Susceptors having disrupted regions for differential heating in a microwave oven

Claim 2

A packaging system for a single food product including susceptor heating means having selective responsiveness to microwave radiation, comprising: a susceptor for heating a single food product in response to microwave radiation, the susceptor being adapted to brown or crispen the surface of a food substance placed in close proximity thereto, the susceptor having an initially electrically continuous conductive film formed upon a support, the conductive film having a first electrically continuous region operative to heat responsive to microwave radiation and a second region, the second region having thin-line conductivity breaks formed in the conductive film which disrupt the electrical continuity of the conductive film to reduce heating of the second region in response to microwave radiation, the second region being formed by mechanically interrupting the electrical continuity of the conductive film in a predetermined pattern with the thin-line conductivity breaks without removing or chemically modifying the conductive film, the thin-line conductivity breaks being operative to adjust the selective responsiveness of the susceptor heating means when heating the single food product.

Claim 3

The packaging system according to claim 1, wherein: the second region of the conductive film comprises small discrete conductive film areas defined by the conductivity breaks int he conductive film, the small discrete conductive film areas having dimensions small enough to reduce the responsiveness of the second region to heating by microwave irradiation relative to said first region.

Claim 4

The packaging system according to claim 2, wherein: the conductive film is a metallized layer of aluminum having a resistivity between about 10 ohms per square and about 1700 ohms per square.

Claim 5

The packaging system according to claim 1, wherein: the second region of the conductive film comprises a plurality of substantially square shaped conductive film areas, the square shaped conductive film areas being separated from each other by breaks in the conductive film.

Claim 6

The packaging system according to claim 4, wherein: the square shaped conductive film areas in the second region have a length less than about 0.625 inches.

Claim 7

The packaging system according to claim 5, wherein: the conductive film is a metallized layer of aluminum having a resistivity between about 0.1 ohms per square and about 2000 ohms per square.

Claim 8

The packaging system according to claim 6, wherein: the metallized layer of aluminum has a resistivity greater than about 60 ohms per square.

Claim 9

The packaging system according to claim 4, wherein: the square shaped conductive film areas in the second region have a length less than about 0.3125 inches.

Claim 10

The packaging system according to claim 8, wherein: the conductive film is a metallized layer of aluminum having a resistivity between about 10 ohms per square and about 1700 ohms per square.

Claim 11

The packaging system according to claim 9, wherein: the metallized layer of aluminum has a resistivity between about 10 ohms per square and about 1700 ohms per square.

Claim 12

The packaging system according to claim 9, wherein: the metallized layer of aluminum has a resistivity between about 60 ohms per square and about 1650 ohms per square.

Claim 13

The packaging system according to claim 4, wherein: the square shaped conductive film areas in the second region have a length less than about 0.1563 inches.

Claim 14

The packaging system according to claim 12, wherein: the conductive film is a metallized layer of aluminum having a resistivity between about 10 ohms per square and about 1700 ohms per square.

Claim 15

The packaging system according to claim 4, wherein: the square shaped conductive film areas in the second region have a length less than about 0.0781 inches.

Claim 16

The packaging system according to claim 14, wherein: the conductive film is a metallized layer of aluminum having a resistivity between about 10 ohms per square and about 1700 ohms per square.

Claim 17

The packaging system according to claim 4, wherein: the conductive film is a metallized layer of aluminum having a resistivity between about 10 ohms per square and about 1700 ohms per square.

Claim 18

The packaging system according to claim 1, wherein: the conductive film is a metallized layer of aluminum.

Claim 19

The packaging system according to claim 17, wherein: the metallized layer of aluminum has a resistivity between about 10 ohms per square and about 1700 ohms per square.

Claim 20

The packaging system according to claim 17, wherein: the metallized layer of aluminum has a resistivity between about 60 ohms per square and about 1650 ohms per square.

Claim 21

A susceptor having variable responsiveness to heating from microwave radiation, wherein thin-line disruptions are made in a region of the susceptor to compensate for such variable responsiveness to provide for more uniform heating, comprising: (a) a support; (b) an initially electrically continuous metallized layer formed upon the support, the metallized layer being modified to form: (1) a first region that is operative to heat in response to microwave radiation; and, (2) a second region that would have a tendency to heat too much in response to microwave radiation, the second region having thin-line conductivity breaks formed in the initially electrically continuous metallized layer to disrupt the electrical continuity of the metallized layer prior to exposure to microwave radiation, the second region being formed by mechanically interrupting the electrical continuity of the conductive film in a predetermined pattern with thin-line conductivity breaks without removing or chemically modifying the conductive film, the thin-line conductivity breaks being operative to compensate for the second region's tendency to overheat; and, (c) the susceptor being adapted to heat the surface of a single food substance placed in close proximity thereto during exposure to microwave radiation.

Claim 22

A susceptor having variable responsiveness to heating from microwave radiation, wherein thin-line disruptions are made in a region of the susceptor to compensate for such variable responsiveness to provide for more uniform heating, comprising: (a) a support; (b) an initially electrically continuous metallized layer formed upon the support, the metallized layer being modified to form: (1) a first region that is operative to heat in response to microwave radiation; and, (2) a second region that would have a tendency to heat too much in response to microwave radiation, the second region having thin-line conductivity breaks formed in the initially electrically continuous metallized layer to disrupt the electrical continuity of the metallized layer prior to exposure to microwave radiation, the second region being formed by mechanically interrupting the electrical continuity of the conductive film in a predetermined pattern with thin-line conductivity breaks without removing or chemically modifying the conductive film, the thin-line conductivity breaks being operative to compensate for the second region's tendency to overheat; and, (c) the susceptor being adapted to heat the surface of a single food substance placed in close proximity thereto during exposure to microwave radiation.

Claim 23

The susceptor according to claim 20, wherein: the second region is less responsive to microwave radiation than the first region.

Claim 24

The susceptor according to claim 20, further comprising: (3) a third region of the metallized layer, the third region having conductivity breaks formed in the metallized layer prior to microwave radiation to reduce the third region's responsiveness to microwave radiation.

Claim 25

The susceptor according to claim 22, wherein: the third region is less responsive to microwave radiation than the second region.

Claim 26

The susceptor according to claim 22, wherein: the conductivity breaks in the metallized layer in the third region define a plurality of third subregions each having a surface area; the conductivity breaks in the metallized layer in the second region define a plurality of second subregions each having a surface area; and, the surface area of the individual third subregions being less than the surface area of the individual second subregions.

Claim 29

The method according to claim 25, wherein: said disrupting comprises cutting the thin metallized film of the susceptor in the first region.

Claim 30

The method according to claim 26, further comprising the step of: scoring the second region of the thin metallized film of the susceptor where the dimension of the continuous metallized film areas in the second region are larger than the dimensions of the continuous metallized film in the first region.

Claim 31

The method according to claim 25, wherein: said disrupting comprises separating the thin metallized film of the susceptor in the first region into a plurality of distinct subregions of continuous metallized film, where the individual subregions in the first region have a surface area less than the surface area of the second region.

Claim 34

A packaging system including susceptor heating means having selective responsiveness to microwave radiation, comprising: a susceptor for heating in response to microwave radiation, the susceptor being adapted to brown or crispen the surface of a single food substance placed in close proximity thereto, the susceptor having a susceptor surface that heats when exposed to microwave radiation, the susceptor having regions of different responsiveness to microwave radiation achieved by mechanically interrupting the electrical continuity of the susceptor surface in a predetermined pattern with thin-line conductivity breaks, without removing or chemically modifying the susceptor surface, to create disruptions in the susceptor surface, said disruptions affecting the heating response to a region to microwave radiation.

Claim 35

A packaging system including susceptor heating means having selective responsiveness to microwave radiation, comprising: a susceptor for heating in response to microwave radiation, the susceptor being adapted to brown or crispen the surface of a single food substance placed in close proximity thereto, the susceptor having a susceptor surface that heats when exposed to microwave radiation, the susceptor having regions of different responsiveness to microwave radiation achieved by mechanically interrupting the electrical continuity of the susceptor surface in a predetermined pattern with thin-line conductivity breaks, without removing or chemically modifying the susceptor surface, to create disruptions in the susceptor surface, said disruptions affecting the heating response to a region to microwave radiation.

Claim 36

The packaging system according to claim 30, wherein: a first region of the susceptor comprises small discrete areas defined by the disruptions in the susceptor surface, the small discrete areas having dimensions small enough to reduce the responsiveness of the first region to heating by microwave irradiation relative to said second region.

Claim 37

The packaging system according to claim 30, wherein: the first region of the susceptor comprises a plurality of substantially rectangular shaped susceptor surface areas defined by said disruptions in the susceptor surface.

Claim 40

A susceptor having a plurality of regions, where one region has reduced responsiveness to microwave heating, comprising: a first region of the susceptor surface which heats responsive to microwave radiation; and a second region of the susceptor surface, the second region having a disrupted susceptor surface, the second region being formed by mechanically interrupting the electrical continuity of the susceptor surface in a predetermined pattern with thin-line conductivity breaks, without removing or chemically modifying the susceptor surface, the second region having an additional significant capacitive component in the impedance of the susceptor, the second region being less responsive to the heating effects of microwave radiation.

Claim 41

A susceptor having a plurality of regions, where one region has reduced responsiveness to microwave heating, comprising: a first region of the susceptor surface which heats responsive to microwave radiation; and a second region of the susceptor surface, the second region having a disrupted susceptor surface, the second region being formed by mechanically interrupting the electrical continuity of the susceptor surface in a predetermined pattern with thin-line conductivity breaks, without removing or chemically modifying the susceptor surface, the second region having an additional significant capacitive component in the impedance of the susceptor, the second region being less responsive to the heating effects of microwave radiation.