US3723607A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Surface modification of carbon fibers
Assignee: Celanese Corp
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Filing: 1970-07-16
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Granted: 1973-03-27
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Expires: 1990-07-16
Abstract
Abstract A process is provided for modifying the surface characteristics of a carbonaceous fibrous material (either amorphous carbon or graphitic carbon) and to thereby facilitate enhanced adhesion between the fibrous material and a resinous matrix material. The fibrous material is initially heat treated in an inert gaseous atmosphere, and is subsequently heated in a gaseous atmosphere which includes a substantial quantity of ozone under conditions found capable of producing the desired surface modification. Composite articles of enhanced interlaminar shear strength are formed by incorporating the fibers modified in accordance with the present process in a resinous matrix material.
Inventors
- 👤 I Kalnin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 23:22
CPC Classifications
D; D01; D01F; D01F11/00; D01F11/10; D01F11/12; D01F11/122; B; B29; B29B; B29B15/00; B29B15/08; C; C08; C08J; C08J5/00; C08J5/04; C08J5/06; Y; Y10; Y10S; Y10S264/00; Y10S264/19; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2933
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
19 words
An improved process according to claim 1 wherein said carbonaceous fibrous material includes a substantial quantity of graphitic carbon.
Claim 2
Dependent Claim
13 words
A process according to claim 1 wherein said inert gaseous atmosphere is nitrogen.
Claim 3
Dependent Claim
13 words
A process according to claim 1 wherein said inert gaseous atmosphere is argon.
Claim 4
Dependent Claim
25 words
A process according to claim 1 wherein said carbonaceous fibrous material is heated in said inert gaseous atmosphere for about 10 seconds to 10 minutes.
Claim 5
Dependent Claim
38 words
A process according to claim 1 wherein said inert gaseous atmosphere is provided at a temperature of about 1,150* to 1, 250*C., and said carbonaceous fibrous material is maintained in said atmosphere for about 30 to 180 seconds.
Claim 6
Dependent Claim
30 words
A process according to claim 1 wherein said carbonaceous fibrous material is heated in said gaseous atmosphere containing a substantial quantity of ozone for about 30 seconds to 30 minutes.
Claim 7
Dependent Claim
25 words
A process according to claim 1 wherein said gaseous atmosphere containing a substantial quantity of ozone is provided at a temperature of about 125*to 150*C.
Claim 8
Dependent Claim
32 words
A process according to claim 1 wherein said ozone is present in said gaseous atmosphere containing a substantial quantity of ozone in a concentration of about 1,500 to 110,000 parts per million.
Claim 9
Dependent Claim
23 words
A process according to claim 1 wherein substantial exposure of the fibrous material to atmospheric conditions is avoided between step (a) and (b).
Claim 10
Dependent Claim
136 words
A process for the modification of the surface characteristics of a graphitic fibrous material so as to improve its ability to bond to a resinous matrix material comprising: a. continuously passing in the direction of its length a continuous length of said graphitic fibrous material through a heating zone for about 30 seconds to 10 minutes containing an inert gaseous atmosphere selected from the group consisting of nitrogen, argon, and helium which is provided at a temperature of about 900* to 1,400*C., and b. subsequently passing in the direction of its length said continuous length of graphitic fibrous material without substantial intermediate exposure to atmospheric conditions through a heating zone for about 1 to 30 minutes containing a gaseous atmosphere which includes a substantial quantity of ozone provided at a temperature of about 75* to 175*C.
Claim 11
Dependent Claim
13 words
A process according to claim 11 wherein said inert gaseous atmosphere is nitrogen.
Claim 12
Dependent Claim
13 words
A process according to claim 11 wherein said inert gaseous atmosphere is argon.
Claim 13
Dependent Claim
38 words
A process according to claim 11 wherein said inert gaseous atmosphere is provided at a temperature of about 1,150* to 1, 250*C., and said graphitic fibrous material is maintained in said atmosphere for about 30 to 180 seconds.
Claim 14
Dependent Claim
26 words
A process according to claim 11 wherein said gaseous atmosphere containing a substantial quantity of ozone is provided at a temperature of about 125* to 150*C.
Claim 15
Dependent Claim
32 words
A process according to claim 11 wherein said ozone is present in said gaseous atmosphere containing a substantial quantity of ozone in a concentration of about 1,500 to 110,000 parts per million.
Claim 16
Dependent Claim
32 words
A process according to claim 11 wherein said ozone is present in said gaseous atmosphere containing a substantial quantity of ozone in a concentration of about 15,000 to 60,000 parts per million.
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) | 1976-03-26 | 1976-09-25 | 1977-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-26 | 1980-09-25 | 1981-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-26 | 1984-09-25 | 1985-03-27 | $7700.00 | Window Closed / Lapsed |