JPH0411005A - Special cross-section fiber and spinning nozzle therefor - Google Patents

Abstract

PURPOSE:To provide the title fiber to be used in e.g. clothing, improved in loosening nature and the whitening gloss due to surface reflection, having unevennesses along the outer periphery of its cross section and having each specified value of flatness ratio and the diameter ratio for the circles inscribed at the recesses present at various parts of the cross section. CONSTITUTION:A polyester melt such as of polyethylene terephthalate is spun by delivery through a nozzle. This nozzle is such that a circular hole B with a diameter of RB and a circular hole C with a diameter of RC are successively connected to both sides of a circular hole A with a diameter of RA through a slit with a width L1, and when the distance between the centers of said holes B and C is defined as L2 and that for the holes A and C as L3, these satisfy the relationships I-III. The objective fiber thus obtained has the following characteristics; (1) having at least 4 recesses and at least 6 projections along the outer periphery of the cross section; (2) flatness ratio being 2.5 to 6; and (3) (a) a circle a with a diameter of ra inscribed in the two projections at the center of the cross section, (b) a circle b with a diameter of rb inscribed in the two other projections adjacent to the above projections and (c) a circle c with a diameter of rc inscribed in the projections at the end of the major axis of the cross section, satisfying the relationships.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a special cross-section synthetic fiber suitable for clothing, moquettes, high bails, carpets, etc., and a spinning nozzle used for its production. The present invention relates to a synthetic fiber with a special cross section that has improved handling properties (writing) due to the synergistic effect of the flatness of the fiber cross section and the unevenness effect, and white blurring properties due to surface reflection, and a method for producing the same.

<Prior Art> Conventionally, synthetic fibers such as polyester, nylon, and acrylic have been used in various fields of application, such as clothing, moquettes, high piles, and carpets, with different cross-sectional shapes. For example, for clothing, fibers with a round cross section,
In addition to round cross-section fibers, flat irregular cross-section fibers are used in moquettes, high bails, etc., and round cross-section and irregular cross-section fibers are used in carpets.

However, in recent years, regardless of the field of application, the artificial luster and texture of round cross-section fibers have become obsolete, and irregular cross-section fibers have become widely used, and they can be obtained by using a special shaped die. .

In particular, irregular cross-section fibers for piles were published in Japanese Patent Application Laid-Open No. 50-5952.
4, JP-A-63-315606, JP-A-Sho 6
It has been proposed in Publication No. 3-59454 and the like.

<Problems to be Solved by the Invention> Even if fibers with irregular cross-sections have about four convex portions in their cross section, even if they are used as pile yarn for moquettes, the surface of the moquettes will appear whitish depending on the way the light rays hit the moquettes and the viewing angle. appear. The so-called "white blur" is noticeable, and when you rub your finger on the surface of the moquette, you can see the marks left behind. So-called "finger marks" are conspicuous and have not been eliminated to a level that satisfies the product appearance.

On the other hand, in order to eliminate white fading and finger marks, it has been considered to use fibers with a large fineness as pile yarn, but this has the disadvantage that the texture of the moquette becomes rough and hard.

On the other hand, a round cross section has poor hair handling properties, which tends to cause threads to get tangled and cause white blurring and finger marks when used as a moquette fabric.

Furthermore, the fabrics using pile yarns made of irregular cross-section fibers as seen in the above-mentioned publications have a stiff feel or have noticeable hair fall, and pile fabrics with a soft feel and less hair fall are advantageous. The current situation is that this is not the case.

The object of the present invention is to solve the above-mentioned drawbacks, and to provide a means for solving the problems in a mellow manner, with fewer white blurs and finger marks when made into a moquette, etc., with less falling of pile hair. At least 4 along the outer circumference of the fiber cross-section
It has at least 6 concave portions and at least 6 convex portions, and has an aspect ratio of 2.
5 to 6 flat cross-section fibers, a circle a with a diameter ra inscribed in two convex portions existing at the center of the cross section, and a circle with a diameter r5 inscribed in the other two convex portions adjacent to the convex portions. and a circle C with a diameter rc inscribed in the convex part at the end in the long axis direction of the cross section, and the following conditions (a) and (α) are satisfied, and ra>rゎ>rc
(b)ra
:rb: rc=3.5~1.7+ 2.5~1.2:
l ([+) A nozzle in which a circular hole B with a diameter R6 and a circular hole C with a diameter RC are successively connected on both sides of a circular hole A with a diameter RA by a slit with a width L1, and RASRB and R
When C satisfies the following (c) and (d), and the distance between the centers of circular hole B and circular hole C is 2, and the distance between the centers of circular hole A and circular hole C is L3, then L1, Ll, This spinning nozzle is characterized in that the following condition (f) is satisfied between L3 and L3.

RA>R11≧ RC (8) RA: RB: RC= 1.2~3: 1~
2.5: 1 (d)L, :Ll:Ll
l: 3-6 6-10 (f) The fiber of the present invention must have at least 4 concave portions and at least 6 convex portions along the outer periphery of the fiber cross section, as shown in FIG. If the number of irregularities is small, it is not possible to make the gloss mellow, and problems such as white blur and finger marks when used as a moquette cannot be solved. On the other hand, if there are too many irregularities, it becomes difficult to manufacture the fiber, the convex parts become less noticeable, and the effect of improving white blur tends to be weakened.

Therefore, the number of concave portions is preferably 4 to 8, and the number of convex portions is preferably 6 to 10. In addition, the fiber cross section of the present invention has an aspect ratio of 2.5 to 6, and as shown in FIG. The following conditions must be satisfied between a circle with a diameter r゜ inscribed in the other two adjacent convex parts and a circle C inscribed in the convex part at the end in the longitudinal direction of the cross section.

ra>rb>rc
(b) ra: rb: rc=
3.5~1.7: 2.5~[2: I ([+) The aspect ratio is the length of the major axis of the fiber cross section as shown in Figure 1 (1)! Or, as shown in Figure 1 (2), it indicates the ratio l/ra between E and the diameter r1 of the inscribed circle a at the center of the fiber cross section, and if this value is less than 2.5, it is a pile fabric. is on the verge of becoming hard.

On the other hand, if it exceeds 6, it is not preferable because it becomes too flat and the fibers tend to fall, or the fibers may split at the recesses in the subsequent process. Further, even if the condition of ra>rb>rc is not satisfied, the hairs tend to fall down easily or become easily divided in the recessed portions.

Therefore, in the present invention, ra exists in the center of the fiber cross section as the largest inscribed circle, and rt+
It is important to reduce Src. "6: r.b.
: If the ratio of rc is out of the above range, the texture may become hard, which is not preferable.

In the fiber of the present invention, the inscribed circles a and bSc are as shown in Fig. 1 (
Their centers may be on a straight line, as shown in 1), or the centers of each round may be arranged on an arc, as shown in FIG. 1(2).

However, when it exists on a circular arc, it is desirable that the ratio d/A of d jump shown in FIG. 1 (2) is 1/2 or less. If an attempt is made to obtain a value exceeding 1/2, the convex portions will become inconspicuous, and the effects of the present invention may not be fully exhibited.

In addition, it is not preferable that each recess is formed too deeply toward the inside of the fiber cross section;
Not only is it difficult to manufacture the fiber itself, but such fibers are easily damaged and split during spinning, processing, etc. processes, so the final product obtained is also unsatisfactory.

The polymer constituting the fiber of the present invention may be any thermoplastic polymer having fiber-forming ability, such as polyester, polyamide, polyolefin, etc., among others, polyethylene terephthalate (PET), Polyesters such as polybutylene terephthalate (PBT) are preferred. In particular, these polyesters include carboxylic acid components such as isophthalic acid, 5-sodium sulfoisophthalic acid, and adipic acid as third components, alcohol components such as diethylene glycol, methoxypolyethylene glycol, and pentaerythritol, and others, which are generally used as copolymerization components. It may be modified with a compound.

In addition, inorganic particles, fragrances, antibacterial agents, flame retardants, deodorants,
It may also contain modifiers such as pigments, matting agents, heat stabilizers, or antistatic agents.

The thickness of the synthetic fiber having a flat cross-sectional shape varies depending on the use, but is, for example, 0.1 to 60 deniers.

When the fiber of the present invention contains a matting agent, effects unimaginable with conventional fibers can be expected.

For example, titanium dioxide, which has been used conventionally, has a 0.
When polyester fibers containing 0.05 to 0.8% by weight (round cross section) are applied to clothing, if the color is made lighter, the underlying layer will appear to be visible.However, in the case of the fiber of the present invention, unevenness The light scattering effect created by the random surface not only eliminates the phenomenon of scattering, but also
This gives it a gentle shine. In addition, the amount of titanium dioxide is increased to 1% by weight or more to create the so-called Furdal brand, and when used for high pile, moquette, etc., it not only has an opaque effect on the fibers, but also matches the cross-sectional shape and has a very animal hair-like appearance. It is possible to obtain fibers having a unique appearance and texture.

The manufacturing method of the fiber of the present invention is not particularly limited as long as its shape satisfies the above requirements. The method for manufacturing the fiber shown in FIG. 1 will be described in detail below as an example of the method for manufacturing the fiber of the present invention.

The spinning nozzle of the present invention has, for example, a cross-sectional shape as shown in FIG.
0.8 cm" or more, particularly preferably 0.12 mm" or more. If this cross-sectional area is smaller than 0.05 mm, the influence of the balancing effect during spinning becomes large, making it difficult to obtain the desired fiber cross-sectional shape.

In the spinning nozzle of the present invention, as shown in Fig. 2, a circular hole A with a diameter RA is successively connected with a circular hole B with a diameter RC and a circular hole C with a diameter RC with a slit of a width L1 on both sides of the circular hole A with a diameter RA.
and RC, RA>RB on EC(c) RA: RC: RC= 1.2~3: 1
~2.5:1 Satisfying (d), circular hole B
and the distance between the centers of the circular hole C.

Then, between L, SLl, and L, Lp Lm:
L, = l: 3-6: 6-10
(book) must be satisfied.

If RA, R@, and RC do not satisfy the conditions (8) and (d) above, and Ll, Lm, and R do not satisfy the condition (n) above, the specified special cross-section fiber of the present invention is obtained. It is not possible.

In the spinning nozzle of the present invention, in order to obtain the desired fiber cross section, even if the centers of the circular holes A, B, and C are substantially aligned in a straight line (Fig. 2 (1)), They may be arranged on an arc (FIG. 2 (2)). In particular, in the case of spinning nozzles arranged in a circular arc, it is desirable that the ratio D/L between D and L shown in FIG. 2 (2) is 1/2 or less.

The special cross-section fiber of the present invention can be produced by spinning a thermoplastic polymer melt by a known method using the above-mentioned spinning nozzle, and subjecting it to appropriate stretching, crimping, heat treatment, etc., but preferably. , 0.3 to 2 in the zone of 3 to 50C directly below the cap
．． Cool by blowing cooling air at 0+/second to create a draft of 50
It is desirable to pick up the item at this time.

The cooling air is preferably blown in a direction parallel to the longitudinal direction of the cross-sectional shape of the spinning nozzle.

When cooling under conditions that are milder than the above condition range, it is difficult to obtain the desired fiber cross-sectional shape, and when cooling under conditions that are harsher than those of the present invention, the spinning condition deteriorates, causing problems in operability. There are cases.

If the spinning draft is less than 50, the spinnability may deteriorate or the fiber cross section may become dango-like, so it is preferably 1.
Must be 50 or more. Further, the spinning take-off speed is suitably 600 to 1.50 rom/min, which is a commonly used speed, but there is no problem in spinning at a speed higher than this.

<Effects of the Invention> According to the present invention, it is possible to obtain a special cross-section fiber that suppresses white blurring and finger marks when made into moquettes, etc., and provides a mellow luster and flexible texture with less falling of the pile, and can be used for various purposes. Suitable as raw cotton for woven or knitted fabrics.

<Examples> Hereinafter, the present invention will be specifically explained using Examples, but the present invention is not limited to these in any way. Incidentally, the measured values in the examples were determined by the following method.

O intrinsic viscosity [η Measured at 30°C after dissolving in a mixed solvent of equal weights of coniphenol and tetrachloroethane.

O Glossiness: A cotton-like sample was thoroughly opened, aligned and fixed on a white board, and the incident light angles were set to 22.5°, 45°, and 50° using a photoelectric spectrophotometer T-50 manufactured by Shimadzu Corporation. The reflectance at each light receiving angle of 22.5°, 45°, and 50° was measured. Furthermore, the total value of these reflectances was also determined.

Example 1 A polyethylene terephthalate melt having an intrinsic viscosity [η] of 0.63 dl/g was treated as shown in FIG. 2 (1) = 0.
25s+s, RB=0.20am, RC=0
．． 16ats (RA: RB: RC=1
．． 6: 1.3: 1), L, = 0.07mm
, Lt=0.325as, Ls=0.605n+m(
LI: Lm: Ls=l: 285°C, 0
．． It was extruded and rolled up at 7 g/m1nH. The spinning conditions were as follows: 24°C cooling air was blown at 0.6 m/sec from around the spun yarn at a distance of 4 cto to 24 cm directly below the spinneret.
It was taken at a draft of 250 and a take-up speed of 900 a/min. A tow of the spun fibers was drawn in a water bath according to a conventional method and cut into stable fibers having a fineness of 2 denier. The cross section of this fiber has a shape as shown in Figure 1 (1), and ra : rb : rc = 2.25
: 2, s : 1, and the aspect ratio was 3.2.

In addition, the gloss of this fiber is 22.5@93.5%, 4
5° Te 51.0%, 50° Te 35.5%, total 180%
This made it possible to obtain fibers with mild gloss and excellent texture, which had never been seen before.

Example 2 A polyethylene terephthalate melt having an intrinsic viscosity [η] of 0.64 dl/g and a titanium dioxide content of 2% by weight had a cross-sectional shape as shown in FIG. 2 (2) and R = 0.25■
, R+s=0.20mm, RC=O,1
6m5 (RA: RB: RC=
1.6: 1.3: 1), L+=0.071
11m, Lt=Ro, 325mm, L, s=0.605m
g+(Lt: Lt: La=1: 4.6: 8.
6), L=0.50+u+.

D = 0.2hm, (D/L = 0.4) nozzle 6
It was extruded at 285°C from a 48-piece die.

Cooling air at 25°C was blown around the spun yarn at 0.75 m/sec from 4 ca to 24 cm directly below the spinneret, with a draft of 425 and a take-up speed of 120 (In
I picked it up in / minutes. The fibers were then bundled into tows, drawn in a water bath according to a conventional method, mechanically crimped, heat treated, and cut into stable fibers having a fineness of 2.5 denier.

The obtained stable fiber has a shape as shown in Fig. 1 (2), and ra : rb : rc = 2.2
: 1.6:1, and the aspect ratio was 3.8. In addition, the gloss of this fiber is 73.8% at 22.5°, 45
．． 40.2% at 0°, 28.0% at 50.0° Total 1
42%, and fibers with excellent texture could be obtained.

[Brief explanation of drawings]

FIG. 1 is a diagram illustrating the cross-sectional shape of the special cross-section fiber of the present invention, where (1) shows that the centers of inscribed circles a, b, and C are aligned in a straight line, and (2) indicates that the centers are arranged on a circular arc. FIG. 2 is a diagram illustrating the cross-sectional shape of the spinning nozzle of the present invention, (1) shows the spinning nozzle for producing the fiber of FIG. ) shows a spinning nozzle for producing fibers. Patent applicant RiRa Shi Co., Ltd.

Claims (1)

[Scope of Claims] (1) A flat cross-section fiber having at least 4 concave portions and at least 6 convex portions along the outer periphery of the fiber cross section, and having an oblateness ratio of 2.5 to 6, and existing at the center of the cross section. A circle_a with a diameter r_a inscribed in the two convex parts, a circle b with a diameter r_b inscribed in the other two convex parts adjacent to the convex part, and a diameter inscribed in the convex part at the end in the long axis direction of the cross section. A special cross-sectional fiber characterized in that the following conditions (a) and (b) are satisfied between r_c and circle c. r_a>r_b>r_c (a) r_a:r_b:r_c=3.5~1.7:2.5~1
．． 2:1 (b) (2) The special cross-section fiber according to claim (1), characterized in that the centers of each of the inscribed circles a, b, and c lie substantially on a straight line or on a circular arc. (3) A nozzle in which a circular hole A with a diameter R_A is successively connected on both sides with a circular hole B with a diameter R_B and a circular hole C with a diameter R_C by a slit with a width L_1, where R_A, R_B and R_C are ), (d), and when the distance between the centers of circular hole B and circular hole C is L_2, and the distance between the centers of circular hole A and circular hole C is L_3, L_1, L_2 and L
A spinning nozzle characterized in that the following condition (e) is satisfied between __3. R_A>R_B≧R_C (c) R_A:R_B:R_C=1.2~3:1~2.5:1
(d) L_1:L_2:L_3=1:3~6:6~10
(e) (4) The spinning nozzle according to claim (3), wherein the centers of the circular holes A, B, and C are located on a straight line or on a circular arc.