Patent US3668053A successfully refreshed from Google Patents.
US3668053A
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Article for preventing edge defect in compression stretched acrylic sheet
Assignee: Fortin Plastics Inc
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Filing: 1970-05-25
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Granted: 1972-06-06
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Expires: 1990-05-25
Abstract
Abstract An article for preventing edge defects in compression-stretched acrylic sheets comprising providing the circumferential end surfaces of an acrylic blank to be stretched with a groove substantially continuous therewith, the depth of the groove being greater than 5 percent and, preferably, being greater than about 10 percent of the initial thickness of the acrylic blank. The groove may have various configurations, e.g., V- and U-shaped configurations. Preferably, the center line of the groove lies in the plane bisecting the blank in the thickness direction.
Inventors
- 👤 Ronald L Ayres
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:44
CPC Classifications
B; B29; B29C; B29C43/00; B29C67/00; B29C67/0011; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24479; Y10T428/24488; Y10T428/24777
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
46 words
An acrylic blank defined by an upper and a lower surface and by a circumferential end surface and having an initial thickness, said circumferential end surface hAving a circumferential groove therein having a depth at least about 5 percent of said initial thickness of said blank.
Claim 2
Dependent Claim
46 words
An acrylic blank defined by an upper and a lower surface and by a circumferential end surface and having an initial thickness, said circumferential end surface hAving a circumferential groove therein having a depth at least about 5 percent of said initial thickness of said blank.
Claim 3
Dependent Claim
18 words
The acrylic blank of claim 1 wherein said circumferential groove is substantially coextensive with said circumferential end surface.
Claim 4
Dependent Claim
25 words
The acrylic blank of claim 1 wherein said depth of said groove is at least about 10 percent of said initial thickness of said blank.
Claim 5
Dependent Claim
22 words
The acrylic blank of claim 1 wherein said groove is symmetrical about a plane through the center-line of said circumferential end surfaces.
References Cited (Backward Citations)
US2201669A
Cited
US3262136A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-06-06 | 1975-12-06 | 1976-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-06 | 1979-12-06 | 1980-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-06 | 1983-12-06 | 1984-06-06 | $7700.00 | Window Closed / Lapsed |