Food and beverage containers and methods of coating
View Patent ↗Food and beverage containers and methods of coating are provided. The food and beverage containers include a metal substrate that is at least partially coated with a coating prepared from a composition that includes a resin system, a crosslinker, and a catalyst. Preferably, the coating composition is substantially Bisphenol A-free.
1. A food or beverage container comprising a metal substrate, wherein at least a portion of the metal substrate is coated with a coating prepared from a composition comprising:
a resin system comprising carboxylic groups, hydroxyl groups, or combinations thereof;
a crosslinker comprising a phenolic crosslinker, an amino crosslinker, or a combination thereof; and
a catalyst comprising a titanium-containing catalyst, a zirconium-containing catalyst, or a combination thereof;
wherein the composition is substantially Bisphenol A-free.
2. The container of claim 1 , wherein the resin system includes a polyester resin and an acrylate resin.
3. The container of claim 1 , wherein the resin system further comprises oxirane groups.
4. The container of claim 1 , wherein the resin system is a water-soluble or water-dispersible system.
5. The container of claim 4 , wherein the resin system comprises a polyester resin, an acrylate resin, a grafted polyester-acrylate resin, or combinations thereof.
6. The container of claim 1 , wherein the crosslinker comprises a phenolic crosslinker.
7. The container of claim 6 , wherein the phenolic crosslinker has a weight average molecular weight of 800 to 8,000.
8. The container of claim 6 , wherein the phenolic crosslinker comprises a reaction product of components including phenol, cresol, p-phenylphenol, p-tert-butylphenol, p-tert-amylphenol, cyclopentylphenol, cresylic acid, or a combination thereof.
9. The container of claim 6 , wherein the phenolic crosslinker comprises a reaction product of components including phenol.
10. The container of claim 1 , wherein the crosslinker comprises an amino crosslinker.
11. The container of claim 10 , wherein the amino crosslinker is selected from benzoguanamine-formaldehyde resins, melamine-formaldehyde resins, esterified melamine-formaldehyde resins, glycoluril-formaldehyde resins, urea-formadehyde resins, or a combination thereof.
12. The container of claim 10 , wherein the amino crosslinker comprises a fully methylated hexamethoxymethyl melamine resin.
13. The container of claim 1 , wherein the catalyst comprises a titanium-containing catalyst.
14. The container of claim 13 , wherein the titanium-containing catalyst is selected from a titanium acetylacetonate, tetraalkyltitanates, isopropylorthotitanate, water soluble titanium chelated salts, triethanolamine chelates of titanium, tetratriethanolamine chelates of titanium, diammonium dihydroxybis[lactato(2)-O 1 O 2 ]titanate(2-), or a combination thereof.
15. The container of claim 13 , wherein the titanium-containing catalyst is diammonium dihydroxybis[lactato(2)-O 1 O 2 ]titanate(2-).
16. The container of claim 1 , wherein the catalyst comprises a zirconium-containing catalyst.
17. The container of claim 16 , wherein the zirconium-containing catalyst is selected from zirconium propionate, zirconium acetate, ammonium zirconyl carbonate, zirconate (2)-bis[carbonato(2)-O]dihydroxy-diammonium, zirconium chelated salts, sodium zirconium lactate, sodium zirconium glycolate, tetrakis [[2,2′,2″-nitrilotris(ethanolato)](1)-N,O]zirconium, or a combination thereof.
18. A method of coating a food or beverage container, the method comprising:
forming a composition comprising:
a resin system comprising carboxylic groups, hydroxyl groups, or combinations thereof;
a crosslinker comprising a phenolic crosslinker, an amino crosslinker, or a combination thereof; and
a catalyst comprising a titanium-containing catalyst, a zirconium-containing catalyst, or a combination thereof;
wherein the composition is substantially Bisphenol A-free; and
applying the composition to a metal substrate prior to or after forming the metal substrate into a food or beverage container or portion thereof.
19. The method of claim 18 , wherein applying the composition to a metal substrate comprises applying the composition to the metal substrate in the form of a planar coil or sheet, hardening the composition, and forming the substrate into a food or beverage container or portion thereof.
20. A food or beverage container comprising a metal substrate, wherein at least a portion of the metal substrate is coated with a coating prepared from a composition comprising:
a resin system comprising oxirane groups and optionally carboxylic groups, hydroxyl groups, or combinations thereof;
a crosslinker comprising a phenolic crosslinker, an amino crosslinker, or a combination thereof; and
a catalyst comprising a titanium-containing catalyst, a zirconium-containing catalyst, or a combination thereof.