Highly absorbent composite fiber, highly absorbent nonwoven fabric, and articles containing the same

Abstract

A highly absorbent composite fiber, a highly absorbent nonwoven fabric, and an article including the same are disclosed, and the highly absorbent composite fiber includes a core including a polyolefin resin and a sheath including EVOH (ethylene vinyl alcohol).

Description

[Technical field]

[0001] The present invention relates to a highly absorbent composite fiber, a highly absorbent nonwoven fabric, and an article containing the same, and more particularly to a highly absorbent composite fiber, a highly absorbent nonwoven fabric, and an article containing the same, which are excellent in absorbency and cooling sensation. [Background technology]

[0002] In general, nonwoven fabrics are required to have various properties depending on their applications.

[0003] For example, nonwoven fabrics used in sanitary products and beauty mask packs are required to have excellent water absorbency and a cooling sensation.

[0004] Therefore, various methods have been proposed to impart excellent water absorbency and cooling sensation to nonwoven fabrics, and a method of post-treating the nonwoven fabric with a hydrophilic emulsion after production is generally used. However, such a method has a drawback in that when the nonwoven fabric continuously absorbs water, the emulsion is washed away, causing the nonwoven fabric to lose its hydrophilicity and its absorbency to decrease.

[0005] For example, Korean Patent Publication No. 10-2106115 proposes a method of preparing a hydrophilic agent containing a nonionic surfactant, immersing a nonwoven fabric in the hydrophilic agent, and then drying the same. However, the above method has problems such as complicated steps, low productivity, and loss of hydrophilicity when the nonwoven fabric continuously absorbs water. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Korean Patent Registration No. 10-2106115 Summary of the Invention [Problem to be solved by the invention]

[0007] One embodiment of the present invention provides a highly absorbent composite fiber having excellent water absorption and cooling sensation.

[0008] Another embodiment of the present invention provides a highly absorbent nonwoven fabric comprising highly absorbent composite fibers.

[0009] Yet another embodiment of the present invention provides an article comprising the highly absorbent nonwoven fabric. [Means for solving the problem]

[0010] One aspect of the present invention is A core including a polyolefin resin; A composite fiber is provided, the composite fiber including a sheath including EVOH (ethylene vinyl alcohol) and PEG (polyethylene glycol).

[0011] The weight ratio of the core to the sheath is also 50-90:10-50.

[0012] The content of the PEG in the sheath is also 1 to 10 parts by weight per 100 parts by weight of the EVOH.

[0013] The sheath also has a melting index of 10 to 60 g / 10 min.

[0014] The sheath further contains 0.1 to 15 parts by weight of an inorganic additive per 100 parts by weight of the EVOH resin.

[0015] Another aspect of the present invention is A nonwoven fabric comprising the bicomponent fiber is provided.

[0016] The nonwoven fabric has a moisture absorption rate of 550 to 1,500% and a thermal conductivity of 0.1 W / m·K or more.

[0017] Yet another aspect of the present invention is An article is provided that includes the nonwoven fabric.

[0018] The article may also be a hygiene product or a beauty mask pack. Effect of the Invention

[0019] The highly absorbent composite fibers, highly absorbent nonwoven fabrics and articles according to the embodiments of the present invention may have excellent absorbency and cool sensation. [Brief description of the drawings]

[0020] [Figure 1] 1 is a cross-sectional view of a highly absorbent composite fiber according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Hereinafter, a highly absorbent composite fiber (hereinafter simply referred to as "composite fiber") according to an embodiment of the present invention will be described in detail.

[0022] A bicomponent fiber according to one embodiment of the present invention includes a core and a sheath.

[0023] The core also contains a polyolefin resin.

[0024] The polyolefin resin includes a homopolymer of propylene, a copolymer of propylene and various α-olefins, a homopolymer of ethylene, a copolymer of ethylene and various α-olefins, or a combination thereof.

[0025] The polyolefin resin is also hydrophobic.

[0026] The core also does not contain EVOH (ethylene vinyl alcohol) and PEG (polyethylene glycol).

[0027] In addition, since the core contains a hydrophobic olefin resin but does not contain EVOH, when the composite fiber and a nonwoven fabric containing the same are immersed in water, water is absorbed only on the surface of the composite fiber containing the EVOH, and water does not penetrate into the interior of the composite fiber, thereby preventing the volume of the core from expanding.

[0028] The sheath also comprises EVOH and PEG.

[0029] The EVOH is a copolymer of ethylene and vinyl alcohol, contains hydroxyl groups (OH) and has hydrophilicity, which allows it to absorb water well. The lower the ethylene content, the more hydroxyl groups there are, and the higher the water absorption rate can be.

[0030] The EVOH has a thermal conductivity of 0.3 to 0.4 W / m K, which is at least twice as high as the thermal conductivity of polypropylene (PP), an olefin resin, which is 0.1 to 0.15 W / m K. Thermal conduction refers to the transfer of heat from a high temperature area to a low temperature area within a substance, and when EVOH, which has high thermal conductivity, comes into contact with human skin, heat from the human body is transferred more easily to the EVOH, thereby producing a cooling sensation that gives a refreshing feeling.

[0031] The EVOH also has a melt index (MI (measurement temperature 210°C, load 2.16 kg)) of 10 to 60 g / 10 min, as measured according to ASTM D1238. If the melt index of the EVOH is less than 10 g / 10 min, the viscosity is very high, causing a rapid increase in nozzle pressure and making long-term production impossible, whereas if the melt index exceeds 60 g / 10 min, the viscosity is very low and it is difficult to form a composite fiber structure.

[0032] The EVOH also has a melting temperature (Tm) of 155°C to 185°C.

[0033] The PEG is a hydrophilic component, and when present in the sheath, it not only improves the moisture absorption rate of the nonwoven fabric containing the composite fiber, but also has a high latent heat value and can impart a sustained cooling effect.

[0034] The content of the PEG in the sheath is 1 to 10 parts by weight per 100 parts by weight of the EVOH. If the content of the PEG is less than 1 part by weight per 100 parts by weight of the EVOH, a higher water absorption rate than that of the EVOH alone cannot be realized, and if the content exceeds 10 parts by weight, the spinnability becomes poor and fiber breakage occurs.

[0035] The sheath further contains 0.1 to 15 parts by weight of an inorganic additive per 100 parts by weight of the EVOH resin. If the content of the inorganic additive is less than 0.1 part by weight per 100 parts by weight of the EVOH resin, the effect of adding the additive is insignificant, whereas if the content of the inorganic additive is more than 15 parts by weight, the additive is not uniformly distributed due to its low dispersibility, which may cause thread breakage.

[0036] The inorganic additive serves to further improve the cooling effect of the nonwoven fabric including the composite fiber.

[0037] The inorganic additive also has a thermal conductivity of 0.5 W / m·K or more. If the thermal conductivity of the inorganic additive is less than 0.5 W / m·K, a sufficient cooling effect cannot be imparted.

[0038] The inorganic additive may also include titanium dioxide (TiO2), calcium carbonate (CaCO3), zinc oxide (ZnO), aluminum oxide (Al2O3), graphene, or a combination thereof.

[0039] The weight ratio of the core to the sheath is also 50-90:10-50. If the weight ratio of the sheath is less than 10, high moisture absorption rate and cooling effect cannot be obtained, and if the weight ratio of the sheath is more than 50, fiber spinning is impossible.

[0040] Another aspect of the present invention provides a highly absorbent nonwoven fabric (hereinafter simply referred to as "nonwoven fabric") comprising the above-mentioned composite fiber.

[0041] The nonwoven fabric has a water absorption rate (W f ) is 550 to 1,500%.

[0042]

number

[0043] The nonwoven fabric also has a thermal conductivity of 0.1 W / m·K or more.

[0044] Yet another aspect of the present invention provides an article comprising the nonwoven fabric.

[0045] The article may also be a hygiene product or a beauty mask pack.

[0046] The present invention will be described in more detail below with reference to examples. These examples are provided to more specifically explain the present invention, and the scope of the present invention is not limited to these examples.

[0047] Comparative Example 1: Production of composite fibers and nonwoven fabrics Polypropylene was used for the core, and EVOH with a melting point of 171°C and a melt index of 50g / 10min (measurement temperature 210°C, load 2.16kg) was used for the sheath. The temperature of the extruder melting the resin was 220°C. The melted resin was transferred to the core by a distributor in the composite spinning nozzle, and the EVOH was transferred to the sheath, and the composite fibers were spun through the nozzle at a speed of 2,500mpm in a composite cross-sectional form. The composite fibers were then defibrated to form a web, which was then calendered to produce a nonwoven fabric. The core:sheath ratio of the filaments formed above was 70:30 by weight.

[0048] Example 1: Production of composite fibers and nonwoven fabrics A composite fiber and a nonwoven fabric were produced in the same manner as in Comparative Example 1, except that 5 parts by weight of PEG per 100 parts by weight of EVOH resin was added to the sheath.

[0049] Example 2: Production of composite fibers and nonwoven fabrics Composite fibers and nonwoven fabrics were produced in the same manner as in Comparative Example 1, except that 5 parts by weight of PEG per 100 parts by weight of EVOH resin was added to the sheath, and the weight ratio of core:sheath was changed to 50:50.

[0050] Example 3: Preparation of composite fibers and nonwoven fabrics Composite fibers and nonwoven fabrics were produced in the same manner as in Comparative Example 1, except that 5 parts by weight of PEG per 100 parts by weight of EVOH resin was added to the sheath, and the weight ratio of core:sheath was changed to 90:10.

[0051] Example 4: Preparation of composite fibers and nonwoven fabrics A composite fiber and a nonwoven fabric were produced in the same manner as in Comparative Example 1, except that 1 part by weight of PEG was added to the sheath per 100 parts by weight of EVOH resin.

[0052] Example 5: Production of composite fibers and nonwoven fabrics A composite fiber and a nonwoven fabric were produced in the same manner as in Comparative Example 1, except that 10 parts by weight of PEG per 100 parts by weight of EVOH resin was added to the sheath.

[0053] Comparative Example 2: Production of composite fibers and nonwoven fabrics Composite fibers and nonwoven fabrics were produced in the same manner as in Comparative Example 1, except that 7 parts by weight of calcium carbonate (CaCO3) was added to the sheath as an inorganic additive having a thermal conductivity of 2.5 W / m K per 100 parts by weight of EVOH resin.

[0054] Comparative Example 3: Production of composite fiber and nonwoven fabric Composite fibers and nonwoven fabrics were produced in the same manner as in Comparative Example 1, except that 7 parts by weight of calcium carbonate (CaCO3) was added to the sheath as an inorganic additive with a thermal conductivity of 2.5 W / m K per 100 parts by weight of EVOH resin, and the weight ratio of the core:sheath was changed to 50:50.

[0055] Comparative Example 4: Production of composite fiber and nonwoven fabric Composite fibers and nonwoven fabrics were produced in the same manner as in Comparative Example 1, except that 15 parts by weight of calcium carbonate (CaCO3) was added to the sheath as an inorganic additive having a thermal conductivity of 2.5 W / m K per 100 parts by weight of EVOH resin.

[0056] Example 6: Production of composite fibers and nonwoven fabrics Composite fibers and nonwoven fabrics were produced in the same manner as in Comparative Example 1, except that 5 parts by weight of PEG and 7 parts by weight of calcium carbonate (CaCO3) as an inorganic additive with a thermal conductivity of 2.5 W / m K per 100 parts by weight of EVOH resin were added to the sheath.

[0057] Example 7: Preparation of composite fibers and nonwoven fabrics Composite fibers and nonwoven fabrics were produced in the same manner as in Comparative Example 1, except that 5 parts by weight of PEG and 7 parts by weight of calcium carbonate (CaCO3) as an inorganic additive with a thermal conductivity of 2.5 W / m K per 100 parts by weight of EVOH resin were added to the sheath, and the core:sheath weight ratio was changed to 50:50.

[0058] Comparative Example 5: Production of composite fiber and nonwoven fabric Composite fibers and nonwoven fabrics were produced in the same manner as in Comparative Example 1, except that 5 parts by weight of PEG per 100 parts by weight of EVOH resin was added to the sheath, and the weight ratio of core:sheath was changed to 45:55.

[0059] Comparative Example 6: Production of composite fiber and nonwoven fabric Composite fibers and nonwoven fabrics were produced in the same manner as in Comparative Example 1, except that 5 parts by weight of PEG per 100 parts by weight of EVOH resin was added to the sheath, and the weight ratio of core:sheath was changed to 95:5.

[0060] Comparative Example 7: Production of composite fiber and nonwoven fabric A composite fiber and a nonwoven fabric were produced in the same manner as in Comparative Example 1, except that 0.5 parts by weight of PEG per 100 parts by weight of EVOH resin was added to the sheath.

[0061] Comparative Example 8: Production of composite fiber and nonwoven fabric A composite fiber and a nonwoven fabric were produced in the same manner as in Comparative Example 1, except that 12 parts by weight of PEG per 100 parts by weight of EVOH resin was added to the sheath.

[0062] Comparative Example 9: Production of composite fiber and nonwoven fabric Composite fibers and nonwoven fabrics were produced in the same manner as in Comparative Example 1, except that 7 parts by weight of calcium carbonate (CaCO3) was added to the sheath as an inorganic additive with a thermal conductivity of 2.5 W / m K per 100 parts by weight of EVOH resin, and the core:sheath weight ratio was changed to 45:55.

[0063] Comparative Example 10: Production of composite fiber and nonwoven fabric Composite fibers and nonwoven fabrics were produced in the same manner as in Comparative Example 1, except that 7 parts by weight of calcium carbonate (CaCO3) was added to the sheath as an inorganic additive with a thermal conductivity of 2.5 W / m K per 100 parts by weight of EVOH resin, and the core:sheath weight ratio was changed to 95:5.

[0064] Comparative Example 11: Production of composite fiber and nonwoven fabric Composite fibers and nonwoven fabrics were produced in the same manner as in Comparative Example 1, except that 17 parts by weight of calcium carbonate (CaCO3) was added to the sheath as an inorganic additive with a thermal conductivity of 2.5 W / m K per 100 parts by weight of EVOH resin.

[0065] Comparative Example 12: Production of composite fiber and nonwoven fabric Composite fibers and nonwoven fabrics were produced in the same manner as in Comparative Example 1, except that 0.5 parts by weight of PEG and 0.05 parts by weight of calcium carbonate (CaCO3) as an inorganic additive with a thermal conductivity of 2.5 W / m K per 100 parts by weight of EVOH resin were added to the sheath.

[0066] Comparative Example 13: Production of composite fiber and nonwoven fabric Composite fibers and nonwoven fabrics were produced in the same manner as in Comparative Example 1, except that 12 parts by weight of PEG and 17 parts by weight of calcium carbonate (CaCO3) as an inorganic additive with a thermal conductivity of 2.5 W / m K per 100 parts by weight of EVOH resin were added to the sheath.

[0067] Comparative Example 14: Production of composite fiber and nonwoven fabric A composite fiber and a nonwoven fabric were produced in the same manner as in Comparative Example 1, except that the weight ratio of the core:sheath was changed to 100:0.

[0068] Evaluation example The moisture absorption rate was evaluated according to the above formula 1, and the thermal conductivity was also evaluated. The results are shown in Table 1 below.

[0069] [Table 1] Referring to Table 1, the nonwoven fabrics produced in Examples 1 to 7 are excellent in both moisture absorption rate (≧550%) and thermal conductivity (≧0.1 W / m·K).

[0070] On the other hand, the nonwoven fabrics produced in Comparative Examples 1 to 4, 6, 7, 10, 12 and 14 are shown to have excellent thermal conductivity (≧0.1 W / m·K) but low moisture absorption rate (<550%).

[0071] In addition, in Comparative Examples 5, 8, 9, 11 and 13, spinning was impossible, so that it was not possible to produce nonwoven fabrics and it was not possible to measure the thermal conductivity and the moisture absorption rate.

[0072] Although the present invention has been described with reference to the drawings and embodiments, they are merely illustrative, and a person skilled in the art will understand that various modifications and equivalent embodiments are possible therefrom. Therefore, the true technical scope of the present invention is defined by the technical ideas of the claims.

Claims

1. A nonwoven fabric comprising composite fibers, the composite fibers comprising: A core made of a polyolefin resin; a sheath including EVOH (ethylene vinyl alcohol) and PEG (polyethylene glycol); The weight ratio of the core to the sheath is 50-90:10-50; The core is free of EVOH and PEG; The content of PEG in the sheath is 1 to 10 parts by weight based on 100 parts by weight of EVOH, The EVOH is a nonwoven fabric having a melt index (MI (measurement temperature: 210°C, load: 2.16 kg)) of 10 to 60 g / 10 min, as measured by ASTM D1238, and a melt temperature (Tm) of 155°C to 185°C.

2. The nonwoven fabric according to claim 1, wherein the melt index of the sheath is 10 to 60 g / 10 min.

3. 2. The nonwoven fabric according to claim 1, wherein the nonwoven fabric has a moisture absorption rate of 550 to 1,500% and a thermal conductivity of 0.1 W / m·K or more.

4. An article comprising the nonwoven fabric of claim 1.

5. The article according to claim 4 , which is a hygiene product or a beauty mask pack.

Images