Moisture resistant coating
Some embodiments of the invention generally relate to a moisture barrier coating that is biodegradable and compostable. Some embodiments also relate to a coating that is dual ovenable. Such coatings may be used to increase moisture resistance and provide non-stick or release characteristics when applied to biodegradable and compostable disposable food packaging and food service items. In some embodiments, a plasticizer, an amide wax and optionally a rosin are added to a cellulose-ester-based coating to increase moisture resistance. In other embodiments, a biodegradable polymer, an amide wax, optionally a plasticizer, and optionally a rosin are added to a cellulose-ester-based coating to drastically increase moisture resistance. In still other embodiments, phospholipids or medium-chain triglycerides or increased levels of amide wax may be added to the either of the embodiments above to provide enhanced release characteristics.
1. A coating composition comprising:
a cellulose ester;
a wax comprising oleamide or N,N′-ethylene-bis-oleamide;
a plasticizer; and
a solvent.
2. The composition of claim 1 wherein the cellulose ester comprises cellulose acetate propionate, cellulose acetate butyrate, cellulose acetate, or nitrocellulose.
3. The composition of claim 1 wherein the plasticizer comprises a citric acid ester, triacetin or tributyrin.
4. The composition of claim 1 wherein the solvent comprises methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ethanol, propanol, acetone, water, hydrocarbons.
5. The composition of claim 1 , further comprising a rosin, wherein the rosin comprises dimerized rosin or glycerol esters of partially dimerized rosin.
6. A coating composition comprising:
a cellulose ester;
a wax comprising oleamide or N,N′-ethylene-bis-oleamide;
a biodegradable polymer; and
a solvent.
7. The composition of claim 6 wherein the cellulose ester comprises cellulose acetate propionate, cellulose acetate butyrate, cellulose acetate or nitrocellulose.
8. The composition of claim 6 wherein the biodegradable polymer comprises a polyvinyl acetate polymer, polylactic acid polymer, or polyvinyl butyral copolymer.
9. The composition of claim 6 wherein the biodegradable polymer comprises poly(vinyl acetate-ethylene) copolymer and the cellulose ester component comprises cellulose acetate propionate.
10. The composition of claim 9 wherein the solvent comprises methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ethanol, propanol, acetone, water, hydrocarbons.
11. The composition of claim 6 wherein the solvent comprises methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ethanol, propanol, acetone, water, hydrocarbons.
12. The composition of claim 6 , further comprising a plasticizer, wherein the plasticizer comprises a citric acid ester, triacetin or tributyrin.
13. The composition of claim 6 , further comprising a rosin, wherein the rosin comprises dimerized rosin or glycerol esters of partially dimerized rosin.
14. A coating composition comprising:
a cellulose ester, wherein the cellulose ester comprises cellulose acetate propionate;
an amide wax, wherein the amide wax comprises oleamide or N,N′-ethylene-bis-oleamide;
a biodegradable polymer, wherein the biodegradable polymer comprises a polyvinyl acetate polymer, polylactic acid polymer, or polyvinyl butyral polymer; and
a solvent, wherein the solvent comprises methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ethanol, propanol, acetone, water, hydrocarbons.
15. The composition of claim 14 wherein the biodegradable polymer comprises an aqueous lattice of poly(vinyl acetate) polymer or poly(vinyl acetate-ethylene).
16. The composition of claim 14 wherein the biodegradable polymer comprises a polylactic acid polymer.
17. A method of manufacturing the composition of claim 14 comprising mixing the components of the composition that is not the biodegradable polymer, and then adding the biodegradable polymer.
18. A method of manufacturing the composition of claim 14 comprising mixing the components of the composition together, wherein the composition is not heated above the melting point of the amide wax.
19. A coating composition comprising:
a cellulose ester;
a biodegradable polymer;
a release agent;
a solvent; and
a wax comprising oleamide or N,N′-ethylene-bis-oleamide.
20. The composition of claim 19 wherein the cellulose ester comprises cellulose acetate propionate, cellulose acetate butyrate, cellulose acetate or nitrocellulose.
21. The composition of claim 19 wherein the biodegradable polymer comprises a polyvinyl acetate polymer, polylactic acid polymer, or polyvinyl butyral copolymer.
22. The composition of claim 19 wherein the biodegradable polymer comprises poly(vinyl acetate-ethylene) copolymer and the cellulose ester component comprises cellulose acetate propionate.
23. The composition of claim 19 wherein the release agent comprises a phospholipid or a medium chain triglyceride.
24. An article comprising:
a coating; and
a substrate selected from the group consisting of starch, cellulose, cellulose derivative and PLA,
wherein the coating comprises:
a cellulose ester;
a wax comprising oleamide or N,N′-ethylene-bis-oleamide;
a plasticizer; and
a solvent.
25. The article of claim 24 wherein the cellulose ester comprises cellulose acetate propionate, cellulose acetate butyrate, cellulose acetate, or nitrocellulose.
26. The article of claim 24 wherein the plasticizer comprises a citric acid ester, triacetin or tributyrin.
27. The article of claim 24 wherein the solvent comprises methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ethanol, propanol, acetone, water, hydrocarbons.
28. The article of claim 24 wherein the coating further comprises a rosin, and wherein the rosin comprises dimerized rosin or glycerol esters of partially dimerized rosin.