Patent US4500706A successfully refreshed from Google Patents.
US4500706A
Expired / Lapsed
US
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Method of producing extrusion grade poly(arylene sulfide)
Assignee: Phillips Petroleum Co
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Filing: 1982-08-09
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Granted: 1985-02-19
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Expires: 2002-08-09
Abstract
Abstract A method of producing poly(arylene sulfide) resin suitable for the commercial production of fibers. The method includes the two stage melt filtration of a suitable poly(arylene sulfide) polymer, e.g., poly(p-phenylene sulfide), through a primary filter having an absolute micron rating of no more than about 125 microns, and through a secondary filter having a maximum absolute micron rating of about 80 or a substantially equivalent filter capacity. Also disclosed are various forms of apparatus for performing the method. In one form the apparatus employs a depth type filter of metallurgically bonded micronic size stainless steel fibers as the primary filter and one or more edge sealed screen combinations each containing one 325 mesh screen as the secondary filter. A secondary filter comprising a mesh screen and a quantity of suitable sand is also disclosed.
Inventors
- 👤 Ronald D. Mathis
- 👤 Jerry O. Reed
- 👤 Gerald E. Hagler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 19:01
CPC Classifications
D; D01; D01F; D01F6/00; D01F6/58; D01F6/76; D01F6/765; D01D; D01D1/00; D01D1/10; D01D1/106
Claims Analysis
Total Claims: 67
Claim 1
Independent Claim
89 words
A method of processing a polymer comprising poly(arylene sulfide), comprising the steps of: forcing molten polymer comprising poly(arylene sulfide) through primary filter means comprising a depth type filter comprising metallurgically bonded metal fibers and having an absolute micron rating in the range from about 45 to about 125 to provide molten primary filtered polymer; and forcing said molten primary filtered polymer through secondary filter means having a maximum absolute micron rating of no more than about 80 or a substantially equivalent filtration capability to provide molten secondary filtered polymer.
Claim 2
Independent Claim
89 words
A method of processing a polymer comprising poly(arylene sulfide), comprising the steps of: forcing molten polymer comprising poly(arylene sulfide) through primary filter means comprising a depth type filter comprising metallurgically bonded metal fibers and having an absolute micron rating in the range from about 45 to about 125 to provide molten primary filtered polymer; and forcing said molten primary filtered polymer through secondary filter means having a maximum absolute micron rating of no more than about 80 or a substantially equivalent filtration capability to provide molten secondary filtered polymer.
Claim 3
Dependent Claim
24 words
A method in accordance with claim 1 wherein the maximum absolute micron rating of said primary filter means is no more than about 100.
Claim 4
Dependent Claim
19 words
A method in accordance with claim 2 wherein said secondary filter means comprises a plurality of superposed mesh screens.
Claim 5
Dependent Claim
17 words
A method in accordance with claim 2 wherein said secondary filter means comprises three superposed mesh screens.
Claim 6
Dependent Claim
18 words
A method in accordance with claim 4 wherein said mesh screens are U.S. Standard Sieve 325 mesh screens.
Claim 7
Dependent Claim
31 words
A method in accordance with claim 1 wherein said secondary filter means comprises three superposed screens each having an absolute micron rating in the range from about 59 to about 73.
Claim 8
Dependent Claim
23 words
A method in accordance with claim 1 wherein said secondary filter means comprises at least one mesh screen and a quantity of sand.
Claim 9
Dependent Claim
32 words
A method in accordance with claim 1 wherein said secondary filter means comprises a plurality of superposed metal mesh screens each having an absolute micron rating from about 59 to about 73.
Claim 10
Dependent Claim
13 words
A method in accordance with claim 8 wherein said polymer comprises poly(phenylene sulfide).
Claim 11
Dependent Claim
26 words
A method in accordance with claim 8 wherein said poly(arylene sulfide) is characterized further as having a concentration of 1-chloronapthalene insolubles of at least 40 ppm.
Claim 12
Dependent Claim
31 words
A method in accordance with claim 9 wherein said poly(phenylene sulfide) is characterized further as having a concentration of 1-chloronapthalene insolubles in the range from about 50 to about 300 ppm.
Claim 13
Dependent Claim
31 words
A method in accordance with claim 8 wherein said poly(arylene sulfide) is characterized further as having a melt flow rate in the range from about 50 to about 600 g/10 min.
Claim 14
Dependent Claim
31 words
A method in accordance with claim 9 wherein said poly(phenylene sulfide) is characterized further as having a melt flow rate in the range from about 150 to about 400 g/10 min.
Claim 15
Dependent Claim
23 words
A method in accordance with claim 10 characterized further to include the step of extruding the secondary filtered polymer into an extruded product.
Claim 16
Dependent Claim
13 words
A method in accordance with claim 14 wherein said polymer comprises poly(phenylene sulfide).
Claim 17
Dependent Claim
26 words
A method in accordance with claim 14 wherein said poly(arylene sulfide) is characterized further as having a concentration of 1-chloronapthalene insolubles of at least 40 ppm.
Claim 18
Dependent Claim
31 words
A method in accordance with claim 15 wherein said poly(phenylene sulfide) is characterized further as having a concentration of 1-chloronapthalene insolubles in the range from about 50 to about 300 ppm.
Claim 19
Dependent Claim
31 words
A method in accordance with claim 16 wherein said poly(arylene sulfide) is characterized further as having a melt flow rate in the range from about 50 to about 600 g/10 min.
Claim 20
Dependent Claim
31 words
A method in accordance with claim 17 wherein said poly(phenylene sulfide) is characterized further as having a melt flow rate in the range from about 150 to about 400 g/10 min.
Claim 21
Dependent Claim
13 words
A method in accordance with claim 1 wherein said polymer comprises poly(phenylene sulfide).
Claim 22
Dependent Claim
31 words
A method in accordance with claim 20 wherein said poly(phenylene sulfide) is characterized further as having a concentration of 1-chloronapthalene insolubles in the range from about 50 to about 300 ppm.
Claim 23
Dependent Claim
31 words
A method in accordance with claim 20 wherein said poly(phenylene sulfide) is characterized further as having a melt flow rate in the range from about 150 to about 400 g/10 min.
Claim 24
Dependent Claim
25 words
A method in accordance with claim 1 wherein said poly(arylene sulfide) is characterized further as having a concentration of 1-chloronapthalene insolubles of at 40 ppm.
Claim 25
Dependent Claim
31 words
A method in accordance with claim 1 wherein said poly(arylene sulfide) is characterized further as having a melt flow rate in the range from about 50 to about 600 g/10 min.
Claim 26
Independent Claim
98 words
A method of processing a normally solid thermoplastic material for melt spinning into fibers comprising the steps of: passing molten poly(arylene sulfide) through primary filter means comprising depth type filter media comprising metallurgically bonded metal fibers and having an absolute micron rating in the range from about 45 to about 125 to provide molten primary filtered polymer; and passing said molten primary filtered polymer through secondary filter means having an absolute micron rating less than or a substantially equivalent filtration capacity greater than the absolute micron rating or the substantially equivalent filtration capacity of said primary filter means.
Claim 27
Independent Claim
98 words
A method of processing a normally solid thermoplastic material for melt spinning into fibers comprising the steps of: passing molten poly(arylene sulfide) through primary filter means comprising depth type filter media comprising metallurgically bonded metal fibers and having an absolute micron rating in the range from about 45 to about 125 to provide molten primary filtered polymer; and passing said molten primary filtered polymer through secondary filter means having an absolute micron rating less than or a substantially equivalent filtration capacity greater than the absolute micron rating or the substantially equivalent filtration capacity of said primary filter means.
Claim 28
Dependent Claim
22 words
A method in accordance with claim 25 wherein said secondary filter means comprises at least one U.S. Standard Sieve 325 mesh screen.
Claim 29
Dependent Claim
21 words
A method in accordance with claim 25 wherein said secondary filter means comprises three superposed U.S. Standard Sieve 325 mesh screens.
Claim 30
Dependent Claim
25 words
A method in accordance with claim 25 wherein said secondary filter means comprises one U.S. Standard Sieve 325 mesh screen and a quantity of sand.
Claim 31
Dependent Claim
17 words
A method in accordance with claim 28 wherein said sand is 20/40 U.S. Standard Sieve mesh sand.
Claim 32
Dependent Claim
17 words
A method in accordance with claim 28 wherein said sand is 60/80 U.S. Standard Sieve mesh sand.
Claim 33
Dependent Claim
15 words
A method in accordance with claim 25 wherein said molten poly(arylene sulfide) comprises poly(phenylene sulfide).
Claim 34
Dependent Claim
26 words
A method in accordance with claim 31 wherein said poly(phenylene sulfide) is characterized further as having a concentration of 1-chloronapthalene insolubles of at least 40 ppm.
Claim 35
Dependent Claim
31 words
A method in accordance with claim 31 wherein said poly(phenylene sulfide) is characterized further as having a melt flow rate in the range from about 50 to about 600 g/10 min.
Claim 36
Dependent Claim
22 words
A method in accordance with claim 25 wherein said poly(arylene sulfide) has a concentration of 1-chloronapthalene insolubles of at least 40 ppm.
Claim 37
Dependent Claim
26 words
A method in accordance with claim 25 wherein said poly(arylene sulfide) has melt flow rate in the range from about 50 to about 600 g/10 min.
Claim 38
Independent Claim
125 words
A method of processing a polymer comprising poly(arylene sulfide), comprising the steps of: forcing molten polymer comprising poly(arylene sulfide) through primary filter means comprising depth type filter media of metallurgically bonded metal fibers having an absolute micron rating in the range from about 45 to about 125 to provide a first quantity of molten primary filtered polymer; forming said molten primary filtered polymer into a plurality of primary filtered polymer pellets; melting said primary filtered polymer pellets to provide a second quantity of molten primary filtered polymer; and forcing said second quantity of molten primary filtered polymer through second filter means having a maximum absolute micron rating of no more than about 80 or a substantially equivalent filtration capacity to provide molten secondary filtered polymer.
Claim 39
Independent Claim
125 words
A method of processing a polymer comprising poly(arylene sulfide), comprising the steps of: forcing molten polymer comprising poly(arylene sulfide) through primary filter means comprising depth type filter media of metallurgically bonded metal fibers having an absolute micron rating in the range from about 45 to about 125 to provide a first quantity of molten primary filtered polymer; forming said molten primary filtered polymer into a plurality of primary filtered polymer pellets; melting said primary filtered polymer pellets to provide a second quantity of molten primary filtered polymer; and forcing said second quantity of molten primary filtered polymer through second filter means having a maximum absolute micron rating of no more than about 80 or a substantially equivalent filtration capacity to provide molten secondary filtered polymer.
Claim 40
Dependent Claim
24 words
A method in accordance with claim 36 characterized further to include the step of extruding the secondary filtered polymer into an extruded polymer product.
Claim 41
Dependent Claim
28 words
A method in accordance with claim 36 or claim 37 wherein said molten polymer comprises poly(phenylene sulfide) having a concentration of 1-chloronapthalene insolubles of at least 40 ppm.
Claim 42
Dependent Claim
28 words
A method in accordance with claim 36 or claim 37 wherein said molten polymer comprises poly(arylene sulfide) having a concentration of 1-chloronapthalene insolubles of at least 40 ppm.
Claim 43
Dependent Claim
33 words
A method in accordance with claim 36 or claim 37 wherein said molten polymer comprises poly(arylene sulfide) having a melt flow rate in the range from about 50 to about 600 g/10 min.
Claim 44
Independent Claim
109 words
A method of forming fibers from a polymer comprising poly(arylene sulfide) which has previously been subjected to primary filtration through primary filter means comprising a depth type filter of metallurgically bonded metal fibers having an absolute micron rating in the range from about 45 to about 125 to form a primary filtered polymer, comprising: melting the primary filtered pellets to provide molten primary filtered polymer and passing said molten primary filtered polymer through secondary filter means having a maximum absolute micron rating of no more than about 80 or a substantially equivalent filtration capacity to provide molten secondary filtered polymer; and thereafter forming fibers from said secondary filtered polymer.
Claim 45
Independent Claim
109 words
A method of forming fibers from a polymer comprising poly(arylene sulfide) which has previously been subjected to primary filtration through primary filter means comprising a depth type filter of metallurgically bonded metal fibers having an absolute micron rating in the range from about 45 to about 125 to form a primary filtered polymer, comprising: melting the primary filtered pellets to provide molten primary filtered polymer and passing said molten primary filtered polymer through secondary filter means having a maximum absolute micron rating of no more than about 80 or a substantially equivalent filtration capacity to provide molten secondary filtered polymer; and thereafter forming fibers from said secondary filtered polymer.
Claim 46
Dependent Claim
29 words
A method in accordance with claim 41 wherein the polymer has a concentration of 1-chloronapthalene insolubles of at least 40 ppm prior to passage through said primary filter means.
Claim 47
Dependent Claim
37 words
A method in accordance with claim 41 wherein the polymer comprises poly(phenylene sulfide) having a concentration of 1-chloronapthalene insolubles in the range from about 50 to about 300 ppm prior to passage through said primary filter means.
Claim 48
Dependent Claim
34 words
A method in accordance with claim 41 wherein the polymer has a melt flow rate in the range from about 50 to about 600 g/10 min prior to passage through said primary filter means.
Claim 49
Dependent Claim
19 words
A method in accordance with claim 41 wherein said secondary filter means comprises a plurality of superposed mesh screens.
Claim 50
Dependent Claim
32 words
A method in accordance with claim 41 wherein said secondary filter means comprises three superposed mesh screens each having an absolute micron rating in the range from about 59 to about 73.
Claim 51
Dependent Claim
26 words
A method in accordance with claim 41 or claim 25 wherein said secondary filter means comprises at least one mesh screen and a quantity of sand.
Claim 52
Dependent Claim
19 words
A method in accordance with claim 47 wherein said quantity of said is 20/40 U.S. Standard Sieve mesh sand.
Claim 53
Dependent Claim
19 words
A method in accordance with claim 47 wherein said quantity of sand is 60/80 U.S. Standard Sieve mesh sand.
Claim 54
Dependent Claim
21 words
A method in accordance with claim 41 wherein said secondary filter means comprises three superposed U.S. Standard Sieve 325 mesh screens.
Claim 55
Independent Claim
81 words
A method of processing a polymer comprising poly(arylene sulfide), comprising the steps of: passing molten polymer comprising poly(arylene sulfide) through primary filter means comprising a depth type filter comprising metallurgically bonded metal fibers and having an absolute micron rating in the range from about 45 to about 125 to provide molten primary filtered polymer; and passing said molten primary filtered polymer through secondary filter means to remove impurities which pass through said primary filter means and provide molten secondary filtered polymer.
Claim 56
Independent Claim
81 words
A method of processing a polymer comprising poly(arylene sulfide), comprising the steps of: passing molten polymer comprising poly(arylene sulfide) through primary filter means comprising a depth type filter comprising metallurgically bonded metal fibers and having an absolute micron rating in the range from about 45 to about 125 to provide molten primary filtered polymer; and passing said molten primary filtered polymer through secondary filter means to remove impurities which pass through said primary filter means and provide molten secondary filtered polymer.
Claim 57
Dependent Claim
25 words
A method in accordance with claim 51 wherein said polymer is characterized further as having a concentration of 1-chloronapthalene insolubles of at least 40 ppm.
Claim 58
Dependent Claim
30 words
A method in accordance with claim 51 wherein said polymer is characterized further as having a melt flow rate in the range from about 50 to about 600 g/10 min.
Claim 59
Dependent Claim
37 words
A method in accordance with claim 47 wherein said quantity of sand has a depth sufficient to provide effective filtration of polymer passing therethrough without exceeding an initial pressure of 3000 psig at said second filter means.
Claim 60
Dependent Claim
21 words
A method in accordance with claim 47 wherein said quantity of sand has a depth of at least about 1/4 inch.
Claim 61
Dependent Claim
38 words
A method in accordance with claim 47 wherein said quantity of sand consists of particles which will pass through a 16 U.S. Standard Sieve mesh screen and will not pass through a 100 U.S. Standard Sieve mesh screen.
Claim 62
Dependent Claim
40 words
A method in accordance with claim 7 or claim 28 wherein said quantity of sand has a depth sufficient to provide effective filtration of polymer passing therethrough without exceeding an initial pressure of 3000 psig at said second filter means.
Claim 63
Dependent Claim
24 words
A method in accordance with claim 7 or claim 28 wherein said quantity of sand has a depth of at least about 1/4 inch.
Claim 64
Dependent Claim
41 words
A method in accordance with claim 7 or claim 28 wherein said quantity of sand consists of particles which will pass through a 16 U.S. Standard Sieve mesh screen and will not pass through a 100 U.S. Standard Sieve mesh screen.
Claim 65
Dependent Claim
75 words
A method in accordance with claim 1 comprising the additional step of: forcing molten polymer comprising poly(arylene sulfide) through filter means having a maximum absolute micron rating greater than the absolute micron rating of said primary filter means prior to said step of forcing molten polymer comprising poly(arylene sulfide) through said primary filter means to provide said polymer comprising poly(arylene sulfide) to said step of forcing molten polymer comprising poly(arylene sulfide) through primary filter means.
Claim 66
Dependent Claim
56 words
A method in accordance with claim 25 characterized further to include: passing molten poly(arylene sulfide) through a relatively coarse filter means having an absolute micron rating greater than the absolute micron rating of said primary filter means to provide relatively coarse filtered poly(arylene sulfide) to the step of passing molten poly(arylene sulfide) through primary filter means.
Claim 67
Dependent Claim
51 words
A method in accordance with claim 51 characterized further to include: passing molten polymer comprising poly(arylene sulfide) through relatively coarse filter means having an absolute micron rating greater than the absolute micron rating of said primary filter means to provide relatively coarse filtered polymer comprising poly(arylene sulfide) through primary filter means.
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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) | 1988-02-19 | 1988-08-20 | 1989-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-19 | 1992-08-20 | 1993-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-19 | 1996-08-20 | 1997-02-19 | $7700.00 | Window Closed / Lapsed |