EP0055024A2
Expired / Lapsed
EP
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Carbonaceous pitch, production thereof and carbon fibers therefrom
Assignee: Tonen General Sekiyu KK
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Filing: 1981-11-17
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Granted: —
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Expires: 2001-11-17
Abstract
Abstract A carbonaceous pitch suitable for production of high tensile strength, high modulus of elasticity fibers comprises 2 to 20 wt % of n-heptane-soluble component and 15 to 45 wt % of n-heptane-insoluble/benzene-soluble component. The balance is preferably only benzene insolubles comprising quinoline-solubles and quinoline-insolubles. The pitch has a softening point up to 320°C and an anisotropic phase content of at least 90 vol %. The pitch may be prepared by thermally cracking and polycondensing a heavy hydrocarbon oil or tar, precipitating anisotropic phase at 400 to 440°C without substantial increase in molecular weight, separating and subjecting the anisotropic phase to heat treatment in inert atmosphere. Carbon fibers may be produced by spinning the pitch at 280 to 370°C, rendering the fibers infusible by heating in oxidising atmosphere and then carbonising. Tensile strengths of 3 GPa and modulus in tension of 200 GPa are possible.
Inventors
- 👤 Takayuki Izumi
- 👤 Tsutomu Naito
- 👤 Tomoo Nakamura
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 06:26
CPC Classifications
C; C10; C10C; C10C3/00; D; D01; D01F; D01F9/00; D01F9/08; D01F9/12; D01F9/14; D01F9/145
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
101 words
A carbonaceous pitch composition suitable for the production of a carbon material having a high tensile strength and a high modulus of elasticity; which composition is characterized by: (i) containing 2 to 20 wt %, preferably 5 to 15 wt %, of a first component which is n-heptane-soluble, 15 to 45 wt %, preferably 15 to 35 wt %, of a second component which is n-heptane-insoluble and benzene-soluble, the balance including benzene-insoluble components; (ii) having a softening point of up to 320°C, preferably from 230 to 320°C; and (iii) having an optically anisotropic phase content of at least 90 vol %.
Claim 2
Dependent Claim
101 words
A carbonaceous pitch composition suitable for the production of a carbon material having a high tensile strength and a high modulus of elasticity; which composition is characterized by: (i) containing 2 to 20 wt %, preferably 5 to 15 wt %, of a first component which is n-heptane-soluble, 15 to 45 wt %, preferably 15 to 35 wt %, of a second component which is n-heptane-insoluble and benzene-soluble, the balance including benzene-insoluble components; (ii) having a softening point of up to 320°C, preferably from 230 to 320°C; and (iii) having an optically anisotropic phase content of at least 90 vol %.
Claim 3
Dependent Claim
57 words
A composition as claimed in claim 1, characterized in that the said balance is benzene-insoluble components constituted by quinoline-soluble components in total of 5 to 55 wt %, preferably 5 to 40 wt %, of the composition and quinoline-insoluble components in total of 20 to 70 wt %, preferably 25 to 65 wt %, of the composition.
Claim 4
Dependent Claim
39 words
A composition as claimed in claim 1 or claim 2, wherein ratios of carbon atoms in the aromatic structure to the total carbon atoms in said first and second components are both at least 0.8, preferably 0.8 to 0.95.
Claim 5
Dependent Claim
54 words
A composition as claimed in claim 2, wherein said first and second components and said quinoline-soluble and quinoline-insoluble components have respective C/H atomic ratios of at least 1.3, preferably 1.3 to 1.6; at least 1.4, preferably 1.4 to 1.7; at least 1.5, preferably 1.5 to 1.9; and up to 2.3, preferably 1.8 to 2.3.
Claim 6
Dependent Claim
36 words
A composition as claimed in claim 2 or claim 4, wherein said first and second components and quinoline-soluble and quinoline-insoluble components have number average molecular weights in the ranges of 250-700, 400-1,000, 800-2,000 and 1,500-3,000, respectively.
Claim 7
Dependent Claim
42 words
A composition as claimed in claim 2 or claim 4 or claim 5, wherein said first and second components and said quinoline-insoluble components have maximum molecular weights of no higher than 5,000, no higher than 10,000 and no higher than 30,000, respectively.
Claim 8
Dependent Claim
53 words
A composition as claimed in claim 1, wherein said second component has a C/H atomic ratio of 1.4-1.7, a carbon ratio value of 0.80-0.95, a number average molecular weight of 400-1,000 and a content of a moiety having a molecular weight of at least 5,000 of no higher than 1 percent by weight.
Claim 9
Dependent Claim
53 words
A composition as claimed in claim 2, wherein said quinoline-soluble component has a C/H atomic ratio of 1.5-1.9, a carbon ratio value of 0.80-0.95, a number average molecular weight of 800-2,000 and a content of a moiety having a molecular weight of at least 10,000 of no higher than 1 percent by weight.
Claim 10
Dependent Claim
97 words
A process for producing a carbonaceous pitch containing at least 90 vol % of optically anisotropic phase, comprising the steps of: thermally cracking and polycondensing a precursor material, preferably a heavy hydrocarbon oil, tar or pitch, to form a partially optically anisotropic phase, depositing the optically anisotropic phase at a temperature, preferably 400 to 440°C, at which the molecular weight thereof is not increased significantly, separating the deposited phase, preferably at below 400°C, and subjecting it to thermal treatment, preferably at 390 to 440°C, for a time sufficient to form at least 90 vol % anisotropic phase.
Claim 11
Dependent Claim
97 words
A process for producing a carbonaceous pitch containing at least 90 vol % of optically anisotropic phase, comprising the steps of: thermally cracking and polycondensing a precursor material, preferably a heavy hydrocarbon oil, tar or pitch, to form a partially optically anisotropic phase, depositing the optically anisotropic phase at a temperature, preferably 400 to 440°C, at which the molecular weight thereof is not increased significantly, separating the deposited phase, preferably at below 400°C, and subjecting it to thermal treatment, preferably at 390 to 440°C, for a time sufficient to form at least 90 vol % anisotropic phase.
Claim 12
Dependent Claim
15 words
A carbonaceous pitch fiber whenever produced from a composition as claimed in any preceding claim.
Claim 13
Dependent Claim
53 words
A process for producing carbon fibers, characterized by spinning the carbonaceous pitch defined in any of claims 1 to 9 at a temperature in the range 280 to 370°C to form fibers, rendering the fibers substantially infusible by heating in an oxidising atmosphere, and then carbonising the fibers, preferably in an inert atmosphere.
References Cited (Backward Citations)
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