JPH0598512A - Polyester fiber - Google Patents

Abstract

PURPOSE:To obtain the subject fiber, composed of a specific copolymerized polyethylene terephthalate, having specified properties, excellent in soft hand, strength and elongation characteristics and good in dyeability and light fastness. CONSTITUTION:The objective fiber is obtained by spinning polyethylene terephthalate copolymerized with a >=8C aliphatic dicarboxylic acid (preferably an 8-22C aliphatic dicarboxylic acid) in an amount of 2-22mol% (preferably 6-13mol%) based on the whole dicarboxylic acid. The fiber has >=4.0g/d strength, >=30% elongation and <=105 deg.C temperature at which the tandelta determined from dynamic viscoelastic measurement shows the peak.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyester fiber for clothing which has a soft texture, is excellent in strength and elongation characteristics, and has good dyeability.

[0002]

2. Description of the Related Art Polyester fibers, especially polyethylene terephthalate fibers, are widely used for clothing and industrial applications because of their excellent heat resistance, chemical resistance and mechanical properties. On the other hand, however, polyethylene terephthalate fibers have a hard feel as compared with other fibers, are prone to pilling, and are inferior in dyeability, so that they have disadvantages such as dyeing at high temperature and high pressure.

Recently, as a method for producing polyethylene terephthalate fibers, a one-step method in which the drawing step can be omitted, that is, a high-speed spinning method is being generalized from a conventional two-step method of manufacturing a spinning step and a subsequent drawing step. It is known that the fibers obtained by this high-speed spinning have a softer texture than the fibers obtained by the conventional two-step method and are suitable for clothing applications. Further, the dyeability is also improved as compared with the fiber produced by the conventional two-step method, but it is still not sufficient. For the purpose of improving dyeability, JP-A-57-161121 and JP-A-59-66514 disclose that a high-speed spun polyethylene terephthalate yarn is subjected to a high-temperature heat treatment to modify the fiber structure, thereby improving the dyeability. A method of imparting dyeability is disclosed. However, the easy dyeing property due to the modification is not yet sufficient, and it is not preferable from the viewpoint of manufacturing cost because a high temperature heat treatment process is added in the manufacturing process, and fluctuations in the processing temperature cause uneven dyeing property. Cause
Further, labor is required to strictly control the temperature in order to solve such a problem.

On the other hand, as a means for improving dyeability from a raw material polymer, JP-A-53-139821 discloses a method of copolymerizing polyoxyalkylene glycol, and JP-A-58-120815 discloses tetramethylene glycol. Method for copolymerizing glycol component such as 1,4-cyclohexanediol, and JP-A-59-19981
No. 4, discloses 1,4-cyclohexanedimethanol,
2,2-bis [4- (2-hydroethoxy) phenyl]
A method of copolymerizing propane is known. Although these methods can improve the dyeability, they have drawbacks such as a decrease in light resistance and a decrease in yarn strength.

[0005]

The object of the present invention is to modify polyethylene terephthalate to provide a softer texture than conventional polyester fibers,
An object of the present invention is to provide a polyester fiber for clothing, which has excellent strength / elongation properties, dyeability and light resistance.

[0006]

Means for Solving the Problems The above-mentioned objects of the present invention are as follows: strength 4.0 g / d or more, elongation 30% or more, and tan δ peak temperature determined by dynamic viscoelasticity measurement is 105 ° C. or less. Wherein the polyester fiber is polyethylene terephthalate in which 2 to 20 mol% of an aliphatic dicarboxylic acid component having 8 or more carbon atoms is copolymerized with respect to the total dicarboxylic acid component. Can be achieved.

The present invention will be described in detail below. Tensile properties of the polyester fiber of the present invention are required to have a strength of 4.0 g / d or more and an elongation of 30% or more. If it is not within this range, yarn breakage due to rubbing, impact, etc. in a high-order processing step such as weaving This is not preferable because problems such as the above occur and the process passability decreases. The elongation is more preferably 40% or more, and further preferably 45% or more.

The temperature at which tan δ has a peak, which is determined by dynamic viscoelasticity measurement, must be 105 ° C. or lower. Here, tan δ is obtained from dynamic viscoelasticity measurement at a heating rate of 3 ° C./min and a measurement frequency of 110 Hz. If it exceeds 105 ° C, the effect of improving the dyeability is small and dyeing at high temperature and high pressure is required, which is not preferable. For that reason, 100 ° C. or lower is more preferable.
However, it is not necessarily low, and if it is too low, the heat resistance of the fiber decreases, so from the practical viewpoint, it is preferably 60 ° C or higher, more preferably 65 ° C or higher, and 70 ° C or higher. The above is more preferable.

The polymer constituting the polyester fiber of the present invention is a copolymerized polyethylene terephthalate in which 2 to 20 mol% of all dicarboxylic acid components are composed of aliphatic dicarboxylic acid components having 8 or more carbon atoms.

An aliphatic dicarboxylic acid component is essential as a copolymerization component, and a copolymerization component containing a large amount of oxygen such as polyalkylene glycol or a copolymerization component having a large polarity such as 5-sodium isophthalic acid is used. ,Strength·
It is not preferable because it lowers the elongation property and the light resistance, for example, the color fastness. On the other hand, even an aliphatic dicarboxylic acid component having less than 8 carbon atoms is not preferable because the effect of the present invention cannot be obtained.

The aliphatic dicarboxylic acid component having 8 or more carbon atoms in the present invention is an aliphatic dicarboxylic acid component having carbon atoms constituting the carboxyl group between the two carboxyl groups and having 8 or more carbon atoms. Is. As specific examples, suberic acid (carbon number = 8), azelaic acid (carbon number = 9), sebacic acid (carbon number = 10), dodecanedioic acid (carbon number = 12), brassic acid (carbon number = 13), Eicosane diacid (carbon number = 20), dimer acid (carbon number = 3)
6)) and other aliphatic dicarboxylic acid components. It is preferable that the aliphatic dicarboxylic acid component has 8 to 36 carbon atoms, and it is more preferable that the aliphatic dicarboxylic acid component has 8 to 22 carbon atoms, because fibers having more excellent mechanical properties can be obtained. And has 8 to 16 carbon atoms
The aliphatic dicarboxylic acid component of is more preferable. The above-mentioned aliphatic dicarboxylic acid component may be used in combination of plural kinds of compounds.

The amount of the above-mentioned aliphatic dicarboxylic acid component is 2 to 20 mol%, preferably 6 to 13 mol% of the total dicarboxylic acid component constituting the polyester.
If it is less than 2 mol%, the effect of improving the dyeability is small, and it is 20
If it exceeds mol%, the heat resistance of the obtained fiber is lowered, which is not preferable. Further, within the range of 7 mol%,
Further, other dicarboxylic acids and / or diols can be contained within a range not exceeding the addition amount (molar fraction) of the aliphatic dicarboxylic acid. Further, various additives such as a matting agent, a flame retardant, an antioxidant, an ultraviolet absorber, an infrared absorber, a crystal nucleating agent, and a brightening agent are copolymerized or mixed as necessary. Is also good.

The polyester constituting the fiber of the present invention is
In the usual production process of polyethylene terephthalate, for example, at an arbitrary stage before the completion of the polycondensation reaction, the aliphatic dicarboxylic acid component having 8 or more carbon atoms is converted to dicarboxylic acid or a lower alkyl ester of dicarboxylic acid as described above. It can be produced by adding to the system and copolymerizing. At that time, the aliphatic dicarboxylic acid component having 8 or more carbon atoms may be added in the form of powder or after being dispersed, dissolved, or heat-treated in a suitable solvent such as ethylene glycol.

The polyester fiber of the present invention is 6000 m
The polyester can be obtained by melt-spinning the polyester by an ultra high-speed spinning method with a take-up speed of not less than / min.

In the spinning process, the atmospheric temperature below the spinneret surface is 150 ° C. within a range of 600 mm below the spinneret.
It is preferable from the viewpoint of spinnability that the spinning temperature is kept below the above spinning temperature. For example, a length of 50 mm or more and 600 mm or less, more preferably 200 m, which is heated at a temperature of 150 ° C. or more and a spinning temperature or less under a spin box in which a spinning pack is mounted.
This is achieved by using a heating cylinder having a length of m or more and 400 mm or less. In addition, as another method, the position of the spin pack mounted on the spin box is adjusted so that the length of the spinneret surface and the lower surface of the spin box is 50 mm or more and 600 mm or less, more preferably 200 mm or more and 400 mm or less. Also, the atmospheric temperature below the die surface can be set within the above-mentioned preferable range.

The fiber of the present invention is used for ordinary woven and knitting, strong twisting,
In clothing applications such as false twisting, it can be used as a fiber having characteristics such as softness and easy dyeability peculiar to ultra-high speed spun fiber while maintaining sufficient mechanical properties. Above all, it is possible to produce a polyester fiber suitable for raising applications. Also, as a spunbonded nonwoven fabric, it can be used as a nonwoven fabric having excellent properties not inferior to the conventional polyester spunbond.

The polyester fiber of the present invention is obtained by copolymerizing a relatively large amount of an aliphatic dicarboxylic acid component having a carbon number of 8 or more and having a high methylene group content, and is contained in an aromatic per unit volume of polyester more than that of ordinary polyethylene terephthalate. It is designed to have a low concentration of rings. Therefore, the flexibility of the molecular chain increases and the interaction between the polyester molecular chains becomes smaller, and the orientation of the molecular chain in the ultra-high speed spinning process is more advanced than that of polyethylene terephthalate in which the copolymerization component of the present invention is not copolymerized. Because it ’s hard
It is thought to be a fiber with a soft texture and good dyeability. And, although the copolymerization component of the present invention suppresses the molecular chain orientation in the ultra-high speed spinning process, it is considered that the fiber structure is not deteriorated because it forms the fiber structure without inhibiting the crystal formation.

Further, the fiber of the present invention uses, as a copolymerization component, an aliphatic dicarboxylic acid having an aliphatic chain having a small polarity, and a copolymerization component having a large polarity such as polyalkylene glycol and 5-sodium isophthalic acid is used. It is considered that the color fading fastness does not decrease, because moisture, oxygen, etc., which accelerate the deterioration reaction of the dye, are less likely to be present in the fiber than the used fiber, and thus become a substrate.

[0019]

The present invention will be described in detail below with reference to examples. Each characteristic value in the examples was determined according to the following method. (A) Intrinsic viscosity An orthochlorophenol solution was used and measured at 25 ° C. (B) Melting point Using a DSC-4 type manufactured by Perkin Elmer Co., Ltd., the melting point was determined at a temperature rising rate of 10 ° C./min. (C) Strength and Elongation of Fiber Using a Tensilon tensile tester manufactured by Orientec Co., Ltd., a load extension curve was measured at a sample length of 200 mm and a pulling speed of 200 mm / min. (D) Dynamic viscoelasticity Using Vibron DDV-II-EP manufactured by Orientec Co., Ltd., in the range of 30 to 200 ° C., the heating rate is 3 ° C. /
Min, tanδ curve is measured at a measurement frequency of 110 Hz
Peak value (tan δmax) and the peak temperature (Tmax
) Was asked. (E) Dyeability After knitting the fiber and scouring at 60 ° C. for 20 minutes,
After dyeing for 60 minutes under normal pressure and boiling conditions under the following conditions, 80
The product was reduced at 20 ° C. for 20 minutes and air dried. After heat setting at 150 ° C for 1 minute using a small pin tenter, 8
A stack of sample pieces was prepared. The L value was measured with a color difference meter (CR-200 manufactured by Minolta). The lower the L value, the deeper the color of the fiber. That is, a large amount of the dye is exhausted into the fiber, and the lower the L value, the better the dyeability.

Dyeing conditions Dye ND Super Auto BLUE S-GL 3% owf Dispersant Ionet TD-208 0.5 g / l pH adjuster PH500 0.5 g / l Lightfastness Cibatex LFN 2% owf Bath ratio 1:50 ( F) Fading fastness was dyed by the same method as in the above (E), and the prepared sample was irradiated with a fade meter at 83 ° C. for 300 hours to perform a light resistance test, and the grade was judged on a blue scale.

Examples 1 to 4 and Comparative Examples 1 and 2, 150 parts by weight of terephthalic acid, 20 parts by weight of sebacic acid (10 mol% based on total dicarboxylic acid), and 75 parts by weight of ethylene glycol were used as starting materials. To the low polymer obtained by the esterification reaction of 0.03 parts by weight of an 85% orthophosphoric acid aqueous solution as a coloring inhibitor, 0.06 parts by weight of antimony trioxide as a polycondensation catalyst, and cobalt acetate 4 as a toning agent. A polycondensation reaction was carried out by adding 0.06 part by weight of hydrate to obtain a copolyester. The melting point of this polymer,
Intrinsic viscosities are shown in Table 1 (Polymer D). This polymer was set at a spinning temperature of 280 ° C., a heating cylinder having a length of 100 mm and heated to 250 ° C. was mounted under the spin box, and a take-up speed of 60
Melt spinning at 00,7000 m / min, 75 denier / 3
A 6 filament polyester fiber was obtained. The strength, elongation, tan δmax, Tmax, dyeability, and color fastness of the obtained fiber are shown in Table 2 (Examples 1 and 2).

By the same polymerization method as above, the copolymerization ratio of sebacic acid was 3 mol% (polymer C in Table 1), 15 mol%
A copolymerized polyester of (Polymer E in Table 1) was obtained, the spinning temperature was (melting point +45) ° C., and melt spinning was performed at a take-up speed of 7,000 m / min by the same spinning method as described above to obtain 75 denier / 36 filaments. A polyester fiber was obtained. The characteristic values of the obtained fibers are also shown in Table 2.

As a comparative example, polyethylene terephthalate (polymer A in Table 1) obtained by the same polymerization method as described above except that no copolymerization was performed was used and the same spinning method was used. Table 3 shows the respective characteristic values of the polyester fiber obtained by melt spinning at a take-up speed of 6,000 and 7,000 m / min.
Also described in.

From the comparison between Examples 1 to 4 and Comparative Example 1 or 2, it can be seen that the polyester fibers within the scope of the present invention have a low L value and good dyeability. The color fastness was also good. Further, the fiber had excellent tensile properties of 4 g / d or more, and the texture was soft and good.

Examples 5 and 6, Comparative Examples 3 to 7 Copolymerized polyesters (polymers F, G, H, I and B in Table 1) were obtained in the same manner as above using various copolymerization components. It was Table 1 shows the intrinsic viscosity and the melting point of the obtained copolyester. Spinning temperature of these polymers (melting point +45)
℃, and take-off speed 7000m by the same spinning method as above
Melt-spinning was performed at a speed of 1 / min to obtain a polyester fiber having 75 denier / 36 filaments. However, in Comparative Example 6, polymer D was melt-spun and the take-up speed was 1500 m /
After being wound up once for 5 minutes, it was drawn 3.5 times at a drawing temperature of 60 ° C. to obtain a fiber. The characteristic values of the obtained fiber are also shown in Table 3.

Polyester fibers obtained from polymers F and G which are the copolyesters of the present invention (Examples 5 and 6)
Has a low L value, good dyeability, and good fastness to discoloration, but Polymer H (Comparative Example 3) containing no copolymerization component of the present invention has a small effect of improving dyeability, and Polymer I (Comparative Example). In the case of 4), although the dyeability is improved, the degree of fastness to discoloration is decreased and the strength is decreased, and therefore it is not suitable for practical use.

On the other hand, even with the copolymerized polyester of the present invention, the polymer B having a copolymerization ratio of less than 2 mol% (Comparative Example 5) does not show a dyeing property improving effect. Further, even if the copolymerization polyester of the present invention has a copolymerization ratio within the scope of the present invention, if the Tmax is high (Comparative Example 6), the dyeing property improving effect is small, which is not preferable.

[0028]

[Table 1]

[0029]

[Table 2]

[0030]

[Table 3]

[0031]

EFFECTS OF THE INVENTION The polyester fiber of the present invention has a soft texture, good dyeability, and good color fastness. Therefore, it can be provided as a polyester fiber suitable for a clothing product requiring fashionability.

Claims (1)

[Claims] 1. A strength of 4.0 g / d or more, an elongation of 30% or more,
And a polyester fiber having a tan δ peak temperature determined by dynamic viscoelasticity measurement of 105 ° C. or less, in which the aliphatic dicarboxylic acid component having 8 or more carbon atoms is 2 to all dicarboxylic acid components. Polyester terephthalate copolymerized with 20 mol% of polyester fiber.