US4513048A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Webbed multiple sheets
Assignee: Roehm GmbH Darmstadt
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Filing: 1983-08-31
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Granted: 1985-04-23
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Expires: 2003-08-31
Abstract
Abstract Webbed multiple sheets comprising two substantially parallel, substantially plane polymethylmethacrylate outer layers and at least one center layer between said outer layers, wherein said outer layers and said center layer are bonded together into one piece by webs and wherein said center layer or layers comprise a thermoplastic material having increased tenacity, increased zero viscosity or a combination thereof in molten condition as compared with the material of said outer layers, thereby reducing sagging of said center layer or layers during extrusion.
Inventors
- 👤 Peter Kaube
- 👤 Karl-Heinz Schanz
- 👤 Heinz Vetter
- 👤 Jens Muller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:40
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/03; B29C48/07; B29C48/08; B29C48/09; B29C48/11; B29C48/16; B29C48/25; B29C48/30; B29C48/305; B29C48/307; B29C49/00; B29C49/0015; B29C51/00; B29C51/006; B32; B32B; B32B27/00; B32B27/06; B32B27/08; B32B27/30; B32B27/308; B32B27/36; B32B27/365; B32B3/00; B32B3/10; B32B3/12; B32B7/00; B32B7/02; B32B7/022; E; E04; E04C; E04C2/00; E04C2/30; E04C2/34; E04C2/54; E04C2/543; B29C48/001; B29C48/0017; B29K; B29K2033/00; B29K2033/04; B29K2033/12; B29L; B29L2024/00; B29L2024/006; B29L2031/00; B29L2031/60; B32B2333/00; B32B2333/04; B32B2333/12; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24479; Y10T428/2457; Y10T428/24744; Y10T428/24942; Y10T428/26; Y10T428/31504; Y10T428/31507; Y10T428/3154; Y10T428/31544; Y10T428/31786; Y10T428/31797; Y10T428/31855
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
107 words
Webbed multiple sheets comprising two substantially parallel, substantially plane polymethylmethacrylate outer layers and at least one center layer between said outer layers, wherein said outer layers and said center layers are bonded together into one piece by webs and wherein said said center layer or layers comprise a thermoplastic material having increased tenacity, increased zero viscosity or a combination thereof in molten condition, as compared with the material of said outer layers, thereby reducing sagging of said center layer or layers during extrusion, and wherein said thermoplastic material of said center layer or layers is selected from the group consisting of polycarbonates, polysulfones, thermoplastic polyesters and fluoropolymers.
Claim 2
Dependent Claim
107 words
Webbed multiple sheets comprising two substantially parallel, substantially plane polymethylmethacrylate outer layers and at least one center layer between said outer layers, wherein said outer layers and said center layers are bonded together into one piece by webs and wherein said said center layer or layers comprise a thermoplastic material having increased tenacity, increased zero viscosity or a combination thereof in molten condition, as compared with the material of said outer layers, thereby reducing sagging of said center layer or layers during extrusion, and wherein said thermoplastic material of said center layer or layers is selected from the group consisting of polycarbonates, polysulfones, thermoplastic polyesters and fluoropolymers.
Claim 3
Dependent Claim
19 words
The webbed multiple sheets of claim 1, wherein the thermoplastic material of said center layer or layers is polycarbonate.
Claim 4
Dependent Claim
21 words
The webbed multiple sheets of claim 2, wherein the thermoplastic material of said center layer or layers is bisphenol A polycarbonate.
Claim 5
Dependent Claim
24 words
The webbed multiple sheets of claim 2, wherein the thermoplastic material of said center layer or layers is methylenebisphenol polycarbonate or dihydroxydiphenyl ether polycarbonate.
Claim 6
Dependent Claim
20 words
The webbed multiple sheets of claim 1, wherein said fluoropolymers comprise polyvinylidene fluoride, polychlorotrifluoroethylene or copolymers of tetrafluoroethylene and hexafluoropropylene.
Claim 7
Dependent Claim
25 words
The webbed multiple sheets of claim 1, wherein the thickness of said center layer or layers is in the range of 0.03 to 0.5 mm.
References Cited (Backward Citations)
US3707009A
Cited
US3748214A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-04-22 | 1988-10-22 | 1989-04-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-04-22 | 1992-10-22 | 1993-04-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-04-22 | 1996-10-22 | 1997-04-23 | $7700.00 | Window Closed / Lapsed |