Susceptors capable of balancing stress and effectiveness

Abstract

An outer portion of one or more layers of microwave interactive material, which is for becoming hot when exposed to microwave energy, is arranged in a manner that seeks to advantageously control heating, so that the outer portion of the microwave interactive material can safely be adjacent the periphery of a turntable tray. The turntable tray can be heated by the microwave interactive material so that a peak thermally induced stress occurs in the turntable tray at a position proximate the periphery of the tray. The layer(s) of microwave interactive material are configured in a manner so that the peak thermally induced stress is less than a predetermined amount.

1 . A construct for supporting food being cooked in a microwave oven, comprising:
 a support layer having an at least generally polygonal shape, the support layer including a length, a width, an edge, and a corner; and   a layer of microwave energy interactive material joined to the support layer, the layer of microwave energy interactive material being operative for becoming hot when exposed to microwave energy, the layer of microwave energy interactive material having a periphery including
 a first portion positioned closely adjacent to the edge of the support layer, and 
 a second portion spaced from the corner of the support layer so that at least a portion of the support layer is not covered by the layer of microwave energy interactive material, wherein the second portion of the periphery has a radius of curvature less than [((0.5)(the length of the support layer)) 2 +((0.5)(the width of the support layer)) 2 ] 0.5 . 
   
   
   
       2 . The construct of  claim 1 , wherein the radius of curvature is at least about one-half of the length of the support layer but less than [((0.5)(the length of the support layer)) 2 +((0.5)(the width of the support layer)) 2 ] 0.5 . 
   
   
       3 . The construct of  claim 1 , wherein the radius of curvature is at least about one-half of the width of the support layer but less than [((0.5)(the length of the support layer)) 2 +((0.5)(the width of the support layer)) 2 ] 0.5 . 
   
   
       4 . The construct of  claim 1 , wherein the radius of curvature is from about 70.9% to about 94.5% of [((0.5)(the length of the support layer)) 2 +((0.5)(the width of the support layer)) 2 ] 0.5 . 
   
   
       5 . The construct of  claim 1 , wherein the radius of curvature is from about 78.7% to about 88.2% of [((0.5)(the length of the support layer)) 2 +((0.5)(the width of the support layer)) 2 ] 0.5 . 
   
   
       6 . The construct of  claim 1 , wherein the radius of curvature is from about 82.7% to about 86.6% of [((0.5)(the length of the support layer)) 2 +((0.5)(the width of the support layer)) 2 ] 0.5 . 
   
   
       7 . The construct of  claim 1 , wherein the portion of the support layer not covered by the layer of microwave energy interactive material is substantially absent of microwave energy interactive material. 
   
   
       8 . The construct of  claim 1 , wherein
 the layer of microwave energy interactive material is joined to a first area of the support layer,   the portion of the support layer not covered by the layer of microwave energy interactive material defines a second area of the support layer, and   a patterned layer of microwave energy interactive material is joined to the second area of the support layer.   
   
   
       9 . The construct of  claim 8 , wherein the layer of microwave energy interactive material in the first area is substantially continuous. 
   
   
       10 . A construct for supporting food being cooked in a microwave oven, comprising:
 a support layer having a substantially rectangular shape, the support layer including a first pair of opposed edges having a length, a second pair of opposed edges having a length, and a plurality of corners joining each pair of adjacent edges; and   a layer of microwave energy interactive material mounted to the support layer, the layer of microwave energy interactive material being adapted to generate thermal energy when exposed to microwave energy, the layer of microwave energy interactive material having a periphery including
 a first pair of opposed edges positioned closely adjacent to the first pair of opposed edges of the support layer, 
 a second pair of opposed edges positioned closely adjacent to the second pair of opposed edges of the support layer, and 
 a plurality of corner portions spaced from the corners of the support layer so that at least a portion of the support layer adjacent to each corner is not covered by the layer of microwave energy interactive material, wherein the corner portions have a radius of curvature less than [((0.5)(the length of the first pair of opposed edges)) 2 +((0.5)(the length of the second pair of opposed edges)) 2 ] 0.5 . 
   
   
   
       11 . The construct of  claim 10 , wherein the radius of curvature is less than about 94.5% of [((0.5)(the length of the first pair of opposed edges)) 2 +((0.5)(the length of the second pair of opposed edges)) 2 ] 0.5 . 
   
   
       12 . The construct of  claim 10 , wherein the radius of curvature is at least about 70.9% of [((0.5)(the length of the first pair of opposed edges)) 2 +((0.5)(the length of the second pair of opposed edges)) 2 ] 0.5 . 
   
   
       13 . The construct of  claim 10 , wherein the radius of curvature is at least about one-half of the length of the first pair of opposed edges. 
   
   
       14 . The construct of  claim 10 , wherein the radius of curvature is at least about one-half of the length of the second pair of opposed edges. 
   
   
       15 . The construct of  claim 10 , wherein
 the layer of microwave energy interactive material is a substantially continuous layer of microwave energy interactive material, and   a patterned layer of microwave energy interactive material is mounted to the portion of the support layer not covered by the substantially continuous layer of microwave energy interactive material.   
   
   
       16 . A construct for supporting food being cooked in a microwave oven, comprising:
 a support layer including a plurality of edges including
 a first pair of edges having a linear dimension defining a length of the support layer, and 
 a second pair of edges having a linear dimension defining a width of the support layer; and 
   a layer of microwave energy interactive material overlying the support layer, the layer of microwave energy interactive material adapted to generate heat when exposed to microwave energy, the layer of microwave energy interactive material having a peripheral edge including
 a plurality of substantially linear portions having a length less than the respective linear dimension of the plurality of edges of the support layer, each linear portion being substantially collinear with a respective medial portion of the respective edge of the support layer, and 
 a plurality of substantially arcuate portions extending between adjacent pairs of linear portions, each arcuate portion having a radius of curvature less than [((0.5)(the length of the support layer)) 2 +((0.5)(the width of the support layer)) 2 ] 0.5 . 
   
   
   
       17 . The construct of  claim 16 , wherein the radius of curvature of each arcuate portion independently is
 at least about one-half of the linear dimension of the first pair of edges of the support layer,   at least about one-half of the linear dimension of the second pair of edges of the support layer, or   at least about one-half of the linear dimension of the first pair of edges of the support layer and at least about one-half of the linear dimension of the second pair of edges of the support layer.   
   
   
       18 . The construct of  claim 16 , wherein the layer of microwave energy interactive material is substantially continuous. 
   
   
       19 . The construct of  claim 16 , wherein
 the layer of microwave energy interactive material defines a first area of the support layer, and   a discontinuous layer of microwave energy interactive material overlies a second area of the support layer.   
   
   
       20 . The construct of  claim 16 , wherein the length of the support layer is approximately equal to the width of the support layer.