Patent US4495017A successfully refreshed from Google Patents.
US4495017A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for continuous production of prepreg sheets
Assignee: Sumitomo Chemical Co Ltd
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Filing: 1983-03-25
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Granted: 1985-01-22
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Expires: 2003-03-25
Abstract
Abstract The present invention relates to a process for the continuous production of prepreg sheets unidirectionally arranged in parallel which involves contacting a plurality of fiber bundles arranged unidirectionally in parallel with each other with a solvent and continuously taking up the individual fiber bundle units under tension over curved surfaces of spreader bodies, such as cylinders while in a wet state, thereby spreading out said fiber bundles over the curved surfaces by means of said tension and subsequently drying the thus-spread out fibers. The invention also contemplates impregnating the dried fiber bundles with a specified quantity of molten resin to prepare the final prepreg resin-containing sheets. According to applicants' method, the fiber bundles are spread with a solvent prior to being impregnated with a resin and this method greatly decreases the frictional resistance between the fiber bundles and the curved surfaces making it possible for the fiber bundles to be spread out by only using a slight tension.
Inventors
- 👤 Yasuaki Abe
- 👤 Mikio Hayashi
- 👤 Kousaku Asagi
- 👤 Akira Morii
- 👤 Kazutoshi Fujimura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 23:45
CPC Classifications
D; D02; D02J; D02J1/00; D02J1/18; B; B29; B29B; B29B15/00; B29B15/08; B29B15/10; B29B15/12; B29B15/122; B29C; B29C70/00; B29C70/04; B29C70/06; B29C70/10; B29C70/28; B29C70/40; B29C70/50; D04; D04H; D04H3/00; D04H3/02; D04H3/04; D04H3/08; D04H3/12
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
115 words
A process for the continuous production of prepreg sheets unidirectionally arranged in parallel which consists essentially of contacting a plurality of fiber bundles arranged unidirectionally in parallel with each other with a solvent which may contain up to 5% by weight of a sizing agent and continuously taking up said fiber bundles under tension of 33.33-250 g/1000 filaments over curved surfaces of spreader bodies, while in a wet state with said solvent to spread out said fiber bundles, drying the thus-spread out fibers by contacting them over heated drum drier bodies heated sufficiently to substantially remove all the solvent therefrom, and then impregnating the dried fiber bundles with a predetermined quantity of a molten resin.
Claim 2
Dependent Claim
115 words
A process for the continuous production of prepreg sheets unidirectionally arranged in parallel which consists essentially of contacting a plurality of fiber bundles arranged unidirectionally in parallel with each other with a solvent which may contain up to 5% by weight of a sizing agent and continuously taking up said fiber bundles under tension of 33.33-250 g/1000 filaments over curved surfaces of spreader bodies, while in a wet state with said solvent to spread out said fiber bundles, drying the thus-spread out fibers by contacting them over heated drum drier bodies heated sufficiently to substantially remove all the solvent therefrom, and then impregnating the dried fiber bundles with a predetermined quantity of a molten resin.
Claim 3
Dependent Claim
31 words
A process according to claim 1 wherein said fiber bundles, before being wet with said solvent and spread out, contain a sizing agent, and wherein said solvent removes said sizing agent.
Claim 4
Dependent Claim
30 words
A process according to claim 1 wherein the curved surfaces of said spread bodies have at least a part of said surface in the form of a column or cylinder.
Claim 5
Dependent Claim
31 words
A process according to claim 1 wherein said fiber bundle units are each spread out by more than 50%, based on the final width and thickness of the final prepreg sheet.
Claim 6
Dependent Claim
31 words
A process according to claim 1 wherein said fiber bundle units are each spread out by more than 100%, based on the final width and thickness of the final prepreg sheet.
Claim 7
Dependent Claim
44 words
A process according to claim 1 wherein said curved spreader bodies are immersed within a solvent and the fiber bundles are introduced into the solvent and contacted with the curved surfaces where they are taken up and spread over said curved surfaces under tension.
Claim 8
Dependent Claim
31 words
A process according to claim 1 wherein the curved surfaces are cylinders which rotate while the fiber bundle units are contacted with the cylinders during the spreading of said fiber bundles.
Claim 9
Dependent Claim
16 words
A process according to claim 7 in which the solvent does not contain a sizing agent.
Claim 10
Dependent Claim
37 words
A process according to claim 8 in which the fiber bundles contain 0.4% of a sizing agent prior to being contacted with a solvent and the sizing agent is removed from the fiber bundles by the solvent.
Claim 11
Dependent Claim
16 words
A process according to claim 1 in which the solvent contains 5% of a sizing agent.
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) | 1988-01-22 | 1988-07-23 | 1989-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-01-22 | 1992-07-23 | 1993-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-01-22 | 1996-07-23 | 1997-01-22 | $7700.00 | Window Closed / Lapsed |