KR20220163100A - 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. The method comprises: a dope formation step of 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 of spinning the dope in a coagulating solution containing a polar amide-based solvent so as to form meta-aramid fibers; a wet stretching step of stretching the spun meta-aramid fibers in a coagulation solution containing the polar amide-based solvent, wherein the stretching is performed in a multi-stage type of three stages or more; a wet washing and drying step of wet washing and drying the wet-stretched meta-aramid fibers; and a heat stretching step of thermally stretching the dried meta-aramid fibers at high temperature, wherein a wet stretching ratio in the wet stretching step is greater than a heat stretching ratio in the heat stretching step.

Description

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

The present invention relates to meta-aramid fibers with improved dyeability and glossiness and a method for manufacturing the same, and to meta-aramid fibers that change the fiber surface to improve the dyeability of meta-aramid fibers and the glossiness of dyed meta-aramid fibers, and a method for manufacturing the same It is about.

Aramid fiber is a synthetic fiber made from an aromatic polymer that was successfully developed in 1965 by DuPont of the United States with the goal of producing a fiber with the strength of glass fiber and the 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 with two aromatic rings”. The name aramid was defined identically.

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

The meta-aramid is representative of 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 excellent heat stability, is lighter than other heat-resistant materials, and can absorb sweat to some extent, so it has the advantage of being comfortable. have. In the early days, colors were limited to a few, 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 uniforms, uniforms for race car drivers, uniforms for astronauts, and working clothes, and for industrial purposes, it is used as a high-temperature filter.

Although used in various fields as described above, meta-aramid fibers are often used together with other fibers having excellent dyeability rather than being used alone due to poor dyeing performance. As in No. 2013-0133348, a dye is added to an aramid polymer to produce a dyed yarn.

However, the meta-aramid fiber prepared with the dope-dyed 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 in a coagulating solution after wet spinning, followed by washing and drying, followed by hot-stretching. General meta-aramid fibers increase the draw ratio of hot-stretching compared to wet-stretching during manufacture, greatly increasing the degree of orientation. Therefore, there is a problem in that dyeability is deteriorated due to an increase in crystallinity.

The present invention was invented to solve the problems of the prior art as described above, and the cross-section and surface structure of meta-aramid fibers are changed by stretching in multi-step drawing in the wet drawing step, thereby improving the dyeability and glossiness of meta-aramid fibers Meta-aramid It aims to provide fibers.

In addition, it is an object of the present invention to provide a manufacturing method for producing meta-aramid fibers having improved dyeability and glossiness.

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

In addition, the wet stretching ratio in the wet stretching step provides a method for producing meta aramid fibers with improved dyeability and glossiness, characterized in that 2.0 to 4.0.

In addition, it provides a method for producing meta-aramid fiber with improved dyeability and glossiness, 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 glossiness, characterized in that wet stretching in 3 to 4 stages of multi-stage stretching.

In addition, when the wet stretching ratio of the wet stretching step is dw, the hot stretching ratio of the hot stretching step is dh, and the multi-stage number of the wet stretching step is nb, the following formula is satisfied Meta aramid fiber with improved dyeability and glossiness A manufacturing method is provided.

Formula (dw/dh)*nb≥5.5

In addition, it provides a meta-aramid fiber with improved dyeability and glossiness, characterized in that produced by the above meta-aramid fiber manufacturing method.

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

Meta aramid fibers with improved dyeability and glossiness according to the present invention as described above are stretched in multi-step drawing in the wet drawing step to change the cross-section and surface structure of meta aramid fibers, thereby improving the dyeability and glossiness of meta aramid fibers. have.

1 is a diagram showing a process chart of a method for manufacturing meta-aramid fibers 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 accompanying drawings. First of all, it should be noted that in the drawings, the same components or parts are denoted by the same reference numerals as much as possible. In describing the present invention, detailed descriptions of related known functions or configurations are omitted in order not to obscure the gist of the present invention.

As used herein, the terms 'about', 'substantially', and the like are used in a sense at or approximating that number when manufacturing and material tolerances inherent in the stated meaning are given, and are intended to convey an understanding of the present invention. Accurate or absolute figures are used to help prevent exploitation by unscrupulous infringers of the disclosed disclosure.

Figure 1 is a view showing a process diagram of a meta-aramid fiber manufacturing method with improved dyeability and glossiness according to the present invention, Figure 2 is a photograph showing a cross-sectional view of 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 glossiness, including a dope forming step, a wet spinning step, a wet drawing step, a water washing/drying step, and a hot drawing step, as shown in FIG.

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

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-based solvent Meta-aramid dope can be formed by 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, and it is preferable 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, more preferably 10 to 25% by weight of meta-aramid.

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

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

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

The wet stretching step is a step of stretching the meta-aramid fibers to be spun 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 fibers are stretched in three or more multi-stage stretching in a coagulating solution.

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

The wet stretching step is multi-stage stretching, and it is preferable that each stretching process can be performed in a coagulating solution having a different polar amide-based solvent content. It would be preferable to

The water washing and drying step is a step of washing the fiberized meta-aramid fibers with water 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 has been removed through water washing. .

The water washing and drying step may be performed in the same way as meta arimide fibers 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., and the meta aramid fibers can be hot stretched through a hot drawing roller.

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

As described above, the meta aramid fiber with improved dyeability and glossiness has a higher wet draw ratio in the wet drawing step than the hot draw ratio in the hot drawing step, thereby changing the cross-section and surface structure of the meta aramid fiber, thereby improving the dyeability and glossiness of the meta aramid fiber do.

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

Formula (dw/dh)*nb≥5.5

When the above formula is satisfied, the dyeing concentration (K / S) of the meta-aramid fiber is 20 or more and has very good dyeability.

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

The meta-aramid fiber produced by the meta-aramid fiber manufacturing method with improved dyeability and glossiness of the present invention as described above has improved dyeability and glossiness by adjusting the wet-stretch ratio in the wet-stretching step and the hot-stretch ratio in the hot-stretching step. Meta-aramid The dyeing concentration (K/S) of the fiber will be excellent at 20 or more.

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 only presented to understand the contents of the present invention, and the scope of the present invention does not extend to these examples. should not be construed as necessarily limited to

Examples 1 to 3

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

Meta-aramid fibers were prepared by wet-spinning the meta-aramid dope in a coagulation bath of 50% by weight of DMAc and a 50° C. coagulation solution.

The spun meta-aramid fiber was DMAc 30% by weight, 50 ℃ coagulation liquid in one step stretching, DMAc 20% by weight, 50 ℃ coagulation solution in two stages, DMAc 10% by weight, wet stretching in 50 ℃ coagulation solution in three stages. It was washed with water and dried.

The dried meta-aramid fibers were heat-stretched at 300 to 400° C. to prepare meta-aramid fibers with improved dyeability according to the present invention.

The wet stretching ratio and the hot stretching ratio according to each Example are shown in Table 1.

Examples 4 to 6

It was prepared under the same conditions as in Example 1, but after three-stage stretching in the wet stretching step, it was washed with water and dried after four-stage wet stretching in DMAc 5% by weight and a 50 ° C. coagulant solution.

The wet stretching ratio and the hot stretching ratio according to each Example are shown in Table 1.

Comparative Examples 1 to 3

It was prepared under the same conditions as in Example 1, but the spun meta-aramid fibers were wet-stretched by single-stage stretching in DMAc 30% by weight and 50 ° C. coagulating solution, and two-stage stretching in DMAc 13% by weight and 50 ° C. coagulating solution, washed with water and dried.

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

◈ Evaluation of dyeability and glossiness

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), which is a mixture of blue and red of M dohmen Korea, glossiness, dyeing Concentration, Kd value, and strength and elongation were measured and shown in Table 1.

* How to measure

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

○ Dyeing concentration (K/S): Using a colorimeter (GretagMacbeth Color-Eye 7000A), the surface reflectance is measured at the maximum absorption wavelength of the dyed fabric, and the dyeing concentration (K/S) is calculated 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)

○ Kd value = (dw/dh)*nb

○ Strength and elongation: Measured according to 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 stages of wet stretching (nb) 3 3 3 4 4 4 2 2 2 Practice Mystery (dw) 2.5 3 3.5 2.5 3 3.5 2.5 3 3.5 Hot rolling ratio (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 Intensity (g/de) 5.7 5.4 5.2 5.8 5.6 5.4 5.5 5.2 5.1 Confidence (%) 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, Examples 1 to 6 and Comparative Examples 1 to 3 did not have a significant difference in strength and elongation, but Examples 1 to 6 wet-stretched in three stages or more in the wet-stretching step had higher dyeability and gloss than Comparative Examples. It can be seen that is excellent.

In addition, when the Kd value is 5.5 or more, it can be seen that the dye concentration (K / S) is 20 or more and the glossiness is excellent. You will be able to.

Claims (7)

A 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 a polar amide-based solvent to make meta-aramid fibers;
Wet stretching step of multi-stage stretching of three or more stages in a coagulating solution containing a polar amide-based solvent for the meta-aramid fibers to be spun;
A water washing/drying step of washing and drying the wet-stretched meta-aramid fibers;
Including a hot stretching step of hot stretching the dried meta aramid fibers at a high temperature,
Meta-aramid fiber manufacturing method with improved dyeability and glossiness, characterized in that the wet stretching ratio of the wet stretching step is greater than the hot stretching ratio of the hot stretching step. According to claim 1,
Method for producing meta-aramid fiber with improved dyeability and glossiness, characterized in that the wet stretching ratio of the wet stretching step is 2.0 to 4.0. According to claim 1,
Method for producing meta-aramid fiber with improved dyeability and glossiness, characterized in that the hot draw ratio of the hot stretching step is 1.1 to 1.9. According to claim 1,
The wet stretching step is a method for producing meta aramid fibers with improved dyeability and glossiness, characterized in that wet stretching with multi-stage stretching of 3 to 4 stages. According to claim 1,
When the wet stretching ratio of the wet stretching step is dw, the hot stretching ratio of the hot stretching step is dh, and the multi-stage number of the wet stretching step is nb, the following formula is satisfied. Meta aramid fiber manufacturing method with improved dyeability and glossiness .
Formula (dw/dh)*nb≥5.5 A meta-aramid fiber with improved dyeability and glossiness, characterized in that it is produced by the meta-aramid fiber manufacturing method of any one of claims 1 to 5. According to claim 6,
Meta aramid fiber with improved dyeability and glossiness, characterized in that the dyeing concentration (K / S) of the meta aramid fiber is 20 or more.

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