US4962000A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microwave absorbing composite
Assignee: 3M Co
•
Filing: 1989-05-05
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Granted: 1990-10-09
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Expires: 2009-05-05
Abstract
Abstract Microwave absorbing composite comprising at least two zones of material capable of absorbing microwave energy, each set of said two zones being separated by one zone of material transparent to or transmissive of microwave energy. The microwave energy absorbing zones are selected such that the composite is incapable of arcing in a microwave oven whereof the maximum power output does not exceed 2000 watts at a frequency of 2.45 GHz. The composite of this invention can be used for such purposes as crisping, browning, or otherwise heating food products, as a material for packaging, or as a package venting material.
Inventors
- 👤 Jeffrey O. Emslander
- 👤 Curtis L. Larson
- 👤 Pierre H. LePere
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 05:21
CPC Classifications
B; B65; B65D; B65D81/00; B65D81/34; B65D81/3446; B32; B32B; B32B27/00; B32B27/36; B65D2581/00; B65D2581/34; B65D2581/3437; B65D2581/3439; B65D2581/3452; B65D2581/3463; B65D2581/3466; B65D2581/3471; B65D2581/3472; B65D2581/3474; B65D2581/3477; B65D2581/3478; B65D2581/3479; B65D2581/3486; B65D2581/3487; Y; Y10; Y10T; Y10T428/00; Y10T428/13; Y10T428/1303; Y10T428/1352; Y10T428/249921; Y10T428/249953; Y10T428/31504; Y10T428/31678; Y10T428/31692
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
145 words
A microwave absorbing composite comprising at least two zones of material capable of absorbing microwave energy, said microwave energy absorbing zones consisting of one or more layers of electrically conductive material, each pair of said microwave energy absorbing zones being separated by a zone of material transparent to microwave energy, said microwave transparent zone consisting of one or more layers of electrically insulative material, and at least one layer of adhesive capable of bonding said composite to a substrate, said adhesive having sufficient mechanical strength to overcome any distortion forces so that said composite does not curl or slip relative to the substrate to which it is adhered as the composite heats in response to microwave energy, provided that said composite is incapable of arcing in a microwave oven whereof the maximum power output does not exceed 2000 watts of a frequency of 2.45 HHz.
Claim 2
Dependent Claim
145 words
A microwave absorbing composite comprising at least two zones of material capable of absorbing microwave energy, said microwave energy absorbing zones consisting of one or more layers of electrically conductive material, each pair of said microwave energy absorbing zones being separated by a zone of material transparent to microwave energy, said microwave transparent zone consisting of one or more layers of electrically insulative material, and at least one layer of adhesive capable of bonding said composite to a substrate, said adhesive having sufficient mechanical strength to overcome any distortion forces so that said composite does not curl or slip relative to the substrate to which it is adhered as the composite heats in response to microwave energy, provided that said composite is incapable of arcing in a microwave oven whereof the maximum power output does not exceed 2000 watts of a frequency of 2.45 HHz.
Claim 3
Dependent Claim
12 words
The composite of claim 1 wherein said adhesive is a pressure-sensitive adhesive.
Claim 4
Dependent Claim
12 words
The composite of claim 1 wherein said adhesive is a silicone-based adhesive.
Claim 5
Dependent Claim
12 words
The composite of claim 1 wherein said adhesive is an acrylic-based adhesive.
Claim 6
Dependent Claim
13 words
The composite of claim 1 wherein said electrically conductive material comprises a metal.
Claim 7
Dependent Claim
13 words
The composite of claim 5 wherein said metal is a vacuum deposited metal.
Claim 8
Dependent Claim
14 words
The composite of claim 1 wherein said electrically conductive material comprises a metal oxide.
Claim 9
Dependent Claim
20 words
The composite of claim 1 wherein said electrically conductive material comprises a dispersion of electrically conductive materials in a binder.
Claim 10
Dependent Claim
13 words
The composite of claim 1 wherein said electrically insulative material comprises a polymer.
Claim 11
Dependent Claim
17 words
The composite of claim 9 wherein said polymer is in the form of an extruded polymeric film.
Claim 12
Dependent Claim
16 words
The composite of claim 1 wherein said zone of material transparent to microwave energy comprises paper.
Claim 13
Dependent Claim
19 words
The composite of claim 1 wherein there are up to ten zones of material capable of absorbing microwave energy.
Claim 14
Dependent Claim
10 words
A package having applied thereto the composite of claim 1.
Claim 15
Dependent Claim
17 words
The package of claim 13 wherein said composite is applied over a thermoplastic portion of said package.
Claim 16
Dependent Claim
17 words
The package of claim 13 wherein said composite is applied over a perforated portion of said package.
Claim 17
Dependent Claim
93 words
A microwave absorbing composite consisting of at least two zones of material capable of absorbing microwave energy, said microwave energy absorbing zones consisting of one or more layers of electrically conductive material, each pair of said microwave energy absorbing zones being separated by a zone of material transparent to microwave energy, said microwave transparent zone consisting of one or more layers of electrically insulative material, provided that said composite is incapable of arcing in a microwave oven whereof the maximum power output does not exceed 2000 watts at a frequency of 2.45 GHz.
Claim 18
Dependent Claim
93 words
A microwave absorbing composite consisting of at least two zones of material capable of absorbing microwave energy, said microwave energy absorbing zones consisting of one or more layers of electrically conductive material, each pair of said microwave energy absorbing zones being separated by a zone of material transparent to microwave energy, said microwave transparent zone consisting of one or more layers of electrically insulative material, provided that said composite is incapable of arcing in a microwave oven whereof the maximum power output does not exceed 2000 watts at a frequency of 2.45 GHz.
Claim 19
Dependent Claim
13 words
The composite of claim 16 wherein said electrically conductive material comprises a metal.
Claim 20
Dependent Claim
13 words
The composite of claim 17 wherein said metal is a vacuum deposited metal.
Claim 21
Dependent Claim
14 words
The composite of claim 16 wherein said electrically conductive material comprises a metal oxide.
Claim 22
Dependent Claim
20 words
The composite of claim 16 wherein said electrically conductive material comprises a dispersion of electrically conductive materials in a binder.
Claim 23
Dependent Claim
13 words
The composite of claim 16 wherein said electrically insulative material comprises a polymer.
Claim 24
Dependent Claim
17 words
The composite of claim 21 wherein said polymer is in the form of an extruded polymeric film.
Claim 25
Dependent Claim
16 words
The composite of claim 16 wherein said zone of material transparent to microwave energy comprises paper.
Claim 26
Dependent Claim
19 words
The composite of claim 16 wherein there are up to ten zones of material capable of absorbing microwave energy.
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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) | 1993-10-08 | 1994-04-09 | 1994-10-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-10-08 | 1998-04-09 | 1998-10-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-10-08 | 2002-04-09 | 2002-10-09 | $7700.00 | Window Closed / Lapsed |