Patent US4368031A successfully refreshed from Google Patents.
US4600545A
Expired / Lapsed
US
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Process for the preparation of fibers from polymeric materials
Assignee: Montedison SpA
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Filing: 1979-03-19
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Granted: 1986-07-15
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Expires: 1999-03-19
Abstract
Abstract Polyolefin fibers, which are suited for at least partially substituting the cellulose fibers in the manufacture of paper, are produced by a process which consists in preparing in a pressure vessel a solution of a polyolefin at a temperature higher than the boiling temperature of the solvent under normal conditions, and under autogenous pressure or a pressure greater than the autogenous pressure, in ejecting said solution under the above stated conditions into a zone of lower pressure, in allowing the ejected solution to expand at least partially in said zone, and in then hitting the at least partially expanded solution with a jet of a high-speed fluid, which is at a temperature lower than that of the solution, and has an angled direction with respect to the direction of ejection of the solution.
Inventors
- 👤 Paolo Galli
- 👤 Paolo Parrini
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 03:46
CPC Classifications
D; D01; D01D; D01D5/00; D01D5/11; D21; D21H; D21H13/00; D21H13/10; D21H13/12; D21H13/14; D21H5/00; D21H5/12; D21H5/20; D21H5/202
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
191 words
A process for obtaining short, elongated fibers of a polyolefinic material which are useful as produced and without prior cutting thereof, or disintegrating operations, in the manufacture of paper by conventional paper-making methods, which comprises ejecting a homogeneous, one-phase solution of from 50 to 400 grams of a polyolefinic material per liter of a solvent thereof and which is free of liquids immiscible with the solvent at a temperature at least 60° C. higher than the boiling point of the solvent and under antogenous or higher than autogenous pressure, into a zone of lower pressure in which the solution at least partially expands; and hitting the at least partially expanded solution with a jet of fluid maintained at a temperature lower than the temperature of the solution, the angle at which the jet of fluid hits the at least partially expanded solution of polyolefinic material being between 30° and 90°, the speed at which the solution of polyolefinic material is ejected into the zone of lower pressure being from 1,000 to 200,000 meters per hour, and the impact speed of the hitting fluid being from 200 to 600 meters per second.
Claim 2
Dependent Claim
191 words
A process for obtaining short, elongated fibers of a polyolefinic material which are useful as produced and without prior cutting thereof, or disintegrating operations, in the manufacture of paper by conventional paper-making methods, which comprises ejecting a homogeneous, one-phase solution of from 50 to 400 grams of a polyolefinic material per liter of a solvent thereof and which is free of liquids immiscible with the solvent at a temperature at least 60° C. higher than the boiling point of the solvent and under antogenous or higher than autogenous pressure, into a zone of lower pressure in which the solution at least partially expands; and hitting the at least partially expanded solution with a jet of fluid maintained at a temperature lower than the temperature of the solution, the angle at which the jet of fluid hits the at least partially expanded solution of polyolefinic material being between 30° and 90°, the speed at which the solution of polyolefinic material is ejected into the zone of lower pressure being from 1,000 to 200,000 meters per hour, and the impact speed of the hitting fluid being from 200 to 600 meters per second.
Claim 3
Dependent Claim
33 words
The process according to claim 1, in which the speed at which the solution of polyolefinic material is ejected into the zone of lower pressure is from 1,500 to 50,000 meters per hour.
Claim 4
Dependent Claim
40 words
The process according to claim 1, in which the ratio of the hitting fluid speed to the speed at which the solution of polyolefinic material is ejected into the zone of lower pressure is from about 3.6 to about 2222.
Claim 5
Dependent Claim
41 words
The process according to claim 1, in which the ratio of the speed of the hitting fluid to the speed at which the solution of polyolefinic material is ejected into the zone of lower pressure is from about 14.4 to 1450.
Claim 6
Dependent Claim
27 words
The process according to claim 1, wherein the polyolefinic material is a polyethylene containing, in minor amounts, units of a monomer different from ethylene and copolymerizable therewith.
Claim 7
Dependent Claim
11 words
Process according to claim 1 wherein the polyolefinic material is polyethylene.
Claim 8
Dependent Claim
17 words
Process according to claim 1, wherein the polyolefinic material is a copolymer of at least two olefins.
Claim 9
Dependent Claim
20 words
Process according to claim 1, wherein the solution includes besides the polyolefinic material, at least one polymer containing polar groups.
Claim 10
Dependent Claim
13 words
Process according to claim 1, wherein the high-speed fluid jet consists of steam.
Claim 11
Dependent Claim
28 words
Process according to claim 9, wherein the angle comprised between the direction of the fluid and that of ejection of the solution, is comprised between 80° and 85°.
Claim 12
Dependent Claim
17 words
Process according to claim 1, wherein the high-speed fluid jet consists of carbon dioxide at room temperature.
Claim 13
Dependent Claim
28 words
Process according to claim 11, wherein the angle comprised between the direction of the fluid and that of ejection of the solution, is comprised between 80° and 85°.
Claim 14
Dependent Claim
16 words
Process according to claim 1, wherein the high-speed fluid jet consists of nitrogen at room temperature.
Claim 15
Dependent Claim
28 words
Process according to claim 13, wherein the angle comprised between the direction of the fluid and that of ejection of the solution, is comprised between 50° and 55°.
Claim 16
Dependent Claim
16 words
Process according to claim 1, wherein the high-speed fluid jet consists of oxygen at room temperature.
Claim 17
Dependent Claim
28 words
Process according to claim 15, wherein the angle comprised between the direction of the fluid and that of ejection of the solution, is comprised between 40° and 60°.
Claim 18
Dependent Claim
15 words
Process according to claim 1, wherein the zone of lower pressure is at atmospheric pressure.
Claim 19
Dependent Claim
12 words
Process according to claim 1, wherein the polyolefin solution contains a surfactant.
Claim 20
Dependent Claim
28 words
Process according to claim 1, wherein the high-speed fluid is used in the form of a mass which is geometrically co-axial with the nozzle ejecting the polyolefin solution.
Claim 21
Dependent Claim
10 words
Process according to claim 1 wherein the solvent is hexane.
Claim 22
Dependent Claim
10 words
Process according to claim 1, wherein the solvent is heptane.
Claim 23
Dependent Claim
10 words
Process according to claim 1, wherein the solvent is trichlorofluoromethane.
Claim 24
Dependent Claim
15 words
Process according to claim 1, wherein the polyolefin solution contains very finely subdivided inorganic materials.
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) | 1989-07-14 | 1990-01-13 | 1990-07-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-07-14 | 1994-01-13 | 1994-07-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-07-14 | 1998-01-13 | 1998-07-15 | $7700.00 | Window Closed / Lapsed |