Black food containers
View Patent ↗A black pigmented disposable food container is preferably made from a polypropylene matrix polymer, optionally including polyethylene and further includes a mineral filler and a black colorant composition consisting essentially of a black iron oxide pigment and a green pigment.
1. A thermoformed disposable food container formed from a thermoplastic sheet material comprising polypropylene, wherein the sheet is pigmented black with a colorant composition consisting essentially of a black iron oxide pigment and phthalocyanine green, the weight ratio of black iron oxide pigment to phthalocyanine green being at least about 10:1 and said black iron oxide pigment is present in an amount of up to about 5 weight percent of the container, and wherein further the sheet material exhibits a lower extractables content in heptane compared to a like sheet material pigmented black with carbon black.
2. The thermoformed disposable food container according to claim 1 , wherein said black iron oxide pigment is present in an amount of less than 4 weight percent of said container.
3. The thermoformed disposable food container according to claim 1 , wherein said polypropylene is melt-blended with said colorant composition.
4. The thermoformed disposable food container according to claim 1 , wherein said thermoplastic sheet material further comprises a polymer selected from the group consisting of polyesters, polystyrenes, polyethylenes, polyamides, polyacrylates, polysulfones, polyetherketones, polycarbonates, acrylics, polyphenylene sulfides, acetals, polyetherimides, polyphenylene ethers or oxides, styrene-maleic anhydride copolymers, styrene-acrylonitrile copolymers, polyvinylchlorides and mixtures thereof.
5. The thermoformed disposable food container according to claim 4 , wherein said thermoplastic sheet material is a mineral-filled thermoplastic sheet material.
6. The thermoformed disposable food container according to claim 5 , wherein said mineral-filled thermoplastic sheet material includes mica.
7. The thermoformed disposable food container according to claim 1 , wherein said thermoplastic sheet material contains less than about 0.25 weight percent titanium dioxide.
8. The thermoformed disposable food container according to claim 7 , wherein said mineral-filled thermoplastic sheet material contains no titanium dioxide.
9. The thermoformed disposable food container according to claim 8 , wherein said black iron oxide pigment is present in an amount of less than 3 percent by weight of said container.
10. The thermoformed disposable food container according to claim 1 , having a wall caliper of from about 10 to about 50 mils.
11. The thermoformed disposable food container according to claim 10 , having a wall caliper of from about 15 to about 25 mils.
12. A thermoformed disposable food container made from a black-pigmented, mineral-filled polypropylene sheet comprising from about 30 to about 80 percent by weight of a matrix polymer composition comprising a polypropylene polymer and optionally including a polyethylene polymer, from about 10 to about 60 weight percent of a mineral filler, wherein said container is pigmented with a black colorant composition consisting essentially of a black iron oxide pigment and phthalocyanine green, the weight ratio of black iron oxide pigment to phthalocyanine green is at least about 10:1, and said black iron oxide pigment is present in an amount up to about of 5 weight percent of said container, and wherein further the sheet material exhibits a lower extractables content in heptane compared to a like sheet material pigmented black with carbon black.
13. The thermoformed disposable food container according to claim 12 , containing less than 4 weight percent black iron oxide pigment.
14. The thermoformed disposable food container according to claim 12 , wherein said matrix polymer composition is melt-blended with said colorant composition.
15. The thermoformed disposable food container according to claim 12 , containing less than about 0.25 weight percent titanium dioxide.
16. The thermoformed disposable food container according to claim 15 , containing no titanium dioxide.
17. The thermoformed disposable food container according to claim 16 , wherein said composition contains from about 1 weight percent to about 3 weight percent of a black iron oxide pigment.
18. The thermoformed disposable food container according to claim 16 , containing less than about 3 weight percent of a black iron oxide pigment.
19. The thermoformed disposable food container according to claim 16 , containing about 2 weight percent of a black iron oxide pigment.
20. The thermoformed disposable food container according to claim 12 , wherein said matrix polymer composition consists of a polypropylene polymer and a polyethylene polymer.
21. The thermoformed disposable food container according to claim 20 , wherein said polyethylene polymer is present in an amount of from about 1 to about 15 percent by weight of said container.
22. The thermoformed disposable food container according to claim 21 , wherein said polyethylene polymer composition is present in an amount of from 2.5 to about 7.5 percent by weight of said container.
23. The thermoformed disposable food container according to claim 22 , wherein said polyethylene polymer is HDPE.
24. The thermoformed disposable food container according to claim 12 , wherein said polypropylene polymer is present in an amount of from about 40 to about 60 percent by weight of said container.
25. The thermoformed disposable food container according to claim 24 , wherein said polypropylene polymer is isotactic polypropylene.
26. The thermoformed disposable food container according in claim 12 , having a wall caliper of from about 10 to about 50 mils.
27. The thermoformed disposable food container according to claim 26 , having a wall caliper of from about 15 to about 25 mils.
28. A thermoformed disposable food container made from a black-pigmented, mineral-filled polypropylene sheet comprising from about 30 to about 80 percent by weight of a matrix polymer composition comprising a polypropylene polymer and optionally including a polyethylene polymer, from about 20 to about 40 weight percent of a mineral filler, wherein said container is pigmented with a black colorant composition consisting essentially iron black iron oxide pigment and a phthalocyanine green pigment, wherein said black iron oxide pigment is present in an amount of up to about 5 weight percent of said container, and wherein the thermoformed disposable food container further comprises from about 2.5 to about 25 weight percent calcium carbonate and from about 20 to about 40 weight percent mica.