DESC:FIELD
The present disclosure relates to polyester fiber.
DEFINITIONS
As used in the present disclosure, the following terms are generally intended to have the meaning as set forth below, except to the extent that the context in which they are used indicate otherwise.
Denier: Denier is a unit for the measurement of linear mass density of fibers. It is defined as the mass in grams per 9000 meters.
Tenacity: Tenacity is the customary measure of strength of a fiber or yarn. It is expressed as grams per denier (gpd).
Fiber Elongation: Fiber elongation is specified as the percentage of increase in length as compared to the initial length.
Uster value: Uster value is the measurement of evenness, thick places, and thin places in fiber.
Quenching: It is a method used for rapid cooling of melt to obtain fibers.
Draw Ratio: Expressed as the ratio of cross sectional area of undrawn material to that of the drawn material.
Wicking: Wicking is the absorption of a liquid by a material in the manner of a candle.

BACKGROUND
One of the major use of Fibers is for manufacturing apparel, carpet, upholstery, etc.
Viscose fibers are widely used in the manufacturing process of various fabrics. Fabrics made from the viscose fibers are pleasing to touch and breathes like cotton, however, fabrics made from viscose fibers wrinkle easily and many garments made from this fabric cannot be machine-washed or dried. Also, the manufacturing process of such fibers creates a lot of pollution. Further, the cost of the viscose fiber is also high.
One of the prerequisite for the selection of fiber before manufacturing the fabric is the moisture retention property of the fabric. The moisture management of the fabric depends a lot on the type of fiber used. The ability of a fabric to transport moisture away from the skin to the garment’s outer surface is one of the key performance criteria for manufacturing sports and active outdoor clothing. Natural fibers tend to absorb and retain body moisture which makes the body to feel uncomfortable, whereas synthetic fibers tend to move away the moisture from the body leading to efficient evaporation of the moisture. But, conventional synthetic fibers suffer from the problem of poor moisture management because of their poor wicking characteristics. Further, the conventional fibers suffer from the problem of low availability of surface area which is also responsible for its poor moisture management property.
There is, therefore, felt a need for a fiber having improved moisture retention properties for use in various applications.
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 polyester fiber characterized by non-circular cross section.
Another object of the present disclosure is to provide a gear shaped cross section fiber having improved moisture management properties.
Yet another object of the present disclosure is to provide a yarn made from the gear shaped cross section fiber.
Still another object of the present disclosure is to provide a woven fabric having improved moisture management property.
Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.
SUMMARY
The present disclosure relates to polyester fiber, characterized by:
• gear shaped cross section;
• linear mass density in the range of 0.6 to 10 denier per filament;
• tenacity in the range of 2.0 to 10.0 grams per denier (gpd);
• fiber elongation in the range of 5 to 50%; and
• uster value in the range of 2 to 12%.
The polyester fiber of the present disclosure is made from at least one polyester resin selected from the group consisting of polyethylene terephthalate (PET), polybutylene terephthalate (PBT) and polytrimethylene terephthalate (PTT).
Further, the polyester fiber of the present disclosure is used for the manufacturing of yarn. A woven fabric is made from this yarn. The woven fabric, made from the yarn of the polyester fiber of the present disclosure, has a high wicking property characterized by a wicking height in the range of 100 mm to 130 mm. The woven fabric has a denier per filament in the range of 1 to 6 of the yarn made from the polyester fiber of the present disclosure. The woven fabric comprises the yarn made from the polyester fiber of the present disclosure, in a weight fraction in the range of 50 to 100% of the woven fabric.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
The present disclosure will now be described with the help of the accompanying drawing, in which:
Figure 1 illustrates cross sectional view of the polyester fibers having gear shaped cross section; and
Figure 2 illustrates the longitudinal view of the polyester fibers having gear shaped cross section.
DETAILED DESCRIPTION
Viscose fibers are widely used in the manufacturing of fabrics. But, the production process of the viscose fiber causes a lot of pollution to the environment.
In accordance with one embodiment of the present disclosure, there is provided polyester fiber. The polyester fiber of the present disclosure, is characterized by:
• gear shaped cross section;
• linear mass density in the range of 0.6 to 10 denier per filament;
• tenacity in the range of 2.0 to 10.0 grams per denier (gpd);
• fiber elongation in the range of 5 to 50%; and
• uster value in the range of 2 to 12%.
The polyester fiber of the present disclosure is made from at least one polyester resin selected from the group consisting of polyethylene terephthalate (PET), polybutylene terephthalate (PBT) and polytrimethylene terephthalate (PTT).
The process for the manufacturing of the polyester fibers of the present disclosure, comprises the following steps:
Initially, a polymeric material is fed to an extruded wherein the polymeric material is melted at a temperature in the range of 260 to 300 °C and a molten mass is obtained. The molten mass thus obtained is passed through a spinneret, wherein the spinneret plate comprises a plurality gear shaped holes. The molten mass, after passing through the spinneret plate, results into a plurality of filaments having gear shaped cross section. These filaments, having gear shaped cross section, are quenched at a temperature in the range of 20 to 25 °C using air. The air flow rate used for quenching, is in the range of 0.4 to 0.7 m/s. Due to quenching, the filaments coming out of the spinneret holes freeze instantly and the filaments thus obtained showed a uniform and similar cross section as that of the spinneret holes. Further, the filaments are cut in desired length to obtain fibers having gear shaped cross section as shown in Figure 1 of the present disclosure, which can be used in various applications.
In accordance with one aspect of the present disclosure, the polyester fiber of the present disclosure, is used to make yarn. Further, a woven fabric is made from this yarn. The woven fabric thus obtained has improved moisture management property.
In accordance with the present disclosure, the woven fabric is characterized by:
• wicking height in the range of 100 mm to 130 mm; and
• denier per filament in the range of 1 to 6 of the yarn.
The woven fabric comprises the yarn made from the polyester fibers of the present disclosure, in a weight fraction in the range of 50 to100% of the woven fabric.
Further, the cross section geometry of the polyester fibers of the present disclosure imparts bounciness and high yarn to yarn friction to the fabric made therefrom. The fabric thus obtained, can withstand alkali weight reduction upto 40%.
The present disclosure is further described in light of the following experiments which are set forth for illustration purpose only and not to be construed for limiting the scope of the disclosure. The following experiments can be scaled upto industrial/commercial scale and the results obtained can be extrapolated to industrial scale.
Experiment: 1
Polyethylene terephthalate (PET) was melted at a temperature of 270 °C in an extruder to obtain a molten mass. The molten mass was then passed through a spinneret plate having a plurality of gear shaped holes. Wherefrom, filaments having gear shaped cross section were drawn.
These filaments, having gear shaped cross section, were quenched using air. An air flow rate of 0.6 m/s and a temperature of 17 °C was maintained for quenching these filaments. The filaments having gear shaped cross section freezed instantly and filaments of uniform gear shaped cross section as that of the spinneret holes, were obtained. These filaments were further cut to desired length to obtain the PET fibers having gear shaped cross section and a yarn was made from these PET fibers gear shaped cross section fibers.
Experiment: 2
A woven fabric was made from the yarn of Experiment 1. The moisture management property of the woven fabric made from the yarn of Experiment 1, was tested with the woven fabric made from the yarn of conventional PET fibers having circular cross section and the woven fabric made from yarn of conventional PET fibers having non-circular cross section fiber. A wicking test was conducted to compare their moisture management properties in terms of wicking height. All the fabrics were soaked in water for 20 minutes and then compared to check their corresponding wicking heights. The results thus obtained are tabulated in Table 1 herein below.
Table 1: Wicking height after 20 minutes:

S. No. Woven Fabric made from PET fibers having circular cross section Woven Fabric made from PET fibers having non-circular cross section Woven Fabric made from PET fibers having gear shaped cross section
1. 81 mm 110 mm 122 mm
The woven fabric made from the yarn of PET fibers having gear shaped cross section showed the highest wicking height compared to the fabrics made from the yarn of conventional fibers. Therefore, confirms improved moisture management property of the fabric made from the yarn of PET fibers having gear shaped cross section.
Further, these fabrics were washed and then tested to compare their moisture management property. The results thus obtained are shown in Table 2 herein below.

Table 2:

S.No.
Wicking Height
(in cm) Woven Fabric made from PET fibers having circular cross section Woven Fabric made from PET fibers having non-circular cross section Woven Fabric made from PET fibers having gear shaped cross section
1. After 5 wash 0 to2 0 to 3 10 to 12
2. After 20 wash 0 to 1 1 to 2 6 to 10
3. Wicking tendency Poor Poor Very good

After 20 washings, it was observed that wicking heights for the fabrics made from the yarn of regular PET fibers were 10 mm and 20 mm whereas, for fabric made from the yarn of PET fibers having gear shaped cross section, the wicking height was 100 mm. This confirms the better stability of the structure of the fabric made from the yarn of PET fibers having gear shaped cross section, under repeated usage.
TECHNICAL ADVANCEMENTS
The present disclosure described herein above has several technical advantages including, but not limited to, the realization of:
? polyester fibers having gear shaped cross section;
? yarn made from the polyesters fibers having gear shaped cross section; and
? woven fabric having improved moisture management property compared to the fabric comprising conventional 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 invention to achieve one or more of the desired objects or results. While certain embodiments of the inventions have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Variations or modifications to the formulation of this invention, within the scope of the invention, may occur to those skilled in the art upon reviewing the disclosure herein. Such variations or modifications are well within the spirit of this invention.
The numerical values given for various physical parameters, dimensions and quantities are only approximate values and it is envisaged that the values higher than the numerical value assigned to the physical parameters, dimensions and quantities fall within the scope of the invention unless there is a statement in the specification 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.
,CLAIMS:1. Polyester fiber, characterized by:
• gear shaped cross section;
• linear mass density in the range of 0.6 to 10 denier per filament;
• tenacity in the range of 2.0 to 10.0 grams per denier (gpd);
• fiber elongation in the range of 5 to 50%; and
• uster value in the range of 2 to 12%.
2. The polyester fiber as claimed in claim 1, wherein the polyester fiber is made from at least one polyester resin selected from the group consisting of polyethylene terephthalate (PET), polybutylene terephthalate (PBT) and polytrimethylene terephthalate (PTT).
3. A yarn made from plurality of said polyester fiber as claimed in claim 1.
4. A woven fabric made from the yarn as claimed in claim 3, wherein said woven fabric is characterized by:
• denier per filament in the range of 1 to 6 of said yarn; and
• wicking height in the range of 100 mm to 130 mm.
5. The woven fabric as claimed in claim 4, wherein the weight fraction of said yarn is in the range of 50 to 100% of said woven fabric.