JP2000328369A - Polyester multifilament containing regenerated polyester - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyester multifilament having good hue without dyeing specks in spite of its high content of a regenerated polyester. SOLUTION: This polyester multifilament comprises a raw material polyester A and a regenerated polyester B, contains regenerated polyester and is spun from the same spinneret 1. The core component is the regenerated polyester B and the sheath component is the raw material polyester A. The weight ratio of the core component and the sheath component (the core/the sheath) is 20/80-80/20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyester fiber using a regenerated polyester, and to a polyester multifilament which does not cause staining spots.

[0002]

2. Description of the Related Art Polyethylene terephthalate (PET)
And other polyesters have a high melting point, chemical resistance, and low cost, so that they are widely used not only for fibers but also for films, molded products, and the like.

[0003] These polyester products are discarded after use. However, when they are burned, high heat is generated, and there is a problem that the incinerator is greatly damaged and its life is shortened. Since it does not decompose, it remains permanently, which is also a problem from an environmental point of view.

[0004] In terms of resource reuse and environmental problems, recyclability has been demanded in various fields and materials.
Even for polyesters, which are used in large quantities and are expected to increase significantly in the future, attempts to recycle PET bottles and other molded products into chips, and recycle them into fibers, films, and molded products have been attempted. Has begun.

[0005] As for polyester fibers, attempts have been made to produce fibers, films and molded products again by cutting the fibers into a predetermined size, melting and chipping. In that case, fibers of various forms, degrees of polymerization and color tones are melt mixed.

Among the colors, recycled polyester is made of fiber,
When used as a film, molded product, etc., it is an important quality item.If the color tone of the raw material fiber before melting is poor, the color tone of the recycled polyester will also be worse, and the fiber produced from this recycled polyester is dyed in addition to the color tone. In this case, there is a problem that the use is limited because stained spots also occur.

Therefore, it has been proposed to mix not only recycled polyester but also raw polyester and recycled polyester to form a multifilament. For example, there have been proposed mixed filaments obtained by mixing raw PET and regenerated polyester at the stage of chips before melting, and kneading separately melt-extruded PET and regenerated polyester in a nozzle pack.

However, in the case of this mixed filament, there is a problem that color spots such as stain spots occur when the quality of the recycled polyester portion fluctuates or when the mixture ratio of the recycled product increases.

[0009]

An object of the present invention is to provide a high-quality polyester multifilament which solves the above-mentioned problems and does not cause color spots such as stain spots even if it contains recycled polyester. It is a technical issue.

[0010]

Means for Solving the Problems The present inventors have studied to solve the above-mentioned problems, and as a result, have reached the present invention.
That is, the present invention relates to a polyester multifilament containing a recycled polyester, comprising a raw polyester A and a recycled polyester B, spun from the same spinneret, the core component being the recycled polyester B, and the sheath component being the raw polyester A. And the weight ratio of the core component and the sheath component (core / sheath) is 20/80.
The present invention provides a recycled polyester-containing polyester multifilament characterized by being 80 to 20/80.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The recycled polyester-containing polyester multifilament of the present invention has a core component composed of recycled polyester B and a sheath component composed of raw material polyester A, and has a weight ratio (core / sheath) of the core component and the sheath component of 20/80 to 80/20, More preferably, it is 55 / 45-75 / 25.

When the recycled polyester B is disposed in the sheath component or when the proportion of the recycled polyester exceeds 80% by weight,
Color spots such as dye spots occur on the entire filament, resulting in low quality. When the content of the recycled polyester B is less than 20% by weight, stable discharge from the extruder cannot be performed, and the fineness distribution is deteriorated, and the operability is deteriorated.

The raw material polyester and recycled polyester in the present invention are mainly composed of polyethylene terephthalate (PET) and polybutylene terephthalate (P).
BT), those made of polypropylene terephthalate (PPT), aliphatic polyesters, and the like. PET is most preferable in consideration of fiber strength and economy.

These polyesters may be those obtained by copolymerizing the third component as long as the objects and effects of the present invention are not impaired. Examples of such copolymerization components include aromatic dicarboxylic acids such as isophthalic acid and naphthalenedicarboxylic acid, aliphatic dicarboxylic acids such as adipic acid, sebacic acid, and azelaic acid; and diols such as diethylene glycol and 1,4-butanediol. Compounds can be mentioned.

The recycled polyester used in the present invention means that the raw polyester is polymerized and then directly spun without solidification.
Fibers, films, non-woven fabrics, solids, molded products are regenerated by spinning and forming films by forming chips or by melting and solidifying chips by cooling and solidifying. , Films, non-woven fabrics, solids, molded products, etc. are cut, pulverized and melted to obtain polymers.

In the polyester multifilament of the present invention, as long as the effects of the present invention are not impaired, both the raw material polyester A and the regenerated polyester B prevent oxidation of a dulling agent such as titanium oxide and a hindered phenol compound. Agents, other pigments, additives and the like may be blended.

Next, a method for producing a polyester multifilament of the present invention will be described with reference to the drawings. The polyester multifilament of the present invention has a length of 2000 m.
/ P wound up as semi-undrawn yarn by high-speed spinning
OY method, or a method in which melt spinning is performed once by high-speed spinning of 2000 m / min or more or low-speed spinning of less than 2000 m / min, and a stretched heat treatment is performed on the wound yarn. The filament is obtained by a method, and may be manufactured by any method.

FIG. 1 is a process diagram showing the steps from the spinning to the winding of the undrawn yarn in the case where the undrawn yarn is once wound up and then drawn in a separate step.

Using a conventional composite spinning apparatus, a raw material polyester A is disposed as a sheath component, and a recycled polyester B is disposed as a core component.
Spinning temperature 260-310 ° C, spinning speed 1000-500
It is melted and discharged from the spinneret 1 at 0 m / min. The eluted conjugate fibers are cooled by applying cooling air in the cooling device 2, then oiled by the oiling device 3, bundled by the focusing guide 4, and then supplied to the entanglement device 5 to be entangled. Is given. Subsequently, it is taken up via the take-up rollers 6 and 7 and wound up by the winder 8.
Then, with a stretching machine that is usually used, a magnification of 1.3 to 3.
Stretching is performed nine times at a stretching speed of 400 to 900 m / min.

[0020]

Next, the present invention will be described specifically with reference to examples. In addition, the measurement and evaluation in an Example were performed as follows. (1) Intrinsic viscosity A weight mixture of phenol and ethane tetrachloride is used as a solvent,
It was measured at 20 ° C. (2) Dyeing Spot The obtained yarn was knitted in a tube and dyed, and the dyeing spot was visually judged and evaluated in three steps. ：: good Δ: slight spots ×: large spots were generated The dyeing conditions were 2.0% owf of Terasil Nevy Blue SGL (Bayer's original yarn dye), using a dyeing solution having a bath ratio of 1:50. Staining was performed at 99 ° C. for 60 minutes by a conventional method. (3) Strength and elongation Using a tensile tester AG-100G manufactured by Shimadzu Corporation,
Using a sample with a yarn length of 100 mm, pulling speed 500 mm
/ Min and the value at the time when the yarn was broken was measured.

Examples 1 to 3 and Comparative Examples 1 and 2 As polyester A as a sheath component, P having an intrinsic viscosity of 0.68 was used.
Using ET, chips dried by a conventional method were supplied to an extruder A at 290 ° C. Recycled polyester B as the core component, intrinsic viscosity of 0.68 mainly recycled from PET bottles
Using a recycled PET of 29, chips dried in a usual manner
It was fed to extruder B at 0 ° C. Then, the mixture was supplied to a composite spinning apparatus so as to have a core-sheath weight ratio as shown in Table 1, and spinning was performed according to the process shown in FIG. Spinneret 1
Are provided with 48 spinning holes having a hole diameter of 0.25 mm. The bundle of yarns is cooled by an air flow in the cooling device 2 and passed through the oiling device 3 to have an adhesion amount of 0.5 wt%. After the oil agent was applied as described above, the bundle was converged by the converging guide 4 and entangled, the yarn was taken up by a roller at a spinning speed of 3500 m / min and wound up by a winder 8. The obtained yarn is 2
30d / 48f, and there was no defect due to fluff or broken single yarn. Next, this was subjected to 700 m
Per minute to obtain a multifilament having a composite structure of 150d / 48f.

Comparative Example 3 The same procedure as in Example 1 was carried out except that the raw material PET and the regenerated PET were mixed and melt-kneaded at the stage of the chips before melting, and then spun from a single-hole spinneret.

Comparative Example 4 Except that the raw material PET was supplied to an extruder A, the regenerated PET was supplied to an extruder B, and both were kneaded in a nozzle pack and spun from a single-hole spinneret. It carried out like Example 1.

Comparative Example 5 The same procedure as in Example 1 was carried out except that raw material PET was used as the core component and recycled PET was used as the sheath component.

Table 1 shows the evaluations of the strength, elongation, and unevenness of the fibers obtained in Examples 1 to 3 and Comparative Examples 1 to 5.

[0026]

[Table 1]

As is clear from Table 1, the fibers obtained in Examples 1 to 3 were excellent in color tone without generation of dyed spots, and had values with no problem in strength and elongation. On the other hand, in the fiber of Comparative Example 1, since the ratio of the recycled PET in the core portion was too large, stained spots occurred. In Comparative Example 2, the ratio of the recycled PET in the core portion was too small, and the ejection spots were generated. Operability was poor. In addition, the fibers of Comparative Examples 3 and 4 consisted of raw PET and recycled P.
Since it was a single fiber kneaded with ET, the fiber had many occurrences of staining spots. Moreover, since the fiber of Comparative Example 5 used recycled PET for the sheath part, many stain spots were generated on the fiber surface and the quality was inferior.

[0028]

Since the polyester multifilament of the present invention is a composite fiber using recycled polyester as a core component, it does not cause staining spots, is excellent in color tone, and can be used for various purposes. In addition, it can be obtained without any operational problems.

[Brief description of the drawings]

FIG. 1 is a partially schematic process diagram showing one example of a method for producing a polyester multifilament of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Spinneret 2 Cooling device 3 Oiling device 4 Focusing guide 5 Entangling device 6, 7 Take-up roller 8 Winding machine

Claims (1)

[Claims] 1. A polyester multifilament containing a recycled polyester, comprising a raw polyester A and a recycled polyester B, spun from the same spinneret, wherein the core component is the recycled polyester B and the sheath component is the raw polyester A. Yes, weight ratio of core component and sheath component (core /
A polyester multifilament containing recycled polyester, wherein the sheath is 20/80 to 80/20.