KR102586540B1 - Meta-Aramid Fiber improved dyeability and gloss, and Method for Preparing the Same - Google Patents

Abstract

The present invention is a dope formation in which meta-aramid polymerized with meta-phenylene diamine (MPD) and isophthaloyl chloride (IPC) is dissolved in a polar amide-based solvent to form meta-aramid dope. step; A wet spinning step of spinning the dope in a coagulating solution containing a polar amide-based solvent to form meta-aramid fiber; A wet stretching step of stretching the spun meta-aramid fibers in three or more stages in a coagulating solution containing a polar amide-based solvent; A washing and drying step of washing and drying the wet stretched meta-aramid fiber; A meta-aramid fiber with improved dyeability and gloss, comprising a hot stretching step of hot stretching the dried meta-aramid fiber at a high temperature, wherein the wet stretching ratio of the wet stretching step is greater than the hot stretching ratio of the hot stretching step, and production thereof It's about method.

Description

Meta-Aramid Fiber improved dyeability and gloss, and Method for Preparing the Same}

The present invention relates to a meta-aramid fiber with improved dyeability and glossiness and a method for manufacturing the same. A meta-aramid fiber and a method for manufacturing the same improve the dyeability of the meta-aramid fiber by changing the fiber surface and improve the glossiness of the dyed meta-aramid fiber. It's about.

Aramid fiber is a synthetic fiber made from aromatic polymers that was successfully developed in 1965 by the American company Dupont with the goal of producing a fiber with the strength of glass fiber and the heat resistance of asbestos. It was branded as Kevlar in the late 1960s. was produced with In 1974, the U.S. Federal Trade Commission defined the term aramid as a general name for “aromatic polyamide in which more than 85% of the amide bonds are directly bonded to two aromatic rings.” Afterwards, it was also used in ISO-2076 and JIS L 0204-2. The name aramid was defined identically.

Aramids are divided into meta and para groups based on the bonding unit of the amide-bonded aromatic ring. Meta-aramid fibers have excellent high-temperature heat resistance, and para-aramid fibers have the characteristics of high-temperature heat resistance as well as high strength and high elasticity.

Representative examples of the meta-aramid include Nomex developed by DuPont and Conex developed by Teijin. Meta-aramid is a benzene ring bonded to an amide group at the meta position. Its strength and elongation are similar to ordinary nylon, but it has excellent heat stability. It is lighter than other heat-resistant materials and can absorb sweat to a certain extent, so it has the advantage of being comfortable. there is. Initially, colors were limited to a few colors, but recently they are being made in a variety of colors, including fluorescent colors. It is used as a material for heat-resistant clothing such as firefighting suits, uniforms for racing car drivers, astronaut uniforms, and work uniforms, and is used as a high-temperature filter for industrial purposes.

Although it is used in various fields as described above, meta-aramid fibers have poor dyeing performance and are often used together with other fibers with excellent dyeing properties rather than being used alone. In order to impart color, they are used in Korea Patent No. 1551432 and Published Patent No. As in 2013-0133348, pigment is added to aramid polymer to produce dope-dyed yarn.

However, the meta-aramid fiber manufactured from the above-mentioned dope-dyed yarn had a problem in that a large amount of pigment was added to express the color, thereby lowering the physical properties such as the strength of the meta-aramid fiber.

In general, meta-aramid fibers are manufactured by wet stretching in a coagulating liquid after wet spinning, and then hot stretching after washing and drying. The orientation of general meta-aramid fibers is greatly increased by increasing the draw ratio of hot stretching compared to wet stretching during manufacturing. Therefore, there was a problem of poor dyeing properties due to increased crystallinity.

The present invention was invented to solve the problems of the prior art as described above, and is a meta-aramid that improves the dyeability and gloss of the meta-aramid fiber by changing the cross-section and surface structure of the meta-aramid fiber by stretching from the wet stretching step to multi-step stretching. The purpose is to provide fiber.

In addition, the purpose is to provide a manufacturing method for manufacturing meta-aramid fibers with improved dyeability and glossiness as described above.

The present invention is a dope formation in which meta-aramid polymerized with meta-phenylene diamine (MPD) and isophthaloyl chloride (IPC) is dissolved in a polar amide-based solvent to form meta-aramid dope. step; A wet spinning step of spinning the dope in a coagulating solution containing a polar amide-based solvent to form meta-aramid fiber; A wet stretching step of stretching the spun meta-aramid fibers in three or more stages in a coagulating solution containing a polar amide-based solvent; A washing and drying step of washing and drying the wet stretched meta-aramid fiber; A method for producing meta-aramid fibers with improved dyeability and gloss, comprising a hot stretching step of hot stretching dried meta-aramid fibers at a high temperature, wherein the wet stretching ratio of the wet stretching step is greater than the hot stretching ratio of the hot stretching step. to provide.

In addition, it provides a method for manufacturing meta-aramid fibers with improved dyeability and gloss, characterized in that the wet draw ratio in the wet stretching step is 2.0 to 4.0.

In addition, it provides a method for producing meta-aramid fibers with improved dyeability and gloss, characterized in that the hot draw ratio in the hot stretching step is 1.1 to 1.9.

In addition, the wet stretching step provides a method for producing meta-aramid fibers with improved dyeability and gloss, characterized in that wet stretching is performed in 3 to 4 stages of multi-stage stretching.

In addition, the meta-aramid fiber with improved dyeability and gloss is characterized in that it satisfies the following equation when the wet draw ratio of the wet stretching step is dw, the hot draw ratio of the hot stretching step is dh, and the number of stages in the wet stretching step is nb. Manufacturing method is provided.

Equation (dw/dh)*nb≥5.5

In addition, it provides a meta-aramid fiber with improved dyeability and glossiness, which is manufactured by the above-mentioned meta-aramid fiber manufacturing method.

In addition, the meta-aramid fiber provides a meta-aramid fiber with improved dyeability and gloss, characterized in that the dyeing concentration (K/S) of the meta-aramid fiber is 20 or more.

The meta-aramid fiber with improved dyeability and gloss according to the present invention as described above has the effect of improving the dyeability and gloss of the meta-aramid fiber by changing the cross-section and surface structure of the meta-aramid fiber by stretching in multi-stage stretching in the wet stretching stage. there is.

Figure 1 is a diagram showing a process diagram of a method for manufacturing meta-aramid fiber with improved dyeability and glossiness according to the present invention.

Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the drawings attached to the present invention. First of all, it should be noted that among the drawings, identical components or parts are indicated by the same reference numerals whenever possible. In describing the present invention, detailed descriptions of related well-known functions or configurations are omitted in order to not obscure the gist of the present invention.

As used herein, the terms 'about', 'substantially', etc. are used to mean at or close to the numerical value when manufacturing and material tolerances inherent in the stated meaning are presented, and are used to enhance the understanding of the present invention. Precise or absolute figures are used to assist in preventing unscrupulous infringers from taking unfair advantage of stated disclosures.

Figure 1 is a diagram showing a process diagram of a method for manufacturing a meta-aramid fiber with improved dyeability and glossiness according to the present invention, and Figure 2 is a photograph showing a cross-sectional view of a meta-aramid fiber with improved dyeability and glossiness according to the present invention.

The present invention relates to a method for producing meta-aramid fibers with improved dyeability and gloss, including a dope forming step, wet spinning step, wet stretching step, water washing/drying step, and hot stretching step, as shown in Figure 1.

The dope formation step is a step of forming meta-aramid dope by dissolving meta-aramid polymerized with meta-phenylene diamine (M-phenylene diamine (MPD)) and isophthaloyl chloride (IPC) in a solvent.

In the present invention, a polymerization process for producing meta-aramid by polymerizing meta-phenylene diamine (M-phenylene diamine (MPD)) and isophthaloyl chloride (IPC), and the polymerized meta-aramid in a polar amide-based solvent. Meta-aramid dope can be formed through a solvent mixing process of melting and mixing.

When forming the meta-aramid dope, the viscosity of the meta-aramid dope can be adjusted according to the mixing ratio of the polar amide-based solvent and meta-aramid. It would be desirable to adjust the mixing ratio of the polar amide-based solvent and meta-aramid to be suitable for spinning. . The meta-aramid dope preferably contains 10 to 40% by weight of meta-aramid in the polar amide-based solvent, and more preferably contains 10 to 25% by weight of meta-aramid.

The polar amide-based solvent includes dimethyl acetamide (DMAc), N-methylpyrrolidone (NMP), dimethyl formamide (DMF), and dimethyl imidazolidinone. Any one compound can be used, and it is preferable to use dimethylacetamide, which is most effective.

The wet spinning step is a step of turning the dope into meta-aramid fiber by spinning it in a coagulating solution containing a polar amide-based solvent.

The coagulating liquid is a mixture of a polar amide-based solvent and water, and the polar amide-based solvent is dimethyl acetamide (DMAc), N-methylpyrrolidone (NMP), and dimethyl formamide (DMF). , Dimethyl imidazolidinone can be used, and in the present invention, it is preferable to use dimethylacetamide, and the dimethylacetamide (DMAc) is 3 to 60% by weight, and water is 40 to 80% by weight. It would be preferable to use a mixture of weight percent.

The wet stretching step is a step of stretching the spun meta-aramid fiber in a coagulating solution containing 3 to 60% by weight of a polar amide-based solvent.

In the wet stretching step of the present invention, the spun meta-aramid fiber is stretched in three or more stages in a coagulating liquid.

The wet stretch ratio in the wet stretching step is preferably 2.0 to 4.0. If the wet stretch ratio is low or too high, dyeability and gloss may be reduced, so it is most preferably 2.5 to 3.5.

The wet stretching step is a multi-step stretching, and it is desirable that each stretching process can be performed in a coagulating liquid with a different polar amide solvent content. As the number of wet stretching increases, the stretching is performed in a coagulating liquid with a lower polar amide solvent content. It would be desirable to do so.

The washing and drying step is a step of washing the fiberized meta-aramid fibers to remove the polar amide-based solvent and drying to remove moisture contained in the meta-aramid fibers from which the polar amide-based solvent was removed through water washing. .

The washing and drying steps may be performed in the same manner as for meta-arimid fiber through general wet spinning.

The hot stretching step is a step of improving the orientation of the meta-aramid fibers by hot stretching the dried meta-aramid fibers at a high temperature of 250 to 450 ° C. The meta-aramid fibers can be hot stretched through a hot stretching roller.

It is preferable that the hot stretch ratio of the hot stretching step is 1.1 to 1.9. It is preferable that the wet stretch ratio of the wet stretching step is larger than the hot stretch ratio of the hot stretching step, and the hot stretch ratio of the hot stretching step is more preferably 1.3 to 1.8. It would be desirable.

Meta-aramid fibers with improved dyeability and glossiness as described above have a wet draw ratio in the wet stretching stage that is greater than the hot draw ratio in the hot stretching stage, thereby changing the cross-section and surface structure of the meta-aramid fibers, thereby improving the dyeability and glossiness of the meta-aramid fibers. do.

When the wet stretch ratio in the wet stretching step is dw, the hot stretch ratio in the hot stretching step is dh, and the number of stages in the wet stretching step is nb, it is preferable to satisfy the following equation.

Equation (dw/dh)*nb≥5.5

If the above formula is satisfied, the dyeing concentration (K/S) of the meta-aramid fiber is 20 or more, resulting in very excellent dyeing properties.

After the heat treatment step, the crimp application step can be additionally performed, and can be performed in the same manner as the general method of manufacturing meta-aramid fiber.

The meta-aramid fiber produced by the method for producing meta-aramid fiber with improved dyeability and gloss of the present invention as described above is a meta-aramid fiber whose dyeability and gloss are improved by controlling the wet draw ratio in the wet stretching step by controlling the hot draw ratio in the hot stretching step. The dyeing concentration (K/S) of the fiber will be 20 or higher, providing excellent dyeing properties.

Hereinafter, examples of a method for producing meta-aramid fibers with improved dyeability and glossiness according to the present invention are shown, but these examples are provided only to understand the content of the present invention and the scope of the present invention is limited to these examples. It should not be construed as necessarily limited to.

Examples 1 to 3

Meta-aramid polymerized with meta-phenylene diamine (MPD) and isophthaloyl chloride (IPC) is dissolved in the solvent dimethylacetamide (DMAc) to produce meta-aramid with a meta-aramid concentration of 20% by weight. Dope was formed.

The meta-aramid dope was wet-spun in a coagulation tank containing 50% by weight of DMAc and a coagulating solution at 50°C to prepare meta-aramid fiber.

The spun meta-aramid fiber was wet stretched in 1st stage with 30% by weight of DMAc and 50℃ coagulation solution, 2nd stage stretching with 20% by weight of DMAc in 50℃ coagulation solution, and 3rd stage stretching with 10% by weight of DMAc in 50℃ coagulation solution. It was washed with water and dried.

The dried meta-aramid fiber was hot-stretched at 300-400°C to prepare a meta-aramid fiber with improved dyeability according to the present invention.

The wet draw ratio and hot draw ratio according to each example are shown in Table 1.

Examples 4 to 6

It was manufactured under the same conditions as in Example 1, but after three stages of wet stretching, it was wet stretched in four stages in a coagulant containing 5% by weight of DMAc at 50°C, followed by washing and drying.

The wet draw ratio and hot draw ratio according to each example are shown in Table 1.

Comparative Examples 1 to 3

It was manufactured under the same conditions as Example 1, but the spun meta-aramid fiber was wet stretched in one stage in a coagulating solution containing 30% by weight of DMAc and 50°C, and in two stages in a coagulating solution containing 13% by weight of DMAc at 50°C, and then washed with water and It was dried.

The wet stretching ratio and hot stretching ratio according to each comparative example are shown in Table 1.

◈ Dyeing and gloss evaluation

After dyeing the meta-aramid fibers prepared in Examples 1 to 6 and Comparative Examples 1 to 3 with violet dye (dye concentration 1%, dyeing temperature 130°C), a mixture of blue and red from M dohmen Korea, glossiness and dyeing Concentration, Kd value, strength, and elongation were measured and shown in Table 1.

* measurement method

○ Gloss Meter: Measured at 60℃ using ASTM D523 method (LANDEK, GM-268)

○ Dyeing concentration (K/S): Using a colorimeter (GretagMacbeth Color-Eye 7000A), measure the surface reflectance at the maximum absorption wavelength of the dyed fabric and calculate the dyeing concentration (K/S) according to the Kubelka-Munk equation for each condition. Compare the dyeing concentration of dyed fabrics according to.

K/S = (1-R) ² ÷(2R)

(Here, K is the extinction coefficient, S is the scattering coefficient, and R is the reflectance)

○ Kd value = (dw/dh)*nb

○ Strength and elongation: Measured using the test method of ASTM D 3822.

division Example
One Example
2 Example
3 Example
4 Example
5 Example
6 Comparative example
One Comparative example
2 Comparative example
3 Number of wet stretching stages (nb) 3 3 3 4 4 4 2 2 2 Wet draw ratio (dw) 2.5 3 3.5 2.5 3 3.5 2.5 3 3.5 Hot rolling mystery (dh) 1.8 1.5 1.3 1.8 1.5 1.3 1.8 1.5 1.3 Kd value 4.2 6 8.2 5.6 8 10.9 2.8 4 5.4 Strength (g/de) 5.7 5.4 5.2 5.8 5.6 5.4 5.5 5.2 5.1 Elasticity (%) 40 42 45 40 42 44 41 43 45 Glossiness 0.57 0.58 0.62 0.66 0.68 0.72 0.48 0.51 0.55 K/S 19.8 20.1 20.2 20.2 20.3 20.5 18.5 18.7 19.1

As shown in Table 1, there is no significant difference in strength and elongation between Examples 1 to 6 and Comparative Examples 1 to 3, but Examples 1 to 6, which were wet stretched in three or more stages in the wet stretching step, have better dyeability and gloss than the Comparative Examples. It can be seen that it is excellent.

In addition, when the Kd value is 5.5 or higher, the dyeing concentration (K/S) is 20 or higher and the gloss is excellent. When manufactured with a Kd value of 5.5 or higher, meta-aramid fibers with excellent dyeability and gloss can be manufactured. You will be able to.

Claims (7)

A dope formation step in which meta-aramid polymerized with M-phenylene diamine (MPD) and isophthaloyl chloride (IPC) is dissolved in a polar amide-based solvent to form meta-aramid dope;
A wet spinning step of spinning the dope in a coagulating solution containing a polar amide-based solvent to form meta-aramid fiber;
A wet stretching step of stretching the spun meta-aramid fibers in 3 to 4 stages in a coagulating solution containing a polar amide-based solvent;
A washing and drying step of washing and drying the wet-stretched meta-aramid fiber;
Including a hot stretching step of hot stretching the dried meta-aramid fiber at a high temperature,
The wet stretch ratio in the wet stretching step is greater than the hot stretching ratio in the hot stretching step,
In the wet stretching step, as the number of wet stretching increases, stretching is performed in a coagulating solution with a lower content of polar amide solvent,
A method for manufacturing meta-aramid fiber with improved dyeability and gloss, characterized in that it satisfies the following equation when the wet stretch ratio of the wet stretching step is dw, the hot stretch ratio of the hot stretching step is dh, and the number of stages in the wet stretching step is nb. .
Equation (dw/dh)*nb≥5.5 According to paragraph 1,
A method for producing meta-aramid fibers with improved dyeability and gloss, characterized in that the wet draw ratio in the wet stretching step is 2.0 to 4.0. According to paragraph 1,
A method for producing meta-aramid fibers with improved dyeability and gloss, characterized in that the hot draw ratio in the hot stretching step is 1.1 to 1.9. delete delete A meta-aramid fiber with improved dyeability and gloss, characterized in that it is manufactured by the meta-aramid fiber production method of any one of claims 1 to 3. According to clause 6,
A meta-aramid fiber with improved dyeability and gloss, characterized in that the dyeing concentration (K/S) of the meta-aramid fiber is 20 or more.

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