US20040172984A1

US20040172984A1 - Knitted fabric having an excellent wash fastness and light fastness, and a process of preparing for the same

Info

Publication number: US20040172984A1
Application number: US10/475,680
Authority: US
Inventors: Sang-Woo Jung; Jae-Hoon Jung; Joon-Young Yoon
Original assignee: Kolon Industries Inc
Current assignee: Kolon Industries Inc
Priority date: 2001-04-26
Filing date: 2002-04-26
Publication date: 2004-09-09
Also published as: CN1505710A; WO2002088446A1; EP1381724A1; EP1381724A4

Abstract

The present invention discloses a knitted fabric having excellent wash fastness and light fastness, and a process of preparing for the same. More particularly, the knitted fabric of the present invention has a ultra fine yarn including a dope dyed component selected from the group consisting of carbon black, pigments and dyestuffs on the face and/or back and has a wash fastness of more than level 2-3 and a light fastness of more than level (5). In addition, in the process of the present invention, a sea-island type conjugate fiber is used in which a dope dyed component such as carbon black or the like is contained in a fiber forming component as a face yarn and/or back yarn. The knitted fabric of the present invention is used for materials of artificial leathers or ladies' clothes.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a knitted fabric having excellent wash fastness and light fastness, and a process of preparing for the knitted fabric.

If a fiber becomes fined, its bending strength becomes weakened. Accordingly, since fabrics produced with ultra fine denier fiber have very soft touch, researches in connection with producing such ultra fine denier fiber on a commercial scale are developing very actively. Also, development of the technology which is capable of producing synthetic yarn extremely finely leads to great improvement of the value of the goods of sensitive materials for clothes.

2. Description of Related Art

Generally, a process of preparing ultra fine denier fiber is divided into three processes: a direct spinning process; a bicomponent division type spinning process; and a bicomponent dissolution type spinning process. In the direct spinning process, it is possible to prepare ultra fine denier fiber of 0.3˜0.5 denier. In the bicomponent division type spinning process, it is possible to prepare ultra fine denier fiber of 0.2 denier. In the bicomponent dissolution type spinning process, it is possible to prepare ultra fine denier fiber of 0.001 denier or below.

Producing goods with ultra fine denier fiber are developing in variety in connection with textile applications. However, producing goods with ultra fine denier fiber are not developing in connection with knitting applications, particularly, warp knit fabric applications, due to the several drawbacks generated in warping and subsequent processes.

In case that the ultra fine denier fiber of 0.3˜0.5 denier prepared by means of the direct spinning process is applied to a warp knit, warping property and knitting property are very poor since numerous filaments are scattered. Furthermore, the specific surface area of yarn is increased to thus make raising property and processability poor, and the warp knit thus prepared is non-uniform in its raised fiber and is very inferior in appearance.

In case that the ultra fine denier fiber of 0.2 denier prepared by means of the bicomponent division type conjugate spinning process consisting of nylon/polyester is applied to a warp knit, warping property, knitting property and raising property of the warp knit are very poor since the nylon is seperated from the polyester by means of the tension and friction in warping and knitting because the nylon and the polyester are incompatible with each other. Furthermore, appearance of the prepared warp knit is very poor due to non-uniformity of raised fibers. Moreover, since the nylon and the polyester are mixed, the warp knit is difficult to dyestuffs and also its color fastness is low.

In case that a warp knit is prepared by the sea-island type conjugate fiber of 0.001˜0.3 denier prepared by using alkali easy soluble copolymerized polyester as a sea component and regular polyester as an island component by means of the bicomponent dissolution type spinning process, warping property, raising property and knitting property of the warp knit are good; however, the wash fastness and light fastness of the warp knit are low due to poor dyeing property which is characteristic of the polyester (island component).

Accordingly, it is an object of the present invention to prepare a knitted fabric having excellent wash fastness and light fastness, which may omit a dyeing process by knitting a knitted fabric using a sea-island type conjugate fiber, which contains a dope dyed component as a fiber forming component, as a face yarn and/or back yarn and then dissolving a sea component of the sea-island type conjugate fiber when producing a warp knit fabric or circular knit fabric.

SUMMARY OF THE INVENTION

The present invention provides a knitted fabric having excellent wash fastness and light fastness, and a process of preparing for the same, which has excellent processability such as warping and knitting processability.

To achieve the above object, the present invention provides a knitted fabric having excellent wash fastness and light fastness, which comprises a ultra fine yarn including a dope dyed component selected from the group, consisting of carbon black, pigments and dyestuffs on the face and/or back, wherein the knitted fabric has the wash fastness of more then 2˜3 and the light fastness of more than level 5.

In addition, the present invention provides a process of preparing a knitted fabric having excellent wash fastness and light fastness, wherein a sea-island type conjugate fiber consisting of a fiber forming component, which contains 0.1˜15% by weight of dope dyed component selected from the group consisting of carbon black, pigments and dyestuffs, and a dissolution component, which is a easy soluble polymer, is used as face yarn and/or back yarn.

The present invention will now be described in more detail.

The knitted fabric of the present invention includes both warp knit fabric and weft knit fabric.

Firstly, the knitted fabric of the present invention has a ultra fine yarn including a dope dyed component selected from the group consisting of carbon black, pigments and dyestuffs on the face and/or back. The above ultra fine yarn is formed by knitting a knitted fabric using a bicomponent dissolution type conjugate fiber, which has polyester containing a dope dyed component as a fiber forming component and easy soluble polymer as a dissolution component, as a face yarn and/or back yarn, and then dissolving the dissolution component in the subsequent process.

In other words, to improve the processability, the knitted fabric becomes ultra-fine after knitting and raising it using the bicomponent dissolution type conjugate fiber as a face yarn and/or back yarn, and then dissolving the dissolution component.

As the easy soluble polymer, copolymerized polyester with very excellent alkali dissolubility is most preferably used. For example, the blended composition consisting of (i) copolymerized polyester formed by the copolymerization of an ester unit of ethylene terephthalic acid as a main component, with an ester unit containing metal sulfonates and (ii) a polyethyleneglycol having a number average molecular weight of more than 8,000 is used as the easy soluble polymer. In addition, water-easy soluble polyvinyl alcohol or polystyrene or the like may be used as the easy soluble polymer. However, the polystyrene is disadvantageous in that the solvent used in dissolution causes environmental contamination.

Particularly, according to the present invention, when spinning the sea-island type conjugate fiber, a dope dyed component is added in the fiber forming component in order to improve wash fastness and light fastness of the knitted fabric. As the dope dyed component, more than one component is used from the group consisting of carbon black, pigments and dyestuffs. If the carbon black is solely used, the ultra fine yarn (island component) has a black color. In case that the ultra fine yarn is desired to have other colors different from black, types of pigments or dyestuffs should be properly selected.

For example, the dyestuffs include solvent dyestuffs (Eastwelt Co., Ltd.) such as Papilion Yellow S-4G, Papilion Red S-G, Papilion Blue S-GL, etc., and the pigments include BASF Corporation products such as Heliogen Blue D 7030, Paliogen Red L 3885, Paliotol Yellow D 1819 Heliogen, etc. By properly mixing these pigments and dyestuffs of RGB colors, a desired color can be obtained. Moreover, if the content of carbon black in the island component is adjusted to be less than 5% by weight, a knitted fabric with grey color can be produced. The dope dyed components include pigments of black color or dyestuffs of black color.

The dope dyed component content is 0.1˜15% by weight with respect to the weight of the fiber forming component (ultra fine yarn). If the dope dyed component content is less than 0.1% by weight, the improvement effect of wash fastness and light fastness is small, or if it is more than 15% by weight, the spinnability is decreased.

The knitted fabric of the present invention includes a warp knit fabric which consists of a face weave made of a ultra fine yarn including a dope dyed component and a back weave made of a high shrinkage yarn or synthetic fiber yarn, or which may have an intermediate weave made of a spandex elastic yarn between the face weave and the back weave.

Hereinafter, the warp knit fabric according to the present invention will be described in detail.

Preferably, the mono-filament fineness of the face weave yarn (ultra fine yarn) is 0.001˜0.3 denier. If the mono-filament fineness is more than 0.3 denier, the raising property and the durability of raised fiber are improved but the feeling of touch may become hard and a wirting effect may be decreased. If it is less than 0.001 denier, the softness can be increased but raised fiber easily fall out or are tangled due to friction, thus making the appearance poor.

Preferably, the high shrinkage yarn and synthetic fiber yarn (hereinafter, “back yarn”) includes polyester filaments. To improve wash fastness and Light fastness, the dope dyed component can be contained in 0.1˜15% by weight of the back yarn.

Preferably, the mono-filament fineness of the back yarn is 1˜5 denier. If the mono-filament fineness is less than 1 denier, it may be difficult to give proper repulsiveness to the warp knit fabric (finished fabric). If the mono-filament denier is more than 5 denier, processability such as warping and knitting processability can be worse, or the repulsiveness of the warp knit fabric becomes too large, for thereby making it difficult to exhibit softness of the face.

Preferably, the high shrinkage yarn includes copolymerized polyester. As the copolymer component, bisphenol-A, polyethylene glycol, isophthalic acid and the like can be used. However, the copolymer component of the present invention is not limited thereto.

Meanwhile, in a case that the spandex elastic yarn (hereinafter, “intermediate yarn”) is used as the yarn of the intermediate weave, the fiber density of the face weave can be much increased by the shrinkage of the intermediate weave. Since the spandex elastic yarn, which is the intermediate yarn, has a good elastic property, it increases the fiber density of the face weave of a finally finished fabric, thus improving the softness of the warp knit fabric and giving good elasticity and repulsiveness to the warp knit fabric. The total denier of spande)(is preferably 30˜90 denier.

In a knitting operation, the face yarn content is preferably 40˜87% by weight with respect to the total weight of a finished warp knit fabric. If it is less than 40% by weight, there is the risk of the warp knit fabric's softness being poor. If it is more than 87% by weight, the intermediate yarn content and the back yarn content become relatively low, thus drapery and mechanical physical properties become worse.

Meanwhile, the intermediate yarn content and the back yarn content are preferably 0˜20% and 13˜60% respectively by weight with respect to the total weight of the finished warp knit fabric. If it is over the above range, the softness of the warp knit fabric may be decreased. If it is under the above range, the shape stability and the drape property may be decreased.

The finished warp knit fabric is produced by raising, preheating, weight-reducing (removal of a dissolution component), buffing and finally heating the thusly knit fabric.

The present invention may omit a dyeing process because the ultra fine yarn contains the dope dyed component. To adjust the color of the warp knit fabric, however, an additional dyeing process may be carried out. In case of the additional dyeing process, the concentration of dyestuffs used is preferably less than 3% o.w.f. The density of the finished warp knit fabric is preferably 40˜60 loop/inch.

The warp knit fabric of the present invention has very excellent wash fastness and light fastness because the face yarn or both of the face yarn and the back yarn contain a black dope dyed component. More particularly, to get a desired color, no dyeing process is required, or, if any, only an additional dyeing process using 3.0% o.w.f of dyestuffs (based on a powdery dyestuffs) is required. Of course, even if the additional dyeing using more than 3.0% o.w.f of dyestuffs is required, this will be achieved only by increasing the dope dyed component content in the island component.

The additional dyeing is carried out mostly for the purpose of varying the color of the warp knit fabric into another color using a given dope dyed fiber as a base. The reason why the amount of dyestuffs used in the additional dyeing is limited to 3.0% o.w.f. of a powdery dyestuffs is because, if the amount of dyestuffs is more than the above value, the wash fastness and the light fastness are sharply decreased.

The wash fastness and the light fastness are in inverse proportion to an amount of dyestuffs used. In case of a ultra-fine yarn, the specific surface area is much higher than that of a general yarn, so its fastness is inevitably low. Nevertheless, in case of a liquid dyestuffs whose concentration is 50% or so, which is lower than that of a powdery dyestuffs, up to 6.0% o.w.f. can be used.

Therefore, the range of fastness of the dope dyed fiber to be achieved by the present invention is more than level 2˜3 in wash fastness and more than level 5.0 in light fastness.

In addition, the warp knit fabric of the present invention has excellent processability such as warping and knitting properties because the face yarn is a bicomponent dissolution type yarn. At the same time, in a subsequent process, since the dissolution component is dissolved to make the face yarn ultra fine, the warp knit fabric can exhibit excellent writing effect and softness.

Meanwhile, the warp knit fabric of the present invention can solve the problem that the feeling of touch becomes too soft when producing a warp knit fabric using a conventional bicomponent dissolution type yarn, because the back yarn is a thick-denier yarn with a proper denier. Moreover, it can exhibit excellent drapery. Particularly, in case that the intermediate weave is formed of a spandex elastic yarn with good elastic processability and the back weave is formed of a high shrinkage yarn, the density of the ultra fine yarn of the face weave becomes much higher and thereby the elongation recovery and softness of the warp knit fabric in the wale direction and course direction become more excellent.

The knitted fabric of the present invention also includes a weft knit fabric, which is composed of a ultra fine yarn including a dope dyed component or mixed filament yarn of the ultra fine yarn and a high shrinkage yarn at the face and/or back.

Hereinafter, the weft knit fabric of the present invention will be described in detail.

The boiling water shrinkage of a high shrinkage yarn used in producing the air textured filament yarn is preferably more than 15% in order to improve the softness of a final product. As a specific example of the high shrinkage yarn, polyester filaments and the like can be used.

In the case that the ultra fine yarn or a mixed filament yarn thereof is used for any one of the face and back, it is preferable to use a thick-denier yarn of polyester filaments as the yarn of the other side. To improve wash fastness and light fastness, the dope dyed component can be contained in 0.1˜15% by weight of thick-denier yarn.

Preferably, the mono-filament denier of the thick-denier yarn is 0.5˜5 denier. If the mono-filament denier is less than 0.5 denier, it may be difficult to give proper repulsiveness to the circular knit fabric. If the mono-filament denier is more than 5 denier, processability such as warping and knitting processability can be worse, or the repulsiveness of the weft knit fabric becomes too large, for thereby making it difficult to exhibit softness of the face.

The process of preparing the weft knit fabric according to the present invention will be described more specifically. Firstly, as the face yarn and the back yarn, a sea-island type conjugate fiber consisting of a fiber forming component, which contains 0.1˜15% by weight of dope dyed component selected from the group consisting of carbon black, pigments and dyestuffs, and a dissolution component, which is a easy soluble polymer, is used, or a mixed filament yarn of the sea-island type conjugate fiber and a high shrinkage yarn is used, thus knitting the weft knit fabric in a circular knitting machine.

Meanwhile, it is also possible to knit the circular knit fabric by using the sea-island type conjugate fiber or the mixed filament yarn of the sea-island type conjugate fiber and the high shrinkage yarn as either one of the face yarn or back yarn and using a polyester thick-denier yarn with mono-filament fineness of 0.5˜5 denier as the yarn of the other side.

Next, by the alkali weight reduction of the resultant circular knit fabric, the dissolution component (sea component) in the sea-island type conjugate fiber is dissolved to thus achieve a ultra-fine filament.

The circular knit fabric of the present invention contains the dope dyed component in the ultra-fine filament, so the dyeing process can be omitted. However, in order to adjust the color of the circular knit fabric, an additional dyeing can be performed. However, in order to adjust the color of the ultra-fine denier fabric, an additional dyeing can be performed. In the additional dyeing process, a sufficiently deep color can be obtained even at a concentration of dyestuffs less than 5%, and thusly the amount of the dyestuffs to be used can be reduced.

The ultra-fine filament or the mixture yarn of ultra-fine yarn and thick-denier yarn, which constitute the circular knit fabric of the present invention, contain a black dope dyed component, and thus their wash fastness and light fastness are very excellent. More particularly, the wash fastness is more than Level 2˜3, and the light fastness is more than level 5. Furthermore, the knitted fabric of the present invention has an excellent processability since it is knitted in the sea-island type conjugate fiber state, and at the same time it can achieve a good softness since yarn in the knitted fabric becomes ultra-fine as the dissolution component is dissolved in the subsequent process.

DETAILED DESCRIPTIION OF THE EMBODIMENTS

The present invention is now understood more specifically by comparison between examples of the present invention and comparative examples. However, the present invention is not limited to such examples. [0049]
—Production of Warp Knit Fabric—[0050]

EXAMPLE 1

A warp knit fabric with a density of 23 loops/cm is produced, wherein a dissolution type conjugate fiber (dope dyed yarn) is used as the face yarn, a spandex elastic yarn of 40 denier/5 filaments is used as the intermediate yarn and a polyester multi-filament (dope dyed yarn) of 50 denier/24 filaments containing 3% by weight of carbon black is used as the back yarn, the dissolution type conjugate fiber consisting of polyethylene terephthalate containing 4% by weight of carbon black as a fiber forming component and alkali easy soluble copolymerized polyester composed of 5 mole % of polyethleneglycol, 5 mole % of dimethyl-5-sulfoisothphalate, 5 mole % of isophthalic acid and 85 mole % of polyethylene terephthalate as a dissolution component, and having a fiber forming component denier of 0.07 after dissolving the dissolution component. At this time, in the warp knit fabric, the weight ratio of face yarn:intermediate yarn:back yarn is set to 55% by weight:10% by weight:35% by weight. The produced warp knit fabric is raised to be shrunken by 50%, then preset, and weight-reduced for 40 minutes in a NaOH solution having a concentration of 1% o.w.s 98C, buffed and finally set at 180° C., thus producing a finished warp knit fabric. At this time, no dyeing is preformed. The results of evaluation of the quality processability of the finished warp knit fabric are indicated in Table 1. [0051]

EXAMPLE 2

A warp knit fabric with a density of 23 loops/cm is produced, wherein a dissolution type conjugate fiber (dope dyed yarn) is used as the face yarn, a spandex elastic yarn of 40 denier/5 filaments is used as the intermediate yarn and a polyester multi-filament (non-dope dyed yarn) of 50 denier/24 filaments is used as the back yarn, the dissolution type conjugate fiber consisting of polyethylene terephthalate containing 3% by weight of carbon black as a fiber forming component and alkali easy soluble copolymerized polyester composed of 5 mole % of polyethleneglycol, 5 mole % of dimethyl-5-sulfoisothphalate, 5 mole % of isophthalic acid and 85 mole % of polyethylene terephthalate as a dissolution component, and having a fiber forming component denier of 0.07 after dissolving the dissolution component. At this time, in the warp knit fabric, the weight ratio of face yarn: intermediate yarn: back yarn is set to 55% by weight: 10% by weight: 35% by weight. The produced warp knit fabric is raised to be shrunken by 50%, then preset, and weight-reduced for 40 minutes in a NaOH solution having a concentration of 2% o.w.s and a temperature of 98° C., buffed and finally set at 180° C., thus producing a finished warp knit fabric. The above warp knit fabric is dyed with a black disperse dyestuffs (2% o.w.f. concentration) by a typical rapid dyeing machine for 45 minutes at 120° C. (pH=4.5), is washed and then is finally set at 160° C. The results of evaluation of the quality properties of the finished warp knit fabric thus dyed are indicated in Table 1. [0052]

EXAMPLE 3

A warp knit fabric with a density of 23 loops/cm is produced, wherein a dissolution type conjugate fiber (dope dyed yarn) is used as the face yarn, a spandex elastic yarn of 40 denier/5 filaments is used as the intermediate yarn and a polyester multi-filament (non-dope dyed yarn) of 50 denier/24 filaments is used as the back yarn, the dissolution type conjugate fiber consisting of polyethylene terephthalate containing 5% by weight of Papilion Yellow S-4G (products by Eastwell Co., Ltd.), which is a solvent dyestuffs, as a fiber forming component and alkali easy soluble copolymerized polyester composed of 5 mote % of polyethylene glycol, 5 mole % of dimethyl-5-sulfoisothphalate, 5 mole % of isophthalic acid and 85 mole % of polyethylene terephthalate as a dissolution component, and having a fiber forming component denier of 0.07 after dissolving the dissolution component. At this time, in the warp knit fabric, the weight ratio of face yarn: intermediate yarn:back yarn is set to 55% by weight: 10% by weight: 35% by weight. The produced warp knit fabric is raised to be shrunken by 50%, then preset, and weight-reduced for 40 minutes in a NaOH solution having a concentration of 1% o.w.s 98C, buffed and finally set at 180° C., thus producing a finished warp knit fabric. The results of evaluation of the quality properties of the finished warp knit fabric are indicated in Table 1. [0053]

EXAMPLE 4

A warp knit fabric with a density of 23 loops/cm is produced, wherein a dissolution type conjugate fiber (dope dyed yarn) is used as the face yarn, a spandex elastic yarn of 40 denier/5 filaments is used as the intermediate yarn and a high shrinkage polyester yarn (non-dope dyed yarn) of 50 denier/24 filaments is used as the back yarn, the dissolution type conjugate fiber consisting of polyethylene terephthalate containing 4% by weight of Heliogen Blue D 7030 (products by BASF.), which is a pigment, as a fiber forming component and alkali easy soluble copolymerized polyester composed of 5 mole % of polyethylene glycol, 5 mole % of dimethyl-5-sulfoisothphalate, 5 mole % of isophthalic acid and 85 mole % of polyethylene terephthalate as a dissolution component, and having a fiber forming component denier of 0.07 after dissolving the dissolution component. At this time, in the warp knit fabric, the weight ratio of face yarn: intermediate yarn:back yarn is set to 55% by weight: 10% by weight: 35% by weight. The produced warp knit fabric is raised to be shrunken by 50%, then preset, and weight-reduced for 40 minutes in a NaOH solution having a concentration of 1% o.w.s 98° C., buffed and finally set at 180° C., thus producing a finished warp knit fabric. The results of evaluation of the quality properties of the finished warp knit fabric are indicated in Table 1. [0054]

EXAMPLE 5

A warp knit fabric with a density of 23 loops/cm is produced, wherein a dissolution type conjugate fiber (dope dyed yarn) is used as the face yarn and a polyester multi-filament (dope dyed yarn) of 50 denier/24 filaments containing 3% by weight of carbon black is used as the back yarn, the dissolution type conjugate fiber consisting of polyethylene terephthalate containing 4% by weight of carbon black as a fiber forming component and alkali easy soluble copolymerized polyester composed of 5 mole % of polyethleneglycol, 5 mole % of dimethyl-5-sulfoisothphalate, 5 mole % of isophthalic acid and 85 mole % of polyethylene terephthalate as a dissolution component, and having a fiber forming component denier of 0.07 after dissolving the dissolution component. At this time, in the warp knit fabric, the weight ratio of face yarn:back yarn is set to 45% by weight: 55% by weight. The produced warp knit fabric is raised to be shrunken by 50%, then preset, and weight-reduced for 40 minutes in a NaOH solution having a concentration of 1% o.w.s 98° C., buffed and finally set at 180° C., thus producing a finished warp knit fabric. At this time, no dyeing process is performed. The results of evaluation of the quality properties of the finished warp knit fabric are indicated in Table 1. [0055]

EXAMPLE 6

A warp knit fabric with a density of 23 loops/cm is produced, wherein a dissolution type conjugate fiber (dope dyed yarn) is used as the face yarn and a polyester multi-filament (non-dope dyed yarn) of 50 denier/24 filaments is used as the back yarn, the dissolution type conjugate fiber consisting of polyethylene terephthalate containing 3% by weight of carbon black as a fiber forming component and alkali easy soluble copolymerized polyester composed of 5 mole % of polyethleneglycol, 5 mole % of dimethyl-5-sulfoisothphalate, 5 mole % of isophthalic acid and 85 mole % of polyethylene terephthalate as a dissolution component, and having a fiber forming component denier of 0.07 after dissolving the dissolution component. At this time, in the warp knit fabric, the weight ratio of face yarn: back yarn is set to 45% by weight: 55% by weight. The produced warp knit fabric is raised to be shrunken by 50%, then preset, and weight-reduced for 40 minutes in a NaOH solution having a concentration of 1% o.w.s 98° C., buffed and finally set at 180° C., thus producing a finished warp knit fabric. The above warp knit fabric is dyed with a black disperse dyestuffs (2% o.w.f. concentration) by a typical rapid dyeing machine for 45 minutes at 120° C. (pH=4.5), is washed and then is finally set at 160□. The results of evaluation of the quality properties of the finished warp knit fabric thus dyed are indicated in Table 1. [0056]

EXAMPLE 7

A warp knit fabric with a density of 23 loops/cm is produced, wherein a dissolution type conjugate fiber (dope dyed yarn) is used as the face yarn and a polyester multi-filament (non-dope dyed yarn) of 50 denier/24 filaments is used as the back yarn, the dissolution type conjugate fiber consisting of polyethylene terephthalate containing 5% by weight of Papilion Yellow S-4G (products by EastwelL Co., Ltd.), which is a solvent dyestuffs, as a fiber forming component and alkali easy soluble copolymerized polyester composed of 5 mole % of polyethylene glycol, 5 mole % of dimethyl-5-sulfoisothphalate, 5 mole % of isophthalic acid and 85 mole % of polyethylene terephthalate as a dissolution component, and having a fiber forming component denier of 0.07 after dissolving the dissolution component. At this time, in the warp knit fabric, the weight ratio of face yarn: back yarn is set to 45% by weight: 55% by weight. The produced warp knit fabric is raised to be shrunken by 50%, then preset, and weight-reduced for 40 minutes in a NaOH solution having a concentration of 1% o.w.s 98° C., buffed and finally set at 180° C., thus producing a finished warp knit fabric. The results of evaluation of the quality properties of the finished warp knit fabric are indicated in Table 1. [0057]

EXAMPLE 8

A warp knit fabric with a density of 23 loops/cm is produced, wherein a dissolution type conjugate fiber (dope dyed yarn) is used as the face yarn and a polyester multi-filament (non-dope dyed yarn) of 50 denier/24 filaments is used as the back yarn, the dissolution type conjugate fiber consisting of polyethylene terephthatate containing 4% by weight of Heliogen Blue D 7030 (products by BASF.), which is a pigment, as a fiber forming component and alkali easy soluble copolymerized polyester composed of 5 mole % of polyethylene glycol, 5 mole % of dimethyl-5-sulfoisothphalate, 5 mole % of isophthalic acid and 85 mole % of polyethylene terephthalate as a dissolution component, and having a fiber forming component denier of 0.07 after dissolving the dissolution component. At this time, in the warp knit fabric, the weight ratio of face yarn:back yarn is set to 45% by weight: 55% by weight. The produced warp knit fabric is raised to be shrunken by 50%, then preset, and weight-reduced for 40 minutes in a NaOH solution having a concentration of 1% o.w.s 98° C., buffed and finally set at 180° C., thus producing a finished warp knit fabric. The results of evaluation of the quality properties of the finished warp knit fabric are indicated in Table 1. [0058]

COMPARATIVE EXAMPLE 1

A warp knit fabric with a density of 23 Loops/cm is produced, wherein a dissolution type conjugate fiber (non-dope dyed yarn) is used as the face yarn and a polyester multi-filament (non-dope dyed yarn) of 50 denier/24 filaments is used as the back yarn, the dissolution type conjugate fiber consisting of polyethylene terephthalate as a fiber forming component and alkali easy soluble copolymerized polyester composed of 5 mole % of polyethleneglycol, 5 mole % of dimethyl-5-sulfoisothphalate, 5 mole % of isophthalic acid and 85 mole % of polyethylene terephthalate as a dissolution component, and having a fiber forming component denier of 0.07 after dissolving the dissolution component. At this time, in the warp knit fabric, the weight ratio of face yarn: back yarn is set to 45% by weight: 55% by weight. The produced warp knit fabric is raised to be shrunken by 50%, then preset, and weight-reduced for 40 minutes in a NaOH solution having a concentration of 1% o.w.s 98° C., buffed and finally set at 180° C., thus producing a finished warp knit fabric. The above warp knit fabric is dyed with a black disperse dyestuffs (12.5% o.w.f. concentration) by a typical rapid dyeing machine for 45 minutes at 120° C. (pH=4.5). The results of evaluation of the quality properties of the finished warp knit fabric are indicated in Table 1. [0059]

COMPARATIVE EXAMPLE 2

A warp knit fabric with a density of 23 Loops/cm is produced, wherein a dissolution type conjugate fiber (non-dope dyed yarn) is used as the face yarn, a spandex elastic yarn of 40 denier/5 filaments is used as the intermediate yarn and a polyester multi-filament (non-dope dyed yarn) of 50 denier/24 filaments is used as the back yarn, the dissolution type conjugate fiber consisting of polyethylene terephthalate as a fiber forming component and alkali easy soluble copolymerized polyester composed of 5 mole % of polyethleneglycol, 5 mole % of dimethyl-5-sulfoisothphalate, 5 mole % of isophthalic acid and 85 mole % of polyethylene terephthatate as a dissolution component, and having a fiber forming component denier of 0.07 after dissolving the dissolution component. At this time, in the warp knit fabric, the weight ratio of face yarn:intermediate yarn:back yarn is set to 55% by weight: 10% by weight:35% by weight. The produced warp knit fabric is raised to be shrunken by 50%, then preset, and weight-reduced for 40 minutes in a NaOH solution having a concentration of 1% o.w.s 98° C., buffed and finally set at 180° C., thus producing a finished warp knit fabric. The above warp knit fabric is dyed with a black disperse dyestuffs (12.5% o.w.f. concentration) by a typical rapid dyeing machine for 45 minutes at 120° C. (pH=4.5). The results of evaluation of the quality properties of the finished warp knit fabric are indicated in Table 1.

TABLE 1


Processability and Warp Knit Fabric Properties

Warp Knit Fabric Processability

Processability

Wash

Touch

Class	Warping	Knitting	Fastness	Light Fastness	(Softness)	Repulsiveness

Example 1	⊚	⊚	Level 5	Level 7	⊚	⊚
Example 2	⊚	⊚	Level 3	Level 6	⊚	⊚
Example 3	⊚	⊚	Level 4	Level 7	⊚	⊚
Example 4	⊚	⊚	Level 4	Level 7	⊚	⊚
Example 5	⊚	⊚	Level 5	Level 7	⊚	⊚
Example 6	⊚	⊚	Level 3	Level 6	⊚	⊚
Example 7	⊚	⊚	Level 4	Level 7	⊚	⊚
Example 8	⊚	⊚	Level 4	Level 7	⊚	⊚
Comparative	⊚	⊚	Level 1	Level 3	⊚	Δ
Example 1
Comparative	⊚	⊚	Level 1	Level 3	⊚	Δ
Example 2

—Production of Weft Knit Fabric—[0061]

EXAMPLE 9

A circular knit fabric is knitted on an interlock circular knitting machine with 18 dial gauges-4 races, wherein a mixed filament yarn made of a dissolution type conjugate fiber (dope dyed yarn) of 150 denier/48 filaments and a high shrinkage polyester yarn of 30 denier/12 filaments having a boiling water shrinkage rate of 18% is fed as the face yarn and a polyester filament (dope dyed yarn) of 50 denier/24 filaments containing 3% by weight of carbon black is fed as the back yarn, the dissolution type conjugate fiber consisting of polyethylene terephthalate containing 3% by weight of carbon black as a fiber forming component and alkali easy soluble copolymerized polyester composed of 5 mole % of polyethylene glycol, 5 mole % of dimethyl-5-sulfoisothphalate, 5 mole % of isophthalic acid and 85 mote % of polyethylene terephthatate as a dissolution component, and having a fiber forming component denier of 0.06 after dissolving the dissolution component. The knitted circular knit fabric is treated in a NaOH solution having a concentration of 1% o.w.s 98° C. and is raised, thus producing a finished circular knit fabric. At this time, no dyeing process is performed. The results of evaluation of the quality propeties of the finished circular knit fabric are indicated in Table 2. [0062]

EXAMPLE 10

The finished circular knit fabric prepared in the same process and conditions as in Example 9 is dyed with a black disperse dyestuffs (1.0% o.w.f. concentration) by a typical rapid dyeing machine for 45 minutes at 120° C. (pH=4.5), is washed and then is finally set at 160° C. The results of evaluation of the quality processability of the finished circular knit fabric thus dyed are indicated in Table 2. [0063]

EXAMPLE 11

A circular knit fabric is knitted on an interlock circular knitting machine with 18 dial gauges-4 races, wherein a mixed filament yarn made of a dissolution type conjugate fiber (dope dyed yarn) of 150 denier/48 filaments and a high shrinkage polyester yarn of 30 denier/12 filaments having a boiling water shrinkage of 18% is fed as the face yarn and a polyester filament (non-dope dyed yarn) of 50 denier/24 filaments is fed as the back yarn, the dissolution type conjugate fiber consisting of polyethylene terephthalate containing 5% by weight of Papition Yellow S-4G (products by Eastwell Co., Ltd.), which is a solvent dyestuffs, as a fiber forming component and alkali easy soluble copolymerized polyester composed of 5 mote % of polyethylene glycol, 5 mole % of dimethyl-5-sulfoisothphatate, 5 mote % of isophthalic acid and 85 mole % of polyethylene terephthalate as a dissolution component, and having a fiber forming component denier of 0.06 after dissolving the dissolution component. The knitted circular knit fabric is treated in a NaOH solution having a concentration of 1% o.w.s 98° C. and is raised, thus producing a finished circular knit fabric. The results of evaluation of the quality properties of the finished circular knit fabric are indicated in Table 2. [0064]

EXAMPLE 12

A circular knit fabric is knitted on an interlock circular knitting machine with 18 dial gauges-4 races, wherein a dissolution type conjugate fiber (dope dyed yarn) of 150 denier/48 filaments is fed as the face yarn and a polyester filament (non-dope dyed yarn) of 50 denier/24 filaments is fed as the back yarn, the dissolution type conjugate fiber consisting of polyethylene terephthalate containing 4% by weight of Heliogen Blue D 7030 (products by BASF.), which is a pigment, as a fiber forming component and alkali easy soluble copolymerized polyester composed of 5 mole % of polyethylene glycol, 5 mole % of dimethyl-5-sulfoisothphalate, 5 mole % of isophthalic acid and 85 mole % of polyethylene terephthalate as a dissolution component, and having a fiber forming component denier of 0.06 after dissolving the dissolution component. The knitted circular knit fabric is treated in a NaOH solution having a concentration of 1% o.w.s 98° C. and is raised, thus producing a finished circular knit fabric. The results of evaluation of the quality properties of the finished circular knit fabric are indicated in Table 2. [0065]

COMPARATIVE EXAMPLE 3

A circular knit fabric is knitted on an interlock circular knitting machine with 18 dial gauges-4 races, wherein an air textured filament yarn made of a dissolution type conjugate fiber (non-dope dyed yarn) of 150 denier/48 filaments and a high shrinkage polyester yarn of 30 denier/12 filaments having a boiling water shrinkage of 18% is fed as the face yarn and a polyester filament (non-dope dyed yarn) of 50 denier/24 filaments is fed as the back yarn, the dissolution type conjugate fiber consisting of polyethylene terephthalate as a fiber forming component and alkali easy soluble copolymerized polyester composed of 5 mole % of polyethylene glycol, 5 mole % of dimethyl-5-sulfoisothphalate, 5 mole % of isophthatic acid and 85 mote % of polyethylene terephthalate as a dissolution component, and having a fiber forming component denier of 0.06 after dissolving the dissolution component. The knitted circular knit fabric is treated in a NaOH solution having a concentration of 1% o.w.s 98° C., is raised and then is dyed with a black disperse dyestuffs (12.5% o.w.f. concentration) by a typical rapid dyeing machine for 45 minutes at 120° C. (pH=4.5), thus producing a finished circular knit fabric. The results of evaluation of the quality properties of the finished circular knit fabric are indicated in Table 2.

TABLE 2


Quality Properties of weft Knit Fabric

Quality Properties of weft Knit Fabric

			Blackness
	Washing		Before	Blackness After
class	Fastness	Light Fastness	Dyeing	Dyeing

Example 9	Level 5	Level 7	14.3	—
Example 10	Level 3-4	Level 6	14.3	13.4
Example 11	Level 4-5	Level 6	—	—
Example 12	Level 4-5	Level 6	—	—
Comparative	Level 1	Level 3	—	14.3
Example 3

In the present invention, the quality properites of knitted fabrics were evaluated by the following methods. [0067]
Wash Fastness [0068]
This was evaluated by the KS K 0430 A1 method. [0069]
Light Fastness [0070]
This was evaluated by the KS K 0700 method. [0071]
Surface Softness [0072]
An organoleptic test was carried out by 10 panellers. When 8 members or more judged that the sample was soft, the fabric was evaluated to be good (⊚), when 5 to 7 members judged as above, the fabric was evaluated to be average (Δ), and when 8 members or more judged that the fabric was deficient in the softness, the fabric was evaluated to be poor (x). [0073]
Repulsiveness [0074]
An organoleptic test was carried out by 10 panellers. When 8 members or more judged that the sample has repulsiveness, the fabric was evaluated to be good (⊚), when 5 to 7 members judged as above, the fabric was evaluated to be average (Δ), and when 8 members or more judged that the fabric was deficient in the repulsiveness, the fabric was evaluated to be poor (x). [0075]
Warping Processability [0076]
Warping processability is evaluated by checking the stop times/hour of warping machine due to yarn defect at a warping speed of 500 m/min. if the stop times/hour is naught, it is excellent (⊚). If the stop times/hour is one or two, it is ordinary (Δ). If the stop times/hour is more than 3 times, it is poor (x). The stop times/hour of warping machine is calculated by dividing the total stop times of warping machine in warping the yarn of 9 kg into total warping time. [0077]
Knitting Processability [0078]
Knitting processability is evaluated by checking the stop times/hour of knitting machine due to yarn defect at knitting speed of 1000 m/min. If the stop times/hour is naught, it is excellent (⊚). If the stop times/hour is one or two, it is ordinary (Δ). If the stop times/hour is more than 3 times, it is poor (x). The stop times/hour of knitting machine is calculated by dividing the total stop times of knitting machine in a day into 24 hour. [0079]
Blackness (L Value) [0080]
This was evaluated by using Spectra Flash 600 of Data Color Company. [0081]
Boiling Water Shrinkage (%) [0082]
A sample fiber is prepared and the original Length (l[0083] ₀) is measured. Then, the sample fiber is treated in boiling water of 100° C. for 15 minutes. Then, the sample length (l₁) is measured under a load of 0.15 g/d. The boiling water shrinkage is calculated according to the following formula $Boiling Water Shrinkage (%) = \frac{l_{0} - l_{1}}{l_{0}} \times 100$

INDUSTRIAL APPLICABILITY

As described above, the knitted fabric according to the present invention may not be dyed and has excellent wash fastness and light fastness since the ultra fine yarn constituting the knitted fabric contains the dope dyed component. Furthermore, the knitted fabric is warped and knitted using a sea-island type conjugate fiber, the processability is good and the touch and repulsiveness are excellent because the knitted fabric becomes ultra-fine after dissolving the sea component. As the result, the knitted fabric of the present invention is useful for materials of artificial leathers or ladies clothes. [0084]

Claims

What is claimed is:

1. A knitted fabric having excellent wash fastness and light fastness, comprising a ultra fine yarn including a dope dyed component selected from the group consisting of carbon black, pigments and dyestuffs on the face and/or back, wherein the knitted fabric has the wash fastness of more than level 2˜3 and the light fastness of more than level 5.

2. The knitted fabric of claim 1, wherein the dope dyed component content in the ultra fine yarn is 0.1˜15% by weight.

3. The knitted fabric of claim 1, wherein the mono-filament fineness of the ultra fine yarn is 0.001˜0.3 denier.

4. The knitted fabric of claim 1, wherein the dope dyed component includes pigments of black color or dyestuffs of black color.

5. The knitted fabric of claim 1, wherein the knitted fabric is a warp knit fabric which consists of a face weave made of a ultra fine yarn including a dope dyed component and a back weave made of a high shrinkage yarn or synthetic fiber yarn.

6. The knitted fabric of claim 1, wherein the knitted fabric is a warp knit fabric which consists of a face weave made of a ultra fine yarn including a dope dyed component, a back weave made of a high shrinkage yarn or synthetic fiber yarn, and an intermediate weave made of a spandex elastic yarn.

7. The knitted fabric of claim 5 or 6, wherein the high shrinkage yarn or synthetic fiber yarn constituting the back weave contains a dope dyed component selected from the group consisting of carbon black, pigments and dyestuffs.

8. The knitted fabric of claim 5 or 6, wherein the mono-filament fineness of the high shrinkage yarn or synthetic fiber yarn constituting the back weave is 1˜5 denier.

9. The knitted fabric of claim 5 or 6, wherein the ultra fine yarn, shrinkage yarn and synthetic fiber yarn are mainly composed of polyester.

10. The knitted fabric of claim 1, wherein the knitted fabric is a circular knit fabric whose face weave and/or back weave are made of a ultra fine yarn including a dope dyed component or a mixed filament yarn of the ultra fine yarn and a high shrinkage yarn.

11. The knitted fabric of claim 10, wherein the high shrinkage yarn includes the dope dyed component.

12. The knitted fabric of claim 10, wherein the ultra fine yarn and the high shrinkage yarn are mainly composed of polyester.

13. The knitted fabric of claim 5, 6 or 10, wherein the boiling water shrinkage rate of the high shrinkage yarn is 15% or more.

14. A process of preparing a knitted fabric having excellent wash fastness and Light fastness, wherein a sea-island type conjugate fiber consisting of a fiber forming component, which contains a dope dyed component 0.1˜15% by weight selected from the group consisting of carbon black, pigments and dyestuffs, and a dissolution component, which is a easy soluble polymer, is used as face yarn and/or back yarn.

15. The process of claim 14, wherein the knitted fabric is additionally dyed with a dyestuffs having a concentration of 3.0% o.w.f. (based on powdery dyestuffs).

16. The process of claim 14, wherein the mono-filament denier of the fiber forming component in the sea-island type conjugate fiber is 0.001˜0.3 denier.

17. The process of claim 14, wherein the sea-island type conjugate fiber is used as the face yarn and a high shrinkage yarn or synthetic fiber yarn is used as the back yarn.

18. The process of claim 14, wherein the sea-island type conjugate fiber is used as the face yarn, a high shrinkage yarn or synthetic fiber yarn is used as the back yarn and a spandex elastic yarn is used as an intermediate yarn.

19. The process of claim 17 or 13, wherein the mono-filament fineness of the back yarn is 1˜5 denier.

20. The process of claim 17 or 18, wherein the face yarn and back yarn is mainly composed of polyester.