Patterned microwave susceptor

• US 6,765,182 B2
• Filed: 04/09/2002
• Issued: 07/20/2004
• Est. Priority Date: 03/19/1998
• Status: Expired due to Term

• Current Assignee: Graphic Packaging International Incorporated
• Original Assignee: Graphic Packaging International Incorporated
• Inventors: Lafferty, Terrence P., Cole, Lorin R.
• Primary Examiner(s): Hoang, Tu Ba
• Application Number:
  US10/119,540
• Publication Number:
  US 20030000948A1
• Time in Patent Office: 833 Days
• Field of Search: 219/730-735, 219/728, 219/759, 426/107, 426/109, 426/234, 426/241, 426/243, 99D/IG.14
• US Class Current: 219/730
• CPC Class Codes: B65D 2581/3406 Pizza or bread
• CPC Class Codes: B65D 2581/344 Geometry or shape factors influencing the microwave heating properties
• CPC Class Codes: B65D 2581/3467 Microwave reactive layer shaped by delamination, demetallizing or embossing
• CPC Class Codes: B65D 2581/3472 Aluminium or compounds thereof
• CPC Class Codes: B65D 2581/3494 Microwave susceptor B65D2581/3487 takes precedence
• CPC Class Codes: B65D 81/3446 specially adapted to be heated by microwaves
• CPC Class Codes: H05B 6/6494 for cooking

Abstract

The heating effect of a microwave susceptor can be improved by providing a pattern of microwave transparent areas in the susceptor. The transparent areas are preferably circles having a diameter of about 0.5 inch. The distance between adjacent circles is preferably about 0.5 inch. The susceptor may be used to brown and crispen the crust of frozen pizza heated in a microwave oven. The crust of the pizza is browner, especially at its central area, than the crust of pizza heated using a conventional susceptor.

Claims

1. A microwave susceptor comprising:

a dimensionally stable substrate;

a plastic film supported by the dimensionally stable substrate; and

an electrically continuous metal layer deposited on the lastic film, the metal layer of a thickness that it absorbs microwave radiation and converts microwave energy into heat;

the metal layer defining a plurality of apertures within the metal layer only;

wherein

each of the plurality of apertures has a major linear dimension of about one-eighth an operating wavelength of a microwave oven; and

each of the plurality of apertures is spaced apart from the others.

3. The microwave susceptor of claim 1 or 2, wherein each of the plurality of apertures is formed as a closed geometrical figure selected from the group consisting of:

a polygon, a regular polygon, a circle, an ellipse, a square, a rectangle, a hexagon, a star, and a cross.

4. The microwave suscept or of claim 3, wherein the closed geometrical figure has an aspect ratio between 1 to 1 and 2 to 1.

5. The microwave susceptor of claim 1 or 2, wherein the apertures are distributed across the susceptor.

6. The microwave susceptor of claim 1 or 2 wherein the metal layer is adhered to the dimensionally stable substrate.

7. The microwave susceptor of claim 1 or 2, wherein the apertures are more concentrated toward a center region of the susceptor.

8. The microwave susceptor of claim 1 or 2, wherein the metal layer comprises aluminum.

12. The microwave susceptor of claim 1, wherein the closed geometrical figure has an aspect ratio between 1 to 1 and 2 to 1.

2. A microwave susceptor comprising:

a dimensionally stable substrate;

a plastic film supported by the dimensionally stable substrate; and

an electrically continuous metal layer deposited on the plastic film, the metal layer of a thickness that it absorbs microwave radiation and converts microwave energy into heat;

the metal layer defining a plurality of apertures within the metal layer only;

wherein

each of the plurality of apertures is spaced apart from the others; and

each of the plurality of apertures increases the heat generated by the metal layer in an area immediately adjacent to the perimeter of each of the plurality of apertures.

9. A microwave susceptor comprising:

a dimensionally stable substrate;

a plastic film supported by the dimensionally stable substrate; and

an electrically continuous metal layer deposited on the plastic film, the metal layer of a thickness that it absorbs microwave radiation and converts microwave energy into heat;

the metal layer defining a plurality of microwave inactive areas within the metal layer only;

wherein

each of the plurality of microwave inactive areas fins a major linear dimension of about one-eighth an operating wavelength of a microwave oven; and

each of the plurality of microwave inactive areas is spaced apart from the others.

10. A microwave susceptor comprising:

a dimensionally stable substrate;

a plastic film supported by the dimensionally stable substrate; and

an electrically continuous metal layer deposited on the plastic film, the metal layer of a thickness that it absorbs microwave radiation and converts microwave energy into heat;

the metal layer defining a plurality of microwave inactive areas within the metal layer only;

wherein

each of the plurality of microwave inactive areas is spaced apart from the others; and

each of the plurality of microwave inactive areas increases the heat generated by the metal layer in an area immediately adjacent to the perimeter of each of the plurality of microwave inactive areas.

11. The microwave susceptor of claim 9 or 10, wherein each of the plurality of microwave inactive areas is formed as a closed geometrical figure selected from the group consisting of:

a polygon, a regular polygon, a circle, an ellipse, a square, a rectangle, a hexagon, a star, and a cross.

13. The microwave susceptor of claim 9 or 10, wherein microwave inactive areas are distributed across the susceptor.

14. The microwave susceptor of claim 9 or 10, wherein the metal layer is adhered to the dimensionally stable substrate.

15. The microwave susceptor of claim 9 or 10, wherein the microwave inactive areas are more concentrated toward a center region of the susceptor.

16. The microwave susceptor of claim 9 or 10, wherein the metal layer comprises aluminum.