US4526735A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing fibrous assembly
Assignee: Teijin Ltd
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Filing: 1983-02-09
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Granted: 1985-07-02
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Expires: 2003-02-09
Abstract
Abstract A process and apparatus for producing a fibrous assembly. At least one fiber-forming polymer is extruded through a spinneret having numerous small openings. The process uses a die equipped with a spinneret having numerous closely spaced small openings and an opening ratio (α) of at least 30%. At least one fiber-forming polymer in the form of a shaped mass having a specified compression resistance is continuously stuffed into said die. Said shaped mass has a shape such that it measures more in one direction than in another. There is passed through the spinneret an electric current sufficient to give said fiber-forming polymer Joule heat required for cutting said polymer by partitioning members defining the numerous small openings of the spinneret. The cut fiber-forming polymer is taken up as fine streams. The present invention provides ultrathick aromatic polyamide fibers having an average cross-sectional area of about 0.01 mm 2 to about 5 mm 2 and comprising at least one fiber-forming aromatic polyamide and an inorganic or metallic fine powder or a fibrous material.
Inventors
- 👤 Susumu Norota
- 👤 Yasuhiko Segawa
- 👤 Tsutomu Kiriyama
- 👤 Shingo Emi
- 👤 Tadasi Imoto
- 👤 Tetsuo Yamauchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 15:29
CPC Classifications
D; D01; D01F; D01F6/00; D01F6/58; D01F6/60; D01F6/605; B; B29; B29C; B29C48/00; B29C48/03; B29C48/05; B29C48/07; B29C48/08; B29C48/25; B29C48/78; B29C48/86; B29C48/865; B29C48/88; B29C48/90; B29C48/908; D01D; D01D13/00; D01D4/00; D01D4/02; D01D5/00; D01D5/08; D01F1/00; D01F1/02; B29C48/06; Y; Y10; Y10S; Y10S264/00; Y10S264/46
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
218 words
A process for producing a fibrous assembly by extruding at least one fiber-forming polymer through a spinneret having numerous small openings, said process comprising using a die equipped with a spinneret having numerous closely spaced small openings having an opening ratio (α), defined by the following equation, of at least 30%, ##EQU9## wherein V a (cm 3 ) is the total apparent volume of the spinneret which is taken within 1 cm 2 of the porous portion of the spinneret and V f (cm 3 ) is the total volume of partitioning members defining the small openings which is taken within 1 cm 2 of the porous portion of the spinneret; continuously stuffing at least one fiber-forming polymer in the form of a shaped mass into said die, said shaped mass having compression resistance such that at least in the initial stage of its stuffing into the die, it substantially retains its form in resistance to the stuffing pressure, and said shaped mass having such a shape that it measures more in one direction than in another; passing through the spinneret an electric current sufficient to give said fiber-forming polymer Joule heat required for cutting said polymer by partitioning members defining the numerous small openings of the spinneret; and taking up the cut fiber-forming polymer as fine streams.
Claim 2
Dependent Claim
218 words
A process for producing a fibrous assembly by extruding at least one fiber-forming polymer through a spinneret having numerous small openings, said process comprising using a die equipped with a spinneret having numerous closely spaced small openings having an opening ratio (α), defined by the following equation, of at least 30%, ##EQU9## wherein V a (cm 3 ) is the total apparent volume of the spinneret which is taken within 1 cm 2 of the porous portion of the spinneret and V f (cm 3 ) is the total volume of partitioning members defining the small openings which is taken within 1 cm 2 of the porous portion of the spinneret; continuously stuffing at least one fiber-forming polymer in the form of a shaped mass into said die, said shaped mass having compression resistance such that at least in the initial stage of its stuffing into the die, it substantially retains its form in resistance to the stuffing pressure, and said shaped mass having such a shape that it measures more in one direction than in another; passing through the spinneret an electric current sufficient to give said fiber-forming polymer Joule heat required for cutting said polymer by partitioning members defining the numerous small openings of the spinneret; and taking up the cut fiber-forming polymer as fine streams.
Claim 3
Dependent Claim
19 words
The process of claim 1 wherein the spinneret has an opening ratio (α) of about 40 to about 95%.
Claim 4
Dependent Claim
26 words
The process of claim 1 wherein the number of the small openings per cm 2 of the extrusion surface of the spinneret is at least one.
Claim 5
Dependent Claim
28 words
The process of claim 3 wherein the number of the small openings per cm 2 of the extrusion surface of the spinneret is about 5 to about 1,000.
Claim 6
Dependent Claim
18 words
The process of claim 1 wherein the spinneret has a thickness of not more than about 10 mm.
Claim 7
Dependent Claim
25 words
The process of claim 1 wherein the amount of electric current passed is about 0.5 to about 5,000 watts per cm 2 of the spinneret.
Claim 8
Dependent Claim
30 words
The process of claim 1 wherein in a passage within the die which leads to the spinneret, the fiber-forming polymer is pre-heated gradually to a higher temperature toward the spinneret.
Claim 9
Dependent Claim
23 words
The process of claim 1 wherein the shaped mass of the fiber-forming polymer is a compression-molded mass of the polymer in powder form.
Claim 10
Dependent Claim
22 words
The process of claim 8 wherein the compression-molded article has an apparent density which is 0.3 to 0.95 times its true density.
Claim 11
Dependent Claim
20 words
The process of claim 1 wherein the shaped mass of the fiber-forming polymer is a melt-molded mass of the polymer.
Claim 12
Dependent Claim
17 words
The process of claim 1 wherein the shaped mass is in the shape of a flat plate.
Claim 13
Dependent Claim
16 words
The process of claim 1 wherein the shaped mass is in the shape of a rod.
Claim 14
Dependent Claim
14 words
The process of claim 1 wherein the shaped mass is a laminate of films.
Claim 15
Dependent Claim
33 words
The process of claim 1 wherein the shaped mass contains an additive capable of passing through each of the small openings of the spinneret in addition to said at least one fiber-forming polymer.
Claim 16
Dependent Claim
21 words
The process of claim 1 wherein the shaped mass has a compression strength of at least about 1 kg/cm 2 .
Claim 17
Dependent Claim
26 words
The process of claim 1 wherein the amount of the fiber-forming polymer extruded is about 0.1 to about 20 g/min. per cm 2 of the spinneret.
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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) | 1988-07-01 | 1988-12-31 | 1989-07-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-01 | 1992-12-31 | 1993-07-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-01 | 1996-12-31 | 1997-07-02 | $7700.00 | Window Closed / Lapsed |