JPH026612A - Antistatic fiber - Google Patents

Abstract

PURPOSE:To obtain an antistatic fiber having practicality and commercial value by melt-spinning a polyester containing a polyoxyalkylene glycol under specific condition. CONSTITUTION:An antistatic polyester fiber having a charge leakage half life of <=150sec, preferably <=50sec is produced by the melt-spinning of a polyester containing >=0.5wt.% of a polyoxyalkylene glycol or its derivative through a spinneret provided with spinning nozzles for the production of solid fiber and having single nozzle area of >=0.2mm<2> under a condition satisfying the formula S>=0.02Q<2>+0.2 [S (mm<2>) is area of single nozzle; Q (g/min) is discharge rate per nozzle]. The obtained fiber has persistent antistaticity which is hardly changed after washing.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel antistatic fiber, and more specifically, the level of antistatic property and the persistence of antistatic property (durable antistatic property) are both conventionally known. This article relates to a new polyester-based synthetic fiber that is much superior to other synthetic fibers.

Synthetic fibers made from fiber-forming polyesters, such as polyethylene terephthalate, have excellent mechanical strength and durability, but on the other hand, these synthetic fibers have extremely high electrical resistance as a unique property. It has the fatal drawback of being easily charged with static electricity.

In order to prevent this tendency to be easily charged with static electricity, many various methods have been proposed. However, none of these methods has been able to satisfy all of the requirements at present in terms of cost increase, spinning operation stability, quality stability, antistatic performance and durability, balance with other fiber properties, etc. do not have. For example, in a method in which an antistatic agent is applied onto the surface of fibers, some or all of the antistatic agent disappears during washing, dyeing processes, etc., and durable antistatic performance cannot be obtained. In addition, in order to obtain fibers with durable antistatic properties, antistatic agents such as polyoxyalkylene glycols or their derivatives (hereinafter collectively referred to as POG) are added to the fiber-forming polyester prior to spinning. A method of making fibers by incorporating
However, when trying to obtain antistatic fiber by simply adding an antistatic agent such as POG to fiber-forming polyester before spinning and melt-spinning it by a conventional method, it is difficult to put it into practical use. In order to obtain fibers with sufficient antistatic performance, it is necessary to mix a large amount of POG.
OG impairs the inherent good mechanical properties of fibers made from fiber-forming thermal polyesters, and furthermore extremely impairs the light fastness of the resulting dyed fibers, and in this method no antistatic effect is obtained. Therefore, most of the commercial value of the fiber is lost.

The antistatic fiber manufacturing method that simply adds POG to fiber-forming polyester has the above-mentioned drawbacks, and in order to improve these drawbacks, a small amount of POG
Many methods for producing fibers with practical antistatic performance have been proposed.

Among them, there are methods such as adding a third component to POG, methods using static kneading elements, composite spinning methods, etc.
All of them have advantages and disadvantages, leading to increased silk reeling costs, increased raw material costs, unstable operations, unstable quality, etc., and are satisfied with all of these problems and have practical and commercial value. At present, it is not possible to obtain antistatic fibers.

The present inventors have solved the various problems mentioned above, and have achieved practical and
The present invention was developed as a result of extensive research aimed at obtaining antistatic fibers of commercial value.

That is, the present invention provides a spinneret having a spinning hole for producing solid fibers having a single opening area of 0.2 mm2 or more for polyester containing 0.5% by weight or more of polyoxyalkylene glycol or a derivative thereof. Using
(g/min) is a fiber formed by melt spinning under conditions that satisfy the following formula (1). )% and JIS-L-109
The polyester antistatic fiber is characterized by having a charge leakage half-life of 150 seconds or less according to the 4-A method.

The fibers of the present invention have significantly improved antistatic properties when compared with known antistatic fibers containing polyoxyalkylene glycol, and the improvements include the level of antistatic properties and It has durable antistatic properties, and even after washing, it has almost the same durable antistatic properties as before washing.
Moreover, its antistatic performance does not show any decline even after alkali reduction treatment. Antistatic level is POG
Although it varies depending on the content and spinning conditions, the charge leakage half-life (measurement method will be described later) is 150 seconds or less, 100 seconds or less if suitable spinning conditions are selected, and 50 seconds or less under especially suitable spinning conditions. .

Conventional fibers, on the other hand, have an extremely poor level of antistatic performance, and furthermore, the antistatic performance deteriorates significantly in both the 20-times washing process and the alkali weight reduction process described below.

The reason why the fiber of the present invention maintains excellent durable antistatic properties has not yet been precisely elucidated, but the special spinning conditions when producing the fiber of the present invention by the melt-spinning method, especially the single spinning hole. It is presumed that the fluidity of the POG-containing fiber-forming polyester within the pores greatly contributes to this. That is, by increasing the opening area of the single spinning hole to 3.2 m# or more and performing spinning under conditions where the flow friction loss energy of the fiber-forming polyester melt within the single spinning hole is extremely small, It is thought that POG, which is incompatible with the fiber-forming polyester, is formed into fibers in a dispersed state that is extremely effective for improving antistatic properties.

This can be inferred from the presence of numerous extremely long longitudinal grooves in the fiber axis direction that appear on the surface of the fibers through elution treatment, especially alkali treatment.

Figure 1 shows one embodiment of the present invention, in which a polyester containing 3% by weight of N POG was prepared using a spinneret having a circular spinning hole with an opening area of 0.785 mm per single hole. The polyester fiber obtained by spinning at a discharge rate of 0.5 g/min and drawing by a conventional method,
With an aqueous solution of sodium hydroxide at a concentration of 20 g/Jl, 90
A scanning electron micrograph at a magnification of 5,000 times showing the side surface of a fiber treated at a temperature of ~93°C and a weight loss of 21%. Figure 2 shows a polyester containing 3% by weight of POG.
Using a spinneret with a circular spinning hole with an opening area of 0.04 mm, the discharge amount per single hole was 0.5 g/
Conventional polyester fibers obtained by spinning under the conditions of 10 minutes and drawing in a conventional manner were treated with an aqueous solution of sodium hydroxide at a concentration of 20 g/min at a temperature of 90 to 93°C.
Scanning electron micrographs at 5000x magnification showing the side surfaces of the fibers shown in Figure 1. It is a continuous photograph, and the A end in (a) and the A end in (b) are continuous.

The countless multi-row grooves of the fiber of the present invention, which are developed on the fiber surface by alkali treatment, exhibit a novel morphology never seen before. These multi-stripe grooves are observed in side surface optical microscopic observation of conventionally known POG-containing fibers obtained by a method other than the fiber manufacturing method of the present invention but not subjected to alkali weight loss treatment. This is completely different from the apparently long streaks observed in the fibers, and POG exists inside the fibers uniformly arranged with a length and thickness suitable for charge leakage. This is something that only appears after alkali weight loss treatment. The fiber exhibiting this multi-row groove is obtained by a manufacturing method that satisfies the requirements shown in the manufacturing method of the fiber of the present invention described later. For example, the fiber surface of the fiber of the present invention after being treated with alkali is
As shown in Fig. 1, when viewed in a scanning electron micrograph at a magnification of a groove having substantially no end of the groove;

Further, as shown in FIG. 3, most of the multi-grooves developed by the alkali treatment of the fibers of the present invention extend continuously over a range of about 50 μm in length in the fiber axis direction. 1] of such narrow grooves is about 0.05 to 2μ. Also,
After the alkali treatment, the surface of the fiber of the present invention has approximately 5 fine grooves per 10μ of the planar distance in the outer circumferential direction of the cross section perpendicular to the fiber axis.
~50 exist. Furthermore, more than one-third of the multi-row grooves extend continuously in the fiber axis direction over a range of about 100 μm in length.

The length of the multi-row groove is estimated to be substantially 10 to 20 times or more the diameter of the fiber. On the other hand, when POG-containing polyester fibers were subjected to alkali weight loss treatment using the conventional method, the second
As shown in the figure, the fibers of the present invention do not exhibit the form of particularly long multi-row grooves arranged parallel to the fiber axis, but rather the form of very short streaks or spots with a length of several microns or less. Pores are seen, and these pores are completely different from the multi-row grooves that appear in the fibers of the present invention. In addition, in the case of polyester fibers that do not contain any POG, no multi-row grooves or pores appear on the fiber side surface even after alkali weight loss treatment. The grooves and pores are considered to be caused by POG. However, from a comparison between FIGS. 1 and 3 and FIG. 2, it can be seen that in the case of the fiber of the present invention, the alignment state of POG in the fiber direction is significantly different from that in the POG-containing polyester fiber produced by the conventional method. It can be clearly seen that they form a large group and are arranged in a continuous vertical manner.

The countless vertically long multi-row grooves arranged in the fiber axis direction as used in the present invention are developed by the alkali weight reduction treatment. An aqueous solution of an alkaline compound is used in such alkali weight reduction treatment. As the alkaline compound, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, etc. can be used, but the alkaline compound is not limited thereto. The weight loss rate of this treatment may be any value as long as it is 5 to 30% (by weight), but in the examples of the present invention, it is particularly about 20% (by weight). The conditions for weight loss treatment vary depending on the type of fiber, fineness, POG content, type of alkaline compound, etc., but for example, in the case of polyester, treatment with sodium hydroxide at 5-50°C for 10-100 minutes will reduce the weight to the specified level. The weight loss rate is obtained.

The fiber-forming polyester in the present invention may be any polyester that can be formed into fibers by melt spinning, and typical examples thereof include polyethylene terephthalate, polybutylene terephthalate, polyether ester, etc. However, it goes without saying that the invention is not limited to these examples.

In carrying out the present invention, among the above-mentioned fiber-forming polyesters, excellent effects are particularly exhibited on polyesters mainly composed of repeating units represented by the general formula (where n is an integer of 2 to 6).

It exhibits excellent effects on basic dye-dyeable polyester containing.

The polyoxyalkylene glycol or its derivative (POG) referred to in the present invention can be mixed into thermoplastic synthetic fibers to impart antistatic properties.
Specific examples include polyethylene glycol, polypropylene glycol, random or block combinations of ethylene oxide and propylene oxide, etc. Copolymers, polytetramethylene glycol, block copolymers obtained by adding ethylene oxide to polytetramethylene glycol, polyoxyalkylenes with hydroxyl groups at both ends such as neopentyl glycol, and compounds obtained by adding ethylene oxide to bisphenol glycols. Compounds such as monophenoxypolyethylene glycol, nonylphenoxypolyethylene glycol, sodium sulfophenoxypolyethylene glycol, diphenoxypolyethylene glycol, and compounds in which 2 moles of monophenoxypolyethylene glycol are bonded with 1 mole of tolylene diisocyanate, at one or both ends. Polyoxyalkylene compounds whose terminals are blocked via an ether bond, laurate of polyethylene glycol, phosphate of polyethylene glycol, or a partial alkali salt thereof, phosphonate of polyethylene glycol, or a partial alkali salt thereof, such as one or both terminals, are Esterified polyether compounds, block copolymers of polyethylene glycol and polyethylene terephthalate, block copolymers of polytetramethylene glycol and polyethylene terephthalate or polybutylene terephthalate, block copolymers of polyethylene glycol and polyε-capramide , polyethylene glycol with one or both ends cyanoethylated, polyethylene glycol with the cyano group converted into an amino group, and compounds obtained by adding ethylene oxide to a primary or secondary alkylamine. It goes without saying that the polyether compound referred to in the present invention is not limited to the above specific examples, and may be a single compound or a mixture of two or more of these compounds.

In addition, in the above POG, both ends are -〇■, C0
In the case of a group having active hydrogen such as 0H1-Nl2, the weight average molecular weight (hereinafter abbreviated as bimolecular weight) of the POG is preferably 6,000 or more. Further, when one end is blocked with a group having active hydrogen, the molecular weight of POG is preferably 4000 or more. Further, when both ends are blocked with a group having no active hydrogen, the molecular weight of POG is preferably 1000 or more.

The POG to be used in the present invention is the above-mentioned POG.
It is fine as long as it is OG. Furthermore, this additional P should be contained.
Antioxidants, ultraviolet absorbers, pigments, organic or inorganic ionic compounds, and other additives may be mixed in advance with OG.

When the amount of POG to be added is 0.5% by weight, the fiber surface after alkali weight reduction treatment cannot be clearly recognized as having countless vertically arranged multi-row grooves, and the antistatic performance is affected by half-life. 150
It exceeds seconds, which is insufficient for practical use.

Therefore, in the present invention, the amount of POG added to the fiber-forming polyester needs to be 0.5% by weight or more, more preferably 1.0% by weight or more. The upper limit of the POG content is not particularly limited in the present invention, but in general, as the POG content increases, the light fastness of the dyed fiber obtained deteriorates, so the light fastness of this dyed product is not suitable for practical use. It is necessary to appropriately select the upper limit of the POG content within a range that does not cause any problems.

According to the findings of the present inventors, there are differences depending on the type of POG, the type of POG, the molecular weight of POG, the presence or absence of a light resistance improver, etc.; If it exceeds 7% by weight, the light resistance will deteriorate significantly, so the upper limit for POG content is usually about 7% by weight. However, the antistatic property becomes better as the POG content increases.
Practically speaking, the POG content will be determined depending on the purpose and application from the viewpoint of both antistatic properties and light resistance.

When producing the fiber of the present invention, the method of adding PoG to the fiber-forming polyester is not limited as long as it is before spinning, and as long as it does not adversely affect the spinnability etc. It may be at any point from the initial stage of polymerization to the stage immediately before spinning.

The fiber of the present invention is produced by spinning a fiber-forming polyester containing 0.5% by weight or more of POG using a spinneret for producing solid fibers having a single spinning hole with an opening area of 0.2- or more. Melt spinning is carried out under conditions such that the relationship between the opening area S (mm) of a single hole in the spinneret and the discharge amount Q (g/min) per single hole satisfies the following formula (1), preferably the following formula 〇. The spun yarn is spun by a novel spinning method, and the spun yarn is cooled and solidified by a conventional method, then wound at a speed of 500 to 8,000 m/min, and stretched in a conventional manner. However, in the case of high-speed spinning of 6,000 m/min or higher, the orientation progresses sufficiently during the spinning process, so there is no particular need for stretching after winding.

S≧0. 02Q2 +0. 2 ・・・・・・・・・
...(1) S≧O, IQ2 +0. 2...
...... ■The fiber of the present invention can be used not only as a single material, but also in combination with different fibers other than the fiber of the present invention, such as blended yarn, blended yarn, processed yarn, and even different fibers or different fibers. It also exhibits excellent antistatic effects on mixed fibers with yarn, mixed knits, non-woven fabrics, heavy fabrics, multi-layered woven and knitted fabrics, etc.

The fibers of the present invention can be used for dress shirts, casual shirts, women's blouses, women's skirts, underwear, slacks, men's formal wear, resoice formal wear, knitwear, sportswear, coats, general outwear, baby wear, and children's wear. General clothing, men's suits,
Salmon 1. blouson, general uniform, special work wear, dust-free clothing, kimono, Japanese underwear, Japanese lining, household items (aprons, tablecloths, gloves, hats, etc.), bedding or sleepwear (futons, sheets, duvet covers) , pajamas, etc.), automobile interior ceiling materials and flooring materials, indoor rear goods, carpets, and other industrial materials, but of course the applications are not limited to these examples.

Examples of the present invention will be shown below. In the examples, unless otherwise specified, percentages are percentages by weight, and parts are parts by weight. In addition, the charge leakage half-life (hereinafter simply referred to as half-life), light resistance measurement method, and washing treatment in Examples were as follows.

(a) Half-life: After knitting the obtained filament, JIS-L-10
It was measured by method A (half-life measurement method) specified in 94-1980 (Electrostatic test method for woven and knitted fabrics).

(b) Light resistance: After knitting the obtained filaments, the knitted material was treated with 1.0% of Resolin Blue FBL (disperse dye manufactured by Bayer).
Dyeing with a dye solution with an owf 1 solubility ratio of 1:50 at 130°C for 60 minutes, reduction washing, and air drying.
L-0842-1971 (Test method for dye fastness to carbon arc lighting).

(c) Washing treatment: Wash the knitted fabric with a 0.5 g/l aqueous solution of neutral detergent at 40'C for 2 hours.
After washing with a home washing machine for 0 minutes and dehydrating,
After rinsing under running water at room temperature for 20 minutes and dehydrating again,
Dehydrate by rinsing with warm water at °C for 5 minutes. After repeating the above operation 20 times, it was air-dried and used as a sample for a chargeability test.

Example 1 Terephthalic acid and ethylene glycol were esterified by a conventional method, and after initial condensation, polyethylene glycol (average molecular weight 20.00
0), a hindered phenol-based antioxidant, 1,3.5-) Listyl 2.4.6-) Listyl (3,5-ditertiary-butyl-4-hydroxybenzyl)benzene (manufactured by Ciba Gaiki Co., Ltd., A mixture of 1.0% of Irganox (trade name: Irganox 1330) was added and melted and mixed so that the POG-containing bar 1 was 3% by weight.
Polymerization of G-containing polyester is completed, and the intrinsic viscosity is 0.635.
A POG-containing polyester (measured at 30°C in a mixed solvent of phenol/tetrachloroethane = 6/4) was obtained.

Using this polymer, the opening area S of a single spinning hole is 0.
．． Melt spinning was carried out at 290'C using a spinneret with 36 circular spinning holes for producing 785-sized solid fibers, with a discharge rate Q of 0.5 g/min per single hole, and the spun yarn was constantly 1300 m/min after cooling and solidifying with room temperature cooling air by method
The fibers thus obtained are taken up at a speed of
A double-sided circular knitted fabric of ♂ was knitted, and its half-life and light resistance were measured. Such measurements were carried out after washing the fibers 20 times before and after the alkali treatment. However, the light resistance was measured only before washing 20 times. The half-life and light resistance results are shown in Table 1.

The alkali weight loss treatment conditions in Example 1 are sodium hydroxide concentration 20g/I! , bath ratio 1:, 1001 temperature 90
At ~93°C, the alkali weight loss rate was 21% by weight.

Incidentally, electron micrographs of the side surface of the antistatic polyester fiber of the present invention obtained in Example 1 after the alkali weight loss treatment are shown in FIGS. 1 and 3.

Table 1 As is clear from Table 1, the antistatic polyester fiber of the present invention obtained in Example 1 has a short half-life of 20 to 28 seconds, and has a low level of antistatic property and a long duration of antistatic property. It can be seen that the properties are extremely good.

Furthermore, as shown in FIGS. 1 and 3, it can be seen that numerous grooves with a length of 100 μm or more are formed in the fiber axial direction on the fiber side surface after the alkali weight reduction treatment.

Comparative Example 1 Using the polyester containing 3% by weight of POG (intrinsic viscosity 0.635) obtained in Example 1, the opening area S of a single spinning hole was
Using a spinneret with 36 circular spinning holes for producing solid fibers with a diameter of 0.04 mm, the discharge amount Q per single hole was 0.5 g.
Melt spinning was carried out at 290° C./min, and the spun yarn was cooled and solidified with cooling air at room temperature, then taken off at a speed of 1300 m/min, and then stretched 3.5 times by a conventional method to obtain the obtained yarn. Fibers were knitted in the same manner as in Example 1, and their half-life and light resistance were measured in the same manner as in Example 1.

The alkali weight loss treatment conditions in Comparative Example 1 were the same as in Example 1. The results are shown in Table 2.

The side surface electron micrograph of the conventional POG-containing polyester fiber obtained in Comparative Example 1 after the alkali weight loss treatment is shown in the second image.
Shown in the figure.

The weight loss treatment conditions shown in FIG. 2 were the same as in Example 1. The results are shown in Table 3.

As is clear from Table 3 and Table 2, it can be seen that the POG-containing polyester fiber produced by the conventional method is significantly inferior in the level of antistatic property and the durability of the antistatic property as compared to the polyester fiber of the present invention. Furthermore, as shown in FIG. 2, the fiber side surface after the alkali weight loss treatment has a length of several μm, which is completely different from the polygonal grooves seen in the antistatic polyester fiber of the present invention shown in FIGS. 1 and 3. It can be seen that countless fine pores exist randomly.

Comparative Example 2 Fibers obtained in the same manner as in Comparative Example 1 except that the POG content was 7% by weight were knitted in the same manner as in Example 1, and the half-life and light resistance were the same as in Example 1. It was measured. Regarding Comparative Example 2, as is clear from Table 3 of Alkaline, the POG-containing polyester fiber made by the conventional method has an extremely inferior level of antistatic property compared to the polyester fiber of the present invention, and after 20 washes and alkaline treatment. It can be seen that the later half-lives show a marked decline.

Comparative Example 3 100 parts of dimethyl terephthalate, 6 parts of ethylene glycol
0 parts, calcium acetate monohydrate 0. 1 part of antimony trioxide and 0.04 part of antimony trioxide were charged into a transesterification tank, and the temperature was raised from 140°C to 230°C over a period of 4 hours in a nitrogen gas atmosphere, and the methanol produced was continuously removed from the system while esterification was carried out. An exchange reaction was performed. Subsequently, 0.05 part of trimethyl phosphate was added to the obtained product, which was then transferred to a polymerization vessel.

760w) Ig to l mm over 1 hour and 30 minutes
The pressure was reduced to Hg and the temperature was increased from 230'C to 280'C. Under reduced pressure of lmmHg or less, polymerization temperature 280℃
Polymerization was continued for an additional 2 hours at °C for a total of 3 hours and 30 minutes. After the reaction was completed, the polymer was discharged into water to obtain a rod-shaped polymer with a diameter of about 3 mm. Further, the polymer was cut into a length of about 5 mm to obtain polyester chips. [η] of the obtained polyester chip was 0.6t45. This chip is called polyester chip A.

On the other hand, 100 parts of dimethyl terephthalate, 60 parts of ethylene glycol, 0.1 part of calcium acetate monohydrate, and parts of antimony trioxide O,OS were charged into a transesterification tank, and heated from 140°C to 230°C over 4 hours under nitrogen gas atmosphere. The transesterification reaction was carried out while the methanol produced by raising the temperature to 'C was continuously distilled out of the system. The resulting product was then treated with polyethylene glycol 100 having a molecular weight of 1000.
Part 1, CIBA Ge1g3' antioxidant IRGAN
10,100.2 parts of OX and 0.2 parts of trimethyl phosphite.
After adding 0.05 parts, the mixture was transferred to a polymerization can.

Next, the pressure of the system was gradually reduced from 760 NG to IINIIIHg over 1 hour and 30 minutes, and at the same time, the pressure was reduced for 1 hour and 30 minutes.
The temperature was raised from 230°C to 280°C over 0 minutes.

Polymerization was carried out for an additional 2 hours at a polymerization temperature of 280'C under reduced pressure of 1 mm'Hg or less for a total of 3 hours and 30 minutes. After the reaction was completed, it was discharged into water and cut into approximately 5 mm length to obtain polyester chips. [η
] was C), 635. This chip is called polyester chip B.

Next, 95 parts of the polyester chip A dried under reduced pressure at 160°C for 5 hours and 5 parts of the polyester chip B dried under reduced pressure at 50°C for 24 hours were mixed, and the opening area of the single spinning hole was 0.04- Spinning temperature 295 using a spinneret of
Spinning at °C1 take-up speed of 900 rri/1 dea,
The yarn was then drawn at a draw ratio of 3.45 times and a pin temperature of 100'C to obtain a drawn yarn of 75 denier/36 filaments.

The fabric weight of the obtained fiber is 120 to 190 g/n? A double-sided circular knitted fabric was knitted, and the weight loss rate after alkali dissolution treatment was 0%, 10
%, and the half-life (seconds) of the knitted fabric at 25% before and after washing 20 times was measured.

The results are shown in Table 4.

4 is a series of 3000x scanning electron microscope photographs showing the side surface of the antistatic polyester fiber of the present invention obtained according to Table 1 after alkali weight loss treatment.

Claims (1)

[Scope of Claims] (1) Spinning polyester containing 0.5% by weight or more of polyoxyalkylene glycol or its derivatives for producing solid fibers in which the opening area of a single spinning hole is 0.2mm^2 or more Using a spinneret with holes, the opening area S (mm^2) of a single hole in the spinneret and the discharge amount per single hole Q (
g/min) is expressed by the following formula (1) S≧0.02Q^2+0
．． 2... Fibers formed by melt spinning under conditions satisfying (1), containing at least 0.5% (by weight) of polyoxyalkylene glycol or its derivatives, and complying with JIS-L-109.
A polyester antistatic fiber characterized by having a charge leakage half-life of 150 seconds or less according to the 4-A method. (2) The antistatic fiber according to claim 1, which has a charge leakage half-life of 100 seconds or less. (3) The antistatic fiber according to claim 1, which has a charge leakage half-life of 50 seconds or less.