Patent US4634740A successfully refreshed from Google Patents.
US4634740A
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Polypropylene composition
Assignee: Tonen General Sekiyu KK
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Filing: 1985-04-08
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Granted: 1987-01-06
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Expires: 2005-04-08
Abstract
Abstract A polypropylene composition having superior clarity and good low-temperature impact resistance, said composition comprising 65 wt % to 95 wt % crystalline polypropylene and 5 wt % to 35 wt % of ethylene-propylene random copolymer containing higher than 70 wt % to 85 wt % of ethylene.
Inventors
- 👤 Yuji Fujita
- 👤 Tadao Ikeda
- 👤 Tokuo Makishima, deceased
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:41
CPC Classifications
C; C08; C08F; C08F210/00; C08F210/16; C08L; C08L23/00; C08L23/02; C08L23/10; C08L23/12; C08F110/00; C08F110/04; C08F110/06; C08L23/16
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
65 words
A polypropylene composition which comprises 65 wt% to 95 wt% crystalline polypropylene and 5 wt% to 35 wt% of an ethylene-propylene random copolymer containing higher than 70 wt% to 85 wt% ethylene wherein said ethylene-propylene random copolymer is produced by copolymerizing ethylene with propylene in the presence of a polymerization catalyst comprising a titanium trichloride containing catalyst component, an organoaluminum cocatalyst and a Lewis base.
Claim 2
Dependent Claim
65 words
A polypropylene composition which comprises 65 wt% to 95 wt% crystalline polypropylene and 5 wt% to 35 wt% of an ethylene-propylene random copolymer containing higher than 70 wt% to 85 wt% ethylene wherein said ethylene-propylene random copolymer is produced by copolymerizing ethylene with propylene in the presence of a polymerization catalyst comprising a titanium trichloride containing catalyst component, an organoaluminum cocatalyst and a Lewis base.
Claim 3
Dependent Claim
22 words
The polypropylene composition of claim 2 wherein the Lewis base is selected from a carboxylic acid ester, an ether or a ketone.
Claim 4
Dependent Claim
17 words
The polypropylene composition of claim 2 wherein the catalyst comprises titanium trichloride, diethylaluminum chloride, and ethyl p-anisate.
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) | 1990-01-05 | 1990-07-07 | 1991-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-01-05 | 1994-07-07 | 1995-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-01-05 | 1998-07-07 | 1999-01-06 | $7700.00 | Window Closed / Lapsed |