US3633425A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Chromatic temperature indicator
Assignee: Meditech Energy and Environmental Corp
•
Filing: 1970-01-02
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Granted: 1972-01-11
•
Expires: 1990-01-02
Abstract
Abstract A fever indicator which can be visually monitored by observation of a temperature-dependent color-changing characteristic thereof. Said indicator is advantageously formed of a mixture of liquid crystals, e.g., a mixture formed of cholesteryl pelargonate and cholesteryl oleyl carbonate and maintained in contact with a porous and inert, but translucent, material. The mixture is incorporated into an apparatus comprising a reservoir, which can be formed of the porous inert material, and normally includes a fastening means for holding said reservoir in close contact with the body of a patient. Where a black background is required to aid the visibility of the color change, graphite-type carbon powders have been found most advantageous for use.
Inventors
- 👤 Robert A Sanford
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 15:05
CPC Classifications
G; G01; G01K; G01K11/00; G01K11/12; G01K11/16
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
11 words
a mass of porous translucent material immersed within said mixture, and
Claim 2
Dependent Claim
20 words
A temperature-sensing apparatus as defined in claim 1 wherein said translucent, surface-making material is a quantity of inert translucent beads.
Claim 3
Dependent Claim
16 words
placing the coated material on an object the temperature of which is to be sensed, and
Claim 4
Dependent Claim
7 words
observing the color change of said mixture.
Claim 5
Dependent Claim
16 words
A temperature-sensing apparatus as defined in claim 2 wherein said translucent, surface-making material is foam material.
Claim 6
Dependent Claim
8 words
means for fastening said reservoir to a body.
Claim 7
Dependent Claim
15 words
A temperature-sensing apparatus as defined in claim 3 wherein said foam is a glass foam.
Claim 8
Dependent Claim
15 words
A temperature-sensing apparatus as defined in claim 3 wherein said foam is a plastic foam.
Claim 9
Dependent Claim
28 words
Apparatus as described in claim 1 wherein said mixture comprises, in addition from about 0.3 to about 20 percent by weight of particulate graphitized carbon or graphite powder.
Claim 10
Dependent Claim
28 words
A temperature-sensing apparatus as defined in claim 6 wherein said mixture of liquid crystals comprises at least 50 percent cholesteryl pelargonate and the balance comprises cholesteryl oleyl carbonate.
Claim 11
Dependent Claim
21 words
Apparatus as defined in claim 1 comprising a plurality of said mixtures, each adapted to change color at a different temperature.
Claim 12
Dependent Claim
33 words
Apparatus as defined in claim 1 wherein said cholesteric liquid crystal mixture is formed of cholesteryl pelargonate and cholesteryl oleyl carbonate, the former forming at least 50 percent by weight of said composition.
Claim 13
Dependent Claim
19 words
A temperature-sensing apparatus as defined in claim 1 wherein said mass is fused together to form a reticulated structure.
Claim 14
Dependent Claim
22 words
A temperature-sensing apparatus comprising a reservoir containing therein a mixture of cholesteric liquid crystals, said reservoir being formed of a translucent foam.
Claim 15
Dependent Claim
33 words
A temperature-sensing apparatus formed of a reservoir comprising a mixture of cholesteric liquid, said reservoir being formed of a translucent plastic foam having an average pore diameter of less than about 10 millimeters.
Claim 16
Dependent Claim
27 words
Apparatus as defined in claim 1 wherein said translucent mass is composed of transparent beads having an average diameter between about 0.01 millimeters and about 10 millimeters.
Claim 17
Dependent Claim
15 words
A thermally responsive, temperature-indicating mixture comprising a mixture of cholesteric liquid crystals and translucent particles.
Claim 18
Dependent Claim
29 words
A mixture as defined in claim 14 comprising, additionally, from about 0.3 to about 20 percent by weight, based on the cholesteric liquid crystals, of a graphitized carbon powder.
Claim 19
Dependent Claim
32 words
A mixture as defined in claim 14 wherein said cholesteric liquid crystals mixture is formed of cholesteryl pelargonate and cholesteryl oleyl carbonate, the former forming at least 50 percent of said composition.
Claim 20
Dependent Claim
24 words
A thermally responsive, temperature-indicating mixture as defined in claim 14 wherein said particles are between 0.01 millimeters and about 10 millimeters in mean diameter.
Claim 21
Dependent Claim
19 words
An improved process for visually sensing a temperature by use of thermally sensitive, color-responsive chemicals comprising the steps of
Claim 22
Dependent Claim
17 words
A process as defined in claim 18 wherein some graphitic carbon powder is included in said mixture.
Claim 23
Dependent Claim
34 words
A process as defined in claim 18 wherein the liquid crystals are cholesteryl pelargonate and cholesteryl oleyl carbonate, the former forming at least 50 percent by weight of the liquid crystals in the mixture.
Claim 24
Dependent Claim
19 words
A process as defined in claim 18 wherein said porous material is formed of a mass of translucent particles.
Claim 25
Dependent Claim
20 words
A process as defined in claim 18 wherein said porous material is a reticulated foam formed of a translucent material.
References Cited (Backward Citations)
US3243303A
Cited
US3409404A
Cited
US3533399A
Cited
US3441513A
Cited
US3440882A
Cited
US3524726A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-10 | 1975-07-12 | 1976-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-10 | 1979-07-12 | 1980-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-10 | 1983-07-12 | 1984-01-11 | $7700.00 | Window Closed / Lapsed |