Patent US3985933A successfully refreshed from Google Patents.
US3985933A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fibers
Assignee: Shell USA Inc
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Filing: 1974-12-06
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Granted: 1976-10-12
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Expires: 1994-12-06
Abstract
Abstract Improved fibrillated fibers made by fibrillating an oriented film or sheet, where the film or sheet is from about 70 to about 99.5 weight percent of polypropylene and from about 30 to about 0.5 weight percent of a rubber selected from the group consisting of polybutadiene or polystyrene/polybutadiene block copolymer.
Inventors
- 👤 Hemant Mehta
- 👤 Willy H. J. Badrian
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 15:28
CPC Classifications
D; D01; D01D; D01D5/00; D01D5/42; D01D5/423; Y; Y10; Y10S; Y10S264/00; Y10S264/47; Y10S428/00; Y10S428/91; Y10T; Y10T428/00; Y10T428/29
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
136 words
Improved fibrillated polypropylene fibers from film, having better hand, gloss, resilience, dyeability and denier control, comprising fibers made by fibrillating an oriented film of no more than about 1 mil thickness, made by heat stretching at an elevated temperature but below its melting point a film comprised of from about 70 to about 99.5 weight percent polypropylene and from about 30 to about 0.5 weight percent of a rubber selected from the group consisting of polybutadiene and polybutadiene/polystyrene block copolymer where said polybutadiene has a cis 1,4 content of at least about 90 percent and said polybutadiene/polystyrene block copolymer has a polystyrene content of from about 50 to about 10 weight percent and the polybutadiene block has a cis 1-4 content of at least about 35 percent and 1-2 content of less than about 20 percent.
Claim 2
Dependent Claim
136 words
Improved fibrillated polypropylene fibers from film, having better hand, gloss, resilience, dyeability and denier control, comprising fibers made by fibrillating an oriented film of no more than about 1 mil thickness, made by heat stretching at an elevated temperature but below its melting point a film comprised of from about 70 to about 99.5 weight percent polypropylene and from about 30 to about 0.5 weight percent of a rubber selected from the group consisting of polybutadiene and polybutadiene/polystyrene block copolymer where said polybutadiene has a cis 1,4 content of at least about 90 percent and said polybutadiene/polystyrene block copolymer has a polystyrene content of from about 50 to about 10 weight percent and the polybutadiene block has a cis 1-4 content of at least about 35 percent and 1-2 content of less than about 20 percent.
Claim 3
Dependent Claim
21 words
The improved fibers of claim 1 where the rubber content ranges from about 20 weight percent to about 2 weight percent.
Claim 4
Dependent Claim
21 words
The improved fibers of claim 1 where the rubber content ranges from about 10 weight percent to about 5 weight percent.
Claim 5
Dependent Claim
16 words
The improved fibers of claim 3 having a denier within the range of 5-10 grams/9000 meters.
Claim 6
Dependent Claim
145 words
A process for the formation of fibers which consists of: a. forming a film comprised of about 70 to about 99.5 weight percent polypropylene and about 30 to about 0.5 weight percent of a rubber selected from the group consisting of polybutadiene and polybutadiene/polystyrene block copolymers said polybutadiene having a cis 1-4 content of at least 90 percent and said polybutadiene/polystyrene block copolymer having a polystyrene content ranging from about 50 percent to about 10 percent and a polybutadiene block having a cis 1-4 content of at least about 35 percent and a 1-2 content of less than about 20 percent, b. orienting said film by stretching it while it is at an elevated temperature but below its melting point to form an oriented film of no more than about 1 mil thickness and subjecting the oriented film to fibrillation conditions to form the fibers.
Claim 7
Dependent Claim
145 words
A process for the formation of fibers which consists of: a. forming a film comprised of about 70 to about 99.5 weight percent polypropylene and about 30 to about 0.5 weight percent of a rubber selected from the group consisting of polybutadiene and polybutadiene/polystyrene block copolymers said polybutadiene having a cis 1-4 content of at least 90 percent and said polybutadiene/polystyrene block copolymer having a polystyrene content ranging from about 50 percent to about 10 percent and a polybutadiene block having a cis 1-4 content of at least about 35 percent and a 1-2 content of less than about 20 percent, b. orienting said film by stretching it while it is at an elevated temperature but below its melting point to form an oriented film of no more than about 1 mil thickness and subjecting the oriented film to fibrillation conditions to form the fibers.
Claim 8
Dependent Claim
22 words
The process of claim 5 where the rubber content of the film is from about 20 weight percent to about 2 percent.
Claim 9
Dependent Claim
23 words
The process of claim 5 where the rubber content of the film is from about 10 weight percent to about 5 weight percent.
Claim 10
Dependent Claim
13 words
The fibers of claim 1 where the rubber is a polybutadiene/polystyrene block copolymer.
Claim 11
Dependent Claim
20 words
The fibers of claim 8 where the copolymer content ranges from about 10 weight percent to about 5 weight percent.
Claim 12
Dependent Claim
13 words
The process of claim 5 where the rubber is a polybutadiene/polystyrene block copolymer.
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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) | 1979-10-12 | 1980-04-12 | 1980-10-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-10-12 | 1984-04-12 | 1984-10-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-10-12 | 1988-04-12 | 1988-10-12 | $7700.00 | Window Closed / Lapsed |