US4421429A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Resistive substrate for thermal printing ribbons comprising a mixture of thermosetting polyimide, thermoplastic polyimide, and conductive particulate material
Assignee: IBM Information Products Corp
•
Filing: 1981-12-22
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Granted: 1983-12-20
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Expires: 2001-12-22
Abstract
Abstract Disclosed is a thermal transfer medium which comprises a mixture of a thermosetting polyimide, a thermoplastic polyimide, and graphite. It has a steel support layer and an intermediate layer of silicon dioxide. An outer layer on the steel is the thermal ink. The mixture is applied as a dispersion with a precursor of the thermosetting polyimide. The ribbon may be recoated at the typing station by applying a hot melt of the ink.
Inventors
- 👤 Arthur E. Graham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:26
CPC Classifications
B; B41; B41M; B41M5/00; B41M5/26; B41M5/382; B41M5/3825; B41J; B41J31/00; B41J31/05; Y; Y10; Y10S; Y10S428/00; Y10S428/914
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
37 words
A ribbon for non-impact thermal transfer printing comprising a thermal transfer layer and a resistive substrate which comprises a thorough mixture of a thermosetting polyimide, a thermoplastic polyimide, and an electrically significant amount of conductive, particulate material.
Claim 2
Dependent Claim
37 words
A ribbon for non-impact thermal transfer printing comprising a thermal transfer layer and a resistive substrate which comprises a thorough mixture of a thermosetting polyimide, a thermoplastic polyimide, and an electrically significant amount of conductive, particulate material.
Claim 3
Dependent Claim
19 words
The ribbon as in claim 1 which comprises a metal support layer between said transfer layer and said substrate.
Claim 4
Dependent Claim
14 words
The ribbon as in claim 1 in which said conductive, particulate material is graphite.
Claim 5
Dependent Claim
43 words
A ribbon for non-impact thermal transfer printing comprising a thermal transfer layer and a substrate comprising a mixture of thermosetting and thermoplastic polyimides and a conductive, particulate material, said substrate having a resistance in the range of between 1 ohm-cm and 10 ohm-cm.
Claim 6
Dependent Claim
43 words
A ribbon for non-impact thermal transfer printing comprising a thermal transfer layer and a substrate comprising a mixture of thermosetting and thermoplastic polyimides and a conductive, particulate material, said substrate having a resistance in the range of between 1 ohm-cm and 10 ohm-cm.
Claim 7
Dependent Claim
19 words
The ribbon as in claim 4 which comprises a metal support layer between said transfer layer and said substrate.
Claim 8
Dependent Claim
14 words
The ribbon as in claim 4 in which said conductive, particulate material is graphite.
Claim 9
Independent Claim
82 words
The method of making a thermal transfer medium comprising applying to one side of a heat-conductive lamination a mixture of a precursor of a thermosetting polyimide, a thermoplastic polyimide, and a particulate filler material dispersed in a dispersant, heating said applied mixture to expell the dispersant of said mixture, heating said applied mixture to polymerize said precursor, coating a thermal ink formula as a liquid on the other side of said lamination, and then solidifying said applied liquid as a thermal ink.
Claim 10
Independent Claim
82 words
The method of making a thermal transfer medium comprising applying to one side of a heat-conductive lamination a mixture of a precursor of a thermosetting polyimide, a thermoplastic polyimide, and a particulate filler material dispersed in a dispersant, heating said applied mixture to expell the dispersant of said mixture, heating said applied mixture to polymerize said precursor, coating a thermal ink formula as a liquid on the other side of said lamination, and then solidifying said applied liquid as a thermal ink.
Claim 11
Dependent Claim
12 words
The method as in claim 7 in which said dispersant comprises N-methyl-2-pyrrolidone.
Claim 12
Dependent Claim
19 words
The method as in claim 8 in which said dispersant also comprises an organic solvent for said thermoplastic polyimide.
Claim 13
Dependent Claim
14 words
The method as in claim 7 in which said particulate filler material is graphite.
Claim 14
Dependent Claim
14 words
The method as in claim 8 in which said particulate filler material is graphite.
Claim 15
Dependent Claim
14 words
The method as in claim 9 in which said particulate filler material is graphite.
References Cited (Backward Citations)
US2713822A
Cited
US3377598A
Cited
GB1221489A
Cited
US3551200A
Cited
US3744611A
Cited
US3868351A
Cited
US4103066A
Cited
US4236834A
Cited
US4253775A
Cited
US4309117A
Cited
US4269892A
Cited
US4345845A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-12-19 | 1987-06-20 | 1987-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-12-19 | 1991-06-20 | 1991-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-12-19 | 1995-06-20 | 1995-12-20 | $7700.00 | Window Closed / Lapsed |