Patent US4443324A successfully refreshed from Google Patents.
US4443324A
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Low melting mesophase pitches
Assignee: EIDP Inc
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Filing: 1982-06-14
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Granted: 1984-04-17
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Expires: 2002-06-14
Abstract
Abstract A low melting point, low molecular weight, heptane insoluble, 1,2,4-trichlorobenzene soluble mesophase pitch useful in carbon fiber spinning as such or as a plasticizer in a carbon fiber spinning composition is obtained by heating chrysene, triphenylene or paraterphenyl as well as mixtures thereof and hydrocarbon fractions containing the same, dissolving the resulting heat treated material with 1,2,4-trichlorobenzene, and separating the insolubles, and then contacting the 1,2,4-trichlorobenzene soluble fraction with a sufficient amount of heptane to precipitate the low melting point, low molecular weight mesophase pitch.
Inventors
- 👤 Russell J. Diefendorf
- 👤 Shih-Heui Chen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 18:28
CPC Classifications
C; C10; C10C; C10C1/00; C10C3/00; D; D01; D01F; D01F9/00; D01F9/08; D01F9/12; D01F9/14; D01F9/145
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
79 words
A low melting, low molecular weight, heptane insoluble, 1,2,4-trichlorobenzene soluble mesophase pitch having a melting point of less than about 250° C. and a molecular weight of less than about 1000 prepared by the method which comprises heating a feed material selected from the group consisting of chrysene, triphenylene, and para-terphenyl, dissolving the heated material with 1,2,4-trichlorobenzene and recovering the soluble portion therefrom contacting the resulting 1,2,4-trichlorobenzene solution with heptane to precipitate said heptane insoluble, 1,2,4-trichlorobenzene soluble mesophase pitch.
Claim 2
Dependent Claim
79 words
A low melting, low molecular weight, heptane insoluble, 1,2,4-trichlorobenzene soluble mesophase pitch having a melting point of less than about 250° C. and a molecular weight of less than about 1000 prepared by the method which comprises heating a feed material selected from the group consisting of chrysene, triphenylene, and para-terphenyl, dissolving the heated material with 1,2,4-trichlorobenzene and recovering the soluble portion therefrom contacting the resulting 1,2,4-trichlorobenzene solution with heptane to precipitate said heptane insoluble, 1,2,4-trichlorobenzene soluble mesophase pitch.
Claim 3
Dependent Claim
16 words
The pitch of claim 1 also characterized by a C/H ratio of about 1.5 to 1.7.
Claim 4
Independent Claim
60 words
A method of making a low melting, low molecular weight, heptane insoluble, 1,2,4-trichlorobenzene soluble mesophase pitch which comprises heating a feed material selected from the group consisting of chrysene, triphenylene, and para-terphenyl, dissolving the heated material with 1,2,4-trichlorobenzene and recovering the soluble portion therefrom contacting the resulting 1,2,4-trichlorobenzene solution with heptane to precipitate said heptane insoluble, 1,2,4-trichlorobenzene soluble mesophase pitch.
Claim 5
Independent Claim
60 words
A method of making a low melting, low molecular weight, heptane insoluble, 1,2,4-trichlorobenzene soluble mesophase pitch which comprises heating a feed material selected from the group consisting of chrysene, triphenylene, and para-terphenyl, dissolving the heated material with 1,2,4-trichlorobenzene and recovering the soluble portion therefrom contacting the resulting 1,2,4-trichlorobenzene solution with heptane to precipitate said heptane insoluble, 1,2,4-trichlorobenzene soluble mesophase pitch.
Claim 6
Dependent Claim
11 words
The method of claim 3 wherein said feed material is chrysene.
Claim 7
Dependent Claim
11 words
The method of claim 3 wherein said feed material is triphenylene.
Claim 8
Dependent Claim
11 words
The method of claim 3 wherein said feed material is paraterphenyl.
Claim 9
Dependent Claim
20 words
The method of claim 3 wherein said heating is effected by heat soaking at a temperature above about 300° C.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-04-17 | 1987-10-17 | 1988-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-04-17 | 1991-10-17 | 1992-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-04-17 | 1995-10-17 | 1996-04-17 | $7700.00 | Window Closed / Lapsed |