Patent US3482783A successfully refreshed from Google Patents.
Patent US4123490A successfully refreshed from Google Patents.
US4123490A
Expired / Lapsed
US
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Production of a high tenacity, low denier poly(ethylene terephthalate) fibrillated tape yarn
Assignee: Celanese Corp
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Filing: 1975-11-20
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Granted: 1978-10-31
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Expires: 1995-11-20
Abstract
Abstract A low denier, high tenacity poly(ethylene terephthalate) fibrillated tape yarn particularly suited for conversion into a sewing thread which exhibits excellent sewing performance is produced by intimately mixing poly(ethylene terephthalate) polymer with from about 0.1 to 20 percent polypropylene based on the weight of poly(ethylene terephthalate), extruding the polymer mixture in the form of a tape through a slit die having a modified entry port wherein the depth of the slit is greater at both ends than at the middle, at a melt draw down of from about 26:1 to about 75:1, quenching said tape, hot drawing said tape in two stages wherein said tape is initially hot drawn to a draw ratio of from about 3.3 to about 4.2 while being subjected to a temperature of from about 80° to about 140° centigrade, thereafter hot drawing to a total draw ratio of about 5.0 while heated to a temperature about 160° and thereafter subjecting the tape to fibrillation. A slit die with a modified entry port which allows extrusion of a low denier tape at high draw down ratios is also disclosed.
Inventors
- 👤 John D. Gibbon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:59
CPC Classifications
D; D01; D01D; D01D5/00; D01D5/42; B; B29; B29C; B29C48/00; B29C48/03; B29C48/07; B29C48/08; B29C48/25; B29C48/30; B29C48/305; B29C48/001; B29C48/0012; B29C48/0018; B29K; B29K2105/00; B29K2105/04; Y; Y10; Y10S; Y10S264/00; Y10S264/47
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
165 words
A method of producing a low denier, high tenacity relatively uniformly fibrillatable poly(ethylene terephthalate) tape comprising a. intimately mixing poly(ethylene terephthalate) polymer with from about 0.1 to about 20 percent based on the weight of poly(ethylene terephthalate) of polypropylene, b. extruding said polymer mixture in the form of a tape at a melt draw down of from about 26:1 to about 75:1 through a slit die characterized by having a modified entry port wherein the depth of the slit is greater at both ends than at the middle by an amount equal to 0.1 to 0.4 times said slits length, c. quenching said tape, d. hot drawing said tape in two stages wherein said tape is initially hot drawn to a draw ratio of from about 3.1:1 to about 4.2:1 while being subjected to a temperature of from about 80° to about 140° centigrade and thereafter hot drawn to a total draw ratio of about 5.0:1 while being heated to a temperature above 160° centigrade.
Claim 2
Independent Claim
165 words
A method of producing a low denier, high tenacity relatively uniformly fibrillatable poly(ethylene terephthalate) tape comprising a. intimately mixing poly(ethylene terephthalate) polymer with from about 0.1 to about 20 percent based on the weight of poly(ethylene terephthalate) of polypropylene, b. extruding said polymer mixture in the form of a tape at a melt draw down of from about 26:1 to about 75:1 through a slit die characterized by having a modified entry port wherein the depth of the slit is greater at both ends than at the middle by an amount equal to 0.1 to 0.4 times said slits length, c. quenching said tape, d. hot drawing said tape in two stages wherein said tape is initially hot drawn to a draw ratio of from about 3.1:1 to about 4.2:1 while being subjected to a temperature of from about 80° to about 140° centigrade and thereafter hot drawn to a total draw ratio of about 5.0:1 while being heated to a temperature above 160° centigrade.
Claim 3
Dependent Claim
27 words
The method of claim 1 wherein the polymer is extruded through the modified slit die at a melt draw down ratio of about 35:1 to about 55:1.
Claim 4
Dependent Claim
24 words
The method of claim 1 wherein the polymer is extruded through the modified slit die at a melt draw down ratio of about 50:1.
Claim 5
Dependent Claim
25 words
The method of claim 1 wherein the tape is hot drawn in the second stage at a temperature from about 160° to about 230° centigrade.
Claim 6
Dependent Claim
21 words
The method of claim 1 wherein from about 0.5 to about 10 percent polypropylene is intimately mixed with the poly(ethylene terephthalate).
Claim 7
Dependent Claim
21 words
The method of claim 1 wherein from about 2 to about 4 percent polypropylene is intimately mixed with the poly(ethylene terephthalate).
Claim 8
Dependent Claim
24 words
The method of claim 1 which comprises extruding said polymer mixture through a slit die radiused at both ends of said die's entry port.
Claim 9
Dependent Claim
35 words
The method of claim 1 which comprises extruding said polymer mixture through a slit die radiused at both ends of said die's entry port and having a radius of about 0.2 times said slit's length.
Claim 10
Independent Claim
159 words
A method of producing a low denier, high tenacity relatively uniformly fibrillated poly(ethylene terephthalate) tape yarn comprising a. intimately mixing poly(ethylene terephthalate) polymer with from about 0.1 to about 20 percent based on the weight of poly(ethylene terephthalate) of polypropylene, b. extruding said polymer mixture in the form of a tape at a melt draw down of from about 26:1 to about 75:1 through a slit die characterized by having a modified entry port wherein the depth of the slit is greater at both ends than at the middle, c. quenching said tape, d. hot drawing said tape in two stages wherein said tape is initially hot drawn to a draw ratio of from about 3.1:1 to about 4.2:1 while being subjected to a temperature of from about 80° to about 140° centigrade and thereafter hot drawn to a total draw ratio of about 5.0:1 while being heated to a temperature above 160° centigrade, e. fibrillating the drawn tape.
Claim 11
Independent Claim
159 words
A method of producing a low denier, high tenacity relatively uniformly fibrillated poly(ethylene terephthalate) tape yarn comprising a. intimately mixing poly(ethylene terephthalate) polymer with from about 0.1 to about 20 percent based on the weight of poly(ethylene terephthalate) of polypropylene, b. extruding said polymer mixture in the form of a tape at a melt draw down of from about 26:1 to about 75:1 through a slit die characterized by having a modified entry port wherein the depth of the slit is greater at both ends than at the middle, c. quenching said tape, d. hot drawing said tape in two stages wherein said tape is initially hot drawn to a draw ratio of from about 3.1:1 to about 4.2:1 while being subjected to a temperature of from about 80° to about 140° centigrade and thereafter hot drawn to a total draw ratio of about 5.0:1 while being heated to a temperature above 160° centigrade, e. fibrillating the drawn tape.
Claim 12
Dependent Claim
26 words
The method of claim 9 wherein the polymer is extruded through the modified slit die at a melt draw down of about 35:1 to about 55:1.
Claim 13
Dependent Claim
23 words
The method of claim 9 wherein the polymer is extruded through the modified slit die at a melt draw down of about 50:1.
Claim 14
Dependent Claim
25 words
The method of claim 9 wherein the tape is hot drawn in the second stage at a temperature from about 160° to about 230° centigrade.
Claim 15
Dependent Claim
21 words
The method of claim 9 wherein from about 0.5 to about 10 percent polypropylene is intimately mixed with the poly(ethylene terephthlate).
Claim 16
Dependent Claim
17 words
The method of claim 9 wherein about 3.0 percent polypropylene is intimately mixed with the poly(ethylene terephthlate).
Claim 17
Dependent Claim
19 words
The method of claim 9 wherein the tape is fibrillated by use of two sets of false twisting jets.
Claim 18
Dependent Claim
16 words
The method of claim 9 wherein the slit die is serrated along at least one face.
Claim 19
Dependent Claim
25 words
The method of claim 9 wherein the slit die is serrated along both faces and the serration of each face are aligned opposite each other.
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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) | 1981-10-30 | 1982-05-01 | 1982-10-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-10-30 | 1986-05-01 | 1986-10-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-10-30 | 1990-05-01 | 1990-10-31 | $7700.00 | Window Closed / Lapsed |