WO2013164846A1

WO2013164846A1 - Spinerette for improved spinning productivity

Info

Publication number: WO2013164846A1
Application number: PCT/IN2013/000177
Authority: WO
Inventors: Karunanithi THANDAYUTHAPANI; Sumanta Chatterjee
Original assignee: Reliance Industries Limited
Priority date: 2012-03-22
Filing date: 2013-03-19
Publication date: 2013-11-07
Also published as: CN104246028A; KR20140136496A; JP2015514163A

Abstract

A spinneret for extruding a plastic polymer melt there-through to form fibers is disclosed in accordance with an embodiment of the present disclosure. The spinneret includes a plurality of apertures arranged along a plurality of contours to improve spinning productivity by enhancing aperture density while eliminating risk of filament fusion by maintaining appropriate aperture spacing.

Description

SPINERETTE FOR IMPROVED SPINNING PRODUCTIVITY

FIELD OF THE DISCLOSURE

The present disclosure relates to a melt spinning process, more particularly, the present disclosure relates to a spinneret used in a melt spinning process.

DEFINITION(S):

Micro denier fiber/Micro-fibre refers to synthetic fibers finer than one or 1.3 denier or decitex/thread. a super - microdenier polyester filament refers to syntheric fibers having dimension .37 dpf (denier per filament)

BACKGROUND

Polymeric fibers are generally manufactured by a melt spinning process. In the melt spinning process, the polymer is melted, the polymer melt so formed is pumped through a spinneret / die provided with a plurality of holes configured thereon. The polymer melt is forced to pass through the plurality of holes configured on the spinneret / die to result in the formation of molten fibers. The molten fibers extruded from the holes configured on the spinneret / die are cooled or quenched, solidified and collected on a take-up wheel / bobbin. The stretching of the fibers in both the molten and solid states provides orientation of the polymer chains along the fiber axis. Polymers such as polyethylene terephthalate and nylon 6, 6 are melt-spun in high volumes.

The polymer melt is extruded through the plurality of holes configured on the spinneret / die for facilitating formation of the molten fibers. More the number of holes configured on the spinneret, more will be formation of molten fibers, and accordingly more will be the spinning productivity. The spinning productivity is directly proportional to the hole density of the spinneret, more particularly, the number of holes per unit area of the spinneret, particularly, increasing the number of holes in the spinneret increases the spinning productivity. However, the conventional spinnerets are having structural limitations that prevent the hole-density from exceeding a particular limit. Any increase in the number of holes poses risk of fusion of filaments at spinning thus deteriorating product quality and process performance during fiber manufacture. As the conventional spinneret fail to increase the hole- density thereof, the production of micro and super micro denier fibers with the conventional spinnerets may not be increased. Accordingly, the spinning productivity is limited in case of the conventional spinnerets.

There are a number of prior art documents that disclose spinneret for extruding a plastic polymer melt there-through to form fibers.

For example, the US Granted Patent US6926854 (hereinafter referred to as '854 US Granted Patent) discloses a manufacturing method for polyester fine denier multifilament. The length of a protective delay shroud of the radial outer-flow quenching system used in melt spinning process for manufacturing fine hollow polyester filaments is expressed as (2~8060xthroughput/filaments square), and the length of quenching air tube is from 15 to 40 centimeters. The velocity of quenching air is between 0.2 m/sec to 0.6 m/sec. For the layout of the spinneret orifices, the diameter difference of outermost layer orifice and the innermost layer orifice is set less than 20 mm; and the distance between the diameter of innermost orifice layout and the diameter of quenching air tube is at least 12 and less than 33 mm. The orifice density of spinneret layout (orifice density) is set as 7-15 orifices per square centimeter which is far less. With use of the spinneret disclosed in the '854 US Granted Patent, the spinning productivity is less because of lower orifice density. The spinneret used for manufacturing polyester fine denier multifilament as disclosed in the '854 US Granted Patent is complex and ineffective. Similarly, the Japanese Published Patent Application JP4300319 (hereinafter referred to as '319 Japanese Published Patent Application) discloses a method for production of polyester fiber and a spinneret used therefor. The Polyester fiber is melt spun at a high speed of >=5000m/min. In the process, a spinneret in which spinning holes are arranged on concentric circles composed? of plural circles and the diameter of the spinning holes arranged on the inner circles is larger than that of spinning holes arranged on the outer circles is used to homogeneously blast air from the whole periphery of the filament group just after the spinning and quench the filaments. Thereby, multifilament yarn of polyester fiber having a large number of single filaments is spun. However, the spinneret and the method for production of polyester fiber as disclosed in the '319 Japanese Published Patent Application is complex and ineffective.

The Chinese Published Patent Application CN 1752301 (hereinafter referred to as '301 Chinese Published Patent Application) discloses a method for making acrylic fiber by fine denier dry method and spinning nozzle. The method involves regulating the technological conditions of original Dupont dry spinning of acrylic fiber, such as raising temperature difference of internal and external side temperatures of mass, controlling nitrogen gas temperature and flow rate, water-washing temperature and draft multiple and speed and using cotton type oil agent to oil, etc. The '301 Chinese Published Patent Application also discloses designs for spinneret with high-density nozzle hole, its aperture is 0.09-0.13 mm, and the holes are arranged and distributed on 15-21 concentric circles, so that it can implement industrial production of fine- denier dry acrylic fiber. However, the spinneret and method for making acrylic fiber by fine denier dry method as disclosed in the '301 Chinese Published Patent Application is complex and ineffective.

Accordingly, there is a need for enhancing the spinning productivity by increasing hole-density of a spinneret. Still further, there is a need for improving the spinning productivity while maintaining product quality and process performance during fiber manufacture. Further, there is a need for spinning productivity by increasing hole- density without any risk of fusion of filaments during spinning.

OBJECTS

Some of the objects of the present disclosure which at least one embodiment herein satisfies are as follows:

It is an object of the present disclosure to ameliorate one or more problems of the prior art or to at least provide a useful alternative.

An object of the present disclosure is to provide a spinneret for improving spinning productivity.

Another object of the present disclosure is to provide a spinneret with increased hole- density.

Still another object of the present disclosure is to provide a spinneret having strategically placed holes for increasing the number of holes configured thereon.

Another object of the present disclosure is to provide a spinneret for enhancing process performance during fiber manufacture.

Another object of the present disclosure is to provide a spinneret that eliminates risk of fusion of filaments at spinning with higher hole-density.

Yet another object of the present disclosure is to provide a spinneret for use in melt spinning process for manufacturing Micro and Super-micro denier fibers. Other objects and advantages of the present disclosure will be more apparent from the following description when read in conjunction with the accompanying figures, however which are not intended to limit the scope of the present disclosure.

SUMMARY

Typically, the aperture density is in the range of 20-45 apertures per square cm surface area of the spinneret and the aperture spacing is in the range 1mm to 5mm.

In accordance with an embodiment, the spinneret has an aperture density in the range of 20-60 apertures per square cm surface area of the spinneret and the aperture spacing is in the range 1mm to 5mm.

In accordance with yet another embodiment, the spinneret has an aperture density is in the range of 20-45 apertures per square cm surface area of the spinneret and the aperture spacing is in the range 1.5 mm to 2.2 mm.

Generally, the contours are a plurality of concentrically arranged circles.

In accordance with an embodiment, the apertures are arranged along sixteen concentrically arranged circles.

Generally, the polymer melt is polyester melt.

Typically, the spinneret is a 229 mm diameter spinneret that includes 3900 apertures arranged thereon. In accordance with another embodiment, the spinneret is a 229 mm diameter spinneret that includes 4208 apertures arranged thereon.

Preferably, the spinneret is used with Polyester Staple Fiber (PSF) spinning machine.

Generally, the spinneret includes a plurality of mounting holes disposed along an outer periphery thereof for facilitating mounting thereof.

Preferably, at least two of the mounting holes disposed diametrically opposite to each other are countersunk holes.

Typically, the spinneret further includes drillings configured on circumferential edge of the spinneret.

BRIEF DESCRIPTION OF DRAWINGS

The disclosure will now be explained in relation to the non-limiting accompanying drawings, in which:

FIGURE la illustrates a front view of a spinneret in accordance with an embodiment of the present disclosure, wherein a 229 mm diameter spinneret has 3900 holes configured thereon;

Figure lb illustrates a sectional view of the spinneret of Figure la along section line X-X;

FIGURE 2a illustrates a front view of an improved spinneret in accordance with the present invention, wherein a 229 mm diameter spinneret has 4208 holes configured thereon; and Figure 2b illustrates a sectional view of the spinneret of Figure 2a along section line X-X'.

DETAILED DESCRIPTION OF DRAWINGS

The disclosure will now be described with reference to the accompanying drawings which do not limit the scope and ambit of the disclosure. The description provided is purely by way of example and illustration.

The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.

The present disclosure envisages an improved spinneret for extruding a plastic polymer melt there-through to form fibers. The improved spinneret has more no of holes configured thereon, particularly, the arrangement of holes is such that more number of holes can be accommodated within limited area, thereby improving spinning productivity while eliminating risk of filament fusion by maintaining appropriate spacing between the holes.

Figure la illustrates a front view of a spinneret in accordance with an embodiment of the present disclosure, wherein the spinneret is a 229 mm diameter spinneret that has 3900 holes configured thereon as against the conventional spinneret with around three thousand three hundred circular holes. Figure lb illustrates a sectional view of the spinneret of Figure la along section line X-X. Figure la illustrates the spinneret having series of holes with reference numeral (1) disposed along sixteen concentrically arranged circles, wherein the holes are distributed along the circles according to their numbers. For example, the first circle that is the inner most circle has 202 holes, the second circle has 208 holes and so on. Such a configuration facilitates accommodation of more holes in the specific area i.e. area corresponding to 229 mm diameter spinneret. Further, the profile of the holes configured on the spinneret is suitable for forming micro- and super-micro deniers. The spinneret further includes a marking indicating the number of holes configured thereon in order to avoid confusion. For example, the spinneret illustrated in Figure la includes a marking 3900 for indicating that the spinneret has 3900 holes configured thereon. Such marking can be formed by etching or any other process.

Further, there are sixteen drilled fixing/mounting holes 2 arranged along the outer periphery of the spinneret that are concentrically arranged with respect to the sixteen concentrically arranged circles. The two fixing holes of the sixteen drilled fixing holes 2 that are disposed diametrically opposite to each other are countersunk holes. Further, two drillings 3 and one drilling 4 and 5 each are also provided on the circumferential edge of the spinneret.

Figure 2a illustrates a front view of a spinneret in accordance with an embodiment of the present disclosure, wherein the spinneret is a 229 mm diameter spinneret having four thousand two hundred and eight circular holes, as against the conventional spinneret with around three thousand three hundred circular holes. Figure 2a illustrates the spinneret having series of holes with reference numeral (1 1) disposed along sixteen concentrically arranged circles, wherein the holes are distributed along the circles according to their numbers. Further, there are sixteen drilled fixing/mounting holes 12 arranged along the outer periphery of the spinneret that are concentrically arranged with respect to the sixteen concentrically arranged circles. The two fixing holes of the sixteen drilled fixing holes 12 that are disposed diametrically opposite to each other are countersunk holes. Further, two drillings 13 and one drilling 14 and 15 each are also provided on the circumferential edge of the spinneret. Figure 2b illustrates a sectional view of the spinneret of Figure 2a along section line X-X'. Figure 2a illustrates the spinneret having series of holes with reference numeral (1 1) disposed along sixteen concentrically arranged circles, wherein the holes are distributed along the circles according to their numbers. For example, the first circle that is the inner most circle has 218 holes, the second circle has 224 holes and so on. Such a configuration facilitates accommodation of more holes in the specific area i.e. area corresponding to 229 mm diameter spinneret. Further, the profile of the holes configured on the spinneret is suitable for forming micro- and super-micro deniers. The spinneret illustrated in Figure 2a includes a marking 4208 for indicating that the spinneret has 4208 holes configured thereon. Such marking can be formed by etching or any other process.

The rest of the features of the spinneret illustrated in Figure 2a and Figure 2b in accordance with this embodiment are exactly similar to the features of the spinneret illustrated in Figure la and Figure lb.

The present disclosure envisages a spinneret that includes a plurality of holes strategically configured thereon for increasing the hole-density and accordingly enhancing the spinning productivity, while still maintaining the product quality and process performance during fiber manufacture. The strategically placed holes configured on the spinneret eliminate any risk of fusion of filaments during spinning by maintaining appropriate spacing between the holes.

The spinneret of present disclosure is particularly suitable for use in Polyester staple fiber (PSF) spinning machines, but can be envisaged to be used in all other kinds of spinning machines.

The spinneret in accordance with the present disclosure is having same area as the area of a conventional spinneret, however, the holes are strategically located, as shown in the Figures la, Figure lb, Figure 2a and Figure 2b and described above, for increasing the hole density in the spinneret. Further, the distance between the holes is adjusted in such a way that the fusion of filaments at spinning is avoided. Further, the profile of the holes configured on the spinneret of the present disclosure is suitable for micro- and super-micro deniers.

Tests were conducted to determine the efficiency of the spinneret in accordance with the present disclosure. The spinnerets in accordance with the present disclosure were tested on commercial spinning machines. It was observed that the spinnerets in accordance with the present disclosure exhibited higher throughput and normal performance. The spun tow was tested for defects and found to be at par with the existing product of comparable denier. With the use of spinnerets in accordance with the present disclosure, the productivity was increased by a minimum of 10 percent in spinning. The spun tow was processed in commercial draw machines, and the machine performance was observed to be normal. The final fiber was tested and found to be defect free.

However, the above preferred embodiments do not limit the scope and ambit of the disclosure. The description provided is purely by way of example and illustration.

The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as not to unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.

The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

TECHNICAL ADVANTAGES AND ECONOMIC SIGND7ICANCE

The method in accordance with the present disclosure has several technical advantages including but not limited to the realization of:

• spinneret for improving spinning productivity ;

• a spinneret having strategically placed holes for increasing the number of holes configured thereon;

• spinneret with increased hole-density thereof;

• spinneret for enhancing and process performance during fiber

manufacture;

• spinneret that eliminates risk of fusion of filaments at spinning; and

• spinneret for use in melt spinning process for manufacturing micro and super micro denier fibers.

Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.

The use of the expression "at least" or "at least one" suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results. Any discussion of documents, acts, materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.

The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities also fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary.

While considerable emphasis has been placed herein on the specific features of the preferred embodiment, it will be appreciated that many additional features can be added and that many changes can be made in the preferred embodiment without departing from the principles of the disclosure. These and other changes in the preferred embodiment of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation thereof.

Claims

Claims:

1. A spinneret for extruding a plastic polymer there-through to form fibers, said spinneret comprising a plurality of apertures arranged along a plurality of contours and adapted to improve spinning productivity by enhancing aperture density while eliminating risk of filament fusion by maintaining appropriate aperture spacing.

2. The spinneret as claimed in claim 1, wherein said aperture density is in the range of 20-45 apertures per square cm surface area of said spinneret and said aperture spacing is in the range 1mm to 5mm.

3. The spinneret as claimed in claim 1, wherein said aperture density is in the range of 20-60 apertures per square cm surface area of said spinneret and said aperture spacing is in the range 1mm to 5mm.

4. The spinneret as claimed in claim 1, wherein said aperture density is in the range of 20-45 apertures per square cm surface area of said spinneret and said aperture spacing is in the range 1.5 mm to 2.2 mm.

5. The spinneret as claimed in claim 1, wherein said contours are a plurality of concentrically arranged circles.

6. The spinneret as claimed in claim 1, wherein said apertures are arranged along sixteen concentrically arranged circles.

7. The spinneret as claimed in claim 1, wherein said polymer is polyester.

8. The spinneret as claimed in claim 1, wherein said spinneret is a 229 mm diameter spinneret comprising 3900 apertures arranged thereon.

9. The spinneret as claimed in claim 1, wherein said spinneret is a 229 mm diameter spinneret comprising 4208 apertures arranged thereon.

10. The spinneret as claimed in claim 1 , wherein said apertures configured on said spinneret exhibit profile that facilitates forming of micro- and super-micro denier fibers.

1 1. The spinneret as claimed in claim 1, wherein said spinneret is adapted to be used with Polyester Staple Fiber (PSF) spinning machine.

12. The spinneret as claimed in claim 1, wherein said spinneret comprises a plurality of mounting holes configured along an outer periphery thereof for facilitating mounting thereof.

13. The spinneret as claimed in claim 10, wherein at least two of said mounting holes configured diametrically opposite to each other are countersunk holes.

14. The spinneret as claimed in claim 1, wherein said spinneret further comprises drillings configured on circumferential edge of said spinneret.