KR20190081702A - Non-woven Fiber aggregates containing Lyocell Fibers - Google Patents

Abstract

The present invention relates to a nonwoven fiber aggregate comprising lyocell fibers. The present invention provides the nonwoven fiber aggregate comprising lyocell fibers whose cross section of a monofilament is a flat yarn or a flat yarn having curvature, thereby being able to exhibit physical properties that could not be provided in lyocell fibers. Therefore, it is possible to provide an effect of having excellent bending properties for industrial material uses, good texture and soft gloss properties for clothing and interior application uses, and transparency, skin adhesion, solvent absorbency such as moisture, retention, smooth surface feel and the like for mask pack nonwoven fabric aggregate uses.

Description

[0001] Description [0002] Non-woven fiber aggregates containing Lyocell fibers [

The present invention relates to nonwoven fibrous assemblies comprising lyocell fibers.

Fiber means a natural or artificial linear object that is flexible and thin when viewed in shape and has a large length to thickness ratio. These fibers are divided into long fibers, quasi-long fibers, and short fibers. The fibers are divided into natural fibers and man-made fibers.

Previously, fibers had a close relationship with human life, and natural fibers such as cotton, hemp, wool, and silk fiber were used as the main raw materials for the fabrics. Since the industrial revolution, the textile has expanded its application not only to the covering materials but also to the industrial use. In order to meet the rapidly increasing demand of the fiber with the development of the culture and the population, It was pioneered.

Among these man-made fibers, regenerated fibers are not only excellent in feel and fit, but also have moisture absorbing and discharging ability much faster than cotton, and thus they have been widely used as raw materials for coating. Particularly, among these regenerated fibers, rayon fibers have excellent gloss and coloring property and can not only realize a feeling equivalent to that of natural fibers but also have been widely used in the past as they are recognized as harmless materials to human body. However, these rayon fibers have characteristics of shrinkage and creasing. Since the manufacturing process is complicated and a lot of chemicals are used in the process of melting wood pulp and the like, environmental pollution And the like.

As a result, research has been conducted on fibers that are harmless to the environment and human body and have superior physical properties and superior to other conventional fibers. Recently, Lyocell fibers produced from natural pulp and amine oxide hydrates have been introduced. These lyocell fibers have excellent tensile properties and tactile properties as compared with conventional regenerated fibers, and do not generate any contaminants in the production process. The amine oxide-based solvent used is recyclable and biodegradable upon disposal , And are used in various fields as environmentally friendly fibers.

However, it is expected that the present lyocell fiber can be produced only in the form of a circular cross-section, and it is expected that it will exhibit various physical properties depending on the cross-sectional shape of the lyocell fiber. .

The present invention provides a nonwoven fabric assembly comprising a monofilament having a flat cross section or a flat yarn having a curvature and having lyocell fibers. The monofilament has excellent bending properties for industrial applications, good texture and soft gloss for clothing and interior applications, The use of a mask pack nonwoven fabric aggregate can provide an effect having excellent physical properties such as transparency, skin adhesion, solvent absorbency and retention of water such as moisture, and smooth surface touch.

The present invention relates to a nonwoven fabric assembly comprising a lyocell fiber, wherein the monofilament constituting the lyocell fiber has a cross section having a central longitudinal axis (L1) and a central minor axis (S1) Wherein a ratio of a length of the major axis L1 to a minor axis S1 is 1.5: 1 to 10.5: 1 and a ratio of a length of the center long axis L1 to a length of a straight line L2 at both ends of the center long axis is 1.0 to 1.5 : 1. ≪ / RTI >

In this embodiment, the length of the center long axis L1 of the monofilament may be 12 to 42 mu m, and the length of the center short axis S1 may be 4 to 7 mu m.

In the above embodiment, the monofilament may have a fineness of 1.0 to 4.0 denier, and a value obtained by dividing the peripheral length of the monofilament by the fineness may be 24.5 to 32 μm / denier.

In this embodiment, the fineness of the lyocell fiber may be 1.0 to 4.0 denier.

In this embodiment, the fiber length of the lyocell fiber may be 36 to 40 mm.

In this embodiment, the number of crimps of the lyocell fibers may be between 8 and 12 cpi.

In this embodiment, the content of the emulsion of the lyocell fiber may be 0.1 to 0.4% by weight based on 100% by weight of the lyocell fiber.

In this embodiment, the basis weight of the nonwoven fibrous aggregate may be 30 to 60 g / m ² .

In this embodiment, the thickness of the nonwoven fabric aggregate may be 0.3 to 0.5 mm.

In this embodiment, the nonwoven fibrous aggregate may have a water absorption rate of 1000 to 1600% based on the weight of the lyocell fiber.

In this embodiment, the nonwoven fibrous aggregate may have a transparency of 80 to 84% after the water treatment.

In this embodiment, the nonwoven fabric aggregate may have a transparency of 88 to 94% after the essence treatment.

In this embodiment, the nonwoven fibrous aggregate may have a skin adhesion of 3.6 to 4.2 gf after the water treatment.

In this embodiment, the nonwoven fibrous aggregate may have a skin adhesion of 4.5 to 5.3 gf after the essence treatment.

In this embodiment, the nonwoven fabric aggregate may have an emulsion content of 0.001% by weight or less based on 100% by weight of the nonwoven fabric aggregate.

According to another aspect of the present invention, there is provided a mask pack sheet using the above-described nonwoven fabric assembly.

The present invention can exhibit physical properties that could not be provided by existing circular cross-section lyocell fibers by providing a nonwoven fibrous aggregate comprising lyocell fibers that are flattened in cross section of monofilaments or have a curvature with a curvature , Excellent bending properties for industrial materials, good feel and soft gloss for clothing and interior applications, and excellent physical properties such as transparency, skin adhesion, solvent absorption and retention such as moisture, and smooth surface feel Effect can be provided.

FIG. 1 is a schematic cross-sectional view of a monofilament included in a lyocell fiber according to an embodiment of the present invention.
2 is a photograph showing a cross section of a lyocell fiber produced according to an embodiment of the present invention.

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

The present invention relates to a lyocell multifilament prepared by spinning a lyocell radial dope comprising a cellulose pulp and a solvent, wherein the monofilament constituting the multifilament has a cross section having a center long axis (L1) and a center short axis (S1) Wherein a ratio of a length of the center long axis L1 to a center short axis S1 is 1.5: 1 to 10.5: 1, and a length of the center long axis L1 and a length of a straight line L2 of both ends of the center long axis L1 Is in the range of 1.0: 1 to 1.5: 1.

The lyocell fiber of the present invention comprises a monofilament having a flat cross section, the cross section of which is shown in Fig.

That is, the length of the center long axis L1 is at least 1.5 times longer than the length of the center short axis S1, and is at most 10.5 times shorter than the length of the center short axis S1, so that the cross section becomes flat with a flat shape. And the length of the straight line L2 at both ends of the central longitudinal axis is 1: 1, the straight line becomes flat. If the ratio exceeds 1: 1, the straight line having a curvature becomes a flat yarn will be.

As described above, since the cross section of the monofilament is flat or curved and flattened, it is possible to exhibit the physical characteristics that the conventional circular cross-section of the lyocell fiber could not exhibit. In particular, excellent bending It is possible to exhibit excellent physical properties such as transparency, skin adhesion, water absorption and retention of solvent such as moisture, smooth surface touch, and the like, for the characteristics, the clothing and the interior use, the good feel and the smooth gloss property, and the mask pack nonwoven fabric aggregate.

The length ratio between the center major axis L1 and the center minor axis S1 should satisfy a range of 1.5: 1 to 10.5: 1, with a center major axis L1 and a center minor axis S1, , There is a disadvantage in that it is difficult to exhibit properties significantly different from those of the circular cross-section yarns, and when the ratio exceeds 10.5: 1, the fineness of the desired final fiber can not be matched will be.

The ratio of the length of the center long axis L1 to the length of the straight line L2 at both ends of the center long axis is 1.0: 1 to 1.5: 1, preferably 1.1: 1 to 1.5: 1 Lt; / RTI > If the ratio of the curvature exceeds 1.5: 1, the curvature becomes excessively large, which causes a reduction in the interfiber adhesion, which reduces the effect of the flat yarn.

The monofilament of the present invention is characterized in that the length of the center long axis L1 is 12 to 42 mu m and the length of the center short axis S1 is 4 to 7 mu m, The range of fiber production is within the fineness range of 1.0 to 4.0 denier.

In other words, if the length of the center short axis S1 is less than 4 mu m, it is difficult to realize due to the limitations of the fabrication processing technique. If the length L1 of the center long axis exceeds 42 mu m, It is not meaningful. When the length of the center short axis S1 is more than 7 mu m and the length of the center long axis L1 is less than 12 mu m, the specific surface area may be lowered and the interfiber adhesion may be deteriorated.

The monofilament of the present invention has a fineness of 1.0 to 4.0 denier and a value obtained by dividing the peripheral length of the monofilament by the fineness of 22 占 퐉 / denier or more, preferably 24.5 to 32 占 퐉 / denier, The monofilament itself has an increased specific surface area, and when applied to a product, it can be applied to an effective field. For example, in the mask pack nonwoven fabric aggregate, the absorbency and retention It is possible to have an advantage.

As described above, the lyocell fibers as described above are biodegradable, and thus environmentally friendly. Further, the lyocell fibers of the present invention show a monofilament having a straight flat cross section or a curved flat cross section, Compared to the cross section, the bending property to withstand the external force becomes strong, and the fiber strand becomes a mirror-like mirror-like reflection, so that the surface is shiny and shiny. In addition, the tactile feeling can be applied to various fields such as a car seat cover, a car seat cover, a carpet, a curtain, various industrial materials such as a garment, and a garment use, because of a special section effect.

In particular, when the lyocell fiber according to the present invention is produced in the form of a staple fiber and used as a nonwoven fabric aggregate for a mask pack, the most important physical properties of the nonwoven fabric aggregate for a mask pack are transparency, skin adhesion force, essence absorption power, It has the effect of showing very good physical properties compared to other materials.

When the fiber cross-section is flat, the thickness of the fiber becomes small, and when the nonwoven fiber aggregate is manufactured, the thickness of the nonwoven fiber aggregate becomes thinner than that of a general circular cross-sectional fiber at the same unit weight. Therefore, dipping in cosmetics such as essence becomes transparent, It has very good features.

In addition, since the specific surface area is larger than that of the circular cross-section fibers having the same fineness, the essence holding power is also advantageous because the absorbency to the solvent such as essence is high, which is a great advantage compared to other materials applied to the mask pack nonwoven fibrous aggregate.

When the lyocell fiber according to the present invention is used as a nonwoven fabric aggregate sheet for a mask pack, the fineness may be 1.0 to 4.0 denier. At this time, when the fineness of the lyocell fiber is less than 1.0 denier, the production of the lyocell fiber becomes difficult. When the lyocell fiber exceeds 4.0 denier, since it is more than the general fineness applied to the mask pack, There is no difference in characteristics, and physical properties show a general level

The lyocell fiber may have a fiber length of 36 to 40 mm. When the lyocell fiber is used as a nonwoven fabric aggregate for a mask pack within the fiber length range, there is an advantage in that the processability during the carding process during the production of the nonwoven fabric aggregate is excellent.

In addition, the number of crimps of the lyocell fibers may be between 8 and 12 cpi. The crimp number may be 5 to 20 cpi, preferably 8 to 12 cpi. If the number of crimps is less than 5 cpi, the entanglement of the fibers in the carding process is low during the manufacturing process of the nonwoven fabric aggregate, resulting in a process problem. If the number of crimps exceeds 20 cpi, the crimp number is too large, A problem arises.

The lyocell fiber may have an emulsion content of 0.1 to 0.4% by weight based on 100% by weight of the lyocell fiber. When the emulsion satisfies the weight percentage range, it reduces the friction generated during the process of forming the filament to be crimped to be described later, and forms a fiber-to-fiber crimp. Also, the carding property of the nonwoven fabric aggregate is improved.

The basis weight of the nonwoven fibrous aggregate may be 30 to 60 g / m ² , and the thickness may be 0.3 to 0.5 mm. The basis weight and the thickness range are set to an optimum range for improving the water absorption, transparency, and adhesion of the liquid composition in the nonwoven fabric aggregate comprising the lyocell fibers satisfying the fineness, fiber length, crimp water and emulsion content of the lyocell fiber .

In addition, the nonwoven fabric aggregate may have a moisture absorption rate of 1000 to 1600% based on the weight of the lyocell fiber. As described above, the lyocell fiber is hydrophilic and has higher water absorption than other fibers. However, when the basis weight and thickness range of the nonwoven fabric aggregate are satisfied while satisfying the characteristics of the lyocell fiber, The water absorption rate of the nonwoven fabric aggregate can be adjusted to the above range.

The transparency of the nonwoven fabric aggregate may be 80 to 84% after the moisture treatment, and the transparency after the essence treatment may be 88 to 94% before the essence treatment. The transparency of the nonwoven fabric aggregate corresponds to the fineness of the lyocell fiber of 1.0 to 4.0 denier, and the thickness of the nonwoven fabric aggregate including the lyocell fiber is thinner than that of a conventional one. Therefore, the liquid composition such as moisture, When the nonwoven fabric is supported on the nonwoven fabric aggregate, the nonwoven fabric aggregate can have a soft feeling and transparency within the range of the transparency.

In addition, the nonwoven fabric aggregate may have a skin adhesion force of 3.6 to 4.2 gf after the water treatment and a skin adhesion force of 4.5 to 5.3 gf after the essence treatment. The skin adhesion of the nonwoven fabric aggregate also satisfies the characteristics of the lyocell fiber, and the above range can be satisfied by the basis weight and thickness of the nonwoven fabric aggregate containing the same.

The nonwoven fabric aggregate has an emulsion content of 0.001% by weight or less based on 100% by weight of the nonwoven fabric aggregate. The nonwoven fabric aggregate exhibits the above-mentioned contents because most of the emulsion contained in the lyocell fiber is washed away when the spun lace process is intermingled during the nonwoven fabric manufacturing process.

Hereinafter, the nonwoven fabric aggregate containing the lyocell fibers will be described in detail through a method for producing the nonwoven fabric aggregate.

The present invention relates to (S1) radiating a lyocell radial dope comprising a cellulose pulp and a solvent; (S2) solidifying the lyocell radiation dope radiated in the step (S1) to obtain a lyocell multifilament; (S3) washing the lyocell multifilament obtained in the step (S2); And (S4) emulsifying the lyocell multifilament washed in the step (S3). (S5) crimping the tanned lyocell multifilament in a stuffer box to obtain a crimped tow; (S6) drying and cutting the crimped tow obtained in the step (S5) to obtain lyocell staple fibers; And (S7) fabricating the lyocell staple fiber obtained in the step (S6) as a nonwoven fabric assembly, wherein the monofilament constituting the multifilament has a cross-section of a center long axis (L1) and a center short axis (S1), wherein a ratio of a length of the central longitudinal axis (L1) to a center minor axis (S1) is 1.5: 1 to 10.5: 1, And the length of the straight line (L2) at both ends is 1.0: 1 to 1.5: 1.

The lyocell fiber of the present invention can be prepared by dissolving a cellulose pulp in a solvent to prepare a lyocell spinning dope and then spinning the spinning dope to prepare a lyocell fiber. (NMMO) aqueous solution or an ionic solvent. Hereinafter, a method for producing the lyocell fiber of the present invention using an aqueous solution of NMMO Will be described in detail.

[Step (S1)] [

(S1) is a step of radiating a lyocell spinning dope comprising cellulose pulp and an NMMO aqueous solution.

The lyocell spinning dope comprises 6 to 16% by weight of cellulose pulp; And 84 to 94% by weight of an aqueous solution of N-methylmorpholine-N-oxide, wherein the cellulose pulp has an alpha-cellulose content of 85 to 97% by weight and a degree of polymerization (DPw) of 600 to 1700 have.

If the content of the cellulose pulp in the lyocell radial dope is less than 6% by weight, it is difficult to realize the fiber property. If the content is more than 16% by weight, it may be difficult to dissolve in the aqueous liquid.

If the content of the aqueous solution of N-methylmorpholine-N-oxide in the lyocell radial dope is less than 84% by weight, the solubility of the solution is undesirably large, and if it exceeds 94% by weight, It may be difficult to produce a uniform fiber.

The weight ratio of N-methylmorpholine-N-oxide and water in the N-methylmorpholine-N-oxide aqueous solution may be 93: 7 to 85:15. When the weight ratio of N-methylmorpholine-N-oxide and water is more than 93: 7, the dissolution temperature is high and the cellulose may be decomposed upon dissolving cellulose. When the weight ratio is less than 85:15, And the dissolution of cellulose may be difficult.

The above-described radiation dope is used to discharge it from the spinneret of the spinneret. At this time, the spinneret serves to discharge the spinning dope on the filament as a coagulating solution in the coagulation bath through the air gap section.

The spinneret may have a slit-shaped hole formed in a long and flat shape with a cantilever shape bent in a C-shape.

It is also important that the arresting of detention holes be very important and that all holes may be in contact with the cooling air during air quenching and should not interfere with each other.

The step of discharging the spinning dope from the spinneret can be performed at a spinning temperature of 80 to 130 캜.

[Step S2]

(S2) is a step of solidifying the lyocell radiation dope radiated in the step (S1) to obtain a lyocell multifilament, wherein the solidification in the step (S2) is performed by air quenching (Q / A); And a secondary coagulation step in which the primary coagulated radial dope is immersed in the coagulating liquid to coagulate.

In the step (S1), after the spinning dope is discharged through the spinneret, it can be passed through the air gap section of the space between the spinneret and the coagulation bath. In such an air gap section, cooling air is supplied from the air cooling part located inside the detachment of the donut type to the outside from the inside of the detent, which can be primary solidified by air quenching which supplies the cooling air to the radiation dope.

At this time, the factor affecting the physical properties of the lyocell multifilament obtained in the step (S2) is the temperature and the wind speed of the cooling air in the air gap section, and the solidification in the step (S2) The cooling air having a wind speed of 10 m / s may be supplied to the spinning dope to solidify.

If the temperature of the cooling air during the primary solidification is less than 4 캜, the surface of the spinneret cools, the cross-section of the lyocell multifilament becomes uneven and the spinning processability becomes poor. If the temperature is more than 15 캜, The radiation fairness becomes poor.

In addition, the flat yarn is very sensitive to the air quenching velocity during spinning. If the air velocity of the cooling air during the first solidification is less than 5 m / s, the primary coagulation due to the cooling air is not sufficient, If it is more than 10m / s, the radial dope discharged from the cage is flattened, so that the length of the center short axis is shortened, and it is shaken by air quenching,

After primary coagulation by air quenching, the spinning dope is supplied to the coagulation bath containing the coagulation solution and secondary coagulation can proceed. On the other hand, the temperature of the coagulating solution may be 30 DEG C or less for the progress of proper secondary coagulation. This is so that the secondary solidification temperature is not higher than necessary, so that the solidification rate is properly maintained. Herein, the coagulating solution is not particularly limited as it can be manufactured and used in a conventional composition in the technical field to which the present invention belongs.

[Step (S3)] [

(S3) is washing the lyocell multifilament obtained in the step (S2).

Specifically, the lyocell multifilament obtained in the step (S2) may be introduced into a traction roller and then introduced into a water bath to be washed with water.

In the washing step of the filament, a washing solution at a temperature of 0 to 100 ° C may be used in consideration of the ease of recovery and reuse of the solvent after washing with water. Water can be used as the washing solution, May be further included.

[Step (S4)] [

(S4) is a step of tanning the lyocell multifilament washed in the step (S3), and may be dried after emulsion treatment.

The tanning process takes the form that the multifilament is buried as it passes over the surface of the roller bearing the tanning agent and adjusts the amount of tanning agent applied to the filament by the speed of the tanning roller. The emulsions reduce the friction that occurs when the filaments contact dry rollers and guides, coiling or crimping, and allow the crimp to form well.

[Step (S5)] [

(S5) is a step of obtaining a crimped tow by crimping the lyocell multifilament treated by tanning in the step (S4).

Crimping is a process of applying a crimp to a multifilament, specifically crimping with a stuffer box to obtain a crimped tow having 8 to 12 crimps per inch.

In step (S5), steam may be supplied to the lyocell multifilament and crimped by applying pressure.

Specifically, by passing the lyocell multifilament in a steam box (Steam box), the steam is 0.1 ~ 1.0kgf / cm ² and supplied to raise the temperature, and then 1.5 to pressure by the press roller (Press Roller of 3.0kgf / cm ² ), Thereby forming a crimp in the stopper box.

At this time, if the supply amount of steam is less than 0.1 kgf / cm ^{2, the} crimp can not be smoothly formed. If the supply amount of steam is more than 1.0 kgf / cm ^2, the temperature in the stopper box rises to 120 ° C or more, and the filaments stick together and can not pass through the stopper box. Further, by pressing the pressure roller, without pressure is not desired crimp is not formed is less than 1.5 kgf / cm ^2, which, 3.0kgf / cm ² The pressing force is too strong so that the filament may not pass through the stopper box.

[Step S6]

(S6) is a step of drying and cutting the crimped tow obtained in the step (S5) to obtain a lyocell staple fiber.

The crimped tow is dried using a Lattice drier and subjected to a cutting process to form a lyocell staple fiber.

[Step S7]

(S7) is a step of preparing the lyocell staple fibers obtained in the step (S6) into a nonwoven fabric aggregate.

The lyocell staple fibers are received and entangled by carding and spun racing to produce a nonwoven fabric assembly.

The present invention can be used as a cosmetic mask pack using the mask pack sheet. Using the mask pack sheet as a support sheet, the mask pack not only improves the skin adhesion and comfort in the face portion having many bends, but also absorbs liquid compositions such as moisture and essence, .

In addition, when the wet transparency is improved and is brought into close contact with the user's face, the appearance of the user's face may be made to be close to that of the user's face.

[ Example ]

Hereinafter, the present invention will be described in more detail with reference to Examples. It is to be understood by those skilled in the art that these embodiments are only for describing the present invention in more detail and that the scope of the present invention is not limited by these embodiments.

<Experimental Example 1>

Example 1

A cellulose pulp having a degree of polymerization (DPw) of 820 and an alpha-cellulose content of 93.9% was mixed with an NMMO / H ₂ O mixed solvent (weight ratio 90/10) having a propyl gallate content of 0.01% by weight to prepare a lyocell fiber Dope.

First, the spinning dope was maintained at a spinning temperature of 110 캜 in a spinneret of a spinneret having a plurality of flat slit-shaped unit holes having a curvature, and the discharge amount of the spinning dope was adjusted to be 2.0 denier The emission rate was adjusted to emit. The spinning dope on the filament discharged from the spinning nozzle was supplied to the coagulating solution in the coagulation bath through the air gap section. At this time, the cooling air in the air gap section is subjected to primary solidification of the spinning dope at a temperature of 8 캜 and a wind speed of 57 m / s.

The coagulating solution used was a solution having a temperature of 25 ° C and a concentration of 85% by weight of water and 15% by weight of NMMO.

The filaments drawn in the air layer through the traction roller were washed with a wash water sprayed in a water washing device to remove the remaining NMMO and the emulsion was uniformly applied to the filaments so that the emulsion content was maintained at 0.2% And dried at 150 캜 to prepare a lyocell fiber including multifilaments composed of monofilaments having a curvilinear flat section.

Example 2

A lyocell fiber including a multifilament made of a monofilament having a curved flattened cross section was prepared in the same manner as in Example 1, except that the monofilament had a fineness of 1.6 denier.

Example 3

A lyocell fiber including a multifilament made of a monofilament having a curvilinear flat section was prepared in the same manner as in Example 1, except that the monofilament had a fineness of 2.4 denier.

Comparative Example 1

The same procedure as in Example 1 was carried out except that one circular hole was used as a unit hole and a spinneret having a plurality of unit holes was used and the air quenching air velocity was 15 m / To prepare a lyocell fiber comprising multifilaments composed of monofilaments having a circular cross section with a cross-section diameter of 13.78 mu m.

Comparative Example 2

A lyocell fiber including a multifilament composed of monofilaments having a circular cross section with a diameter of 15.06 mu m was produced in the same manner as in Comparative Example 1, except that the monofilament had a fineness of 2.39 denier.

Comparative Example 3

Except that the ratio of the central long axis L1 of the monofilament and the straight line L2 at both ends of the central longitudinal axis was less than 1.0.

Comparative Example 4

Except that the ratio of the central long axis L1 of the monofilament to the straight line L2 at both ends of the central longitudinal axis was 2.8: 1, and the monofilament having the curved flat- A lyocell fiber containing multifilaments was prepared.

Comparative Example 5

Except that the length of the center long axis L1 of the monofilament was 11 mu m and the length of the center short axis S1 was 3 mu m.

Comparative Example 6

Filaments having a monofilament having a curvilinear flat section in the same manner as in Example 1 except that the length of the center long axis L1 of the monofilament was 43 mu m and the length of the center short axis S1 was 8 mu m Was prepared.

The cross-sectional shapes, cross-sectional areas, fineness and fiber thickness of the monofilaments contained in the lyocell fibers were measured and calculated for the lyocell fibers prepared in the Examples and Comparative Examples as follows, Respectively.

(1) Cross-sectional shape of the monofilament contained in the lyocell fiber

A small amount of fiber bundle was sampled and cut with a black cotton pad to make it thin. The cut was inserted into the hole of the plate, and cut with a razor blade so that the cross section was not pushed.

The images were enlarged (× 500) using an optical microscope (BX51, Olympus), and images were stored with a digital camera. The cross-sectional images of the fibers were analyzed using the Olympus soft imaging solution program and the lengths and areas of the major and minor axes, the fiber thicknesses, and the circumferential lengths were analyzed.

(2) Fineness

The monofilament cross-sectional area of the actual lyocell fibers obtained from the cross-sectional analysis and the density of the lyocell fibers (1.49 g / cm ³ ) were calculated to calculate the fineness of the lyocell fibers.

<Formula 1>

Fineness (De) = [density of the lyocell monofilament cross-sectional area of the fiber (㎛ ²⁾ × lyocell fiber ^{(g / cm 3) × 9000} (m)] / 1000000

Sectional shape of the monofilament
Fineness
(De) (占 퐉) / Fineness (De) L1 / S1 L1 / L2 Remarks Center long axis length
(L1, 占 퐉) Center short axis length
(S1, 占 퐉) Connection length of center long axis end
(L2, 占 퐉) Circumferential length
(탆) Actual cross-sectional area of the monofilament of the Lyocell fibers (탆 ² ) Example 1 23.8 5.9 19.8 61.0 148.9 2.0 30.5 4.0 1.2 Flat cross section Example 2 20.2 5.8 18.2 53.8 124.1 1.6 32.4 3.4 1.1 Flat cross section Example 3 29.0 6.20 21.0 69.7 178.4 2.4 29.2 4.7 1.4 Flat cross section Comparative Example 1 Circular cross section diameter: 13.7 43.2 149.0 2.0 21.6 - - Circular section Comparative Example 2 Circular cross section diameter: 15.0 47.3 178.0 2.4 19.8 - - Circular section Comparative Example 3 Not spinning Not measurable Comparative Example 4 34.5 4.22 12.2 77.8 146.4 1.95 39.9 8.1 2.8 Flat cross section Comparative Example 5 Not spinning Not measurable Comparative Example 6 43.1 8.8 18.2 104.4 380.4 5.0 20.6 4.8 2.3 Flat cross section

As shown in Table 1, the lyocell fibers of Examples 1 to 3 made of monofilaments having a flattened cross-section with a curvature were made from the lyocell fibers of Comparative Example 1 and Comparative Example 2 made of monofilaments having circular cross- The circumferential length was larger at the same fineness. This means that the specific surface area of the fiber is large, so that excellent physical properties as described above can be realized. Also, since the fiber thickness is small at the same fineness, this also can realize excellent physical properties. Further, the lyocell fibers of Examples 1 to 3 did not excessively increase in curvature compared to the lyocells of Comparative Examples 3 to 6, so that the interlaminar adhesiveness was excellent and the effect of the flat yarn was improved, The effect range can be shown.

Here, the cross-sectional shape of the lyocell fiber of Example 1 is as shown in Fig.

From these results, it can be seen that the lyocell fibers of Examples 1 to 3 have a large specific surface area and a small fiber thickness, and can be widely applied to fields requiring such characteristics.

<Experimental Example 2>

Examples and Comparative Lioness cell fibers steam box produced in Example (pressure conditions 0.2kgf / cm ²⁾ to pass through, while the pressure of the warm-up condition to give the temperature of the tow 2.0kgf / cm ² to stuffer box compress a ruler To make a crimp tow in a stuffer box, dry it through a lattice drier, and finally cut to produce a lyocell staple fiber having a 38 mm fiber length.

The fabricated lyocell staple fiber was finally manufactured through a carding and spun raising process, which is a process of producing a nonwoven fabric aggregate, and the weight of the nonwoven fabric aggregate was adjusted to the numerical values in Table 2 by adjusting the feed rate and the process speed And the deviation of the nonwoven fibrous aggregate to ± 10%.

The fabricated nonwoven fabric aggregates were measured for physical properties by the following measurement methods and are shown in Table 2 below.

<Measurement method>

(1) basis weight (gsm = g / m ² )

The nonwoven fibrous aggregate was sampled at a width of 5 cm and a length of 20 cm and weighed, and the basis weight was calculated by the following formula 2.

<Formula 2>

Basis weight = non-woven fiber aggregate sample weight measurement × 100

(2) Thickness

Mitutoyo no. 2046F. &Lt; / RTI &gt;

(3) Transparency

Sample preparation: Immerse the nonwoven fiber aggregate in water or essence for 10 minutes.

To measure the transparency of the nonwoven fiber aggregate, the haze meter (Nippon Denshoku Industry, NDH-5000), a light transmittance equipment, was used and the transmittance at a wavelength of nm was measured.

(4) Absorbency

After immersing the nonwoven fabric aggregate in water or essence, the weight of the nonwoven fabric aggregate was measured by measuring the before / after weight, and the ability of the nonwoven fabric aggregate to absorb water or essence was calculated by the following formula 3.

<Formula 3>

Absorbency (%) = {(Weight of nonwoven fabric aggregate after immersion - Weight of nonwoven fabric aggregate before immersion) / Weight of nonwoven fabric aggregate before immersion} × 100

(5) Skin adhesion

The nonwoven fiber aggregate is cut into a size of 25 mm x 150 mm, and immersed in water or essence for 10 minutes, and then adhered to the human arm. After adhering, the adhesive force (in gf) was measured using an Instron (Instron, Instron-3365), while leaving the nonwoven fibrous assembly out of the skin.

Basis weight
(gsm) thickness
(mm) Transparency
(%) Absorbency
(%) Skin adhesion (%) Example 1 50 0.42 Water 82
Essence 90 Water 1200
Essence 1400 Water 3.8
Essence 4.9 Example 2 40 0.39 Water 84
Essence 92 Water 1100
Essence 1250 Water 3.7
Essence 4.7 Example 3 60 0.46 Water 81
Essence 88 Water 1300
Essence 1500 Water 4.0
Essence 5.1 Comparative Example 1 40 0.45 Water 79
Essence 88 Water 950
Essence 1000 Water 3.3
Essence 4.3 Comparative Example 2 50 0.5 Water 78
Essence 86 Water 1000
Essence 1100 Water 3.5
Essence 4.5 Comparative Example 3 Not measurable - - - - Comparative Example 4 50 0.44 Water 80
Essence 88 Water 1200
Essence 1400 Water 3.6
Essence 4.6 Comparative Example 5 Not measurable - - - - Comparative Example 6 60 0.52 Water 74
Essence 82 Water 1400
Essence 1600 Water 3.8
Essence 4.8

As shown in Table 2, Examples 1 to 3 showed thinner thickness than the nonwoven fabric aggregates of Comparative Examples 1 and 2, and exhibited excellent transparency, absorbency, and adhesion due to the effect of the cross-section of flat fibers having curvature .

On the other hand, in Comparative Example 4, the curvature of the fiber was excessively high, so that the thickness of the nonwoven fabric aggregate was increased, and the properties other than the absorbency were similar to those of Comparative Examples 1 and 2. In Comparative Example 6, the thickness of the curvature fibers was increased, and the thickness of the nonwoven fabric aggregate was increased. As a result, the physical properties of the nonwoven fabric aggregate could not be improved as compared with Example 3,

While the present invention has been particularly shown and described with reference to specific embodiments thereof, those skilled in the art will appreciate that such specific embodiments are merely exemplary and that the scope of the invention is not limited thereby. something to do. Accordingly, the actual scope of the present invention will be defined by the appended claims and their equivalents.

L1: center long axis length, S1: center short axis length,
L2: Straight length of both ends of the center long axis

Claims (16)

The present invention relates to a nonwoven fabric assembly comprising a lyocell fiber,
The cross section of the monofilament constituting the lyocell fiber has a central longitudinal axis L1 and a central minor axis S1 and a length ratio between the central longitudinal axis L1 and the central minor axis S1 is 1.5: 1 to 10.5: 1 , And the ratio of the length of the center long axis (L1) to the length of the straight line (L2) at both ends of the center long axis is 1.0 to 1.5: 1. The nonwoven fabric assembly according to claim 1, wherein the length of the center long axis (L1) of the monofilament is 12 to 42 mu m, and the length of the center short axis (S1) is 4 to 7 mu m. The nonwoven fabric aggregate according to claim 1, wherein the monofilament has a fineness of 1.0 to 4.0 denier, and a value obtained by dividing a peripheral length of the monofilament by a fineness is 24.5 to 32 탆 / denier. The nonwoven fabric assembly according to claim 1, wherein the fineness of the lyocell fiber is 1.0 to 4.0 denier. The nonwoven fibrous assembly according to claim 1, wherein the fiber length of the lyocell fiber is 36 to 40 mm. The nonwoven fibrous assembly according to claim 1, wherein the lyocell fiber has a crimp number of 8 to 12 cpi. The nonwoven fabric assembly according to claim 1, wherein the lyocell fiber has an emulsion content of 0.1 to 0.4% by weight based on 100% by weight of the lyocell fiber. The nonwoven fabric assembly according to claim 1, wherein the basis weight of the nonwoven fabric aggregate is 30 to 60 g / m 2. The nonwoven fabric assembly according to claim 1, wherein the nonwoven fabric aggregate has a thickness of 0.3 to 0.5 mm. The nonwoven fabric assembly according to claim 1, wherein the nonwoven fabric aggregate has a water absorption rate of 1000 to 1600% based on the weight of the lyocell fiber. The nonwoven fabric assembly according to claim 1, wherein the nonwoven fabric aggregate has a transparency of 80 to 84% after the water treatment. The nonwoven fabric assembly according to claim 1, wherein the nonwoven fabric aggregate has a transparency of 88 to 94% after the essence treatment. The nonwoven fabric aggregate according to claim 1, wherein the nonwoven fabric aggregate has a skin adhesion of 3.6 to 4.2 gf after the water treatment. The nonwoven fabric assembly according to claim 1, wherein the nonwoven fabric aggregate has a skin adhesion of 4.5 to 5.3 gf after the essence treatment. The nonwoven fabric assembly according to claim 1, wherein the nonwoven fabric aggregate has an emulsion content of 0.001 wt% or less based on 100 wt% of the nonwoven fabric aggregate. A mask pack sheet using the nonwoven fabric assembly according to any one of claims 1 to 15.

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