branched C3 to C21 perfluoroalkyl group or perfluoroxyalkyl group, n is 1 to 12, m is 1 to 3, M represents hydrogen, alkali metal, ammonium group or substituted ammonium group, and R represents hydrogen or C1 to C3 alkyl group. A process for producing said pigment in a wet process is also disclosed.

Abstract: An umber paint, which is excellent in transparency and heat resistance, and which does not bring about environmental pollution, bulbs coated with the umber paint, and turn signal lams equipped with the bulbs. The umber paint, for turn signal lamps, contains at least a red pigment 10a and a yellow pigment 10b, wherein the yellow pigment comprises acetylacetone metal chelateumber.

Abstract: A pigment dispersion comprising pigment, an aqueous carrier selected from water and a mixture of water and at least one organic solvent, and a pigment dispersant is described. The pigment dispersant is prepared by polymerizing (i) at least one prepolymer having a radically polymerizable group, and (ii) at least one second monomer. The prepolymer is prepared by controlled radical polymerization, e.g., atom transfer radical polymerization, of at least one radically polymerizable first monomer. The second monomer forms a polymeric backbone segment of the pigment dispersant, and the prepolymer forms polymeric segments that are pendent to the backbone. The backbone segment of the pigment dispersant is hydrophilic, while at least a portion of each pendent polymeric segment is hydrophobic.

Abstract: A pigment dispersion comprising pigment, an aqueous carrier selected from water and a mixture of water and at least one organic solvent, and a pigment dispersant is described. The pigment dispersant is prepared by controlled radical polymerization, e.g., atom transfer radical polymerization, of a radically polymerizable monomer in the presence of a polymeric initiator having at least one radically transferable group. The polymeric initiator forms the polymeric backbone segment of the pigment dispersant, and the monomer forms polymeric segments that are pendent to the polymeric backbone segment. The pigment dispersant has comb-like architecture in which the polymeric backbone segment is hydrophobic, and at least a portion of each pendent polymeric segment is hydrophilic.

Abstract: A universal tinting concentrate for both solvent- and water-based paints and coatings. The universal tinting concentrate is a composition which includes a colorant component, such as pigment, colorant, tinting agent and/or metal effect agent; a pigment dispersant including an organic acid containing no more an 70 carbon atoms; and a pH-neutralizing agent. In one embodiment of the invention, the pigment dispersant is represented by the following structure: where r and s are integers and r+s is 6 to 16; and x and y are integers and x+y is 0 to 19; and Z is H or COOH and Z′ is H or COOH.

Abstract: A film for cutting off heat rays having a high transmittance and a low reflectivity of visible light, a low transmittance and a high reflectivity of near infrared radiation and a surface resistivity of at least about 106 ohms/square is formed from a coating liquid is a dispersion containing fine particles of borides having an average diameter not exceeding 100 nm. The liquid disperison is coated on a surface and heated. The dispersion may further contain fine particles of at least one ruthenium or iridium oxide having an average diameter not exceeding 100 nm.

Abstract: In a method of manufacturing a gold containing pigment, a vaporizable gold compound, a vaporizable compound of another metal, which includes an oxide or a nitride with a melting temperature above the melting temperature of gold, and a reaction gas consisting of a mixture of argon and oxygen are introduced into a first microwave plasma, whereby cores covered with gold clusters are formed from the oxide or nitride and the gold cluster covered cores are subjected to a tempering process at 150° C. to 300° C. for causing coloration of the gold cluster covered oxide or nitride cores.

Abstract: Optical coating compositions containing thin film particulates or pigments that are capable of imparting to the coating preselected optical characteristics or properties, such as selective reflectance, transmission and absorptance of light energy, are comprised of film forming binder and improved high volume pigment particles dispersed in the binder. Each pigment particle is a high volume flake comprised of an inorganic or polymer core having two sides and a thin film optical structure deposited onto each of the two sides of the core. The core occupies a large volume of the coating composition and dramatically reduces the number of flakes and the amount of thin film structures required to produce a coating of given thickness and desired optical properties. The core may also be fabricated to have diffuse and irregular side surfaces in order to render the applied coating visually diffuse and nonspecular. Methods of making the pigment particles are disclosed.

Abstract: The present invention provides a process for the production of hydrophobic inorganic oxide products which comprises reacting the inorganic oxide particles with organohalosilanes, preferably organochlorosilanes, to produce hydrophobic organosilane coated inorganic oxides. It is preferred that the organohalosilane compounds be reacted with the inorganic oxide particles in an aqueous slurry and subjected to intense mixing. The inorganic oxide pigments prepared by the processes of this invention have essentially quantitative retention of the organosilanes and contain no adsorbed aldehydes on their surface. The by-products produced in the preferred embodiments of the invention are innocuous salts, which are environmentally safe and readily disposable.

Abstract: The iron oxide platelets comprise at least one layer packet comprising A) a colorless coating having a refractive index n≦1.8, and B) a colorless coating having a refractive index n≧2.0.

Abstract: A method of producing a low structure pyrogenic metal oxide filler is disclosed. The method involves subjecting pyrogenically produced metal oxide agglomerates and aggregates selected from silicon oxide, aluminum oxide, zirconium oxide, or titanium oxide to a dry milling process whereby the pyrogenically produced metal oxide is contacted in an agitating zone with an energy specific force.

Abstract: Modified pearl luster pigments for waterborn coating systems, based on a platelet-form substrate coated with metal oxides and, located on the topmost metal oxide layer, a top layer consisting of at least two oxides and/or mixed oxides from the group consisting of silicon dioxide, aluminium oxide, cerium oxide, titanium oxide and zirconium oxide, and on a water-based oligomeric silane system. The oligomeric silane system can be described, for example, by the following approximate structure: [HO[Si(A)(OH)z(CH3)1−zO]a[Si(B)(OH)y(CH3)1−yO]b[Si(E)(OH)w(CH3)1−wO]c[Si(D)(OH)v(CH3)1−vO]dH].

Abstract: Ceramic decoration coloring substances substantially containing a zirconium pigment of the host lattice or inclusion type and a glass flux at a pigment volume concentration (PVC) of at least 30% have an increased color saturation C* if the glass flux comprises at least 71 wt. % PbO. Preferred decoration coloring substances have a PVC in the range from 40 to 70% and a PbO content of 75 to 85 wt. %. The decoration coloring substances are especially suitable for production of decorations, burned at 1000 to 1250°C, with increased color saturation C*.

Abstract: The present invention provides new solid solutions having a corundum-hematite crystalline structure which are useful as inorganic color pigments. Solid solutions according to the present invention include a host component having a corundum-hematite crystalline structure which contains as guest components one or more elements from the group consisting of aluminum, antimony, bismuth, boron, chrome, cobalt, gallium, indium, iron, lanthanum, lithium, magnesium, manganese, molybdenum, neodymium, nickel, niobium, silicon, tin, titanium, vanadium, and zinc. Solid solutions according to the present invention are formed by thoroughly mixing compounds, usually metal oxides or precursors thereof, which contain the host and guest components and then calcining the compounds to form the solid solutions having the corundum-hematite crystalline structure. Some of the new solid solutions according to the present invention exhibit relatively low Y CIE tri-stimulus values and relatively high near infrared reflectance.

Abstract: A corrosion-inhibiting composition for application to a metal substrate, such as steel, silver, copper or aluminum, includes a film-forming organic polymer component and a dispersed pigment phase of a stable unitary hybrid which contains organic and inorganic solid phase constituents interfaced at a micro-crystalline level, which are inseparable by physical separation procedures and which display uniphase behavior. The inorganic phase includes a cation selected from Zn, Al, Mg, Ca, Sr, Ti, Zr, Ce and Fe and an anion selected from phosphates, polyphosphates, phosphites, molybdates, silicates and cyanamides.

Abstract: The present invention relates to inorganic pigment pellets for coloring building materials, lacquers and plastics and to a process for the production thereof and to the use thereof inter alia for the production of pastes, suspensions and emulsion paints.

Abstract: Composite pigments based on nanoparticulate metal oxides modified by crosslinked or uncrosslinked polyalkylenepolyamine and anionic dyes are useful for coloring paints, inks, plastic, paper, wood, leather and textile materials.

Abstract: The present invention relates to pigment preparations containing(a) at least one pigment having an average primary particle size of 0.1 to 50 nm selected from the group consisting of carbides, nitrides, borides, and silicides of the elements Ti, Zr, Hf, Si, Ge, and Sn,(b) at least one dispersant having a weight average molecular weight (M.sub.w) greater than 1000, and(c) water.The invention further relates to the use of such pigment preparations in inks for ink-jet printing.

Abstract: Metal oxide particles having a substantial uniform and homogeneous (across-particle) coating of a metal oxide or organofunctionalized metal oxide are disclosed and are prepared by hydrolysis of a monomeric precursor to the coating.

Abstract: Effective anti-corrosive pigments are obtained using basic or neutral to basic polyvalent metal organophosphonates. The anti-corrosive organophosphonate pigments may optionally contain a co-acidic substance such as silica. The organophosphonate pigments provide ant-corrosive protection comparable to traditional pigments while enabling the avoidance of heavy metals.

Abstract: A modified particle is disclosed wherein a particle has an attached group having the formula: ##STR1## wherein Ar represents an aromatic group; R.sup.1 represents a bond, an arylene group, an alkylene ##STR2## wherein R.sup.4 is an alkyl or alkylene group or an aryl or arylene group; R.sup.2 and R.sup.3, which can be the same or different, represent hydrogen, an alkyl group, an aryl group, --OR.sup.5, --NHR.sup.5, --NR.sup.5 R.sup.5, or --SR.sup.5, wherein R.sup.5, which is the same or different, represents an alkyl group or an aryl group; and SFR represents a stable free radical. Also disclosed is a modified particle or aggregate having attached a group having the formula: ##STR3## wherein CoupA represents a Si-containing group, a Ti-containing group, or a Zr-containing group; R.sup.8 and R.sup.9, which can be the same or different, represent hydrogen, an alkyl group, an aryl group, --OR.sup.10, --NHR.sup.10, --NR.sup.10 R.sup.10, or --SR.sup.10, wherein R.sup.

Abstract: The invention relates to a process for manufacturing decorated ceramic and glass articles according to which a ceramic dye composition, including fine particles which comprise ceramic pigments and binding medium resin(s) as well as possible further additives, is applied by means of an electrophotographic reproduction process onto a transfer means, for example paper coated with gum arabic, the transfer means coated with the ceramic dye composition is applied onto the ceramic or glass article, and after removal of the transfer means, the ceramic dye composition is combined with the ceramic or glass article by baking. The invention also includes decorative ceramic or glass articles obtainable by means of the above process and a ceramic dye composition of the type mentioned above.

Abstract: A stir-in pigment composition for coloring high-molecular-weight material, particularly coatings and ink systems, comprises 85 to 99.5 parts by weight of a pigment and 0.5 to 15 parts by weight of an additive comprising a vinylpyrrolidone polymer or copolymer. The stir-in pigment composition is in the form of microgranules and is obtainable by spray drying a high solids content aqueous pigment dispersion containing the pigment and the additive. The new pigment composition powders are easily handled, easily wetted and disperse rapidly to form homogeneous aqueous pigment dispersions which are practically free of larger pigment aggregates and can readily be incorporated into aqueous ink and paint systems as stir-in pigments without a dispersion step in a bead mill.

Abstract: Surface-modified, pyrogenically produced mixed oxides which contain two or more components of the series SiO.sub.2, Al.sub.2 O.sub.3, TiO.sub.2, ZrO.sub.2, Fe.sub.2 O.sub.3, Nb.sub.2 O.sub.5, V.sub.2 O.sub.5, WO.sub.3, SnO.sub.2, GeO.sub.2 and have been surface-modified with one to several compounds of the following groups:(a) organosilanes of the type (RO).sub.3 Si(C.sub.n H.sub.2n+1),(b) R'.sub.x (RO).sub.y Si(C.sub.n H.sub.2n+1),(c) X.sub.3 Si(C.sub.n H.sub.2n+1),(d) X.sub.2 (R')Si(C.sub.n H.sub.2n+1),(e) X(R').sub.2 Si(C.sub.n H.sub.2n+1),(f) (RO).sub.3 Si(CH.sub.2).sub.m --R',(g) (R").sub.x (RO).sub.y Si(CH.sub.2).sub.m --R',(h) X.sub.3 Si(CH.sub.2).sub.m --R',(i) (R)X.sub.2 Si(CH.sub.2).sub.m --R',(j) (R).sub.2 X Si(CH.sub.2).sub.m --R',(k) Silazanes of the type ##STR1## (l) Cyclic polysiloxanes, (m) Polysiloxanes or silicone oils.

Abstract: Disclosed is a system of natural colours consisting of thousands of coloured powders of mineral origin and of materials in or on which pigments have been applied and, afterwards, submitted to at least one thermal treatment and/or irradiation. These natural colours cover the totality of the visible spectrum and offer a great variety of tones, tints and reflections from white to black, including all the rainbow colours. The powders of this system are obtained by mechanical, chemical, thermal and/or physical processes and are used alone or in combination. They are particularly useful to colour materials and, more especially those used in the construction and architectural fields.

Abstract: Purple pigments according to the invention based on a stovable support material, in particular a glass frit, having a coat applied by coprecipitation of an oxide hydrate of one or more elements from the range comprising Al, Si, Sn, Pb, Ti, Nb, Ta, Sc, Y, La, Ce and Zn and a water-insoluble gold compound or colloidal gold are distinguished from prior art pigments of a similar composition by improved color stability in high temperature firing. The pigments are obtainable in the aqueous phase by coprecipitation of an oxide hydrate and a gold compound or colloidal gold in the presence of a support material and in the absence of a reducing agent. Pigments containing gold compounds assume a purple color on heat treatment or by chemical reduction. Preferred pigments containing gold compounds, which may directly be used as decorative colorants, conveniently develop their color during firing of the decoration.

Abstract: A ceramic composition for the repair of porous ceramic bodies comprises a ceramic material having cations which are reactive with phosphate ions, a source of reactive phosphate ions, and filler. An aqueous slurry of the ceramic composition is prepared and applied to the damaged region of a porous ceramic body. The slurry mixture is dried within the damaged region of the porous ceramic body and heated to bind the mixture together and to bond the mixture to the porous ceramic body within the damaged region. The method of the invention allows for the in situ repair of ceramic materials without removing them from their supporting structure and can be used in the repair of ceramic tiles for spacecraft and aircraft.

Abstract: Improved coated inorganic pigments having a first coating of Al.sub.2 O.sub.3, SiO.sub.2, or optionally other oxide such as a source of P.sub.2 O.sub.5, or mixtures thereof, an optional coating of ZrO.sub.2, SnO.sub.2, TiO.sub.2, SiO.sub.2, CeO.sub.2 or mixtures thereof, and a final coating of Al.sub.2 O.sub.3 which exhibit good durability, dispersibility, and optical properties in plastic or paint compositions are disclosed. Also disclosed is a process whereby an aqueous slurry of an inorganic pigment is milled to achieve a particular particle size distribution, a first coating of Al.sub.2 O.sub.3, SiO.sub.2, or optionally other oxide such as a source of P.sub.2 O.sub.5, or mixtures thereof is precipitated onto the pigment material within a first pH range, an optional amount of ZrO.sub.2, SnO.sub.2, SiO.sub.2, TiO.sub.2, CeO.sub.2 or mixtures thereof is added to the aqueous slurry within a second pH range to obtain an optional coating over the first coating, and a final coating of Al.sub.2 O.sub.

Abstract: The invention relates to granules of inorganic pigments, a process for their production using several auxiliary substances by compacting and their use in many technical fields.

Abstract: Goniochromatic luster pigments based on multiply coated, high refractive, nonmetallic, platelet-shaped substrates which are at least partially transparent to visible light, comprising at least one layer packet ofA) a colorless coating having a refractive index n.ltoreq.1.8 andB) a reflecting, selectively or nonselectively absorbing coating which is at least partially transparent to visible light,and also, if desired, additionallyC) an outer protective layer,and their use for coloring paints, inks, including printing inks, plastics, glasses, ceramic products and decorative cosmetic preparations.

Abstract: The invention relates to a process for manufacturing decorated ceramic and glass articles according to which a ceramic dye composition, including fine particles which comprise ceramic pigments and binding medium resin(s) as well as possible further additives, is applied by means of an electrophotographic reproduction process onto a transfer means, for example paper coated with gum arabic, the transfer means coated with the ceramic dye composition is applied onto the ceramic or glass article, and after removal of the transfer means, the ceramic dye composition is combined with the ceramic or glass article by baking. The invention also includes decorative ceramic or glass articles obtainable by means of the above process and a ceramic dye composition of the type mentioned above.

Abstract: Disclosed is a system of natural colors consisting of thousands of colored powders of mineral origin and of materials in or on which pigments have been applied and, afterwards, submitted to at least one thermal treatment and/or irradiation. These natural colors cover the totality of the visible spectrum and offer a great variety of tones, tints and reflections from white to black, including all the rainbow colors. The powders of this system are obtained by mechanical, chemical, thermal and/or physical processes and are used alone or in combination. They are particularly useful to color materials and, more especially those used in the construction and architectural fields.

Abstract: Disclosed is a system of natural colors consisting of thousands of colored powders of mineral origin and of materials in or on which pigments have been applied and, afterwards, submitted to at least one thermal treatment and/or irradiation. These natural colors cover the totality of the visible spectrum and offer a great variety of tones, tints and reflections from white to black, including all the rainbow colors. The powders of this system are obtained by a combination of two mechanical, chemical, thermal and/or physical processes and are used alone or in combination. They are particularly useful to color materials and, more especially those used in the construction and architectural fields.

Abstract: Spherical agglomerates of finely divided material such as inorganic oxides are prepared by admixing a slurry of finely divided material with a solution of a partially neutralised carboxylic acid.

Abstract: A treated inorganic solid comprises particulate inorganic material the particles of which are coated with an alkylphosphonic acid or ester thereof, the alkylphosphonic acid containing 6 to 22 carbon atoms. The particulate material is usually a pigment, extender or filler which is treated by mixing with the alkylphosphonic acid or ester for example in an aqueous dispersion or during a process step such as milling. The treated inorganic solid is particularly useful for preparing polymer compositions such as masterbatches.

Abstract: A synthetic alkali metal silicate pigment is modified with a source of a water soluble zirconium ion to form an oxy-hydroxy zirconium species precipitate on the pigment surface. The surface modified pigment is made by slurrying the pigment and reacting it with the source of a water soluble zirconium ion. The surface modified pigment provides improvements over conventional synthetic alkali metal silicate pigments in terms of optical properties, particularly in paper applications, and physical properties, particularly in rubber applications. The surface modified pigment is also useful as an extender or replacement for TiO.sub.2, a conventional synthetic alkali metal silicate such as a sodium-aluminosilicate pigment, a clay, a calcined clay or the like.