Invalidity dossier
US 4857379
Sheetlike structure of fibers, especially as a reinforcement for plastics components
Current assignee: Verseidag Industrietextilien GmbH
Added 9/21/2026, 9:32:08 AM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US 4,857,379 A
Title: Sheetlike structure of fibers, especially as a reinforcement for plastics components
Patent number: US4857379A
Assignee: Verseidag Industrietextilien GmbH (original and current assignee per the listing)
Inventor(s): Margret Plontges; Herbert Cox
Key dates (as listed):
- Priority date: 1986-10-24 (claimed from DE19863636300)
- Further priority claimed 1987-04-03 (DE19873711213)
- Filing date: 1987-10-19
- Publication/grant date: 1989-08-15
- Anticipated expiration: 2007-10-19; status "Expired – Fee Related"
Purpose (stated in the supplied text): The invention relates to a sheetlike structure of fibers useful as a reinforcement for plastics components, comprising plastics threads lying in the warp and weft directions. Its stated object is to provide a two-dimensional structure that, with low weight and relatively low manufacturing costs, is readily deformable and thus usable in diverse ways as a reinforcement.
Plain-language scope (from the supplied definitions and figures): The structure is built from plastics threads running in warp and weft directions, crossing one another (FIG. 1 shows a plan view of a laid fabric of crossing threads; FIG. 2 concerns a bonding arrangement). In use, the sheetlike fiber structure is held taut and then heated — either by a heat source or by application of a hot plastics material — so that it shrinks; because the reinforcement is fixed (held taut), tension persists in the reinforced plastics component, producing a prestressed reinforcement.
Classifications (selected): B29C70/10, B29C70/16, B29C70/22 (fibrous reinforcements, 2D oriented structures); D03D15/567 (shapes/effects upon shrinkage); D04B21/14–21/16; B63H9/0678 (laminated sails); plus various Y10T fabric/strand index codes including heat-shrinkable strand.
Source: https://patents.google.com/patent/US4857379/en
What the excerpt does not establish: The supplied text is an excerpt (figures/images and portions of the description are omitted). It does not provide the full claims, the complete written description, detailed thread materials or dimensions, the bonding method of FIG. 2, or examples. Claims scope, prosecution history, validity, ownership transfers, and prior art are not established here; this overview does not address them.
Generated 10/1/2026, 10:02:13 PM
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Litigation summary
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PTAB challenges
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Assignment history
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Prior art
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Obviousness
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Extensions
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Derivative works
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