US4144834A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Defrost indicator
Assignee: Individual
•
Filing: 1976-12-27
•
Granted: 1979-03-20
•
Expires: 1996-12-27
Abstract
Abstract A thaw-indicating device that is visibly positioned in a package of frozen food so to warn a consumer if the food item has ever been subjected to being thawed, and thus being spoiled even if refrozen subsequently; the device consisting of a transparent plastic capsule having a sealed singular compartment in one end of which there is a colorless, clear, frozen ice and in the other end of which there is a powdered dye that is soluble in water, so that if the ice melts into water due to thawing temperatures the entire interior of the capsule is visibly colored.
Inventors
- 👤 James Donegan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 23:03
CPC Classifications
G; G01; G01K; G01K11/00; G01K11/06
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
124 words
A defrost indicator for visable installation in a package of frozen food comprising in combination, a capsule formed of transparent material and comprising a single, sealed compartment inside said capsule, said capsule containing in unmixed condition a quantity of colorless frozen ice conforming in shape to a portion of said compartment, and a quantity of powdered dye of a specified color in the other portion of said compartment, said dye being soluble in liquid from which said ice is formed and capable of discoloring said frozen ice into said specified color upon melting of said ice and when a defrost condition is reached, and wherein said single, sealed compartment contains both said frozen ice and said dye at opposite end portions of said compartment.
Claim 2
Dependent Claim
124 words
A defrost indicator for visable installation in a package of frozen food comprising in combination, a capsule formed of transparent material and comprising a single, sealed compartment inside said capsule, said capsule containing in unmixed condition a quantity of colorless frozen ice conforming in shape to a portion of said compartment, and a quantity of powdered dye of a specified color in the other portion of said compartment, said dye being soluble in liquid from which said ice is formed and capable of discoloring said frozen ice into said specified color upon melting of said ice and when a defrost condition is reached, and wherein said single, sealed compartment contains both said frozen ice and said dye at opposite end portions of said compartment.
Claim 3
Dependent Claim
18 words
A defrost indicator as in claim 1 and wherein said frozen ice is frozen water and is clear.
References Cited (Backward Citations)
US1535536A
Cited
US2379459A
Cited
US2593566A
Cited
US2662018A
Cited
US2852394A
Cited
US3220259A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-03-19 | 1982-09-18 | 1983-03-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-03-19 | 1986-09-18 | 1987-03-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-03-19 | 1990-09-18 | 1991-03-20 | $7700.00 | Window Closed / Lapsed |