JP3257838B2 - Antistatic polyester fiber 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 an antistatic polyester fiber and a method for producing the same. More specifically, the present invention relates to a highly economical high-speed spinning fiber that does not require a drawing step, has good spinnability, is flexible, and has excellent antistatic properties, and a method for producing the same. Things.

[0002]

2. Description of the Related Art Polyesters, particularly polyalkylene terephthalates such as polyethylene terephthalate and polybutylene terephthalate, and polyesters based on these, have been found to have various mechanical properties, durability and functional properties. Although it is remarkably superior to natural fibers, on the other hand, it has a drawback that various troubles are liable to occur at the time of spinning, processing, and use because static electricity is easily generated due to high volume electric resistance and surface resistance.

[0003] Various means have been proposed so far in order to prevent such disadvantages, but they have not yet been satisfied with all aspects of yarn production cost, antistatic property and its sustainability, and fiber performance. Is the current situation. The simplest means is to apply an antistatic agent to the fiber surface,
In this case, there is a disadvantage that the antistatic agent is easily lost in the dyeing process or washing, and a permanent antistatic effect cannot be expected.

[0004] Permanence of the antistatic effect is a fundamental required characteristic of the antistatic fiber, and from this viewpoint, a method of modifying the polyester itself by kneading an antistatic agent into the polymer can be said to be preferable. . Regarding this, there is known a method of uniformly mixing a polyoxyalkylene glycol into fibers as disclosed in JP-B-39-5214. However, this method requires a large amount of polyoxyalkylene glycol as much as 10% by weight to exhibit sufficient antistatic properties, and the resulting antistatic polyester fiber has greatly reduced mechanical properties and light resistance, and cannot be used. Will not be.

Various means for overcoming this drawback have been proposed. For example, as disclosed in Japanese Patent Publication No. 47-11280, a method of mixing and mixing polyoxyalkylene glycol and sodium alkylbenzene sulfonate. As disclosed in JP-A-53-149246, there is known a method in which polyoxyalkylene glycol and sodium alkylsulfonate are used in combination and mixed. By these methods, the amount of polyoxyalkylene glycol used can be reduced, and an antistatic polyester fiber with little deterioration in physical properties can be obtained.

However, in the method disclosed in Japanese Patent Publication No. 47-11280, although the packing pressure does not increase at the time of spinning and the spinning properties are good, after the dyeing in the processing step and the washing after the product is finished, However, there is a problem that the anti-static performance durability is poor. In the method of JP-A-53-149246, the durability of the antistatic performance is improved, but the coloring of the fibers is remarkable, and the rise of the pot pressure is fast, so that the exchange cycle of the spinning nozzle is short. However, there are drawbacks such as a decrease in productivity and an inferior yarn-making property.

As described above, a large number of antistatic methods such as a coating method, a kneading method, and a multi-spinning method have been proposed, but a practical level of antistatic effect, its permanence, mechanical properties, and light resistance. At the present time, there has not yet been obtained a material which simultaneously satisfies various factors such as yarn production cost. Furthermore, in a high-speed spinning process that does not require a drawing step, it is common to perform stricter polymer filtration than in a normal spinning method, so that an antistatic property that satisfies a pressure increase and a spinning property in the spinning step. Polyester fibers have not yet been obtained.

The present invention solves the problems of the conventionally known antistatic polyester fiber, has excellent antistatic properties, has little deterioration in physical properties, and has a complicated spinning technique even when spun by a high-speed spinning method. It is an object of the present invention to provide an antistatic polyester fiber having good spinning properties without using the same and a method for producing the same.

[0009]

The present inventors have conducted intensive studies and have found that the use of a polyester composition having a specific composition provides a flexible and good antistatic property without impairing the excellent properties inherent in polyester fibers. The inventors have found that an antistatic polyester fiber having an effect can be stably produced industrially, and arrived at the present invention. That is, the antistatic polyester fiber according to the present invention has (a) a weight average molecular weight of 40 per 100 parts by weight of the acid component constituting the polyester.
00 to 50,000 polyethylene glycol,
A polyester fiber obtained by blending (b) an alkali metal salt of an alkyl sulfonic acid and (c) an alkali metal salt of an alkylbenzene sulfonic acid so as to satisfy the following formulas (1) to (3). (Tmax) at which the mechanical loss tangent (tan δ) at the maximum is
And the maximum value of (tan δ) [(tan δ) max] is (4)
It is characterized by being within the range shown by the formula and the formula (5). 0.5 ≦ a ≦ 5 (1) 1.5 ≦ b + c ≦ 5 (2) 0.05 ≦ b ≦ 1.0 (3) 0.12 ≦ (tan δ) max ≦ 0.20 (4) 90 ° C. ≤ (Tmax) ≤ 120 ° C (5)

The method for producing an antistatic polyester fiber according to the present invention comprises: (a) a weight average molecular weight of 4,000 to 50,000 per 100 parts by weight of an acid component constituting the polyester.
The winding speed of a polyester obtained by blending polyethylene glycol of the formula (1), (b) an alkali metal salt of an alkylsulfonic acid, and (c) an alkali metal salt of an alkylbenzenesulfonic acid so as to satisfy the following formulas (1) to (3): 5200
It is characterized by spinning at m / min or more. 0.5 ≦ a ≦ 5 (1) 1.5 ≦ b + c ≦ 5 (2) 0.05 ≦ b ≦ 1.0 (3)

Hereinafter, the present invention will be described specifically. The polyester serving as the base of the polyester fiber of the present invention is a polyester having an ethylene terephthalate unit as a main repeating unit, and as a dicarboxylic acid component other than the terephthalic acid component, for example, isophthalic acid, adipic acid, sebacic acid, naphthalenedicarboxylic acid, or the like. An acid component may be used, or 1.4-butanediol, 1.6-hexanediol, neopentyl glycol, 1.4-cyclohexanedimethanol, or the like may be copolymerized as a glycol other than the ethylene glycol component. Of these,
Polyethylene terephthalate is preferred.

The weight average molecular weight of the polyethylene glycol used in the present invention is in the range of 4,000 to 50,000, preferably in the range of 10,000 to 30,000. If the weight average molecular weight is less than 4000, the obtained fiber has poor antistatic properties at a friction band voltage of 2,000 V or more, and has insufficient durability by washing treatment. On the other hand, when the weight average molecular weight exceeds 50,000, the fibers are colored, and the yarn breakage at the time of spinning is increased, and the spinning property is deteriorated. The amount of the polyethylene glycol compounded is the acid component 10 constituting the polyester.
It is 0.5 to 5.0 parts by weight relative to 0 parts by weight, and more preferably 2.0 to 4.0 parts by weight. Fibers having a sufficient antistatic effect cannot be obtained from a polyester composition containing less than 0.5 parts by weight of polyethylene glycol, and fibers made from a polyester composition exceeding 5.0 parts by weight are lightfast. In addition, the mechanical properties are deteriorated, and coloring is remarkable.

The alkali metal salt of alkylsulfonic acid and the alkali metal salt of alkylbenzenesulfonic acid used in the present invention are represented by the following general formula. Alkali metal salts of alkyl sulfonic acid alkali metal salt of R-SO ₃ M alkylbenzenesulfonate:

Embedded image [R and R 'are alkyl groups having 8 to 20 carbon atoms, M and M' are Li, Na, K]

The total amount of the alkali metal salt of alkyl sulfonic acid and the alkali metal salt of alkyl benzene sulfonic acid is 1.5 to 5.0 parts by weight, more preferably 2.0 to 3.0 parts by weight. A fiber having a sufficient antistatic effect cannot be obtained from a polyester composition in which the total amount of the alkali metal salt of alkylsulfonic acid and the alkali metal salt of alkylbenzenesulfonic acid is less than 1.5 parts by weight,
On the other hand, if the content exceeds 5.0 parts by weight, the fiber becomes a markedly colored fiber, and the spinnability is remarkably deteriorated.

Of the above alkali metal salts, it is important to mix a certain amount of the alkali metal salt of alkylsulfonic acid, and the amount is 0.05 to 1.0 part by weight, and more preferably 0.1 to 1.0 part by weight. It is 3 to 0.7 parts by weight. If the amount of the alkali metal salt of the alkyl sulfonic acid is less than 0.05 part by weight, a fiber having a sufficient antistatic effect can be obtained even if the amount of the alkali metal salt is adjusted to satisfy the expression (2). On the other hand, if the content exceeds 1.0 part by weight, the fibers become remarkably colored fibers, and the pot pressure rises remarkably, thereby deteriorating the spinnability.

Although it is not clear yet why the compounding of the alkali metal salt of alkyl sulfonic acid and the alkali metal salt of alkyl benzene sulfonic acid within a certain specific range results in excellent spinning properties and excellent antistatic performance. Alkali metal salt of alkylsulfonic acid is more emulsified and dispersed by alkali metal salt of sulfonic acid to increase compatibility with polyethylene terephthalate, and can avoid problems in the spinning process such as increase in pack pressure and decrease in spinnability. it is conceivable that.

The antistatic polyester fiber produced by the high-speed spinning method, which has no problem of pot pressure rise, has good spinning properties and is excellent in antistatic properties, is provided by the present invention for the first time.

The polyethylene glycol, the alkali metal salt of alkyl sulfonic acid and the alkali metal salt of alkyl benzene sulfonic acid used in the present invention can be compounded by any method. It can be blended with polyester. That is,
Any stage until the molding of the polyester is completed, for example, before the start of the polycondensation reaction of the polyester, during the polycondensation reaction,
At the end of the polycondensation reaction. Alternatively, an ordinary polyester resin may be manufactured, and the pellets and the additives used in the present invention may be mixed by an extruder. Among these, it is most preferable from the viewpoint of dispersibility that these additives are simultaneously added before starting the polycondensation reaction or during the polycondensation reaction when producing the raw material polyester resin.

The polymer obtained by polycondensation according to this known method can be produced by a well-known melt spinning method. Among them, the high-speed spinning method which does not require a drawing step improves the productivity and improves the drawing step. This is a preferable method because the omission can bring about cost reduction and an effect of improving dyeability can be expected, so that cross-knitting and weaving with other types of fibers can be facilitated and applications can be expanded. A winding speed of 5200 m / min or more is necessary to obtain a highly oriented yarn having sufficient practical properties only by a melt spinning step without going through a stretching step.
Yarn obtained at a winding speed of 0 m / min or less elongates in the weaving and knitting steps, and frequently causes dyeing spots and quality deterioration of the fabric, which is a practical obstacle. Since the yarn obtained by the present invention has a softer feeling than the yarn obtained by the drawing method, it is particularly useful in the inner fields such as foundation and lingerie.

The characteristic of the antistatic polyester fiber of the present invention obtained by the above-mentioned production method is that the temperature (Tmax) at which the mechanical loss tangent (tan δ) at the measurement frequency of 110 Hz is maximum.
And the maximum value of (tanδ) [(tanδ) max] lies in the range represented by the equations (4) and (5). 0.12 ≦ (tanδ) max ≦ 0.20 (4) 90 ° C. ≦ (Tmax) ≦ 120 ° C (5) When (tanδ) max is larger than 0.20, and (Tma
If x) is lower than 90 ° C, the antistatic performance at the yarn stage is good, but the antistatic agent is likely to fall off due to the high-temperature dyeing treatment in the processing process and repeated washing after the product is manufactured. The antistatic performance is greatly reduced, and the friction band voltage greatly exceeds 2,000 V. When (tan δ) max is smaller than 0.12 and (Tmax) is larger than 120 ° C., the antistatic performance level at the yarn stage becomes 2000 V in friction band voltage.
Above is low. The present inventors have clarified for the first time that the present inventors have extremely good antistatic performance and antistatic durability only when (tan δ) max and (Tmax) satisfy the above formulas (4) and (5). Was.

Although the reason for this is not clear yet, it is presumed that the difference in the microstructure of the fiber caused a difference in the bleeding behavior of the antistatic additive on the fiber surface. The antistatic polyester fiber of the present invention may contain an antioxidant such as a hindered phenol compound or a phosphite compound. In addition, a coloring agent, a matting agent, and other additives may be added as needed.

[0022]

Hereinafter, the present invention will be described in detail with reference to Examples.
These examples do not limit the scope of the present invention. The measured values in the examples are measured by the following method. (1) Reduced viscosity of polymer; measured at 35 ° C. using 0-chlorophenol as a solvent. (2) Friction band voltage; (i) Apparatus and material: Rotary drum type friction band voltage measuring apparatus (Kyoto University Chemical Research Type rotary static tester)
[Koa Shokai] Oscilloscope Friction cloth: cotton [Kanakin No. 3] Refined and bleached, glue-free product (ii) Adjustment of test piece: Friction cloth: 2.5 cm x 16 cm Test cloth: 3.8 cm x 8 cm Knitted fabric 3 each Collect one sheet. <Original sample> A one-piece knitted fabric knitted using the obtained yarn was scoured at 60 ° C. for 30 minutes in a nonionic scouring agent 2 g / l bath and dried. <After washing> The above-mentioned scoured cloth was dried and set at 160 ° C. for 30 seconds and then subjected to the following dyeing and washing treatments. Dyeing: Resoline Blue.FBL 1% owf (Disperse dye manufactured by Bayer) 130 ° C × 60 minutes Washing: Detergent “Zab” (Kao Corporation product) 2 g / l 40 ° C. × 5 minutes Washing is repeated 30 times Room temperature × 2 minutes Rinsing is repeated 30 times. (Iii) Test operation Humidity control: Leave in an atmosphere of 20 ° C. ± 2 ° C., 40% ± 2% RH all day and night. Atmosphere of measurement chamber: 20 ° C ± 2 ° C, 40% ± 2% RH Sample: Number of layers: 1 Drum rotation speed: 400 rpm Equilibrium time: 1 minute Contact pressure load: 500 g (iv) Operation, experiment: 1 test cloth Attach it to the rotary drum of the rotary static with the sheet face up, and attach one friction cloth in parallel to the clips at both lower ends at the position where it contacts the test cloth.
Apply a load of 00g. The recorder was operated in the order of a rotating drum and an oscilloscope, and when the charging equilibrium time was reached, a friction band voltage (V) was read and represented by an average value of three sheets. As for the relationship between the antistatic effect and the frictional band voltage, the latter is about 2,000
If the voltage is 0 V (preferably 1,000 V) or less, an antistatic effect is exhibited. (3) Dynamic loss tangent (tan δ) manufactured by Toyo Baldwin Co., Ltd., Leo Vibron (RheoV
iblon) Using a DDVII-EA type dynamic viscoelasticity measuring device, tan δ at each temperature is measured in dry air at a measurement frequency of 110 Hz and a heating rate of 5 ° C./min using a sample of about 0.25 g. From the tan δ-temperature curve, the tan δ peak temperature (Tmax)
The same peak height [(tan δ) max] as [° C.] is obtained.

Examples 1 to 3 and Comparative Examples 1 to 11 700 kg of dimethyl terephthalate and 470 kg of ethylene glycol were stirred for 2 hours and 30 minutes from 140 ° C. to 230 ° C. in a nitrogen stream using 0.7 kg of calcium acetate as a catalyst. The temperature was raised to terminate the transesterification reaction. Then, 0.53 kg of trimethyl phosphate, 1.8 kg of an ethylene glycol slurry containing 20% by weight of titanium dioxide, 0.35 kg of antimony (II) trioxide, and the blending amounts of the various additives shown in Table 1 shown in Table 1. After the addition, the temperature was raised from 240 ° C. to 260 ° C. over 1 hour, and then reduced to 1 mmHg or less while the temperature was raised from 260 ° C. to 280 ° C. over 1 hour. In this state, a polycondensation reaction was performed for 2 hours to obtain a polymer having a reduced viscosity of 0.72. Next, the obtained polymer was dried by a conventional method, and was passed through a filter having a size of 20 μm at a spinning temperature of 290 ° C. at a spinning temperature of 290 ° C., a slit width of 0.11 mm, a slit length of 0.34 mm, and a number of holes using an apparatus shown in FIG. After spinning, cooling and solidifying from a No. 12 triaxial isometric spinneret, a finishing agent was applied and wound at each winding speed shown in Table 1 to obtain a 30d / 12f fiber.

Tables 1 and 2 show the conditions during spinning and various physical properties of the obtained fiber. As can be seen from this table, even when the molecular weight and blending amount of polyethylene glycol are satisfied, the amount and ratio of sodium alkylsulfonate and sodium alkylbenzenesulfonate do not satisfy the method of the present invention (Comparative Examples 5, 6, 7). And 8) have a problem that coloring of fibers occurs or frictional voltage after washing is poor. Also, as can be seen from Comparative Examples 9, 10, and 11, even when the polymer composition of the present invention is satisfied, the maximum values of the temperature (Tmax) and (tan δ) at which the mechanical loss tangent (tan δ) shows the maximum [(tan δ) ma
If x] is not obtained, the yarn or the frictional voltage after washing is poor, and excellent antistatic performance cannot be obtained. On the other hand, it is understood that the polyester fiber of the present invention has no coloring of the fiber, has excellent antistatic performance, and has a good spinning state.

[0025]

[Table 1]

[0026]

[Table 2]

[0027]

The polyester fiber obtained by the present invention has excellent processability, antistatic performance and a soft feeling without impairing the original excellent properties, and is an antistatic polyester fiber with little coloring. It is. In addition, the production method of the present invention is capable of industrially producing such fibers without an increase in pot pressure or yarn breakage.

[Brief description of the drawings]

FIG. 1 is a schematic view of an apparatus used in an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Yarn 2 ... Spinning head 3 ... Tubular heating cylinder 4 ... Oil dispensing device 5 ... Converging guide 6 ... Fluid entanglement processing device 7 ... Take-up roll

──────────────────────────────────────────────────の Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) D01F 6/92 301-309 D01F 6/86 301-307

Claims (2)

(57) [Claims] 1. A weight-average molecular weight of 4,000 to 50 (a) per 100 parts by weight of an acid component constituting a polyester.
And (c) an alkali metal salt of an alkylbenzene sulfonic acid, and (c) an alkali metal salt of an alkylbenzene sulfonic acid so as to satisfy the following formulas (1) to (3). And the mechanical loss tangent (tan
δ) has the maximum temperature (Tmax) and the maximum value of (tanδ) [(tanδ) max] in the range shown by the formulas (4) and (5), and is excellent in washing durability. A polyester fiber having properties. 0.5 ≦ a ≦ 5 (1) 1.5 ≦ b + c ≦ 5 (2) 0.05 ≦ b ≦ 1.0 (3) 0.12 ≦ (tanδ) max ≦ 0.20 (4) 90 ° C. ≦ (Tmax) ≦ 120 ° C. (5) 2. A weight-average molecular weight of 4,000 to 50 (a) per 100 parts by weight of an acid component constituting the polyester.
A polyester obtained by blending polyethylene glycol, (b) an alkali metal salt of an alkylsulfonic acid, and (c) an alkali metal salt of an alkylbenzenesulfonic acid so as to satisfy the following formulas (1) to (3): A method for producing an antistatic polyester fiber having excellent washing durability by spinning at a take-up speed of 5200 m / min or more. 0.5 ≦ a ≦ 5 (1) 1.5 ≦ b + c ≦ 5 (2) 0.05 ≦ b ≦ 1.0 (3)