WO2004079062A1

WO2004079062A1 - A sea-island type composite fiber with excellent color strength, and its suede like fabrics

Info

Publication number: WO2004079062A1
Application number: PCT/KR2004/000441
Authority: WO
Inventors: Young-Hwan Lee; Yoeng-Baeg Choi; Gil-Sook Jeong
Original assignee: Kolon Industries Inc
Priority date: 2003-03-05
Filing date: 2004-03-02
Publication date: 2004-09-16
Also published as: KR20040078802A; RU2005130977A; RU2305145C2; CN1327051C; KR100624145B1; UA78440C2; CN1756863A; TR200503551T2

Abstract

A conventional sea-island type composite fiber and its suede-like fabrics have poor color strength, and thus have problems such as an increase of a manufacturing cost and environmental contamination since they require a long time dyeing at a high concentration upon making the suede-like, fabrics. Further, they have a problem that the washing fastness and light fastness are low due to the use of a large amount of a dye. The present invention provides a sea-island type composite fiber, which has excellent color strength by containing a specific diol comonomer in island component, and its suede-like fabrics.

Description

A SEA-ISLAND TYPE COMPOSITE FIBER WITH EXCELLENT COLOR

STRENGTH, AND ITS SUEDE LIKE FABRICS

TECHNICAL FIELD The present invention relates to a sea-island type composite fiber with excellent color strength and its suede-like fabrics. More particularly, the present invention relates to a sea-island type composite fiber which is excellent in color strength (dyeing property) by containing comonomers in an island component and its suede-like fabrics which contain some or all parts of the yarn constituting the same.

With the recent trend of a higher level of market demand requiring a higher grade and with the spread of an understanding of animal protection, the production amount and use amount of a suede-like fabrics made from sea-island type composite fiber is growing bigger every day, and its uses are also becoming various.

Suede was originally made by finishing animals' leather and has been used for a high-grade glove, women's shoe, etc. However, natural suede was unable to be produced in large quantities since its source of supply is animals and thus their number of individuals is restricted, and gave rise to ill effects such as environmental pollution due to slaughter.

Further, suede was such a material that was difficult to become popular due to its very high price because high expenses incurred in the above production procedure had to be applied to the price of a product as it were. Such natural suede has a demerit that it is very difficult to maintain in case of being applied for clothing because it is hard to be washed with water even if it was supplied in large quantities.

However, the development of synthetic fibers has marked a turning point that remarkably complements this demerit of

natural suede. That is, with the development of synthetic fibers, it has been made possible to produce suede-like products at a lower cost.

Suede-like products using synthetic fibers are capable of mass production, cause less pollution, don't need to slaughter animals, are easy to handle since they are washable with water, and are able to express various colors.

Such suede-like products using synthetic fibers are being widely adapted to a variety of furniture and sofas and interior products, such as curtains, etc. as well as to clothing. Recently, there is a tendency that they are also adapted to car sheets since their dyeing property and color fastness are much improved. Especially, suede-like clothing are recently being adapted for use in innerwear as well as for exiting use in jumper, coat, etc.

Such suede-like woven or knitted fabrics products using

synthetic fibers (hereinafter, referred to as 'suede-like fabrics')

can be produced by using directly melt-spun filaments of small

fineness, separable type composite fibers or sea-island type

composite fibers. But, the suede-like products has the

characteristic that naps of small thickness are raised on the

surfaces, so it is most preferable to produce suede-like

products by using sea-island type composite fibers so as to

exhibit this characteristic more effectively.

BACKGROUND ART

However, a sea-island type composite fiber has a disadvantage that it is low in color strength. That is, even if dyed with a dye of the same quantity, a sea-island type composite fiber having a very large surface area is dyed in a much lighter color than Chemical Structural fibers. A polyester-based sea-island type composite fiber also shows such a disadvantage. To overcome this disadvantage, conventionally used is a method of dyeing an artificial suede-like fabrics made from a sea-island type composite fiber in a dyeing bath of high concentration for a long time.

However, such dyeing method has a disadvantage that the use amount of a dye is increased much to cause an increase of a product cost, and at the same time has another disadvantage that the possibility of environmental pollution becomes bigger. Further, due to the use of a large quantity of a dye, the color fastness to washing and light of a final product is deteriorated. Additionally, to overcome the disadvantage of a sea-island type composite fiber which is low in color strength when dyed, a method of introducing a pigment such as carbon black into an island component of the sea-island type composite fiber is carried out. In this case, additional equipment including a side feeder, etc. is required, and a master batch is produced for a separate use, which makes the process complicated. Further, there is another disadvantage that, in case that the diameter of an island component is similar to the diameter of the pigment or smaller than the diameter of the pigment, it is impossible to introduce the pigment into the island component.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects, and advantages of preferred embodiments of the present invention will be more fully described in the following detailed description, taken accompanying drawings. In the drawings:

Fig. 1 is a scanning electron microscope photograph showing a sectional state of a sea-island type composite fiber according to the present invention;

Fig. 2 is a scanning electron microscope photograph showing a sectional state of a suede-like fabrics made from the sea-island composite fiber (drawn yarn) according to the present invention; and Fig. 3 is a scanning electron microscope photograph showing a surface state of the suede-like fabrics made from the sea-island composite fiber (drawn yarn) according to the present invention.

DISCLOSURE OF THE INVENTION

The present invention provides a sea-island type composite fiber which has excellent color strength without an excessive increase in shrinkage by properly modifying a fiber forming ability resin constituting the island component of the sea-island type composite fiber. More concretely, the present invention provides a polyester sea-island type composite fiber which has a color strength improvement factor of more than

10%, a weight reduction rate difference of less than 10% and a shrinkage at boiling water (of a drawn yarn) of 5 to 15% in comparison with a conventional sea-island type composite fiber.

Additionally, the present invention provides a suede-like fabrics which has excellent color strength by using the sea-island type composite fiber with excellent color strength as some or all parts of yarn for woven or knitted fabrics.

To achieve the above objects, there is provided a sea-island type composite fiber with excellent color strength according to the present invention, which comprises an island component mainly composed of polyethylene terephthalate and having a monofilament fineness of 0.001 to 0.5 denier and a sea component composed of a copolymer polyester readily soluble to alkali, wherein the island component has a diol comonomer of Chemical structural Formula (I) and/ or a diol comonomer of Chemical Structural Formula (II) contained therein:

HO CH2 C — CH2 OH (I)

R2

HO CHz X CH2 OH (I I)

[wherein Ri and R2 are an alkyl group with 1 to 3 carbon atoms and X is an aliphatic ring with 5 to 8 carbon atoms.] Additionally, there is provided a suede-like fabrics according to the present invention, wherein some or all parts of yarn constituting the suede-like fabrics are ultrafine yarn of a monofilament fineness of 0.001 to 0.5 denier having a diol comonomer of Chemical Structural Formula (I) and/ or a diol comonomer of Chemical Structural Formula (II) contained in polyethylene terephthalate as a main component:

Hereinafter, the present invention will be described in detail. Firstly, a sea-island type composite fiber of the present invention is composed of a fiber forming ability resin as an island component and a resin readily soluble to alkali as a sea component. But, the present invention is characterized in that the island component resin is modified in order to improve the color strength of the sea-island type composite fiber.

More concretely, the island component of the present invention has a diol comonomer of Chemical Structural Formula (I) and/ or a diol comonomer of Chemical Structural Formula (II) copolymerized (contained) in polyethylene terephthalate as a main component.

HO CH2 C CH2 OH (I)

R2

HO — CH2 X CH2 OH (I I)

[wherein Ri and R2 are an alkyl group with 1 to 3 carbon atoms and X is an aliphatic ring with 5 to 8 carbon atoms.] In a case that the diol comonomers of Chemical

Structural Formula (I) and Chemical Structural Formula (II) are contained together in the island component, the content of the diol comonomer of Chemical Structural Formula (I) is preferably 0.5 to 10mol% with respect to the entire island component resin, more preferably 0.5 to 3.0mol% thereof. The content of the diol comonomer is 1.0 to 6.0mol% with respect to ethylene glycol alone.

If the content of the diole comonomer is greater than 10mol%, the shrinkage of a drawn sea-island type composite fiber increases too much, thereby deteriorating the soft touch and appearance of a final product. If less than 0.5mol% , the excellent color strength effect may be insufficient upon dyeing. The content of the diol comonomer of Chemical Structural Formula (II) is preferably 0.5 to 15mol% with respect to the entire island component resin, more preferably 0.5 to 5ol% thereof. The content of the diol comonomer is 1.0 to 10mol% with respect to ethylene glycol alone.

If the content of the diol comonomer is greater than 5 15mol%, the shrinkage of a drawn sea-island type composite fiber increases too much, thereby failing in exhibiting the unique touch and appearance of the suede-like fabrics. If less than 0.5mol%, the excellent color strength effect may be insufficient upon dyeing.

10 Meanwhile, if only the diol comonomer of Chemical

Structural Formula (I) or only the diol comonomer of Chemical Structural Formula (II) are contained in the island component, the content of diol comonomer of Chemical Structural Formula (I) or of Chemical Structural Formula (II) is preferably 1 to

1.5 20mol%. If greater than 20mol%, the unique touch and appearance of the suede-like fabrics may be deteriorated due to an increase in shrinkage of the fiber. If less than l mol%, the excellent color strength effect may be insufficient upon dyeing.

As a diol copolymer of Chemical Structural Formula (I) ,

20 can be used neo-pentylglycol, 2 ,2-diethyl- l ,3-propanediol, 2,2-ethylemethyl- l ,3-propanediol or the like. As a diol copolymer of Chemical Structural Formula (II) , can be used

1 ,4-cyclohexanedimethanol, 1 ,3-cyclopentanedimethanol, 1 ,5-cycloheptanedimethanol or the like.

The island component of the present invention is made by copolymerizing the diol copolymers and the comonomers used for polyethylene terephthalate polymerization, that is, ethylene glycol (EG) and terephthalic acid (TPA) , and the monofilament fineness of the island component is 0.001 to 0.5 denier. If the monofilament fineness is greater than 0.5 denier, the touch and appearance of a final product is deteriorated. If less than 0.001 denier, this makes the production of yarn and the dissolution of the sea component difficult.

The sea component of the present invention is preferably a copolymer polyester having an ionic character, which is readily soluble or readily decomposable to an alkali solution, such as sodium hydroxide. The sea-island type composite fiber of the present invention can be produced by conjugated spinning the above-explained island component and sea component using a typical sea-island type conjugated spinning apparatus and then drawing and taking up the same. The weight ratio of the island component to the sea component is preferably 70 : 30 by weight, but the present invention does not specifically limit the weight ratio thereof.

The sea-island type composite fiber of the present invention has a color strength improvement factor of more than 10% defined or evaluated as described later, a weight reduction rate difference of less than 10% and a shrinkage at boiling water of 5 to 15% in a drawn state. The melting point of the island component remaining after the dissolution of the sea component is 220 to 240°C.

The sea-island type composite fiber of the present invention has such a structure in which a chain of island component resin is bulky since a diol comonomer of Chemical Structural Formula (I) and/or a diol comonomer of Chemical Structural Formula (II) is contained (copolymerized) in the island component. Thus, the fiber is dyed in a much heavy color than conventional composite fibers under the same dyeing condition including the same dye. A suede-like fabrics of the present invention can be manufactured by making a woven fabrics using the sea-island type composite fiber of the present invention as some or all parts of the warp and weft or knitting a knitted fabrics using the sea-island type composite fiber of the present invention as some or all parts of file yarn, then dissolving and removing the sea component in the fabrics by treating the fabrics with an alkali aqueous solution, then dyeing the same and then raising or buffing it. The thusly manufactured suede-like fabrics of the present invention includes an ultrafine yarn of a monofilament fineness of 5 denier that has as some or all parts of the constituent yarn a diol comonomer of the following Chemical Structural Formula (I) and/ or a diol comonomer of the following Chemical Structural Formula (II) contained in polyethylene terephthalate as a main component. Ri

HO CH2 C CH2 OH (I)

R2

HO CH2 X CHz OH (I I)

[wherein Ri and R2 are an alkyl group with 1 to 3 carbon atoms and X is an aliphatic ring with 5 to 8 carbon atoms. ]

The suede-like fabrics of the present invention includes a woven fabrics, a warp knit fabrics, a loop knit fabrics or the like. In the present invention, various physical properties of the sea-island type composite fiber were evaluated or measured by the present invention as below. Color Strength Improvement Factor (Color Strength)

The color strength is evaluated by a color strength improvement factor. Firstly, a conventional sea-island type composite fiber, which is polyethylene terephthalate with the island component unmodified, and the sea-island type composite fiber of the present invention are treated with a sodium hydroxide aqueous solution, respectively, to dissolve and remove the sea component in the composite fiber and separate and extract only the island component. The island component (hereinafter, 'island component A') of the conventional sea-island type composite fiber and the island component (hereinafter, 'island component B') of the sea-island type composite fiber of the present invention, both extracted as above, are dyed respectively in a each dyeing bath for 30 minutes at 130°C with TERASIL BLACK MAW, a mixed dye manufactured by Ciba Specialty Chemical, having a concentration of 1 to 8% by weight relative to a dyeing target, then the dyed island components are dried for 24 hours at a room temperature, and then the K/ S value of island component A and the K/ S value of component B at a 600nm wavelength are obtained by a Spectraflash 600 computer color matching (CCM) colorimeter manufactured by Data Color Instrument Company.

Next, the obtained K/ S value of island component A and K/ S value of island component B are substituted into the following

formula to calculate the color strength improvement factor.

Each of the K/ S values is a value measured 10 times and

averaged.

Color Strength Improvement Factor (%) —

K/S Value of Island Component B — K/S Value of Component A _γ , _m K/S Value of Island Component A ^ιυυ

^• Boil-off Shrinkage %)

A sample hank is prepared by leaving a sea-island type

composite fiber (sample) at a room temperature for more than

one hour and then taking up it on a denier creel 10 times under a tensile force of indicated fineness * l / 10g. An initial load of indicated fineness ^χ 1 / 25g and a static load of indicated fineness>< 2g are applied to the prepared sample hank and the

length (Lo) at this time is measured. Next, the sample hank is heat treated for 15 minutes in the water of 100°C , dewatered

with an absorbent paper, left and dried indoors for 12 hours . Then, an initial load of indicated fineness ^χ l / 25g and a static load of indicated fineness ^χ 2g are applied again and the length (Li) at this time is measured. The measured Lo value and Li value are substituted into the following formula to calculate

the boil-off shrinkage . Boi l-off Shrinkage (%) = --J ° ^l x ifjfj

^• Melting Point(°C) of Island Component

The melting point of the island component with the sea component removed is measured by using a differential scanning calorimetry (DSC) . It should be noted that a temperature range is from a room temperature to 280°C and a temperature rising rate is 20°C per minute. The weight of the sample is 0.5mg ± 0.2mg.

^• Weight Reduction Rate Difference (%)

10 to 15g of the island component is separated and extracted from a conventional sea-island type composite fiber composed of polyethylene terephthalate with the island component unmodified, then the extracted island component (hereinafter, 'island component A') is weight-reduced by immersing it in 1% by weight of a sodium hydroxide aqueous solution with a liquid ratio of 50 and a temperature of 95°C for 60 minutes, and then the weight W2 of island component A is measured after weight reduction. The weight Wi of island component A before weight reduction and the weight W2 of island component A after weight reduction are substituted into the following formula to calculate the weigh reduction rate of island component A.

Weight Reduction Rate of Island Component A (%) =

x lOO i

Next, 10 to 15g of the island component is separated and extracted from the sea-island type composite fiber of the present invention, then the extracted island component (hereinafter, 'island component B') is weight-reduced by immersing it in 1 % by weight of a sodium hydroxide aqueous solution with a liquid ratio of 50 and a temperature of 95°C for 60 minutes, and then the weight W4 of island component B is measured after weight reduction. The weight W3 of island component B before weight reduction and the weight W₄ of island component B after weight reduction are substituted into the following formula to calculate the weigh reduction rate of island component B.

Weight Reduction Rate of Island Component B (%) = — ~ W —3 - x lOO

The calculated weight reduction rates of island component A and island component B are substituted into the following formula to calculate a weight reduction rate difference. Weight Reduction Rate Difference

Weight Reduction Rate of Island Component B —Weight Reduction Rate of Island Component A ,_m Weight Reduction Rate of Island Component A ^iuυ

ADVANAGEQUS EFFECT

The sea-island type composite fiber of the present invention is provided with excellent color strength even without an excessive increase in shrinkage since a fiber forming ability resin constituting the island component is modified into diol comonomers, and thus can express a heavy color which is difficult for a conventional polyester sea-island type composite fiber to express. Accordingly, the problems, such as an increase of a manufacturing cost due to an excessive use of a dye upon dyeing, an environmental contamination, washing fastness, light fastness, etc. , can be solved. Also , the color strength of a final product can be drastically improved upon manufacturing a suede-like fabrics.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention is now understood more concretely by comparison between examples of the present invention and comparative examples. However, the present invention is not limited to such examples. Example 1

By using as a sea component an ionic copolymer

polyester dissolvable with a sodium hydroxide aqueous

solution and as an island component a copolymer polyester

having l mol% of neo-penthylglycol and 2mol% of

1 ,4-cyclohexanedimethanol copolymerized (contained) in polyethylene terephthalate as a main component, a sea-island type composite fiber (drawn yarn) of 75 denier/ 24 filaments

was prepared. At this time, the number of island components

per filament was 36, the weight ratio of the island component to the sea component was 70 : 30 by weight, and the monofilament fineness of the island component was adjusted to 0.061 denier.

The thusly prepared sea-island type composite fiber was Lised

as the warp and the weft, to thus make a satin fabrics . The fabrics was treated with a sodium hydroxide aqueous solution to dissolve the sea component, dyed and raised, thereby

manufacturing a suede-like fabrics. Various physical properties of the sea-island type composite fiber are as shown in Table 1 . Example 2

A sea-island type composite fiber and a suede-like fabrics were manufactured in the same process and condition as in

Example 1 except that a copolymer polyester having 5mol% of neo-penthylglycol and 8mol% of 1 ,4-cyclohexanedimethanol copolymerized (contained) in polyethylene terephthalate as a main component was used as the island component Lipon conjugated spinning. Various physical properties of the sea-island type composite fiber are as shown in Table 1. Example 3

Example 1 except that a copolymer polyester having 5mol% of 2 ,2-diethyl- l ,3-propanediol and 10mol% of

1 ,5-cycloheptanedimethanol copolymerized (contained) in polyethylene terephthalate as a main component was used as the island component upon conjugated spinning. Various physical properties of the sea-island type composite fiber are as shown in Table 1.

Example 4

A sea-island type composite fiber and a suede-like fabrics were manufactured in the same process and condition as in Example 1 except that a copolymer polyester having 5mol% of 2 ,2-diethyl- l ,3-propanediol and 8mol% of

Example 5

A sea-island type composite fiber and a suede-like fabrics were manufactured in the same process and condition as in Example 1 except that a copolymer polyester having 5mol% of neo-pentylglycol and 10mol% of 1 ,4-cyclohexanedimethanol copolymerized (contained) in polyethylene terephthalate as a main component was used as the island component ' upon conjugated spinning. Various physical properties of the sea-island type composite fiber are as shown in Table 1.

Example 6

A sea-island type composite fiber and a suede-like fabrics were manufactured in the same process and condition as in Example 1 except that a copolymer polyester having 10mol% of neo-pentylglycol and 15mol% of 1 ,4-cyclohexanedimethanol copolymerized (contained) in polyethylene terephthalate as a main component was used as the island component upon conjugated spinning. Various physical properties of the sea-island type composite fiber are as shown in Table 1.

Example 7

A sea-island type composite fiber and a suede-like fabrics were manufactured in the same process and condition as in Example 1 except that a copolymer polyester having 0.5mol% of neo-pentylglycol and 0.5mol% of 1 ,4-cyclohexanedimethanol copolymerized (contained) in polyethylene terephthalate as a main component was used as the island component upon conjugated spinning. Various physical properties of the sea-island type composite fiber are as shown in Table 1. Example 8

By using as a sea component an ionic copolymer polyester dissolvable with a sodium hydroxide aqueous solution and as an island component a copolymer polyester having lmol% of neo-penthylglycol and 2mol% of 1 ,4-cyclohexanedimethanol copolymerized (contained) in polyethylene terephthalate as a main component, a sea-island type composite fiber (drawn yarn) of 75 denier/ 24 filaments was prepared. At this time, the number of island components per filament was 36, the weight ratio of the island component to the sea component was 70:30 by weight, and the monofilament fineness of the island component was adjusted to 0.061 denier. The thusly prepared sea-island type composite fiber was ised to make a loop knit fabrics. The fabrics was treated with a sodium hydroxide aqueous solution to dissolve the sea component, dyed and raised, thereby manufacturing a suede-like fabrics (knit fabrics) . Various physical properties o f the sea-island type composite fiber are as shown in Table 1.

Example 9

A sea-island type composite fiber and a suede-like fabrics were manufactured in the same process and condition as in Example 8 except that a copolymer polyester having 5mol% of neo-pentylglycol and 8mol% of 1 ,4-cyclohexanedimethanol copolymerized (contained) in polyethylene terephthalate as a main component was used as the island component upon conjugated spinning. Various physical properties of the sea-island type composite fiber are as shown in Table 1.

Example 10

Example 8 except that a copolymer polyester having 5mol% o f l ,2-diethyl- l ,3-propanediol and 10mol% of

Example 1 1

A sea-island type composite fiber and a suede-like fabrics were manufactured in the same process and condition as in Example 1 except that a copolymer polyester having 15mol% of 1 ,4-cyclohexanedimethanol copolymerized (contained) in polyethylene terephthalate as a main component was used as the island component upon conjugated spinning. Various physical properties of the sea-island type composite fiber are as shown in Table 1 .

Comparative Example 1

By using as a sea component an ionic copolymer polyester dissolvable with a sodium hydroxide aqueous solution and as an island component a polyethylene terephthalate (unmodified) , a sea-island type composite fiber (drawn yarn) of 75 denier/24 filaments was prepared. At this time, the number of island components per filament was 36, the weight ratio of the island component to the sea component was 70:30 by weight, and the monofilament fineness of the island component was adjusted to 0.061 denier. The thusly prepared sea-island type composite fiber was used as the warp and the weft, to thus make a satin fabrics. The fabrics was treated with a sodium hydroxide aqueous solution to dissolve the sea component, dyed and raised, thereby manufacturing a suede-like fabrics. Various physical properties of the sea-island type composite fiber are as shown in Table 1. Comparative Example 2

By using as a sea component an ionic copolymer polyester dissolvable with a sodium hydroxide aqueous solution and as an island component a polyethylene terephthalate (unmodified) , a sea-island type composite fiber (drawn yarn) of 75 denier/ 24 filaments was prepared. At this time, the number of island components per filament was 36, the weight ratio of the island component to the sea component was 70:30 by weight, and the monofilament fineness of the island component was adjusted to 0.061 denier. The thusly prepared sea-island type composite fiber was used to make a loop knit fabrics. The fabrics was treated with a sodium hydroxide aqueous solution to dissolve the sea component, dyed and raised, thereby manufacturing a suede-like fabrics (knit fabrics) . Various physical properties of the sea-island type composite fiber are as shown in Table 1.

[Table 1]

Result of Evaluation of Physical Properties of Sea-Island Type Composite

Fiber

Claims

WHAT IS CLAIMED IS:

1. A sea-island type composite fiber with excellent color strength, which comprises an island component mainly composed of polyethylene terephthalate and having a monofilament fineness of 0.001 to 0.5 denier and a sea component composed of a copolymer polyester readily soluble to alkali, wherein the island component has a diol comonomer of Chemical Structural Formula (I) and/ or a diol comonomer of Chemical Structural Formula (II) contained therein:

HO CH2 C — - CH2 OH (I)

R2

HO CH2 X CHz OH (I I)

2. The sea-island type composite fiber of claim 1 , wherein, with respect to the island component, the content of the diol comonomer of Chemical Structural Formula (I) is 0.5 to

10mol% and the content of the diol comonomer of Chemical Structural Formula (II) is 0.5 to 15mol%.

3. The sea-island type composite fiber of claim 1 , wherein, with respect to the island component, the content of the diol comonomer of Chemical Structural Formula (I) is 0.5 to 3.0mol% and the content of the diol comonomer of Chemical Structural Formula (II) is 0.5 to 5.0mol%.

4. The sea-island type composite fiber of claim 1 , wherein, with respect to the island component, the content of the diol comonomer of Chemical Structural Formula (I) is 1 to 20mol% .

5. The sea-island type composite fiber of claim 1 , wherein, with respect to the island component, the content of the diol comonomer of Chemical Structural Formula (II) is 1 to 20mol% .

6. The sea-island type composite fiber of claim 1 , wherein the diol comonomer of Chemical Structural Formula (I) is neo-pentylglycol, 2,2-diethyl- l ,3-propanediol or 2,2-ethylmethyl- l ,3-propanediol.

7. The sea-island type composite fiber of claim 1 , wherein the diol comonomer of Chemical Structural Formula (II) is 1 ,4-cyclohexanedimethanol, 1 ,3-cyclopentanedimethanol or 1 ,5-cycloheptanedimethanol.

8. The sea-island type composite fiber of claim 1 , wherein the color strength improvement factor is more than 10%.

9. The sea-island type composite fiber of claim 1 , wherein the weight reduction rate difference is less than 10%.

10. The sea-island type composite fiber of claim 1 , wherein the boil-off shrinkage (of a drawn yarn) is 5 to 15% .

1 1. The sea-island type composite fiber of claim 1 , wherein the melting point of the island component remaining after the dissolution of the sea component is 220 to 240°C .

12. A suede-like fabrics, wherein some or all parts of yarn constituting the suede-like fabrics are ultrafine yarn of a monofilament fineness of 0.001 to 0.5 denier having a diol comonomer of Chemical Structural Formula (I) and/or a diol comonomer of Chemical Structural Formula (II) contained in polyethylene terephthalate as a main component: Ri

I

HO CHa C CHz — OH (1)

R2

[wherein Ri and R2 are an alkyl group with 1 to 3 carbon atoms and X is an aliphatic ring with 5 to 8 carbon atoms.]

13. The suede-like fabrics of claim 12, wherein the suede-like fabrics is a woven fabrics, a warp knitted fabrics or a loop knitted fabrics.

14. A melange-like fabrics made by using some parts of the sea-island type composite fiber with excellent color strength of claim 1.

15. A stripe-like fabrics made by using some parts of the sea-island type composite fiber with excellent color strength of claim 1.