Container coating system

• US 10,526,502 B2
• Filed: 03/15/2013
• Issued: 01/07/2020
• Est. Priority Date: 08/09/2012
• Status: Active Grant

• Current Assignee: Swimc, LLC (Sherwin-Williams Company)
• Original Assignee: Swimc, LLC (Sherwin-Williams Company)
• Inventors: Niederst, Jeffrey, Evans, Richard H., O'Brien, Robert M., Romagnoli, Kevin, Von Maier, Mark S., Tishey, Mary E., Paulson, Gregory M.
• Primary Examiner(s): Peng, Kuo Liang
• Application Number:
  US14/418,040
• Publication Number:
  US 20150197657A1
• Time in Patent Office: 2,489 Days
• CPC Class Codes: B05D 2202/00 Metallic substrate
• CPC Class Codes: B05D 7/227 of containers, cans or the like
• CPC Class Codes: B05D 7/544 the first layer is let to dry at least partially before applying the second layer
• CPC Class Codes: B65D 23/02 Linings or internal coatings
• CPC Class Codes: 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
• CPC Class Codes: B65D 85/70 for materials not otherwise provided for
• CPC Class Codes: C08G 2650/56 Polyhydroxyethers, e.g. phenoxy resins
• CPC Class Codes: C08G 59/063 with epihalohydrins
• CPC Class Codes: C08G 59/066 with chain extension or advancing agents
• CPC Class Codes: C08G 65/485 Polyphenylene oxides
• CPC Class Codes: C09D 127/06 Homopolymers or copolymers of vinyl chloride
• CPC Class Codes: C09D 163/00 Coating compositions based on epoxy resins; Coating compositions based on derivatives of epoxy resins
• CPC Class Codes: C09D 167/00 Coating compositions based on polyesters obtained by reactions forming a carboxylic ester link in the main chain based on polyester-amides C09D177/12; based on polyester-imides C09D179/08; Coating compositions based on derivatives of such polymers
• CPC Class Codes: C09D 171/00 Coating compositions based on polyethers obtained by reactions forming an ether link in the main chain based on polyacetals C09D159/00; based on epoxy resins C09D163/00; based on polythioether-ethers C09D181/02; based on polyethersulfones C09D181/06; Coating compositions based on derivatives of such polymers
• CPC Class Codes: C09D 171/12 Polyphenylene oxides
• CPC Class Codes: C09D 5/002 Priming paints C09D5/08 takes precedence
• CPC Class Codes: C09D 5/08 Anti-corrosive paints
• CPC Class Codes: Y10T 428/1379 Contains vapor or gas barrier, polymer derived from vinyl chloride or vinylidene chloride, or polymer containing a vinyl alcohol unit
• CPC Class Codes: Y10T 428/31786 Of polyester [e.g., alkyd, etc.]

Abstract

A multi-coat coating system having an undercoat composition and an overcoat composition, wherein the undercoat, overcoat or both the undercoat and overcoat contain a polymer having segments of a specified formula and are substantially free of polyhydric phenols having estrogenic activity greater than or equal to that of bisphenol S. The coating system is suitable for use on a food-contact surface of food or beverage containers.

Claims

1. A multi-coat coating system comprising an undercoat composition and an overcoat composition, wherein the undercoat comprises a polymer having at least two aryl or heteroaryl groups in which each aryl or heteroaryl group includes a ring, an oxygen atom attached to the ring and a substituent group attached to the ring at an ortho or meta position relative to the oxygen atom;

wherein the overcoat comprises;

at least one thermoplastic material;

or

a polyester polymer; and

wherein the coating system is substantially free of diphenols having estrogenic activity greater than or equal to that of bisphenol S,

wherein the undercoat polymer has one or more segments of the below Formula I;

2. A coating system according to claim 1, wherein one or more R¹ or R² groups are attached to at least one of the phenylene rings depicted in Formula I at an ortho position relative to the oxygen atom.

3. A coating system according to claim 1, wherein the polymer further includes two or more aryl or heteroaryl groups joined by a polar linking group or a linking group having a molecular weight of at least 125 Daltons.

4. A coating system according to claim 1, wherein each of the phenylene groups depicted in Formula I includes at least one R¹ group attached to the phenylene ring at an ortho position relative to the oxygen atom.

5. A coating system according to claim 1, wherein each of the phenylene groups depicted in Formula I includes an R¹ group attached to the phenylene ring at both ortho positions relative to the oxygen atom.

6. A coating system according to claim 1, wherein the R¹ groups independently comprise methyl or ethyl groups attached to the phenylene ring at an ortho position relative to the oxygen atom.

7. A coating system according to claim 1, wherein an R¹ group is attached to the phenylene ring at an ortho position relative to the oxygen atom, and a width measured perpendicular from a centerline of the phenylene ring to the maximal outside extent of the van der Waals volume of R¹ is greater than 4.5 Angstroms.

8. A coating system according to claim 1, wherein v is 1 to 4 and R² is —

CH₂—

.

9. A coating system according to claim 1,

wherein the segments of Formula I are derived from one or more of the diglycidyl ether of 4,4′

-methylenebis(2,6-di-t-butylphenol), the diglycidyl ether of 2,2′

-methylenebis(4-methyl-6-t-butylphenol), the diglycidyl ether of 4,4′

-methylenebis(2,6-dimethylphenol), the diglycidyl ether of 4,4′

-butylidenebis(2-t-butyl-5-methylphenol), the diglycidyl ether of bis-(3,5-dimethyl-4-hydroxyphenyl)-methane, or a derivative or combination thereof.

10. A coating system according to claim 1, wherein the overcoat comprises a thermoplastic material.

11. A coating system according to claim 10, wherein the thermoplastic material comprises polyvinyl chloride.

12. A coating system according to claim 10, wherein the thermoplastic material is dispersed in a liquid carrier.

13. A coating system according to claim 10, wherein the liquid carrier is non-aqueous.

14. A coating system according to claim 10, wherein the thermoplastic material comprises an organosol or plastisol.

15. A coating system according to claim 10, wherein the thermoplastic material comprises a vinyl organosol.

16. A coating system according to claim 1, wherein the polymer of the undercoat composition is a polyether polymer that contains a plurality of aromatic ether segments.

17. A coating system according to claim 16, wherein the polyether polymer is formed from reactants including a polyhydric phenol and a polyepoxide.

18. A coating system according to claim 1, wherein the polymer is derived from polyhydric phenols having a logarithmic Relative Proliferative Effect (RPE) of −

3 or less.

19. An article, comprising a container, or a portion thereof, comprising a metal substrate and a multi-coat coating system applied on at least a portion of the metal substrate comprising an undercoat composition and an overcoat composition, wherein the undercoat comprises a polymer having at least two aryl or heteroaryl groups in which each aryl or heteroaryl group includes a ring, an oxygen atom attached to the ring and a substituent group attached to the ring at an ortho or meta position relative to the oxygen atom;

wherein the overcoat comprises;

at least one thermoplastic material;

or

a polyester polymer; and

wherein the coating system is substantially free of diphenols having estrogenic activity greater than or equal to that of bisphenol S,

wherein the undercoat polymer has one or more segments of the below Formula I;

20. A method comprising:

applying an undercoat composition on at least a portion of a metal substrate prior to or after forming the metal substrate into a container,

drying or at least partially curing the undercoat composition, and

applying and curing an overcoat composition to produce a cured multi-coat coating adhered to the metal substrate,

wherein the undercoat comprises a polymer having at least two aryl or heteroaryl groups in which each aryl or heteroaryl group includes a ring, an oxygen atom attached to the ring and a substituent group attached to the ring at an ortho or meta position relative to the oxygen atom;

wherein the overcoat comprises;

at least one thermoplastic material;

or

a polyester polymer; and

wherein the coating system is substantially free of diphenols having estrogenic activity greater than or equal to that of bisphenol S,

wherein the undercoat polymer has one or more segments of the below Formula I;