KR980009556A - Manufacturing method of latent crimped composite fiber - Google Patents

Abstract

According to the present invention, two kinds of fiber-forming polyesters differing in heat shrinkage are used to emit the excitation components so as to be arranged in a side-by-side structure in the longitudinal direction of the fibers, By using the spinning and spinning processes after the stretching process, it is possible to obtain a polyester-based latent yarn having a soft touch, a soft feeling, a deep color, a drape and a bulky property as well as a remarkably improved spinning workability and yarn- To thereby produce a condensed conjugated fiber.

The hollow 2 slit type composite spinneret has a width D _a and D _b of the slits _a and _b of 0.1 to 0.5 mm and a difference between the widths D _a and D _b of the slits _a and _b 0.2 mm or more and the interval between the slits is 0.2 to 0.4 mm, the polymer having a high viscosity is caused to flow toward the narrow slit width, thereby obtaining a composite fiber excellent in potential winding resistance.

Description

Manufacturing method of latent crimped composite fiber

Figure 1 is a schematic view of the composite spinneret used in the present invention.

FIG. 2 (a) is a sectional view of a yarn showing a cross-sectional shape of the composite fiber of the present invention, and FIG. 2 (b) is a sectional view of a yarn showing a cross-sectional shape of a composite fiber of a comparative example of the present invention.

DESCRIPTION OF THE REFERENCE NUMERALS

1: high shrinkage component 2: low shrinkage component a, b: slit

The present invention is characterized in that two kinds of fiber-forming polyesters differing in heat shrinkability are respectively melted and then spinning is carried out using a composite spinneret having a hollow two slit shape, followed by a stretching process, followed by relaxation heat treatment, To a process for producing a latent crimpable conjugated fiber of polyester which is excellent in deep coloring, drape and bulky properties, and also has remarkably improved spinning workability and workability.

BACKGROUND ART Conventionally, a material improved in properties by mixing two kinds of polymers to improve the winding property, the sophistication, the color tone and the drapability, and the post-processing such as the false twisting process and the alkali reduction process is widely known.

Japanese Unexamined Patent Publication No. 59-59920 and Japanese Patent Publication No. 59-228019 disclose conjugated fibers having improved bulkiness and sophistication by imparting two kinds of polymers having different heat shrinkage behaviors in a fiber form in a bonded form, Japanese Patent Application Laid-Open No. 65-3335 discloses a method for producing a conjugate fiber that improves the winding property by setting conditions to have the maximum winding property by using two kinds of polymers having different heat shrinkage behaviors. However, The composite fibers of the present invention can not have the same properties as natural fibers, such as natural fibers, tactile and crimpability. Moreover, because of the difference in melting point of the double polymer just below the spinneret, the triplet phenomenon can not be fundamentally solved, And it is required to be improved.

Accordingly, an object of the present invention is to provide a polyester-based latent crimping composite which is excellent in smooth touch, gentle, deep color, drape, and bulky properties by solving the projecting phenomenon immediately under the spinneret, It is in obtaining the fiber.

The inventors of the present invention, after a long period of research, have fundamentally solved the above problems by melting the two kinds of fiber-forming polyesters having different heat shrinkable properties, and by spinning composite yarns using composite spinnerets falling within the scope of the present invention, The present inventors have succeeded in manufacturing a latent crimped conjugated fiber having excellent spinning performance as well as improving the uniformity of the yarn by natural bonding under the spinneret,

Hereinafter, the present invention will be described in detail.

In the present invention, two kinds of fiber-forming polyesters having different heat shrinkage ratios are used to spin each component so as to be arranged in a side-by-side structure in the longitudinal direction of the fibers, And then subjecting the resultant mixture to spinning using a spinneret, followed by a stretching process, followed by relaxation heat treatment to give a crimp performance.

The two types of fiber-forming polyesters used in the present invention have mutual affinity, and one of the two polymers requires a large heat shrinkage. The low-shrinkage polymer is obtained by using a conventional polyester polymer (intrinsic viscosity: 0.65 to 0.75, 15 to 25% in terms of heat shrinkage at 180 ° C) and a high shrinkage polymer (Intrinsic viscosity: 0.80 to 0.85, and thermal shrinkage at 180 占 폚: 30 to 50%) is used.

FIG. 1 is a schematic view showing the shape of a composite spinneret used in the present invention, and FIG. 2 is a sectional view of a yarn showing a cross-sectional shape of the yarn spun by the spinneret. Two types of fiber-forming polymers having different heat shrinkages are melted from the extruder, filtered through a metal powder and a filter, and passed through the coating from the outlet to the upper portion of the spinneret through the pot, where the two polymers are bonded, It flows down to escape detention. The polymer exiting the nip is bonded directly to the cooling air stream before being fully solidified to form filaments having an elliptical or circular cross-section.

The shape of the spinneret used in the present invention is preferably a hollow-type two-slit shape, and a shape of three to four slits is inappropriate for use because a hollow-sectioned yarn is produced. When the hollow is formed, the reason for cooling the polymer directly under the detention causes degradation of the uniformity of the yarn. This phenomenon becomes more serious and the uniformity of the yarn is deteriorated, which is inappropriate.

The shape of the spinneret used in the present invention is preferably a hollow-type two-slit shape, and a shape of three to four slits is inappropriate for use because a hollow-sectioned yarn is produced. When the hollow is formed, there is a decrease in the homogeneity of the yarn, such as the reason for the cooling of the polymer just under the custody, and this phenomenon becomes more serious and the uniformity of the yarn is deteriorated and is inadequate.

The widths Da and Db of the slits (a) and (b) are suitably between 0.1 and 0.5 mm. When the slits a and b are smaller than 0.1 mm, it is impossible to clean the polymer residue or the like during spin cleaning. When it is low, the reason for radiation is severe, so the rate of rejection increases due to the contact of the people.

In addition, the difference between the widths D _a and D _b of the slits (a) and (b) should be 0.2 mm or more, and the polymer having a low melt viscosity should be flowed with a small width of the slit. If it is less than 0.2 mm, it is difficult to detach wiping due to the prying phenomenon directly under the detention.

The gap between the slits should be 0.2 to 0.4 mm. When the thickness is less than 0.2 mm, the polymer melt is bonded in a state where the polymer melt is not sufficiently cooled, and pruning is likely to occur. If it is within this range, a 1: 1 side-by-side yarn cross-section is obtained in which no hollow is formed due to swelling of the polymer directly under the crotch.

The produced filament is subjected to a stretching process at a temperature of 100 to 120 ° C and 180 to 200 ° C, respectively, with the first rollers in a stretching machine and subjected to relaxation heat treatment with dry heat or wet heat to give crimpability, As a principle of bimetal which is a simple flat yarn but has a different thermal expansion coefficient, a fiber having a soft touch, a deep color feeling, a drape property and a bulky property can be obtained by forming a clamp by a difference in heat shrinkage between two polymers.

Hereinafter, the present invention will be described in detail by way of examples and comparative examples.

The evaluation methods of the crimp extensibility (A), the crimp recovery rate (B), and the crimpability (C) of the fibers used in Examples and Comparative Examples of the present invention are as follows.

1. Crimp elongation (A)

At a tension of 0.05 g / d, reel up to 10,000 d (one side at 5,000 d) to form a skein. Immediately after making the tarsal, put on a 10 g of ultra-heavy load and leave for 5 minutes. Measure the length (L) of the tarsal. Next, 10 g of the initial load is applied to the tread, and the water is soaked in the hot water at 90 ° C. while the water is wet. Then, measure the length (L1) of the tare under 10 g of the initial load, and measure the length (L2) of the tare after 30 seconds after placing the main load of 990 g on the initial load. After the L2 measurement, the main load (990 g) is removed and after 30 seconds elapsed, the length L3 of the tuft is measured in the initial load.

The crimp extension rate and the crimp recovery rate are calculated using the length of the tufts measured above and the following formula.

Crimp elongation percentage (A) = (L2-L1) / L2 占 100 Cylinder recovery rate (B) = (L2-L3) / L2 占 100

2. Number of crimp (C)

Take samples as short fibers and make 10 copies of each 5 cm at a load of 0.05 g / d as long as possible without tensile force.

[Example 1]

Polybutylene terephthalate having an intrinsic viscosity of 0.65 and polyethyleneterephthalate high-viscosity copolymer having an intrinsic viscosity of 0.73 containing 13.5% of dimethylene isophthalate were co-spun at 288 占 폚 in a combined ratio of 1: 1 to 1,300 mpm Wound

At this time, a slit a having a width of 0.12 mm, a slit b having a width of 0.35 mm and a slit spacing of 0.25 mm was used, and a polymer having a high intrinsic viscosity was caused to flow toward the slit a. Thereafter, the stretching process is performed under the conditions of a draw ratio of 2.95 times and a stretching temperature of 110/190 占 폚, and relaxation heat treatment after stretching is performed at a humid temperature of 80 占 폚 for 5 minutes. The characteristics of the yarn thus obtained are shown in the table.

[Example 2]

A polybutylene terephthalate having an intrinsic viscosity of 0.85 and a polyethylene terephthalate having an intrinsic viscosity of 0.66 and having a difference in intrinsic viscosity of 0.25 and a difference in melting point of 1,500 poises at a spinning temperature, And then wound at 1,500 mpm.

At this time, a slit a having a width of 0.18 mm, a slit b having a width of 0.39 mm and a slit spacing of 0.35 mm was used, and a polymer having a high intrinsic viscosity was caused to flow toward the slit a. Thereafter, the stretching process is performed under the conditions of a draw ratio of 3.12 times and a stretching temperature of 120/180 占 폚. After the stretching, the relaxation heat treatment is performed for 5 minutes at a humid temperature of 80 占 폚. The characteristics of the yarn thus obtained are shown in the table.

[Comparative Example 1]

Polybutylene terephthalate having an intrinsic viscosity of 0.65 and polyethylene terephthalate high shear copolymer containing 13% of dimethylene isophthalate having an intrinsic viscosity of 0.73 were combined and spin-cast at 288 ° C in a composite ratio of 1: 1 to obtain 1,400 mpm Lt; / RTI >

In this case, a hole having a diameter of 0.23 mm, a hole having a thickness of 18 mm, a hole having a depth of 0.1 mm, a slit b having a width of 0.28 mm and a slit spacing of 0.25 mm was used. The high polymer was allowed to flow toward the slit b. Thereafter, the stretching process is performed under the conditions of a draw ratio of 2.95 times and a stretching temperature of 110/190 占 폚, and relaxation heat treatment after stretching is performed at a humid temperature of 80 占 폚 for 5 minutes. The characteristics of the yarn thus obtained are shown in the table.

[Comparative Example 2]

In Comparative Example 1, a slit a having a width of 0.12 mm, a slit b of 0.28 mm and a slit spacing of 0.45 mm was used as a hole having a hole inner diameter of 0.23 mm, a slit thickness of 18 mm and a detent inlet of 3 mm. Except that a high polymer was allowed to flow toward the slit a. The characteristics of the yarn thus obtained are shown in the table.

[Comparative Example 3]

In Comparative Example 1, a slit a having a width of 0.12 mm, a slit b having a width of 0.28 mm, and a slit interval of 0.45 mm was used for a hole having a hole diameter of 0.24 mm, a slit thickness of 18 mm, Except that a polymer having a high viscosity was caused to flow toward the slit b. The properties of the yarn thus obtained are shown in the table

table. Crimp Properties of Polyester Composite Fiber

Claims (2)

Using two kinds of fiber-forming polyesters having different heat shrinkage, in the spinning so that the awakening matter is arranged in a side-by-side structure in the longitudinal direction of the fibers, And then subjecting the resultant mixture to spinning and stretching, followed by relaxation heat treatment to give crimpability. The composite spinning and dipping machine according to claim 1, wherein the widths D _{a and} D _bb of the slit (a) and the slit (b) are 0.1 to 0.5 mm, the widths D _{a and} b b of the slit (a) D _b is set to 0.2 mm or more and the interval between slits is set to 0.2 to 0.4 mm, so that the polymer having a high viscosity is caused to flow toward a narrow slit width. ※ Note: It is disclosed by the contents of the first application.