# US 12,006,380 B2 · Multi-stage polymeric latexes, coating compositions containing such latexes, and articles coated therewith > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,006,380 B2 - Document ID: US12006380B2 - Status: Granted - Kind: B2 - Application number: 17/882,330 - Filed: 2022-08-05 - Published: 2023-02-09 - Granted: 2024-06-11 - Earliest claimed: 2017-09-01 - Assignees: Swimc LLC - Applicants: Swimc LLC - Inventors: Robert M. O'Brien; Mark Stuetelberg; Joseph D. Desousa; Mary Jo Scandolari; Nikolaus Koch; Stephen Pollin; Nusrah Hussain - Web page: https://patentgrep.com/patent/US12006380B2 ## CPC - C08F 2/001: {Multistage polymerisation processes characterised by a change in reactor conditions without deactivating the intermediate polymer (C08F295/00, C08F297/00 take precedence)} - B65D 25/14: Linings or internal coatings (of containers made by folding or erecting blanks made of paper B65D5/56 {; linings for domestic water storage heaters F24H1/183}) - B65D 65/42: Applications of coated or impregnated materials - C08F 220/06: Acrylic acid; Methacrylic acid; Metal salts or ammonium salts thereof - C08F 285/00: Macromolecular compounds obtained by polymerising monomers on to preformed graft polymers - C09D 4/06: {Organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond} in combination with a macromolecular compound other than an unsaturated polymer of groups C09D159/00 - C09D187/00 - C09D 5/024: {characterised by the additives} - C09D 7/40: Additives - C09D 133/02: Homopolymers or copolymers of acids; Metal or ammonium salts thereof - C09D 133/06: of esters containing only carbon, hydrogen and oxygen, the oxygen atom being present only as part of the carboxyl radical - C09D 133/12: Homopolymers or copolymers of methyl methacrylate - C09D 133/26: Homopolymers or copolymers of acrylamide or methacrylamide - C09D 151/003: {grafted on to macromolecular compounds obtained by reactions only involving unsaturated carbon-to-carbon bonds (C09D151/04, C09D151/06 take precedence)} - C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS - B65D: CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES - C09D: COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR (cosmetics A61K; processes for applying liquids or other fluent materials to surfaces, in general, B05D; staining wood B27K5/02; glazes or vitreous enamels C03C; natural resins, French polish, drying-oils, driers, turpentine, per se, C09F; polishing compositions other than French polish, ski waxes C09G; adhesives or use of materials as adhesives C09J; materials for sealing or packing joints or covers C09K3/10; materials for stopping leaks C09K3/12; processes for the electrolytic or electrophoretic production of coatings C25D) ## Abstract An aqueous coating composition useful in coating a variety of substrates, including interior or exterior portions of food or beverage cans. The coating composition includes a multi-stage polymeric latex having two or more emulsion polymerized stages in an aqueous carrier liquid, wherein the latex has one or both of: (i) a lower glass transition temperature (Tg) emulsion polymerized stage having a calculated Tg that is at least 20° C. lower than a calculated Tg of a higher Tg emulsion polymerized stage, or (ii) a gradient Tg with at least a 20° C. differential in the calculated Tg of monomers fed at the start of polymerization compared to monomers fed at the end of polymerization. When spray-applied on the interior of a food or beverage can, the composition exhibits a global extraction result of less than 50 ppm and a metal exposure value of less than 3 mA. ## Claims ### Claim 1 An aqueous interior spray beverage container coating composition comprising: an aqueous carrier liquid; and a multi-stage polymeric latex having two or more emulsion polymerized ethylenically unsaturated monomer stages, wherein: the latex has a lower Tg emulsion polymerized stage having a calculated Tg that is at least 20° C. lower than a calculated Tg of a higher Tg emulsion polymerized stage, and more than 50 weight percent of the emulsion polymerized stages have a calculated Tg of greater than 40° C. and the lower Tg emulsion polymerized stage has a calculated Tg of less than 40° C.; wherein the aqueous coating composition has a viscosity of from 20 to 80 seconds (Ford Cup #2, 25° C.); and wherein the coating composition, when spray applied onto an interior of a 355 mL no. 211 two-piece drawn and ironed aluminum beverage can at 115 milligrams per can coating weight and cured at 188° C. to 199° C. (measured at the can dome) for 55 seconds, has a dry film thickness less than about 0.53 mils and exhibits: (i) a global extraction result of less than 50 ppm, (ii) a metal exposure of less than 3 mA on average when the can is filled with 1% NaCl in deionized water and tested pursuant to the Initial Metal Exposure test method disclosed herein, and (iii) a metal exposure of less than 3.5 mA when tested pursuant to the Metal Exposure after Drop Damage test disclosed herein. ### Claim 2 (depends on 1) The coating composition of claim 1, wherein the latex has a lower Tg emulsion polymerized stage having a calculated Tg of less than 30° C. and a higher Tg emulsion polymerized stage having a calculated Tg of greater than 50° C. ### Claim 3 (depends on 1) The coating composition of claim 1, wherein the latex has a lower Tg emulsion polymerized stage having a calculated Tg of less than 20° C. and a higher Tg emulsion polymerized stage having a calculated Tg of greater than 60° C. ### Claim 4 (depends on 1) The coating composition of claim 1, wherein the latex has a lower Tg emulsion polymerized stage having a calculated Tg that is at least 40° C. lower than a calculated Tg of the higher Tg emulsion polymerized stage. ### Claim 5 (depends on 1) The coating composition of claim 1, wherein the latex has a lower Tg emulsion polymerized stage having a calculated Tg that is at least 60° C. lower than a calculated Tg of the higher Tg emulsion polymerized stage. ### Claim 6 (depends on 1) The coating composition of claim 1, wherein more than 50 weight percent of the emulsion polymerized stages have a calculated Tg of at least 60° C. ### Claim 7 (depends on 1) The coating composition of claim 1, wherein two or more of the emulsion polymerized stages are formed from monomers having in the aggregate a calculated Tg of at least 30° C. ### Claim 8 (depends on 1) The coating composition of claim 1, wherein the aqueous coating composition includes, based on total resin solids, at least 50 wt. % of the two or more emulsion polymerized stages. ### Claim 9 (depends on 1) The coating composition of claim 1, wherein the aqueous coating composition contains more than 70 wt. % resin solids from polymerized ethylenically unsaturated monomers based on total resin solids in the coating composition. ### Claim 10 (depends on 1) The coating composition of claim 1, wherein at least 50 wt. % of the monomers used to form one or more of the emulsion polymerized stages are (meth)acrylates. ### Claim 11 (depends on 1) The coating composition of claim 1, wherein at least 50 wt. % of the monomers used to form one or more of the emulsion polymerized stages are alkyl methacrylates. ### Claim 12 (depends on 1) The coating composition of claim 1, wherein at least one of the emulsion polymerized stages is formed from monomers including at least 80 wt. % of one or more of methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, and butyl methacrylate. ### Claim 13 (depends on 12) The coating composition of claim 12, wherein the coating composition is substantially free of styrene and substituted styrene compounds. ### Claim 14 (depends on 12) The coating composition of claim 12, wherein the coating composition does not contain any structural units derived from a bisphenol. ### Claim 15 (depends on 1) The coating composition of claim 1, wherein at least one of the emulsion polymerized stages is formed from monomers including a multi-ethylenically unsaturated monomer. ### Claim 16 (depends on 1) The coating composition of claim 1, wherein the coating composition is substantially free of each of bisphenol A, bisphenol F, and bisphenol S, the coating composition is not prepared using halogenated monomers, and the coating composition includes or is derived from no more than 0.5 wt. % of acrylamide-type monomers, if any, based on the aggregate weight of polymerizable monomers employed to make the latex. ### Claim 17 (depends on 1) The coating composition of claim 1, wherein the coating composition includes or is derived from no more than 5 wt. % polyether compounds or polymers based on the total coating composition solids. ### Claim 18 (depends on 1) The coating composition of claim 1, wherein one or more polymerizable surfactants are used in forming the multi-stage polymeric latex. ### Claim 19 (depends on 1) The coating composition of claim 1, wherein the aqueous coating composition further comprises a phenoplast crosslinker. ### Claim 20 (depends on 1) The coating composition of claim 1, wherein the coating composition, when spray applied onto an interior of a 355 mL no. 211 two-piece drawn and ironed aluminum beverage can at 115 milligrams per can coating weight and cured at 188° C. to 199° C. (measured at the can dome) for 55 seconds, exhibits a lower sidewall adhesion rating value of 9 or 10 after retort in 2% citric acid under pressure at 121° C. and tested according to ASTM D 3359—Test Method B. ### Claim 21 (depends on 1) The coating composition of claim 1, wherein the coating composition, when spray applied onto an interior of a 355 mL no. 211 two-piece drawn and ironed aluminum beverage can at 115 milligrams per can coating weight and cured at 188° C. to 199° C. (measured at the can dome) for 55 seconds, is capable of passing a necking and flanging test as indicated by a change of metal exposure after necking of less than 1.0 mA. ### Claim 22 (depends on 1) The coating composition of claim 1, wherein the lower Tg emulsion polymerized stage was emulsion polymerized before the higher Tg emulsion polymerized stage. ### Claim 23 (depends on 1) The coating composition of claim 1, wherein the weight ratio of the lower Tg emulsion polymerized stage relative to the higher Tg emulsion polymerized stage ranges from 25:75 to 48:52. ### Claim 24 (depends on 1) The coating composition of claim 1, wherein the aqueous carrier liquid contains greater than about 5% organic solvent based on the total weight of the aqueous carrier liquid. ### Claim 25 An aqueous interior spray beverage can coating composition comprising: an aqueous carrier liquid; and a multi-stage polymeric latex having two or more emulsion polymerized ethylenically unsaturated monomer stages, wherein: the latex has a lower Tg emulsion polymerized stage having a calculated Tg that is at least 20° C. lower than a calculated Tg of a higher Tg emulsion polymerized stage, and more than 50 weight percent of the emulsion polymerized stages have a calculated Tg of greater than 40° C. and the lower Tg emulsion polymerized stage has a calculated Tg of less than 40° C.; wherein the aqueous coating composition comprises a beta-hydroxyalkyl-amide crosslinker; has a viscosity of from 20 to 80 seconds (Ford Cup #2, 25° C.); and wherein the coating composition, when spray applied onto an interior of a 355 mL no. 211 two-piece drawn and ironed aluminum beverage can at 115 milligrams per can coating weight and cured at 188° C. to 199° C. (measured at the can dome) for 55 seconds, exhibits: (i) a global extraction result of less than 50 ppm, (ii) a metal exposure of less than 3 mA on average when the can is filled with 1% NaCl in deionized water and tested pursuant to the Initial Metal Exposure test method disclosed herein, and (iii) a metal exposure of less than 3.5 mA when tested pursuant to the Metal Exposure after Drop Damage test disclosed herein. ### Claim 26 (depends on 25) The coating composition of claim 25, wherein the coating composition does not contain formaldehyde or formaldehyde-containing compounds. ### Claim 27 An aqueous interior spray beverage can coating composition comprising: an aqueous carrier liquid; and a multi-stage polymeric latex having two or more emulsion polymerized ethylenically unsaturated monomer stages, wherein: the latex has a lower Tg emulsion polymerized stage having a calculated Tg that is at least 20° C. lower than a calculated Tg of a higher Tg emulsion polymerized stage, and more than 50 weight percent of the emulsion polymerized stages have a calculated Tg of greater than 40° C. and the lower Tg emulsion polymerized stage has a calculated Tg of less than 40° C.; wherein the aqueous coating composition has a total solids weight ranging from about 18% to about 22% and a viscosity of from 20 to 80 seconds (Ford Cup #2, 25° C.); and wherein the coating composition, when spray applied onto an interior of a 355 mL no. 211 two-piece drawn and ironed aluminum beverage can at 115 milligrams per can coating weight and cured at 188° C. to 199° C. (measured at the can dome) for 55 seconds, exhibits: (i) a global extraction result of less than 50 ppm, (ii) a metal exposure of less than 3 mA on average when the can is filled with 1% NaCl in deionized water and tested pursuant to the Initial Metal Exposure test method disclosed herein, and (iii) a metal exposure of less than 3.5 mA when tested pursuant to the Metal Exposure after Drop Damage test disclosed herein. ### Claim 28 An aqueous interior spray beverage can coating composition comprising: an aqueous carrier liquid that contains greater than about 5% organic solvent; and a multi-stage polymeric latex having two or more emulsion polymerized ethylenically unsaturated monomer stages, wherein: the latex has a lower Tg emulsion polymerized stage having a calculated Tg that is at least 20° C. lower than a calculated Tg of a higher Tg emulsion polymerized stage, and more than 50 weight percent of the emulsion polymerized stages have a calculated Tg of greater than 50° C. and the lower Tg emulsion polymerized stage has a calculated Tg of less than 40° C.; and wherein: the coating composition includes, based on total resin solids, at least 50 wt. % of the two or more emulsion polymerized stages; the coating composition has a total solids weight of 15 to 25%, based on the total weight of the coating composition; the coating composition is substantially free of styrene and is not prepared using halogenated monomers and is substantially free of each of bisphenol A, bisphenol F, and bisphenol S; and the coating composition, when spray applied onto an interior of a 355 mL no. 211 two-piece drawn and ironed aluminum beverage can at 115 milligrams per can coating weight and cured at 188° C. to 199° C. (measured at the can dome) for 55 seconds, exhibits: (i) a global extraction result of less than 50 ppm, (ii) a metal exposure of less than 3 mA on average when the can is filled with 1% NaCl in deionized water and tested pursuant to the Initial Metal Exposure test method disclosed herein, and (iii) a metal exposure of less than 3.5 mA when tested pursuant to the Metal Exposure after Drop Damage test disclosed herein. ### Claim 29 An aqueous interior spray beverage container coating composition comprising: an aqueous carrier liquid; and a multi-stage polymeric latex having two or more emulsion polymerized ethylenically unsaturated monomer stages, wherein: the latex has a lower Tg emulsion polymerized stage having a calculated Tg that is at least 20° C. lower than a calculated Tg of a higher Tg emulsion polymerized stage, and more than 50 weight percent of the emulsion polymerized stages have a calculated Tg of greater than 50° C. and the lower Tg emulsion polymerized stage has a calculated Tg of less than 40° C.; wherein the aqueous coating composition has a viscosity of from 20 to 80 seconds (Ford Cup #2, 25° C.); and wherein the coating composition, when spray applied onto an interior of a 355 mL no. 211 two-piece drawn and ironed aluminum beverage can at 115 milligrams per can coating weight and cured at 188° C. to 199° C. (measured at the can dome) for 55 seconds, exhibits: (i) a global extraction result of less than 50 ppm, (ii) a metal exposure of less than 3 mA on average when the can is filled with 1% NaCl in deionized water and tested pursuant to the Initial Metal Exposure test method disclosed herein, and (iii) a metal exposure of less than 3.5 mA when tested pursuant to the Metal Exposure after Drop Damage test disclosed herein. ### Claim 30 (depends on 29) The coating composition of claim 29, wherein the latex has a lower Tg emulsion polymerized stage having a calculated Tg of less than 30° C. ### Claim 31 (depends on 29) The coating composition of claim 29, wherein the latex has a lower Tg emulsion polymerized stage having a calculated Tg of less than 20° C. and a higher Tg emulsion polymerized stage having a calculated Tg of greater than 60° C. ### Claim 32 (depends on 29) The coating composition of claim 29, wherein the latex has a lower Tg emulsion polymerized stage having a calculated Tg that is at least 40° C. lower than a calculated Tg of the higher Tg emulsion polymerized stage. ### Claim 33 (depends on 29) The coating composition of claim 29, wherein the latex has a lower Tg emulsion polymerized stage having a calculated Tg that is at least 60° C. lower than a calculated Tg of the higher Tg emulsion polymerized stage. ### Claim 34 (depends on 29) The coating composition of claim 29, wherein more than 50 weight percent of the emulsion polymerized stages have a calculated Tg of at least 60° C. ### Claim 35 (depends on 29) The coating composition of claim 29, wherein two or more of the emulsion polymerized stages are formed from monomers having in the aggregate a calculated Tg of at least 30° C.