US4138357A
Expired / Lapsed
US
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Thermochromic material
Assignee: Fujifilm Holdings Corp
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Filing: 1977-05-12
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Granted: 1979-02-06
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Expires: 1997-05-12
Abstract
Abstract A thermochromic material, and a heat sensitive recording material containing the same, comprising a substantially colorless electron donating color former capable of forming a color upon reacting with an electron accepting acid compound and a compound represented by the general formula HOArCOOR wherein R represents an organic group having 1 to about 10 carbon atoms and Ar represents an aromatic nucleus.
Inventors
- 👤 Akira Igarashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:32
CPC Classifications
B; B41; B41M; B41M5/00; B41M5/26; B41M5/30; B41M5/333; B41M5/3333; B41M5/3335; Y; Y10; Y10S; Y10S252/00; Y10S252/962
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
125 words
A thermochromic material comprising a mixture of (1) a substantially colorless electron donating color former capable of forming a color upon reacting with an electron accepting acidic material, and (2) at least one compound represented by the following general formula (I) ho--ar--COOR (I) wherein R represents an alkyl group containing 2 to 8 carbon atoms, a phenyl group substituted with a methoxy group, a benzyl group or a napthyl group, and Ar represents a benzene nucleus, or a benzene nucleus substituted with one or two of a nitro group, an alkyl group containing 1 to 4 carbon atoms, a methoxy group or a halogen atom, said compound being solid at room temperature and having a melting point between about 50° C. and about 200° C.
Claim 2
Dependent Claim
125 words
A thermochromic material comprising a mixture of (1) a substantially colorless electron donating color former capable of forming a color upon reacting with an electron accepting acidic material, and (2) at least one compound represented by the following general formula (I) ho--ar--COOR (I) wherein R represents an alkyl group containing 2 to 8 carbon atoms, a phenyl group substituted with a methoxy group, a benzyl group or a napthyl group, and Ar represents a benzene nucleus, or a benzene nucleus substituted with one or two of a nitro group, an alkyl group containing 1 to 4 carbon atoms, a methoxy group or a halogen atom, said compound being solid at room temperature and having a melting point between about 50° C. and about 200° C.
Claim 3
Dependent Claim
23 words
The thermochromic material of claim 1, wherein the steric relationship between said HO-- group and said --COOR group is an o- or p-relationship.
Claim 4
Dependent Claim
29 words
The thermochromic material of claim 1, wherein said color former is a triaryl methane derivative, a diaryl methane derivative, a xanthene compound, a thiazine compound or a spiropyran compound.
Claim 5
Dependent Claim
33 words
The thermochromic material of claim 1, wherein said compound represented by the general formula (I) has the general formula ##STR4## wherein R 1 represents an alkyl group containing 2 to 8 carbon atoms.
Claim 6
Dependent Claim
18 words
A thermographic recording material comprising a support having thereon a layer of the thermochromic material of claim 1.
Claim 7
Dependent Claim
24 words
The thermographic recording material of claim 5, wherein the steric relationship between said HO-- group and said --COOR group is an o- or p-relationship.
Claim 8
Dependent Claim
30 words
The thermographic recording material of claim 5, wherein said color former is a triaryl methane derivative, a diaryl methane derivative, a xanthene compound, a thiazine compound or a spiropyran compound.
Claim 9
Dependent Claim
34 words
The thermographic recording material of claim 5, wherein said compound represented by the general formula (I) has the general formula ##STR5## wherein R 1 represents an alkyl group containing 2 to 8 carbon atoms.
Claim 10
Dependent Claim
15 words
The thermochromic material of claim 1, wherein said mixture is charged in a transparent cell.
Claim 11
Dependent Claim
22 words
The thermochromic recording material of claim 5, wherein said support has thereon a layer containing an agent rendering the layer electrically conductive.
Claim 12
Dependent Claim
20 words
The thermochromic recording material of claim 10, wherein said agent is cuprous iodide, stannons oxide, zinc oxide or metallic powders.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-02-05 | 1982-08-07 | 1983-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-02-05 | 1986-08-07 | 1987-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-02-05 | 1990-08-07 | 1991-02-06 | $7700.00 | Window Closed / Lapsed |