Lyocell nonwoven fabric comprising fibers of different fineness

Abstract

The present invention relates to a lyocell nonwoven fabric suitable for use in a mask pack, the lyocell nonwoven fabric being manufactured in a single step and having fibers of various degrees of fineness. The present invention includes: a first fiber having a fineness of less than 1 µm; a second fiber having a fineness of 1 µm to 5 µm (exclusive of 5 µm); a third fiber having a fineness of 5 µm to 10 µm (exclusive of 10 µm); a fourth fiber having a fineness of 10 µm to 15 µm (exclusive 15 µm); and a fifth fiber having a fineness of 15 µm or more.

Description

Lyocell nonwoven fabric containing fibers of different fineness

[0001] Cross-reference to related applications

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2023-0197337, filed December 19, 2023, the contents of which are incorporated herein by reference in their entirety.

[0003] The present invention relates to a lyocell nonwoven fabric comprising fibers having different finenesses.

[0004] Among the conventional nonwoven fabrics for mask packs, the Spunlace method of carding short fibers produces nonwoven fabrics through a two-step process of short fiber manufacturing and Spunlace, so the absorbency and transparency are reduced, and a separate post-processing is required to produce nonwoven fabrics of a quality suitable for mask packs, which has the disadvantage of a long process and high post-processing costs.

[0005] Meanwhile, non-woven fabrics for mask packs manufactured through 1step have issues with toxicity because they use cuprammonium solvent, have limitations in raw material supply because they use cotton linter pulp, and have cost issues due to exclusive production / sales.

[0006] In addition, long-fiber nonwoven fabrics with the same fineness of 15㎛ have large pores, so they have a high absorption rate but a problem of low adhesion.

[0007] The problem to be solved by the present invention is to provide a lyocell nonwoven fabric suitable for use in mask packs by being manufactured in one step and having various finenesses.

[0008] The present invention is a Lyocell nonwoven fabric comprising: a first fiber having a fineness of less than 1 ㎛; a second fiber having a fineness of 1 ㎛ or more and less than 5 ㎛; a third fiber having a fineness of 5 ㎛ or more and less than 10 ㎛; a fourth fiber having a fineness of 10 ㎛ or more and less than 15 ㎛; and a fifth fiber having a fineness of 15 ㎛ or more.

[0009] In the present invention, the first fiber may be 10 to 30 wt% relative to the total weight of the nonwoven fabric, the second fiber may be 20 to 40 wt% relative to the total weight of the nonwoven fabric, the third fiber may be 20 to 40 wt% relative to the total weight of the nonwoven fabric, the fourth fiber may be 10 to 20 wt% relative to the total weight of the nonwoven fabric, and the fifth fiber may be 10 to 20 wt% relative to the total weight of the nonwoven fabric.

[0010] In the present invention, the first fiber, second fiber, third fiber, fourth fiber, and fifth fiber may be manufactured from a solution containing wood pulp, an aqueous solution of NMMO (N-methyl morpholine N-oxide), and an antioxidant.

[0011] In the present invention, the first fiber, second fiber, third fiber, fourth fiber, and fifth fiber may be manufactured from a solution containing 5 to 15 wt% of wood pulp, 80 to 90 wt% of NMMO (N-methyl morpholine N-oxide) aqueous solution, and 0.01 to 5 wt% of antioxidant.

[0012] In the present invention, the first fiber, the second fiber, the third fiber, the fourth fiber, and the fifth fiber may be made of cellulose.

[0013] In the present invention, the nonwoven fabric may be for a mask pack.

[0014] The lyocell nonwoven fabric according to the present invention is manufactured in one step and contains various fibers, thereby reducing the manufacturing cost.

[0015] Additionally, it is environmentally friendly by using cellulose raw materials.

[0016] Additionally, by using fibers with various finenesses, it is possible to improve adhesion while achieving high absorption rate.

[0017] Hereinafter, the present invention will be described in more detail with reference to exemplary embodiments, examples, etc. so that those skilled in the art can easily implement the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments, examples, etc. described herein.

[0018] Additionally, when the terms “about,” “approximately,” or similar expressions such as “at least” are used in connection with a numerical value in the present invention, it is intended that a theoretical, experimental, statistical, or empirical error of ±10%, ±7%, ±5%, ±3%, ±2%, or ±1% based on that numerical value is allowed.

[0019]

[0020] In the present invention, lyocell is a natural fiber made by extracting fibers from trees, and can be manufactured using cellulose in the present invention.

[0021] The present invention is a Lyocell nonwoven fabric comprising: a first fiber having a fineness of less than 1 ㎛; a second fiber having a fineness of 1 ㎛ or more and less than 5 ㎛; a third fiber having a fineness of 5 ㎛ or more and less than 10 ㎛; a fourth fiber having a fineness of 10 ㎛ or more and less than 15 ㎛; and a fifth fiber having a fineness of 15 ㎛ or more.

[0022] In the present invention, the first fiber is a fiber having a fineness of less than 1 ㎛, preferably, the fineness of the first fiber may be 0.01 ㎛ or more and less than 1 ㎛, and the average fineness of the first fiber included in the lyocell nonwoven fabric may be 0.2 to 0.8 ㎛.

[0023] Additionally, the content of the first fiber may be 10 to 30 wt% based on the total weight of the nonwoven fabric, and preferably 13 to 25 wt%.

[0024] When the fineness and content of the first fiber are within the above range, the lyocell nonwoven fabric can have various finenesses, thereby improving the absorbency and adhesion.

[0025] In the present invention, the second fiber is a fiber having a fineness of 1 µm or more and less than 5 µm, preferably, the fineness of the second fiber may be 2 µm to 4.5 µm, and the average fineness of the second fiber included in the lyocell nonwoven fabric may be 2.2 to 3.9 µm.

[0026] Additionally, the content of the second fiber may be 20 to 40 wt% based on the total weight of the nonwoven fabric, and preferably 22 to 35 wt%.

[0027] When the fineness and content of the second fiber are within the above range, the lyocell nonwoven fabric can have various finenesses, thereby improving the absorbency and adhesion.

[0028] In the present invention, the third fiber is a fiber having a fineness of 5 ㎛ or more and less than 10 ㎛, preferably, the fineness of the third fiber may be 5.1 ㎛ to 9 ㎛, and the average fineness of the third fiber included in the lyocell nonwoven fabric may be 5.3 to 8.4 ㎛.

[0029] Additionally, the content of the third fiber may be 20 to 40 wt% based on the total weight of the nonwoven fabric, and preferably 21 to 35 wt%.

[0030] When the fineness and content of the third fiber are within the above range, the lyocell nonwoven fabric can have various finenesses, thereby improving the absorbency and adhesion.

[0031] In the present invention, the fourth fiber is a fiber having a fineness of 10 ㎛ or more and less than 15 ㎛, preferably, the fineness of the fourth fiber may be 11 ㎛ to 14 ㎛, and the average fineness of the fourth fiber included in the lyocell nonwoven fabric may be 11.5 to 13.5 ㎛.

[0032] Additionally, the content of the fourth fiber may be 10 to 20 wt% based on the total weight of the nonwoven fabric, and preferably 10 to 19 wt%.

[0033] When the fineness and content of the fourth fiber are within the above range, the lyocell nonwoven fabric can have various finenesses, thereby improving the absorbency and adhesion.

[0034] In the present invention, the fifth fiber is a fiber having a fineness of 15 µm or more, preferably, the fineness of the fifth fiber may be 15 µm to 25 µm, and the average fineness of the fifth fiber included in the lyocell nonwoven fabric may be 15.3 to 21.2 µm.

[0035] Additionally, the content of the fifth fiber may be 10 to 20 wt% based on the total weight of the nonwoven fabric, and preferably 10 to 19 wt%.

[0036] When the fineness and content of the fifth fiber are within the above range, the lyocell nonwoven fabric can have various finenesses, thereby improving the absorbency and adhesion.

[0037] In the present invention, the first fiber, second fiber, third fiber, fourth fiber, and fifth fiber may be manufactured from a solution containing wood pulp, an N-methyl morpholine N-oxide (NMMO) aqueous solution, and an antioxidant, and preferably, may be manufactured from a solution containing 5 to 15 wt% of wood pulp, 80 to 90 wt% of an N-methyl morpholine N-oxide (NMMO) aqueous solution, and 0.01 to 5 wt% of an antioxidant.

[0038] In the present invention, if the content of wood pulp is less than 5 wt%, the productivity of the lyocell nonwoven fabric may decrease, and if it exceeds 15 wt%, the viscosity of the solution may increase, resulting in decreased spinnability.

[0039] In the present invention, if the content of the NMMO (N-methyl morpholine N-oxide) aqueous solution is less than 80 wt%, productivity may decrease, and if it exceeds 90%, viscosity may increase and spinnability may decrease.

[0040] In addition, in the present invention, the concentration of the NMMO (N-methyl morpholine N-oxide) aqueous solution may be 40 to 95%, and productivity and radioactivity may be improved within the above range.

[0041] In the present invention, the antioxidant may be Propyl gallate.

[0042] In the present invention, the first fiber, the second fiber, the third fiber, the fourth fiber, and the fifth fiber may be made of lyocell.

[0043] The lyocell nonwoven fabric according to the present invention may have an absorption rate of 500% or more, a drying time of 25 minutes or more, an adhesion rate of 7 minutes or more, and a transparency of 70% or more, as measured by the following measurement method, and preferably, an absorption rate of 510% or more, a drying time of 30 minutes or more, an adhesion rate of 8 minutes or more, and a transparency of 75% or more, and thus, at least one of the absorption rate, drying time, adhesion rate, and transparency properties is very superior to that of a fabric manufactured using each type of fiber. In addition, by exhibiting such properties, the lyocell nonwoven fabric may be used as a wiper, cosmetic cotton, mask pack, etc. used in a semiconductor clean room, and preferably, may be used as a mask pack.

[0044]

[0045] The lyocell nonwoven fabric according to the present invention can be manufactured by the following method.

[0046] After dissolving the antioxidant in water, it is mixed with the NMMO aqueous solution and concentrated. The concentrate is then fed into an extruder, cellulose pulp is added, and dope is produced. The dope is then fed into a spinneret and discharged. Hot air is blown at an angle of 10 to 80 degrees to the discharge direction to adjust the fineness, and the NMMO and antioxidant are removed, after which a nonwoven fabric is produced.

[0047] Hereinafter, specific examples according to the present invention will be described.

[0048]

[0049] Examples and Comparative Examples

[0050] After dissolving the antioxidant (propyl gallate) in water at 80℃, mix it with an aqueous NMMO solution with a concentration of 50%. Then, the concentration is concentrated to 87% through a concentrator. The concentrate is put into a twin screw extruder at 100℃, and wood pulp is fed into the side feeder of the extruder to produce a dope with a melt viscosity of 7,000 to 13,000 P (poise). After that, the dope is put into the spinneret and discharged at a voltage of 50Kv at approximately 200 cc / min. When discharged, hot air is blown at an angle of 10 to 80° to the discharge direction to adjust the fineness and form a web, and while moving the belt at 1 to 10 m / min, water at 30 to 80℃ is treated with a high-pressure spray to wash and solidify the NMMO and antioxidant. The solidified lyocell nonwoven fabric is dried in a dryer and then wound with a winder to manufacture it. The average fineness of each fiber included in the manufactured lyocell nonwoven fabric is as shown in Table 1 below, and the weight % of each fiber constituting the nonwoven fabric is as shown in Table 2 below.

[0051]

[0052] Classification 1st fiber (㎛) 2nd fiber (㎛) 3rd fiber (㎛) 4th fiber (㎛) 5th fiber (㎛) Example 10.7 3.8 6.1 12.4 21.2 Example 20.5 2.9 8.4 13.1 18.3 Example 30.6 3.3 5.8 11.6 17.6 Example 40.3 2.3 5.3 12.7 15.3 Comparative Example 10.7 ----Comparative Example 2-2.4---Comparative Example 3--8.7--Comparative Example 4---9.8-Comparative Example 5----15.3

[0053] Classification 1st fiber (weight%) 2nd fiber (weight%) 3rd fiber (weight%) 4th fiber (weight%) 5th fiber (weight%) Example 1 1 3 2 3 2 9 1 8 1 7 Example 2 1 6 3 1 2 7 1 3 1 3 Example 3 2 1 3 3 2 2 1 3 1 1 Example 4 2 4 3 3 2 2 1 1 0 Comparative Example 1 1 0 0 ---- Comparative Example 2 - 100 - --- Comparative Example 3 - 100 - --- Comparative Example 4 - 100 - Comparative Example 5 - 100

[0054] Experimental example

[0055] The absorption rate, drying time, adhesion, and transparency of the lyocell nonwoven fabric manufactured in the above examples and comparative examples were measured using the following methods, and the results are shown in Table 3 below.

[0056] [measurement method]

[0057] - Absorption rate: KS K 9072 evaluation method, 90mm x 60mm diameter circular test piece is immersed in distilled water for more than 1 second, and the absorption amount is measured by measuring the weight before and after absorption.

[0058] - Drying time: KS K 9071 evaluation method, drying time is measured using an infrared moisture meter on a 90mm diameter circular test piece until the moisture content becomes less than or equal to

[0059] - Adhesion: The standard is a method commonly used in the industry to measure the time it takes for a sample (4cm X 6cm) to be absorbed into water and attached to an acrylic plate.

[0060] - Transparency: ASTM D1003 evaluation method, pour in distilled water 10 times the mass of the specimen, take it out, and measure transparency after 1 second.

[0061]

[0062] Classification Absorption rate (%) Drying time (min) Adhesion (min) Transparency (%) Example 1 5 5 3 3 9 7 5 Example 2 5 6 8 3 1 1 0 7 9 Example 3 5 3 2 3 6 1 2 8 3 Example 4 5 1 4 3 2 1 3 8 1 Comparative example 1 3 3 3.4 3.6 1 3 Comparative example 2 6 2 2.2 4.5 1 6 Comparative example 3 4 7 0 3.5 1 3 6 7 Comparative example 4 5 2 0 4.5 1 3 5 0 Comparative example 5 5 0 2.0 5.8 0

[0063] Referring to Table 3 above, in the case of nonwoven fabrics manufactured using five types of fibers with different finenesses according to the present invention (Examples 1 to 5), the absorption rate is 500% or more, the drying time is 30 minutes or more, the adhesion rate is 9 minutes or more, and the transparency is 75% or more, whereas in the case manufactured using each type of fiber, Comparative Example 1 with a general electrospun fineness and Comparative Example 2 with a melt-brown fineness have very low absorption rate, drying time, adhesion rate, and transparency. In addition, it can be confirmed that Comparative Example 3 with a fineness suitable for general mask packs has low absorption rate and transparency, and Comparative Example 4 has very low transparency.

[0064] In addition, it can be confirmed that Comparative Example 5, which is of a fineness suitable for high-end mask packs, has very low adhesion.

[0065] It can be confirmed that the lyocell nonwoven fabric according to the present invention has at least one of the following properties superior to that of a conventional nonwoven fabric manufactured using a single type of fiber: absorption rate, drying time, adhesion, and transparency; and since it is manufactured in one step, the process can be simplified, and since it is manufactured from wood pulp, it is environmentally friendly.

Claims

1. First fiber having a fineness of less than 1 ㎛; Second fiber having a fineness of 1 ㎛ or more and less than 5 ㎛; Third fiber having a fineness of 5 ㎛ or more and less than 10 ㎛; A fourth fiber having a fineness of 10 ㎛ or more and less than 15 ㎛; and Lyocell nonwoven fabric comprising fifth fibers having a fineness of 15㎛ or more.

2. In paragraph 1, The above first fiber is 10 to 30 wt% relative to the total weight of the nonwoven fabric. The above second fiber is 20 to 40 wt% based on the total weight of the nonwoven fabric. The above third fiber is 20 to 40 wt% of the total weight of the nonwoven fabric, The above fourth fiber is 10 to 20 wt% based on the total weight of the nonwoven fabric. The above fifth fiber is 10 to 20 wt% based on the total weight of the nonwoven fabric. It is a lyocell nonwoven fabric.

3. In paragraph 1, A lyocell nonwoven fabric, wherein the first fiber, the second fiber, the third fiber, the fourth fiber, and the fifth fiber are manufactured from a solution containing wood pulp, an aqueous solution of NMMO (N-methyl morpholine N-oxide), and an antioxidant.

4. In paragraph 1, The above first fiber, second fiber, third fiber, fourth fiber and fifth fiber, A lyocell nonwoven fabric manufactured from a solution containing 5 to 15 wt% of wood pulp, 80 to 90 wt% of an NMMO (N-methyl morpholine N-oxide) aqueous solution, and 0.01 to 5 wt% of an antioxidant.

5. In paragraph 1, The above first fiber, second fiber, third fiber, fourth fiber and fifth fiber, Lyocell nonwoven fabric made of lyocell.

6. In paragraph 1, The above nonwoven fabric is a lyocell nonwoven fabric for use as a mask pack.