Packaging material for food items containing permeating oils
A packaging material for oily or greasy food items includes one or more features for resisting penetration, masking penetration, or for a combination of resisting and masking penetration by the oily or greasy substance.
1 . An oil resistant packaging material comprising:
a substrate that is susceptible to discoloration by an oil; and
an oil resistant layer substantially overlying the substrate,
wherein the oil resistant layer comprises a polymer that is substantially resistant to penetration by oil.
2 . The packaging material of claim 1 , wherein the oil resistant layer comprises a single polymer.
3 . The packaging material of claim 1 , wherein the oil resistant layer comprises polypropylene.
4 . The packaging material of claim 5 , wherein the oil resistant layer has a basis weight of from about 1 to about 10 lbs/ream.
5 . The packaging material of claim 5 , wherein the oil resistant layer has a basis weight of from about 2 to about 6 lbs/ream.
6 . The packaging material of claim 1 , wherein the oil resistant layer comprises a blend of two or more polymers.
7 . The packaging material of claim 1 , wherein the oil resistant layer comprises:
from about 50 to 100 weight % polypropylene; and
up to about 50 weight % low density polyethylene, propylene-ethylene copolymer, polyethylene terephthalate, nylon 6,6, polyvinylidene chloride, polyvinyl alcohol, ethylene vinyl alcohol, or any combination thereof.
8 . The packaging material of claim 1 , wherein the oil resistant layer comprises a filler.
9 . The packaging material of claim 1 , wherein the oil resistant layer comprises from 0 to about 30 weight % filler.
10 . The packaging material of claim 1 , wherein
the substrate comprises paper or paperboard; and
the oil resistant layer comprises polypropylene and a filler selected from the group consisting of calcium carbonate, magnesium carbonate, silica, calcium oxide, alumina, titanium dioxide, and any combination thereof.
11 . The packaging material of claim 1 , further comprising a heat seal layer substantially overlying the oil resistant layer.
12 . The packaging material of claim 11 , wherein the heat seal layer comprises a thermoplastic polymer having a softening temperature of from about 180° F. to about 380° F.
13 . The packaging material of claim 11 , wherein
the substrate comprises paper or paperboard;
the oil resistant layer comprises polypropylene; and
the heat seal layer comprises metallocene polypropylene.
14 . A packaging material for a food item containing an oil, comprising:
a substrate that is susceptible to discoloration by an oil;
a tie layer substantially overlying the substrate;
an oil resistant layer substantially overlying the tie layer, the oil resistant layer comprising a polymer that is substantially resistant to penetration by oil; and
a heat seal layer substantially overlying the oil resistant layer.
15 . The packaging material of claim 14 , wherein
the substrate comprises paper or paperboard;
the tie layer comprises metallocene polypropylene;
the oil resistant layer comprises polypropylene; and
the heat seal layer comprises metallocene polypropylene.
16 . The packaging material of claim 14 , wherein
the paper or paperboard has a basis weight of from about 8 to about 250 lbs/ream;
the tie layer has a basis weight of from about 0.1 to about 5 lbs/ream;
the oil resistant layer has a basis weight of from about 0.1 to about 20 lbs/ream; and
the heat seal layer has a basis weight of from about 1 to about 15 lbs/ream.
17 . The packaging material of claim 14 , wherein the tie layer and the heat seal layer are formed from the same polymer.
18 . The packaging material of claim 14 , wherein the tie layer and the heat seal layer are formed from different polymers.
19 . A packaging material for masking staining by an oil, comprising:
a substrate that tends to absorb oils; and
at least one of an opacity modifying additive and a plurality of bleached fibers incorporated into the substrate.
20 . The packaging material of claim 19 , wherein the substrate includes an opacity modifying additive comprising a white pigment.
21 . The packaging material of claim 19 , wherein the substrate includes an opacity modifying additive comprising titanium dioxide.
22 . The packaging material of claim 19 , wherein the substrate is formed from a plurality of fibers, and at least 10 weight % of the fibers are bleached fibers.
23 . The packaging material of claim 19 , wherein
the substrate comprises paper having a basis weight of from about 30 to about 50 lbs/ream, including at least about 25 weight % bleached fiber, and
the opacity modifying additive comprises at least about 90 lbs of titanium dioxide per ton of paper.
24 . The packaging material of claim 19 , wherein
the substrate comprises paper having a basis weight of from about 30 to about 50 lbs/ream, including at least about 50 weight % bleached fiber, and
the opacity modifying additive comprises at least about 180 lbs of titanium dioxide per ton of paper.
25 . A packaging material for masking staining by an oil, comprising:
a substrate that tends to absorb oils; and
an opacity modifying layer substantially overlying the substrate, the opacity modifying layer comprising a polymer and an opacity modifying additive.
26 . The packaging material of claim 25 , wherein the opacity modifying additive comprises titanium dioxide.
27 . The packaging material of claim 25 , further comprising a tie layer positioned between the substrate and the opacity modifying layer.
28 . The packaging material of claim 25 , further comprising a heat seal layer substantially overlying the opacity modifying layer distal the substrate.
29 . A packaging material for masking staining by an oil, comprising:
a substrate that tends to absorb oils, thereby creating a stain; and
a stain masking layer overlying at least a portion of the substrate, the stain masking layer comprising a colorant, wherein the colorant closely resembles the color of the stain, obscures the glossiness of the stain, or any combination thereof.
30 . The packaging material of claim 29 , wherein the colorant comprises a dark, non-reflective pigment that closely resembles the color of the stain.
31 . The packaging material of claim 29 , wherein the colorant comprises a reflective pigment that obscures the glossiness of the stain.
32 . The packaging material of claim 29 , wherein the reflective pigment comprises aluminum flake, brass flake, a pearlescent pigment, or any combination thereof.
33 . The packaging material of claim 29 , wherein the colorant comprises a first, dark, non-reflective pigment that closely resembles the color of the stain, and a second, reflective pigment that obscures the glossiness of the stain.
34 . The packaging material of claim 29 , wherein the colorant comprises:
from about 50 to about 99 weight % carbon black; and
from about 1 to about 50 weight % aluminum flake.
35 . The packaging material of claim 29 , wherein the stain masking layer overlies at least a portion of the substrate in a substantially continuous configuration.
36 . The packaging material of claim 29 , wherein the stain masking layer overlies at least a portion of the substrate in a patterned configuration.
37 . The packaging material of claim 29 , wherein the colorant comprises carbon black and the stain masking layer overlies at least a portion of the substrate in a patterned configuration comprising lighter and darker shades of black.
38 . The packaging material of claim 29 , wherein an opacity modifying additive, a plurality of bleached fibers, or any combination thereof is incorporated into the substrate.
39 . The packaging material of claim 38 , wherein the opacity modifying additive comprises titanium dioxide.
40 . The packaging material of claim 29 , wherein
the stain masking layer overlies at least a portion of a first side of the substrate, and
the packaging material further comprises an opacity modifying layer overlying at least a portion of a second side of the substrate.
41 . The packaging material of claim 40 , wherein the opacity modifying layer comprises a polymer and an opacity modifying additive.
42 . The packaging material of claim 41 , wherein the opacity modifying additive comprises titanium dioxide.
43 . The packaging material of claim 41 , further comprising a tie layer positioned between the substrate and the opacity modifying layer.
44 . A packaging material for a food item containing an oil, comprising:
a paper-based substrate that appears to be stained when brought into contact with an oil;
a tie layer substantially overlying a first side of the substrate;
an oil resistant layer substantially overlying the tie layer, the oil resistant layer comprising
a polymer that is substantially resistant to penetration by oil, and
an opacity modifying additive;
a heat seal layer substantially overlying the oil resistant layer; and
a stain masking layer overlying at least a portion of a second side of the substrate, the stain masking layer comprising a colorant,
wherein the colorant
closely resembles the color of the stain,
obscures the glossiness of the stain, or
any combination thereof.
45 . The packaging material of claim 44 , wherein
the tie layer comprises low density polyethylene;
the polymer in the oil resistant layer comprises polypropylene;
the opacity modifying additive comprises titanium dioxide; and
the heat seal layer comprises low density polyethylene.
46 . The packaging material of claim 44 , wherein
the paper-based substrate has a basis weight of from about 8 to about 250 lbs/ream;
the tie layer has a basis weight of from about 0.1 to about 5 lbs/ream;
the oil resistant layer has a basis weight of from about 0.1 to about 20 lbs/ream; and
the heat seal layer has a basis weight of from about 1 to about 15 lbs/ream.
47 . The packaging material of claim 44 , wherein the colorant comprises:
a first, dark, non-reflective pigment that closely resembles the color of the stain; and
a second, reflective pigment that obscures the glossiness of the stain.
48 . The packaging material of claim 44 , wherein the colorant comprises:
from about 60 to about 80 weight % carbon black; and
from about 20 to about 40 weight % aluminum flake.
49 . A package formed from the packaging material of claim 44 .
50 . A package formed from the packaging material of claim 44 for containing potato-based food items.