US6251451B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microwavable package
Assignee: Graphic Packaging International LLC
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Filing: 1997-08-26
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Granted: 2001-06-26
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Expires: 2017-08-26
Abstract
Abstract The disclosed invention provides a microwavable package for a food product. The package comprises a base with an active microwave energy heating element to support the food product. The active microwave heating element comprises energy collecting resonant loops, tuned structures, and transmission lines to collect incident microwave energy and redirect it to other parts of the food product. The microwave package also includes a cover comprising a microwave energy interactive layer including one or more apertures within the cover. The apertures promote localized fields to promote browning of the food product in the local areas around the apertures. The cover may also comprise a susceptor layer that is heated in localized areas around the apertures due to the fields promoted by the apertures and impingement by incident microwaves energy through the apertures, thereby providing localized browning of the food product.
Inventors
- 👤 Neilson Zeng
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:14
CPC Classifications
B; B65; B65D; B65D81/00; B65D81/34; B65D81/3446; B65D81/3453; B65D2581/00; B65D2581/34; B65D2581/3437; B65D2581/3439; B65D2581/344; B65D2581/3441; B65D2581/3452; B65D2581/3463; B65D2581/3464; B65D2581/3466; B65D2581/3486; B65D2581/3489; B65D2581/3494; Y; Y10; Y10S; Y10S99/00; Y10S99/14
Claims Analysis
Total Claims: 41
Claim 1
Independent Claim
93 words
A microwavable package comprising: a base to support a food product; an active microwave energy heating element on said base to effect heating of a food product upon impingement by microwave energy; and a cover spaced apart from said active microwave energy heating element to overlie said food product, said cover including a microwave energy interactive material layer extending substantially over said food product, said microwave energy interactive material including a plurality of apertures spaced about said cover, said apertures being sized to promote localized fields to promote browning of said food product.
Claim 2
Dependent Claim
93 words
A microwavable package comprising: a base to support a food product; an active microwave energy heating element on said base to effect heating of a food product upon impingement by microwave energy; and a cover spaced apart from said active microwave energy heating element to overlie said food product, said cover including a microwave energy interactive material layer extending substantially over said food product, said microwave energy interactive material including a plurality of apertures spaced about said cover, said apertures being sized to promote localized fields to promote browning of said food product.
Claim 3
Dependent Claim
18 words
A microwavable package as defined in claim 1 wherein said apertures are in the form of elongate slots.
Claim 4
Dependent Claim
17 words
A microwavable package as defined in claim 2 wherein said elongate slots are arranged in concentric rings.
Claim 5
Dependent Claim
13 words
A microwavable package as defined in claim 3 wherein said rings are circular.
Claim 6
Dependent Claim
17 words
A microwavable package as defined in claim 4 wherein the slots in said concentric rings are staggered.
Claim 7
Dependent Claim
27 words
A microwavable package as defined in claim 5 further including at least one layer of suscepting material on said cover and overlying said microwave energy interactive material.
Claim 8
Dependent Claim
20 words
A microwavable package as defined in claim 2 wherein microwave energy interactive material islands are located within said elongate slots.
Claim 9
Dependent Claim
17 words
A microwavable package as defined in claim 7 wherein said elongate slots are arranged in concentric rings.
Claim 10
Dependent Claim
13 words
A microwavable package as defined in claim 8 wherein said rings are circular.
Claim 11
Dependent Claim
17 words
A microwavable package as defined in claim 9 wherein the slots in said concentric rings are staggered.
Claim 12
Dependent Claim
22 words
A microwavable package as defined in claim 7 wherein each of said microwave energy interactive material islands has an aperture formed therein.
Claim 13
Dependent Claim
14 words
A microwavable package as defined in claim 11 wherein said apertures are substantially decussate.
Claim 14
Dependent Claim
78 words
A microwavable package as defined in claim 1 wherein said active microwave energy heating element includes a plurality of energy collecting structures, each of said energy collecting structures including resonant loops having a perimeter sufficient to limit currents induced therein to below a predetermined level upon impingement by incident microwave energy, said energy collecting structures distributing energy towards a central region of said food product to uniformly heat said food product and to inhibit charring of said base.
Claim 15
Dependent Claim
37 words
A microwave package as defined in claim 13 wherein said energy collecting structures include a pair of resonant loops interconnected by transmission lines, said transmission lines configured to provide a progressive power loss between said resonant loops.
Claim 16
Dependent Claim
47 words
A microwavable package as defined in claim 14 wherein the perimeter of said resonant loops and the length of each of said transmission lines are substantially equal to an integer multiple of the effective wavelength of said incident microwave energy projected onto said microwave energy heating element.
Claim 17
Dependent Claim
14 words
A microwavable package as defined in claim 15 wherein said resonant loops are circular.
Claim 18
Dependent Claim
28 words
A microwavable package as defined in claim 16 wherein said energy collecting structures are circumferentially spaced and arranged in a ring about the center of said active element.
Claim 19
Dependent Claim
31 words
A microwavable package as defined in claim 17 wherein said active microwave energy heating element further includes a plurality of tuned structures at spaced locations and positioned between adjacent resonant loops.
Claim 20
Dependent Claim
15 words
A microwavable package as defined in claim 18 wherein said tuned structures include nested loops.
Claim 21
Dependent Claim
16 words
A microwavable package as defined in claim 19 wherein said nested loops are joined by bridges.
Claim 22
Dependent Claim
35 words
A microwavable package as defined in claim 1 further including a plurality of spaced apertures provided through said base and active microwave energy heating element to allow moisture released from said food product to pass.
Claim 23
Dependent Claim
16 words
A microwavable package as defined in claim 21 wherein said apertures are arranged in concentric rings.
Claim 24
Dependent Claim
153 words
A microwavable package comprising: a base to support a food product; an active microwave energy heating element interposed between said food product and said base to effect heating of said food product upon impingement by microwave energy; a cover spaced apart from said active microwave energy heating element to overlie said food product, said cover comprising: microwave energy interactive material covering at least a portion of said food product, said microwave energy interactive material containing a plurality of apertures spaced about said cover; a substrate supporting and extending beyond the peripheral edge of said microwave energy interactive material to isolate electrically said base and said cover; and at least one layer of suscepting material interposed between said food product and said microwave energy interactive material; wherein said apertures are sized to promote a localized fields to locally enhance said at least one layer of suscepting material and promote browning of said food product.
Claim 25
Dependent Claim
153 words
A microwavable package comprising: a base to support a food product; an active microwave energy heating element interposed between said food product and said base to effect heating of said food product upon impingement by microwave energy; a cover spaced apart from said active microwave energy heating element to overlie said food product, said cover comprising: microwave energy interactive material covering at least a portion of said food product, said microwave energy interactive material containing a plurality of apertures spaced about said cover; a substrate supporting and extending beyond the peripheral edge of said microwave energy interactive material to isolate electrically said base and said cover; and at least one layer of suscepting material interposed between said food product and said microwave energy interactive material; wherein said apertures are sized to promote a localized fields to locally enhance said at least one layer of suscepting material and promote browning of said food product.
Claim 26
Dependent Claim
20 words
A microwavable package as defined in claim 23 wherein said microwave energy interactive material extends substantially over said food product.
Claim 27
Dependent Claim
18 words
A microwavable package as defined in claim 24 wherein said apertures are in the form of elongate slots.
Claim 28
Dependent Claim
26 words
A microwavable package as defined in claim 25 wherein said elongate slots are arranged in concentric circular rings, the slots in adjacent concentric rings being staggered.
Claim 29
Dependent Claim
20 words
A microwavable package as defined in claim 26 wherein microwave energy interactive material islands are located within said elongate slots.
Claim 30
Dependent Claim
26 words
A microwavable package as defined in claim 27 wherein said elongate slots are arranged in concentric circular rings, the slots in adjacent concentric rings being staggered.
Claim 31
Dependent Claim
22 words
A microwavable package as defined in claim 28 wherein each of said microwave energy interactive material islands has an aperture formed therein.
Claim 32
Dependent Claim
14 words
A microwavable package as defined in claim 29 wherein said apertures are generally decussate.
Claim 33
Dependent Claim
35 words
A microwavable package as defined in claim 23 wherein said base and active microwave energy heating element further include a plurality of spaced venting apertures to allow moisture released from said food product to pass.
Claim 34
Dependent Claim
17 words
A microwavable package as defined in claim 31 wherein said venting apertures are arranged in concentric rings.
Claim 35
Dependent Claim
39 words
A microwavable package as defined in claim 23 wherein said cover is flexible to overlie and conform to said food product, and further comprising a flexible wrap to constrain said base and cover and inhibit relative movement there between.
Claim 36
Dependent Claim
16 words
A microwavable package as defined in claim 33 wherein said base and cover are generally circular.
Claim 37
Dependent Claim
19 words
A microwavable package as defined in claim 33 wherein said food product is in the form of a pizza.
Claim 38
Dependent Claim
38 words
A microwavable package as defined in claim 1 further comprising: a tray comprising said base and including a plurality of spaced apertures in said tray to permit moisture released from a food product to pass through said tray.
Claim 39
Dependent Claim
16 words
A microwavable package as defined in claim 36 wherein said apertures are arranged in concentric rings.
Claim 40
Dependent Claim
20 words
A microwavable package as defined in claim 1 wherein the apertures are spaced about a peripheral margin of said cover.
Claim 41
Dependent Claim
20 words
A microwavable package as defined in claim 23 wherein the apertures are spaced about a peripheral margin of said cover.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2004-06-25 | 2004-12-25 | 2005-06-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-06-25 | 2008-12-25 | 2009-06-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-06-25 | 2012-12-25 | 2013-06-26 | $7700.00 | Window Closed / Lapsed |