PACKAGING MATERIALS FOR FOOD PRODUCTS
Provided herein are packaging materials that include a non-foamed layer and a foamed layer including a polyethylene.
1 . A packaging material comprising:
a non-foamed layer; and
a foamed layer comprising:
a polyethylene comprising about 20 wt. % to about 100 wt. % of the foamed layer; and
filler particles comprising about 0 wt. % to about 80% wt. % of the foamed layer,
wherein the foamed layer comprises foamed cells and the non-foamed layer and the foamed layer are a coextruded blown film.
2 . The packaging material of claim 1 , wherein the polyethylene is a low density polyethylene.
3 . The packaging material of claim 2 , wherein the low density polyethylene has a melt index of about 0.1 g/10 to about 2.0 g/10 min.
4 . The packaging material of claim 2 , wherein the low density polyethylene has a melt index of about 0.2 g/10 min to about 1.0 g/10 min.
5 . The packaging material of claim 2 , wherein the low density polyethylene comprises about 20 wt. % to about 100 wt. % of the foamed layer.
6 . The packaging material of claim 2 , wherein the low density polyethylene comprises about 70 wt. % to about 80 wt. % of the foamed layer.
7 . The packaging material of claim 1 , wherein the filler particles comprise about 10 wt. % to about 40 wt. % of the foamed layer.
8 . The packaging material of claim 1 , wherein the filler particles comprise at least one filler particle selected from the group consisting of a calcium carbonate, a sodium carbonate, a barium sulfate, a calcium sulfate, a sodium sulfate, a sodium phosphate, a potassium phosphate, and a calcium phosphate, and combinations thereof.
9 . The packaging material of claim 8 , wherein the filler particles comprise a calcium carbonate.
10 . The packaging material of claim 1 , wherein the foamed layer has a thickness of about 0.5 mil to about 10 mil.
11 . The packaging material of claim 1 , wherein the non-foamed layer comprises a high density polyethylene.
12 . The packaging material of claim 11 , wherein the high density polyethylene has a melt index of about 0.01 g/10 min to about 1 g/10 min.
13 . The packaging material of claim 11 , wherein the high density polyethylene has a melt index of about 0.40 to about 0.50.
14 . The packaging material of claim 11 , wherein the high density polyethylene comprises about 20 wt. % to about 60 wt. % of the non-foamed layer.
15 . The packaging material of claim 1 , wherein the non-foamed layer comprises filler particles.
16 . The packaging material of claim 15 , wherein the filler particles comprises a calcium carbonate.
17 . The packaging material of claim 16 , wherein the non-foamed layer comprises about 40 wt. % to about 80 wt. % of the calcium carbonate.
18 . The packaging material of claim 1 , wherein the packaging material comprises two non-foamed layers on opposite sides of the foamed layer.
19 . The packaging material of claim 1 , wherein the packaging material comprises two non-foamed layers on opposite sides of the foamed layer and two intermediate non-foamed layers on opposite sides of the foamed layer, wherein the first intermediate non-foamed layer is between the first non-foamed layer and the foamed layer and the second intermediate non-foamed layer is between the second non-foamed layer and the foamed layer.
20 . The packaging material of claim 1 , wherein the packaging material has a total thickness of about 5 mil to about 20 mil.
21 . A packaging material comprising:
an exterior foamed layer comprising high density polyethylene, calcium carbonate filler particles, and foamed cells formed from a chemical foaming agent,
an intermediate foamed layer comprising high density polyethylene, calcium carbonate filler particles, and foamed cells formed from a chemical foaming agent,
a foamed core layer comprising
about 60 wt. % to about 90 wt. % of a low density polyethylene;
about 10 wt. % to about 40 wt. % of a calcium carbonate; and
foamed cells,
an intermediate non-foamed layer comprising high density polyethylene and calcium carbonate filler particles; and
an non-foamed layer comprising high density polyethylene and calcium carbonate filler particles;
wherein the exterior foamed layer, intermediate foamed layer, foamed core layer, intermediate non-foamed layer, and non-foamed layer are a coextruded blown film.
22 . A packaging material comprising:
a non-foamed layer; and
a foamed layer comprising a high density polyethylene and filler particles as 40% to about 80% by weight of the foamed layer;
wherein the foamed layer has cavitated cells proximate filler particles and foamed cells resulting from the presence of a foaming agent;
wherein the non-foamed layer and the foamed layer are a coextruded blown film.
23 . The packaging material of claim 22 , wherein the non-foamed layer comprises a printable material.
24 . The packaging material of claim 22 , wherein the foamed layer is the innermost layer of the coextruded blown film.
25 . The packaging material of claim 22 , wherein the foamed layer contributes a surface roughness to a surface of the coextruded blown film upon which bacon or other meat is seated of about 1 to about 7 Sa μm using a 3D optical surface profiler.