Patent US3950293A successfully refreshed from Google Patents.
US3950293A
Expired / Lapsed
US
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Production of non-foaming aqueous suspensions of polyethylene or polypropylene fibrids
Assignee: BASF SE
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Filing: 1974-10-17
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Granted: 1976-04-13
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Expires: 1994-10-17
Abstract
Abstract Aqueous suspensions of polyolefin fibrids are prepared. To avoid foam formation and improve fiberbonding, small amounts of anionic agents are added to the suspensions. The suspensions are suitable for the manufacture of paper-like or textile-like web structures distinguished by very good fiber bonding and good initial wet strength.
Inventors
- 👤 Bruno Sander
- 👤 Eckhard Bonitz
- 👤 Heinz Berbner
- 👤 Manfred Hoffmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:50
CPC Classifications
D; D21; D21H; D21H5/00; D21H5/12; D21H5/1254; D21H13/00; D21H13/10; D21H13/12; D21H13/14; D21H17/00; D21H17/20; D21H17/33
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
87 words
A process for the manufacture of non-foaming aqueous suspensions of polyolefin fibrids by dispersing polyethylene fibrids or polypropylene fibrids in water in the presence of a dispersing agent, said fibrids having a specific surface area of 1-150 m 2 /g, the improvement wherein the dispersing agent used consists of from 0.1 to 2.0% by weight, based on the dry weight of the fibrids, of an ammonium salt of a copolymer of styrene and acrylic acid, said copolymer having a styrene to acrylic acid molar ratio of 1.6:1.
Claim 2
Dependent Claim
87 words
A process for the manufacture of non-foaming aqueous suspensions of polyolefin fibrids by dispersing polyethylene fibrids or polypropylene fibrids in water in the presence of a dispersing agent, said fibrids having a specific surface area of 1-150 m 2 /g, the improvement wherein the dispersing agent used consists of from 0.1 to 2.0% by weight, based on the dry weight of the fibrids, of an ammonium salt of a copolymer of styrene and acrylic acid, said copolymer having a styrene to acrylic acid molar ratio of 1.6:1.
Claim 3
Dependent Claim
24 words
A process as claimed in claim 1, said ammonium salt having a viscosity of a 20% aqueous solution thereof at 20°C. of 2,500 centipoise.
Claim 4
Dependent Claim
52 words
A process as claimed in claim 1 wherein said fibrids are polyethylene fibrids in which the polyethylene has a density between 0.915 and 0.965 g/cm 3 and a melt index of 0.01 to 100 g/10 min. as determined according to ASTM D 1238-65 T at 190°C under a load of 2.16 kg.
Claim 5
Dependent Claim
33 words
A process as claimed in claim 1 wherein said fibrids are polypropylene fibrids in which the polypropylene has an intrinsic viscosity of from 1.5 to 8 dl/g, as measured at 130°C in decalin.
References Cited (Backward Citations)
US3743570A
Cited
US3834983A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-04-13 | 1979-10-13 | 1980-04-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-04-13 | 1983-10-13 | 1984-04-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-04-13 | 1987-10-13 | 1988-04-13 | $7700.00 | Window Closed / Lapsed |