# US 10,870,743 B2 · Coated pigments for coloring PVC > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,870,743 B2 - Document ID: US10870743B2 - Status: Granted - Kind: B2 - Application number: 14/648,464 - Filed: 2013-12-13 - Published: 2015-10-22 - Granted: 2020-12-22 - Earliest claimed: 2012-12-13 - Assignees: LANXESS Deutschland GmbH - Applicants: LANXESS Deutschland GmbH - Inventors: Krzysztof Chlopek; Ulrich Meisen; Ralf Gerhard Koenig - Web page: https://patentgrep.com/patent/US10870743B2 ## CPC - C08K 9/02: Ingredients treated with inorganic substances - C08K 5/07: Aldehydes; Ketones - C09C 1/22: Compounds of iron {(C09C1/0009, C09C1/0015, C09C1/0078 take precedence)} - C09C 1/24: Oxides of iron - C01P 2004/84: one phase coated with the other - C01P 2006/12: Surface area - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) - C09C: TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES (treatment of materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone C04B14/00, C04B18/00, C04B20/00); PREPARATION OF CARBON BLACK {; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS} - C01P: INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS ## Abstract Coated pigments for plastics, as well as processes for production of the pigments, the use thereof for colouring polyvinyl chloride (PVC), processes for colouring PVC, PVC coloured with such coated pigments, and also plastics products including such coated pigments, may include inorganic pigments coated with of at least one of hydroxides of magnesium, hydroxides of calcium, oxides of magnesium, and oxides of calcium. ## Claims ### Claim 1 A coated pigment comprising: inorganic pigment selected from the group consisting of iron oxides, iron oxide hydroxides, zinc ferrites, magnesium ferrites, manganese ferrites, and mixtures thereof; and at least one of hydroxides and oxides of at least one of magnesium and calcium bonded directly to the surface of the core of the inorganic pigment to form coated pigment; wherein, based on the total weight of the coated pigment, the coated pigment comprises: 3.5% to 30% by weight of magnesium and 0.001% to 0.1% by weight of calcium, or 5.5% to 30% by weight of calcium. ### Claim 2 (depends on 1) The coated pigment according to claim 1, wherein the coated pigment comprises: a core consisting of the inorganic pigment; and a coating surrounding at least a portion of the core and consisting of the hydroxides and/or oxides of magnesium and/or calcium. ### Claim 3 (depends on 1) The coated pigment according to claim 1, wherein the inorganic pigment is haematite, and the coated pigment has an isoelectric point of <7. ### Claim 4 (depends on 1) The coated pigment according claim 1, wherein the inorganic pigment is selected from the group consisting of iron oxides, iron oxide hydroxides, zinc ferrites, magnesium ferrites, manganese ferrites, and mixtures thereof, excluding haematite, and the coated pigment has an isoelectric point of 2 to 12. ### Claim 5 (depends on 1) The coated pigment according to claim 1, wherein the coated pigment comprises 3.5% to 25% by weight of magnesium or 5.5% to 25% by weight of calcium, based on the total weight of the coated pigment. ### Claim 6 (depends on 1) The coated pigment according to claim 1, wherein the coated pigment comprises 3.5% to 25% by weight of magnesium based on the total weight of the coated pigment. ### Claim 7 (depends on 1) The coated pigment according to claim 1, wherein: the at least one of hydroxides and oxides of at least one of magnesium and calcium comprises hydroxides of at least one of magnesium and calcium, and the at least one of magnesium and calcium comprise 5% to 25% by weight of the coated pigment; the inorganic pigment forms a core of the coated pigment, the hydroxides and oxides define a surrounding layer around the core, and a surface of the core of the inorganic pigment is bonded directly to the surrounding layer; and wherein, when the inorganic pigment is haematite, the coated pigment has an isoelectric point of <6.8; or when the inorganic pigment is iron oxides other than haemetite, iron oxide hydroxides, zinc ferrites, magnesium ferrites, manganese ferrites, or mixtures thereof, the coated pigment has an isoelectric point of 2 to 12. ### Claim 8 (depends on 1) The coated pigment according to claim 1, wherein the coated pigment comprises 5.5% to 25% by weight, of calcium, based on the total weight of the coated pigment. ### Claim 9 (depends on 1) A plastics product comprising at least one polymer and at least one coated pigment according to claim 1, wherein at least 50% by weight of the polymer is formed from monomer vinyl chloride. ### Claim 10 (depends on 9) The plastics product according to claim 9, wherein at least 80% by weight of the polymer is formed from the monomer vinyl chloride. ### Claim 11 (depends on 9) The plastics product according to claim 9, wherein the polymer is polyvinyl chloride. ### Claim 12 (depends on 11) The plastics product according to claim 11, wherein the polyvinyl chloride is pulverulent polyvinyl chloride. ### Claim 13 (depends on 11) The plastics product according to claim 11, wherein the polyvinyl chloride is rigid polyvinyl chloride. ### Claim 14 (depends on 9) The plastics product according to claim 9, comprising 10% to 90% by weight of the at least one coated pigment. ### Claim 15 (depends on 9) The plastics product according to claim 9, comprising 20% to 70% by weight of the at least one coated pigment. ### Claim 16 (depends on 9) The plastics product according to claim 9, comprising 0.1% to 10% by weight of the at least one coated pigment. ### Claim 17 (depends on 9) The plastics product according to claim 9, comprising 0.5% to 5% by weight of the at least one coated pigment. ### Claim 18 (depends on 9) The plastics product according to claim 9, comprising 0% to 15% by weight of plasticizer, based on the amount of vinyl chloride present in the plastics product. ### Claim 19 (depends on 9) The plastics product according to claim 9, comprising 0% to 12% by weight of plasticizer, based on the amount of vinyl chloride present in the plastics product. ### Claim 20 (depends on 1) A process for producing the coated pigment according to claim 1, the process comprising precipitating the coating onto the inorganic pigment by adding: at least one of magnesium salts and calcium salts; and a precipitant selected from the group of alkali metal hydroxides, alkaline earth metal hydroxides, and mixtures thereof, to an aqueous suspension of the at least one inorganic pigment. ### Claim 21 (depends on 20) The process for producing the coated pigment according to claim 20, wherein the process comprises one of: a) precipitating the coating onto the inorganic pigment by adding the at least one of magnesium salts and calcium salts to the aqueous suspension of the at least one inorganic pigment, followed by adding the precipitant, or b) precipitating the coating onto the inorganic pigment by adding the precipitant to the aqueous suspension of the at least one inorganic pigment, followed by adding the at least one of magnesium salts and calcium salts to the suspension. ### Claim 22 (depends on 20) The process for producing coated pigment according to claim 20, wherein the at least one of magnesium salts and calcium salts, and the precipitant are added in dissolved form. ### Claim 23 (depends on 20) The process for producing coated pigment according to claim 20, additionally comprising one, two, three or four of the steps of: i) isolating the coated pigment, ii) washing the coated pigment, iii) drying the coated pigment, and iv) comminuting the coated pigment. ### Claim 24 (depends on 20) The process for producing coated pigment according to claim 20, wherein the process does not include a calcination step. ### Claim 25 (depends on 11) A process for producing the plastics products according to claim 11, the process comprising at least one of kneading or extruding the polyvinyl chloride with the at least one coated pigment. ### Claim 26 (depends on 12) A process for producing the plastics product according to claim 12, the process comprising mixing the at least one coated pigment and the pulverulent polyvinyl chloride at a temperature just below the melting point of the polyvinyl chloride. ### Claim 27 (depends on 9) A product comprising at least one plastics product according to claim 9. ### Claim 28 (depends on 27) The product according to claim 27, wherein the product is one of window profiles, pipes, floor coverings, insulation material or roofing membranes.