KR102440861B1 - Method for manufacturing lyocell fiber and lyocell fiber therefrom - Google Patents

Abstract

The present invention relates to a method for producing a lyocell fiber capable of exhibiting a low fibrillation degree by treating the crosslinking agent without an additional process in treating the lyocell fiber with a crosslinking agent. In addition, the present invention relates to a lyocell fiber manufactured by the above manufacturing method, which has a low degree of fibrillation and is easy to process in a post process such as weaving and dyeing, so that it can be suitably applied for uses such as high-quality clothing.

Description

Method for manufacturing lyocell fiber and lyocell fiber prepared therefrom

The present invention provides a method for producing a lyocell fiber that can exhibit a low degree of fibrillation without an additional process such as steaming by treating the lyocell fiber with a novel crosslinking agent during the general lyocell fiber manufacturing process, and manufacturing therefrom It relates to a lyocell fiber.

As a method of manufacturing a fiber using a renewable cellulose raw material, in the case of rayon fiber by a conventional viscose process, there are environmental problems, etc., and recently developed countries are gradually closing rayon production bases. Accordingly, lyocell fibers produced by an eco-friendly method while having physical properties equivalent to those of rayon fibers are widely used for clothing or industrial purposes. Lyocell fibers are generally manufactured by spinning a dope in which cellulose is dissolved in NMMO (N-methyl-morpholine-N-oxide), coagulating the spun fibers, and then washing and drying them. Theoretically, it is environmentally and economically advantageous because 100% of NMMO and water are recycled and regenerated.

Lyocell fibers have high tenacity under certain conditions and wet conditions, but are known to be sensitive to fibrillation. In particular, fibrillation occurs when subjected to mechanical friction during wet processing, such as in a water washing process, which is known to be because hydrogen bonds between cellulose molecules decrease in wet or swollen state, resulting in mechanical stress caused by friction between fibers and processing machines. In some applications, fibril is also a major characteristic of fibers, but in general, fibrils impair the efficiency of the fiber production process, adversely affect post-processes such as weaving the fabric, and lower the fastness to washing. acts as a disadvantage of In addition, fibrils appear on the fiber surface and become a factor that deteriorates the texture of the fiber surface and the quality of the final product, as well as an additional process for removing the fibrils is required, which increases the production cost.

Research to reduce or eliminate the tendency to fibrillation is continuing, to reduce or eliminate the tendency to fibrillation by appropriately selecting the spinning conditions, or to reduce or eliminate the tendency to fibrillation by a chemical post-treatment process using a crosslinking agent A removal method is being carried out.

Korean Patent Publication No. 1999-0083163 discloses that lyocell fibers in an undried or dried state are treated with a mixed aqueous solution containing a compound having 2 to 6 functional groups reactive with cellulose and several inorganic alkalis to reduce the tendency to fibrillation. How to do it is described. Among the compounds used herein, the important ones are polyhalogenated polyazines or compounds containing polyazine rings having two or more vinylsulfone groups and their precursors. However, in the lyocell fiber treated with these compounds, hydrolysis of cellulose molecules occurred in the scouring and dyeing process, and the fibrillation reducing effect was lost and fibrils were generated again.

Korean Patent Laid-Open No. 2011-0025204 discloses a method for reducing fibrillation of lyocell fibers by using a 1,3,5-triazine compound as a crosslinking agent. However, in the case of the compound described in the above patent, there is a problem in that an appropriate buffer material must be added according to pH in order to be used as a crosslinking agent for lyocell fibers, and a separate process for treating the buffer material must be added.

In Korean Patent Laid-Open No. 2005-0030477, a lyocell is passed through an aqueous solution containing 1,3,5-triacryloylhexahydro-1,3,5-triazine (TAF) and heat-treated in a high-temperature, moist-heat state. Methods for reducing fibrillation by causing chemical crosslinking are described.

Although the method of treating the TAF is a process used to prevent fibrillation of lyocell fibers until recently, spinning, coagulation, and washing are performed by TAF that does not react with water, followed by separate steaming It is necessary to add a process, and productivity and economic efficiency are low in that a process is added rather than simplifying the manufacturing process. In addition, since TAF has contact toxicity and inhalation toxicity, there is a problem in that it is necessary to pay attention to handling in the process. Therefore, there is a need for a novel crosslinking agent capable of reducing or eliminating the fibrillation tendency of lyocell fibers, development of a novel anti-fibrillation process, and development of lyocell fibers prepared therefrom.

Republic of Korea Patent Publication No. 1999-0083163 Republic of Korea Patent Publication No. 2005-0030477 Republic of Korea Patent Publication No. 2011-0025204

The present invention is to provide a method for producing a lyocell fiber capable of exhibiting a low degree of fibrillation by using a novel crosslinking agent in the lyocell fiber.

In addition, the present invention is to provide a lyocell fiber, which is manufactured by the above manufacturing method, has a low degree of fibrillation and is easy to process in a post-process such as weaving and dyeing, and is suitable for use in high-quality clothing, etc.

A method of manufacturing a lyocell fiber according to an embodiment of the present invention comprises: spinning a dope for manufacturing a lyocell through a spinneret; passing the spun dope through a coagulation bath to solidify into filaments; washing the filaments that have passed through the coagulation bath; treating the washed filament with an emulsion; Including the step of drying the filaments treated with the oil agent, the oil agent and the crosslinking agent are simultaneously treated in the oil agent treatment step.

In addition, the crosslinking agent in the embodiment provides a method for producing a lyocell fiber that is at least two or more functional groups capable of reacting with a hydroxyl group in the cellulose molecule of the lyocell fiber. The crosslinking agent may include an isocyanate group as a functional group.

According to another embodiment of the present invention, the step of spinning a dope for manufacturing lyocell through a spinneret; passing the spun dope through a coagulation bath to solidify into filaments; washing the filaments that have passed through the coagulation bath; treating the washed filament with an emulsion; drying the filament treated with the emulsion; and forming a crimp on the filament, wherein the oil agent and the crosslinking agent are simultaneously treated in the oil agent treatment step. In addition, the crosslinking agent may be at least two or more functional groups capable of reacting with a hydroxyl group in the cellulose molecule of the lyocell fiber, and the functional group may be an isocyanate group.

A method for producing a lyocell fiber according to another embodiment of the present invention comprises: spinning dope for lyocell production through a spinneret; passing the spun dope through a coagulation bath to solidify into filaments; washing the filaments that have passed through the coagulation bath; treating the washed filament with an emulsion; treating the emulsion-treated filament with a crosslinking agent; It may include drying the filaments treated with the emulsion and the crosslinking agent.

A method for producing a lyocell fiber according to another embodiment of the present invention comprises: spinning dope for lyocell production through a spinneret; passing the spun dope through a coagulation bath to solidify into filaments; manufacturing a staple by cutting the filament that has passed through the coagulation bath; washing the staples; treating the washed staple with an emulsion and a crosslinking agent; and drying the staple.

In addition, in another embodiment of the present invention, it provides a lyocell fiber treated with a crosslinking agent comprising the following formula (1).

In the above formula, R1, R2 and R3 are each independently the same or different functional groups R-N=C=O, wherein R is each independently an alkyl group, alkenyl group, alkynyl group, or aryl group having 2 to 20 carbon atoms.

In addition, in the lyocell fiber treated with the crosslinking agent comprising Formula 1, R1, R2 and R3 of Formula 1 are each independently the same functional group as R-N=C=O, wherein R is an alkyl group having 2 to 20 carbon atoms. can

The present invention treats lyocell fibers with a novel crosslinking agent in order to reduce the degree of fibrillation, and processes other than general spinning, coagulation, washing, tanning and drying processes to produce lyocell fibers, for example, steaming It is possible to reduce the degree of fibrillation of the lyocell fiber without adding (steaming).

1 is a schematic diagram showing an example of a spinning apparatus for producing a lyocell fiber according to an embodiment of the present invention.
Figure 2 is a schematic diagram showing an example of a spinning apparatus for a method for producing a lyocell fiber using the conventional TAF as a crosslinking agent.
3 is a photograph of a lyocell fiber with reduced fibrils treated with a novel crosslinking agent according to an embodiment of the present invention.
Figure 4 is a photograph of the lyocell fibers in which fibrils are not treated with a crosslinking agent.

Hereinafter, the present invention will be described in more detail.

The lyocell fiber according to an embodiment of the present invention comprises: spinning dope for lyocell production through a spinneret (S1); passing the spun dope through a coagulation bath to solidify into filaments (S2); washing the filaments that have passed through the coagulation bath (S3); treating the washed filament with an emulsion (S4); It is prepared by a general manufacturing method including the step of drying the emulsion-treated filament (S5). In step S4, which is the oil agent treatment step, an oil agent including a crosslinking agent is treated on the Lyocell fiber to reduce the fibrillation degree of the Lyocell fiber produced.

The fibrillation of lyocell fibers occurs as the orientation of the lyocell fiber polymers is high and the intermolecular entanglement in the fibers is reduced. . Among methods for minimizing fibrillation, in a chemical method for reducing fibrillation by inducing crosslinking of hydroxyl groups in cellulose molecules of lyocell fibers, conventionally, 1,3,5-triacrylonitrile is typically used. Ilhexahydro-1,3,5-triazine (TAF) was used as a crosslinking agent. It is known that crosslinking proceeds through the Michael addition reaction of the hydroxyl group in the cellulose molecule of the Lyocell fiber with the acrylamido group in the TAF.

Treatment of the TAF cross-linking agent to the lyocell fiber is generally cross-linked at 110° C. for about 20 minutes to 1 hour after immersion in a TAF solution after spinning, coagulation and water washing processes, as schematically shown in FIG. 2 . However, in the method of using the TAF crosslinking agent, since TAF does not react with water, a steaming step 201 of performing the reaction under high temperature steam conditions is required. In addition, since a water washing process is further required after the steaming process, the conventional process has a very disadvantageous aspect in terms of energy consumption.

On the other hand, in one embodiment of the present invention, in the process of treating the oil agent, the oil agent and the crosslinking agent are present together in the oil agent solution so that the oil agent is treated on the Lyocell fiber and the crosslinking agent can act on the Lyocell fiber at the same time, or No need for an additional time-consuming and energy-consuming steaming process due to the presence of the containing reaction bath. For this, a novel crosslinking agent must be introduced, and the crosslinking agent preferably has high reactivity with the hydroxyl group of cellulose.

The oil agent used may have various compositions depending on the purpose used after the lyocell fiber is manufactured, and is usually present in an aqueous solution state. Therefore, in the case of a crosslinking agent having high reactivity with a hydroxyl group, it may react with moisture in the oil. Therefore, when the crosslinking agent is present together with the oil, it is necessary to properly treat it so that it does not react with moisture so that the reaction site of the functional group is activated in the drying step. may be needed

Hereinafter, a method of manufacturing a lyocell fiber according to an embodiment of the present invention is described in detail step by step with reference to FIG. 1 . 1 schematically shows an apparatus and process used in a method for manufacturing a lyocell fiber according to an embodiment of the present invention.

Step S1

Step S1 is a step of spinning dope for lyocell production through a spinneret. The dope for lyocell production includes NMMO aqueous solution as a solvent component and pulp capable of supplying cellulose. The pulp is not particularly limited as long as it is a source of cellulose and may be derived from waste paper, wood, and the like. In order to reduce fibrillation through raw materials, linter pulp with a short fiber length separated from cotton may be used, or bamboo pulp extracted from bamboo may be used.

The dope for spinning may include an aqueous NMMO solution at a level of 60 to 94% by weight as a solvent component. When the content of the NMMO aqueous solution is less than 60% by weight, the dissolution viscosity is greatly increased, which is not preferable, and when it exceeds 94% by weight, the spinning temperature must be increased, so that decomposition of NMMO may occur.

The spinneret serves to allow the spinning dope to pass through and form a fibrous filament, and the formed filament is discharged as a coagulating solution through the air gap. The process of discharging the dope for spinning from the spinneret may be performed at 80° C. to 130° C.

Step S2

Step S2 is a step of coagulating the spun dope into a filament by passing it through the coagulation baths 13 and 14. The spinning dope formed into filaments while passing through the spinneret may pass through a coagulation bath having a coagulating solution temperature of 10 to 30°C. While maintaining the temperature of the coagulation solution in the above range, it is possible to improve the spinnability and control the physical properties by giving an appropriate draw ratio of the discharged fibers.

Step S3

Step S3 is a step of washing the solidified lyocell filament. In the water washing step, the Lyocell filament obtained in the step S2 may be introduced into the water washing bath 15 to be washed with water. If necessary, the coagulated lyocell filament may be introduced into the washing bath through a pulling roller (not shown). In step S3, in consideration of the possibility of recovery and reuse of the solvent after washing with water, a washing solution having a temperature of 10° C. to 100° C. may be used. The washing liquid may be water, and other functional ingredients may be added to the water as needed.

Step S4

The step of treating the emulsion on the washed filament is step S4. The emulsion treatment step generally serves to reduce friction when the filament comes into contact with a drying roller and a guide in the post-processing process. The method of treating the emulsion may be, for example, such that the washed filaments are completely immersed in the emulsion solution as schematically indicated by reference numeral 16 of FIG. 1 to apply the emulsion to the filaments. It is also necessary to process the emulsion to be uniformly applied to the filament, which is a method of controlling the pressure difference between the entry roll that allows the filament to enter the emulsion bath 16 and the release roll that discharges the filament from the emulsion bath to the drying step. can be achieved with

crosslinking agent

The crosslinking agent for reducing the fibrillation of the lyocell filaments may be made simultaneously with the treatment of the emulsion in step S4. This can be achieved by adding a crosslinking agent to the emulsion bath 16 . That is, the oil agent and the crosslinking agent are simultaneously treated on the filament by making the oil agent solution contain both the oil agent and the crosslinking agent. Since the treatment of the oil agent and the crosslinking agent are simultaneously processed on the filament, it is preferable to appropriately control the amount of the crosslinking agent added together with the oil agent in order to maximize the fibrillation reduction effect. may be 0.001% to 5.0%.

In one embodiment of the present invention, the crosslinking agent that can be used may be represented by the following formula (1).

[Formula 1]

In the above formula, R1, R2 and R3 are each independently the same or different functional groups R-N=C=O, wherein R is each independently an alkyl group, alkenyl group, alkynyl group, or aryl group having 2 to 20 carbon atoms.

Since the oil agent component to be treated on the Lyocell filament is usually aqueous, a functional group that is a reaction point where the crosslinking agent cross-reacts with cellulose may react with water. In this case, since the addition of the crosslinking agent may not achieve the original purpose, the crosslinking agent present together with the oil agent in the oil agent bath may be appropriately treated so as not to react with the water component of the oil agent. The treatment may include treatment with an end capping reagent so that the functional group at the reaction site does not react with water.

The cross-linking agent treated with the end-capping reagent may form a cross-link with the hydroxyl group in the cellulose molecule of the Lyocell fiber in the following drying step (S5). The drying step may be carried out in a drying chamber of usually 80 to 170° C., and a temperature at which the end-capping agent is released from the functional group and the functional group can react with the hydroxyl group can be achieved at the drying temperature. For example, when dimethyl pyrazzole (DMP) is used as an end-capping agent to end-capping an isocyanate group, the functional group of the end-capped cross-linking agent may be restored to an isocyanate group at about 120°C. The isocyanate group of the restored crosslinking agent reacts with a hydroxyl group in the cellulose molecule of the Lyocell filament to form a crosslink, thereby eliminating the cause of fibrillation.

The crosslinking agent may include two or more functional groups reacting with a hydroxyl group in the cellulose molecule, and the functional group may be an isocyanate group.

The crosslinking agent that can be preferably used in one embodiment of the present invention may include an HDI isocyanurate trimer including an isocyanate group as a functional group.

[HDI isocyanurate trimer]

The isocyanate group of the HDI isocyanurate trimer reacts with the hydroxyl group of cellulose to form a strong urethane bond.

Because the urethane bond reaction rate is fast, the HDI isocyanurate trimer can be used as a preferred crosslinking agent.

In one embodiment of the present invention, when HDI isocyanurate trimer is used as a crosslinking agent and dimethyl pyrazole (DMP) is used as an end capping agent, the isocyanate group of HDI isocyanurate trimer is bonded to DMP to reduce fibrillation of lyocell fibers by crosslinking with hydroxyl groups in the cellulose molecules of lyocell fibers as they are included in the emulsion bath together with the emulsion in an inactivated state, and the capped isocyanate groups are restored through a drying step prepared at 120°C can do.

Step S5

Step S5 is a step of drying the lyocell filament treated with an emulsion and a crosslinking agent. The drying step may be performed in the drying chamber 17 at 80 to 170° C., and may be performed at 110 to 140° C. for at least 40 seconds in terms of maintaining the moisture content of the filament at a level of 8% to 10%.

Hereinafter, preferred examples are presented to help the understanding of the present invention, but the following examples are only illustrative of the present invention and the scope of the present invention is not limited to the following examples.

According to another embodiment of the present invention, there is provided a method for producing a lyocell staple fiber. Staple refers to a length cut from a natural fiber or filament. Staple fibers refer to short fibers of 20 mm to 200 mm level, and general natural fibers except silk exist in the form of staple fibers and are used directly or manufactured as spun yarn depending on the purpose.

Man-made fibers can be processed into filaments, and they are also cut and processed into staple fibers. Lyocell staple fiber according to an embodiment of the present invention can be prepared by cutting the lyocell filament prepared by performing the steps S1 to S5.

In another embodiment of the present invention, lyocell staple fibers may be prepared by a method comprising the steps described below:

(a) spinning dope for lyocell production through a spinneret;

(b) passing the spun dope through a coagulation bath to solidify into filaments;

(c) cutting the filament obtained in step (b) to obtain a short fiber;

(d) washing the short fibers with water;

(e) treating the short fibers with an oil agent and a crosslinking agent; and

(f) drying the short fibers treated with the oil agent and the crosslinking agent.

Step (a) in the above manufacturing method is not different from the method for manufacturing a filament. The dope for lyocell production includes NMMO aqueous solution as a solvent component and pulp capable of supplying cellulose. The pulp is not particularly limited as long as it is a source of cellulose and may be derived from waste paper, wood, and the like. In order to reduce fibrillation through raw materials, linter pulp with a short fiber length separated from cotton may be used, and bamboo pulp extracted from bamboo may also be used.

The dope for spinning may include an aqueous NMMO solution at a level of 60 to 94% by weight as a solvent component. If the content of the NMMO aqueous solution is less than 84% by weight, the dissolution viscosity may be greatly increased, and if it exceeds 94% by weight, the spinning temperature is excessively high, which is disadvantageous because decomposition of NMMO may occur.

The spinneret serves to allow the spinning dope to pass through and form a fibrous filament, and the formed filament is discharged as a coagulating solution through the air gap. The process of discharging the dope for spinning from the spinneret may be performed at 80° C. to 130° C.

The step (b) is a step of coagulating the dope to be spun into a filament by passing it through for coagulation. The spinning dope formed into filaments while passing through the spinneret may pass through a coagulation bath having a coagulating solution temperature of 10° C. to 30° C. While maintaining the temperature of the coagulating solution in the above range, it is possible to improve the spinning shape and control the physical properties by giving an appropriate draw ratio to the discharged fibers.

Step (c) is a step of obtaining short fibers by cutting the filament obtained in step (b). The filament discharged in step (b) may be wound on a bobbin or the like before being cut into short fibers, and a crimp may be formed. Regardless of the presence or absence of the winding process, the cutting of the filament may be cut using a rotary cutter or the like, and the method of cutting the filament will be clearly understood by those skilled in the art. The cut length may vary depending on the composition and end use of the fibers, and in general, short fibers for cotton textile applications may have a length of 20 mm to 80 mm.

Steps (d) and (e) are steps for washing the short fibers obtained in step (c) with water and treating an oil agent and a crosslinking agent. In one embodiment of the present invention, steps (d) and (e) may be performed in such a way that step (e) is performed after step (d), or may be performed simultaneously. If step (d) is performed first, it can be washed with the cut short fibers introduced into the washing bath. The washing liquid may be water having a temperature of 10°C to 100°C, and other functional ingredients may be added as necessary.

Short fibers may then be introduced into the emulsion bath for the emulsion treatment. When the oil agent is treated, the oil agent treatment and the crosslinking agent treatment can be performed together by adding the oil agent and the crosslinking agent to the oil agent bath. The crosslinking agent used in this case may be represented by the following Chemical Formula 1.

[Formula 1]

In the above formula, R1, R2 and R3 are each independently the same or different functional groups R-N=C=O, wherein R is each independently an alkyl group, alkenyl group, alkynyl group, or aryl group having 2 to 20 carbon atoms.

Since the oil agent component to be treated on the Lyocell filament is usually aqueous, a functional group that is a reaction point where the crosslinking agent cross-reacts with cellulose may react with water. In this case, since the addition of the crosslinking agent may not achieve the original purpose, the crosslinking agent present together with the oil agent in the oil agent bath may be appropriately treated so as not to react with the water component of the oil agent. The treatment may include treatment with an end capping reagent so that the functional group at the reaction site does not react with water.

The cross-linking agent treated with the end-capping reagent may form a cross-link with the hydroxyl group in the cellulose molecule of the Lyocell fiber in the following drying step (S5). The drying step may be carried out in a drying chamber of usually 80 to 170° C., and a temperature at which the end-capping agent is released from the functional group and the functional group can react with the hydroxyl group can be achieved at the drying temperature. For example, when dimethyl pyrazzole (DMP) is used as an end-capping agent to end-capping an isocyanate group, the functional group of the end-capped cross-linking agent may be restored to an isocyanate group at about 120°C. The isocyanate group of the restored crosslinking agent reacts with a hydroxyl group in the cellulose molecule of the Lyocell filament to form a crosslink, thereby eliminating the cause of fibrillation.

The crosslinking agent may include two or more functional groups reacting with a hydroxyl group in the cellulose molecule, and the functional group may be an isocyanate group.

The crosslinking agent that can be preferably used in one embodiment of the present invention may include an HDI isocyanurate trimer including an isocyanate group as a functional group.

The isocyanate group of the HDI isocyanurate trimer reacts with the hydroxyl group of cellulose to form a strong urethane bond.

Because the urethane bond reaction rate is fast, the HDI isocyanurate trimer can be used as a preferred crosslinking agent.

In one embodiment of the present invention, when HDI isocyanurate trimer is used as a crosslinking agent and dimethyl pyrazole (DMP) is used as an end capping agent, the isocyanate group of HDI isocyanurate trimer is bonded to DMP to reduce fibrillation of lyocell fibers by crosslinking with hydroxyl groups in the cellulose molecules of lyocell fibers as they are included in the emulsion bath together with the emulsion in an inactivated state, and the capped isocyanate groups are restored through a drying step prepared at 120°C can do.

Step (f) is a step of drying the short lyocell fibers treated with an oil agent and a crosslinking agent. The drying step may be performed by a conventional method for producing staple fibers, and the temperature and time may be adjusted in consideration of the moisture content of the final obtained staple fibers.

Hereinafter, preferred examples are presented to help the understanding of the present invention, but the following examples are only illustrative of the present invention and the scope of the present invention is not limited to the following examples.

Example

A softwood pulp sheet (GP, polymerization degree (DP) 800) was put into a grinder equipped with a 100 mesh filter to prepare a pulp powder having a length of 1700 μm or less. The pulp powder was swollen in 50% by weight aqueous NMMO solution. At this time, the content of the pulp in the NMMO aqueous solution was 6% by weight, and the antioxidant was added in an amount of 0.01% by weight.

While injecting the swollen pulp slurry into a kneader with an internal temperature of 90° C. and an absolute pressure of 50 mmHg at a rate of 16 kg/hour with a rotary valve pump, 50% by weight of the NMMO aqueous solution is 89% by weight of the NMMO aqueous solution. After completely dissolving the pulp while removing moisture, the spinning stock solution was discharged through the discharge screw.

The dope for preparing lyocell was prepared by spinning, coagulation, washing with water, emulsion treatment and drying using a spinning apparatus based on the configuration as shown in FIG. 1 to prepare lyocell filament fibers.

The dope for preparing the lyocell was adjusted to have a final filament total fineness of 60,000 denier, and the number of nozzles was 40,000, and was spun using a nozzle having a nozzle diameter of 0.1 mm. At this time, an air layer of 40 mm was placed between the spinning nozzle and the coagulation bath, and cooling air at 10° C. was supplied to the dope discharged at an air volume of 1,500 m ³ /hr.

After passing through the air gap, the multifilaments coagulated in the first coagulation bath and the second coagulation bath were washed with water in an 8-stage washing equipment, and then the washed filaments were passed through an emulsion bath containing a crosslinking agent. .

In the emulsion bath, the washed filaments were immersed in an emulsion and a crosslinking agent. HDI isocyanurate trimer was used as the crosslinking agent, and the crosslinking agent was in a state in which an isocyanate group was capped with dimethylpyrazole, which was treated with an emulsion on a Lyocell filament.

The Lyocell filaments treated with the emulsion and the crosslinking agent were dried in an atmosphere of 120° C. for 60 seconds so that the moisture content of the Lyocell filaments was about 9%.

comparative example

After passing the lyocell filament treated with spinning, coagulation and water washing under the same conditions as in the above example through an oil bath that does not contain a crosslinking agent, the lyocell filament treated with only the emulsion was dried in an atmosphere of 120° C. for 60 seconds. of the moisture content was about 9%.

Experimental Example - Measurement of fibrillation degree

After cutting the lyocell filament to 2mm length and collecting 0.02g, put it in a 5ml cylinder, and add 2.2ml of sodium hydroxide (NaOH). Seal the cylinder and mix for 15 minutes at a frequency of 30 Hz using a shaker to induce friction between lyocell filaments to induce fibrils.

After the friction-treated lyocell filament is collected and spread on a glass plate, the fibrillation degree (Fibril Index, FI) is evaluated using an optical microscope.

The degree of fibrillation is expressed in grades, and the degree of fibrillation is indicated by dividing the fibrillation degree into sections of 5 to 9 grades according to the number of fibrils per unit length (usually 0.1 mm).

Fibrils were generated in each of the Lyocell filaments treated with the crosslinking agent prepared in Examples and the Lyocell filaments prepared in Comparative Examples by the method of the Experimental Example. 3 shows an optical micrograph of the Lyocell filament of the Example treated with the crosslinking agent after the experiment, and FIG. 4 shows an optical micrograph that can determine the fibril generation degree of the Lyocell filament of the Comparative Example after the experiment. Comparing the two optical micrographs, it can be seen that the fibrillation degree of the lyocell fiber according to the embodiment of the present invention is very low.

Since the lyocell fiber produced by the manufacturing method of the present invention has a low degree of fibrillation, it has excellent post-processing properties such as weaving and dyeing, and can be used for various purposes such as clothing and mask packs.

11: Spinneret (nozzle)
12: uncoagulated fiber
13: first coagulation bath
14: second coagulation bath
15: water bath
16: oil bath
17: drying chamber
101: drug bath
201: steaming chamber

Claims (11)

delete delete delete delete delete delete delete Spinning a dope for lyocell production through a spinneret;
passing the spun dope through a coagulation bath to solidify into filaments;
washing the filaments that have passed through the coagulation bath;
treating the washed filament with an emulsion and a crosslinking agent; and
In the lyocell manufacturing method comprising the step of drying the filament treated with the emulsion and the crosslinking agent at a drying temperature of 80 ℃ to 170 ℃,
The emulsion is aqueous,
The cross-linking agent is a material represented by the following formula (1), the functional group of the cross-linking agent present together with the oil agent will be treated with an end-capping reagent, a method for producing a lyocell fiber:
[Formula 1]

(R1, R2 and R3 are each independently the same or different functional groups RN=C=O, wherein R is each independently an alkyl group, alkenyl group, alkynyl group, or aryl group having 2 to 20 carbon atoms). delete The method of claim 8, wherein the end-capping reagent is dimethylpyrazole. The method of claim 10, wherein the drying temperature is 120°C.

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