Plasma Treated Susceptor Films
A microwave energy interactive structure comprises a polymer film having a pair of opposed sides, a first side of the pair of opposed sides being plasma treated, and a layer of microwave energy interactive material supported on the first side of the polymer film.
1 . A method of making a microwave energy interactive structure, comprising:
plasma treating a polymer film, the polymer film having a surface roughness, whereby plasma treating reduces the surface roughness of the polymer film; and
depositing a layer of microwave energy interactive material onto the plasma treated polymer film, the layer of microwave energy interactive material being operative for converting at least a portion of impinging microwave energy into thermal energy.
2 . The method of claim 1 , wherein plasma treating the polymer film comprises
at least partially ionizing a plasma treatment gas, and
exposing the polymer film to the at least partially ionized treatment gas at a plasma treatment energy.
3 . The method of claim 2 , wherein the plasma treatment gas is selected from the group consisting of argon, nitrogen, carbon dioxide, helium, oxygen, air, fluorine, and any combination thereof.
4 . The method of claim 2 , wherein the plasma treatment gas comprises argon.
5 . The method of claim 4 , wherein the plasma treatment energy is about 38 joules/square foot.
6 . The method of claim 2 , wherein the plasma treatment gas comprises nitrogen.
7 . The method of claim 6 , wherein the plasma treatment energy is about 25 joules/square foot.
8 . The method of claim 1 , wherein the surface roughness of the polymer film is at least partially attributable to the height of surface lamella, and plasma treating the polymer film reduces the height of surface lamella.
9 . The method of claim 1 , wherein plasma treating the polymer film reduces the surface roughness of the polymer film about 20% to about 50%.
10 . The method of claim 1 , wherein plasma treating the polymer film reduces the surface roughness of the polymer film about 25% to about 35%.
11 . The method of claim 1 , further comprising joining a support layer to the layer of microwave energy interactive material such that the layer of microwave energy interactive material is disposed between the polymer film and the support layer.
12 . The method of claim 11 , wherein the support layer comprises paper, paperboard, or any combination thereof.
13 . A microwave energy interactive structure comprising:
a polymer film having a pair of opposed sides, a first side of the pair of opposed sides being plasma treated; and
a layer of microwave energy interactive material supported on the first side of the polymer film, the layer of microwave energy interactive material being operative for converting at least a portion of impinging microwave energy into thermal energy.
14 . The microwave energy interactive structure of claim 13 , wherein the microwave energy interactive structure is operative for reaching a maximum temperature upon sufficient exposure to microwave energy, the maximum temperature of the microwave energy interactive structure being greater than a maximum temperature reached by a microwave energy interactive structure including a polymer film that is not plasma treated.
15 . The microwave energy interactive structure of claim 13 , wherein the layer of microwave energy interactive material has an optical density of from about 0.17 to about 0.28, the microwave energy interactive material comprising aluminum.
16 . The microwave energy interactive structure of claim 13 , wherein the polymer film comprises polyethylene terephthalate.
17 . The microwave energy interactive structure of claim 16 , wherein the polyethylene terephthalate is biaxially oriented.
18 . The microwave energy interactive structure of claim 13 , further comprising a support layer joined to the layer of microwave energy interactive material such that the layer of microwave energy interactive material is disposed between the polymer film and the support layer.
19 . The microwave energy interactive structure of claim 18 , wherein the support layer comprises paper, paperboard, or any combination thereof.
20 . The microwave energy interactive structure of claim 13 , comprising at least a portion of a microwave heating construct for heating, browning, and/or crisping a food item in a microwave oven.