Patent US4197283A successfully refreshed from Google Patents.
US4197283A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Carbon fibres
Assignee: BP PLC
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Filing: 1978-05-08
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Granted: 1980-04-08
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Expires: 1998-05-08
Abstract
Abstract The invention relates to a process for the manufacture of carbon or graphite fibres which comprises spinning a petroleum pitch having a β resin content of between 5 and 40%, and carbonizing the resultant fibres by heating. The pitch may have a δ resin content of between 10 and 20% and an α resin content of less than 1%. It may be produced by distilling and ageing the residue from the steam cracking of a petroleum fraction, particularly a naphtha fraction. The fibres may be given a surface oxidation between the spinning and carbonization stages. These fibres may be used in the reinforcement of plastic materials.
Inventors
- 👤 Alain Crepaux
- 👤 Anne-Marie Moutard
- 👤 Albert Bonzom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:13
CPC Classifications
D; D01; D01F; D01F9/00; D01F9/08; D01F9/12; D01F9/14; D01F9/145; D01F9/155
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
132 words
Process for the manufacture of carbon or graphite fibres from petroleum pitch comprising spinning the said pitch into fibres at a temperature higher than the softening point of the pitch and carbonising the resultant fibres by heating, characterised in that a petroleum pitch is used having a β resin content of between 5 and 40%, a δ resin content of between 10 and 20% and a α resin content of less than 1%, said pitch being further characterised by the fact that the said pitch is prepared by subjecting a steam cracking residue of a petroleum fraction to a distillation to obtain a pitch having a KS softening point of between 55° and 90° C., and ageing the pitch thermally until a softening point of between 150° and 250° C. is obtained.
Claim 2
Dependent Claim
132 words
Process for the manufacture of carbon or graphite fibres from petroleum pitch comprising spinning the said pitch into fibres at a temperature higher than the softening point of the pitch and carbonising the resultant fibres by heating, characterised in that a petroleum pitch is used having a β resin content of between 5 and 40%, a δ resin content of between 10 and 20% and a α resin content of less than 1%, said pitch being further characterised by the fact that the said pitch is prepared by subjecting a steam cracking residue of a petroleum fraction to a distillation to obtain a pitch having a KS softening point of between 55° and 90° C., and ageing the pitch thermally until a softening point of between 150° and 250° C. is obtained.
Claim 3
Dependent Claim
22 words
Process in accordance with claim 1, characterised in that the β resin content of the said pitch is between 10 and 30%.
Claim 4
Dependent Claim
82 words
Process in accordance with claim 1, characterised in that the pitch prepared by subjecting a steam cracking residue of a petroleum fraction to a distillation to obtain a pitch having a KS softening point of between 55° and 90° C., is aged thermally until a softening point of between 85° and 110° C. is obtained and then the pitch thus obtained is subjected to a supplementary thermal treatment to obtain the pitch having a softening point of between 150° and 250° C.
Claim 5
Dependent Claim
30 words
Process in accordance with claim 3, characterised in that the said supplementary thermal treatment is carried out by stripping with an inert gas at a temperature lower than 350° C.
Claim 6
Dependent Claim
32 words
Process in accordance with claim 4, characterised in that the said supplementary thermal treatment is carried out in the presence of nitrogen or argon and at a temperature lower than 300° C.
Claim 7
Dependent Claim
28 words
Process in accordance with claim 3, characterised in that the said supplementary thermal treatment is carried out by distillation in vacuo at a temperature lower than 350° C.
Claim 8
Dependent Claim
27 words
Process in accordance with claim 6, characterised in that the said distillation in vacuo is carried out at a pressure lower than 5 to 10 mm Hg.
Claim 9
Dependent Claim
29 words
Process in accordance with claim 1, characterised in that the temperature of spinning is chosen so that the pitch has a viscosity between about 60 poises and 600 poises.
Claim 10
Dependent Claim
31 words
Process in accordance with claim 1, characterised in that between the stages of spinning and carbonisation an oxidation of the fibres is carried out in the presence of an oxidising gas.
Claim 11
Dependent Claim
33 words
Process in accordance with claim 9, characterised in that the oxidation temperature is not more than 250° C. for fibres from a pitch having a softening point of between 180° and 200° C.
Claim 12
Dependent Claim
17 words
Process in accordance with claim 9, characterised in that the oxidising gas is oxygen, ozone or air.
Claim 13
Dependent Claim
27 words
Process in accordance with claim 9, characterised in that the rate of flow of oxidising gas varies between 2 liters per hour and 50 liters per hour.
Claim 14
Dependent Claim
18 words
Process in accordance with claim 1, characterised in that the carbonisation is carried out under an inert atmosphere.
Claim 15
Dependent Claim
27 words
Process in accordance with claim 13, characterised in that the carbonisation is carried out in the presence of a gas selected from among nitrogen, argon, hydrogen, helium.
Claim 16
Dependent Claim
70 words
Process in accordance with claim 13, characterised in that the carbonisation is carried out at a rate of increase of temperature of between 60° and 300° C. per hour between 250° and 400° C., at a rate of between 30° and 60° C. per hour between 400° and 450° C. and at a rate of increase of temperature between 300° and 600° C. per hour between 450° and 1000° C.
Claim 17
Dependent Claim
25 words
Process in accordance with claim 1, characterised in that the carbonisation is followed by a high-temperature thermal graphitisation treatment at between 2000° and 2500° C.
Claim 18
Dependent Claim
21 words
Process in accordance with claim 1, characterised in that the graphitisation treatment is for a period of 1 to 10 minutes.
Claim 19
Dependent Claim
34 words
Process in accordance with claim 9, characterised in that the oxidation treatment is carried out at a rate of increase of temperature of 30° to 60° C. per hour between 120° and 250° C.
Claim 20
Dependent Claim
35 words
Process in accordance with claim 14, characterised in that in the carbonisation treatment, a stage of increase of temperature is incorporated which is between 30° and 60° C. per hour between 400° and 450° C.
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) | 1983-04-08 | 1983-10-08 | 1984-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-04-08 | 1987-10-08 | 1988-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-04-08 | 1991-10-08 | 1992-04-08 | $7700.00 | Window Closed / Lapsed |