JP2001123330A - Split type polyester conjugate fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new split type polyester conjugate fiber which has excellent operation production stability and can easily give ultrafine fibers having a single fiber fineness of <=0.3 dtex. SOLUTION: This split type polyester conjugate fiber comprises a component A and a component B, in which the component B has a fiber cross-sectional shape wherein the component B is divided into plural divisions with the component A, and in which a trimethylene terephthalate-based polyester and a polyester containing a polyetherester and/or a polyoxyalkylene glycol are disposed as the component A and the component B, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a splittable polyester composite fiber having a fiber cross-sectional shape in which one component is divided into a plurality by the other component. More specifically, the present invention relates to a splittable polyester conjugate fiber that can easily and efficiently provide a polyester fiber having an ultrafine size by treating with an aqueous alkaline solution.

[0002]

2. Description of the Related Art Conventionally, an alkali-soluble component is removed from a splittable conjugate fiber arranged so that an alkali-soluble component is divided into a plurality of alkali-insoluble components (or alkali-insoluble components). It is widely known that, by doing so, an ultrafine fiber yarn can be obtained, and a cloth exhibiting a silky feeling can be obtained by treating the composite fiber with a fabric and then performing alkali treatment (Japanese Patent Application Laid-Open No. 54-54). 13862, JP-B-47-47532, JP-A-5-98
No. 11).

Further, the ultrafine polyester fiber obtained by such a method has a high melting point, a high strength, a high Young's modulus,
Because of its excellent properties such as good electrical properties and chemical resistance, it is expected to be applied to silk-like woven and knitted fabrics, sports clothing, filters, various other clothing and industrial fields.

[0004] In producing such a splittable conjugate fiber, if the alkali weight reduction treatment is performed under severe conditions, for example, at around 100 ° C, even the alkali-insoluble components can be obtained under the influence of the alkali weight reduction treatment. The thickness of the fiber becomes non-uniform, the physical properties are deteriorated, and problems occur in terms of safety and cost.

[0005] Accordingly, in order to make it possible to decompose and remove the alkali-soluble component by the alkali weight-reducing treatment under milder conditions (for example, around 50 ° C), the alkali-soluble component and the alkali-sparing component (or alkali non-soluble component) are removed. The dissolution rate difference between the alkali-soluble component (or the soluble component) and the alkali-soluble component (or the alkali-insoluble component) when the alkali-soluble component is dissolved and removed. In some cases, the poorly soluble alkali components do not adhere to each other). However, polyester composite fibers that can satisfy all of these characteristics have not yet been proposed.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and has as its object to provide excellent stability in operation production and a single fiber fineness of 0. An object of the present invention is to provide a novel splittable polyester composite fiber capable of obtaining an ultrafine fiber of 0.3 dtex or less.

[0007]

Means for Solving the Problems In view of the above prior art, the present inventors have made intensive studies and as a result, when polytrimethylene terephthalate is arranged in a part of the splittable conjugate polyester fiber, excellent characteristics are exhibited. And found that the present invention was completed. That is, the purpose of the present invention is
And a component B, wherein the component B is a splittable polyester conjugate fiber having a fiber cross-sectional shape divided into a plurality of parts by the component A, wherein a polyester having a trimethylene terephthalate unit as a main repeating unit is used as the component B. Then, as the component A, a polyester composition containing a polyetherester comprising a dicarboxylic acid component and a polyoxyalkylene glycol component and / or a polyoxyalkylene glycol in an amount of 3 to 10% by weight based on the component A is provided. It can be achieved by a split polyester composite fiber characterized by the following.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The conjugate fiber of the present invention comprises a component A and a component B, and the component B has a fiber sectional shape divided into a plurality by the component A. Here, as the component A, a polyester composition containing a polyetherester and / or a polyoxyalkylene glycol composed of a dicarboxylic acid component and a polyoxyalkylene glycol component in an amount of 3 to 10% by weight based on the component A is used. It is necessary to use it, and the content is preferably 4 to 9% by weight, more preferably 5 to 8% by weight.

If the content is less than 3% by weight, a sufficiently high alkali weight loss rate cannot be obtained, and 0.3 dte
It is also difficult to produce ultrafine fibers of x or less. Meanwhile, 1
When the content exceeds 0% by weight, the gas generated by the thermal decomposition of the contained components causes the yarn breakage, and the spinning property deteriorates.

The dicarboxylic acid component of the polyetherester in the component A includes aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenoxyethanedicarboxylic acid, adipic acid, sebacic acid, and the like. Examples thereof include aliphatic and alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid.

The polyoxyalkylene glycol includes polyoxyethylene glycol, polyoxypropylene glycol, polyoxybutylene glycol,
Examples thereof include polyoxypentylene glycol, polyoxyhexylene glycol, and random or block copolymers thereof, and among them, polyethylene glycol is preferable. Further, the molecular weight of the polyoxyalkylene glycol is in the range of 1,000 to 50,000 since the effect of increasing the rate of alkali weight loss is further improved.
It is preferable that it is especially 3000-20000.

The molecular weight of the polyetherester composed of the above components is preferably 10,000 to 8 from the viewpoint of streak dispersibility and spinnability of the polyetherester component in the conjugate fiber.
It is preferable that 4 to 50 dicarboxylic acid components are copolymerized per 1 molecule of the polyetherester.

Any of the conventionally known methods can be employed to produce the above-mentioned polyetherester, for example, by reacting the acid anhydride or acid chloride of the dicarboxylic acid with the polyoxyalkylene glycol. .

A small amount of a low molecular weight glycol such as ethylene glycol or tetramethylene glycol may be copolymerized as long as the object of the present invention is not impaired.

On the other hand, the polyester used for the component A is not particularly limited, but is the same as the polyester used for the component B described below in terms of good spinning properties during melt spinning or good handling of the conjugate fiber. It is preferable to use a polytrimethylene terephthalate-based polyester.

In the present invention, the polyester used as the component B is a polytrimethylene terephthalate-based polyester having a trimethylene terephthalate unit as a main repeating unit, as long as the object of the present invention can be achieved. May be a polyester in which a part of the polyester is substituted with another difunctional carboxylic acid component,
The polyester in which a part of the trimethylene glycol component is substituted with another diol component may be used, and both components may be substituted. Here, in the present invention, "main" means that the component is based on all components,
It means that it occupies 85% or more.

The bifunctional carboxylic acids other than the terephthalic acid component include, for example, isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenoxyethanedicarboxylic acid, adipic acid, sebacic acid,
Aromatics, such as 1,4-cyclohexanedicarboxylic acid,
Aliphatic and alicyclic difunctional carboxylic acid components can be mentioned. Examples of other diol compounds other than the trimethylene glycol component include aromatic glycols such as ethylene glycol, tetramethylene glycol, hexamethylene glycol, cyclohexane-1,4-dimethanol, neopentyl glycol, bisphenol A and bisphenol S. , Aliphatic and alicyclic diol components.

In the present invention, a split fiber comprising a poorly soluble alkali component is obtained by the difference in the alkali weight loss rate between the component A and the component B, and the larger the solubility difference, the more desirable. Is 10 of B component
The ratio is preferably at least 20 times, more preferably at least 20 times. However, if the polyester constituting the component B is a polytrimethylene terephthalate-based polyester, the above-described weight loss rate ratio can be achieved.

In order to increase the alkali weight loss rate of the component A, an anionic surfactant may be added to the component A, and 0.2 to 2% by weight based on the component A, In particular, when 0.4 to 1% by weight is blended, it is possible to achieve a high level of both the spinning property and the effect of improving the alkali weight loss rate.

The composite shape of the alkali-soluble component A and the alkali-poorly-soluble component B and the cross-sectional shape of each component may be such that the component B is divided into a plurality of components by the component A. Optional, some examples are shown in FIG.
(A) to (i) are shown.

In FIG. 1, A is a polyester composition (component A), and B is a polyester (component B). (A) to (c) are splittable conjugate fibers in which component B is split into 16 by component A. (D) is a component A
Is a sea-island type splittable conjugate fiber in which component B is an island, and component B is divided into 26 by component A.
(E) and (f) are splittable conjugate fibers having a flat cross-sectional shape, and (g) to (i) are obtained by coating the outer peripheral portions of (a) to (c) with the component A, respectively.

The above splittable conjugate fiber can be formed into a very fine fiber and a space between the fibers by alkali treatment after forming the cloth, so that the cloth having a bulky and soft feel can be obtained. Suitable to get.

The composite ratio of the component A and the component B in the splittable polyester composite fiber is such that (component A: component B) is weight from the viewpoint of achieving both the ease of division by alkali treatment and the physical properties of the composite fiber. (80:20) ~
(2:98), preferably (60: 4).
0) to (5:95).

In the splittable polyester conjugate fiber of the present invention, when the constitutional unit composed of the component B is 0.3 dtex or less and the number of the constitutional units is 16 or more, especially 24 or more, the effect obtained is remarkable. Is preferable.

To produce the splittable polyester composite fiber of the present invention described above, any conventionally known composite spinneret and composite spinning apparatus can be used, and any spinning conditions can be adopted without any trouble. For example, 500-2500m /
Melt spinning, stretching and heat treatment at a speed of 150 minutes
A method in which melt spinning is performed at a speed of 0 to 5000 m / min, and stretching and false twisting are performed simultaneously or successively, a method in which melt spinning is performed at a high speed of 5000 m / min or more, and a drawing step is omitted depending on the application. Can be adopted. Further, the obtained fiber or a woven or knitted fabric produced from this fiber may be heat-treated at a temperature of 100 ° C. or more to improve the stability of the structure, or may further be used together with a relaxation heat treatment if necessary. .

[0026]

According to the present invention, at least one of the polyetherester and the polyoxyalkylene glycol blended in the component A of the present invention is present in a dispersed state instead of being dissolved in the polyester composition. Since the fibers are dispersed in the form of streaks in the fiber axis direction when formed into a conjugate fiber, an effect of increasing the alkali weight loss rate can be obtained.

Therefore, according to the present invention having such characteristics, even when the amount of the third component present in the component A is reduced, a favorable alkali weight reduction rate can be maintained, and the process stability during the yarn production can be maintained. It has an extremely remarkable effect that polytrimethylene terephthalate fiber of ultrafineness can be easily obtained under mild conditions without impairing the properties, and its industrial significance is extremely large.

[0028]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited by these examples.

Examples 1 and 2 As component A, polyethylene terephthalate having an intrinsic viscosity of 0.63 containing 6% by weight of a polyetherester compound shown in Table 1 was used. Using trimethylene terephthalate, composite spinning and drawing according to a conventional method,
A sea-island composite fiber as shown in FIG. 1 (d) (provided that the composite ratio is 50/50, 83.25 dtex (75 de) / 20)
fi) was obtained.

A plain fabric is formed using the obtained composite fiber,
The alkali weight reduction treatment was performed in an aqueous sodium hydroxide solution (concentration: 30 g / liter) at the boiling temperature. Table 1 shows the weight loss rates required for the division.

[0031]

[Table 1]

As is clear from the above table, Examples 1 and 2
In both cases, it can be seen that the alkali weight loss progresses quickly and the hardly soluble alkali component B (polytrimethylene terephthalate) can be divided into ultrafine fibers without decomposing much (that is, at a low weight loss rate).

Comparative Example 1 The same operation was performed as in Example 1, except that the blending amount of the polyetherester compound was changed from 6% by weight to 1% by weight. The alkali weight loss required to split component B was 67%.

Comparative Example 2 In Example 1, the amount of the polyetherester compound was changed from 6% by weight to 12%.
The same operation was performed except that the amount was changed to wt%, but thread breakage occurred during spinning of the conjugate fiber, and the process stability deteriorated.

[Examples 3 and 4] In Example 2, sodium alkylsulfonate having an alkyl group having 8 to 20 carbon atoms and having an average carbon number of 14 as an anionic surfactant was added to the component A. The same operation was performed except that the amounts shown in Table 2 were blended. Table 2 shows the results.

[0036]

[Table 2]

As is clear from the above table, when the anionic surfactant is blended in the component A, the alkali weight loss required for dividing the component B is close to 50%, and the alkali weight loss of the component B itself is too small. You can see that it has not happened.

[Brief description of the drawings]

FIG. 1 is an enlarged cross-sectional view showing an example of a splittable polyester conjugate fiber of the present invention.

[Explanation of symbols]

 A component A B component B

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4L041 BA04 BA05 BA11 BA12 BA13 BA16 BA34 BA42 BD14 CA06 CA08 CA16 CB17 DD01 DD11 DD14 DD18 DD21 EE06 EE15 EE20

Claims (2)

[Claims] 1. A composition comprising a component A and a component B,
Is a split-type polyester composite fiber having a fiber cross-sectional shape divided into a plurality by the component A, wherein the component B
A polyester having a trimethylene terephthalate unit as a main repeating unit, and a polyetherester comprising a dicarboxylic acid component and a polyoxyalkylene glycol component and / or a polyoxyalkylene glycol as a component A. 3 to 1
A splittable polyester conjugate fiber, comprising a polyester composition containing 0% by weight. 2. The conjugate fiber according to claim 1, wherein component A contains 0.2 to 2% by weight of an anionic surfactant based on the total weight of component A.