US2923969A - Certificate of correction - Google Patents
Certificate of correction Download PDFInfo
- Publication number
- US2923969A US2923969A US2923969DA US2923969A US 2923969 A US2923969 A US 2923969A US 2923969D A US2923969D A US 2923969DA US 2923969 A US2923969 A US 2923969A
- Authority
- US
- United States
- Prior art keywords
- spinneret
- orifice
- diameter
- spinning
- spinnerets
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000009987 spinning Methods 0.000 description 28
- 210000002832 Shoulder Anatomy 0.000 description 18
- 239000000203 mixture Substances 0.000 description 10
- 238000005498 polishing Methods 0.000 description 10
- 239000004753 textile Substances 0.000 description 10
- 230000000994 depressed Effects 0.000 description 8
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 8
- 239000000543 intermediate Substances 0.000 description 6
- 239000000463 material Substances 0.000 description 6
- 230000015572 biosynthetic process Effects 0.000 description 4
- 238000005755 formation reaction Methods 0.000 description 4
- 229910052697 platinum Inorganic materials 0.000 description 4
- 229920000642 polymer Polymers 0.000 description 4
- GUVRBAGPIYLISA-UHFFFAOYSA-N tantalum Chemical compound [Ta] GUVRBAGPIYLISA-UHFFFAOYSA-N 0.000 description 4
- 229910052715 tantalum Inorganic materials 0.000 description 4
- 229940059904 Light Mineral Oil Drugs 0.000 description 2
- 229920000297 Rayon Polymers 0.000 description 2
- 238000005296 abrasive Methods 0.000 description 2
- 239000003082 abrasive agent Substances 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N al2o3 Chemical compound [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 239000010953 base metal Substances 0.000 description 2
- 229920002678 cellulose Polymers 0.000 description 2
- 239000001913 cellulose Substances 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- VYZAMTAEIAYCRO-UHFFFAOYSA-N chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 2
- 230000015271 coagulation Effects 0.000 description 2
- 238000005345 coagulation Methods 0.000 description 2
- 230000000295 complement Effects 0.000 description 2
- 238000009833 condensation Methods 0.000 description 2
- 230000005494 condensation Effects 0.000 description 2
- 230000000875 corresponding Effects 0.000 description 2
- 239000006185 dispersion Substances 0.000 description 2
- ZOOODBUHSVUZEM-UHFFFAOYSA-N ethoxymethanedithioic acid Chemical compound CCOC(S)=S ZOOODBUHSVUZEM-UHFFFAOYSA-N 0.000 description 2
- 239000004744 fabric Substances 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 2
- 229910052737 gold Inorganic materials 0.000 description 2
- 239000010931 gold Substances 0.000 description 2
- 238000011065 in-situ storage Methods 0.000 description 2
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 229910001092 metal group alloy Inorganic materials 0.000 description 2
- 239000007769 metal material Substances 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000005404 monopole Effects 0.000 description 2
- 229910000510 noble metal Inorganic materials 0.000 description 2
- 239000003921 oil Substances 0.000 description 2
- 238000006116 polymerization reaction Methods 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 description 2
- 229910052703 rhodium Inorganic materials 0.000 description 2
- 239000010948 rhodium Substances 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 229920002994 synthetic fiber Polymers 0.000 description 2
- 239000004758 synthetic textile Substances 0.000 description 2
- 229910052721 tungsten Inorganic materials 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
Images
Classifications
-
- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
- D01D4/00—Spinnerette packs; Cleaning thereof
- D01D4/02—Spinnerettes
Definitions
- Viscose-type spinnerets which have been used very successfully for years in the coagulation spinning of cellulose xanthate solution, which is of relatively great viscosity, do not give satisfactory results in this new interfacial polymerization-spinning process.
- the objects of this invention are accomplished by preparing a viscose-type spinneret in the usual way and then subjecting the face thereof to a special polishing treatment whereby the shoulders of the orifices are rounded and the areas around the orifices are slightly recessed, as described in detail hereinafter.
- Spinnerets prepared in this way are satisfactorily adapted for use in interfacial polymerization-spinning, and continuous spinning of good, uniform multifilament yarn over long periods of time becomes possible through the use of these novel spinnerets.
- Figure 1 is a plan view drawn from a microinterferometer photograph of a single hole of a spinneret prepared in accordance with this invention (about 200 diameters enlargement)
- Figure 2 is a sectional elevation corresponding to Figure l, and
- Figure 3 is a normal size view of a typical spinneret.
- Spinnerets of the prior art have been made of a variety of materials including noble metal alloys, such as platinum and gold or platinum and rhodium, base metal alloys, such as stainless steel, and non-metallic materials, such as glass or plastic. Any of these may be used in accordance with the present invention, but tantalum has been found preferable in spinnerets for use in interfacial polymerization-spinning.
- a tantalum spinneret such as one of the forms common to the viscose art, is mounted in a conventionalviscose-type spinneret polisher which turns the spinneret during polishing so that it is polished in all directions parallel to the face.
- the spinneret surice face is shaped by polishing for a sufiiciently long time with chrome rouge (Grade T-9l manufactured by S. A. Day Manufacturing Company is suitable), used with a light mineral oil on a felt wheel.
- chrome rouge Gram T-9l manufactured by S. A. Day Manufacturing Company is suitable
- this treatment is followed by polishing with a dispersion of aluminum oxide grain powder, such as grit No, l000-W, in monopole oil and water on a jewelers cloth wheel to remove scratches and put a finer polish on the spinneret surfaces.
- the treatment with the coarser abrasive is continued for sufficient time to round off the orifice shoulders as shown in Figures 1 and 2 to a depth of at least 0.05 times the orifice diameter.
- the area around an orifice of a suitably processed spinneret appeared as shown in Figure 1 when photographed with a microinterferometer at a magnification of 200 diameters.
- the generally circular lines surrounding the orifice are the contour lines projected on the surface with this instrument, and each successive line indicates a difference in depth of 10 millionths of an inch.
- the orifice diameter was 0.003 inch, and the diameter of the depressed area within the outermost, generally circular, contour line 10 was about 0.014 inch.
- the spacing of the contour lines indicates that the slope of the depressed area, which was gradual near the outside, became increasingly steep and reached a depth of about 0.0004 inch at the edge 12 of the orifice.
- Figure 2 was drawn from Figure 1 by projecting points of intersection of the contour lines with a diameter. Only one-tenth the number of contour lines shown in Figure 1 can be shown in Figure 2, because of crowding of the lines, so the distance between the lines represents 0.0001 inch on the actual spinneret.
- the shape of the depressed area shown is typical of suitable spinnerets prepared in accordance with this invention.
- the shoulders of the orifice have been polished to an approximately parabolic curvature.
- the precise amount of dishing or cupping of the spinneret face may be varied as required and will depend upon the diameter of the orifice, the particular use for which intended, and the spacing of orifices in a multiple hole spinneret, such as that shown in Figure 3.
- Spinnerets depending upon the use, may have any number of orifices from 1 to 10, 20, 50 or or more.
- spinnerets should have the orifice shoulders rounded to a maximum depth at the orifice edge 12 of about 0.07 to 0.2 times the diameter of the orifice, the maximum diameter of the depression within the more or less circular boundary 10 should be about 3 to 6 times the diameter of the orifice, and the shape of the depression should approximate the shape shown in Figure 2.
- a spinneret assembly for spinning textile filaments comprising in combination a spinneret having orifice shoulders at the face of the spinneret rounded to an approximately parabolic curvature extending to a depth at the edge of the orifice of from about 0.05 to about 0.2 times the orifice diameter,
- a spinneret assembly for spinning textile filaments comprising in combination a spinneret having orifice shoulders at the face of the spinneret rounded to a depth at the edge of the orifice of from about 0.07 to about 0.2 times the diameter of the orifice.
- a spinneret assembly for spinning textile filaments comprising in combination a spinneret having orifice shoulders rounded to an approximately parabolic curvature reaching a depth at the edge of the orifice of from about 0.07 to 0.2 times the diameter of the orifice.
- a spinneret assembly for spinning textile filaments comprising in combination a spinneret having an orifice surrounded by a recessed area at the face of the spinneret of about 3 to 6 times the diameter of the orifice and sloping to a depth at the edge of the orifice of from about 0.07 to 0.2 times the diameter of the orifice.
- k is 3 a constant
- the diameter of the curved surfare is from 10 about 3 to 6 times the diameter of the orifice.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Textile Engineering (AREA)
- Spinning Methods And Devices For Manufacturing Artificial Fibers (AREA)
Description
E. THORPE Feb. 9, 1960 SPINNERET Filed June 12, 1953 INVENTOR ERNEST THORPE ATTORNEY United S t s P r SPINNERET Ernest Thorpe, Newport, Del., assignor to E. I. du Pont de Nemours and Company, Wilmington, Del., 2 corporation of Delaware Application June 12, 1953, Serial No. 361,130
5 Claims. (Cl. 18-8) This invention relates to spinnerets and more specifically to the novel orifices formed therein.
Revolutionary new methods for spinning synthetic textile filaments have recently been discovered which involve interfacial polymerization. In accordance with these methods filament formation and polymer formation are accomplished simultaneously when one of a pair of fastreacting condensation polymer-forming intermediates is extruded as a shaped stream into a bath containing the complementary intermediate. Reaction then takes place between the intermediates at the interface between bath and stream to form a filamentary polymer in situ. Difficulty has been experienced in attempting to maintain continuous operation when using conventional spinnerets, which has been traced, at least in part, to jetting of the filamentary streams because of the low viscosity of the solutions. Viscose-type spinnerets, which have been used very successfully for years in the coagulation spinning of cellulose xanthate solution, which is of relatively great viscosity, do not give satisfactory results in this new interfacial polymerization-spinning process.
It is therefore an object of this invention to provide a satisfactory spinneret for use in interfacial polymerization-spinning. Another object of this invention is to provide a novel spinneret. Other objects will become apparent from the description that follows and the claims.
The objects of this invention are accomplished by preparing a viscose-type spinneret in the usual way and then subjecting the face thereof to a special polishing treatment whereby the shoulders of the orifices are rounded and the areas around the orifices are slightly recessed, as described in detail hereinafter. Spinnerets prepared in this way are satisfactorily adapted for use in interfacial polymerization-spinning, and continuous spinning of good, uniform multifilament yarn over long periods of time becomes possible through the use of these novel spinnerets.
In the drawings, which illustrate a preferred embodiment of the invention,
Figure 1 is a plan view drawn from a microinterferometer photograph of a single hole of a spinneret prepared in accordance with this invention (about 200 diameters enlargement) Figure 2 is a sectional elevation corresponding to Figure l, and
Figure 3 is a normal size view of a typical spinneret.
Spinnerets of the prior art have been made of a variety of materials including noble metal alloys, such as platinum and gold or platinum and rhodium, base metal alloys, such as stainless steel, and non-metallic materials, such as glass or plastic. Any of these may be used in accordance with the present invention, but tantalum has been found preferable in spinnerets for use in interfacial polymerization-spinning. A tantalum spinneret such as one of the forms common to the viscose art, is mounted in a conventionalviscose-type spinneret polisher which turns the spinneret during polishing so that it is polished in all directions parallel to the face. The spinneret surice face is shaped by polishing for a sufiiciently long time with chrome rouge (Grade T-9l manufactured by S. A. Day Manufacturing Company is suitable), used with a light mineral oil on a felt wheel. Preferably this treatment is followed by polishing with a dispersion of aluminum oxide grain powder, such as grit No, l000-W, in monopole oil and water on a jewelers cloth wheel to remove scratches and put a finer polish on the spinneret surfaces.
The treatment with the coarser abrasive is continued for sufficient time to round off the orifice shoulders as shown in Figures 1 and 2 to a depth of at least 0.05 times the orifice diameter. The area around an orifice of a suitably processed spinneret appeared as shown in Figure 1 when photographed with a microinterferometer at a magnification of 200 diameters. The generally circular lines surrounding the orifice are the contour lines projected on the surface with this instrument, and each successive line indicates a difference in depth of 10 millionths of an inch. The orifice diameter was 0.003 inch, and the diameter of the depressed area within the outermost, generally circular, contour line 10 was about 0.014 inch. The spacing of the contour lines indicates that the slope of the depressed area, which was gradual near the outside, became increasingly steep and reached a depth of about 0.0004 inch at the edge 12 of the orifice.
Figure 2 was drawn from Figure 1 by projecting points of intersection of the contour lines with a diameter. Only one-tenth the number of contour lines shown in Figure 1 can be shown in Figure 2, because of crowding of the lines, so the distance between the lines represents 0.0001 inch on the actual spinneret. The shape of the depressed area shown is typical of suitable spinnerets prepared in accordance with this invention. The shoulders of the orifice have been polished to an approximately parabolic curvature. The precise amount of dishing or cupping of the spinneret face may be varied as required and will depend upon the diameter of the orifice, the particular use for which intended, and the spacing of orifices in a multiple hole spinneret, such as that shown in Figure 3. Spinnerets, depending upon the use, may have any number of orifices from 1 to 10, 20, 50 or or more.
For interfacial polymerization-spinning, spinnerets should have the orifice shoulders rounded to a maximum depth at the orifice edge 12 of about 0.07 to 0.2 times the diameter of the orifice, the maximum diameter of the depression within the more or less circular boundary 10 should be about 3 to 6 times the diameter of the orifice, and the shape of the depression should approximate the shape shown in Figure 2. This shape may be expressed matematically by the parabolic equation y =kx, where x is the horizontal distance from the edge of the orifice of a point on the curved surface, y is the elevation of the point above the maximum depth of the depression at 12, and k is a constant whose value is readily determined by substituting values of x and y, e.g., for the spinneret illustrated k is about 0.00003. Within these general specifications the precise dimensions for optimum conditions will depend upon the material extruded, the desired rate of spinning and the spinneret materal.
Other methods for producing the depressed areas around the orifices in the spinneret face may be used provided the method produces the desired rounded orifice shoulders as described herein. Variations include the conventional grinding, polishing or bufilng techniques of the art, but employing suitable abrasives and/or continuing the treatment for an unusually long time to produce the required result with the particular spinneret material.
Since many dilferent embodiments of the invention Patented Feb. 9, 19.60
9,923,969 i v H f may be made without departing from the spirit and scope thereof, it is to be understood that the invention is not limited by the specific illustrations except to the extent defined in the following claims.
What is claimed is:
a 1. In a spinneret assembly for spinning textile filaments the improvement comprising in combination a spinneret having orifice shoulders at the face of the spinneret rounded to an approximately parabolic curvature extending to a depth at the edge of the orifice of from about 0.05 to about 0.2 times the orifice diameter,
2. In a spinneret assembly for spinning textile filaments the improvement comprising in combination a spinneret having orifice shoulders at the face of the spinneret rounded to a depth at the edge of the orifice of from about 0.07 to about 0.2 times the diameter of the orifice.
3. In a spinneret assembly for spinning textile filaments the improvement comprising in combination a spinneret having orifice shoulders rounded to an approximately parabolic curvature reaching a depth at the edge of the orifice of from about 0.07 to 0.2 times the diameter of the orifice.
- 4. In a spinneret assembly for spinning textile filaments the improvement comprising in combination a spinneret having an orifice surrounded by a recessed area at the face of the spinneret of about 3 to 6 times the diameter of the orifice and sloping to a depth at the edge of the orifice of from about 0.07 to 0.2 times the diameter of the orifice.
5. In a spinneret assembly for spinning textile filaments 4 the improvement comprising in combination a spinner'et having orifice shoulders at the face of the spinneret rounded to approximate a parabolic curvature of the form y =kx where x is the perpendicular distance from the 5 edge of the orifice of a point on the curved surface, y
is the elevation of the point above the maximum depth of the curve at the orifice edge and has a value of from about 0.07 to 0.2 times the diameter of the orifice, k is 3 a constant, and the diameter of the curved surfare is from 10 about 3 to 6 times the diameter of the orifice.
References Cited in the file of this patent UNITED STATES PATENTS 1,604,216 Brainin Oct. 26, 1926 1,654,936 Jones Jan. 3, 1928 2,291,873 Brubaker Aug. 4, 1942 2,360,680 Holzmann Oct, 17, 1944 2,514,189 Spencer et a1. July 4, 1950 20 2,553,692 Webb May 22, 1951 2,566,283 Dowson Aug. 28, 1951 2,660,302 Gersman Nov. 24, 1953 2,677,148 Webb May 4, 1954 2,750,034 Gersman June 12, 1956 25 FOREIGN PATENTS 58,189 Switzerland Dec. 19, 1911 f OTHER REFERENCES UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No 2,923,969 February 9, 1960 Ernest Thorpe ppears in the printed specification It is hereby certified that error a orrection and that the said Letters of the above numbered patent requiring 0 Patent should read as corrected below.
Column 3, line 19, after "spinneret" insert having an orifice surrounded by a recessed area at the face of the spinneret and Signed and sealed this 15th day of November 1960.
(SEAL) Jittest:
KARL He AXLINE Attesting Oflicer ROBERT C. WATSON Commissioner'bf Patents
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2923969A true US2923969A (en) | 1960-02-09 |
Family
ID=3449055
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US2923969D Expired - Lifetime US2923969A (en) | Certificate of correction |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US2923969A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3084385A (en) * | 1959-07-08 | 1963-04-09 | Du Pont | Extrusion apparatus |
| US3349522A (en) * | 1965-07-27 | 1967-10-31 | Du Pont | Spinneret surface finishing |
| US5286323A (en) * | 1993-02-23 | 1994-02-15 | Corning Incorporated | Dome shaped extrusion dies |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CH58189A (en) * | 1911-12-19 | 1913-03-01 | Charles Sandoz Moritz & Cie | Industry for the manufacture of artificial silk |
| US1604216A (en) * | 1925-04-02 | 1926-10-26 | Clement S Brainin | Method of making spinnerets |
| US1654936A (en) * | 1926-03-23 | 1928-01-03 | Baker & Co Inc | Method of making spinnerets |
| US2291873A (en) * | 1939-07-14 | 1942-08-04 | Du Pont | Synthetic filament |
| US2360680A (en) * | 1940-08-30 | 1944-10-17 | Holzmann Hermann | Spinning nozzle for the production of artificial hollow threads |
| US2514189A (en) * | 1946-11-16 | 1950-07-04 | Method and apparatus for making | |
| US2553692A (en) * | 1948-07-03 | 1951-05-22 | American Viscose Corp | Staple fiber spinneret |
| US2566283A (en) * | 1948-03-16 | 1951-08-28 | Baker & Co Inc | Spinnerette |
| US2660302A (en) * | 1946-06-05 | 1953-11-24 | George Jordan | Extrusion |
| US2677148A (en) * | 1950-06-02 | 1954-05-04 | American Viscose Corp | Spinneret |
| US2750034A (en) * | 1951-06-15 | 1956-06-12 | Gersman Chadot Byron | Method and apparatus for extrusion of plastic materials |
-
0
- US US2923969D patent/US2923969A/en not_active Expired - Lifetime
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CH58189A (en) * | 1911-12-19 | 1913-03-01 | Charles Sandoz Moritz & Cie | Industry for the manufacture of artificial silk |
| US1604216A (en) * | 1925-04-02 | 1926-10-26 | Clement S Brainin | Method of making spinnerets |
| US1654936A (en) * | 1926-03-23 | 1928-01-03 | Baker & Co Inc | Method of making spinnerets |
| US2291873A (en) * | 1939-07-14 | 1942-08-04 | Du Pont | Synthetic filament |
| US2360680A (en) * | 1940-08-30 | 1944-10-17 | Holzmann Hermann | Spinning nozzle for the production of artificial hollow threads |
| US2660302A (en) * | 1946-06-05 | 1953-11-24 | George Jordan | Extrusion |
| US2514189A (en) * | 1946-11-16 | 1950-07-04 | Method and apparatus for making | |
| US2566283A (en) * | 1948-03-16 | 1951-08-28 | Baker & Co Inc | Spinnerette |
| US2553692A (en) * | 1948-07-03 | 1951-05-22 | American Viscose Corp | Staple fiber spinneret |
| US2677148A (en) * | 1950-06-02 | 1954-05-04 | American Viscose Corp | Spinneret |
| US2750034A (en) * | 1951-06-15 | 1956-06-12 | Gersman Chadot Byron | Method and apparatus for extrusion of plastic materials |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3084385A (en) * | 1959-07-08 | 1963-04-09 | Du Pont | Extrusion apparatus |
| US3349522A (en) * | 1965-07-27 | 1967-10-31 | Du Pont | Spinneret surface finishing |
| US5286323A (en) * | 1993-02-23 | 1994-02-15 | Corning Incorporated | Dome shaped extrusion dies |
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