US5928555A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microwave food scorch shielding
Assignee: General Mills Inc
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Filing: 1998-01-20
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Granted: 1999-07-27
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Expires: 2018-01-20
Abstract
Abstract A microwave container which morphs from a relatively microwave transparent condition to a relatively microwave blocking condition in response to microwave irradiation. The container wall section has a plurality of discrete, unconnected microwave reflective material elements initially permitting the transmission of microwave energy into the container and either a microwave absorptive material or a thermally responsive material active to coalesce the microwave reflective material elements into a connected array or pattern to block the transmission of microwave energy from entering the container after absorbing a predetermined amount of microwave energy.
Inventors
- 👤 Young Hwa Kim
- 👤 Hong Ji
- 👤 Victor Karpov
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:39
CPC Classifications
B; B65; B65D; B65D81/00; B65D81/34; B65D81/3446; B65D2581/00; B65D2581/34; B65D2581/3437; B65D2581/3439; B65D2581/344; B65D2581/3443; B65D2581/3463; B65D2581/3464; B65D2581/3486; B65D2581/3489; Y; Y10; Y10S; Y10S99/00; Y10S99/14
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
139 words
Apparatus for shielding foodstuffs from scorching in a microwave field comprising: a) a generally microwave transparent base material forming a generally enclosing container for foodstuffs: b) an energy reactive material located on the base material and having: i) an initial configuration of a plurality of discrete, separated elements of microwave reflective material individually sized and sufficiently spaced apart to allow transmission of microwave energy into the container to heat foodstuffs located within the container; and ii) a final configuration wherein a substantial majority of the discrete, separated elements come into contact with each other to form a continuously extending arrangement substantially blocking transmission of microwave energy into the container to prevent scorching of the foodstuff wherein the energy reactive material undergoes a transition from the initial configuration to the final configuration after a predetermined exposure to the microwave energy.
Claim 2
Dependent Claim
139 words
Apparatus for shielding foodstuffs from scorching in a microwave field comprising: a) a generally microwave transparent base material forming a generally enclosing container for foodstuffs: b) an energy reactive material located on the base material and having: i) an initial configuration of a plurality of discrete, separated elements of microwave reflective material individually sized and sufficiently spaced apart to allow transmission of microwave energy into the container to heat foodstuffs located within the container; and ii) a final configuration wherein a substantial majority of the discrete, separated elements come into contact with each other to form a continuously extending arrangement substantially blocking transmission of microwave energy into the container to prevent scorching of the foodstuff wherein the energy reactive material undergoes a transition from the initial configuration to the final configuration after a predetermined exposure to the microwave energy.
Claim 3
Dependent Claim
17 words
The apparatus of claim 1 wherein the transition is a phase change of the energy reactive material.
Claim 4
Dependent Claim
40 words
The apparatus of claim 1 wherein the energy reactive material is a carrier with microwave reflective material initially dispersed therein and the transition acts on the carrier to cause the microwave reflective material to form a generally microwave reflective layer.
Claim 5
Dependent Claim
104 words
The apparatus of claim 1 further comprising c) an interrupted pattern of microwave reflective elements having interstices therebetween; and wherein the energy reactive material comprises elements located in the interstices between the elements of the interrupted pattern of microwave reflective material and initially spaced apart therefrom and further wherein the transition to the final configuration occurs upon the energy reactive elements in the interstices connecting interruptions in the pattern of the microwave reflective material such that the pattern becomes substantially uninterrupted and wherein the pattern is sized in the final configuration to substantially block the passage of microwave energy therethrough to prevent scorching thereafter.
Claim 6
Dependent Claim
17 words
The apparatus of claim 1 wherein the predetermined exposure to microwave energy corresponds to a predetermined temperature.
Claim 7
Dependent Claim
16 words
The apparatus of claim 1 wherein the energy reactive material reacts to the microwave energy directly.
Claim 8
Dependent Claim
24 words
The apparatus of claim 1 wherein the energy reactive material reacts at a predetermined elevated temperature resulting from the predetermined exposure to microwave energy.
Claim 9
Dependent Claim
136 words
Apparatus for shielding foodstuffs from scorching in a microwave field comprising: a) a generally microwave transparent base material forming a generally enclosing container for foodstuffs; b) a thermally reactive material located on the base material and having: i) an initial configuration of a plurality of discrete, separated elements of microwave reflective material individually sized and sufficiently spaced apart to allow transmission of microwave energy into the container to heat foodstuffs located within the container; and ii) a final configuration wherein a substantial majority of the discrete, separated elements come into contact with each other to form a continuously extending arrangement substantially blocking transmission of microwave energy into the container to prevent scorching of the foodstuff wherein the thermally reactive material undergoes a transition from the initial configuration to the final configuration upon reaching a predetermined temperature.
Claim 10
Dependent Claim
136 words
Apparatus for shielding foodstuffs from scorching in a microwave field comprising: a) a generally microwave transparent base material forming a generally enclosing container for foodstuffs; b) a thermally reactive material located on the base material and having: i) an initial configuration of a plurality of discrete, separated elements of microwave reflective material individually sized and sufficiently spaced apart to allow transmission of microwave energy into the container to heat foodstuffs located within the container; and ii) a final configuration wherein a substantial majority of the discrete, separated elements come into contact with each other to form a continuously extending arrangement substantially blocking transmission of microwave energy into the container to prevent scorching of the foodstuff wherein the thermally reactive material undergoes a transition from the initial configuration to the final configuration upon reaching a predetermined temperature.
Claim 11
Dependent Claim
12 words
The apparatus of claim 8 wherein the thermally reactive material is metal.
Claim 12
Dependent Claim
17 words
The apparatus of claim 9 wherein the metal at least partially melts to form the final configuration.
Claim 13
Dependent Claim
16 words
The apparatus of claim 8 wherein the thermally reactive material is a carrier containing metal particles.
Claim 14
Dependent Claim
13 words
The apparatus of claim 11 wherein the thermally reactive material is a solvent.
Claim 15
Dependent Claim
15 words
The apparatus of claim 12 wherein the metal particles precipitate to form the final configuration.
Claim 16
Dependent Claim
25 words
The apparatus of claim 8 wherein the thermally reactive material further comprises metal particles which at least touch each other to form the final configuration.
Claim 17
Dependent Claim
17 words
The apparatus of claim 8 wherein the thermally reactive material is powder coated on the base material.
Claim 18
Independent Claim
149 words
A method of shielding foodstuffs from scorching in a microwave field comprising the steps of: a) forming a generally enclosing container of a generally microwave transparent material for containing foodstuffs; b) forming an energy reactive material layer on the base material in an initial configuration of a plurality of discrete, separated elements of microwave reflective material individually sized and sufficiently spaced apart to allow transmission of microwave energy into the container to heat foodstuffs located within the container; and c) applying microwave energy to the container such that the energy reactive material morphs to a final configuration wherein a substantial majority of the discrete, separated elements come into contact with each other to form a continuously extending arrangement substantially blocking transmission of microwave energy into the container to prevent scorching of the foodstuffs within the container upon the energy reactive layer receiving a predetermined exposure to the microwave energy.
Claim 19
Independent Claim
149 words
A method of shielding foodstuffs from scorching in a microwave field comprising the steps of: a) forming a generally enclosing container of a generally microwave transparent material for containing foodstuffs; b) forming an energy reactive material layer on the base material in an initial configuration of a plurality of discrete, separated elements of microwave reflective material individually sized and sufficiently spaced apart to allow transmission of microwave energy into the container to heat foodstuffs located within the container; and c) applying microwave energy to the container such that the energy reactive material morphs to a final configuration wherein a substantial majority of the discrete, separated elements come into contact with each other to form a continuously extending arrangement substantially blocking transmission of microwave energy into the container to prevent scorching of the foodstuffs within the container upon the energy reactive layer receiving a predetermined exposure to the microwave energy.
Claim 20
Dependent Claim
21 words
The method of claim 16 wherein the energy reactive layer is applied to the base layer by printing a microcircuit thereon.
Claim 21
Dependent Claim
25 words
The method of claim 17 wherein the microcircuit contains elements reactive to an elevated temperature to complete the microcircuit and form a microwave shielding layer.
Claim 22
Dependent Claim
19 words
The method of claim 16 wherein the energy reactive layer is applied to the base layer by powder coating.
Claim 23
Dependent Claim
40 words
The method of claim 19 wherein the powder coating includes microwave reflective particles dispersed and generally unconnected in the initial configuration and further wherein the microwave reflective particles join together in the final configuration to form a microwave shielding layer.
Claim 24
Dependent Claim
21 words
The method of claim 16 wherein the energy reactive layer is a solvent containing dispersed and generally unconnected microwave reflective particles.
Claim 25
Dependent Claim
26 words
The method of claim 21 wherein the solvent is evaporated in step c), causing the microwave reflective particles to precipitate and form a microwave shielding layer.
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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) | 2002-07-26 | 2003-01-25 | 2003-07-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-07-26 | 2007-01-25 | 2007-07-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-07-26 | 2011-01-25 | 2011-07-27 | $7700.00 | Window Closed / Lapsed |