CLIAMS:1. A yarn comprising a blend of (A) a polyester fibre having shrinkage capacity in the range of 20 to 22 % at a temperature of 130 oC and (B) a polyester fibre having shrinkage capacity in the range of 2 to 3 % at a temperature of 130 oC;
wherein, the shrinkage capacity of the yarn ranges from12 to 15%; and
the ratio of A to B ranges from 1:5 to 1:2.

2. The yarn as claimed in claim 1, wherein the polyester fibres A and B are made from at least one polymer selected from the group consisting of poly(ethylene terephthalate), poly(butylene terephthalate) and poly(ethylene naphthalate).

3. The yarn as claimed in claim 1, wherein the polyester fibre/s A and/or B further comprise/s at least one co-monomer up to 2 w/w%.

4. The yarn as claimed in claim 3, wherein the co-monomer is at least one selected from the group consisting of isophthalic acid, 2-methyl-1,3-propanediol, trimethylene glycol and cyclohexane dimethanol.

5. The yarn as claimed in claim 1, wherein the polyester fibre having shrinkage capacity in the range of 20 to 22 % is characterized by a denier size in the range from 1.2 to 4.

6. The yarn as claimed in claim 1, wherein the polyester fibre having shrinkage capacity in the range of 2 to 3% is characterized by a denier size in the range from 1.5 to 4.

7. A woven fabric comprising the yarn as claimed in claim 1. ,TagSPECI:FIELD:
The present disclosure relates to a yarn suitable for weaving fabrics.
BACKGROUND:
Definition:
In the context of the present disclosure the terms “high shrinkage or high shrinkable” include a polymer having a shrinkage capacity of at least 20 %.
The terms “low shrinkage or low shrinkable” include a polymer having a shrinkage capacity below 20 %.
Woven shawls and winter dress materials are bulky woven fabrics particularly for protection from cold weather conditions. The desired bulk, thermal insulation or warmth in the woven fabrics/garments depends on its fibre constituent, yarn diameter and the level of yarn twist.
Traditionally, winter garments are made from wool fibres. The wool fibres can be replaced with acrylic fibres for economic reasons. However, with the increase in demand for acrylic fibres, acrylic fibres have also become substantially costlier. Therefore, the textile industry needs an alternative economic substitute for acrylic fibres. Various economic substitutes for acrylic fibres have been suggested.
For instance, EP1860217 suggests a fabric prepared from two types of yarns different in self-elongating property upon absorbing water and capable of facilitating the air-permeability when wetted with water. The ratio of the first type of yarn to the second type of yarn is adjusted to 0.9 or less.
JP2000220055 suggests a woven fabric consisting 3-50 wt.% fusing fiber such as a sheath-core fiber having low melting co-polyester and greater than 30 wt.% highly shrinkable polyester staple fibers having 18-80% dry-heat shrinkage factor.
Another JP2002294534 suggests a bulky woven/knitted fabric consisting a blend of high- shrinkage staple fibers having shrinkage factor greater than 40% and cellulosic staple fibers.
Still another JPH06123057 suggests woven fabric comprising spun yarn. The spun yarn is obtained from co-polyester short fibers A having 25-70% heat shrinkage percentage composed of a dicarboxylic acid component of terephthalic acid/isophthalic acid in a molar ratio of 96/4 to 88/12 and an ethylene glycol component with polyester short fibers B having 1-3% heat shrinkage percentage.
Some of the suggested yarns/fabrics at least in partial amount contain acrylic acid while others require specially treated raw material due to which the suggested yarns/fabrics are still expensive. Further, the suggested polyester fibres contain high amount of isophthalic acid. The presence of high isophthalic acid in such a high amount adversely affects the aesthetic appearance of the polyester as it imparts color to the polyester. Still further, the yarn/fabric are either too bulky or cannot provide desired level of warmth.
Therefore, there is felt a need for economical yarn/fabric having relatively low amount of isphthalic acid impurity and acceptable aesthetic appearance.
OBJECTS:
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:
An object of the present disclosure is to provide a yarn suitable for weaving fabrics.
Another object of the present disclosure is to provide a yarn which contains a lower amount of co-monomer.
Still another object of the present disclosure is to provide a yarn which can be easily processed to achieve a desired dye depth.
Still another object of the present disclosure is to provide a yarn which can be used to at least partially substitute acrylic fibres or wool fibres.
Yet another object of the present disclosure is to provide a process for preparing a woven fabric comprising a yarn.
Other objects of the present invention will be more apparent to a person skilled in the art from the description provided herein after.
SUMMARY:
Accordingly, the present disclosure provides a yarn suitable for weaving fabrics. The yarn of the present disclosure is economical, possesses desired shrinkage factor and is capable of providing desired warmth.
Particularly, the present disclosure provides a yarn having acceptable level of shrinkage capacity suitable for woven applications. The yarn is prepared from two types of polyester fibres (A and B) different in shrinkage factors/capacities, wherein the ratio of A to B ranges from 1:5 to 1:2.
DETAILED DESCRIPTION:
The present disclosure provides a yarn having shrinkage capacity in the range of 12 to 15%. The yarn of the present disclosure is a blend of (A) a polyester fibre having shrinkage capacity in the range of 20 to 22 % at a temperature of 130 oC, and (B) a polyester fibre having shrinkage capacity in the range of 2 to 3 % at a temperature of 130 oC.
Numerous experiments were carried out to arrive at an optimum ratio of high shrinkage polyester fibre i.e., A and low shrinkage polyester fibre i.e., B. The optimum ratio of A to B ranges from 1:5 to 1:2.
The polyester fibre having shrinkage capacity in the range of 20 to 22 % is characterized by a denier size in the range from 1.2 to 4, whereas the polyester fibre having shrinkage capacity in the range of 2 to 3% is characterized by a denier size in the range from 1.5 to 4.
The polyester fibres useful for the purpose of the present disclosure are made from at least one polymer selected from the group consisting of poly(ethylene terephthalate), poly(butylene terephthalate) and poly(ethylene naphthalate).
The polyester fibre/s A or B or both may comprise at least one co-monomer selected from the group consisting of isophthalic acid, 2-methyl-1,3-propanediol, trimethylene glycol and cyclohexane dimethanol. The amount of co-monomer in the polyester fibre having shrinkage capacity in the range of 20 to 22 %, ranges up to 2 w/w%.
The yarn having desired shrinkage capacity can be obtained by a process which involves bulking and dyeing A and B together in HT/HP (high temperature/high pressure) dyeing machine at 130oC for 30 minutes.
The process for obtaining yarn having desired shrinkage capacity, further may comprise a step of disperse printing in rotary or flatbed printing machine.
The shrinkage capacity/factor of the yarn is the synergistic result of the ratio of the polyester fibres A and B, yarn twist capacity, thickness of the fibres and dyeing fibre in a single step in HT/HP jet dyeing machine.
The yarn used in a woven fabric of the present disclosure is obtained by a selection of proper single and plied yarn twist levels based experimental data, followed by selection of suitable yarn bulking and dyeing hardware and process conditions. The processing conditions optimized include dyeing at a temperature of 130 oC and holding time of 30 minutes, bulking in high temperature/high pressure (HT/HP) dyeing machine at 130 oC for 30 minutes followed by Disperse Printing in Rotary or Flatbed Printing machine, drying at 150 oC and steaming at 170 oC for 6-8 minutes in Steam Ager.
The present disclosure also provides a woven fabric comprising the yarn of the present disclosure.
The present disclosure is further described in the light of the following examples which are set forth for illustration purpose only and not to be construed for limiting the scope of the disclosure.
Example:
Preparation of high shrinkage woven fabric
High shrinkable fiber having shrinkage 22% and normal shrinkable fiber having shrinkage 3% were blended in the proportion of 1:5 to obtain a yarn. Yarn twisting per inch was 2.8. Yarn was then converted into woven fabric by bulking in jet dyeing machine then disperse printing in flatbed printing machine, drying at 150 oC followed by steaming at 170 oC for 6-8 minutes in steam ager. Final shrinkage of the woven fabric was 15%.
The advantage of obtaining the yarn by the aforesaid process/strategy is that it does not require any alteration or addition of downstream processing hardware.
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 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 particular features of this disclosure, it will be appreciated that various modifications can be made, and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other modifications in the nature of the disclosure or the preferred embodiments 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.
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.