Granted Patent B2

US 9,061,798 · App. 14/264,378 · Granted Jun 23, 2015

Abstract

Claims (32)

1. An article, comprising:

a food or beverage can, or a portion thereof, comprising:

a metal substrate; and

a cured coating disposed on at least a portion of the metal substrate, the cured coating formed from a coating composition comprising:

an aqueous dispersion of a polyurethane-urea polymer, and

a vinyl polymer.

2. The article of claim 1 , wherein the polyurethane-urea polymer includes salt groups.

3. The article of claim 1 , wherein the polyurethane-urea polymer has a number average molecular weight greater than 5,000, and wherein the polyurethane-urea polymer is formed using at least 1% by weight of an isocyanate compound.

4. The article of claim 1 , wherein polyurethane-urea polymer is present in an amount of at least 5 wt-%, based on the total weight of the vinyl polymer and polyurethane-urea polymer, and wherein the vinyl polymer is present in an amount of at least 15 weight percent, based on the total weight of the polymer and polyurethane-urea polymer.

5. The article of claim 1 , wherein the polyurethane-urea polymer includes at least about 5 urea linkages.

6. The article of claim 1 , wherein the polyurethane-urea polymer includes one or more unsaturated polycyclic groups.

7. The article of claim 1 , wherein the coating composition, when present on an aluminum beverage can end at a dry film thickness of 7 milligrams per square inch, passes less than 5 milliamps of current after being exposed for 4 seconds to a room-temperature electrolyte solution containing 1% by weight of NaCl dissolved in water.

8. The article of claim 1 , wherein the polyurethane-urea polymer is the reaction product of:

a polyurethane prepolymer having a number average molecular weight of from 2,000 to 6,000 and at least one isocyanate group, and

a polyamine.

9. The article of claim 8 , wherein the polyurethane polymer includes one or more aliphatic carbon-carbon double bonds.

10. The article of claim 9 , wherein the one or more aliphatic double bonds are present in one or more groups formed from functionalized butadiene or polybutadiene.

11. The article of claim 1 , wherein the vinyl polymer has a number average molecular weight of at least 100,000.

12. The article of claim 11 , wherein at least 40 weight percent of the vinyl polymer comprises an alkyl acrylate, alkyl methacrylate, or a combination thereof, based on the total non-volatile weight of ingredients used to make the vinyl polymer, and wherein the coating composition is substantially free of bound bisphenol A and aromatic glycidyl ether compunds.

13. An article, comprising:

a food or beverage can, or a portion thereof, comprising:

a metal substrate; and

a cured coating disposed on at least a portion of the metal substrate, the cured coating formed from a coating composition comprising:

an aqueous dispersion of a polyurethane polymer having one or more aliphatic carbon-carbon double bonds, and

a vinyl polymer.

14. The article of claim 13 , wherein the one or more aliphatic double bonds are present in one or more groups formed from functionalized butadiene or polybutadiene.

15. The article of claim 14 , wherein a latex polymer includes both the polyurethane polymer and the vinyl polymer.

16. The article of claim 13 , wherein the polyurethane polymer and the vinyl polymer are linked to one another by one or more covalent linkages.

17. The article of claim 16 , wherein a latex polymer includes both the polyurethane polymer and the vinyl polymer.

18. The article of claim 16 , wherein the one or more covalent linkages comprises a carbonate ester, epoxy, ether, imide, imine, or urea linkage.

19. The article of claim 16 , wherein the one or more covalent linkages are hydrolytically stable covalent linkages.

20. The article of claim 16 , wherein the coating composition is present on a food-contact surface of the metal substrate.

Assignments (8)