Aramid dope-dyed yarn and method of making same

Abstract

The present application relates to an aramid dope-dyed yarn and a method for manufacturing the same, the aramid dope-dyed yarn being manufactured by mixing spinning a master batch dope including a meta-aramid dope and a pigment with a mixed dope of the meta-aramid dope, wherein the meta-aramid dope is polymerized from m-phenylene diamine (MPD) and isophthaloyl chloride (IPC), and the present application can provide an aramid dope-dyed yarn having excellent light fastness with little color deviation due to uniform dispersion of the pigment.

Description

TECHNICAL FIELD

[0001] The present application relates to aramid yarns dyed in stock solution and a method for preparing the same, and more particularly, to meta-aramid yarns dyed in stock solution having a small color deviation and excellent light fastness and a method for preparing the same. BACKGROUND

[0002] Generally, polyamide-based synthetic resins are classified into aliphatic polyamides and aromatic polyamides. The aliphatic polyamides are generally known by the trade name "Nylon", and the aromatic polyamides are known by the trade name "Aramid".

[0003] The aliphatic polyamides, particularly Nylon 6 and Nylon 6,6, etc., are the most commonly used thermoplastic engineering plastics, and their important application fields are not only fibers, but also molding materials for various fields. Nylon resins used in the molding field are reinforced with mineral or glass fibers to make reinforced plastics as composite materials in order to improve their flame retardancy and impact resistance, and to reduce the price and improve mechanical properties such as elastic modulus.

[0004] Aromatic polyamides, which are known by the trade names such as NOMEX, KEVLAR, etc., and were developed in the 1960s, are developed to improve the heat resistance of nylon, which is an aliphatic polyamide, and have excellent heat resistance and high tensile strength that can be used as flame-retardant fiber fabrics, tire cords, and other fiber applications.

[0005] General aliphatic polyamides refer to synthetic resins having aliphatic hydrocarbons bonded between amide groups, and aramid refers to synthetic resins having phenyl groups bonded between amide groups, with 85% of the amide bonds being bonded to two aromatic rings. The aliphatic hydrocarbons of aliphatic polyamides easily undergo molecular motion if heated, and in contrast, the benzene rings of aromatic polyamides have rigid molecular chains, so that even if heated, the molecules do not easily move, thus being stable to heat, and having a high elastic modulus, thus showing many differences in characteristics from general aliphatic polyamides.

[0006] Aromatic polyamides are classified into para-aramid and meta-aramid, and a representative example of para-aramid is KEVLAR developed by DuPont. In para-aramid, benzene rings are bonded to amide groups at para positions. Since the molecular chain is very hard and has a linear structure, it has high strength, particularly high elastic modulus, and excellent impact absorption performance, and is used as a material for bulletproof vests, bulletproof helmets, safety gloves or boots, fireproof clothing, etc., as well as sports equipment such as tennis rackets, motorboats, hockey sticks, fishing lines, and golf clubs, and in industry, for FRP (Fiber Reinforced Plastic), asbestos replacement fibers, etc. A representative example of meta-aramid is NOMEX developed by DuPont and CONEX developed by Teijin. In meta-aramid, benzene rings are bonded to amide groups at meta positions, and has strength and elongation similar to ordinary nylon, but has excellent thermal stability, is lighter than other heat-resistant materials, and can absorb sweat to some extent, thus having the advantage of being cool. Initially, the color was limited to several colors, but recently, a variety of colors including fluorescent colors have been produced. It is used as a heat-resistant clothing material for fireproof clothing, racing suits for race car drivers, spacesuits for astronauts, work clothes, etc., and in industry, as a high-temperature filter, etc.

[0007] As one of the methods of using such aramid fibers, a dope dyeing yarn is prepared by adding a pigment to a meta-aramid dope. However, when a dope dyeing yarn is manufactured using a meta-aramid dope, the added pigment lowers the physical properties of the dope dyeing yarn, and particularly, a serious color deviation can occur due to uneven dispersion of the pigment, and has a problem of low light fastness.

[0008] Prior Art Document 1: Korean Patent No. 10-1558064 SUMMARY

[0009] TECHNICAL PROBLEM

[0010] The present application has been developed in order to solve the above problems, and an object of the present application is to provide a meta-aramid dope dyeing yarn in which a pigment is uniformly dispersed in a high-viscosity meta-aramid polymer and light fastness is improved, and a method of manufacturing the same.

[0011] The above and other objects and advantages of the present application will become clear to those skilled in the art from the following description of preferred embodiments.

[0012] TECHNICAL SOLUTION

[0013] The object is achieved by an aramid dope-dyed yarn prepared by mixing spinning a master dope including meta-aramid dope and a pigment with a mixed dope of the meta-aramid dope, wherein the meta-aramid dope is polymerized from m-phenylene diamine (MPD) and isophthaloyl chloride (IPC).

[0014] Preferably, the aramid dope-dyed yarn can include 0.01 to 2.5 parts by weight of the pigment with respect to 100 parts by weight of the meta-aramid fiber.

[0015] Preferably, the light fastness of the aramid dope-dyed yarn can be 4 to 5 degrees according to the KS K ISO 105-B02 measurement method after exposure to a xenon arc light source for 40 hours.

[0016] Preferably, the undecomposed residual amount of the pigment can be 95% or more at 350°C.

[0017] Preferably, the strength of the aramid dope-dyed yarn can be 3.0 to 5.5 g / d.

[0018] Preferably, the single yarn fineness of the aramid dope-dyed yarn can be 0.5 to 5.0 denier.

[0019] In addition, the object is achieved by a method of manufacturing an aramid dope-dyed yarn, the method including: a first step of preparing a meta-aramid dope polymerized from m-phenylene diamine (MPD) and isophthaloyl chloride (IPC); a second step of dispersing and mixing a pigment in the meta-aramid dope to prepare a master dope; a third step of mixing the meta-aramid dope in the master dope to prepare a mixed dope; and a fourth step of spinning the mixed dope to prepare a dope-dyed yarn.

[0020] Preferably, the master dope of the second step can include 0.1 to 10% by weight of the pigment.

[0021] Preferably, the solution viscosity of the master dope can be 5 to 50 poise at 25°C.

[0022] Preferably, the solution viscosity of the mixed dope can be 150 to 300 poise at 100°C and 350 to 650 poise at 80°C.

[0023] Preferably, the dispersion particle size of the pigment in the master dope can be less than 5 µm.

[0024] Preferably, the fourth step can be performed by dry spinning.

[0025] Invention Effects

[0026] According to an embodiment of the present invention, aramid solution-dyed yarn and its preparation method can provide aramid solution-dyed yarn with small color deviation due to uniform pigment dispersion and excellent light fastness.

[0027] However, the effects of the present invention are not limited to those mentioned above, and other effects not mentioned are clearly understood by those skilled in the art from the following description. Attached Figure Description

[0028] Figure 1 This is a flowchart illustrating a method for preparing aramid solution-dyed yarn according to an embodiment of the present invention. Detailed Implementation

[0029] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that those skilled in the art can readily implement the invention. However, the present invention can be embodied in many different forms and is not limited to the embodiments described herein.

[0030] In the accompanying drawings, the thickness is enlarged to clearly show multiple layers and regions. Throughout the specification, similar reference numerals are used for similar parts. When referring to a layer, film, region, plate, etc., as being "above" other parts, this includes not only the case where it is "directly above" other parts, but also the case where other parts exist between it. Conversely, when referring to a part as being "directly above" other parts, it means that there are no other parts between it.

[0031] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. In case of conflict, the specification including the definitions shall prevail. Furthermore, although similar or equivalent methods and materials may be used in the implementation or testing of this invention, suitable methods and materials are described in this specification.

[0032] Figure 1 This is a flowchart illustrating a method for preparing aramid solution-dyed yarn according to an embodiment of the present invention.

[0033] Reference Figure 1The method for preparing aramid solution-dyed yarn according to an embodiment of the present invention includes: a first step (S101) of preparing a meta-aramid solution polymerized from m-phenylene diamine (MPD) and isophthaloyl chloride (IPC); a second step (S102) of dispersing and mixing pigments in the meta-aramid solution to prepare a masterbatch solution; a third step (S103) of mixing the meta-aramid solution in the masterbatch solution to prepare a mixed solution; and a fourth step (S104) of spinning the mixed solution to prepare solution-dyed yarn.

[0034] As described above, in this invention, the pigment is not directly mixed with the meta-aramid dope polymerized in the first step. Instead, the pigment is mixed with other meta-aramid dopes to prepare a masterbatch dope (second step), and then mixed with the meta-aramid dope polymerized in the first step to prepare aramid dope dyed yarn. If the pigment is directly dispersed in the meta-aramid polymer without the second step (masterbatch step), the high viscosity of the meta-aramid polymer itself makes dispersion difficult. Overcoming this problem and performing dispersion requires high physical / equipment requirements, resulting in investment exceeding the necessary equipment and reducing economic efficiency. Therefore, by using a masterbatch dope with a lower viscosity, the pigment is pre-dispersed in the meta-aramid, and simultaneously the meta-aramid is wetted on the pigment surface. This improves the effect of maintaining the dispersion in the masterbatch in the next step, i.e., the third step of mixing the masterbatch with the meta-aramid.

[0035] The first step (S101) in preparing the meta-aramid stock solution by polymerizing m-phenylene diamine (MPD) and isophthaloyl chloride (IPC) is to polymerize meta-aramid with m-phenylene diamine and isophthaloyl chloride to prepare the meta-aramid stock solution.

[0036] The solution viscosity of the meta-aramid dope prepared in the first step (S101) is preferably 150 to 300 poise at 100°C and 350 to 650 poise at 80°C. From the perspective of fiber physical properties, the molecular weight is preferably in the range of 300,000 to 400,000 with a weight average molecular weight. When the weight average molecular weight of the meta-aramid dope is below 300,000, the fiber strength and heat resistance are low. When the weight average molecular weight of the meta-aramid dope is above 400,000, the spinning processability is poor, and it is difficult to prepare uniform fiber products.

[0037] Next, in the second step (S102), the pigment is dispersed and mixed in the meta-aramid dope to prepare the masterbatch dope, and the pigment is dispersed and mixed in the meta-aramid dope prepared in the first step (S101) to prepare the masterbatch dope. At this time, the masterbatch dope preferably contains 0.1 to 10% by weight of pigment. When the pigment content is less than 0.1% by weight, a shielding effect caused by meta-aramid occurs in the fiberization process of the high-viscosity meta-aramid polymer, making it difficult to achieve the desired color. This results in an increase in the amount of pigment used to achieve the desired color, increasing manufacturing costs. Furthermore, when the pigment content exceeds 10% by weight, the risk of pigment re-aggregation increases, thereby increasing the possibility of instability induced during the fiberization process. In contrast, the present invention, through the uniform distribution of pigment, not only achieves color with a relatively small pigment content, reducing costs, but also prevents the deterioration of physical properties caused by pigment.

[0038] Preferably, the viscosity of the masterbatch stock solution prepared in the second step (S102) is 5 to 50 poise at 25°C. If the viscosity of the masterbatch stock solution is less than 5 poise at 25°C, precipitation will occur over time after pigment dispersion treatment, which is detrimental to storage. If the viscosity of the masterbatch stock solution exceeds 50 poise at 25°C, there will be localized uneven dispersion when preparing the mixed stock solution. In this case, the viscosity of the masterbatch stock solution is preferably adjusted using a polar amide solvent.

[0039] Ideally, the pigment dispersion particle size in the masterbatch solution should be less than 5 μm. When the pigment dispersion particle size is greater than 5 μm, the pigment acts as a foreign object in the fiberization process (spinning, subsequent treatment), inducing uneven physical stress, which can lead to problems such as poor spinnability or breakage in the spinning process.

[0040] Preferred pigments include at least one pigment selected from organic pigments, inorganic pigments and fluorescent pigments, with organic pigments with high melting point and high thermal stability being more preferred.

[0041] Next, in the third step (S103) of preparing a mixed stock solution by mixing the meta-aramid stock solution with the masterbatch stock solution, the meta-aramid stock solution prepared in the first step (S103) is mixed with the masterbatch stock solution prepared in the second step (S102).

[0042] At this point, it is preferable to mix 1,000 to 4,000 parts by weight of meta-aramid dope relative to 100 parts by weight of masterbatch dope. When the content of meta-aramid dope is less than 1,000 parts by weight, the viscosity of the mixed dope decreases, making it unsuitable for the spinning process. Furthermore, when the content of meta-aramid dope exceeds 4,000 parts by weight, a high-temperature spinning environment is required to ensure spinnability, necessitating the input of unnecessary heat sources, which is economically unreasonable and will damage the uniformity of the final fiber product. The concentration of meta-aramid decreases, and the shielding effect caused by meta-aramid is detrimental to the color presentation of pigments.

[0043] The preferred viscosity of the mixed dosing solution is 150 to 300 poise at 100°C and 350 to 650 poise at 80°C. If the viscosity of the mixed dosing solution is less than 150 poise at 100°C or less than 350 poise at 80°C, there is a problem of poor spinning processability, as the fiber cannot withstand the tension it experiences during the spinning process. If the viscosity exceeds 300 poise at 100°C or exceeds 650 poise at 80°C, it is difficult to uniformly extrude the fibers from the nozzle during the spinning process. The viscosity of the mixed dosing solution is adjusted by adding a polar amide solvent during the preparation of the masterbatch solution in the second step (S102), and by adjusting the viscosity of the mixed dosing solution based on the mixing ratio during the mixing of the masterbatch solution and the meta-aramid solution in the third step (S103).

[0044] The masterbatch solution containing pigment mixed in the meta-aramid solution, as described above, has a melt viscosity of 5 to 50 poise at 25°C. Therefore, in the third step (S103), by mixing the meta-aramid solution into the masterbatch solution, a relatively high-viscosity meta-aramid solution can be mixed into a relatively low-viscosity masterbatch solution to improve dispersibility. Generally, if pigment is added, the strength of the prepared filament or fiber decreases; however, the above-described process improves pigment dispersibility, saves the amount of pigment required to achieve the desired color, and increases fiber strength as pigment is saved.

[0045] Next, in the fourth step (S104) of spinning the mixed solution to prepare solution-dyed yarn, the mixed solution prepared in the third step (S103) is spun to prepare aramid solution-dyed yarn. At this time, dry spinning is preferred.

[0046] The aramid solution-dyed yarn of an embodiment of the present invention prepared according to the above method is prepared by mixing and spinning meta-aramid polymerized from m-phenylene diamine (MPD) and isophthaloyl chloride (IPC) with pigment.

[0047] The aramid solution-dyed yarn prepared according to the above preparation method preferably contains 0.01 to 2.5 parts by weight of pigment relative to 100 parts by weight of meta-aramid fibers. When the pigment content is less than 0.01 parts by weight relative to 100 parts by weight of meta-aramid fibers, a shielding effect caused by the meta-aramid fibers occurs during the fiberization process of high-viscosity meta-aramid fibers, making it difficult to achieve the desired color. Reducing the pigment content increases the preparation cost compared to achieving the same color. Furthermore, when the pigment content exceeds 2.5 parts by weight relative to 100 parts by weight of meta-aramid fibers, the risk of pigment re-agglomeration increases, thus increasing the possibility of instability induced during the fiberization process of meta-aramid fibers.

[0048] In aramid solution-dyed yarn, it is preferable that the amount of pigment remaining undecomposed at a high temperature of 350°C is 95% or more. This is related to the heat resistance of the organic pigment itself and is a required characteristic for achieving durability under high-temperature conditions during the fiberization process. When the amount of undecomposed residue is less than 95%, changes in content and color composition are induced due to the high-temperature conditions in the preparation process, resulting in color changes in the final product. In addition, the possibility of discoloration increases due to the high spinning temperature conditions during dry spinning and the heat treatment temperature conditions in subsequent processing steps.

[0049] The preferred aramid solution-dyed yarn, after being exposed to a xenon arc light source for 40 hours, exhibits a lightfastness grade of 4 to 5 as measured by the KS K ISO 105-B02 method. As described above, the aramid solution-dyed yarn of one embodiment of the present invention achieves high lightfastness through the uniform dispersion of the pigment itself.

[0050] Furthermore, the strength of the solution-dyed aramid yarn is preferably 3.0 to 5.5 g / d. This corresponds to the strength of aramid yarn (Raw White aramid) without organic pigment particles. Typically, solution-dyed yarn experiences a decrease in strength due to the addition of pigments. However, in this invention, the use of pigments for color presentation can be minimized, and uniform pigment distribution can be achieved. Thus, even with the presence of organic pigment particles, the strength of the aramid yarn (Raw White aramid) can be expressed as good as that of aramid yarn (Raw White aramid) without pigment particles.

[0051] The preferred aramid solution-dyed yarn has a single yarn fineness of 0.5 to 5.0 denier. Typically, the physical properties of aramid solution-dyed yarn decrease due to the addition of pigments, particularly the pigment content. However, in the aramid solution-dyed yarn of one embodiment of the present invention, by improving pigment dispersibility, a single yarn fineness of 0.5 to 5.0 denier can be achieved even with the addition of pigments used to achieve the color. That is, the pigment content of the solution-dyed yarn varies depending on the desired color, thus affecting the spinning / subsequent processing of the fiberization process. However, given that the aramid solution-dyed yarn of the present invention is primarily intended for apparel use, a single yarn fineness of 0.5 to 5.0 denier can be achieved through subsequent processing (spinning, weaving) steps.

[0052] The present invention will now be described in more detail through embodiments. These embodiments are used to describe this description in more detail and are not intended to limit the scope of the invention to these embodiments.

[0053] [Example]

[0054] [Example 1]

[0055] Meta-aramid stock solution was prepared by polymerization of m-phenylene diamine (MPD) and isophthaloyl chloride (IPC) (Araven, Toray Advanced Materials Co., Ltd.).

[0056] Then, a masterbatch solution was prepared by mixing 1% by weight of pigment into the prepared meta-aramid solution. At this time, dispersion treatment was performed to ensure that the pigment particle size distribution in the masterbatch solution was less than 5 μm. Furthermore, the viscosity of the masterbatch solution was 5 poise at 25°C.

[0057] Then, a mixed stock solution was prepared by mixing 2,000 parts by weight of meta-aramid stock solution with 100 parts by weight of masterbatch stock solution. At this time, the solution viscosity of the mixed stock solution was 150 poise at 100°C and 350 poise at 80°C.

[0058] Then, the prepared mixed solution was dry-spun to prepare solution-dyed yarn.

[0059] [Example 2]

[0060] Except that the pigment content of the prepared masterbatch solution was set to 5% by weight, the solution-dyed yarn was prepared in the same manner as in Example 1.

[0061] [Example 3]

[0062] Except that the pigment content of the prepared masterbatch solution was set to 10% by weight, the solution-dyed yarn was prepared in the same manner as in Example 1.

[0063] [Example 4]

[0064] Except that the pigment content of the prepared masterbatch solution was set to 0.1% by weight, the solution-dyed yarn was prepared in the same manner as in Example 1.

[0065] [Example 5]

[0066] Except for setting the solution viscosity of the masterbatch stock solution to 50 poise at 25°C, and the solution viscosity of the mixed stock solution to 300 poise at 100°C and 650 poise at 80°C, solution-dyed yarn was prepared in the same manner as in Example 1.

[0067] [Comparative Example]

[0068] [Comparative Example 1]

[0069] Except for not performing dispersion treatment to ensure that the pigment particle size distribution is less than 5 μm, solution-dyed yarn was prepared in the same manner as in Example 1.

[0070] [Comparative Example 2]

[0071] Except that the pigment content of the prepared masterbatch solution was set to 0.05% by weight, the solution-dyed yarn was prepared in the same manner as in Example 1.

[0072] [Comparative Example 3]

[0073] Except that the pigment content of the prepared masterbatch solution was set to 11% by weight, the solution-dyed yarn was prepared in the same manner as in Example 1.

[0074] [Comparative Example 4]

[0075] Except for setting the solution viscosity of the masterbatch stock solution to 4 poise at 25°C, and the solution viscosity of the mixed stock solution to 140 poise at 100°C and 340 poise at 80°C, solution dyed yarn was prepared in the same manner as in Example 1.

[0076] [Comparative Example 5]

[0077] Except for setting the solution viscosity of the masterbatch stock solution to 51 poise at 25°C, and the solution viscosity of the mixed stock solution to 310 poise at 100°C and 660 poise at 80°C, solution-dyed yarn was prepared in the same manner as in Example 1.

[0078] The physical properties of the solution-dyed yarns prepared in Examples 1 to 5 and Comparative Examples 1 to 5 were evaluated by the following experimental examples, and the results are shown in Tables 1 and 2.

[0079] [Experimental Example]

[0080] (1) Whether there is visible sediment

[0081] After placing the prepared masterbatch stock solution in a transparent container at 25°C, observe it visually for 30 days to confirm the interface caused by precipitation. After observing whether there is precipitation, mark the situation where precipitation occurs as "present", the situation where no precipitation occurs as "no", and the situation where the degree of precipitation is intermediate as "medium".

[0082] (2) Particle size measurement

[0083] The dispersion particle size of the prepared solution-dyed yarn was measured over 30 days using a simulated particle size analyzer (grind gauge).

[0084] (3) Color difference (ΔE) measurement

[0085] For the prepared masterbatch stock solution, the color difference was measured using a colorimeter (Konica Minolta, cm-3600a) after 30 days based on the self-sampling time point.

[0086] (4) Measurement of light fastness

[0087] The light fastness of the prepared solution-dyed yarn was measured after 40 hours of exposure to a xenon arc light source according to the KS K ISO 105-B02 method.

[0088] (5) Measurement of yarn fineness and strength

[0089] For the prepared solution-dyed yarn, the fineness and strength of the single yarn were measured using a Vibroskop instrument at 25°C and 65% RH.

[0090] Table 1

[0091]

[0092] Table 2

[0093]

[0094]

[0095] As shown in Tables 1 and 2 above, the particle size, strength, yarn fineness, and lightfastness of Examples 1 to 5 all meet the requirements of the invention. Furthermore, Examples 1 to 4 do not exhibit precipitation after 30 days, maintaining a particle size of less than 5 μm and showing minimal color difference variation.

[0096] Conversely, Comparative Example 1, with a particle size distribution of 5 μm or larger, showed precipitation over time, indicating that the dispersed particle size was too large to be used for spinning aramid solution-dyed yarn. In particular, Comparative Example 1 did not show precipitation initially, but precipitation occurred after 5 days. The dispersed particle size not only showed a value of 5 μm or larger initially, but also gradually increased after 30 days, and the color difference became unmeasurable after 5 days.

[0097] Furthermore, it is known that in Comparative Example 2 with insufficient pigment, the particle size increased over time, making it unsuitable for spinning aramid solution-dyed yarn.

[0098] Furthermore, it is known that in Comparative Example 3, the excessive amount of pigment precipitated over time, resulting in excessively large dispersed particles that could not be used for spinning aramid solution-dyed yarn.

[0099] Furthermore, it is known that in Comparative Example 4, where the solution viscosity of the masterbatch solution and the mixed solution is low, precipitation occurs over time, and the dispersed particle size is too large to be used for spinning aramid solution-dyed yarn.

[0100] Furthermore, it is known that in Comparative Example 5, the solution viscosity of the masterbatch solution and the mixed solution was high, and precipitation occurred rapidly. The dispersed particle size was too large, making it unsuitable for spinning aramid solution-dyed yarn.

[0101] Furthermore, it can be confirmed that, except for Comparative Example 2, all other comparative examples experienced precipitation or agglomeration over time. When measuring color difference, some of the measured values ​​were uneven, making it impossible to ensure the reliability of the data, and ultimately the color difference could not be measured.

[0102] The preferred embodiments of the present invention have been described in detail above, but the scope of the present invention is not limited thereto. Various modifications and improvements made by those skilled in the art using the basic concepts of the present invention as defined in the following claims also fall within the scope of the present invention.

Claims

1. An aramid solution-dyed yarn, prepared by spinning a masterbatch solution comprising meta-aramid solution and pigment mixed with a mixed masterbatch solution of the meta-aramid solution, wherein the meta-aramid solution is polymerized from m-phenylenediamine and isophthaloyl chloride, and the pigment content in the masterbatch solution is 0.1% to 10% by weight. The pigment dispersion particle size in the masterbatch stock solution is less than 5. , The viscosity of the masterbatch stock solution is 5 to 50 poise at 25°C. The viscosity of the mixed stock solution is 150 to 300 poise at 100°C and 350 to 650 poise at 80°C.

2. The aramid solution-dyed yarn according to claim 1, wherein, The aramid solution-dyed yarn contains 0.01 to 2.5 parts by weight of pigment relative to 100 parts by weight of meta-aramid fiber.

3. The aramid solution-dyed yarn according to claim 1, wherein, The lightfastness of the aramid solution-dyed yarn, after being exposed to a xenon arc light source for 40 hours, was measured according to the KS K ISO 105-B02 method and was grade 4 to 5.

4. The aramid solution-dyed yarn according to claim 1, wherein, The pigment has an undecomposed residue of over 95% at 350°C.

5. The aramid solution-dyed yarn according to claim 1, wherein, The strength of the aramid solution-dyed yarn is 3.0 to 5.5 g / d.

6. The aramid solution-dyed yarn according to claim 1, wherein, The fineness of the single yarn of the aramid solution-dyed yarn is 0.5 to 5.0 denier.

7. A method for preparing aramid solution-dyed yarn, comprising: The first step is to prepare a meta-aramid stock solution polymerized from m-phenylenediamine and isophthaloyl chloride; The second step involves dispersing and mixing the pigment in the meta-aramid solution to prepare the masterbatch solution. The third step is to mix the meta-aramid solution with the masterbatch solution to prepare a mixed solution; The fourth step is to spin the mixed solution to prepare solution-dyed yarn. The masterbatch solution in the second step contains 0.1 to 10% by weight of the pigment. The pigment dispersion particle size in the masterbatch stock solution is less than 5. , The viscosity of the masterbatch stock solution is 5 to 50 poise at 25°C. The viscosity of the mixed stock solution is 150 to 300 poise at 100°C and 350 to 650 poise at 80°C.

8. The method for preparing aramid solution-dyed yarn according to claim 7, wherein, The fourth step is performed using dry spinning.

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