JPH1150350A - Wiping cloth having durable removal of electricity - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a wiping cloth excellent in cleaning power, dust resistance, washing durability and design, useful in the field of medicine industries, electronic precision industries, etc., by mixing a specific fabric with a fixed amount of prescribed electroconductive fibers. SOLUTION: This wiping cloth is obtained by mixing a fabric consisting essentially of an extrafine yarn having a single yarn fineness of 0.01-0.8 denier and a section of two or more angles with 20-120 degrees with <=3 wt.% of an electroconductive fibers having a three layer structure comprising a polyamide layer having <=9×10<8> Ω/cm.f electrical resistance at 1 kv application as an innermost layer, a polymer layer containing >=10 wt.% inorganic fine particles as an intermediate layer and an outermost layer composed of a fiber- forming polymer and <=7.0 μC/m<2> electric charge density after washing 250 times. Preferably the ratio of a hydrophilic yarn such as a polyamide yarn having 0.01-0.8 denier mixed in the fabric is 10-60 wt.%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wiping cloth having excellent dust-removing properties, and more particularly to a wiping cloth which can be used in a field where dust and dirt are not required to be adhered to. Does not drop even after
The present invention relates to a wiping cloth having a very high so-called dust removing effect.

[0002]

2. Description of the Related Art Many wiping cloths are made of cellulose fibers or the like. However, such wiping cloths are inferior in strength and durability. Wiping cloths using ultrafine fibers have been proposed for the purpose of obtaining a large surface area, thereby increasing the adsorption surface and obtaining excellent cleaning power (JP-B-59-30419, JP-B-61-585).
No. 73, etc.). JP-B-59-30419 describes that both a hydrophilic stain and a lipophilic stain are removed by a combination of a lipophilic polymer and a hydrophilic polymer. However, such a combination of polymers has poor compatibility, and when a woven or knitted fabric is produced by compound spinning such a polymer, fibrillation is apt to occur in the steps from spinning, drawing to weaving, and stable processing is difficult. There was a problem.

Japanese Patent Publication No. 61-58573 discloses a method for obtaining a high-density woven or knitted fabric with little fraying or disturbed eyes, by jetting a high-pressure water stream onto a woven or knitted fabric made of ultrafine fibers, and by applying a yarn to the woven or knitted fabric. It is described that a woven or knitted fabric with less fraying and disturbed eyes can be obtained by entanglement of ultrafine fibers both between and within the yarn. However, since all of these use ultrafine synthetic fibers, there is a drawback that electrostatic charge due to friction between the object and the object to be cleaned is high.

It is well known that synthetic fibers generally have such a large electrostatic charge as compared to natural fibers, but the tendency is that the smaller the fineness of the fibers and the more the ultrafine fibers are used, the more the object to be cleaned. There is a problem that becomes more conspicuous because the contact area between them increases. In other words, even if the surface of the object to be cleaned is wiped off with ultrafine fibers, static electricity is generated on the surface of the object to be cleaned due to friction at that time, and minute dust in the air adheres to the surface of the object to be cleaned by the static electricity. That phenomenon occurs. In recent years, when used in the fields of the pharmaceutical industry, electronic precision industry, etc., which dislike dust generation and electrostatic charging, the conventional wiping cloth adheres dust due to electrostatic charging,
Problems such as element destruction due to discharge have occurred, and in many cases, inconvenience has been caused. On the other hand, synthetic fibers are liable to generate static electricity, and when used as clothing, garments may cling to the body, causing unpleasant discharge noise or causing dust to adhere easily. Research on making the material conductive or conductive has been conducted, and various methods have been proposed.

Specifically, a method of applying an antistatic agent to fibers by post-treatment, a method of coating an antistatic resin on the fiber surface, and a method of mixing an antistatic agent in the fibers and dispersing them in a streak shape. A method of causing the core portion of the core-sheath conjugate fiber to contain an antistatic or conductive substance has been proposed. When this method is applied to a fabric mainly composed of ultrafine fibers capable of obtaining excellent cleaning power, the antistatic agent and the coating resin may fall off due to friction or washing, or the fibers may be fibrillated. And a durable antistatic effect could not be expected. Further, the core-sheath conjugate fiber has too large a fiber diameter to obtain a sufficient cleaning power, and is not suitable for use as a wiping cloth.

[0006] Conventional antistatic fibers and conductive fibers have a dustproof property to keep out dust and dirt. On the contrary, it is considered that dust is mainly absorbed by electrostatic adsorption on the fiber surface. Although the use of antistatic and conductive fibers for wiping cloths has been proposed, the initial charge amount, so-called antistatic, low conductivity, and also low antistatic, continuous conductivity. Since it is short, the wiping durability is very poor.

It has been proposed to use carbon black as a conductive substance in the sense of increasing the initial conductivity.
Although it is implemented, it is often shunned in areas where design is required because of its black color. In the field of wiping cloths, in recent years, not only cleaning power but also design properties have been required, and wiping cloths having excellent cleaning power, dust resistance, washing durability, design properties, etc. have been required. I have.

[0008]

SUMMARY OF THE INVENTION The present invention relates to a wiping cloth having excellent cleaning power, dustproofness, washing durability, design and the like. It is intended to provide a wiping cloth having a certainty.

[0009]

According to the present invention, the fineness of the single fiber is 0.01 to 0.8 denier, and the fineness of the single fiber is not less than 20 degrees and not more than 1 degree.
3% by weight of a conductive fiber having an electric resistance of 9 × 10 ⁸ Ω / cm · f or less when 1 KV is applied to a cloth mainly composed of ultrafine fibers having a cross section having at least two angles of 20 ° or less. A wiping cloth characterized by having a charge density after washing 250 times of 7.0 μC / m ² or less.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The ultrafine fibers which are components of the wiping cloth of the present invention have at least two angles of not less than 20 degrees and not more than 120 degrees as compared with a generally used circular cross section or an approximate cross section. It is important that it has a cross section. By setting the cross section to have such an angle, it is possible to easily wipe off minute dirt that is difficult to wipe with a fiber (thread) having a conventional circular cross section. The wiping ability greatly differs depending on the angle of the yarn constituting the cloth with respect to the wiping surface. Fibers having a cross-sectional shape having at least two angles outside the above-mentioned angle have a reduced effect of wiping minute dirt even if they have a flat cross-sectional shape. A preferable angle is 30 degrees or more and 110 degrees or less.

In particular, it is preferable to have the above-mentioned angle and to have a flat cross-sectional shape from the viewpoint of wiping small dirt. This flat section has three or four corners,
Indicates that the flattening ratio (longest side / shortest side) is 1 or more, especially 1.5 or more. Since the wiping cloth of the present invention is formed of the ultrafine fibers (yarns) having the above-described angle, appropriate voids are generated between the yarns, and minute wiped-out dirt components are sequentially pushed into the voids. Until the limit, the wiped dirt does not adhere again. In addition, since it has an angle, it has a waist, and has wiping work durability.

The ultrafine fibers of the present invention have a single fiber fineness of 0.1.
It is from 01 to 0.8 denier, preferably from 0.05 to 0.5. If the single fiber fineness of the ultrafine fibers is less than 0.01 denier, the fiber strength becomes too weak, and the problem of cutting the fibers during cleaning and generating dust is likely to occur. On the other hand, if the single fiber fineness exceeds 0.8 denier, it is difficult to obtain sufficient cleaning power. Examples of the polymer constituting such ultrafine fibers include polyester, polyamide, polyolefin, and ethylene-
Vinyl alcohol-based copolymers, these copolymers, and mixtures of multiple components are preferred.

In the present invention, as described later, since one of the objects is to have good wiping properties for both water-based stains and oil-based stains, the ultrafine fibers are a mixture of hydrophobic fibers and hydrophilic fibers. It is preferred that The proportion of the hydrophilic fibers in the cloth (wiping cloth) is preferably 10 to 60% by weight, particularly preferably 10 to 50% by weight in view of wiping properties.

The ultrafine fibers having the single fiber fineness can be produced by a direct spinning method.
It is preferable to manufacture by the method described below. Specifically, sea-island composite fibers composed of two or more types of fiber-forming polymers, desealed fibers formed from splittable composite fibers, and the like are preferable. For example, a fibrillated fiber obtained by treating a multilayer laminated conjugate fiber composed of a polyester and a polyamide with benzyl alcohol or benzoic acid having swelling performance, or by stirring with hot water, on the polyamide. Fibrillated fiber obtained by treating a conjugate fiber with an aqueous alkali solution that is a polyester hydrolyzing agent, and fibrillated fiber obtained by treating the conjugate fiber with a combined system of false twist crimping and alkali weight reduction And the like. Further, there can be mentioned an ultrafine fiber obtained by dissolving and removing the sea component of a sea-island composite fiber in which a copolyester obtained by copolymerizing polystyrene or sulfoisophthalic acid with a polyester as an island component and a sea component as a sea component. The combination of the polymers constituting the composite fiber can be set according to the purpose.However, in order to impart wiping properties to both water-based stains and oil-based stains, a combination of a hydrophilic polymer and a lipophilic polymer, for example, polyester and Combinations of polyamide and the like are preferred.

Non-woven fabrics and woven or knitted fabrics are included as wiping cloths mainly composed of ultrafine fibers having the above-mentioned single fiber fineness and cross-sectional shape. Nonwoven fabrics include those obtained by subjecting a web composed of ordinary long fibers or short fibers to a treatment with a needle punch or a water punch, those formed by a melt blow method, and the like. It is not limited. In addition, plain woven fabric is usually applied, but satin weave, twill weave,
Any weave structure, such as satin weave and satin double weave, can be applied. As the knitting, any warp knitting or circular knitting structure can be applied. Such a cloth may contain a binder fiber or a resin as long as the object of the present invention is not hindered. In addition, the surface can be calendered, needles and watches
Punching or raising with a target may be performed. In the above-mentioned ultra-fine formation, after forming a cloth, a sea removal treatment or a separation / separation treatment may be performed to form an ultra-fine fiber.

The cloth is made of the above-mentioned ultrafine fiber 100.
%, But in order to satisfy the effects of the present invention, it is preferable that at least 20% by weight of the fibers constituting the cloth are the above-mentioned ultrafine fibers.

The conductive fibers to be mixed into the cloth at a ratio of 3% by weight or less have an electric resistance value of 9 × 10 when 1 KV is applied.
It is preferably ⁸ Ω / cm · f or less, and is preferably a white or colorless conductive fiber. By using such white or colorless conductive fibers, it is possible to apply the cloth to a wide range of design and aesthetic properties. In the present invention, a white or colorless conductive fiber means a fiber having a whiteness index of 25 or more. The whiteness index is a value measured in accordance with JIS L 1013B method, and can be measured and calculated by a method described later. A conductive fiber having such a whiteness index does not deteriorate in aesthetics even when mixed into a cloth.

As the conductive fiber according to the present invention, 1K
The type of the conductive fiber is not particularly limited as long as it is a white or colorless conductive fiber having an electric resistance value of 9 × 10 ⁸ Ω / cm · f or less when V is applied. It is preferable to use the conductive fiber described in JP-A-5-263318. That is, a fiber-forming polymer
Outermost layer (A) made of a polymer containing inorganic fine particles
This is a composite fiber composed of three layers: an intermediate layer (B) composed of layers and an innermost layer (C) composed of a polyamide layer containing conductive carbon black.

The conjugate fiber will be described briefly. The conductive carbon black contained in the innermost layer (C) is 10
Those having a specific resistance of ⁻³ to 10 ⁻² Ω · cm are preferable, and the type is not limited. Car in polymer
When the bon black is completely dispersed in a particulate form, the conductivity is generally poor, and when a chain structure called a structure is adopted, the conductivity is improved and the conductive carbon black is often formed. It is known. Therefore, in order to make the polymer conductive by the conductive carbon black, the structure of the carbon black is required.
It is important to disperse in the polymer so as not to destroy the structure. The conductive carbon black can be mixed and dispersed in the polymer by any known method. However, if an excessive shear stress acts on the conductive carbon black, the structure is destroyed and the conductivity is reduced. Mixing needs to be done with this in mind, as it can be significantly reduced.

The electrical conduction mechanism of the polymer layer containing conductive carbon black can be thought to be due to the contact of carbon black chains and the tunnel effect, but the former is generally the main. It is believed that. Therefore, the longer the chain of carbon black and the higher the density of the carbon black in the polymer, the higher the contact probability and the higher the conductivity. Considering the effect of carbon black to develop conductivity, the content of conductive carbon black in the innermost layer (C) is 15 to 50% by weight,
Particularly, 20 to 40% by weight is preferable. Even if the content exceeds 50% by weight, the effect of improving the conductive performance is not recognized, and the fluidity of the innermost layer (C) is rather deteriorated, and the spinnability of the conductive fiber is deteriorated.

As mentioned above, the carbon black must be dispersed in the polymer so as not to destroy its structure. For this purpose, a polyamide resin is most suitable as a polymer containing carbon black, and specific examples thereof include nylon 6, nylon 66, nylon 12, meta-xylene diamine nylon or a resin containing these as a main component. it can. Innermost layer (C)
The use of a polyamide resin as a polymer to form a carbon black improves the dispersibility of carbon black, prevents abnormal filter clogging during spinning, and improves the mechanical properties of the innermost layer (C). It is.

The intermediate layer (B) contributes to improvement of the coloring property of the innermost layer (C), and the intermediate layer (B) includes titanium dioxide,
It contains white pigments such as zinc oxide, magnesium oxide, aluminum oxide, silicon dioxide, barium sulfate, calcium carbonate, sodium carbonate, talc and kaolin, and white fillers. Taking into account the improvement of the coloring property of the innermost layer (C), that is, the hiding property, the substance contained in the intermediate layer (B) is preferably titanium dioxide or zinc oxide, and has an average particle size of 5 μm.
Hereinafter, those having a thickness of 1 μm or less are particularly preferable. Furthermore, the content of these inorganic fine particles is 10 to 80% by weight,
It is preferably 0 to 70% by weight from the viewpoint of concealability.

The polymer constituting the intermediate layer (B) is not particularly limited as long as it is a fiber-forming polymer. Specifically, polyamide resins such as nylon 6, nylon 66, nylon 12, and metaxylene diamine nylon; polyester resins such as polyethylene terephthalate, polybutylene terephthalate, and polyhexamethylene terephthalate; and polyethylene. And polyolefin resins such as polypropylene, polystyrene resins, polyurethane thermoplastic elastomers, polyester thermoplastic elastomers, and the like. Of these, polyamide resins, thermoplastic elastomers, and the like are preferable in terms of fluidity, heat resistance, and adhesion to inorganic fine particles when a large amount of inorganic fine particles are contained.

The polymer constituting the outermost layer (A) is preferably a thermoplastic polymer resin having a melting point of 150 ° C. or higher, and more preferably has excellent spinnability. Specific examples include polyester resins such as polyethylene terephthalate and polybutylene terephthalate, and polyamide resins such as nylon 6, nylon 66, and meta-xylene diamine nylon, among which polyethylene terephthalate, Polyester resins such as polybutylene terephthalate are preferred in view of workability.

The above-mentioned layer (A), layer (B) and layer (C)
The composite ratio of the fiber is 9 × 1 when the electric resistance value of the fiber when 1 KV is applied is 9 × 1.
0 ⁸ Ω / cm · f especially if the composite ratio so as to satisfy the following restriction is not, is a composite ratio such that fibers close to white or colorless concealing effect of the layer (B) is able to exert enough Is more preferable. Specifically, the longest diameter of the innermost layer (C) of the fiber cross section is x, the minimum thickness of the intermediate layer (B) is y,
When the minimum thickness of the outermost layer (A) is z, the following expression (1)
It is preferable that the composite form satisfies (2). 0.11 ≦ y / x ≦ 1.82 (1) 0.35 ≦ z / (x + y) (2)

Here, x indicates the longest diameter of the innermost layer (C). The shape of the layer (C) can be considered to be a circle, an ellipse, or a polygon in many cases. Indicates a diameter and a major axis, and in the case of a polygon, indicates the longest one including sides and diagonal lines. Also, y indicates the minimum thickness of the intermediate layer (B), which indicates the minimum thickness of the intermediate layer (B) formed by the outer periphery of the innermost layer (C) and the outer periphery of the intermediate layer (B). And z
Indicates the minimum thickness of the outermost layer (A), which is the intermediate layer (B)
And the minimum thickness of the outermost layer (A) formed by the outer periphery of the outermost layer (A).

In the above-described composite shape of the conductive fiber, the innermost layer (C) and the intermediate layer (B) are continuous in the longitudinal direction of the fiber, and the intermediate layer (B) is provided around the innermost layer (C). It is sufficient that the outermost layer (A) has a fiber cross section located at the outer periphery thereof, and the others are not limited. As described above, there are various cross-sectional shapes of the innermost layer (C) and the intermediate layer (B), and it is particularly preferable that the innermost layer (C), which is a conductive polymer layer, has a shape having an acute angle or irregularities in terms of static elimination performance. Things.
The cross-sectional shape of the conductive fiber may be circular or non-circular.

In the above-mentioned conductive fiber, the innermost layer (C) may not be completely covered with the intermediate layer (B), or the intermediate layer (B) may not be completely covered with the outermost layer (A). You may. If it is white or colorless, the innermost layer (C) and the intermediate layer (B) may be exposed on the fiber surface.

The conductive fiber can be obtained by a conventionally known method for producing a composite fiber. For example, 500-2500
A method of performing normal spinning at a speed of m / min, and performing stretching and heat treatment, a method of performing spinning at a speed of 1500 to 5000 m / min, and subsequently performing a stretching and false twisting process, 5000 m / min.
Any production method such as a method of spinning at a high speed of at least minutes and omitting the stretching step can be adopted.

The fineness of single fibers of the above-mentioned conductive fibers is preferably the same as the fineness of single fibers of the fine fibers mainly constituting the cloth, but may be larger than the fine fibers. However, it is preferably 15 denier or less in consideration of the wiping workability as a cloth.

In the present invention, it is preferable that the conductive fiber be mixed in the cloth in an amount of 3.0% by weight or less, particularly in the range of 0.2 to 2.0% by weight, to prevent dust and prevent reattachment of dust and dust. It is preferred in terms of washing properties and washing durability. 3 mixed
Even if it exceeds 10% by weight, the effect of improving the wiping property as a cloth and the property of preventing the reattachment of dust and dirt is not recognized. The method of mixing the conductive fibers into the cloth is not particularly limited, and the fibers or yarns constituting the cloth may be mixed with conductive fibers, or may be knitted or woven. When the cloth is a woven fabric, conductive fibers may be inserted into at least one of the warp and the weft at appropriate intervals. The conductive fiber may be mixed with the ultrafine fiber or the cloth made of the ultrafine fiber in any form such as a monofilament form, a multifilament form, and a cut staple form.

As described above, a cloth mainly composed of microfibers having a specific cross-sectional shape is obtained by mixing conductive fibers having a specific electric resistance at a ratio of 3.0% by weight or less, and having a cross section of 250 times. Has a charge density after washing of 7 μC /
m ² or less, it is possible to maintain a high static elimination property. Therefore, not only the dust resistance and the stain resistance, but also the whiteness maintenance property of the fabric,
That is, it is possible to obtain a cloth excellent in design, durability in wiping work, and prevention of reattachment of dust.
The conductive fiber used in the present invention can be dyed even though the conductive carbon black is used, and can be dyed in the same color as the ultrafine fiber. The use area as a wiping cloth is expanded.

[0033]

EXAMPLES The present invention will be described below in detail with reference to examples, but the present invention is not limited to these examples. Each measured value in the examples is a value measured and calculated by the following method. (1) Measurement of angle in cross section of ultrafine fiber A photograph of the cross section of the fiber is taken with an electron microscope, the cross section of any 20 fibers is copied on paper, and three or four angles are measured. The average value of the number of angles in the range and the average value of the individual angles are shown. (2) Electric resistance value of conductive fiber After cutting the sample to a length of 10 cm and applying a conductive paint (doteite) to the cut surface to fix the end of the fiber, the end was used as an electrode at an applied voltage of 1 KV. The electric resistance was measured.

(3) Whiteness index of the conductive fiber The whiteness index was determined in accordance with JIS L 1013B method. That is, a tubular knitted fabric of a sample was prepared, and the sample was folded in eight, and the reflectance at a wavelength of 450 nm and 550 nm with respect to a standard white plate was measured using a spectrophotometer (type 307, manufactured by Hitachi, Ltd.). An index was calculated. Whiteness index = 4R ₁ -3R ₂ R ₁ : Reflectance at 450 nm R ₂ : Reflectance at 550 nm (4) Evaluation of cloth wiping performance The slide glass on which the contaminant was adhered was subjected to a friction tester (J
The test piece was temporarily bonded to a flat test table of a testing machine based on IS 10823, and wiped off with a friction element fitted with a test cloth. Wiping load is 200g, wiping width is 20
The wiping was performed several times under the conditions of 100 mm / mm and the wiping stress was 100 g / mm, and the transmittance before and after the wiping was measured. Wiping rate (%) = [(Wn−W ₀ ) / (Wb−)
W ₀ )] × 100 Wb: transmittance of slide glass at 380 nm or 580 nm Wn: transmittance after wiping W ₀ : transmittance before wiping [contaminant] a. Cleaning power for nicotine Place slide glass (20 pieces) horizontally in the fumigation box,
Approximately 20 cigarettes (pieces) were fumigated, and contaminants were attached mainly to nicotine. Visible light transmittance is 20%
It was adjusted to be as follows. b. Cleaning power for lubricating oil A frame is set on the slide glass, and 30 cm of commercially available lubricating oil is applied.
Was sprayed from the distance of 3 seconds to obtain a sample. c. Cleaning power for glue Glue (0.5 g / cm ² ) consisting of 10 g / l of cone starch was applied to a slide glass.

(5) Charge Density of Cloth RISTR of electrostatic safety guideline issued by Ministry of Labor Safety Research Institute
78-1. (Measurement after standing in a room at 22 ° C. and 30% RH for 24 hours) Washing was carried out at a bath ratio of 1:30, a standard amount of a synthetic detergent (weakly alkaline) was added, and washing was performed at 40 ° C. for 5 minutes. The process of pooling and rinsing twice with 1:30 water and dehydrating for 5 minutes was repeated 250 times. (6) As shown in FIG. 1, the frictional band voltage measuring device is such that a resin flat plate (acrylic plate or polyethylene plate) is placed on a metal base, and a surface voltmeter (Statiron M: rotating sector type) is provided behind the resin flat plate. / 1 to 100 KV), and the charged voltage of the resin flat plate after wiping can be measured. Washing was performed by the method described in the above (5).

(7) Discharge Phenomena Discharge phenomena in the wiping process are as follows. Discharge noise is generated by a loop antenna installed behind a resin flat plate, and discharged by an analyzing recorder (Yokogawa Electric 3655E / DC RANGE2.0V). Can be observed. The evaluation was made based on the charged voltage of the resin plate when the sample was wiped on the resin plate and the discharge phenomenon (crackling discharge noise) in the wiping process. The conditions were 22 ° C., 30% RH, and the number of times of friction was 10. In addition, when the static electricity generated in the wiping process is measured only by the charged voltage, if the charged voltage exceeds a certain value, a discharge phenomenon (a crackling sound) occurs in the wiping process, and as shown in FIG. It can be seen that the phenomena may be different, and it is not possible to evaluate the static electricity generated in the wiping process by the charged voltage alone. Judgment of discharge phenomenon A : Neither discharge sound nor discharge pulse is observed. ：: no discharge sound is observed, but a discharge pulse is observed. Δ: Both discharge sound and discharge pulse are observed. ×: Both discharge sound and discharge pulse are remarkable. Washing was performed by the method described in (5) above.

(8) Evaluation of static elimination performance The distance between the charged sphere and the discharge sphere is set to 1 cm, the charged sphere is charged using an electromotive machine, and a discharge is generated. The presence or absence of discharge when the sample was brought close to the charged sphere was observed.
Stopping the discharge means that static elimination is being performed. O: Discharge stopped X: Discharge continued The washing was performed by the method (5).

Example 1 First, according to the method described in JP-A-5-263318, the electric resistance value was 3.0 × 10 ^{7 under the} following conditions.
A conductive fiber of 25 denier / 2 filaments of Ω / cm · f was obtained. Outermost layer (A) ··· Polyethylene terephthalate containing 0.5% by weight of titanium dioxide having an average particle size of 0.18 µm [Intrinsic viscosity: 0.65 (mixed solution of phenol / tetrachloroethane, etc. by weight) Measured at 30 ° C. using an intermediate layer)] Intermediate layer (B) Nylon 6 containing 10% by weight of titanium dioxide having an average particle size of 0.2 μm [1013BK manufactured by Ube Industries, Ltd.] Innermost layer (C) ... Nylon 6 containing 35% by weight of conductive carbon black [1013BK manufactured by Ube Industries, Ltd.] Composite ratio (% by weight) ... Layer (A) / layer (B) / layer (C ) = 70/25/5

Next, nylon 6 [1013 manufactured by Ube Industries, Ltd.]
BK] and polyethylene terephthalate having an intrinsic viscosity of 0.70
And melt-extruded with separate extruders, and weighed with a gear pump so that the composite ratio becomes nylon 6: polyethylene terephthalate = 33: 67 (weight ratio).
It was fed into a spin pack, discharged at a die temperature of 290 ° C., and wound up at a speed of 1000 m / min. Then, drawing was carried out at a magnification of 2.9 with a roller heater at 75 ° C, and heat setting was carried out with a plate heater at 130 ° C to obtain a drawn yarn of 75 denier / 24 filaments. The cross section of the yarn was a vertically split cross section (11-layer alternating bonding type). Subsequently, the drawn yarn was subjected to false twisting at a number of false twists of 3390 T / M and a temperature of 170 ° C. to perform a splitting treatment. The single fiber fineness of the obtained crimped yarn made of polyester and polyamide is about 0.5.
It was 3 denier. A tubular knitted fabric was prepared using the ultrafine fibers and subjected to relaxation, washing with water, drying, presetting, alkali reduction, washing with water, and drying to obtain a fabric. 0.9% by weight of the above-mentioned conductive fiber was mixed into this cloth, and the performance as a wiping cloth was evaluated. The results are shown in Tables 1 and 2.

Example 2 A cylindrical knitted fabric was prepared in the same manner as in Example 1 except that the single fiber fineness of the crimped yarn after the splitting treatment was changed to 0.50 denier. And dried to obtain a fabric.
0.9% by weight of the above-mentioned conductive fiber was mixed into this cloth, and the performance as a wiping cloth was evaluated. The results are shown in Tables 1 and 2. Since the single fiber fineness of the ultrafine fibers after the splitting treatment was increased, the wiping performance was slightly lower than that of the cloth obtained in Example 1.

Example 3 A tubular knitted fabric was prepared in the same manner as in Example 1 except that the proportion of the hydrophilic fibers in the ultrafine fibers was changed to 49% by weight, and various treatments were performed, followed by drying. I got 0.9% by weight of the above-mentioned conductive fiber was mixed into this cloth, and the performance as a wiping cloth was evaluated. The results are shown in Tables 1 and 2.

Example 4 In the same manner as in Example 1, except that the amount of the inorganic fine particles to be contained in the intermediate layer of the conductive fiber was changed to 70% by weight, a tubular knitted fabric made of ultrafine fibers was prepared. And dried to obtain a fabric. 0.9% by weight of conductive fibers in which the content of the inorganic fine particles to be contained in the intermediate layer was changed was mixed into this cloth, and the performance as a wiping cloth was evaluated. The results are shown in Tables 1 and 2.

Example 5 In Example 4, instead of nylon 6, an ethylene-vinyl alcohol-based copolymer (ethylene content: 44)
A woven fabric was prepared in the same manner except that a composite fiber was obtained using mol%, a saponification degree of 99%, and Kuraray's E-105), and an ultrafine fiber was obtained by performing a division treatment. The conductive fibers used in Example 4 were mixed into this cloth to evaluate the performance as a wiping cloth. The results are shown in Tables 1 and 2.

Example 6 A fabric was prepared in the same manner as in Example 5, except that the single fiber fineness of the ultrafine fibers was changed to 0.19 denier. The conductive fibers used in Example 4 were mixed into this cloth to evaluate the performance as a wiping cloth. Table 1 shows the results
And Table 2.

Example 7 Polyethylene terephthalate (intrinsic viscosity 0.61) and polyethylene terephthalate (intrinsic viscosity 0) copolymerized with 2.5 mol% of 5-sodium sulfoisophthalic acid and 8% by weight of polyethylene glycol 68), a composite fiber having a vertically split cross-sectional structure of 68) is obtained, and then an alkali weight reduction process is performed to dissolve and remove the former copolymerized polyethylene terephthalate to obtain an ultrafine fiber made of polyethylene terephthalate. Obtained. Using the ultrafine fibers, a fabric was prepared in the same manner as in Example 1, and the conductive fibers used in Example 1 were mixed into the fabric to evaluate the performance as a wiping cloth. The results are shown in Tables 1 and 2. Since it did not contain hydrophilic fibers, the wiping performance was slightly inferior to the wiping cloth obtained in Example 1.

Comparative Example 1 In Example 1, the conductive fiber had an electric resistance of 5 ×
In the same manner except that fibers of 10 ¹¹ Ω / cm · f were used, a tubular net made of ultrafine fibers was prepared, subjected to various treatments, and dried to obtain a fabric. The above-mentioned conductive fibers were mixed into this cloth, and the performance as a wiping cloth was evaluated. The results are shown in Tables 1 and 2. Since the conductive fiber with a small electric resistance value is mixed, the charge amount is high,
There was no static elimination performance, for example, discharge noise was observed.

Comparative Example 2 In the same manner as in Example 1, except that the conductive fiber was not mixed into the cloth, a tubular net made of ultrafine fibers was prepared, subjected to various treatments, and dried to obtain a cloth. The performance of this wiping cloth was evaluated. Tables 1 and 2 show the results.
Shown in The wiping performance was high, but after wiping the surface of the surface to be cleaned, some time after the dust in the air adhered to the surface to be cleaned.

Comparative Example 3 In the same manner as in Example 1, except that high-density polyethylene was used as the polymer for forming the innermost layer (C) of the conductive fibers, a tubular knitted fabric made of ultrafine fibers was prepared. And dried to obtain a fabric. The above-mentioned conductive fibers were mixed into this cloth, and the performance as a wiping cloth was evaluated. The results are shown in Tables 1 and 2. Although the initial wiping performance was excellent, the static elimination performance after 250 washes was markedly reduced, and it could be said that there was no durability.

Comparative Example 4 A tubular knitted fabric made of ultrafine fibers was prepared in the same manner as in Example 1 except that the single fiber fineness of the ultrafine fibers was changed to 0.90 denier, subjected to various treatments, and dried. A fabric was obtained. Conductive fibers were mixed into this cloth, and the performance as a wiping cloth was evaluated. The results are shown in Tables 1 and 2. It can be seen that when the single fiber fineness of the ultrafine fibers increases, the wiping performance significantly decreases.

Comparative Example 5 In Example 1, the core was made of nylon 6 containing 35% by weight of conductive carbon black as the conductive fiber, the sheath was made of polyethylene terephthalate, and the core: sheath = 10: 90.
(Weight ratio) A tubular knitted fabric made of ultrafine fibers was prepared in the same manner except that the conductive fibers having a two-layer structure (weight ratio) were used, subjected to various treatments, and dried to obtain a fabric. The above-described conductive fibers having a two-layer structure were mixed into the cloth, and the performance as a wiping cloth was evaluated. The results are shown in Tables 1 and 2. Although having the durability of the static elimination performance, the color of the conductive fiber was conspicuous, and the design was poor.

Comparative Example 6 5-sodium sulfoisophthalic acid 2.5 as a sea component
Mol%, polyethylene glycol 8 wt% copolymerized polyethylene terephthalate (intrinsic viscosity 0.61), and polyethylene terephthalate (intrinsic viscosity 0. 1) as an island component.
68) is used to produce sea-island composite fibers (17 islands).
Then, the polyethylene terephthalate copolymer as a sea component was dissolved and removed by alkali reduction treatment, and the polyethylene terephthalate having a single fiber fineness of 0.29 denier and a round cross section was used.
A very fine fiber was obtained. A tubular knitted fabric was prepared using the ultrafine fibers, subjected to various treatments and dried to prepare a fabric. The conductive fibers used in Example 1 were mixed into this cloth, and the performance as a wiping cloth was evaluated. Table 1 shows the results
And Table 2. Even ultrafine fibers had poor wiping performance due to their round cross-sectional shape.

[0052]

[Table 1]

[0053]

[Table 2]

[0054]

The wiping cloth of the present invention has a high static elimination effect, so that even after wiping off dust and dirt, dust and dirt in the air do not adhere to the surface of the object to be cleaned. Can be held. In addition, this performance is maintained after 250 washes, resulting in a very durable wiping cloth.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an apparatus for measuring a triboelectric voltage and a discharge phenomenon.

FIG. 2 is a diagram showing one state of a discharge pulse.

FIG. 3 is a diagram showing a discharge pulse of a cleaning cross obtained in Example 1.

FIG. 4 is a view showing a discharge pulse of a cleaning cross obtained in Comparative Example 2.

[Description of Signs] 1: Analyzing recorder (discharge noise recorder) 2: Charger recorder 3: Surface electrometer 4: Loop antenna 5: Probe 6: Resin flat plate

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masao Kawamoto 892 Sakuhi-shi, Saijo-shi, Ehime Pref.

Claims (5)

[Claims] 1. A fabric mainly composed of ultrafine fibers having a single fiber fineness of 0.01 to 0.8 denier and having a cross section having at least two angles of 20 to 120 degrees. The electric resistance value when applying 1KV is 9 × 10 ⁸ Ω
/ Cm · f or less by 3% by weight or less, and the charge density after washing 250 times is 7.0 μC / m ^2.
A wiping cloth characterized by the following. 2. A conductive fiber comprising a polyamide layer containing conductive carbon black as an innermost layer, a polymer layer containing at least 10% by weight of inorganic fine particles as an intermediate layer, and a conductive fiber comprising a fiber-forming polymer. The wiping cloth according to claim 1, wherein the wiping cloth is a conductive fiber having a three-layer structure including an outer layer. 3. The wiping cloth according to claim 1, wherein the proportion of hydrophilic fibers having a single fiber fineness of 0.01 to 0.8 denier in the fabric is 10 to 60% by weight. 4. The wiping cloth according to claim 3, wherein the hydrophilic fiber is a polyamide fiber. 5. The wiping cloth according to claim 3, wherein the hydrophilic fiber is a fiber comprising an ethylene-vinyl alcohol copolymer.