KR102299797B1 - Meta-Aramid Fiber improved dyeability and gloss, and Method for Preparing the Same - Google Patents

Abstract

The present invention relates to a meta-aramid fiber with improved dyeability and surface gloss, and a method for preparing the same comprising: a dope formation step for forming a meta-aramid dope by dissolving meta-aramid polymerized with M-phenylene diamine (MPD) and isophthaloyl chloride (IPC) in a polar amide solvent; a wet spinning step for spinning the dope in a coagulating solution containing 20-60 wt% of a polar amide-based solvent so as to form meta-aramid fibers; a wet stretching step for stretching the spun meta-aramid fibers in a coagulation solution containing 3-60 wt% of a polar amide-based solvent and adjusting the content of a polar amide solvent in the meta-aramid fibers to 3-9 wt%; a drying step for drying the meta-aramid fibers having a polar amide-based solvent content of 3-9 wt% at 150-300℃; a washing and drying step for washing and drying the dried meta-aramid fibers; and a heat treatment step for heat-treating the dried meta-aramid fibers.

Description

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

The present invention relates to a meta-aramid fiber having improved dyeability and glossiness and a method for manufacturing the same, and a meta-aramid fiber that improves the dyeability of the meta-aramid fiber by changing the fiber surface and improves the glossiness of the dyed meta-aramid fiber, and a method for producing the same is about

Aramid fiber is a synthetic fiber made from aromatic polymer that DuPont of the United States succeeded in developing in 1965 with the goal of fiber having the strength of glass fiber and heat resistance of asbestos. was produced with In 1974, the U.S. Federal Trade Commission defined the term aramid as a general name for “aromatic polyamides in which 85% or more of amide bonds are directly bonded by two aromatic rings”, and after that, ISO-2076, JIS L 0204-2 The name aramid was defined in the same way.

Aramid is divided into meta-type and para-type by the bonding unit of an amide-bonded aromatic ring. Meta-aramid fibers have excellent high-temperature heat resistance, and para-aramid fibers have high-strength and high elasticity as well as high-temperature heat resistance.

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 those of normal nylon, but it has very good heat stability, and is lighter than other heat-resistant materials and has the advantage of being comfortable because it can absorb sweat to some extent. have. Initially, only a few colors were limited, but recently, they are being made in various 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 clothes, and is used as a high-temperature filter for industrial purposes.

Although used in various fields as described above, meta-aramid fibers are often used with other fibers having excellent dyeability rather than being used alone due to poor dyeing performance. As in 2013-0133348, a pigment is added to the aramid polymer to prepare a raw yarn.

However, the meta-aramid fiber prepared from the raw yarn as described above has a problem in that a large amount of pigment is added for color expression, thereby reducing physical properties such as strength of the meta-aramid fiber.

In general, meta-aramid fibers are produced by wet stretching, which is drawn in a coagulating solution after wet spinning, and hot stretching after washing and drying. Therefore, there was a problem in that the dyeability was deteriorated due to the increase in the degree of crystallinity.

The present invention was invented to solve the problems of the prior art as described above, and an object of the present invention is to provide a meta-aramid fiber that improves dyeability by forming innumerable pores on the surface of the meta-aramid fiber.

Another object of the present invention is to provide a meta-aramid fiber with improved gloss through micropores and cross-sectional deformation formed in the meta-aramid fiber.

In addition, an object of the present invention is to provide a method for manufacturing a meta-aramid fiber with improved dyeability and gloss as described above.

In the present invention, meta-phenylene diamine (MPD) and meta-aramid polymerized with isophthaloyl chloride (IPC) are dissolved in a polar amide-based solvent to form meta-aramid dope dope formation step; a wet spinning step of spinning the dope in a coagulating solution containing 20 to 60 wt% of a polar amide-based solvent to form meta-aramid fibers; A wet stretching step of stretching the spun meta-aramid fiber in a coagulation solution containing 3 to 60 wt% of a polar amide-based solvent, and adjusting the remaining polar amide-based solvent content in the meta-aramid fiber to 3 to 9 wt%; A drying step of drying the meta-aramid fiber having a polar amide-based solvent content of 3 to 9 wt% at 150 to 300 °C; Washing and drying steps of washing and drying the dried meta-aramid fibers; It provides a method for producing meta-aramid fibers with improved dyeability and gloss, characterized in that it comprises a heat treatment step of heat-treating the dried meta-aramid fibers.

In addition, there is provided a method for producing meta-aramid fibers with improved dyeability and gloss, characterized in that the content of the polar amide-based solvent remaining in the meta-aramid fibers in the wet stretching step is adjusted to 4 to 7 wt%.

In addition, in the multi-stage stretching of the wet stretching step, the polar amide-based solvent contained in the coagulation solution of the last stretching is 3 to 9% by weight.

In addition, the drying step provides a method for producing meta-aramid fibers with improved dyeability and gloss, characterized in that the meta-aramid fibers are dried with a heating roller.

In addition, the temperature of the drying step provides a method for producing meta-aramid fibers with improved dyeability and gloss, characterized in that 10 ~ 30 ℃ higher than the boiling point of the polar amide-based solvent used.

In addition, there is provided a meta-aramid fiber with improved dyeability and glossiness, characterized in that it is produced by the method for producing the meta-aramid fiber.

In addition, the dyeing concentration (K / S) of the meta-aramid fiber provides a meta-aramid fiber with improved dyeability and gloss, characterized in that 10 or more.

As described above, the meta-aramid fiber capable of improving dyeability according to the present invention vaporizes the polar amide-based solvent remaining inside the meta-aramid fiber at a high temperature, and as the vaporized polar amide-based solvent is discharged to the outside of the fiber, it is applied to the fiber surface. It has the effect of improving the dyeability by forming micropores.

In addition, the meta-aramid fiber of the present invention has the effect of improving gloss through a number of micropores and cross-sectional deformation formed on the fiber surface.

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

Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. First, it should be noted that in the drawings, the same components or parts are denoted by the same reference numerals whenever possible. In describing the present invention, detailed descriptions of related known functions or configurations are omitted so as not to obscure the gist of the present invention.

As used herein, the terms 'about', 'substantially' and the like are used in or close to the numerical value when manufacturing and material tolerances inherent in the stated meaning are presented, and provide an understanding of the present invention. To help, precise or absolute figures are used to prevent unfair use by unscrupulous infringers of the stated disclosure.

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

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

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

In the present invention, a polymerization process for preparing meta-aramid by polymerizing meta-phenylene diamine (MPD) and isophthaloyl chloride (IPC), and the polymerized meta-aramid in a polar amide solvent A meta-aramid dope can be formed by a solvent mixing process of dissolving 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. . The meta-aramid dope preferably contains 10 to 40% by weight of meta-aramid in the polar amide-based solvent, more preferably 10 to 25% by weight of meta-aramid.

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

The wet spinning step is a step of spinning the dope in a coagulation solution containing a polar amide-based solvent including an amide-based solvent to form meta-aramid fibers.

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

In the wet stretching step, the spun meta-aramid fiber is drawn in a coagulation solution containing 3 to 60 wt% of a polar amide-based solvent, and the remaining polar amide-based solvent in the meta-aramid fiber is adjusted to 3 to 9 wt%. is a step

When the content of the remaining polar amide solvent in the meta-aramid fiber is less than 3% by weight, the effect of improving dyeability and glossiness may be insignificant. When the content of the polar amide-based solvent exceeds 9% by weight, fusion between the fibers occurs in the drying step. Since fairness may be reduced, the content of the remaining polar amide-based solvent in the meta-aramid fiber is preferably 3 to 9% by weight, and more preferably 4 to 7% by weight of the polar amide-based solvent.

The content of the polar amide-based solvent remaining in the meta-aramid fiber can be controlled by the content of the polar amide-based solvent in the coagulation solution of the wet-stretching coagulation bath.

In the wet stretching step, stretching is preferably performed in multiple stages, and each stretching process can be performed in a coagulating solution having a different polar amide solvent content. In the coagulating solution, the polar amide-based solvent may be adjusted to 3 to 9% by weight, thereby controlling the content of the remaining polar amide-based solvent in the meta-aramid fiber to 3 to 9% by weight.

The drying step is a step of forming micropores on the surface of the meta-aramid fiber, and the meta-aramid fiber having a polar amide-based solvent content of 3 to 9 wt% is dried at 150 to 300°C.

As described above, the meta-aramid fibers containing the polar amide-based solvent at high temperature are discharged to the outside while the polar amide-based solvent is vaporized during drying to form pores on the surface of the meta-aramid fibers.

Figure 2 (a) is a cross-section of the meta-aramid fiber after the wet drawing step, Figure 2 (b) is a cross-section of the meta-aramid fiber after the drying step. And, it can be seen that the fiber of FIG. 2(b) has a rough surface and many deformations are formed in a circular cross section, and it can be seen that micropores are formed in the drying step and the cross section of the fiber is deformed.

In the drying step, it is preferable to dry the meta-aramid fibers by using a heating roller. Direct heat is applied to the meta-aramid fibers to promote vaporization of the polar amide-based solvent, thereby shortening the process time.

The drying step can be adjusted according to the content of the polar amide-based solvent remaining in the meta-aramid fibers, and is preferably carried out for about 15 to 120 seconds.

In addition, the temperature of the drying step can be adjusted according to the polar amide-based solvent used, and preferably 10 to 30° C. higher than the boiling point of the polar amide-based solvent used.

That is, dimethyl acetamide (DMAc) has a boiling point of about 165°C, N-methylpyrrolidone (NMP) has a boiling point of about 202°C, and dimethyl formamide (DMF) has a boiling point of about 165°C. This about 153 ℃, dimethyl imidazolidinone (Dimethyl imidazolidinone) has a boiling point of about 225 ℃, and when using dimethylacetamide (DMAc) as a polar amide solvent, the drying step is preferably carried out at a temperature of 175 ~ 195 ℃ something to do.

In the washing and drying step, the water contained in the meta-aramid fiber from which the polar amide solvent is removed through water washing and water washing of the fibrous meta-aramid fiber to remove the polar amide-based solvent not removed in the drying step This is a drying step to remove.

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

The heat treatment step is a step to improve the orientation of the meta-aramid fibers by heat-treating the dried meta-aramid fibers at a high temperature of 250 to 450 °C. can do.

After the heat treatment step, the crimping step and the like may be additionally performed, and may be performed in the same manner as the general method of manufacturing meta-aramid fibers.

The meta-aramid fiber produced by the method for producing meta-aramid fibers with improved dyeability and gloss of the present invention as described above has improved dyeability and glossiness due to micropores and cross-sectional shape modification. The dyeing concentration (K/S) of meta-aramid fibers is 10 or more, and the dyeability will be excellent.

Hereinafter, examples of a method for manufacturing a meta-aramid fiber with improved dyeability and gloss according to the present invention are shown, but these examples are only presented to understand the content of the present invention, and the scope of the present invention is limited to these examples should not be construed as necessarily limited to

Examples 1 to 9

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

The meta-aramid dope (Dope) was wet-spun in a coagulation bath of 50% by weight of DMAc and a coagulation solution at 50° C. to prepare meta-aramid fibers.

The spun meta-aramid fiber was stretched in one stage at 30% by weight of DMAc, 50 ℃ coagulating solution, 20% by weight of DMAc, in 2 stages at 50 ℃ coagulating solution, and three-stage stretching at 50 ℃ coagulating solution with the DMAc content of Table 1 below. After wet drawing, a meta-aramid fiber having a DMAc content adjusted to 2 to 10 wt% was obtained.

The meta-aramid fiber in which DMAc remains was dried for 30 seconds through a heating roller at 180° C., then washed with water and dried. Figure 2 (a) is a cross-sectional photograph of the fiber after wet drawing of Example 6, Figure 2 (b) is a photograph of the cross-section of the fiber after the drying step of Example 6.

The dried meta-aramid fibers were hot-drawn at 250-350° C., and heat-treated at 300-450° C. to prepare meta-aramid fibers with improved dyeability according to the present invention.

◈ Dyeability and gloss evaluation

The meta-aramid fibers of Examples 1 to 9 were dyed with a violet dye (dye concentration 1%, dyeing temperature 130° C.), which is a mixture of blue and red of M dohmen Korea, and then glossiness, dye concentration and fiber fusion were measured. 1 is shown.

* How to measure

○ Gloss (Gloss Meter): 60℃ value was measured by ASTM D523 method (LANDEK, GM-268)

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

K/S = (1-R) ² ÷ (2R)

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

○ Fiber fusion: Visually observe fusion between fibers in a fiber bundle of 500 strands and determine the frequency of fusion (X: no fusion, ○: 1 to 10 fused yarns, ◎: 10 or more fused yarns)

division DMAc content
(weight%) glossiness
(gloss meter) fiber fusion K/S Example 1 2 0.21 X 13.2 Example 2 3 0.32 X 13.8 Example 3 4 0.41 X 14.1 Example 4 5 0.43 X 14.5 Example 5 6 0.51 X 15.5 Example 6 7 0.62 X 18.8 Example 7 8 0.65 ○ 19.8 Example 8 9 0.72 ○ 20.1 Example 9 10 0.75 ◎ 20.3

As shown in Table 1, the higher the content of the polar amide solvent remaining in the meta-aramid fiber, the greater the micropores and fiber cross-section deformation, thereby improving gloss and dyeing concentration. it can be seen that

When the content of the polar amide-based solvent remaining in the meta-aramid fiber is 2% by weight, the gloss is low, so it may be preferable that the content of the remaining polar amide-based solvent is 3% by weight or more.

In addition, when the content of the polar amide-based solvent remaining in the meta-aramid fiber is 4 to 7% by weight, the gloss and dyeing concentration are excellent, and the fiber fusion is low, when the content of the remaining polar amide-based solvent is 4 to 7% by weight would be most preferable.

Claims (7)

Dope forming step of dissolving meta-aramid polymerized with meta-phenylene diamine (MPD) and isophthaloyl chloride (IPC) in a polar amide-based solvent to form meta-aramid dope;
a wet spinning step of spinning the dope in a coagulating solution containing 20 to 60 wt% of a polar amide-based solvent to form meta-aramid fibers;
A wet stretching step of stretching the spun meta-aramid fiber in a coagulation solution containing 3 to 60 wt% of a polar amide-based solvent, and adjusting the remaining polar amide-based solvent content in the meta-aramid fiber to 3 to 9 wt%;
A drying step of drying the meta-aramid fiber having a polar amide-based solvent content of 3 to 9 wt% at 150 to 300 °C;
Washing and drying steps of washing and drying the dried meta-aramid fibers;
Method for producing meta-aramid fibers with improved dyeability and gloss, characterized in that it comprises a heat treatment step of heat-treating the dried meta-aramid fibers. According to claim 1,
Method for producing meta-aramid fibers with improved dyeability and gloss, characterized in that the content of the polar amide-based solvent remaining in the meta-aramid fibers in the wet stretching step is adjusted to 4 to 7% by weight. According to claim 1,
Method for producing meta-aramid fibers with improved dyeability and gloss, characterized in that the polar amide-based solvent contained in the coagulation solution of the last stretching in the multi-stage stretching of the wet stretching step is 3 to 9% by weight. According to claim 1,
The drying step is a method for producing meta-aramid fibers with improved dyeability and gloss, characterized in that the meta-aramid fibers are dried with a heating roller. According to claim 1,
The temperature of the drying step is a method for producing meta-aramid fibers with improved dyeability and gloss, characterized in that 10 ~ 30 ℃ higher than the boiling point of the polar amide-based solvent used. [Claim 6] Meta-aramid fiber with improved dyeability and gloss, characterized in that it is prepared by the method for producing the meta-aramid fiber of any one of claims 1 to 5. 7. The method of claim 6,
The dyeing concentration (K / S) of the meta-aramid fiber is improved dyeability and gloss, characterized in that 10 or more meta-aramid fiber.

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