JP2628502B2 - Composite elastic yarn and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel composite elastic yarn. More specifically, it is a latent elastic yarn and a polyurethane elastic yarn that can be spun at high speed (hereinafter abbreviated as spandex).
About. Here, the latent elastic yarn refers to a yarn that can exhibit rubber-like elastic properties only by water treatment.

[0002]

2. Description of the Related Art Polyurethane elastic yarns have been used in various applications because of their excellent physical properties, but have problems in yarn handling and operability in post-processes such as various yarn processing and knitting.

[0003] In order to improve the handleability in the subsequent process, there is a method of reducing the elongation of the urethane elastic yarn (for example, a method of covering the urethane elastic yarn with nylon or the like). Furthermore, Japanese Patent Publication No. 55-8606 discloses a composite fiber comprising a water-soluble polyamide mainly composed of polybis (propoxy) ethane adipamide and a polyurethane, and having a latent rubber-like elasticity capable of exhibiting rubber-like properties by water treatment. Is disclosed.

[0004] On the other hand, spandex is used for various applications because of its excellent physical properties.
At present, it is inferior to other general-purpose polymers (for example, nylon, polyester, etc.) (for example, the spinning speed of spandex is about 500 m /
Minutes). This is described in the Journal of the Fiber Society of Japan, Vol. 47, P581 (1
This is because, as described in 991), when the spinning speed is increased, the yarn is likely to be oriented and the yarn becomes hard, and it is easy to wind up due to the large elongation of the yarn. Therefore, at present, breakthroughs for achieving higher speeds beyond the low modulus constraint inherent to spandex have not yet been performed.

[0005]

Among these, the method of covering urethane elastic yarn with nylon or the like requires the use of a special device and has a problem that the production speed is extremely slow.

Furthermore, composite elastic fibers having a sheath component made of a water-soluble polyamide and a core component made of a polyurethane have a low yield in the synthesis of a diamine having an ether bond, which is a raw material of the polyamide, and have a low heat resistance. Stability and melt stability were unstable and spinning became difficult, so that it was not put to practical use.

Accordingly, an object of the present invention is to provide a fabric in the same manner as ordinary synthetic fibers (such as nylon), and to almost completely recover the properties as a urethane elastic yarn by a water treatment process such as a scouring or dyeing process. Another object of the present invention is to provide a novel composite elastic yarn. Another object of the present invention is to provide a method for producing a spandex which can be wound at a speed equivalent to that of a general synthetic fiber (eg, nylon) and has a low modulus of the obtained yarn, is industrially advantageous and inexpensive.

[0008]

Means for Solving the Problems The present inventors have made intensive studies to achieve the above object, and have completed the present invention.

That is, in the composite elastic yarn of the present invention, the polyurethane and the water-soluble polyester have a fiber cross-sectional area ratio (composite ratio) of 1
/ 2 to 50/1 and the water-soluble polyester is a conjugate fiber exposed on the fiber surface, and the water-soluble polyester is an aromatic dicarboxylic acid having a sulfonate as an acid component and / or an ester thereof. 5 to 20 mol% of the derivative (A component), 55 mol% or more of the aromatic dicarboxylic acid excluding the A component and / or its ester-forming derivative (B component), and the alicyclic dicarboxylic acid and / or
Or its ester-forming derivative component (component C) and its aliphatic dicarboxylic acid and / or its ester-forming derivative component (D
Component C) and the above component C and component D are 0 mol%.
It satisfies the relationship of ≦ C + 4 × D ≦ 40 mol%, and the glycol component is composed of 50 mol% or more of ethylene glycol.

In the production method of the present invention, the aromatic dicarboxylic acid having a sulfonic acid salt as an acid component and / or an ester-forming derivative thereof (component A) is 5 to 20 mol%;
55 mol% or more of the aromatic dicarboxylic acid and / or its ester-forming derivative (component B) excluding the components, and the alicyclic dicarboxylic acid and / or its ester-forming derivative (component C) and the aliphatic dicarboxylic acid and / or The ester-forming derivative (D component), wherein the C component and the D component satisfy the relationship of 0 mol% ≦ C + 4 × D ≦ 40 mol%, and the glycol component is from 50 mol% or more of ethylene glycol. The water-soluble polyester and the polyurethane are joined together, the water-soluble polyester is exposed on the fiber surface, and the fiber cross-sectional area ratio (composite ratio) of polyurethane / water-soluble polyester is in the range of 1/2 to 5/1, and the spinning speed is adjusted. Winding at a speed of 1,000 to 3,500 m / min and a draw ratio of 1.5 to 5 at the time of spinning with or without heat, and the composite ratio is 6 If the range of 1 to 50/1, characterized in that the take Maki below state under stretching ratio 1.4 without heat at a spinning speed of 500～3,000M / min.

Hereinafter, the present invention will be described in detail. The polyurethane as the core component constituting the present invention refers to a thermoplastic polyurethane or a crosslinked polyurethane. Here, the thermoplastic polyurethane refers to a polymer obtained by reacting a polymer diol with an organic diisocyanate and a chain extender, and which can be melt-spun. For example, as a polymer diol, having a hydroxyl group at both ends, polytetramethylene glycol having a molecular weight of 500 to 5000, ether polyols such as polypropylene glycol, polyhexamethylene adipate, polybutylene adipate, polycarbonate diol, polycaprolactone diol and the like Glycols such as ester-based polyols alone, or mixtures thereof, and copolymerized diols may be used.

Examples of the chain extender include 1,4-butanediol having a molecular weight of 500 or less, ethylene glycol, propylene glycol, and bishydroxyethoxybenzene.

The organic diisocyanate includes tolylene diisocyanate (TDI), 4,4'-diphenylmethane diisocyanate (MDI) or a non-yellowing diisocyanate such as 1,6-hexamethylene diisocyanate, and a mixture thereof.

The hardness of the polyurethane polymerized from these components by a known method is 75 to 98 in JIS-A hardness.
Is preferable. If the hardness is less than 75, the resulting composite yarn is inferior in resilience and insufficient in practical heat resistance. vice versa,
If the hardness exceeds 98, the recoverability of the polyurethane itself is inferior and the recoverability of the composite yarn cannot be expected unless the crimped structure is used, and the range of optimum spinning conditions for the polyurethane is undesirably small. Preferably, the range of 82 to 95 is good.

It is also preferable to add known titanium oxide, an ultraviolet stabilizer, an ultraviolet absorber, an antibacterial agent and the like to the polyurethane of the present invention, if necessary.

In the case where further heat resistance and further recoverability as a composite yarn are required, a crosslinked polyurethane obtained by reacting a polyisocyanate with the above polyurethane may be disposed in the core component. As the production method, a method proposed by us (Japanese Patent Publication No. 58-46573), that is, a method in which a polyisocyanate is added to and mixed with a molten thermoplastic polyurethane to complete the allophanate cross-linking during or after spinning is used. good.

The polyisocyanate is composed of a polyol component and an isocyanate component, and has 2
It is a compound having at least two isocyanate groups. As the polyol component, in addition to the above-mentioned diols having a molecular weight of 500 to 4000 used for the synthesis of polyurethane, those obtained by mixing a diol and a triol to have an average functionality of 2 to 3, or a synthetic polyol having a functionality of 2 to 3 It can be suitably used. On the other hand, as the isocyanate component, the diisocyanate used in the synthesis of polyurethane, a trimer of an organic diisocyanate, a reaction product of trimethylolpropane and an organic diisocyanate, or an isocyanate having a functionality of 2 to 3 (for example, , Carbodiimide-modified isocyanate) or a mixture thereof.

The reaction between the above two components can be carried out by a known method. In this case, it is preferable to carry out the reaction so that the isocyanate group content becomes excessive. Of course, this amount
It is appropriately selected depending on the desired physical properties such as heat resistance and recoverability, and the polyol to be used.

The amount of the polyisocyanate to be added is usually preferably in the range of 5 to 40% by weight based on the mixture of the polyurethane used as the core component and the polyisocyanate. The amount of addition varies depending on the NCO group content and type of the polyisocyanate used, but if the amount exceeds 40% by weight, mixing is uneven and spinning becomes unstable, and the mechanical properties of the yarn are also unsatisfactory. It is not preferable because only things are obtained. Conversely, if it is less than 5% by weight, the desired heat resistance cannot be obtained, which is not preferred, and the range is preferably 10 to 30% by weight.

In this way, a cross-linked structure mainly containing allophanate cross-links is formed in the polyurethane in the core component. In this case, when the crosslinked structure is mainly formed by burette bonding, spinnability is extremely deteriorated, which is not preferable. That is, since the formation rate of burette cross-linking is higher than that of allophanate cross-linking, the viscosity of the system during spinning increases, and stable spinning tends to be impossible.

The water-soluble polyester used in the present invention has the following composition.

Aromatic dicarboxylic acid having a sulfonic acid salt of an acid component and / or an ester-forming derivative thereof (Component A)
Preferred are those having a sulfonic acid alkali metal base, for example, 4-sulfoisophthalic acid, 5-sulfoisophthalic acid, sulfoterephthalic acid, 4-sulfophthalic acid, 4-sulfonaphthalene-2,7-dicarboxylic acid,
An alkali metal salt such as-[4-sulfophenoxy] isophthalic acid or an ester-forming derivative thereof is used, and 5-sulfoisophthalic acid sodium salt or an ester-forming derivative thereof is particularly preferable. These sulfonic acid group-containing dicarboxylic acids and / or ester-forming derivatives thereof are used in an amount of from 5 to 20 mol%, preferably from 6 to 12 mol%, based on the total dicarboxylic acid component from the viewpoint of water solubility and water resistance. Good range. If the amount is less than 5 mol%, the solubility in water becomes poor. On the contrary, if it exceeds 20 mol%, troubles during polymerization and poor operability at the time of chipping are caused, and the resulting polymer is easy to handle. This is not preferred because it has an adverse effect on thermoplasticity and the like.

The aromatic dicarboxylic acid and / or its ester-forming derivative (component B) excluding the above-mentioned component A include terephthalic acid and / or its ester-forming derivative (component B1) and isophthalic acid and / or its ester-forming derivative ( Component B2) is preferred from the viewpoints of availability of raw materials, industrialization and good mechanical properties, and more preferably 55% by mole or more of all dicarboxylic acids. If the amount is less than 55 mol%, the physical properties of the obtained polymer, particularly the melt heat stability and the heat resistance are inferior. Further, the molar ratio of the B1 component / B2 component is 2/8.
８8/2 is preferred in terms of making the polymer amorphous.

The alicyclic dicarboxylic acid and / or its ester-forming derivative component (component C) includes 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 1,3
-Cyclopentanedicarboxylic acid, 4,4'-bicyclohexyldicarboxylic acid, or the like, or an ester-forming derivative thereof is used.

Further, examples of the aliphatic dicarboxylic acid and / or its ester-forming derivative component (D component) include adipic acid, sebacic acid and azelaic acid. The above C
Component and D component are 0 mol% ≦ C + 4 × D ≦ 40 mol%
(C and D are the mole fractions of the C or D component with respect to the total acid components) It is necessary not only to prevent blocking of the obtained polymer but also from the viewpoint of water resistance. This means that the D component is, for example, 20 mol% and the C component is 0 mol%.
In the case of, the glass transition temperature of the obtained polymer is about room temperature, the handling property is poor, and the physical properties of the polymer are inferior.

On the other hand, as the diol component, ethylene glycol is used in an amount of 50 mol% or more based on the total glycol component from the viewpoint of the spinnability of the polyester copolymer. In addition, as a glycol component, other than ethylene glycol, mechanical properties, 1,4-butanediol, neopentyl glycol, and the like within a range that does not adversely affect heat melting stability and the like.
1,4-cyclohexanedimethanol, diethylene glycol, triethylene glycol, polyethylene glycol and the like may be used in combination.

As the polymerization method of the copolymerized polyester used in the present invention, various ordinary methods can be used. For example, a transesterification reaction of dimethyl ester of dicarboxylic acid and glycol is performed, and after methanol is allowed to flow,
A method of performing polycondensation under a reduced pressure and a high vacuum, or a method of performing an esterification reaction of a dicarboxylic acid and a glycol and allowing the generated water to flow out, and then gradually reducing the pressure and performing a polycondensation under a high vacuum. Or, when a combination of dimethyl ester of dicarboxylic acid and dicarboxylic acid is used as a raw material, the transesterification reaction of dimethyl ester of dicarboxylic acid with glycol,
Further, there is a method in which a dicarboxylic acid is added to carry out an esterification reaction, followed by polycondensation under high vacuum. As the transesterification catalyst, manganese acetate, calcium acetate, zinc acetate and the like can be used, and as the polycondensation catalyst, known ones such as antimony trioxide, germanium oxide, dibutyltin oxide and titanium tetrabutoxide can be used. As a stabilizer, a phosphorus compound such as trimethyl phosphate or triphenyl phosphate, or a hindered phenol compound such as Irganox 1010 may be used. However, various conditions such as a polymerization method, a catalyst, and a stabilizer are not limited to the above examples.

Although the above polyester used in the present invention has water solubility, the term “water solubility” as referred to in the present invention is not strictly physicochemically, but includes those which dissolve and / or finely disperse in water.

Among such water-soluble polyesters, those having a glass transition temperature in the range of 35 to 80 ° C. are preferred. If the temperature is lower than 35 ° C., the handleability of the obtained composite yarn becomes poor, which is not preferable.
C. is not preferable because the solubility in water becomes insufficient. Within the above range, for example, it is easily soluble in hot water at a temperature of 50 ° C. or higher, but hardly soluble or less sticky in water at a temperature of less than 50 ° C., and the handleability is improved. The glass transition temperature was measured using a thermal analyzer (T
In AS100), the temperature is once raised to 180 ° C. at a rate of 10 ° C./min in a nitrogen stream, then cooled to −150 ° C., and then raised again for measurement.

The water-soluble polyester is preferably capable of being melt-spun. For example, it is desirable that the water-soluble polyester exhibits fluidity in the range of 180 to 300 ° C. and can be spun without foaming or decomposition.

Further, an antioxidant is added to the water-soluble polyester,
An additive such as a slipping agent may be blended.

Having described both the core and sheath components, the composite ratio of the core and sheath and the winding method will now be described. The polyurethane / water-soluble polyester composite ratio is preferably in the range of 1/2 to 50/1 in terms of the yarn cross-sectional area. This ratio is 1 /
If it is less than 2, the yarn is liable to be very brittle, and the handleability in the subsequent step becomes poor, and the amount to be dissolved increases, which is not preferable. Conversely, if the ratio exceeds 50/1, the spinnability tends to be poor, that is, the sheath component is easily broken, which is not preferable.

Further, the composite ratio needs to be changed depending on the application. That is, when the elongation at break is required to be 300% or less at the stage of the original yarn, such as a latent elastic yarn, the yarn cross-sectional area ratio is preferably in the range of 1/2 to 5/1. The winding method at this time is preferably a so-called spin draw method in which the film is drawn at a draw ratio of 1.5 to 5 times with or without heat during spinning. Final winding speed is 1,000 ~
A range of 3,500 m / min is preferred. That is, in this case, since the sheath component is easily oriented, the core component is also provisionally set, and the handleability as a yarn is greatly facilitated. If the ratio of the core / sheath component is less than 1/2, the fiber tends to be very brittle, and the handleability is poor in the subsequent steps such as stretching (for example, when the breaking elongation is about 8%, (The strength is extremely small, about 0.05 g / d.)
Further, the amount to be dissolved increases, which is not preferable. Conversely, if this ratio exceeds 6/1, the resulting composite yarn will have a large elongation at break and have elastic properties, resulting in poor handling properties, which is not good. As the breaking elongation of the obtained composite yarn,
It is preferably within a range of 300% or less, preferably 150% or less, and more preferably 100%. The strength is 0.5
g / d or more is also preferable from the viewpoint of operability.

Further, in the case of high-speed spinning for increasing the productivity during spinning of spandex, when the elongation is at least 500% at the stage of the original yarn, the above-mentioned core-sheath composite ratio is preferably 6/1 to 50/1. preferable. The winding speed at this time is 500-3,
A method of winding at a draw ratio of 1.4 m or less (the speed ratio of the first godet roller to the take-up roller) under the condition of no heat during spinning at 000 m / min is preferable. Usually, when spandex is produced at such a speed, the elongation is reduced and the stress becomes extremely high, whereas in the case of the present invention, since the sheath component is a water-soluble polyester, the orientation of the core component is hindered. it is conceivable that.

Next, any composite form may be used as long as the water-soluble polyester is exposed on the fiber surface. For example, various known shapes such as a core-sheath type and a cross shape shown in FIG. 1 can be used. Among these, it is preferable that the concentric composite form has the same center of gravity of both components of the core and the sheath in view of spinning stability, uniformity of the obtained yarn, and handleability of the yarn. On the other hand, a cross shape and the like are also preferable because an ultrafine yarn of polyurethane, which is difficult to produce by dry spinning or wet spinning, can be easily obtained. In this case, a yarn of 2 denier or less, for example, 0.2 denier per filament can be easily obtained. On the other hand, the cross-sectional shape of the composite yarn may be circular or irregular.

A method for producing a core-sheath type composite yarn having a crosslinked polyurethane as a core among the yarns of the present invention will be described. A melt composite comprising a part where a polyisocyanate is added and mixed to a part where a thermoplastic polyurethane is melt-extruded, a part where a water-soluble polyester as a sheath component is melt-extruded, and a spinning head having a known core-sheath type composite spinneret. It is preferable to carry out by a spinning device.

As a device used for adding the polyisocyanate during spinning, a known device can be used. It is also possible to use a kneading device having a rotating section in the portion where the polyisocyanate is added to and mixed with the polyurethane in a molten state, but it is more preferable to use a mixing device having a stationary kneading element. As the mixing device having the stationary kneading element, a known device can be used. The shape and number of static kneading elements vary depending on the conditions used, but should be selected so that the thermoplastic polyurethane and polyisocyanate are sufficiently mixed before flowing into the composite spinneret. Is essential, and usually 20 to 90 elements are provided.

The polymer thus mixed was used as a core component, and the water-soluble polyester as a sheath component was melted by another extruder. Then, both were guided to a core-sheath composite die and spun.
The composite yarn of the present invention can be obtained by winding by the above winding method.

When the yarn of the present invention is processed into staples or the like as it is or cut by continuous filaments, or is knitted, interwoven or mixed with other natural fibers or synthetic fibers to be processed into a web-like fiber structure. It does not require any special equipment and has very good workability. In particular, the composite elastic yarn of the present invention can be cut into staples and used as a blend with other fibers. Further, even in a tricot using urethane elastic yarn, there is no need to use a complicated warping machine dedicated to urethane elastic yarn, and a warping machine used for ordinary yarn such as nylon may be used. This was an extremely difficult field for elastic yarn. Furthermore, a heat-resistant polyurethane elastic yarn which is extremely fine (for example, 0.2 denier per filament) has not been hitherto found.

As a method of processing the yarn of the present invention, a method of forming the yarn of the present invention into a fabric such as a woven or knitted fabric or a nonwoven fabric, and then dissolving the sheath component with water in a scouring or dyeing step may be used.

[0041]

[Effects of the present invention] As described above, the yarn of the present invention is as follows:-The water-soluble polyester is easy to polymerize and has good hot melt stability. -The elongation of the obtained composite yarn can be freely adjusted.・ Because it is a melt spinning method, it is advantageous in industrial production.
Winding by high-speed spinning at 000 m / min is possible. Surprisingly, the polyurethane elastic yarn remaining after dissolution has a strength of, for example, 4 g / d and an elongation of 300% or more, which is a strong one that cannot be considered with ordinary urethane. -Ultrafine yarn of about 0.2 denier, which cannot be considered with conventional polyurethane elastic yarn, can be easily obtained. It has the feature of.

Since it has excellent characteristics as described above, it can be used for various applications. For example, if it is used for swimwear, a product having a shortened process and excellent operability can be suitably used for socks, innerwear, pantyhose and the like. Particularly in the case of ultrafine yarn, a product having unprecedented softness and texture can be obtained if used for such purposes.

[0043]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited thereto.

Example 1 Thermoplastic polyurethane Polytetramethylene glycol 35 having a molecular weight of 1,000
00 parts by weight, 1220 parts by weight of p, p'-diphenylmethane diisocyanate, and 1,4 bis (β-
It was synthesized by a conventional method using 245 parts by weight of (hydroxyethoxy) benzene. The relative viscosity of this polymer at a concentration of 1 g / 100 ml measured in dimethylformamide at 25 ° C. was 2.12.

Polyisocyanate 850 parts by weight of polytetramethylene glycol having a molecular weight of 850, p, p'-diphenylmethane diisocyanate 5
By reacting with 100 parts by weight, a viscous compound was obtained. The NCO wt% of this compound was 6.2 wt%.

Water-soluble polyester copolymer 38.74 parts by weight of dimethyl terephthalate, 31.95 parts by weight of dimethyl isophthalate, 10.34 parts by weight of dimethyl 5-sulfoisophthalate sodium salt, 54.48 parts by weight of ethylene glycol, Calcium acetate monohydrate 0.07
3 parts by weight, a transesterification reaction of 0.024 parts by weight of manganese acetate tetrahydrate under a nitrogen stream at 170 to 220 ° C. while distilling off methanol, and then 0.05 parts by weight of trimethyl phosphate, a polycondensation catalyst 0.04 parts by weight of antimony trioxide and 17.17 parts by weight of 1,4-cyclohexanedicarboxylic acid were added, and almost the theoretical amount of water was distilled off at a reaction temperature of 220 to 235 ° C. to carry out esterification. Thereafter, the pressure inside the reaction system was further reduced and the temperature was raised.
Polycondensation was performed at mmHg for 2 hours. Subsequently, polymerization was carried out in the same manner at a composition ratio shown in Table 1.

The obtained polymer was evaluated by the following method. Glass transition temperature: Thermal analyzer (TAS1) manufactured by Rigaku Corporation
00) at once at a rate of 10 ° C./min in a nitrogen stream.
The temperature was raised to 80 ° C., then cooled to −150 ° C., and the temperature was raised again for measurement. Water solubility: 425 g of water was added to 75 g of the polyester copolymer, and the mixture was stirred at 95 ° C. for 3 hours and evaluated.

Spinning of these polymers alone was performed.
The nozzle temperature was 230 ° C., the nozzle diameter was 0.5 mm, the winding speed was 500 m / min, the oil agent was a dimethyl silicone-based oil agent, and a brand 40 denier single filament yarn was collected. The results are shown in Table 1.

[0049]

[Table 1]

From Table 1, it was found that the polymer from Comparative Example 1-1 had poor handleability during drying, and that the yarn obtained therefrom had a large amount of sticking, so that the elongation was not measured. In Comparative Example 1-2, the content of dimethyl 5-sulfoisophthalic acid sodium salt was less than 5 mol%, and this polymer was insoluble in water. The yarn from Comparative Examples 1-3 was very brittle and poor in handleability. In Comparative Example 1-4, since the diol component was 100% diethylene glycol, the glass transition temperature was close to room temperature. In addition, spinning was not performed because drying was extremely difficult and handling was poor.

Next, an example in which a composite yarn is used will be described. The thermoplastic polyurethane was melted by an extruder, and the polyisocyanate was added in an amount of 15% by weight in the course of the melt, and then kneaded sufficiently with a 35-element static mixer (manufactured by Kenix). One water-soluble polyester was melted by another extruder, and these were separately weighed and led to a concentric 4-hole composite die (nozzle diameter: 0.5 mm). The first godet roller of the winder is 500 m /
Then, the second godet roller (draw roller) for drawing was changed to 2-3 times the speed of the first godet roller and wound up to obtain a yarn having a fineness of 40d / 2 filament. In addition, a 40 d / 1 filament polyurethane elastic yarn having no sheath component was spun alone (Comparative Example 1-6).
In the above spinning, an oil agent mainly composed of dimethyl silicon was used.

The results are shown in Table 2.

[0053]

[Table 2]

From Table 2, it is found that the composite ratio 2
In the case of / 1, it is understood that the elongation decreases and the strength increases when the temperature is applied or when the stretching ratio during spinning is increased. It can be seen that this elongation is about the same as ordinary nylon and polyester. Comparative Example 1-5 having a composite ratio of 15/1
In the case of, it is also understood that the elongation becomes large and the latent elastic yarn is insufficient. Furthermore, the yarns of the examples have long winding properties,
It was also excellent in unwinding and set-up.

Using the yarn of Example 1-5, the yarn was warped by a normal warping machine used in the production of a nylon tricot. 50 more
The yarn of the present invention shaped as d / 12f nylon as a front yarn was subjected to a knitting process as a back yarn. Further processing was performed, but there was no problem.

Example 2 Next, 1 mg / d of the yarns of Example 1-5 and Comparative Example 1-6 were used.
And treated in hot water of 100 ° C. for 30 minutes and air-dried. Table 3 shows the hot water shrinkage ratio (hereinafter abbreviated as heat collection) and physical properties after the hot water treatment. In addition, the sheath component of the yarn of Example 1-5 was completely dissolved after heat collection. The heat yield was determined by the following equation. Heat yield (%) = (Original length-Length after air drying) x 100 / Original length

[0057]

[Table 3]

From Table 3, it is quite surprising that the strength of the yarn of the present invention is much higher than the strength of a normal urethane elastic yarn of 1.4 g / d. Also, the so-called spontaneous shrinkage phenomenon in which the yarn of the example shrinks before the heat yield measurement was not observed. Further, the yarn of Example 1-5 was subjected to a stretching treatment at 150 ° C. under twice the conditions. The heat yield at this time showed a very high value of 70%.

Example 3 The water-soluble polyester used in Example 1 and the crosslinked polyurethane described in Example 1 were mixed (the composite ratio at this time was 1 /
2) Composite spinning into a cross shape as shown in FIG. At this time, the yarn was spun by the spin draw method (drawing ratio: 2.5 times) using the same apparatus as in Example 1 to obtain a yarn of brand name 40d / 20f. The results are shown in Table 4.

[0060]

[Table 4]

From Table 4, it can be seen that the elongation is small and not inferior to yarn such as nylon. Also, from this example, a 1.3 denier thin yarn per filament was easily obtained. The yarn was stretched 30% at room temperature, and then heat-treated in a 190 ° C. hot air dryer for 1 minute. Thereafter, the yarn was returned to room temperature and the yarn was relaxed, and the recoverability was calculated by the following equation. Recoverability (%) = (1.3 × original length−set length) ×
100 / (1.3 × original yarn-original length) As a result, the yarn is not melt-cut and the recovery is 2
It turned out to be 3%, indicating that there is sufficient heat resistance. This yarn was useful not only for clothing but also for medical purposes such as artificial blood vessels.

Example 4 In Examples 1 to 3, the composite ratio of the core / sheath was changed to 8/1, and the polyurethane side was arranged concentrically on the core and the water-soluble polyester side was arranged concentrically on the sheath. Stretching ratio at room temperature 1.
The spinning was performed in the same manner except that the winding speed was changed to a constant value of 05. For comparison, a polyurethane single yarn containing a polyisocyanate was similarly wound up. Brand is 40d / 1
It was a filament. The results are shown in Table 5.

[0063]

[Table 5]

As can be seen from the table, as the spinning speed increases, the strength increases and the elongation decreases. However, as compared with the single yarn of Comparative Example 4-2, a high spinning speed of 3,000 m / min is obtained. Surprisingly, the elongation and heat yield of each of the yarns are large and low, indicating that the yarn is very soft. or,
It can be seen that when the spinning speed is simply increased with a single yarn (Comparative Example 4-3), the yarn becomes very hard. On the other hand, the composite ratio is 1/6
In case (1), the strength was extremely low at 0.06 g / d, and thread breakage occurred.

[Brief description of the drawings]

FIG. 1 shows an example of a cross-sectional shape of a conjugate fiber suitable for the present invention.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yoshiaki Morishige 1418-3 Natajima, Yamaguchi, Yamaguchi Prefecture Examiner Masato Matsunawa

Claims (6)

(57) [Claims] 1. A composite fiber in which a polyurethane and a water-soluble polyester are bonded in a fiber cross-sectional area ratio (composite ratio) of 1/2 to 50/1 and the water-soluble polyester is exposed on a fiber surface; The water-soluble polyester has an aromatic dicarboxylic acid having a sulfonic acid salt as an acid component and / or an ester-forming derivative thereof (Component A) in an amount of 5 to 20 mol%, and an aromatic dicarboxylic acid excluding the component A and / or an ester thereof. 55% by mole or more of the derivative (component B), and an alicyclic dicarboxylic acid and / or an ester-forming derivative thereof (component C) and an aliphatic dicarboxylic acid and / or an ester-forming derivative thereof (component D); The component and the D component satisfy the relationship of 0 mol% ≦ C + 4 × D ≦ 40 mol%, and the glycol component is ethylene glycol 5
A composite elastic yarn comprising at least 0 mol%. 2. The composite elastic yarn according to claim 1, wherein the elongation at break is 300% or less when the composite ratio is 1/2 to 5/1. 3. The composite elastic yarn according to claim 1, wherein the elongation at break is 500% or more when the composite ratio is from 6/1 to 50/1. 4. The composite elastic yarn according to claim 1, wherein the water-soluble polyester has a glass transition temperature of 35 ° C. to 80 ° C. 5. An aromatic dicarboxylic acid having a sulfonic acid salt as an acid component and / or an ester-forming derivative thereof (A
Component), 5 to 20 mol% of the aromatic dicarboxylic acid and / or its ester-forming derivative (component B) excluding the component A, 55 mol% or more, and the alicyclic dicarboxylic acid and / or its ester-forming derivative ( C) and an aliphatic dicarboxylic acid and / or an ester-forming derivative thereof (D component), and the C component and the D component are 0 mol% ≦ C + 4.
XD ≦ 40 mol%, a water-soluble polyester composed of 50 mol% or more of ethylene glycol as a glycol component is bonded to polyurethane and the water-soluble polyester is exposed on the fiber surface. The fiber cross-sectional area ratio (composite ratio) of polyester is 1 /
Spinning speed of 1,000 to 3,500 m in the range of 2 to 5/1
A method for producing a composite elastic yarn, comprising winding at a rate of / min and a draw ratio of 1.5 to 5 times during spinning with or without heat. 6. An aromatic dicarboxylic acid having a sulfonic acid salt as an acid component and / or an ester-forming derivative thereof (A
Component), 5 to 20 mol% of the aromatic dicarboxylic acid and / or its ester-forming derivative (component B) excluding the component A, 55 mol% or more, and the alicyclic dicarboxylic acid and / or its ester-forming derivative ( C) and an aliphatic dicarboxylic acid and / or an ester-forming derivative thereof (D component), and the C component and the D component are 0 mol% ≦ C + 4.
XD ≦ 40 mol%, a water-soluble polyester composed of 50 mol% or more of ethylene glycol as a glycol component is bonded to polyurethane and the water-soluble polyester is exposed on the fiber surface. 6 / polyester fiber cross-sectional area ratio (composite ratio)
1-50 / 1, spinning speed 500-3,000m /
A method for producing a composite elastic yarn, comprising winding at a draw ratio of 1.4 or less under heat without heat in a minute.