| CPC C08F 2/001 (2013.01) [B65D 25/14 (2013.01); C09D 5/024 (2013.01); C09D 7/40 (2018.01); C09D 133/12 (2013.01); C09D 133/26 (2013.01)] | 27 Claims |
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1. An aqueous interior spray beverage container coating composition comprising 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 35° C. lower than a calculated Tg of a higher Tg emulsion polymerized stage, wherein the coating composition includes, based on total resin solids, at least 50 wt. % of the two or more emulsion polymerized stages;
wherein the coating composition includes from 15 wt. % to 25 wt % of solids, is substantially free of each of bisphenol A, bisphenol F, and bisphenol S, and 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;
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,
(iii) a metal exposure of less than 3.5 mA when tested pursuant to the Metal Exposure after Drop Damage test disclosed herein, and
(iv) a measured Tg of at least 50° C.
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23. An aqueous interior spray beverage container coating composition comprising 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 40° C. lower than a calculated Tg of a higher Tg emulsion polymerized stage, wherein the coating composition includes, based on total resin solids, at least 70 wt. % of the two or more emulsion polymerized stages;
wherein the coating composition:
includes from 15 wt. % to 25 wt % of solids,
has a viscosity of from 20 to 80 seconds (Ford Cup #2, 25° C.),
is substantially free of each of bisphenol A, bisphenol F, and bisphenol S,
is not prepared using halogenated monomers, and
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;
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,
(iii) a metal exposure of less than 3.5 mA when tested pursuant to the Metal Exposure after Drop Damage test disclosed herein, and
(iv) a measured Tg of at least 70° C.
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