EP0056418A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Polyphenylene sulfide filament sheet and process for their production
Assignee: Toray Industries Inc
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Filing: 1981-06-24
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Granted: —
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Expires: 2001-06-24
Abstract
Abstract Sheets formed of randomly opened and laminated polyphenylene sulfide (PPS) filaments and process for their production. The PPS filament sheets can be obtained by directly combining the high-speed take-off step using an air stream with the sheet-making step, and are extremely useful as industrial filters, heat-insulating materials, electric materials, etc. utilizing their excellent chemical resistance, heat resistance, insulating properties, etc.
Inventors
- 👤 Shunsuke Fukata
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 17:41
CPC Classifications
D; D04; D04H; D04H3/00; D04H3/08; D04H3/12; Y; Y10; Y10T; Y10T428/00; Y10T428/26; Y10T428/269; Y10T428/27; Y10T428/29; Y10T428/2913; Y10T428/2922; Y10T428/298
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
23 words
A sheet of PPS filaments which comprises randomly dis- persed and accumulated PPS filaments, each having a fineness of 0.1 to 15 denier.
Claim 2
Dependent Claim
23 words
A sheet of PPS filaments which comprises randomly dis- persed and accumulated PPS filaments, each having a fineness of 0.1 to 15 denier.
Claim 3
Dependent Claim
34 words
2 . A sheet of PPS filaments as claimed in Claim 1, wherein said PPS filaments are made of a linear polymer more than 90 mol% of which is composed of p-phenylene sulfide units.
Claim 4
Dependent Claim
23 words
A sheet of PPS filaments as claimed in Claim 1, wherein said PPS filaments have a shrinkage of 5 to 40% at 140°C.
Claim 5
Dependent Claim
36 words
A sheet of PPS filaments as claimed in Claim 1, wherein said PPS filaments are bonded with at least one thermosetting resin selected from the group consisting of polyimide, polyamide-imide, aromatic polyamide, polybenzimidazole, and polyarylene sulfide.
Claim 6
Dependent Claim
29 words
A sheet of PPS filaments as claimed in Claim 5, wherein the quantity of said thermosetting resin is 5 to 90 wt% based on the quantity of the filaments.
Claim 7
Dependent Claim
17 words
A sheet of PPS filaments as claimed in Claim 1, wherein said filaments are felted by interlocking.
Claim 8
Dependent Claim
81 words
A process for producing a sheet of PPS filaments which comprises extruding a PPS polymer from a plurality of small holes at a temperature 20 to 85°C higher than the melting point of the PPS polymer, drawing apart the extrudate from the small holes at a rate greater than 1300 m/min by a high-velocity air stream, simultaneously causing the resulting filaments to be opened by electrostatic charge, collecting the opened filaments on a plane, and bonding or interlocking the collected filaments.
Claim 9
Dependent Claim
81 words
A process for producing a sheet of PPS filaments which comprises extruding a PPS polymer from a plurality of small holes at a temperature 20 to 85°C higher than the melting point of the PPS polymer, drawing apart the extrudate from the small holes at a rate greater than 1300 m/min by a high-velocity air stream, simultaneously causing the resulting filaments to be opened by electrostatic charge, collecting the opened filaments on a plane, and bonding or interlocking the collected filaments.
Claim 10
Dependent Claim
49 words
A process for producing a sheet of PPS filaments as claimed in Claim 7, wherein said PPS polymer is composed of more than 90 mol% of p-phenylene sulfide units and has "n" which is represented by 0.9 < n < 3.0 (where n is as defined in the specification).
Claim 11
Dependent Claim
29 words
A process for producing a sheet of PPS filaments as claimed in Claim 8, wherein said PPS polymer has "n" which is represented by 0.9 < n < 2.0.
Claim 12
Dependent Claim
37 words
A process for producing a sheet of PPS filaments as claimed in Claim 7, wherein said PPS polymer has a melt viscosity of 300 to 100,000 poise at a shear rate of 200 sec -1 at 300°C.
Claim 13
Dependent Claim
36 words
A process for producing a sheet of PPS filaments as claimed in Claim 7, wherein the extrudate is drawn apart from the small holes at a rate greater than 1300 m/min by a high-velocity air stream.
Claim 14
Dependent Claim
31 words
A process for producing a sheet of PPS filaments as claimed in Claim 7, wherein the extrusion temperature is 30 to 60°C higher than the melting point of the PPS polymer.
Claim 15
Dependent Claim
22 words
A process for producing a sheet of PPS filaments as claimed in Claim 7, wherein the interlocking is performed by needle punching.
Claim 16
Dependent Claim
22 words
A process for producing a sheet of PPS filaments as claimed in Claim 7, wherein the interlocking is performed by water jet.
Claim 17
Dependent Claim
30 words
A process for producing a sheet of PPS filaments as claimed in Claim 7, wherein a heat bonding process and a compacting process using a hot calendering machine are added.
References Cited (Backward Citations)
No citation records indexed.
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