JPH073571A - Knitted fabric - Google Patents

Abstract

PURPOSE:To provide a knitted fabric capable of positively absorbing near- infrared rays of sunlight to raise the thermal insulating ability of the back surface thereof, also excellent in antistatic effect in low-humidity circumstances, and good in anti-pilling nature. CONSTITUTION:The objective knitted fabric has the following characteristics: (1) containing 3-15wt.% of electrically conductive fibers, (2) the whole carbon black content: >=0.1wt.%, and (3) electrostatic voltage due to friction: <=2KV. Said electrically conductive fibers are such that a carbon black-contg. antistatic polymer is oriented in a muscle-like way in the single fibers and at least partly exposed on the surface layer of the fibers and consist of a kind of acrylic fibers, having an electrical resistivity of 10-10<6>OMEGA.cm. For a cylindrical knitted fabric 200g/m<2> in basis weight made from said electrically conductive fibers along, the maximum spectroscopic reflectance in the wavelength region of 760-2000mum is <=10%.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a knitted fabric excellent in heat retention and antistatic property based on its spectral heat absorption property, and more specifically, to a fabric in which carbon black-containing conductive fibers are mixed-spun, mixed-fiber interwoven or cross-woven. The present invention relates to a knitted fabric suitable for cold-weather clothing, sports and leisure clothing, which has both a spectral heat absorption heat retention effect based on knitted solar heat selective absorption characteristics and an antistatic effect having little humidity dependency.

[0002]

2. Description of the Related Art Heretofore, as a means for improving the heat retaining property of a knitted fabric, there have been known hollow fiber fabrics utilizing the heat insulating property of air, and those raising the air content of the fabric by raising the fabric surface. However, since the cloth itself is thick, it has a drawback that it is heavy and bulky and its free movement is hindered.
Recently, it has been known in JP-A-1-132816 that a specific ceramic, for example, zirconium carbide is contained in a fiber to positively utilize solar heat to form a heat-retaining knitted fabric. The heat storage and heat retention effects are not necessarily good because they must be mixed in the parts.

Japanese Patent Laid-Open No. 3-97959 discloses a heat-retaining fiber that absorbs solar heat by modifying acrylic fibers to which copper ions or the like are attached. And the washing resistance is not always good.

Further, conventionally, in order to prevent static electricity generation, antistatic treatment with a surfactant, a method of using antistatic fiber blended with a hydrophilic polymer, a method of preventing static electricity by mixing metal fibers, plating There are known a method of using an organic fiber coated with a metal by vapor deposition or an organic fiber coated with a resin containing carbon particles, and a method of using an antistatic fiber using a polymer containing carbon black.

[0005]

However, the fibers supplied in the prior art and the cloths obtained from them have the sole purpose of retaining heat or antistatic property. It did not have both positive heat retention and antistatic properties.

[0006] Therefore, the heat-retaining cloth does not solve various problems such as static electricity, in particular, wrapping of clothes on the body in a low humidity environment, electric shock due to human body electrification, undressing discharge noise, dust adhesion and the like.

On the other hand, since the antistatic fabric is used for the purpose of preventing static electricity, for example, the outer surface of the fabric is white or has good dyeability, and the antistatic fiber is used as the inner surface. Although we have made ingenuity such as fabric configuration with fibers arranged, we do not have a fabric configuration that actively and selectively absorbs solar heat to improve heat retention, but there is still a problem that the heat retention on the back side of the fabric is low. It was

The object of the present invention is to solve the problems of the conventional heat insulating cloth and antistatic cloth at the same time, and the cloth itself actively and selectively absorbs solar heat to enhance the heat insulating property and reduce the heat retention. An object of the present invention is to provide an excellent knitted fabric having both a spectral heat absorption heat retention property and an antistatic property, which has a high antistatic effect in a humid environment.

[0009]

In order to solve the above problems, the present invention has the following constitution. That is, 3 to 15% by weight of conductive fibers are mixed, the total amount of carbon black contained in the knitted fabric is 0.1% by weight or more, and the frictional electrification voltage is 2 KV or less. The fiber is made of an acrylic fiber in which a carbon black-containing antistatic polymer is linearly oriented in a single fiber, and the antistatic polymer is at least partially exposed on the surface layer of the fiber, and the electric resistivity of the conductive fiber is 10 to 10 ⁶ A knitted fabric having a maximum spectral reflectance of 10% or less in a wavelength region of 760 mμ to 2000 mμ of a tubular knitted fabric having a basis weight of 200 g / m ² knitted from only the conductive fiber filaments. is there.

The present invention will be described in detail below.

The conductive fiber used in the knitted fabric of the present invention does not contain a metal, but is made of an acrylic polymer which is essentially an organic compound and has solar heat selective absorption characteristics and conductivity. Acrylonitrile (AN) is added to a block polyetherester copolymer having an acrylic polymer and an antistatic polymer that is miscible with the acrylic polymer but is not compatible with the polymer. It consists of grafted polymer, and many antistatic polymers are dispersed in acrylic polymer along the fiber axis in the form of long and slender stripes. ) And carbon black fine particles having excellent conductivity are uniformly dispersed.

The electrical resistivity of the polymer itself obtained by grafting acrylonitrile onto a block polyether ester type copolymer with polyalkylene glycol is 10 ⁷
Ω · cm or less, more preferably 10 ⁵ Ω · cm or less. The mixing ratio of the antistatic polymer and the acrylic polymer is preferably such that the antistatic polymer is blended in an amount of 5 to 40%, preferably 10 to 35%, based on the weight of the mixture, and when the amount is less than 5%, solar heat selection is performed. The amount of carbon black required for absorption is insufficient, and the antistatic property is not sufficient. On the other hand, when it exceeds 40%, the spinnability is deteriorated and a fiber having good physical properties cannot be obtained, which is not preferable.

Next, as a substance having selective absorption of solar heat and conductivity, a near infrared region (760 mμ to 2000 m) is used.
Particles having a low spectral reflectance in the wavelength region of μ), particularly carbon black particles having the lowest spectral reflectance, are preferable.
Carbon black particles having an average particle size of 0.2 μ or less, preferably 0.05 μ or less are used. The blending ratio of carbon black particles is about 15 to 150% by weight based on the antistatic polymer before containing the carbon black.
Further, it is preferably about 2 to 20%, more preferably 4 to 15%, based on the weight of the fiber. When the amount is less than the above range, the solar heat absorbing ability and the antistatic ability are insufficient, and when the amount exceeds this range, the mechanical properties of the fiber are deteriorated, which is not preferable.

The above-mentioned carbon black-containing conductive fiber is prepared by mixing a carbon black-containing antistatic polymer in an acrylic polymer to produce various known acrylic fibers, for example, wet spinning, dry spinning, dry wet spinning and the like means. It is possible to manufacture by. What is important here is that the carbon black-containing antistatic polymer is dispersed and oriented in a streak pattern in the acrylic polymer, and the carbon black particles are present in a streak pattern in the acrylic fiber. Fibers with a structure in which carbon black particles are simply uniformly dispersed in an acrylic polymer require an extremely large amount of carbon black particles to be added in order to improve antistatic property, which reduces spinnability and facilitates the formation of carbon black particles. Problems such as dropping out occur. Further, the obtained fiber has a problem that it looks very black and the washing resistance is extremely poor. That is, only when the carbon black particles are present in a streak shape in the acrylic fiber, it is possible to maintain the solar heat selective absorption capacity and the conductive performance in a well-balanced manner.

The thus obtained fiber which selectively absorbs solar heat and has electrical conductivity is usually black because of carbon black particles.

Generally, what is called antistatic property has a specific electrical resistance of the fiber bundle of about 10 ⁶ to 10 ¹⁰ Ω · cm.

The fineness of the carbon black-containing conductive fiber used in the present invention is 1 to the fineness of ordinary clothing fibers.
10 denier, preferably 1.5 to 7 denier, wherein the antistatic polymer containing carbon black particles is composed of carbon black-containing acrylic fiber at least partially exposed on the fiber surface layer, and the electricity of the carbon black-containing fiber is Specific resistance is 10 to 10 ⁶ Ω · cm, preferably 1
0 to 10 ⁴ Ω · cm, and 7 of a tubular knitted fabric having a basis weight of 200 g / m ² knitted only from the conductive fiber filaments.
The maximum spectral reflectance in the wavelength region of 60 mμ to 2000 mμ is 10% or less, preferably 5% or less, more preferably 3% or less. In addition, this tubular knitted fabric is 3
It shall be knitted using conductive fiber filaments of 00 denier-48 filaments.

The carbon black-containing conductive fiber is mixed in the knitted fabric in an amount of 3 to 15% by weight, preferably 4 to 12% by weight, and the total amount of carbon black in the knitted fabric is 0.1% by weight or more. , Preferably 0.2% by weight or more.

When the mixing ratio of the carbon black-containing conductive fiber in the knitted fabric is less than 3% by weight, both functions of the spectral heat absorption and heat retention and the antistatic property are insufficient. On the other hand, when the mixing ratio exceeds 15% by weight, not only is there an inconvenience that the types of products are limited due to the blackening of the resulting knitted fabric, but also the effect of improving heat retention and antistatic property is saturated. Therefore, there is a problem that the cost is further increased.

The knitted fabric of the present invention has a frictional electrification voltage of 2 KV or less. If the frictional electrification voltage exceeds 2 KV, it is impossible to prevent the clothing from wrapping around the body under low humidity, electric shock due to human body electrification, undressing discharge noise, etc. It is not possible to obtain a knitted fabric that has both functions. From the viewpoint of further improving antistatic performance, the triboelectric charge density of the knitted fabric should be 3 μm.
Coulomb / m ² or less is preferable.

The knitted and woven fabric of the present invention is particularly suitable for use in the sunlight 7
It has excellent heat absorption in the near infrared wavelength region of 60 mμ to 2000 mμ, and the maximum value of the spectral reflectance in this wavelength region is preferably 40% or less, more preferably 30% or less, and particularly preferably 20% or less.

The fiber material which is the main constituent of the knitted fabric is not particularly limited, but acrylic fibers which are lightweight, bulky and have good heat retention are preferably used. Among them, acrylic fiber having anti-pill property is preferable. In addition to these, polyester fibers and nylon fibers having excellent practical properties are also preferably used according to the application.

It should be noted that natural fibers such as wool, and filaments made of various other materials, within the range not impeding the object of the present invention,
You can mix staples. Further, as the acrylic fiber, there is no problem even if a bulky fiber such as a composite fiber, a porous fiber or a hollow fiber is mixed.

The method of mixing the carbon black-containing conductive fibers in the knitted fabric is not particularly limited, and the knitted fabric may be mixed evenly in both warp and weft knits, and intermittently in the form of horizontal stripes or vertical stripes. The woven fabric may be any ordinary method such as single weaving or double weaving. It is desirable that the knitted fabric is arranged more on the outer surface than on the inner surface, because the solar heat absorption effect in the near infrared region is better.

The present invention will be specifically described below with reference to examples.

The evaluation method used in the present invention is as follows.

(1) Spectral heat absorption heat retention In a room at 20 ° C. and 65% RH, a white bulb of a reflex lamp 300 W for photography was used as an energy source. Install a temperature sensor (thermocouple) under the sample for evaluation, and turn on the reflex lamp from above 25 cm above the sample.
The back surface temperature of the sample was measured after 5 minutes.

(2) Spectral reflectance The reflectance at a wavelength of 300 mμ to 1200 mμ was determined using a spectrophotometer.

(3) Electrical resistivity (fiber bundle) Approximately 2000 denier, 10 cm sample at 30% RH, 20
Both ends are grasped in an atmosphere of ° C, the electric resistance (R) of 100 V is measured, and the electric specific resistance (ρ) is obtained by the following formula.

Ρ = (R × denier) / (9 × 10 ⁶ × specific gravity) (Ω · cm) (4) Antistatic property (fabric) A. Friction electrification charge density Knitted fabric sample was washed with Kao Co., Ltd. laundry soap "Zab" under normal household washing conditions (electric washing machine, strong condition, 40 ° C, 5
Min, 0.2% concentration), washed 20 times with air, and make a test piece of 25 cm in length and 25 cm in width. This one 20
After leaving it in the atmosphere of ℃, 30% RH for more than 24 hours, rub it strongly with acrylic knitted fabric under this temperature and humidity condition (10 times for 1 second each time), and immediately put a test piece on Faraday of appropriate size. Place in a cage and measure the amount of charge on the test piece. The charge amount is converted per 1 m ² of the sample, and this is defined as the triboelectric charge amount (μc / m ² ).

B. Friction electrification voltage The test piece was repeatedly washed under the same conditions as the triboelectrification charge density, dried, and allowed to stand in an atmosphere of 20 ° C. and 30% RH for 24 hours or more. Under this temperature and humidity condition, a rotary static tester (Kosuke The test piece was attached to a rotating body (made by Shokai Co., Ltd.) (400 rpm) and rubbed against a cotton fabric (gold width No. 3, after refining processing), and the potential (KV) charged to the test piece after 1 minute
To measure.

Test piece: 8 cm × 5 cm (friction area 4 cm × 25
cm) Friction cloth: 15 cm x 2 cm (tension 500 g) Contact pressure between test piece and friction cloth: 2 mm Distance between test piece and current collector: 12 mm (5) Anti-pill property Measured by JIS L 1076 ICI method (5 hours) .

(6) Hue of knitted fabric ◎: Good (black is not visible) ○: No problem (black is not noticeable) △: Almost no problem (a little gray appears) ×: Quite black (black) I am worried about it) XX: It looks black (black type)

[0034]

【Example】

Reference Example 1 94.2 mol% of acrylonitrile (AN), 5.5 mol% of methyl acrylate and 0.3 mol% of sodium methallyl sulfonate were added to dimethyl sulfoxide (D).
Solution polymerization in MSO), solution viscosity 200 poise / 45
Block poly having a composition of 25% by weight of polyethylene adipate containing 75% by weight of Furnace Black # 40 (manufactured by Mitsubishi Kasei Co., Ltd.) in stock solution (A) having a concentration of 22.5% by weight and 75% by weight of polyethylene glycol. A polymer DMSO solution (B) obtained by graft-polymerizing an ether ester (70 parts) with AN (30 parts) was mixed so that the amount of furnace black added to the fiber was 7.2% by weight, and the mixture was mixed normally. A carbon black-containing conductive fiber was obtained by a spinning method. When the block polyether ester was mixed and spun with an AN polymer, it had miscibility but no compatibility, and many strands were stretched and oriented in the AN single fiber. The fineness of the obtained fiber is 2.5 denier and the dry strength is 2.
3 g / d, dry elongation 28%, knot strength 1.9 g / d, knot elongation 11%, boiling water shrinkage 2.2%, electrical resistivity 2.5 × 10 ³ Ω · cm However, there was no temperature / humidity dependency and the conductive performance was good.

(Examples 1 to 4, Comparative Examples 1 to 4) Reference Example 1
The carbon black-containing conductive fiber obtained in 1. was cut into 51 mm, and the anti-pill "Trelon" T-24 manufactured by Toray Industries, Inc.
622 2d × 51 mm was mixed and the resulting yarn was spun into fibers to obtain a spun yarn with a mixed ratio of 1/48 by changing the mixing ratio. This spun yarn is knitted into a circular knitted fabric with an 18G milling machine and treated with boiling water for 60 minutes or black dyeing (dye: Kayacryl black 5% owf, acetic acid 0.5 cc / L, 100 ° C x 60).
Min) to obtain a knitted fabric having a basis weight of 225 g / m ² (Examples 1 to 4).

Table 1 shows the evaluation results of the spectral heat absorption and heat retention of the knitted fabric, the antistatic property and the anti-pill property. For comparison, a knitted fabric with a low carbon black-containing conductive fiber content,
The evaluation results of a remarkably large number of knitted fabrics and knitted fabrics composed of only the (A) polymer (Comparative Examples 1 to 4) are shown.

[0037]

[Table 1] As the results show, the knitted fabrics of Examples 1 to 4 had low spectral reflectance, good spectral heat absorption, excellent antistatic property, good anti-pill property, and good hue.

Reference Example 2 In the same manner as in Reference Example 1, carbon black-containing conductive fibers were mixed so that the amount of furnace black added in the fibers was 2.8% by weight.
Similar to the carbon black-containing conductive fiber obtained in Reference Example 1, a large number of carbon black particles in the single fiber were oriented in a streak pattern in this fiber. The resulting fiber has a fineness of 2.4 denier, a dry strength of 2.5 g / d, a dry elongation of 29%, a knot strength of 2.1 g / d, a knot elongation of 13%, and a boiling water shrinkage ratio of 2.4%.
The electrical resistivity was 2 × 10 ⁴ Ω · cm, and there was no temperature / humidity dependency, and the conductivity was good.

(Example 5, Comparative Examples 5 to 8) The carbon black-containing conductive fiber obtained in Reference Example 2 was cut into 51 mm, and Toray Industries, Inc. anti-pill "Trelon" T-2462 2
A mixed yarn of d × 51 mm was obtained, and a spun yarn with a metric count of 1/48 was obtained by ordinary worsted spinning. A circular knitted fabric was knitted from this spun yarn using an 18G milling knitting machine, and the raw fabric was treated with boiling water for 60 minutes to obtain a knitted fabric having a basis weight of 198 g / m ² (Example 5).

Table 2 shows the evaluation results of the spectral heat absorption and heat retention of the knitted fabric, the antistatic property and the anti-pill property. For comparison, the amount of the furnace black directly in the stock solution (A) used in Example 1 was 2.5% by weight in the fiber without using the polymer in which AN was grafted to the block polyether ester.
The mixture was uniformly mixed so as to be 5% by weight, and a carbon black-containing fiber (black dyed fiber) having a fineness of 2.5 denier was obtained by an ordinary wet spinning method. During spinning, a considerable amount of carbon black particles fell off in the coagulation bath and the drawing bath, causing problems such as black stains. This uniformly mixed black-dyed acrylic fiber was mixed in the same manner as in Example 5 to give a basis weight of 202 g / m ^2.
The knitted fabric was produced (Comparative Examples 5 to 8).

The evaluation results of the knitted fabric are shown in Table 2.

[0042]

[Table 2] As the results show, as the amount of carbon black particles in the fabric increases, the spectral heat absorption and heat retention property increases fairly proportionally until it is saturated, but the carbon black is not linearly oriented in the AN fiber, and It can be seen that there is no antistatic property just by uniformly dispersing.

(Example 6) The conductive fiber containing carbon black (7.2% carbon black product) obtained in Reference Example 1 was cut to 70 mm, and the anti-pill "Torelon" manufactured by Toray Industries, Inc.
T-2462 2d × 70mm and merino wool (quality 60 ′S) were mixed at a ratio of 5/65/30 to obtain a spun yarn with a metric count of 1/48 by ordinary worsted spinning. A knitted fabric was produced.

There is no problem with the hue of the knitted fabric. Spectral heat absorption and heat retention (spectral reflectance maximum value: 19%, cloth back temperature: 61.8).
℃), antistatic property (friction charging voltage: 0.8 KV, charge density:
2.0 μc / m ² ) is excellent, and the anti-pill property is 3 to
It was level 4.

(Examples 7 to 9 and Comparative Examples 9 to 11) The carbon black-containing conductive fiber (7.2% carbon black product) obtained in Reference Example 1 was cut into 76 mm, and Toray Co., Ltd. was used.
"Tetoron" T-901 3d x 89mm and merino wool (quality 60'S) 4/96 /
Three kinds of spun yarns having a metric count of 2/48 were obtained by ordinary worsted spinning by blending cotton in a ratio of 0, 4/66/30, 4/0/96. Further, as a comparison of these, spun yarns were obtained in the same manner for the above-mentioned "Tetoron 100%", "Tetoron 70% / wool, 100% wool" containing no conductive fiber.

These spun yarns were woven with a woven structure 2/1 twill,
Table 3 shows the results of evaluating the heat absorption and heat retention of the spectral heat absorption and the heat retention and antistatic property of each woven fabric after the fabric was dyed into black.

[0047]

[Table 3] As the results show, carbon black containing fiber
% Woven fabrics of Examples 7 to 9 had a spectral heat absorption and heat retention property,
Excellent results were obtained in terms of antistatic property.

[0048]

The knitted fabric of the present invention positively absorbs the near-infrared heat rays of sunlight, enhances the heat retaining property of the back face of the knitted fabric, and has an excellent antistatic effect in a low humidity environment. In addition, it has good pill resistance and does not have pills on knitted fabrics, and is also excellent in appearance, making it suitable for high-class winter clothing, sports, and leisure clothing in low-temperature and low-humidity environments.

Continuation of front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display location C09C 1/48 PBE D01F 6/54 B 7199-3B D02G 3/04 D04B 1/14 // D01F 8/08 A 7199-3B (72) Inventor Setsunori Kadota 3-3-3 Nakanoshima, Kita-ku, Osaka City Toray Co., Ltd.Osaka Plant (72) Inventor Nambae Kiyoyuki 1515 Tsutsui, Matsumae-cho, Iyo-gun, Ehime Toray Co., Ltd. Company Ehime factory

Claims (4)

[Claims] 1. A conductive fiber is mixed in an amount of 3 to 15% by weight, and the total amount of carbon black contained in the knitted fabric is 0.1% by weight.
The above is a knitted fabric having a frictional electrification voltage of 2 KV or less, wherein the conductive fibers have carbon black-containing antistatic polymers oriented in a streak pattern in single fibers, and the antistatic polymers are at least partially exposed on the fiber surface layer. Of the acrylic fiber, the electric resistivity of the conductive fiber is 10 to 10 ⁶ Ω · cm, and the wavelength of 760 mμ to 2000 mμ of the tubular knitted fabric having a basis weight of 200 g / m ² knitted from only the conductive fiber filament. A knitted fabric having a maximum spectral reflectance of 10% or less in a region. 2. The knitted fabric according to claim 1, wherein the maximum spectral reflectance in the wavelength region of 760 mμ to 2000 mμ is 40% or less. 3. The knitted fabric according to claim 1, wherein the anti-pill property is grade 3 or higher. 4. The knitted fabric according to claim 1, wherein the main fiber material is an acrylic fiber.