Patent US3670059A successfully refreshed from Google Patents.
US3670059A
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US
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Method of producing a skin-covered foamed thermoplastic
Assignee: Solo Cup Operating Corp
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Filing: 1969-12-24
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Granted: 1972-06-13
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Expires: 1989-12-24
Abstract
Abstract Method of producing foamed thermoplastic material having a lowdensity core and at least one integral, high-density, thin skin, the material being suitable for the production of threedimensionally formed articles on a continuous basis. A narrow strip of the thermoplastic material is extruded at a high linear rate from an arcuate mouth die, immediately surface-chilled to produce the skin, and laterally expanded over a curved mandrel to avoid distortions such as wrinkling. Operating parameters are critically controlled.
Inventors
- 👤 Thomas W Winstead
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:20
CPC Classifications
B; B29; B29C; B29C44/00; B29C44/34; B29C44/36; B29C44/46; B29C44/50; B29C44/505; B29K; B29K2105/00; B29K2105/04; B29K2105/043; B29K2995/00; B29K2995/0037; B29K2995/005; B29K2995/0053; B29L; B29L2007/00; B29L2007/008; Y; Y10; Y10S; Y10S264/00; Y10S264/14; Y10S428/00; Y10S428/91; Y10T; Y10T428/00; Y10T428/24; Y10T428/24942; Y10T428/2495; Y10T428/24967; Y10T428/249921; Y10T428/249953; Y10T428/249987; Y10T428/249988; Y10T428/249989
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
18 words
A method in accordance with claim 1, wherein said spreading comprises biaxially orienting the molecules of said skin.
Claim 2
Dependent Claim
28 words
A method in accordance with claim 1, wherein said spreading is accomplished by passing the extrudate over a mandrel spaced about 2 to 3 inches from said die.
Claim 3
Dependent Claim
33 words
A method in accordance with claim 1, wherein the blowing agent is volatile, and wherein said spreading is accomplished while said blowing agent remains under sufficient pressure to provide plasticity for said extrudate.
References Cited (Backward Citations)
US3311681A
Cited
NL291940A
Cited
US3317363A
Cited
US3426111A
Cited
US3422172A
Cited
US3391051A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-06-13 | 1975-12-13 | 1976-06-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-13 | 1979-12-13 | 1980-06-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-13 | 1983-12-13 | 1984-06-13 | $7700.00 | Window Closed / Lapsed |