Patterned microwave susceptor element and microwave container incorporating same

Claim 2

A microwave heating surface comprising a plurality of non-overlapping closed curvilinear heating regions distributed generally throughout the heating surface, at least a first one of the closed curvilinear heating regions comprising a first plurality of discrete microwave absorptive features that are spaced-apart for enhancing microwave transmission and reducing microwave reflectance of the heating surface under load relative to a plain susceptor.

Claim 3

The microwave heating surface of claim 1 wherein the first plurality of microwave absorptive features comprises dissimilar microwave absorptive features distributed throughout the first heating region.

Claim 4

The microwave heating surface of claim 2 wherein the dissimilar microwave absorptive features are disposed in a repeating pattern throughout the first heating region.

Claim 5

The microwave heating surface of claim 1 wherein the first plurality of microwave absorptive features comprises similar microwave absorptive features distributed throughout the first heating region.

Claim 6

The microwave heating surface of claim 1 wherein each of the microwave absorptive features in the first plurality of microwave absorptive features is a patch comprising two essentially parallel opposing sides defined by respective boundaries of the first heating region.

Claim 7

The microwave heating surface of claim 1 wherein the first plurality of microwave absorptive features have a largest dimension no greater than one-quarter of the wavelength of the microwave energy.

Claim 8

The microwave heating surface of claim 1 wherein the first plurality of microwave absorptive features comprise thin metallic film patches formed on a polymeric substrate.

Claim 9

The microwave heating surface of claim 1 wherein at least a second one and a third one of the closed curvilinear heating regions comprise respective second and third pluralities of discrete microwave absorptive features that are spaced-apart for enhancing microwave transmission and reducing microwave reflectance of the heating surface under load relative to a plain susceptor.

Claim 10

The microwave heating surface of claim 8 wherein the first, second and third pluralities of microwave absorptive features have a largest dimension no greater than one-quarter of the wavelength of the microwave energy.

Claim 11

The microwave heating surface of claim 8 wherein the first, second and third pluralities of microwave absorptive features are thin metallic film patches formed on a polymeric substrate.

Claim 12

The microwave heating surface of claim 1 wherein the plurality of non-overlapping closed curvilinear heating regions are elliptical.

Claim 13

The microwave heating surface of claim 1 wherein the plurality of non-overlapping closed curvilinear heating regions are generally circular and concentric.

Claim 14

The microwave heating surface of claim 1 wherein: at least one of the closed curvilinear heating regions comprises a generally continuous microwave absorptive feature having a plurality of spaced-apart apertures therein; and at least one of the closed curvilinear heating regions comprises a generally continuous microwave absorptive feature.

Claim 15

A microwave heating surface comprising a plurality of discrete microwave absorptive features distributed generally throughout the microwave heating surface in a plurality of non-overlapping closed curvilinear heating regions and spaced-apart for enhancing microwave transmission and reducing microwave reflectance of the heating surface under load relative to a plain susceptor.

Claim 16

A microwave heating surface comprising a plurality of discrete microwave absorptive features distributed generally throughout the microwave heating surface in a plurality of non-overlapping closed curvilinear heating regions and spaced-apart for enhancing microwave transmission and reducing microwave reflectance of the heating surface under load relative to a plain susceptor.

Claim 17

A microwave susceptor structure comprising: a first layer of microwave transparent material; and a second layer of patterned microwave interactive material; wherein the patterned microwave interactive material comprises a plurality of arrangements of microwave interactive features, the arrangements comprising repeating patterns of some of the microwave interactive features disposed generally along respective close plane curves that are generally symmetrical about at least two orthogonal axes.

Claim 18

A microwave susceptor structure comprising: a first layer of microwave transparent material; and a second layer of patterned microwave interactive material; wherein the patterned microwave interactive material comprises a plurality of arrangements of microwave interactive features, the arrangements comprising repeating patterns of some of the microwave interactive features disposed generally along respective close plane curves that are generally symmetrical about at least two orthogonal axes.

Claim 19

The microwave susceptor structure of claim 15 wherein: the first layer comprises a polymeric sheet; and the microwave interactive material of the second layer comprises thin aluminum sputter-deposited on a first side of the polymeric sheet.

Claim 20

The microwave susceptor structure of claim 15 wherein the arrangements are disposed generally along respective non-overlapping ellipses symmetrical about respective major and minor axes, the major axis of the arrangements lying on one of the orthogonal axes and the minor axis of the arrangements lying on another of the orthogonal axes.

Claim 21

The microwave susceptor structure of claim 15 wherein the arrangements are disposed generally along respective concentric circles of different radius.

Claim 22

The microwave susceptor structure of claim 15 wherein the patterned microwave interactive material further comprises at least one arrangement of microwave transparent features, the arrangement of microwave transparent features comprising a repeating pattern of the microwave transparent features disposed generally along a close plane curve that is generally symmetrical about the at least two orthogonal axes.

Claim 23

The microwave susceptor structure of claim 15 wherein the patterned microwave interactive material further comprises a microwave interactive strip, the microwave interactive strip being disposed generally along a close plane curve that is generally symmetrical about the at least two orthogonal axes.

Claim 24

The microwave susceptor structure of claim 15 wherein the patterned microwave interactive material further comprises a close plane curve feature of microwave interactive material that is generally symmetrical about the at least two orthogonal axes.

Claim 25

The microwave susceptor structure of claim 15 wherein the patterned microwave interactive material further comprises: at least one arrangement of microwave transparent features, the arrangement of microwave transparent features comprising a repeating pattern of the microwave transparent features disposed generally along a close plane curve that is generally symmetrical about the at least two orthogonal axes; and a microwave interactive strip, the microwave interactive strip being disposed generally along a close plane curve that is generally symmetrical about the at least two orthogonal axes.

Claim 26

A microwave susceptor structure comprising: a first layer of microwave transparent material; and a second layer of patterned microwave interactive material comprising: a first arrangement of substantially identical first microwave interactive features along a circle of a first radius; a second arrangement of substantially identical second microwave interactive features along a circle of a second radius greater than the first radius, the second arrangement being concentric with the first arrangement; a third arrangement of substantially identical third microwave interactive features along a circle of a third radius greater than the second radius, the third arrangement being concentric with the second arrangement; and a fourth arrangement of substantially identical fourth microwave interactive features along a circle of a fourth radius greater than the third radius, the fourth arrangement being concentric with the third arrangement.

Claim 27

A microwave susceptor structure comprising: a first layer of microwave transparent material; and a second layer of patterned microwave interactive material comprising: a first arrangement of substantially identical first microwave interactive features along a circle of a first radius; a second arrangement of substantially identical second microwave interactive features along a circle of a second radius greater than the first radius, the second arrangement being concentric with the first arrangement; a third arrangement of substantially identical third microwave interactive features along a circle of a third radius greater than the second radius, the third arrangement being concentric with the second arrangement; and a fourth arrangement of substantially identical fourth microwave interactive features along a circle of a fourth radius greater than the third radius, the fourth arrangement being concentric with the third arrangement.

Claim 28

A microwave susceptor structure comprising: a first layer of microwave transparent material; and a second layer of patterned microwave interactive material comprising: a first arrangement of substantially identical first microwave interactive features along a circle of a first radius; a second arrangement of substantially identical second microwave interactive features along a circle of a second radius greater than the first radius, the second arrangement being concentric with the first arrangement; a third arrangement of substantially identical microwave transparent features along a circle of a third radius greater than the second radius, the third arrangement being concentric with the second arrangement; and a fourth arrangement of a microwave interactive strip along a circle of a fourth radius greater than the third radius, the fourth arrangement being concentric with the third arrangement.

Claim 29

A microwave susceptor structure comprising: a first layer of microwave transparent material; and a second layer of patterned microwave interactive material comprising: a first arrangement of substantially identical first microwave interactive features along a circle of a first radius; a second arrangement of substantially identical second microwave interactive features along a circle of a second radius greater than the first radius, the second arrangement being concentric with the first arrangement; a third arrangement of substantially identical microwave transparent features along a circle of a third radius greater than the second radius, the third arrangement being concentric with the second arrangement; and a fourth arrangement of a microwave interactive strip along a circle of a fourth radius greater than the third radius, the fourth arrangement being concentric with the third arrangement.

Claim 30

A microwave susceptor blank comprising: a first layer of microwave transparent material; a second layer of patterned microwave interactive material; and a third layer of microwave transparent material; wherein the second layer is disposed between the first and third layers; wherein the patterned microwave interactive material comprises a bottom heating region, a fold region bounding the bottom heating region, and a sidewall region bounding the fold region; and wherein the fold region comprises a plurality of curvilinear microwave transparent features disposed generally through out the fold region in a generally repeating pattern for relieving thermal stress in the fold region during heating of the susceptor.

Claim 31

A microwave susceptor blank comprising: a first layer of microwave transparent material; a second layer of patterned microwave interactive material; and a third layer of microwave transparent material; wherein the second layer is disposed between the first and third layers; wherein the patterned microwave interactive material comprises a bottom heating region, a fold region bounding the bottom heating region, and a sidewall region bounding the fold region; and wherein the fold region comprises a plurality of curvilinear microwave transparent features disposed generally through out the fold region in a generally repeating pattern for relieving thermal stress in the fold region during heating of the susceptor.

Claim 32

The microwave susceptor blank of claim 25 wherein the curvilinear microwave transparent features are disks of microwave transparent material.

Claim 33

A microwave susceptor blank comprising: a first layer of microwave transparent material; a second layer of patterned microwave absorptive material formed on the first layer and comprising a bottom heating region, a fold region bounding the bottom heating region, and a sidewall region bounding the fold region; and a third layer of microwave transparent supportive material, the first and third layers being laminated with the second layer disposed therebetween; wherein the bottom heating region comprises a plurality of non-overlapping closed curvilinear heating regions distributed generally throughout the bottom heating region, at least a first one of the closed curvilinear heating regions comprising a first plurality of discrete spaced-apart microwave absorptive features for enhancing microwave transmission and reducing microwave reflectance of the bottom heating region under load relative to a plain susceptor; wherein the fold region comprises a generally continuous microwave absorptive feature having a plurality of curvilinear microwave transparent features disposed therein in a generally repeating pattern for relieving thermal stress in the fold region upon exposure thereof to microwave energy; and wherein the sidewall region comprises a generally continuous microwave absorptive feature.

Claim 34

A microwave susceptor blank comprising: a first layer of microwave transparent material; a second layer of patterned microwave absorptive material formed on the first layer and comprising a bottom heating region, a fold region bounding the bottom heating region, and a sidewall region bounding the fold region; and a third layer of microwave transparent supportive material, the first and third layers being laminated with the second layer disposed therebetween; wherein the bottom heating region comprises a plurality of non-overlapping closed curvilinear heating regions distributed generally throughout the bottom heating region, at least a first one of the closed curvilinear heating regions comprising a first plurality of discrete spaced-apart microwave absorptive features for enhancing microwave transmission and reducing microwave reflectance of the bottom heating region under load relative to a plain susceptor; wherein the fold region comprises a generally continuous microwave absorptive feature having a plurality of curvilinear microwave transparent features disposed therein in a generally repeating pattern for relieving thermal stress in the fold region upon exposure thereof to microwave energy; and wherein the sidewall region comprises a generally continuous microwave absorptive feature.

Claim 35

The microwave susceptor blank of claim 27 further comprising a flange region disposed about the sidewall region, the flange region being generally devoid of microwave absorptive material.

Claim 36

The microwave susceptor blank of claim 27 wherein a second one and a third one of the closed curvilinear heating regions comprise respective second and third pluralities of discrete spaced-apart microwave absorptive features for enhancing microwave transmission and reducing microwave reflectance of the bottom heating region under load relative to a plain susceptor.

Claim 37

The microwave susceptor blank of claim 27 wherein: at least one of the closed curvilinear heating regions comprises a generally continuous microwave absorptive feature having a plurality of spaced-apart apertures therein; and at least one of the closed curvilinear heating regions comprises a generally continuous microwave absorptive feature.

Claim 38

A microwave container comprising: a bottom heating region comprising a plurality of non-overlapping closed curvilinear heating regions distributed generally throughout the bottom heating region and disposed on a microwave transparent supporting substrate, at least a first one of the closed curvilinear heating regions comprising a first plurality of discrete microwave absorptive features that are spaced-apart for enhancing microwave transmission and reducing microwave reflectance of the bottom heating region under load relative to a plain susceptor; a fold region disposed on the microwave transparent supporting substrate about the bottom region, the fold region comprising a generally continuous microwave absorptive feature having a plurality of curvilinear microwave transparent features disposed therein in a generally repeating pattern for relieving thermal stress in the fold region upon exposure to microwave energy; and a sidewall region disposed on the microwave transparent supporting substrate about the fold region, the sidewall region comprising a generally continuous microwave absorptive feature.

Claim 39

A microwave container comprising: a bottom heating region comprising a plurality of non-overlapping closed curvilinear heating regions distributed generally throughout the bottom heating region and disposed on a microwave transparent supporting substrate, at least a first one of the closed curvilinear heating regions comprising a first plurality of discrete microwave absorptive features that are spaced-apart for enhancing microwave transmission and reducing microwave reflectance of the bottom heating region under load relative to a plain susceptor; a fold region disposed on the microwave transparent supporting substrate about the bottom region, the fold region comprising a generally continuous microwave absorptive feature having a plurality of curvilinear microwave transparent features disposed therein in a generally repeating pattern for relieving thermal stress in the fold region upon exposure to microwave energy; and a sidewall region disposed on the microwave transparent supporting substrate about the fold region, the sidewall region comprising a generally continuous microwave absorptive feature.

Claim 40

The microwave container of claim 31 further comprising a flange region disposed on the microwave transparent supporting substrate about the sidewall region, the flange region being generally devoid of microwave absorptive material.

Claim 41

The microwave container of claim 31 wherein a second one and a third one of the closed curvilinear heating regions comprise respective second and third pluralities of discrete spaced-apart microwave absorptive features for enhancing microwave transmission and reducing microwave reflectance of the bottom heating region under load relative to a plain susceptor.

Claim 42

The microwave container of claim 31 wherein: at least one of the closed curvilinear heating regions comprises a generally continuous microwave absorptive feature having a plurality of spaced-apart apertures therein; and at least one of the closed curvilinear heating regions comprises a generally continuous microwave absorptive feature.

Claim 43

A microwave container comprising: a bottom region; a fold region disposed about the bottom region; and a sidewall region disposed about the fold region; the bottom region, the fold region, and the sidewall region being formed from a laminated material comprising: a first layer of microwave transparent material; a second layer of patterned microwave interactive material; and a third layer of microwave transparent material, the second layer being disposed between the first and third layers; the patterned microwave interactive material in the bottom region comprising a plurality of arrangements of microwave interactive features, the arrangements comprising repeating patterns of some of the microwave interactive features disposed generally along respective close plane curves that are generally symmetrical about at least two orthogonal axes; the patterned microwave interactive material in the fold region comprising a plurality of curvilinear microwave transparent features disposed generally through out the fold region in a generally repeating pattern for relieving thermal stress in the fold region during microwave heating; and the patterned microwave interactive material in the sidewall region comprising a microwave interactive strip disposed generally throughout the sidewall region.

Claim 44

A microwave container comprising: a bottom region; a fold region disposed about the bottom region; and a sidewall region disposed about the fold region; the bottom region, the fold region, and the sidewall region being formed from a laminated material comprising: a first layer of microwave transparent material; a second layer of patterned microwave interactive material; and a third layer of microwave transparent material, the second layer being disposed between the first and third layers; the patterned microwave interactive material in the bottom region comprising a plurality of arrangements of microwave interactive features, the arrangements comprising repeating patterns of some of the microwave interactive features disposed generally along respective close plane curves that are generally symmetrical about at least two orthogonal axes; the patterned microwave interactive material in the fold region comprising a plurality of curvilinear microwave transparent features disposed generally through out the fold region in a generally repeating pattern for relieving thermal stress in the fold region during microwave heating; and the patterned microwave interactive material in the sidewall region comprising a microwave interactive strip disposed generally throughout the sidewall region.

Claim 45

The microwave container of claim 35 , further comprising a flange region disposed about the sidewall region, the flange region being generally devoid of microwave interactive material.