US4173612A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Extrusion process for thermoplastic rubber film
Assignee: JPMorgan Chase Bank NA
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Filing: 1977-11-03
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Granted: 1979-11-06
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Expires: 1997-11-03
Abstract
Abstract Thermoplastic rubber containing minor amounts of amorphous polypropylene is extruded into films. The films retain characteristic elastomeric properties of pure rubber, but are significantly more processable owing to the presence of the amorphous polypropylene.
Inventors
- 👤 William G. F. Kelly
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:09
CPC Classifications
B; B29; B29D; B29D28/00; B29C; B29C48/00; B29C48/022; C; C08; C08L; C08L53/00; C08L53/02; B29C48/03; B29C48/07; B29C48/08; B29K; B29K2007/00; B29K2019/00; B29K2096/00; B29K2096/04; B29L; B29L2007/00
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
60 words
In a process for producing thermoplastic rubber film by extruding thermoplastic rubber into a thin film, the improvement which comprises employing as the thermoplastic rubber a mixture of thermoplastic rubber and sufficient amorphous polypropylene to improve the processability of said thermoplastic rubber as evidenced by the ability to achieve a draw ratio while extruding said mixture of at least 1.
Claim 2
Dependent Claim
60 words
In a process for producing thermoplastic rubber film by extruding thermoplastic rubber into a thin film, the improvement which comprises employing as the thermoplastic rubber a mixture of thermoplastic rubber and sufficient amorphous polypropylene to improve the processability of said thermoplastic rubber as evidenced by the ability to achieve a draw ratio while extruding said mixture of at least 1.
Claim 3
Dependent Claim
20 words
The process of claim 1 wherein said thermoplastic rubber is a radial block copolymer of styrene with isoprene or butadiene.
Claim 4
Dependent Claim
18 words
The process of claim 2 wherein the amorphous polypropylene contains less than about 20 weight percent isotactic polypropylene.
Claim 5
Dependent Claim
18 words
The process of claim 2 wherein the amorphous polypropylene contains less than about 10 weight percent isotactic polypropylene.
Claim 6
Dependent Claim
35 words
The process of claim 2 wherein the amorphous polypropylene is employed in an amount within the range of from about 10 to about 35 weight percent, based on weight of thermoplastic rubber plus amorphous polypropylene.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-11-05 | 1983-05-07 | 1983-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-11-05 | 1987-05-07 | 1987-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-11-05 | 1991-05-07 | 1991-11-06 | $7700.00 | Window Closed / Lapsed |