US5439648A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gas indicator for a package
Assignee: Sealed Air Holdings New Zealand Pty Ltd
•
Filing: 1994-05-26
•
Granted: 1995-08-08
•
Expires: 2014-05-26
Abstract
Abstract A gas indicator (11) for a modified atmosphere food package (19) comprises a series of strips (12, 13, 14, 15, 16) which progressively change colour as the proportion of carbon dioxide in the atmosphere progressively changes in magnitude due to absorption of the carbon dioxide by the food product (17) over time. The indicator (11) thus is "tuned" to indicate changing atmospheric conditions inside a see-through envelope (10) and thus the condition of the product (17) can be monitored and the package (19) is tamper evident.
Inventors
- 👤 Simon N. Balderson
- 👤 Robert J. Whitwood
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 18:00
CPC Classifications
B; B65; B65D; B65D79/00; B65D79/02; A; A23; A23B; A23B2/00; A23B2/70; A23B2/704; A23B2/708; A61; A61L; A61L2/00; A61L2/26; B65D55/00; B65D55/02; B65D55/026; G; G01; G01N; G01N33/00; G01N33/02; G01N33/48; G01N33/483; G01N33/497; Y; Y10; Y10S; Y10S435/00; Y10S435/81; Y10T; Y10T436/00; Y10T436/20; Y10T436/204998
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
61 words
A food package (19) comprising: a sealed envelope (10) containing a food product (17); a predetermined ratio of gases inserted into the envelope (10) prior to sealing; and an indicator (11) which changes color when there is a change in the concentration of at least one gas of said ratio and further changes color when the sealed envelope (10) is opened.
Claim 2
Dependent Claim
61 words
A food package (19) comprising: a sealed envelope (10) containing a food product (17); a predetermined ratio of gases inserted into the envelope (10) prior to sealing; and an indicator (11) which changes color when there is a change in the concentration of at least one gas of said ratio and further changes color when the sealed envelope (10) is opened.
Claim 3
Dependent Claim
22 words
The package (19) as claimed in claim 1, wherein the indicator (11) is applied to an inner surface of the envelope (10).
Claim 4
Dependent Claim
15 words
The package (19) as claimed in claim 2, wherein the indicator (11) is a label.
Claim 5
Dependent Claim
20 words
The package (19) as claimed in claim 2, wherein the indicator (11) comprises material primed on the said inner surface.
Claim 6
Dependent Claim
29 words
The package (19) as claimed in any one of the preceding claims, wherein the indicator (11) is protected from the product (17) by means of a gas permeable membrane.
Claim 7
Dependent Claim
21 words
The package (19) as claimed in claims 1, 2, 3, or 4, wherein said at least one gas is carbon dioxide.
Claim 8
Dependent Claim
19 words
The package (19) as claimed in any one of claims 1-4, wherein said at least one gas is oxygen.
Claim 9
Dependent Claim
17 words
The package (19) as claimed in claim 5, wherein said at least one gas is carbon dioxide.
Claim 10
Dependent Claim
16 words
The package (19) as claimed in claim 5, wherein said at least one gas is oxygen.
Claim 11
Dependent Claim
56 words
A food package (19) comprising: a sealed envelope (10) containing a food product (17); a predetermined amount of gas inserted into the envelope (10) prior to sealing; and an indicator (11) which changes color when there is a change in the concentration of said gas and further changes color when the sealed envelope (10) is opened.
Claim 12
Dependent Claim
56 words
A food package (19) comprising: a sealed envelope (10) containing a food product (17); a predetermined amount of gas inserted into the envelope (10) prior to sealing; and an indicator (11) which changes color when there is a change in the concentration of said gas and further changes color when the sealed envelope (10) is opened.
Claim 13
Dependent Claim
22 words
The package (19) as claimed in claim 10, wherein the indicator (11) is applied to an inner surface of the envelope (10).
Claim 14
Dependent Claim
15 words
The package (19) as claimed in claim 11, wherein the indicator (11) is a label.
Claim 15
Dependent Claim
19 words
The package (19) as claimed in claim 11, wherein the indicator (11) comprises material printed on said inner surface.
Claim 16
Dependent Claim
28 words
The package (19) as claimed in any one of claims 10-13, wherein the indicator (11) is protected from the product (17) by means of a gas permeable membrane.
References Cited (Backward Citations)
US3899295A
Cited
GB1492377A
Cited
US4003709A
Cited
US4285697A
Cited
US4349509A
Cited
JPS60252235A
Cited
US4772560A
Cited
US4994117A
Cited
WO1989005761A1
Cited
US5096813A
Cited
GB2234974A
Cited
JPH0483533A
Cited
JPH04151554A
Cited
US5320807A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-08-07 | 1999-02-06 | 1999-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-08-07 | 2003-02-06 | 2003-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-08-07 | 2007-02-06 | 2007-08-08 | $7700.00 | Window Closed / Lapsed |