JPS6221818A - Production of combined filament polyester yarn having different fineness - Google Patents

Abstract

PURPOSE:To obtain the titled combined filament yarn free from fluffing and loop and dyeable to deep color, by adding (meta)kaolin to a polyester polymer, and extruding two kinds of molten filament groups having different single filament fineness through a single spinneret for melt-spinning. CONSTITUTION:A polyester polymer compounded with 0.1-5.0wt%, preferably 0.5-2.0wt% kaolin or metakaolin is melted and extruded through a single spinneret in the form of two kinds of filament groups wherein the single filament fineness of a filament group is $,1.5 times that of the other filament group. The extruded filament groups are doubled and wound to obtain an undrawn fiber bundle, which is drawn at the same time under the same drawing condition and heat-treated. The widths of the optimum draw ratio regions X, Y are expanded and the doubled yarn can be drawn at a draw ratio corresponding to the overlapped region Z.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a method for producing mixed fiber yarn of different fineness, and more specifically, by blending kaolin or metakaolin with a polyester polymer, yarn unevenness is good and deep dyeing is achieved. The present invention relates to a method for producing a polyester mixed fiber yarn having different densities.

[Conventional technology]

As a method of imparting a contradictory texture to polyester fabrics, such as softness and firmness or firmness, a so-called mixed yarn of different fineness is known, which is a mixture of two types of filament groups having different single fiber finenesses.

As a manufacturing method for this polyester mixed fiber yarn of different fineness, two types of filament groups with different single fiber finenesses are simultaneously melted and discharged from the same melt spinneret, aligned and wound. A method has been adopted in which the film is supplied to a normal stretching device, stretched at the same stretching temperature and the same stretching ratio, subjected to heat treatment, and then wound up on a burner.

However, two types of filament groups with different single fiber finenesses and therefore different orientations of the internal fiber structure naturally have different ranges of appropriate draw ratios, so they cannot be drawn at the same drawing temperature and the same draw ratio. When stretched, fuzz, loops, or thick and thin spots occur in the longitudinal direction of the fibers. In other words, a group of filaments with a small single fiber fineness has a thicker orientation of the internal structure of the fibers than a group of filaments with a large single fiber fineness (therefore, the range of appropriate draw ratio is lower, so the drawing temperature and draw ratio should be adjusted accordingly). When the conditions are set to be favorable for a filament group with a small single fiber fineness, drawing unevenness (referred to as necking) that forms thick and thin lines along the longitudinal direction of the fibers will occur in a filament group with a large single fiber fineness, and on the other hand, the stretching temperature and the stretching ratio If the conditions are set to be favorable for the filament group with large single fiber fineness, yarn breakage or single fiber breakage will occur in the filament group with small single fiber fineness, and in the end, it has not been possible to find appropriate conditions that satisfy both filament groups. It was not possible to make the ratio of the single fiber fineness of the two types of filament groups 1.5 or more.

FIG. 2 shows the stress-elongation curves of two types of conventional undrawn filaments having different single fiber finenesses and the range of appropriate draw ratios. Filament group with small single fiber fineness (curve A
), the X region is the region with the appropriate draw ratio, and in the filament group with large single fiber fineness (curve B), the Y region is the region with the appropriate draw ratio, and there is no overlapping portion that satisfies both.

Here, the appropriate stretching ratio refers to a stretching ratio in which there are no unevenness in the longitudinal direction of the fibers and the elongation at break falls within a practically preferable range of 20 to 60%.

[Problem that the invention seeks to solve]

The present invention solves such problems in the conventional method, and is capable of producing two fibers with different finenesses from the same melt spinneret.
By melting and discharging food filaments at the same time, pulling them together and winding them, the polyester polymer of the undrawn polyester mixed fiber yarn of different densities is added with inorganic fine particles of kaolin or metakaolin. Among them, the range of appropriate stretching ratios for filaments with a particularly large single fiber fineness and, therefore, a small orientation of the internal structure of the fibers has been expanded. The purpose of this invention is to produce a polyester mixed fiber yarn with dyeability.

[Means for solving problems]

The gist of the present invention is to provide a method for producing a polyester mixed yarn of different finenesses, which is composed of two types of filament groups having different single fiber finenesses, in which kaolin or metakaolin is added in a range of 0.1 to 5. A polyester polymer containing 0 wt% is melted and discharged from the same melt spinneret so as to simultaneously form two types of filament groups that differ in single fiber fineness by at least 1.5 times, and the undrawn fiber bundle that is drawn and wound is drawn. This is a method for producing a polyester mixed fiber yarn of different fineness having good unevenness and deep dyeing properties, which is characterized by supplying the yarn to an apparatus, simultaneously stretching it under the same stretching temperature and stretching ratio, and subjecting it to heat treatment.

The present invention will be explained in more detail below.

Surprisingly, when drawing undrawn polyester fibers containing kaolin or metakaolin, the drawing ratio is relatively low, e.g. 78-100
Thick and fine spots (
In particular, when the degree of polymerization of the polyester polymer is low, the presence or absence of kaolin or metakaolin can be stretched without causing necking.
There is a marked difference in the occurrence of

Furthermore, kaolin or metakaolin has a refractive index close to that of polyethylene terephthalate, and unlike the case where a matting agent such as titanium oxide is blended, a gentle glossiness can be obtained.

The ability to perform low-stretching ratio stretching, which is a special stretching condition of the present invention, brings about the following effects. (1) Curves A and B in Figure 2
The width of X and Y, which is the area of the appropriate stretching ratio shown in Fig. 1, widens, and a portion 2 where X and Y overlap occurs as shown in curves A and B in Fig. 1, and the stretching corresponding to this overlapped portion 2 occurs. By selecting the magnification and drawing, both the filament group with small single fiber fineness (curve A) and the filament group with large single fiber fineness (curve B) will have no fluff or loops, or will be thick and fine in the longitudinal direction of the fiber (curve B). It is now possible to produce a polyester mixed fiber yarn of different fineness without necking, and the ratio of single fiber fineness can be increased to 1.5 or more, which was extremely difficult in the past.

(2) The optical effect of kaolin or metakaolin on light reflection, that is, the effect of reducing specularly reflected light on the fiber surface and increasing the transmitted light inside the fiber, and the loose crystal structure inside the fiber resulting from the low-magnification stretching. Due to this effect, deep dyeing properties are imparted to polyester mixed fiber yarns of different fineness.

Due to the blending of kaolin or metakaolin, thinning in the longitudinal direction of the fibers (necking) that tends to occur when drawing at low magnification.
The reason why this is suppressed is not fully clear, but the rearrangement of the polymer chains is carried out smoothly due to the sliding friction mechanism of the internal particles of the polymer or the mechanism of the internal particles of the polymer as a nucleating agent. The stretching deformation on the metal surface of the stretching roller or stretching bottle may be caused by the reduction of the friction against the metal due to these fine particles protruding on the fiber surface.
This is thought to be because it is done smoothly.

The kaolin used in the present invention may be any of kaolinite, hallosite, dietskiite, nacrite, etc., but it is particularly desirable to have a particle size of 5 μm or less and less impurities. Among these, kaolinite is particularly good. Furthermore, metakaolin which has become amorphous in terms of X-ray diffraction obtained by firing kaolinite at a temperature of 500 to 1000°C may of course be used.

Kaolin or metakaolin obtained by calcining kaolin is classified by appropriate means such as flotation or simple water brush classification so that it does not substantially contain coarse particles of 5 microns or more. When coarse particles of 5 μm or more are blended into a polyester polymer and spun, the filter in the nozzle becomes clogged, the overpressure rises significantly, and spinning becomes practically difficult. In addition, the strength of the thread may be reduced.

Iron and other impurities that could not be removed in the case of kaolin can be easily removed by operations such as flotation or water brush classification when calcined to produce metakaolin, so metakaolin is preferred from the viewpoint of coloring of the polymer due to impurities.

The amount of kaolin to be blended is generally 0.1 to 5 wt%, preferably 0.5 to 2.0 wt%, based on the polyester polymer.
It is 0wt%. Q, If the amount is less than 1 wt%, the effect of expanding the range of appropriate stretching ratio and deep dyeing property will be small, and 5
If the amount exceeds wt%, it is not preferable because the spinning properties and quality of the yarn deteriorate. In addition, there are two methods of compounding: adding to the reaction system before or during polymerization of the polyester polymer, and adding after polymerization. It is preferable to do so. In this case, it is of course possible to use a dispersant in combination, if necessary, to prevent particle agglomeration. Kaolin or metakaolin used in the present invention has a refractive index close to that of polyester polymer, so it exhibits a calm luster,
Furthermore, since the light that passes through the fibers is captured at the interface between the polyester polymer and the kaolin fine particles and within the kaolin fine particles, it exhibits a deep, rich color after dyeing.

In the present invention, metakaolin is amorphous in terms of X-ray diffraction means a state in which the X-ray diffraction characteristic of the crystal lattice of kaolin is no longer observed when ordinary powder X-ray diffraction is performed. The polyester polymer of the present invention refers to a polyester polymer in which substantially 85 mol% or more is composed of repeating units of ethylene terephthalate, and the polyester polymer is used for the purpose of imparting color clarity or atmospheric pressure dyeability. Of course, it is also possible to copolymerize a dicarboxylic acid component such as 5-sodium sulfoisophthalic acid or (and) adipic acid as a third component within a range not exceeding 15 mol %.

Further, in the present invention, it is of course possible to mix only one of kaolin and metakaolin, but it is also possible to mix the two in any ratio.

Specifically, the polyester polymer blended with kaolin or metakaolin used in the present invention is produced, for example, as follows. That is, by the direct polymerization method, terephthalic acid and ethylene glycol were charged into a polymerization pot so that the molar ratio was 1=2, and at the same time, antimony dioxide was added as a catalyst in a molar ratio of 0.005% to terephthalic acid. The mixture is reacted under a pressure of 40 atm while controlling the final temperature at 240° C. while discharging the produced water from the system.

When water no longer occurs, transfer to an autoclave.
An ethylene glycol slurry in which 20 wt% metakaolin is dispersed is gradually added while stirring, and the amount of metakaolin is adjusted to 1.5% by weight based on the final polyethylene terephthalate. While stirring, gradually reduce the internal pressure of the autoclave to 0.1 tax H,P.
Ethylene glycol vapor is continuously removed from the system to a final temperature of 280°C. This mixture is polymerized until the intrinsic viscosity reaches 0.64, extruded into water, cooled, and then cut to obtain chips. The polymer chips thus obtained are vacuum dried, fed to a screw extruder, and melt-spun.

The undrawn fibers of the polyester polymer used in the present invention have a birefringence Δn of 10XIO to 45×10, preferably 1
It is necessary that the birefringence is in the range of 5X10 to 35X10-''.If the birefringence Δn is less than 10XIO, stretching unevenness tends to occur during stretching, and if it exceeds 45X10, cooling unevenness will occur during spinning, so it is preferable. do not have.

In carrying out the present invention, such specific undrawn fibers are drawn using a conventional drawing/twisting machine or drawing machine. The stretching temperature is the glass transition temperature of polyester (T,)"C~T
I+40°C, preferably in the range of T/+5°C to T/+30°C; below TP°C, stretching unevenness, particularly necking, is unavoidable and the uniformity of dyeing is reduced. Further, at a temperature exceeding T7+40'c, the stretching tension decreases, the stretching point changes, and streak-like staining spots occur, which is not preferable. Further, the heating body in the stretching zone may be of a contact type or a slit-shaped non-contact type. The temperature of this heating body is in the range of 120 to 200°C, preferably 130 to 180°C. If the temperature of the heating element is lower than 120°C, the fine internal structure of the drawn fibers obtained will not be sufficiently heat-set, resulting in a high submerged shrinkage rate, a hard texture, and wrinkles when made into a highly twisted fabric. becomes worse. Moreover, when the temperature exceeds 200°C, the drawing stability is extremely reduced, and fuzz and loops occur frequently in the filament group having a large single fiber fineness and therefore a low orientation.

The selection of the draw ratio is important in the present invention, and the maximum draw ratio that allows two types of filament groups with different single fiber finenesses to be drawn without breaking the yarn, the so-called maximum draw ratio of 0.50.
It is necessary to stretch in the range of ~0.85, preferably 0.60 So, 80.

If the stretching ratio is less than the maximum stretching ratio X of 0.50, necking will inevitably occur in the longitudinal direction of the fibers. However, with normal undrawn polyester fibers that do not contain kaolin or metakaolin, necking occurs in the longitudinal direction of the fibers when the draw ratio is less than the maximum draw ratio x0.65. It has spread considerably to the sides. Also, the maximum stretching ratio X0.
If it exceeds 85, thread breakage and single fiber breakage will occur and fluff will easily occur.

In the present invention, each of the two types of filament groups having different single fiber finenesses described above may be stretched at a stretching ratio in a region where the appropriate stretching ratio ranges overlap.

In the present invention, the ratio of the single fiber fineness of the two types of filament groups must be 1.5 times or more. If it is less than 1.5 times, a unique texture that combines a soft texture and a firm waist cannot be obtained. In addition, if the single fiber fineness ratio is increased unnecessarily, the effect on the texture of the filament group with a large single fiber fineness will be overwhelming, resulting in a rough and hard texture, so it is actually not desirable to increase the ratio to 7.0 times or more. .

Although the combination of the number of filaments is not particularly limited, it is best for the texture to be composed of 24 to 48 filaments with a small single fiber fineness and 6 to 18 filaments with a large single fiber fineness. can be obtained.

In the present invention, two types of filament groups with different single fiber finenesses are melted and discharged from the same spinneret, cooled with cooling air according to a conventional method, applied with an oil agent, and then aligned as shown in FIG. It is wound up.

In Fig. 3, B) indicates a small diameter hole, and (B) indicates a large diameter hole.

In the present invention, in order to melt and discharge two types of filament groups with different single fiber finenesses from the same spinneret, a spinneret having discharge holes of the same diameter is used, and the molten polymer is metered with a different gear pump. Alternatively, the size of the pores may be selected at an appropriate ratio and the fineness of the single fibers may be differentiated by utilizing the capillary pressure loss.

The cross-sectional shape of the single fibers may be any shape such as a circular cross-section or an irregular cross-section, or a combination of single fibers of different fineness may have the same or different cross-sectional shapes.

The stretching device used in the present invention is shown in FIG. 4 (al, (bl)
Either the usual bottle and plate type stretching device or the roller plate type stretching device shown in can be used.

In addition, in FIG. 4 (al t (bl), (1) is an undrawn fiber, (2) is a supply roller, (3) is a heat roller,
(4) is a heating bottle, (5) is a hot plate, (6) is a take-up roller, and (7) is a burn.

〔Example〕

The present invention will be specifically explained below using Examples.

Example 1 As a polyester polymer, a polyethylene terephthalate polymer consisting essentially of repeating ethylene terephthalate units containing 1.5 wt% of metakaolin, which was made amorphous by X-ray diffraction by calcining kaolin, was used. The amount of discharge from the spinneret of a hole device as shown in FIG. 3 having 14 holes of 0.30 m and 34 holes of diameter 0.20 m is 33
It was melted and discharged at 290°C at a rate of 1/min. The spun yarn was cooled using a side-blowing type cooling device, with the upper end of the blower placed at 10c+++ below the spinneret, and heated at 25℃65R) (
% air at a speed of 0.57Fl/sec for 1.0m
It was sprayed over the length.

Subsequently, an emulsion-type spinning oil was applied and the spinning was carried out at 1600
Winding in m1 minute, relative viscosity (metacresol, 25℃)
An undrawn polyester mixed fiber yarn of different fineness was obtained with a T/ of 1.554 and a T/ of 73°C.

Table 1 shows the fiber performance of the two filament groups constituting the undrawn polyester mixed fiber yarn.

Table 1 Example 2 The undrawn polyester mixed fiber yarn of different fineness obtained in Example 1 was
After being supplied to the stretching device shown in Figure (at) and pre-stretched by 1.1% between a pair of supply rollers consisting of a rubber roller and a mirror roller and a heating roller, 2. Between the rotation and the take-up roller.
The film was stretched 50 times, heat-treated by running it in contact on a hot plate heated to 145°C, and wound up on a burner at 600 ffl/min.

Table 2 shows the fiber performance of the polyester mixed fiber yarn of different fineness obtained in this way.

When this yarn was knitted into a cylindrical shape and dyed with a disperse dye (Teraseal Blue, manufactured by Ciba Geigy), it showed good level dyeing properties, and no necking was observed in the longitudinal direction of the fibers. Further, the drawing condition was extremely good, and the number of single fiber breaks was 3 to 5 per ton of product. There were no fuzz or loops in the rolled-up barn, and a product of excellent quality could be obtained.

Table 2 [Effects of the Invention] According to the present invention, it is composed of two filament groups with a ratio of single fiber fineness of 1.5 times or more, which was extremely difficult in the conventional method, and it is possible to reduce fluff, loops, and fibers in the longitudinal direction. This makes it possible to easily produce a polyester mixed fiber yarn of different fineness having deep dyeing properties without necking, and the industrial significance of the present invention is extremely high.

[Brief explanation of the drawing]

Figure 1 shows two types of filament groups with different single fiber finenesses when using the method of the present invention (A: filament group with small single fiber fineness, B: filament group with large single fiber fineness)
Fig. 2 is a stress-elongation curve diagram of undrawn fibers of two types of filament groups with different single fiber finenesses in the conventional method, and Fig. 3 is a stress-elongation curve diagram of undrawn fibers used in the method of the present invention. FIG. 4(a) is a front view of a specific example of a spinneret. (bl is a schematic diagram of an example of a drawing device used in the method of the present invention. 1... Undrawn fiber 2... Supply roller 3...
Heat roller 4...Heat pin 5...Heat plate 6...Take-up roller 7 Pan extension Figure 1 Extension - Length 2nd Station 3 ((2) (b) Ratio 4

Claims (1)

[Claims] In a method for producing a polyester mixed yarn of different finenesses, which is composed of two types of filament groups having different single fiber finenesses, kaolin or metakaolin is added in the amount of 0.1 to 5.
．． A polyester polymer containing 0 wt% is melted and discharged from the same melt spinneret so as to simultaneously form two types of filament groups that differ in single fiber fineness by at least 1.5 times, and the undrawn fiber bundle that is drawn and wound is drawn. 1. A method for producing a polyester mixed fiber yarn of different fineness, which comprises supplying the yarn to an apparatus, simultaneously stretching it under the same stretching temperature and stretching ratio, and subjecting it to heat treatment.