Latex coating composition having reduced flavor scalping properties

Patent metadata

Field	Value
Publication number	US-2020385602-A1
Application number	US-201716318033-A
Country	US
Kind code	A1
Filing date	Jul 13, 2017
Priority date	Jul 15, 2016
Publication date	Dec 10, 2020
Grant date	—

Abstract

A coating composition for a food or beverage can includes an emulsified latex polymer formed by polymerizing an ethylenically unsaturated monomer component in the presence of an aqueous dispersion of a water-dispersible emulsifying polymer.

First claim

1 . An article comprising:
one or more of a body portion or an end portion of a food or beverage can comprising a metal substrate; and a coating composition disposed thereon, wherein the coating composition includes an emulsified latex polymer comprising a reaction product of ingredients including an ethylenically unsaturated monomer component polymerized in the presence of an aqueous dispersion of an emulsifying polymer having a number average molecular weight (Mn) of at least about 8,500, and a cured film of the coating composition has a glass transition temperature (Tg) of at least about 40° C. wherein the coating composition is substantially free of each of bisphenol A, bisphenol F, and bisphenol S, including epoxides thereof.

2 . (canceled)

3 . (canceled)

4 . The article of claim 1 , wherein the coating composition comprises a cured coating composition.

5 . The article of claim 1 , wherein the ethylenically unsaturated monomer component comprises a mixture of monomers that includes at least one oxirane functional group-containing alpha, beta-ethylenically unsaturated monomer in an amount of 0.1 wt. % to 30 wt. %, based on a total weight of the mixture of monomers.

6 . (canceled)

7 . The article of claim 1 , wherein the emulsifying polymer:
a) is a polymer salt that includes anionic salt groups, cationic salt groups, or a combination thereof; or b) comprises an acrylic polymer, a polyurethane polymer, a polyester resin, an alkyd resin, a polyolefin, or a combination thereof; or c) comprises an acid- or anhydride-functional acrylic polymer, or a salt thereof, or d) comprises a salt of an acid- or anhydride-functional polymer and an amine.

8 . (canceled)

9 . (canceled)

10 . (canceled)

11 . (canceled)

12 . (canceled)

13 . (canceled)

14 . (canceled)

15 . The article of claim 1 , wherein the ethylenically unsaturated component comprises about 40 to about 80 wt. % and the emulsifying polymer comprises about 20 to about 60 wt. % of the emulsified latex polymer, based on the total weight of the ethylenically unsaturated monomer component and the emulsifying polymer, and wherein the emulsifying polymer has a number average molecular weight of 8,500 to 50,000 and a an acid number of about 40 to about 400 milligrams (mg) KOH per gram of emulsifying polymer.

16 . (canceled)

17 . (canceled)

18 . (canceled)

19 . The article of claim 1 , wherein the coating composition is substantially free of any structural units derived from a bisphenol.

20 . (canceled)

21 . The article of claim 1 , wherein the coating composition exhibits less than about 50% aldehyde loss when evaluated for flavor scalping.

22 . (canceled)

23 . (canceled)

24 . (canceled)

25 . (canceled)

26 . (canceled)

27 . (canceled)

28 . The article of claim 1 , wherein the food or beverage can contains a food or beverage product.

29 . The article of claim 1 , wherein the coating composition:
a. is suitable for forming a cured continuous inside spray coating on an interior surface of a two-piece drawn and ironed aluminum beverage can when sprayed on such surface at a coating weight of 0.16 to 3.1 mg/cm 2 (1 to 20 mg/in 2 ); b. includes 10 to 40% by weight of the emulsified latex polymer; c. has a viscosity from 20 to 50 seconds using Ford Viscosity Cup #2 at 25° C.; d. the ethylenically unsaturated component comprises 40 to 80 wt. % of the emulsified latex polymer and the emulsifying polymer comprises 20 to 60 wt. % of the emulsified latex polymer, based on the total weight of the ethylenically unsaturated monomer component and the emulsifying polymer; e. the emulsifying polymer has an acid number of 40 to 400 milligrams (mg) KOH per gram of emulsifying polymer; and f. when spray applied inside a 355 ml aluminum beverage can at a 100 to 130 mg/can coating weight, provides a metal exposure value less than 3.5 mA after a drop damage test.

30 . A method, comprising:
providing a coating composition that includes an emulsified latex polymer comprising a reaction product of ingredients including an ethylenically unsaturated monomer component polymerized in the presence of an aqueous dispersion of an emulsifying polymer having a number average molecular weight (Mn) of at least about 8,500, and a cured film of the coating composition has a glass transition temperature (Tg) of at least about 40° C. and is substantially free of each of bisphenol A, bisphenol F, and bisphenol S, including epoxides thereof; and applying the coating composition to a metal substrate prior to or after forming the metal substrate into a food or beverage can or portion thereof.

31 . The method of claim 30 , wherein the coating composition comprises a cured coating composition.

32 . The method of claim 30 , wherein the ethylenically unsaturated monomer component comprises a mixture of monomers that includes at least one oxirane functional group-containing alpha, beta-ethylenically unsaturated monomer in an amount of 0.1 wt. % to 30 wt. %, based on the weight of the monomer mixture.

33 . The method of claim 30 , wherein the emulsifying polymer:
a. is a polymer salt that includes anionic salt groups, cationic salt groups, or a combination thereof; or b. comprises an acrylic polymer, a polyurethane polymer, a polyester resin, an alkyd resin, a polyolefin, or a combination thereof; or c. comprises an acid- or anhydride-functional acrylic polymer, or a salt thereof, or d. comprises a salt of an acid- or anhydride-functional polymer and an amine.

34 . The method of claim 30 , wherein the ethylenically unsaturated component comprises 40 to 80 wt. % and the emulsifying polymer comprises 20 to 60 wt. % of the emulsified latex polymer, based on the total weight of the ethylenically unsaturated monomer component and the emulsifying polymer, and wherein the emulsifying polymer has a number average molecular weight of 8,500 to 50,000 and an acid number of 40 to 400 milligrams (mg) KOH per gram of emulsifying polymer.

35 . The method of claim 30 , wherein the coating composition is substantially free of any structural units derived from a bisphenol.

36 . The method of claim 30 , wherein the coating composition exhibits less than 50% aldehyde loss when evaluated for flavor scalping.

37 . The method of claim 30 , wherein the coating composition:
a. is suitable for forming a cured continuous inside spray coating on an interior surface of a two-piece drawn and ironed aluminum beverage can when sprayed on such surface at a coating weight of 0.16 to 3.1 mg/cm 2 (1 to 20 mg/in 2 ); b. includes 10 to 40% by weight of the emulsified latex polymer; c. has a viscosity from 20 to 50 seconds using Ford Viscosity Cup #2 at 25° C.; d. the ethylenically unsaturated component comprises 40 to 80 wt. % of the emulsified latex polymer and the emulsifying polymer comprises 20 to 60 wt. % of the emulsified latex polymer, based on the total weight of the ethylenically unsaturated monomer component and the emulsifying polymer; e. the emulsifying polymer has an acid number of 40 to 400 milligrams (mg) KOH per gram of emulsifying polymer; and f. when spray applied inside a 355 ml aluminum beverage can at a 100 to 130 mg/can coati

Assignees

• Swimc Llc

Inventors

• O'Brien Robert M
• Stuetelberg Mark
• Riazzi Arthur
• Scandolari Mary Jo
• Huynh Nhan T
• Koch Nikolaus J
• Puaud Samuel
• Riddle David M

Classifications

• C09D5/002

  Priming paints (C09D5/08 takes precedence) · CPC title

• C09D7/20

  Diluents or solvents · CPC title

• C09D125/04

  Homopolymers or copolymers of styrene · CPC title

• B05D2202/25

  based on Al · CPC title

• C09D133/00

  Coating compositions based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Coating compositions based on derivatives of such polymers · CPC title