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)] | 35 Claims |
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.
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