Patent US4748207A successfully refreshed from Google Patents.
US4748207A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polypropylene sheet
Assignee: Sumitomo Chemical Co Ltd
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Filing: 1985-07-09
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Granted: 1988-05-31
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Expires: 2005-07-09
Abstract
Abstract A crystalline polypropylene sheet is described, characterized by containing a polymer of a vinylcycloalkane having at least 6 carbon atoms in an amount of 0.05 wt ppm to 1 wt % (calculated as a vinylcycloalkane unit). This sheet is excellent in stiffness and transparency and is suitable for use in the production of various articles such as containers and trays.
Inventors
- 👤 Masahiro Kakugo
- 👤 Yoshiharu Fukui
- 👤 Kizuku Wakatsuki
- 👤 Hideaki Nishio
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 18:32
CPC Classifications
C; C08; C08L; C08L23/00; C08L23/02; C08L23/10; C08L23/12; C08L23/14; C08L23/142; C08F; C08F210/00; C08F210/04; C08F210/06; C08L23/18; C08L23/20; C08L2314/00; C08L2314/02
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
119 words
A crystalline polypropylene extrusion molded sheet obtained from a crystalline polypropylene composition containing a polymer of a vinylcycloalkane having at least 6 carbon atoms in an amount of 0.05 wt ppm to 1 wt% calculated as a vinylcycloalkane unit, wherein said composition is prepared by one of the following methods: (1) a vinylcycloalkane having at least 6 carbon atoms is polymerized in the presence of a Ziegler-Natta catalyst, and subsequently propylene is homopolymerized or copolymerized with other α-olefin; or (2) the polymer as obtained in (1) is mixed with a propylene homopolymer or a propylene/α-olefin copolymer; or (3) a polymer of a vinylcycloalkane having at least 6 carbon atoms as mixed with a propylene homopolymer or a propylene/α-olefin copolymer.
Claim 2
Dependent Claim
119 words
A crystalline polypropylene extrusion molded sheet obtained from a crystalline polypropylene composition containing a polymer of a vinylcycloalkane having at least 6 carbon atoms in an amount of 0.05 wt ppm to 1 wt% calculated as a vinylcycloalkane unit, wherein said composition is prepared by one of the following methods: (1) a vinylcycloalkane having at least 6 carbon atoms is polymerized in the presence of a Ziegler-Natta catalyst, and subsequently propylene is homopolymerized or copolymerized with other α-olefin; or (2) the polymer as obtained in (1) is mixed with a propylene homopolymer or a propylene/α-olefin copolymer; or (3) a polymer of a vinylcycloalkane having at least 6 carbon atoms as mixed with a propylene homopolymer or a propylene/α-olefin copolymer.
Claim 3
Dependent Claim
31 words
A crystalline polypropylene extrusion molded sheet as claimed in claim 1, wherein the amount of the polymer of the vinylcycloalkane is 0.5 to 5,000 wt ppm calculated as a vinylcycloalkane unit.
Claim 4
Dependent Claim
25 words
A crystalline polypropylene extrusion molded sheet as claimed in claim 1, wherein the vinylcycloalkane is selected from vinylcyclobutane, vinylcyclopentane, vinyl-3-methylcyclopentane, vinylcyclohexane, vinyl-2-methylcyclohexane, vinyl-3-methylcyclohexane, and vinylnorbornane.
Claim 5
Dependent Claim
18 words
A crystalline polypropylene extrusion molded sheet as claimed in claim 1, wherein the vinylcycloalkane is vinylcyclohexane or vinylnorbornane.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-05-31 | 1991-11-30 | 1992-05-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-05-31 | 1995-11-30 | 1996-05-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-05-31 | 1999-11-30 | 2000-05-31 | $7700.00 | Window Closed / Lapsed |