JPS59223314A - Conjugate polyester fiber having different dyeing property - Google Patents

Abstract

PURPOSE:The titled fibers, having cross-shaped cross section, and constituted of polyesters having different dyeing properties in a pair of two legs, and capable of assuming improved grandrelle tone with little difference between spindles. CONSTITUTION:Conjugate polyester fibers having pairs of two ajacent legs (K) and (L) and (M) and (N) constituted of two polyesters 1 and 2 having mutual different dyeing properties in the four legs (K), (L), (M) and (N) extending radially from the center (O) of the cross-shaped cross section thereof. Preferably, each angle (theta) between the mutual adjacent two lengs is 90 deg., and lengths (DK), (DL), (DM) and (DN) from the center (O) of the cross section to the apexes of the respective legs are equal. Widths (WK), (WL), (WM) and (WN) of the respective legs are equal. The polyesters having different dyeing properties are preferably as follows; a combination of one of only ethylene terephthalate units and the other of ethylene terephthalate units containing a copolymerization component dyeable with a cationic dye.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a metachromatic composite polyester fiber exhibiting an excellent heathered tone.

[Prior art]

Conventionally, different dyeing polyester fibers have been produced by mixing two types of filament groups made of polymers with different dyeing properties by twisting two gold threads, interlacing, etc. at an appropriate stage of the weaving process. However, this method of blending fibers has the disadvantage that when produced on a large scale industrially, differences in the weights of the resulting blended yarn are essentially unavoidable. was. As a way to improve this drawback, a heterochromatic composite polyester fiber with a circular cross section in which two types of polymers with different dyeability are arranged side by side in one single fiber has been proposed. In this case, only a uniform neutral color is exhibited, and the heathered appearance effect, which is a characteristic of discolored polyester fibers, is lost, which is a fatal defect.

[Purpose of the invention]

The present invention eliminates the drawbacks of such conventional methods and provides a metachromatic composite polyester fiber that exhibits an extremely excellent heathered tone with a small difference between weights.

[Structure of the invention]

In the present invention, the cross-sectional shape is a cross with four legs extending radially from the center, and two pairs of legs, each consisting of two adjacent legs, have different staining properties. This is a discolorable composite polyester fiber characterized by being composed of polyester that is made of polyester.

The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a cross-sectional view of the fiber according to the present invention. In the same figure, the center O of the cross-shaped fiber cross-section also has four legs extending radially, and two adjacent legs out of L, M, and H. In the pair of feet, L, M, and N have different staining characteristics 2
It is composed of 1 and 2 types of polyester.

In the present invention, the two types of polyesters having different dyeability are 9 For example, one polyester is composed essentially only of ethylene terephthalate units, and the other polyester is 5-sodium-sulfonate which is dyeable with cationic dyes. This refers to a combination of polyesters whose main structural unit is ethylene therephthalate containing a copolymerized component such as isophthalic acid, but is not limited to this combination (including differences in shade, in short, different dyeings). Any combination of polyesters exhibiting properties may be used.

In the cross-shaped fiber cross section of the present invention, as shown in FIG. 2, the angle θ between two adjacent legs is 90.
° (i.e. θKL"θLM-θMN=θHK = 90
°), and as shown in Figure 3, the center O of the fiber cross section and the length from the top of each leg DKr DL, DM,
DN is equal, and each foot width WK, WL, WM
, wN are also preferably equal.

Since the fibers of the present invention are made by imparting metachromatic properties to a single single fiber, the difference between the weights of the so-called heather tone, which is the fundamental cause of the blending of two types of filament groups, is reduced. This does not occur at all in the present invention.

In addition, as shown in Figure 1, the cross section of the fiber is cross-shaped, and out of the four legs, two adjacent legs are paired, giving metachromatic properties to two pairs of legs. .

The different colored parts are moderately different from each other (as in the conventional product shown in Fig. 4, the different colored parts are small and when made into a cloth, it shows only a uniform neutral color.7j l,. .

In other words, because the mixture of the different dyed parts is moderately coarse, the heathered appearance effect is not lost, and a heathered look of extremely high quality can be obtained. The metachromatic composite polyester fiber of the present invention is produced by spinning two types of polyester having different dyeability using a spinning device as shown in Fig. 5 and a spinneret having spinning holes as shown in Fig. 6. It can be easily obtained by subjecting polyester to side-by-side composite melt spinning. It is also possible to impart latent crimpability by rapidly cooling the yarn using cold air at a position where the polymer spun from this spinning spinneret is still in a molten state.

In addition, two types of polyesters with different dyeability usually have different fiber performance (and thermal shrinkage behavior).As a result of arranging the two types of polyesters side-by-side,
Structural latent crimp properties may be imparted in some cases, but such a phenomenon is not a problem in the present invention.

The present invention will be explained in more detail below with reference to Examples.

〔Example〕

Two types of polyesters, polyethylene terephthalate with a relative viscosity (metacresol = 25°C) of 1.65 and S-sodium-sulfoinphthalate with a relative viscosity of 1.50, are prepared by a conventional method. Accordingly, a side-by-side type composite undrawn yarn was spun at a spinning speed of 1000 m/7 min using the spinning apparatus shown in FIG. 5 equipped with the spinneret shown in FIG. 6.

Next, the composite undrawn yarn was stretched 3.5 times using a normal roller plate type drawing and twisting machine, and wound at 500 m/min.
A drawn yarn of 65 denier/15 filaments was obtained. The yarn quality of this drawn yarn is as shown in Table 1. When this drawn yarn was used as the weft yarn to weave into taffeta at a density of 74 yarns/inch and dyed under the dyeing conditions shown in Table 2, a woven fabric exhibiting an aesthetically calm heathered tone was obtained.

Table 1 Table 2 [Comparative Example] A drawn yarn having a Y-shaped cross section shown in FIG. 8 was obtained under the same conditions as in the example except that a spinneret having the spinning hole shown in FIG. 7 was used, and the weaving and When dyed.

It only showed a heathered tone with noticeable streaks, and no aesthetic color effect could be obtained. This is because in the case of a Y-shaped cross section, the side-by-side arrangement of the two types of polyester becomes non-uniform between each filament.

〔Effect of the invention〕

The fiber of the present invention constructed as described above has a small difference between weights and exhibits an extremely excellent heathered texture, and its industrial value is extremely large.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a metachromatic composite polyester fiber according to the present invention, and FIGS. 2 and 3 are cross-sectional views of fibers for explaining preferred embodiments of the present invention. Fig. 4 is a cross-sectional view of a conventional heterochromatic composite polyester fiber, Fig. 5 is a longitudinal cross-sectional view showing an example of a spinning device for obtaining the fiber of the present invention, and Fig. 6 is a cross-sectional view for obtaining the fiber of the present invention. FIG. 7 is a plan view showing an example of the spinning hole of the spinneret used in the comparative example of the present invention, and FIG. 8 is a cross section of the fiber obtained in the comparative example of the present invention. In Figures 1 to 8, (IL) (21 is polyester with different dyeability, (3) is the cap plate, and L, M, and N are the feet. Figure 1+, f) 3 dimensions, 2 squares -”) ve diagram, konfu diagram, 8 diagrams

Claims (1)

[Claims] The cross-sectional shape is a cross with four legs extending radially from the center, and two adjacent legs form a pair.
A metachromatic composite polyester fiber characterized in that the pairs of legs are made of polyester having different dyeability.