JP2002088575A - Modified polyester fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a basic dye-dyeable polyester fiber that has good dyeability, excellent color fastness to light, high yarn strength, excellent resistance to alkali and high dimensional stability. SOLUTION: The polyester fiber is made from a polyester modified by copolymerizing an isophthalic acid component bearing a metal sulfonate group and a glycol component with a molecular weight of 400-6,000, a polymerization degree of 80-100, and the following physical properties: (A) elongation (E) at break: 25<=E<=40%; (B) peak contraction stress (F): F<=0.22 cN/dtex; (C) contraction stress peak temperature (T): T>=130 deg.C; (D) optical birefringence (Δn): 0.10<=Δn<=0.14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a modified polyester fiber which can be dyed with a basic dye. More specifically, the present invention relates to a modified polyester fiber having good dyeing properties and light fastness of dyed products, high yarn strength, excellent alkali resistance, and good dimensional stability.

[0002]

2. Description of the Related Art Conventionally, as a method for producing a dyeable polyester fiber of a basic dye, an isophthalic acid component containing a metal sulfonate group, for example, a 5-sodium isophthalic acid component is added and copolymerized before the polyester polycondensation reaction. A method is known (Japanese Patent Publication No. 34-10497).

However, in order to improve the dyeing property to a satisfactory level, a large amount of an isophthalic component containing a metal sulfonate group must be copolymerized. In order to suppress the thickening effect of the isophthalic acid component, the degree of polymerization of the polymer must be reduced. Must be lower. However, as a result, problems such as a decrease in yarn strength, a decrease in alkali resistance, and a decrease in light fastness have been caused, and the use of polyester fibers has been limited. Various methods have been proposed to solve this problem.

For example, in Japanese Patent Application Laid-Open No. 57-210014,
A method of copolymerizing a glycol component in an isophthalic acid component copolymerization system has been proposed. However, although these methods are effective in terms of alkali resistance and yarn strength, they still have serious problems in dimensional stability when woven into a fabric, and have insufficient dyeing properties. Generally, basic dye-dyed polyester fibers have a large internal strain in the fiber structure during the drawing process due to the copolymerization of bulky components, resulting in poor dimensional stability compared to ordinary polyester fibers. The basic dye-dyeable fiber obtained by the method had extremely poor dimensional stability after heat treatment.

Further, as a technique for improving dyeability, a method has been proposed in which a polymer having a prescribed copolymerization ratio of a metal sulfonate group-containing ester component is spun at a high speed of 5,000 m / min or more to improve mechanical properties and dyeability. However, the high-speed spinning method as described has problems such as insufficient alkali resistance.

[0006]

SUMMARY OF THE INVENTION The present invention overcomes the drawbacks of the prior art, and has good dyeing properties and light fastness of dyed products, high yarn strength, excellent alkali resistance, and good dimensional stability. It is an object of the present invention to provide a basic dyeable polyester fiber.

[0007]

In order to solve the above-mentioned problems, the present invention has the following arrangement.

A polyester fiber comprising a modified polyester obtained by copolymerizing an isophthalic acid component containing a metal sulfonate group and a glycol component having a molecular weight of 400 to 6000, and having a degree of polymerization of 80 to 100 and satisfying the following formula: Modified polyester fiber.

(A) Elongation (E) 25 ≦ E ≦ 40% (B) Peak shrinkage stress (F) F ≦ 0.22 cN / dtex (C) Shrinkage stress peak temperature (T) T ≧ 130 ° C. (D) Refraction (Δn) 0.10 ≦ Δn ≦ 0.14

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.

The polyester in the present invention refers to a polyester containing ethylene glycol as a main glycol component and terephthalic acid or an ester thereof as a main dicarboxylic acid component.

Part of the dicarboxylic acid component is a dicarboxylic acid such as isophthalic acid, diphenyldicarboxylic acid, naphthalenedicarboxylic acid, adipic acid, sebacic acid or dodecane diacid or an ester thereof, p-oxybenzoic acid, p-βoxy It may be replaced by an oxycarboxylic acid such as ethoxybenzoic acid or an ester thereof.

In order to produce a polyester from such a raw material, for example, dimethyl terephthalate, S component, ethylene glycol and a glycol component to be copolymerized are mixed and subjected to a transesterification reaction to obtain a glycol ester of terephthalic acid and S component and / or The low polymer is synthesized, and the product is subjected to a polymerization reaction by a conventional method to obtain the polyester of the present invention.

In synthesizing the polyester for carrying out the present invention, well-known catalysts, color inhibitors, ether bond by-product inhibitors, antioxidants, flame retardants and the like can be appropriately used.

In the present invention, the following can be achieved by copolymerizing the glycol component with the S component copolymerization system.

One of them was that a satisfactory dyeing property could be obtained by copolymerization of a glycol component with a small amount of copolymerized component. This is because the glycol component has a function of increasing the effective utilization ratio of the S component in the polymer to the basic dye.

Secondly, by copolymerization of a glycol component,
This is because a polymer having the same melt viscosity and a high degree of polymerization was obtained in the S-component copolymer. This is the glycol component
This is because the S-component copolymer has a function of lowering the melt viscosity of the polymer without lowering the degree of polymerization (thickening effect). Therefore, according to the present invention, by copolymerizing the glycol component in the S component copolymerization system, having a satisfactory dyeability in the range of melt viscosity that can be spun, especially at high speed, and a fiber having a polymerization degree of 80 to 100 is obtained. can get. This is obtained only when there is a decrease in the melt viscosity due to a decrease in the copolymerization amount of the S component due to the copolymerization of the glycol component, and a decrease in the melt viscosity due to the copolymerization of the glycol component.

In the present invention, the S component is a compound as shown in Chemical formula 1, and specifically, dimethyl (5-sodium sulfo) isophthalate, bis-2-hydroxyethyl (5-sodium sulfo) isophthalate, bis 4-hydroxybutyl (5-sodium sulfo) isophthalate and the like.

[0019]

Embedded image The S component is preferably copolymerized in an amount of 1.3 to 1.8 mol% with respect to the obtained polyester. If it is in this range, it will sufficiently react with the basic dye to obtain better dyeability, and
The thickening effect due to S component copolymerization is suppressed, and stable spinning can be performed without increasing the melt viscosity.

The S component may be added at any time as long as the polyester production reaction is completed.
It is preferable that the S component is sufficiently copolymerized in the polyester chain. Therefore, it is preferable to add at the stage before the initial stage of the polycondensation reaction.

The glycol component has a molecular weight of 400 to 600.
Those up to 0 are preferred. When the molecular weight is less than 400, the effect of improving the dyeability is small, and the glycol has a low boiling point, so that glycol is scattered out of the system during the polycondensation reaction, making it difficult to copolymerize a certain amount. On the other hand, a glycol component having a molecular weight exceeding 6000 deteriorates the oxidative degradation resistance of the copolymerized polymer, and the glycol component is difficult to copolymerize uniformly. The frosting property is reduced. The molecular weight of the glycol component is more preferably from 400 to 2,000.

A typical example of the glycol component having a molecular weight of 400 to 6000 is represented by the formula HO- (CH ₂ -CH ₂ -O) mRO- (CH ₂ -CH ₂ -O) n
-H (R is a divalent aliphatic hydrocarbon group having 3 to 20 carbon atoms, a divalent aromatic hydrocarbon group such as a phenyl group, a bisphenyl group, a naphthalene group, and m and n are the same or different integers In 1
≦ m + n ≦ 100. ), A bisphenol A-ethylene oxide adduct, a polyalkylene glycol represented by the following formula, and the like.

A (CnH2nO) mH (A is ClH2l + 1 or OH, l is 1
-10, n is 2-5, m is 3-100) Further, as the glycol component, polyalkylene glycol is more preferable. This is due to the fact that polyalkylene glycols are more advantageous than other glycols in obtaining a polymer having the required degree of polymerization to obtain fibers having a degree of polymerization of 80 to 100 because the viscosity reducing effect of polyalkylene glycol is larger than that of other glycols. As the polyalkylene glycol, polyethylene glycol having OH groups at both ends is more preferable. This is because the shorter the alkylene oxide unit and the more the glycol is copolymerized at random, the greater the effect of improving the dyeability and the effect of reducing the viscosity.

The copolymerization amount of the glycol component is preferably in the range of 0.5 to 1.9% by weight based on the obtained polyester. Within this range, a product having higher light fastness and oxidation-decomposition resistance and better dyeability can be obtained.

The glycol component can be added at any stage until the polyester production reaction is completed, but it is preferable to add the glycol component at a stage before the initial stage of the polycondensation reaction. During the addition, they may be added simultaneously with the S component, or may be added separately in any order.

The degree of polymerization of the modified polyester fiber obtained in the present invention must be 80 to 100. If the degree of polymerization is less than 80, the yarn strength of the polyester fiber aimed at the present invention is not at a level that satisfies, and if the degree of polymerization exceeds 100, the melt viscosity of the polymer having the degree of polymerization necessary to obtain the fiber is increased. It becomes too high and spinning becomes difficult.

As a method for obtaining a polymer having a degree of polymerization necessary for producing a polyester fiber having a degree of polymerization of 80 to 100, it may be obtained only by a polycondensation reaction, or may be used in combination with a solid phase polycondensation reaction. . In this case, if the polymer is melted during spinning, the degree of polymerization is reduced. Therefore, in order to obtain the polyester fiber of the present invention, it is necessary to use a polymer having a degree of polymerization of 85 to 105.

The basic dyeable polyester fiber of the present invention is required to be composed of a polyester having such a composition and satisfying the following physical properties of the yarn at the same time.

(A) Elongation (E) 25 ≦ E ≦ 40% (B) Peak shrinkage stress (F) F ≦ 0.22 cN / dtex (C) Shrinkage stress peak temperature (T) T ≧ 130 ° C. (D) Refraction (Δn) 0.10 ≦ Δn ≦ 0.14 The elongation (hereinafter referred to as E) of the filament constituting the basic dyeable polyester fiber of the present invention must be 25% or more and 40% or less. When E is less than 25%, single yarn breakage during weaving occurs frequently, resulting in poor weaving properties and a hard texture after weaving. Conversely, when E exceeds 40%, the dimensional stability of the woven fabric is poor, and the object of the present invention cannot be achieved.

Next, the birefringence (hereinafter referred to as Δn) needs to be 0.10 or more and 0.14 or less. When Δn is less than 0.10, the yarn strength and alkali resistance of the fiber are low and the object of the present invention cannot be achieved, and a satisfactory level of light fastness cannot be obtained. If Δn exceeds 0.14, the texture after weaving becomes hard, and a satisfactory level of dyeability cannot be obtained.

Next, the peak shrinkage stress and the shrinkage stress peak temperature (hereinafter referred to as F and T) greatly affect the properties after weaving. F needs to be 0.22cN / dtex or less and T needs to be 130 ° C or more. When F exceeds 0.22 cN / dtex, the dimensional stability is poor and the object of the present invention cannot be achieved. When T is less than 130 ° C., the texture of the obtained woven fabric becomes hard, and since there is no texture particularly after the alkali treatment, it is unsuitable for use in thin fabrics.

Next, one embodiment of the method for producing a basic dyeable polyester fiber of the present invention is shown in FIG. The basic dye-dyeable polyester fiber of the present invention is a polyester fiber having the above specific composition, which is melt-spun, cooled, and heated to a glass transition temperature ± 40 ° C. at a speed of 1500 m / min or more.
It can be obtained by a direct spinning drawing method in which the film is stretched between the heating take-up roller 3 and the heat drawing roller 4 heated to 100 ° C. or higher without being wound once, and then heat-treated with the heating drawing roller 4. It is preferable in terms of properties. In this case, in order to obtain the dimensional stability described above, it is preferable that the take-off speed is 1500 m / min or more. Pickup speed 1500m
/ min or more, the birefringence Δn is in the range of 0.10 to 0.14, good dyeability is obtained, and the peak shrinkage stress is 0.22 cN / dte
x or less and good dimensional stability after weaving can be obtained.

In the present invention, the term "fiber" refers to a long fiber and a fiber product such as a woven or knitted fabric containing the same. The fiber according to the present invention shows almost no decrease in mechanical properties and dyeability even after alkali reduction processing, and also has excellent dimensional stability. In this regard, the present invention has a remarkable effect which has not been considered before.

The fiber of the present invention has excellent dyeing properties not only as a single material, but also as a blended yarn, a mixed fiber, a processed yarn, and a mixed fabric with a yarn composed of different types of fibers. Demonstrate.

The use of the present invention is particularly suitable for sportswear, thin fabrics for women's clothing, and the like.

[0036]

Hereinafter, the present invention will be described in detail with reference to Examples.
These examples do not limit the scope of the present invention. In addition, each characteristic value in an Example was calculated | required by the following method.

(1) Degree of polymerization With respect to the obtained yarn, 0.5 g of a sample was dissolved in 10 ml of o-cresol, and after complete dissolution, cooled, 3 ml of chloroform was added, and a potentiometric titration was performed with a methanol solution of NaOH. The number of terminal groups per weight was determined, and the degree of polymerization was calculated by the following equation.

Degree of polymerization = [2 × 10 ⁶ ] / [Number of terminal groups (co / 10 ⁶ g) ×
Average molecular weight of polymer] (2) Shrinkage stress measurement Make a test length 10cm (actual loop length 20cm), hold the yarn in the measurement gripping part, heating rate 300 ° C / 120sec, initial load: 26cN / d
The temperature at which the shrinkage stress is the highest is T, and the stress at that time is F.

(3) Birefringence The retardation and optical path length of a single yarn were measured with a polarizing microscope, and the birefringence was calculated.

(4) Dyeability The knitted fabric obtained from the filament yarn to be evaluated was treated with malachite green (trade name, manufactured by Kanto Chemical Co., Ltd.) 5% owf, acetic acid 0.5 m
Dyeing is carried out for 60 minutes in a hot aqueous solution at 120 ° C. in a bath ratio of 1: 100 consisting of l / l and sodium acetate water 0.2 g / l. Next, the degree of dye immersion in the residual dyeing solution after lifting the tubular knitted fabric was measured, and the dye exhaustion rate of the tubular knitted fabric was determined. ○ and ○ are target levels of the present invention.

○: Exhaustion rate of 60 or more ：: Exhaustion rate of 50 or more, less than 60 ×: Exhaustion rate of less than 50 (5) Light fastness The tubular knitted fabric obtained from the filament yarn to be evaluated was Estr.
ol Blue N-3RL (trade name of Sumitomo Chemical) 1.5owf, acetic acid 0.5m
l / l, 0.15 g / l of sodium acetate, after dyeing for 60 minutes in an aqueous solution of 120 ° C. at a bath ratio of 1: 100, followed by hydrosulfite 2 g / l, NaOH 2 g / l, sandet according to a conventional method. G-900 2g /
The substrate is subjected to reduction washing in an aqueous solution of 80 ° C. for 20 minutes, washed with water and dried. The dyed tubular knitted fabric is subjected to photobleaching using a fade meter (Suga Test Machine) in accordance with JIS-L1044, and measured on a blue scale basis. Grade 4 or higher is the target level of the present invention.

(6) Alkali Resistance The yarn was treated in a 4% aqueous NaOH solution at a temperature of 95 ° C., and the yarn strength characteristics at a weight loss rate of 20% were determined. ○ is the target level of the present invention.

○: strength of 2.1 cN / dtex or more ：: strength of 1.8 cN / dtex or more and less than 2.1 cN / dtex ×: strength of less than 1.8 cN / dtex (7) Dimensional stability Basic dyeability Driving polyester yarn 92cm wide,
After weaving at a woven density of 31 yarns / cm and making it into a plain weave, heat treatment ((1) 100 ° C refining, (2) 135 ° C dyeing, (3) 160 ° C heat set)
Then, the shrinkage was measured. ○ is the target level of the present invention.

○: Shrinkage ratio of less than 7% ：: Shrinkage ratio of 7% or more and less than 8% X: Shrinkage ratio of 8% or more Examples 1 to 12, Comparative Examples 1 to 5 Dimethyl (5-sodium sulfo) to be added and copolymerized ) The polymer obtained by changing the amount of isophthalate and the added glycol compound as shown in Table 1 was melt-spun at a spinning temperature of 295 ° C., cooled, and then heated at 2500 m / min to a heating take-off roller heated to 90 ° C. After drawing, the film was stretched 2.0 times between the heating take-up roller and the heat drawing roller heated to 135 ° C. without being wound once, and heat-treated with the heating drawing roller to obtain a drawn yarn of 84 decitex 36 filaments. Table 1 shows the determination results of physical properties, dyeing properties, light fastness, alkali resistance and dimensional stability of this yarn.

Examples 1 to 12 satisfying the requirements of the present invention were all excellent in dyeability, light fastness, alkali resistance and dimensional stability.

On the other hand, in Comparative Examples 1 to 3 in which the molecular weight of the added glycol compound is out of the range of the present invention, the dyeability is poor and the effect of the present invention is not exhibited.

In Comparative Examples 4 and 5, where the degree of polymerization was out of the range of the present invention, the alkali resistance was at an unsatisfactory level.

[0048]

[Table 1] Examples 13 to 15 and Comparative Example 6 A modified polymer having the composition shown in Example 2 was melt-spun at a spinning temperature of 295 ° C, and after cooling, was taken up by a heating take-up roller heated to 90 ° C at 1000 to 3000 m / min. The film was stretched between a heating take-off roller and a heat stretching roller heated to 135 ° C. without being once wound, and heat-treated with the heating stretching roller to obtain a drawn yarn of 84 decitex 36 filaments. Table 2 shows the results of determination of the physical properties, dyeing properties, light fastness, alkali resistance, and dimensional stability of this yarn.

Examples 13 to 15 satisfying the requirements of the present invention were all excellent in dyeability, light fastness, alkali resistance and dimensional stability.

On the other hand, in Comparative Example 6, the peak shrinkage stress exceeded 0.22 cN / dtex, and the dimensional stability after weaving was extremely poor, so that the object of the present invention could not be achieved.

[0051]

[Table 2]

[0052]

According to the present invention, it is possible to provide a basic dye dyeable polyester fiber having good dyeing properties and light fastness of dyed products, high yarn strength, excellent alkali resistance, and good dimensional stability. .

[Brief description of the drawings]

FIG. 1 is a drawing showing a specific example of a manufacturing method of the present invention.

[Explanation of symbols]

 1: spinning pack 2: oil application device 3, 6: entanglement application device 4: heated take-up roller 5: heated draw roller 7: winder

Claims (3)

[Claims] 1. A polyester fiber comprising a modified polyester obtained by copolymerizing an isophthalic acid component containing a metal sulfonate group and a glycol component having a molecular weight of 400 to 6000, having a degree of polymerization of 80 to 100 and the following formula: Satisfied modified polyester fiber. (A) Elongation (E) 25 ≦ E ≦ 40% (B) Peak shrinkage stress (F) F ≦ 0.22cN / dtex (C) Shrinkage stress peak temperature (T) T ≧ 130 ° C (D) Birefringence (Δn ) 0.10 ≦ Δn ≦ 0.14 2. The modified polyester according to claim 1, wherein 1.3 to 1.8 mol% of an isophthalic acid component containing a metal sulfonate group and 0.5 to 1.9% by weight of a glycol component having a molecular weight of 400 to 6000 are copolymerized. fiber. 3. The modified polyester fiber according to claim 1, wherein the glycol component having a molecular weight of 400 to 6000 is a polyalkylene glycol represented by the following formula. A (C _n H _2n O) _m H (A is C _l H _{2l + 1} O or OH, l is 1 to 10, n is 2
~ 5, m is 3 ~ 100)