JP2016069770A - Sea-island type composite fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fiber in which the shedding of the moisture absorptive ingredient during dyeing is suppressed to a minimum, and the fiber has a good moisture absorptive and desorptive characteristic even after high-pressure dyeing.SOLUTION: Provided is a sea-island type composite fiber having a polyethylene terephthalate whose main repeating unit is ethylene terephthalate, as a sea portion, and a polyether block amide copolymer product as an island portion, and in which the sea/island cross-section area ratio is 30/70 to 95/5.SELECTED DRAWING: None

Description

  The present invention relates to a sea-island type composite fiber having excellent moisture absorption / release properties and antistatic properties.

Fibers made of polyester fiber-forming resins are excellent in yarn strength, dyeability, processability, chemical resistance, and heat resistance, and are widely used in clothing and industrial materials. However, polyester fibers are particularly poor in hygroscopicity among synthetic fibers, and when used as clothing, there are stickiness due to sweating and an increase in humidity in the clothing, and discomfort due to static electricity in a dry environment.
In order to eliminate this unpleasant feeling, for example, an antistatic fiber kneaded with a hydrophilic polymer can be mentioned. However, it is difficult to say that the hydrophilic polymer present in the fiber has a low moisture absorption rate and exhibits moisture absorption / release properties. Furthermore, sufficient antistatic properties are not obtained in a low humidity state.
Further, synthetic fibers in which conductive carbon black is kneaded as antistatic fibers have been developed. However, when conductive carbon black is kneaded, the color of the fibers is limited to almost black, and the design of synthetic fibers excellent in dyeability is severely impaired. Moreover, the synthetic fiber kneaded with the white conductive material has both excellent antistatic properties and whiteness of the fiber, but the white conductive material is expensive and the manufacturing cost becomes high. Furthermore, these fibers are not hygroscopic.
Therefore, Patent Documents 1 and 2 describe a core-sheath composite fiber in which polyester is used as a sheath for imparting hygroscopicity to the polyester fiber, and a polyether / polyamide copolymer having a high water absorption rate is used as a core. .

JP-A-4-361616 JP 2010-189773 A

However, when the sheath is made of polyester, the core sheath is peeled off due to water absorption at the core portion and fiber cracks occur during dyeing when exposed to hot water at high temperature and high pressure. Hygroscopicity and antistatic properties deteriorate.
Accordingly, an object of the present invention is to overcome the above-mentioned problems, minimize the loss of moisture-absorbing components during dyeing, and provide a fiber having excellent moisture absorption / release properties and antistatic properties even after high-pressure dyeing.

  In order to achieve the above-mentioned object, the present invention uses a polyethylene terephthalate whose main repeating unit is ethylene terephthalate as a sea part, a polyether block amide copolymer as an island part, and a sea / island cross-sectional area ratio of 30/70 to 95 / The gist of 5 sea-island type composite fibers.

  According to the sea-island type composite fiber of the present invention, there is no trouble in high-pressure dyeing, and a fiber having excellent moisture absorption / release properties and antistatic properties can be provided even after processing.

Hereinafter, the present invention will be described in detail.
The present invention is a sea-island type composite fiber having polyethylene terephthalate as a sea part and polyether block amide copolymer as an island part.

In the present invention, the sea part uses polyethylene terephthalate whose main repeating unit is ethylene terephthalate. Specifically, it may be homopolyethylene terephthalate or polyethylene terephthalate partially modified with other components such as polyalkylene glycol and organic sulfonic acid metal salt.
Particularly suitable marine polyethylene terephthalates include unmodified polyethylene terephthalate (homopolyethylene terephthalate) and polyalkylene glycol copolymer polyethylene terephthalate.

A suitable example in the case of copolymerizing polyalkylene glycol will be shown.
Polyalkylene glycols of the general formula _{HO (C n H 2n O)} m H ( where, n, m is a positive integer) one represented by, (hereinafter referred to as PEG) n = 2 the polyethylene glycol is generic Most preferred.
Moreover, 50-1000 are preferable and, as for the molecular weight of the polyalkylene glycol used for this invention, More preferably, it is 100-800.
Further, the copolymerization amount of the polyalkylene glycol is preferably 2 to 8% by mass, more preferably about 4 to 6% by mass with respect to the polymer.
If such a polyalkylene glycol is copolymerized, there is an effect of imparting flexibility to the polymer or improving dyeability.

The polyether block amide copolymer used for the island part in the present invention includes, for example, (1) a polyamide unit having a diamine terminal and a polyoxyalkylene unit having a dicarboxylic acid group terminal, and (2) a polyamide having a dicarboxylic acid group terminal. Units, polyether diols, (3) polyamide units having dicarboxylic acid group ends and polyoxyalkylene units having diamine ends (obtained by cyanoethylation and hydrogenation of polyoxyalkylenes having two hydroxyl groups at the α and ω positions) The copolymer is obtained by copolycondensation of a polyamide unit having a reactive end group and a polyether unit having a reactive end group. In the present invention, (2) is preferable, and is represented by the following general formula.
HO— (CO—PA—CO—O—PE—O) _n —H
[Wherein, PA represents a polyamide unit (hard segment), PE represents a polyether unit (soft segment), and n represents a repeating unit. ]
Further, examples of the polyamide unit include 6-nylon, 6,6-nylon, 12-nylon, and the like, but 6-nylon and 12-nylon can be particularly preferably used. Moreover, as a polyether unit, a polyoxyalkylene unit, polyether diol, etc. are mentioned, for example. Of these, polyethylene glycol, polytetramethylene glycol and the like are preferably used.
Further, the mass ratio of the polyamide unit to the polyether unit is preferably 99: 1 to 5:95, more preferably 80:20 to 10:90, and can be effectively used within this range.

  In the sea-island type composite fiber of the present invention, the number of island parts is preferably 5 or more and 40 or less. Within this range, fiber cracks and island part peeling and detachment during high-pressure dyeing are unlikely to occur, the yarn quality is good, and hygroscopicity and antistatic properties are excellent. The number of islands is more preferably 9 or more and 25 or less.

  The sea-island type composite fiber of the present invention has a sea / island cross-sectional area ratio of 30/70 to 95/5. If it is out of this range, sufficient hygroscopicity cannot be obtained, the yarn strength is remarkably lowered, fiber cracks and islands are dropped, and the yarn-making property is also deteriorated. More preferably, the sea / island cross-sectional area ratio is 50/50 to 90/10.

  Moreover, in the fiber cross section, the arrangement of the islands is not particularly defined, but the islands are arranged at a distance of 2% to 40% of the fiber radius from the fiber surface. This range is preferable because fiber cracking and falling off can be prevented without being exposed, and the moisture absorption / release rate related to the comfort of clothing can be increased.

  The thickness (total fineness) of the sea-island composite fiber of the present invention is not particularly limited, but is preferably about 1 dtex to 100 dtex. If the fineness is 1 dtex or more, fiberization is easy, and if it is 100 dtex or less, soft clothing can be produced as a fabric such as a knitted fabric.

  In addition, the sea-island type composite fiber of the present invention may be used in any form as a fiber forming a fabric (knitted fabric), and may be any of multifilament, monofilament, staple, etc. Design yarns such as twisted yarns, air-mixed yarns, core span yarns, and covering yarns may be used. Furthermore, the staple may be a spun yarn.

  Furthermore, the form of the fabric manufactured with the sea-island type composite fiber of the present invention is not specified, and the knitting structure may be each changed structure regardless of weft knitting or warp knitting. The weaving structure may be plain weave (plain), twill weave, satin weaving (satin) or the like, or each changed structure, and dobby, jacquard and the like. It can also be used as a lace, non-woven fabric, or felt.

  In such a fabric form, the basis weight, gauge, etc. are not particularly defined. In addition, the sea-island type composite fiber of the present invention may be used at 100% by mass, or may be used by knitting or weaving with other fibers. Further, it may be used by blending with natural fibers. Although the use ratio is not particularly defined, it is preferable to use the sea-island type composite fiber of the present invention at a ratio of 20% by mass to 100% by mass.

  Fabrics having such functions include materials such as underwear, sweaters, shirts, pantyhose and other clothing, skis, skate fairs, diving suits and other sports clothing, sheets and batting, and food packaging materials. By doing so, it is possible to give these products functions.

  Hereinafter, the present invention will be described in detail with reference to examples. In addition, this invention is not limited to the Example described below. The properties and evaluation of the yarns obtained in the examples and comparative examples of the present invention were determined by the following methods.

<Confirmation of peeling / cracking>
As an auxiliary agent generally used at the time of dyeing, 1.0 g of Sanyo Chemical Co., Ltd. leveling agent Ionette RAP250 and 0.2 mL of acetic acid are added to 1 liter of pure water, and without adding the dye itself that greatly affects the mass increase / decrease, This was used as a treatment agent.
After washing off the oil agent of the cylindrical knitted fabric obtained in the examples and comparative examples, the mass was measured, sealed in a stainless steel pot together with a 50-fold mass treatment agent, and treated in an oil bath at 130 ° C. for 60 min. The sample was sufficiently washed with water and air-dried to obtain a treated sample.
The yarn was extracted from the treated sample, the fiber cross section was collected with a microtome, photographed with an optical microscope, and the presence or absence of peeling and cracking was confirmed.
<Mass reduction rate>
As the equilibrium mass M1 of the treated sample at 20 ° C. and 65% RH and the equilibrium mass M when the oil agent of the tubular knitted fabric is washed away, the mass reduction rate (%) = [(M1−M) / M] × 100 The reduction rate was obtained.
<Antistatic (friction withstand voltage)>
The initial friction withstand voltage and half-life of the treated sample were measured by the JIS L 1094 1997 triboelectric charge decay measurement method. The measurement conditions are as follows.
Friction electrification measurement: Electrostatic tester Friction cloth: Wool Friction direction: Longitudinal direction Laundry treatment: With washing Temperature and humidity: 22 ° C 33% RH
<Hygroscopic rate>
The treated sample was allowed to stand in a room adjusted to 22 ° C. and 40% RH for 1 day, and then the mass was measured to obtain the initial mass. After that, it was put in a constant temperature and humidity chamber adjusted to 30 ° C. and 90% RH, the masses after 12 minutes and 24 minutes were measured, and the mass increase rate from the initial mass was taken as the moisture absorption rate.
<Hygroscopic / absorbable moisture absorption difference ΔMR>
The mass of the treated sample in the absolutely dry state is M0, the equilibrium mass in a 20 ° C. and 65% RH environment is M1, the equilibrium mass in a 30 ° C. and 90% RH environment is M2, and the moisture absorption rate in a 30 ° C. and 90% RH environment The difference in moisture absorption in an environment of 20 ° C. and 65% RH is ΔMR, that is, ΔMR = [(M2−M1) / M0] × 100.

[Example 1]
A base capable of forming a sea-island cross section with polyethylene terephthalate copolymerized with 4.8% by mass of polyethylene glycol having a molecular weight of 600 as a sea part and polyether block amide copolymer (PEBAX (registered trademark) MH1657) as 19 island parts. Was used for melt compound spinning. Extrude each polymer with two extruders adjusted to a temperature higher than the melting point of each polymer, weigh it with a gear pump, associate in the base, pass the discharged yarn through the oil application guide, 1000 m / min The first godet roller that rotates at the first godet roller, and continuously stretched through the second godet roller at a speed adjusted so that the breaking elongation of the obtained yarn is 20 to 60%, and further wound by a winder, A sea-island type composite fiber of 84 dtex / 24f having a sea / island ratio of 80/20 in the fiber cross section was obtained (the island part arranged in the outermost layer is a distance of 27% of the fiber radius from the fiber surface).
Two obtained sea-island type composite fibers were combined and knitted with a cylindrical knitting machine to obtain a cylindrical knitted fabric.

[Example 2]
After obtaining a sea-island type composite fiber of 84 dtex / 24f having a sea / island ratio of 80/20 in the fiber cross section under the same conditions as in Example 1 except that the sea part was changed to homopolyethylene terephthalate, the same as in Example 1 A tubular knitted fabric was created.

[Comparative Example 1]
An 84 dtex / 24 f core-sheath composite fiber having a sheath / core ratio of 80/20 in the fiber cross-section is obtained under the same conditions as in Example 1 except that the base is changed to a base capable of forming a concentric core-sheath cross section. After that, a tubular knitted fabric was prepared in the same manner as in Example 1.

[Comparative Example 2]
An 84 dtex / 24 f core-sheath composite fiber having a sheath / core ratio of 80/20 in the fiber cross-section is obtained under the same conditions as in Example 2 except that the base is changed to a base capable of forming a concentric core-sheath cross section. After that, a tubular knitted fabric was prepared in the same manner as in Example 1.

The evaluation results of Examples 1 and 2 and Comparative Examples 1 and 2 are shown in Table 1.

Both the example product and the comparative product have excellent moisture absorption difference and antistatic property, but the sea-island type composite fibers obtained from Examples 1 and 2 are separated from the sea part and the island part, and the island part is a fiber. While fiber cracks exposed on the surface and falling off were not confirmed, the core-sheath type composite fibers obtained from Comparative Examples 1 and 2 were largely separated at the core part and the sheath part. Further, the fibers obtained from the examples had a higher moisture absorption rate after 12 minutes and 24 minutes than the comparative products, and the example products had a better moisture absorption rate than the comparative products.
Moreover, when the normal high-pressure dyeing | staining process was carried out to the cylindrical knitted fabric obtained from these Examples and the comparative example, the Example goods do not have peeling of a sea part and an island part, and are excellent also in antistatic and moisture absorption. However, the comparative example product peeled off the core and sheath, and had antistatic properties, but was less hygroscopic than the example product.

Therefore, when the sea-island type composite fiber of the present invention is used as a garment, unpleasant static electricity hardly occurs, and unpleasant humidity in the garment can be quickly released to make the garment a comfortable environment. .
Therefore, the fabric comprising the sea-island type composite fiber of the present invention includes clothing such as underwear, sweaters, shirts and pantyhose, sports clothing such as skis, skatewear, and diving suits, bedding such as sheets and batting, and food packaging. It can be suitably used for materials such as materials.

Claims (1)

Sea-island type composite fibers having polyethylene terephthalate whose main repeating unit is ethylene terephthalate as the sea part, polyether block amide copolymer as the island part, and sea / island cross-sectional area ratio of 30/70 to 95/5.