Microwave heater and method of manufacture
AssigneeThe Pillsbury Company
InventorsCharles H. Turpin, Michael R. Perry
Life of this patent
Estimating the term…
Abstract
A microwave food package with a heater and method of manufacture are provided. The heater includes a substrate coated with a microwave lossy material having a thickness in the range of between about 0.001 cm and about 0.025 cm and an inverse penetration depth greater than about 0.01 cm.sup.-1. The layer of lossy material is preferably in liquid form when applied to the substrate and is non-liquid when used. The lossy material can have electric field loss properties alone or magnetic loss properties and combination thereof.
Claims42
A microwave heater for use for heating or cooking food in a microwave oven, said heater comprising:
- (a) a thermally stable substrate having a first surface;
- and
- (b) a lossy layer on at least a portion of said substrate first surface, said loosy layer having at least one region thereof with thickness and inverse power penetration depth which have values within the ranges of about the values within Area A of FIG. 34.
A method of making a microwave heater for use for heating or cooking food in a microwave oven, said method comprising:
- (a) applying a mixture of microwave absorptive material and vehicle to a first surface of a thermally stable substrate;
- (b) curing said mixture to form a lossy layer which is solid;
- and
- (c) said lossy layer having at least one region thereof with thickness and inverse power penetration depth which have values within the ranges of about the values within Area A of FIG. 34.
A method of making a microwave heater for use for heating or cooking food in a microwave oven, said method comprising:
- (a) forming a liquid mixture of vehicle and microwave lossy material;
- (b) applying said liquid mixture to a surface of a thermally stable substrate to form a layer of said liquid mixture;
- and
- (c) curing said liquid mixture to thereby change the liquid into a solid lossy layer with said lossy layer having at least one region thereof with thickness and inverse power penetration depth which have values within the ranges of about the values within Area A of FIG. 34.
Dependencies are inferred from the claim text.