Patent US4528087A successfully refreshed from Google Patents.
US4528087A
Expired / Lapsed
US
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Process for producing mesophase pitch
Assignee: Mitsubishi Chemical Corp
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Filing: 1983-03-08
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Granted: 1985-07-09
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Expires: 2003-03-08
Abstract
Abstract Mesophase pitch containing quinoline soluble mesophase is produced from a pitch having a specific aromatic hydrogen content with a short heat treatment time without conducting any special treatment such as extraction.
Inventors
- 👤 Haruo Shibatani
- 👤 Kunimasa Takahashi
- 👤 Takashi Kameda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 18:32
CPC Classifications
D; D01; D01F; D01F9/00; D01F9/08; D01F9/12; D01F9/14; D01F9/145; C; C10; C10C; C10C3/00; C10C3/002
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
57 words
A process for producing mesophase pitch wherein about 40% or more of the mesophase in said pitch is quinoline soluble mesophase, which consists of heating a pitch having an aromatic hydrogen content of 50-90% at a temperature in the range of 430°-550° C. while passing an inert gas thereover until at least 40% of mesophase is formed.
Claim 2
Dependent Claim
57 words
A process for producing mesophase pitch wherein about 40% or more of the mesophase in said pitch is quinoline soluble mesophase, which consists of heating a pitch having an aromatic hydrogen content of 50-90% at a temperature in the range of 430°-550° C. while passing an inert gas thereover until at least 40% of mesophase is formed.
Claim 3
Dependent Claim
26 words
The process for producng mesophase pitch according to claim 1 wherein 60% or more of the mesophase contained in the mesophase pitch is quinoline soluble mesophase.
Claim 4
Dependent Claim
26 words
The process for producing mesophase pitch according to claim 1 wherein 70% or more of the mesophase contained in the mesophase pitch is quinoline soluble mesophase.
Claim 5
Dependent Claim
18 words
The process for producing mesophase pitch according to claim 1 wherein said mesophase pitch comprises 70-100% of mesophase.
Claim 6
Dependent Claim
18 words
The process for producing mesophase pitch according to claim 1 wherein said mesophase pitch comprises 90-100% of mesophase.
Claim 7
Dependent Claim
53 words
The process for producing mesophase pitch according to claim 1 wherein the pitch having an aromatic hydrogen content of 50-90% is produced by heating at a temperature of 400°-520° C. in the presence of hydrogen at a pressure of 5-250 kg/cm 2 , a residual oil obtained by the decomposition of petroleum fractions.
Claim 8
Dependent Claim
29 words
The process for producing mesophase pitch according to claim 6 wherein the residual oil is that formed when producing ethylene by the pyrolysis of petroleum fractions at 700°-1000° C.
Claim 9
Dependent Claim
54 words
A process for producing mesophase pitch wherein about 40% or more of the mesophase in said pitch is quinoline soluble mesophase, which consists of heating a pitch having an aromatic hydrogen content of 50-90% at a temperature in the range of 430°-550° C. under reduced pressure until at least 40% of mesophase is formed.
Claim 10
Dependent Claim
54 words
A process for producing mesophase pitch wherein about 40% or more of the mesophase in said pitch is quinoline soluble mesophase, which consists of heating a pitch having an aromatic hydrogen content of 50-90% at a temperature in the range of 430°-550° C. under reduced pressure until at least 40% of mesophase is formed.
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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) | 1988-07-08 | 1989-01-07 | 1989-07-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-08 | 1993-01-07 | 1993-07-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-08 | 1997-01-07 | 1997-07-09 | $7700.00 | Window Closed / Lapsed |