Nonwoven fabrics, nonwoven fabric laminates and articles

Abstract

Nonwoven fabrics, nonwoven laminates and articles are provided. The nonwoven fabric of the present invention has a unit weight (g / m 2 ) specific surface area of ​​fiber (m 2 / m 2 ) is 0.20~0.28m 2 / g, the amount of hydrophilic agent impregnated on the nonwoven fabric (EPU: emulsion pick-up) is 13 to 23 wt%, and the content of the hydrophilic agent fixed on the nonwoven fabric after drying (AOL: add-on level) is 0.3 to 0.6 wt% or less.

Description

[Technical Field]

[0001] The present invention relates to a nonwoven fabric, a nonwoven fabric laminate, and an article, and more particularly to a nonwoven fabric, a nonwoven fabric laminate, and an article that can reduce the amount of backflow and reduce discomfort and skin troubles caused by the wet environment of the nonwoven fabric. [Background technology]

[0002] Nonwoven fabrics have been used in a variety of fields, such as hygiene, medical, agricultural, and industrial fields, by modifying their physicochemical properties. In particular, with the recent improvement in living standards, nonwoven fabrics have been widely used in everyday life as sanitary products, such as absorbent articles, e.g., diapers and sanitary napkins.

[0003] In most cases, such nonwoven fabrics for sanitary materials require a hydrophilization treatment process depending on their intended use, and this hydrophilization treatment process is one of the most basic post-processing techniques applied in the production of long-fiber spunbonded nonwoven fabrics.

[0004] The hydrophilized nonwoven fabric can be used as a lining for disposable sanitary materials that come into direct contact with the bodies of infants and adults, as well as for agricultural materials such as mulching and seedling beds, roofing, house wrap, etc.

[0005] As described above, various methods for treating a nonwoven fabric with a hydrophilic agent have been disclosed in Korean Patent No. 10-0746819, Korean Patent Publication No. 10-2006-0116897, and Korean Patent Publication No. 10-2015-0057061.

[0006] However, nonwoven fabrics that have been hydrophilically treated by the methods disclosed in the above patents still have the problem of causing discomfort and skin troubles to the wearer when exposed to a humid environment. Summary of the Invention [Problem to be solved by the invention]

[0007] The problem to be solved by the present invention is to provide a nonwoven fabric that reduces the amount of backflow and reduces discomfort and skin troubles to the wearer caused by the wet environment of the nonwoven fabric.

[0008] Another problem to be solved by the present invention is to provide a nonwoven fabric laminate containing two or more sheets of the nonwoven fabric.

[0009] A further problem to be solved by the present invention is to provide an article comprising the nonwoven fabric laminate. [Means for solving the problem]

[0010] One aspect of the present invention is to provide a method for determining the unit weight (g / m) of a nonwoven fabric. 2 ) specific surface area of ​​fiber (m 2 / m 2 ) is 0.20~0.28m 2 / g, The present invention provides a nonwoven fabric in which the emulsion pick-up (EPU) of the hydrophilic agent applied to the nonwoven fabric is 13 to 23 wt%, and the content of the hydrophilic agent that adheres to the nonwoven fabric after drying (AOL: add-on level) is 0.3 to 0.6 wt% or less.

[0011] The nonwoven fabric has a unit weight (g / m 2 The amount of reflux per (g) is 0.105 to 0.177g / (g / m 2 )

[0012] The nonwoven fabric has a moisture content of 0.5 wt % or less.

[0013] The nonwoven fabric has a static friction coefficient of 0.350 to 0.430 and a dynamic friction coefficient of 0.300 to 0.430.

[0014] Another aspect of the present invention provides a nonwoven fabric laminate having a layer structure of at least two layers, at least one of which is the above-mentioned nonwoven fabric.

[0015] The nonwoven fabric may be a spunbond nonwoven fabric, and the nonwoven fabric laminate may be configured such that the spunbond nonwoven fabric is exposed on only one of the two surface layers.

[0016] Yet another aspect of the present invention provides an article comprising the nonwoven laminate.

[0017] The article may be a diaper, an absorbent article, a disposable hygiene product, a toileting product, a side gather, a support layer or a top sheet. [Effects of the Invention]

[0018] The nonwoven fabric according to one embodiment of the present invention can reduce the amount of backflow, thereby reducing discomfort and skin troubles caused by the wet environment of the nonwoven fabric. DETAILED DESCRIPTION OF THE INVENTION

[0019] Hereinafter, a nonwoven fabric according to one embodiment of the present invention will be described in detail.

[0020] The nonwoven fabric according to one embodiment of the present invention has a unit weight (g / m 2 ) specific surface area of ​​fiber (m 2 / m 2 ) is 0.20~0.28m 2 / g, the emulsion pick-up (EPU) of the hydrophilic agent applied to the nonwoven fabric is 13 to 23 wt%, and the content of the hydrophilic agent fixed to the nonwoven fabric after drying (AOL: add-on level) is 0.3 to 0.6 wt% or less.

[0021] The unit weight of the nonwoven fabric (g / m 2 ) specific surface area of ​​fiber (m 2 / m 2By adjusting the water content (W), emulsion pick-up rate (EPU) of the hydrophilic agent, and amount of hydrophilic agent after drying (AOL) within the above ranges, a nonwoven fabric having a low moisture content and a low backflow amount per unit weight of nonwoven fabric, and an appropriate level of static and dynamic friction coefficients can be obtained.

[0022] The emulsion pick-up (EPU) of the hydrophilic agent is calculated by the following formula 1. [Formula 1] EPU(%)=(W1-W0) / W0×100 In the above formula 1, W0 is the unit weight (g / m) of the nonwoven fabric before impregnation with the hydrophilic agent. 2 ) and W1 is the unit weight (g / m 2 ) and the emulsion means an emulsion formed by dispersing a hydrophilic agent in water at a concentration of 15 wt%.

[0023] The content of hydrophilic agent after drying (AOL) is calculated by the following formula 2. [Formula 2] AOL(%)=(W2-W0) / W0×100 In the above formula 2, W0 is the unit weight (g / m) of the nonwoven fabric before impregnation with the hydrophilic agent. 2 ) and W2 is the unit weight (g / m) of the nonwoven fabric after impregnation with the emulsion of the hydrophilic agent and drying. 2 )

[0024] In addition, the nonwoven fabric has a unit weight (g / m 2 The amount of reflux per (g) is 0.105 to 0.177g / (g / m 2 )

[0025] The nonwoven fabric has a moisture content of 0.5 wt % or less. If the moisture content of the nonwoven fabric is within this range, the growth of mold on the nonwoven fabric can be suppressed.

[0026] The nonwoven fabric has a static friction coefficient of 0.350 to 0.430 and a dynamic friction coefficient of 0.300 to 0.430.

[0027] The nonwoven fabric may contain crimped bicomponent fibers (hereinafter simply referred to as "bicomponent fibers").

[0028] The bicomponent fiber may include a first propylene polymer and a second propylene polymer.

[0029] The melting point of the second propylene polymer measured by differential scanning calorimetry (DSC) is higher than the melting point of the first propylene polymer by 30° C. or more.

[0030] The ratio of the melt flow rates (MFR: measurement temperature 230°C, load 2.16 kg) of the first propylene polymer to the second propylene polymer measured according to ASTM D1238 (the second propylene polymer / the first propylene polymer) is 1.5 or more.

[0031] For example, the melting point of the first propylene polymer is higher by 30° C. to 60° C. or 30° C. to 100° C. than the melting point of the second propylene polymer.

[0032] For example, the melt index ratio (the second propylene polymer / the first propylene polymer) is 1.7 to 2.0, 1.7 to 3.0, or 1.7 to 4.0.

[0033] The first propylene polymer and the second propylene polymer may be uniformly mixed in the cross section of the composite fiber or may be arranged so as to substantially occupy their respective regions and extend continuously along the longitudinal direction, and at least one of the first propylene polymer and the second propylene polymer may be continuous along the longitudinal direction of the composite fiber and form at least a portion of the peripheral surface.

[0034] The first propylene polymer and the second propylene polymer are each independently a propylene homopolymer or a copolymer of propylene having propylene as a main structural unit and one or more α-olefins having 2 to 20 carbon atoms, preferably 2 to 8 carbon atoms, such as ethylene, 1-butene, 1-pentene, 1-hexene, 1-octene, and 4-methyl-1-pentene. For example, the first propylene polymer and the second propylene polymer are each independently a propylene homopolymer or a propylene-ethylene random copolymer having an ethylene unit content of 0 to 10 mol% and an MFR of 20 to 200 g / 10 min.

[0035] In particular, in order to obtain a nonwoven fabric containing conjugate fibers having excellent bulk and good flexibility, the first propylene polymer may be a propylene homopolymer, and the second propylene polymer may be a random copolymer of propylene and a small amount of ethylene, with an ethylene unit content of 10 mol % or less, for example, 1 to 10 mol %. 13 It can be determined by a standard method using C-NMR spectroscopy.

[0036] The first propylene-based polymer further contains 1 to 5 wt % of a nucleating agent in addition to the propylene-based polymer component as the main component, and therefore the crystallization temperature of the first propylene-based polymer is 19°C or more higher than the crystallization temperature of the second propylene-based polymer.

[0037] The melting point of the first propylene polymer is in the range of 120 to 175° C., and the melting point of the second propylene polymer is in the range of 110 to 155° C. As described above, the difference in melting point between the two components is 30° C. or more, 30 to 60° C., or 30 to 100° C.

[0038] The nonwoven fabric may include 70 to 90 parts by weight of fibers formed by spinning the first propylene polymer and 10 to 30 parts by weight of fibers formed by spinning the second propylene polymer.

[0039] The hydrophilic agent may include a wax emulsion, a reactive softener, a silicon-based compound, a surfactant, or a combination thereof. The silicon-based compound may include an amino group-containing silicon, an oxyalkylene group-containing silicon, or a combination thereof. The surfactant may include anionic surfactants such as carboxylate-based anionic surfactants, sulfonate-based anionic surfactants, sulfate ester-based anionic surfactants, and phosphate ester-based anionic surfactants (particularly, alkyl phosphate ester salts); polyhydric alcohol mono-fatty acid esters such as sorbitan fatty acid esters, diethylene glycol monostearate, diethylene glycol monooleate, glyceryl monostearate, glyceryl monooleate, and propylen glycol monostearate; N-(3-oleyloxy-2-hydroxypropyl)diethanolamine, polyoxyethylene hydrogenated castor oil, polyoxyethylene sorbitol beeswax, polyoxyethylene nonionic surfactants such as ethylene sorbitan sesquistearate, polyoxyethylene monooleate, polyoxyethylene sorbitan sesquistearate, polyoxyethylene glyceryl monooleate, polyoxyethylene monostearate, polyoxyethylene monolaurate, polyoxyethylene monooleate, polyoxyethylene cetyl ether, polyoxyethylene lauryl ether; cationic surfactants such as quaternary ammonium salts, amine salts or amines; amphoteric surfactants such as aliphatic derivatives of secondary or tertiary amines, including carboxy, sulfonate, sulfate, or aliphatic derivatives of heterocyclic secondary or tertiary amines; or combinations thereof.

[0040] Specifically, the hydrophilic agent is a non-ionic hydrophilic agent.

[0041] The nonionic hydrophilic agent may include silicon compounds such as amino group-containing silicon and oxyalkylene group-containing silicon; polyhydric alcohol mono-fatty acid esters such as sorbitan fatty acid esters, diethylene glycol monostearate, diethylene glycol monooleate, glyceryl monostearate, glyceryl monooleate, and propylen glycol monostearate; nonionic surfactants such as N-(3-oleyloxy-2-hydroxypropyl)diethanolamine, polyoxyethylene hydrogenated castor oil, polyoxyethylene sorbitol beeswax, polyoxyethylene sorbitan sesquistearate, polyoxyethylene monooleate, polyoxyethylene sorbitan sesquistearate, polyoxyethylene glyceryl monooleate, polyoxyethylene monostearate, polyoxyethylene monolaurate, polyoxyethylene monooleate, polyoxyethylene cetyl ether, and polyoxyethylene lauryl ether; or combinations thereof.

[0042] More specifically, the nonionic hydrophilic agent may include a surfactant having a solid content of 90% by weight or more (ie, a nonionic surfactant).

[0043] In addition, the hydrophilic agent can be used in a kiss-roll method, in which an emulsion-type hydrophilic agent is applied to a rotating roll and then applied to a nonwoven fabric. By adjusting the rpm of the kiss-roll, the amount of hydrophilic agent (i.e., the solid component of the hydrophilic agent) adhered to the nonwoven fabric after drying (AOL: add-on level) can be adjusted.

[0044] The average diameter of the composite fibers is 1 to 50 μm.

[0045] The first propylene polymer and the second propylene polymer may be produced using a highly stereoregular polymerization catalyst.

[0046] The highly stereoregular polymerization catalyst may include a diester-based catalyst, a succinic acid-based catalyst, a metallocene catalyst, or a combination thereof.

[0047] Furthermore, when the first propylene-based polymer further contains the nucleating agent in addition to the propylene-based polymer component as the main component, the crystallization temperature of the first propylene-based polymer is increased and differentiated from the crystallization temperature of the second propylene-based polymer, thereby improving the thickness of the nonwoven fabric due to the development of crimp, and further improving the softness and bulkiness of the nonwoven fabric.

[0048] The nucleating agent may include a particulate additive, a self-assembling nucleating agent, a reactive nucleating agent, or a combination thereof. The particulate additive may include sodium benzoate, titanium dioxide, silica, nanoclay, sodium salt, calcium titanate, a metal oxide, a metal hydroxide, or a combination thereof. The self-assembling nucleating agent may include bis(p-methylbenzylidene)sorbitol, dibenzylidene sorbitol, monobenzylidene sorbitol (MBS), bis(p-methylbenzylidene)sorbitol, derivatives thereof, or combinations thereof. The reactive nucleating agent may include a metal salt, 4-biphenylcarboxylic acid, 4-biphenylmethanol, adipic acid, or a combination thereof.

[0049] The nonwoven fabric containing the conjugate fibers can be obtained by a normal conjugate melt spinning method without using any special equipment, and may be, for example, a spunbonded nonwoven fabric produced by a spunbonding method which has excellent productivity.

[0050] Hereinafter, a method for producing a nonwoven fabric according to one embodiment of the present invention will be described in detail.

[0051] A method for producing a nonwoven fabric according to one embodiment of the present invention may include the following steps:

[0052] (S10) melting the first propylene polymer, the second propylene polymer, and optionally one or more additives in separate sections in a single extruder or separate extruders at a temperature of 180 to 250°C to form a melt;

[0053] Step (S20) of discharging the melt through a spinneret having a single spinning nozzle or multiple spinning nozzles;

[0054] Step (S30) of cooling and stretching each of the extruded melts to form fibers;

[0055] (S40) collecting the formed fibers on a collecting belt and depositing them to a predetermined thickness to form a nonwoven fabric; and

[0056] A step (S50) of adding an emulsion-type hydrophilic agent to the formed nonwoven fabric.

[0057] The step (S30) is a step in which the composite fiber discharged from the step (S20) is cooled with cooling air and tensioned with drawing air to give the composite fiber a predetermined fineness.

[0058] In addition, the method of adding the emulsion-type hydrophilic agent to the formed nonwoven fabric in step (S50) is as described above.

[0059] In addition, the method for manufacturing a nonwoven fabric may further include a step (S45) between the steps (S40) and (S50) of imparting mechanical properties to the nonwoven fabric formed in the step (S40).

[0060] The step (S45) is carried out by a method using means such as needle punching, water jetting, or ultrasonic waves as the entanglement treatment, an embossing process using a heated embossing roll, or a method of heat sealing by high-temperature ventilation.

[0061] For example, the embossing has a bonding rate (i.e., embossed area rate) of 13% or less, and a non-embossed unit area of ​​0.2 mm 2 For example, 0.2 to 0.7 mm or more 2The non-embossed unit area herein means the maximum area of ​​a rectangle inscribed in the embossment in the smallest unit of non-embossed area surrounded on all four sides by embossed areas. If embossing is carried out under conditions within this range, a nonwoven fabric with greater bulkiness can be obtained while maintaining the required strength of the nonwoven fabric.

[0062] The bonding rate and non-embossed unit area can be adjusted by changing the embossing pattern.

[0063] As a result of the embossing process, the nonwoven fabric includes an embossed portion and a non-embossed portion, and the embossed portion may be an open embossed type and may include a plurality of unit embossed pattern portions continuously arranged at the same or different intervals.

[0064] In addition, each embossed pattern included in the unit embossed pattern portion has an area of ​​0.2 to 0.7 mm 2 is.

[0065] The nonwoven fabric of the composite fiber may further contain a fatty acid amide having 5 to 25 carbon atoms at a content of 0.01 to 3 wt % based on the total weight of the nonwoven fabric.

[0066] The fatty acid amide may act as a slip agent.

[0067] The fatty acid amides may include oleamide, erucamide, stearamide, or combinations thereof.

[0068] In addition to the first propylene polymer and the second propylene polymer, the composite fiber may contain other additives as needed within the scope of the present invention. The other additives may include known heat stabilizers, weather stabilizers, various stabilizers, antistatic agents, antiblocking agents, anticlouding agents, fillers, dyes, pigments, natural oils, synthetic oils, waxes, or combinations thereof.

[0069] The stabilizer may include an antioxidant such as 2,6-di-t-butyl-4-methylphenol (BHT), a phenolic antioxidant such as tetrakis[methylene-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionic acid]methane, β-(3,5-di-t-butyl-4-hydroxyphenyl)propionic acid alkyl ester, or 2,2′-oxamidobis[ethyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionic acid; a fatty acid metal salt such as zinc stearate, calcium stearate, or calcium 1,2-hydroxystearate; a polyhydric alcohol fatty acid ester such as glycerin monostearate, glycerin distearate, pentaerythritol monostearate, pentaerythritol distearate, or pentaerythritol tristearate; or a combination thereof.

[0070] The filler may include silica, diatomaceous earth, alumina, titanium oxide, magnesium oxide, pumice powder, pumice balloons, aluminum hydroxide, magnesium hydroxide, basic magnesium carbonate, dolomite, calcium sulfate, potassium titanate, barium sulfate, calcium sulfite, talc, clay, mica, asbestos, calcium silicate, montmorillonite, bentonite, graphite, aluminum powder, molybdenum sulfide, or a combination thereof.

[0071] The above-mentioned propylene-based polymer and the other additives used as needed can be mixed using a known method.

[0072] The nonwoven fabric may also be a spunbond nonwoven fabric.

[0073] The composite fiber is a mono-type, core / sheath type, side-by-side type, or sandwich type composite fiber in the form of a single fiber.

[0074] A nonwoven fabric laminate according to one embodiment of the present invention will be described in detail below.

[0075] A nonwoven fabric laminate according to one embodiment of the present invention is a laminate having a layer structure of at least two layers, at least one of which is the nonwoven fabric described above.

[0076] The nonwoven fabric laminate may include a spunbond nonwoven fabric among the above-mentioned nonwoven fabrics.

[0077] For example, the crimped composite fiber nonwoven fabric may be a spunbond nonwoven fabric, and the nonwoven fabric laminate may be configured such that the spunbond nonwoven fabric is exposed on only one of two surface layers.

[0078] The nonwoven fabric laminate may be formed by laminating four sheets of the spunbond nonwoven fabric, and in this case, the nonwoven fabric laminate has a uniformity (CV%) of 3% or less. In this specification, "uniformity (CV%)" refers to the uniformity of the nonwoven fabric laminate when it is spunbonded over 1 m. 2 After cutting the sample into 30 test pieces, the weight deviation of the 30 test pieces is divided by the average weight of the test pieces, and the weight deviation is expressed as a percentage.

[0079] The nonwoven fabric laminate formed by laminating four plies of the spunbond nonwoven fabric has a thickness of 0.02 mm or more, a crimp count of 10 or more per 10 mm, a bonding rate of 13% or less, and an MD stiffness (MD stiffness) indicating the softness of the nonwoven fabric laminate of 40 mm or less. In this specification, "MD stiffness" refers to the bending deformation in the machine direction of the nonwoven fabric laminate (i.e., the degree to which the nonwoven fabric laminate is bent).

[0080] An article according to one embodiment of the present invention will now be described in detail.

[0081] An article according to one embodiment of the present invention comprises the nonwoven laminate described above.

[0082] The article may be a diaper, an absorbent article, a disposable hygiene product, a toilet product, a side gather, a support layer or a top sheet.

[0083] The present invention will be described in more detail with reference to the following 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. [Example]

[0084] Example 1: Production of nonwoven fabric First, 88 parts by weight of the first propylene-based polymer and 12 parts by weight of the second propylene-based polymer were melted in separate sections in an extruder at temperatures between 180°C and 250°C to form a melt. The melt was then extruded through a spinneret with a single spinning nozzle. The extruded melt was then cooled with cooling air, and tension was applied with drawing air to form fibers with a predetermined fineness. The formed fibers were then collected on a collection belt and piled to a predetermined thickness to form a nonwoven fabric. Mechanical properties were then imparted to the formed nonwoven fabric by embossing using a heated embossing roll. The mechanically imparted nonwoven fabric was then surface-treated with a hydrophilic agent emulsion (i.e., an emulsion of 85 wt% water and 15 wt% sorbitan fatty acid ester) using a kiss roll method and dried by passing through a dryer at 130°C. As a result, a nonwoven fabric was obtained. The first propylene-based polymer is a propylene homopolymer (LG Chemical, H7700), and the second propylene-based polymer is an elastomeric random copolymer in which ethylene is copolymerized with polypropylene (Exxon Mobile Vistamaxx 7020, ethylene unit component content: 15.0 mol%). In this example, the polymer discharge rate, the line speed of the nonwoven fabric manufacturing apparatus, and the diameter per nozzle hole were adjusted to obtain a nonwoven fabric unit weight (g / m 2 ) specific surface area of ​​fiber (m 2 / m 2 ) to 0.24m 2 / g, the emulsion pick-up rate (EPU) of the hydrophilic agent was adjusted to 18 wt% based on the amount of emulsion applied to the nonwoven fabric, and the solid content (AOL) of the hydrophilic agent fixed to the nonwoven fabric after drying was adjusted to 0.45 wt%.

[0085] Example 2: Production of nonwoven fabric Unit weight of nonwoven fabric (g / m 2 ) specific surface area of ​​fiber (m 2 / m 2 ) to 0.20m 2 A nonwoven fabric was prepared in the same manner as in Example 1, except that the tensile strength was adjusted to 1 / g.

[0086] Example 3: Production of nonwoven fabric Unit weight of nonwoven fabric (g / m 2 ) specific surface area of ​​fiber (m 2 / m 2 ) to 0.28m 2 A nonwoven fabric was prepared in the same manner as in Example 1, except that the tensile strength was adjusted to 1 / g.

[0087] Example 4: Production of nonwoven fabric A nonwoven fabric was prepared in the same manner as in Example 1, except that the emulsion pick-up (EPU) of the hydrophilic agent was adjusted to 13 wt % based on the amount of emulsion applied to the nonwoven fabric.

[0088] Example 5: Production of nonwoven fabric A nonwoven fabric was prepared in the same manner as in Example 1, except that the emulsion pick-up (EPU) of the hydrophilic agent was adjusted to 23 wt % based on the amount of emulsion applied to the nonwoven fabric.

[0089] Example 6: Production of nonwoven fabric A nonwoven fabric was prepared in the same manner as in Example 1, except that the solid content (AOL) of the hydrophilic agent adhered to the nonwoven fabric after drying was adjusted to 0.3 wt %.

[0090] Example 7: Production of nonwoven fabric A nonwoven fabric was prepared in the same manner as in Example 1, except that the solid content (AOL) of the hydrophilic agent adhered to the nonwoven fabric after drying was adjusted to 0.6 wt %.

[0091] Comparative Example 1: Production of nonwoven fabric Unit weight of nonwoven fabric (g / m 2 ) specific surface area of ​​fiber (m 2 / m 2 ) to 0.18m 2 A nonwoven fabric was prepared in the same manner as in Example 1, except that the tensile strength was adjusted to 1 / g.

[0092] Comparative Example 2: Production of nonwoven fabric Unit weight of nonwoven fabric (g / m 2 ) specific surface area of ​​fiber (m 2 / m 2 ) to 0.30m 2 A nonwoven fabric was prepared in the same manner as in Example 1, except that the tensile strength was adjusted to 1 / g.

[0093] Comparative Example 3: Production of nonwoven fabric A nonwoven fabric was prepared in the same manner as in Example 1, except that the emulsion pick-up (EPU) of the hydrophilic agent was adjusted to 11.5 wt % based on the amount of emulsion applied to the nonwoven fabric.

[0094] Comparative Example 4: Production of nonwoven fabric A nonwoven fabric was prepared in the same manner as in Example 1, except that the emulsion pick-up (EPU) of the hydrophilic agent was adjusted to 25.5 wt % based on the amount of emulsion applied to the nonwoven fabric.

[0095] Comparative Example 5: Production of nonwoven fabric A nonwoven fabric was prepared in the same manner as in Example 1, except that the solid content (AOL) of the hydrophilic agent adhered to the nonwoven fabric after drying was adjusted to 0.2 wt %.

[0096] Comparative Example 6: Production of nonwoven fabric A nonwoven fabric was prepared in the same manner as in Example 1, except that the solid content (AOL) of the hydrophilic agent adhered to the nonwoven fabric after drying was adjusted to 0.7 wt %.

[0097] The manufacturing conditions of the nonwoven fabrics of Examples 1 to 7 and Comparative Examples 1 to 6, i.e., the unit weight (g / m 2 ) specific surface area of ​​fiber (m 2 / m 2 ), the emulsion pick-up rate (EPU) of the hydrophilic agent related to the amount of emulsion applied to the nonwoven fabric, and the solid content (AOL) of the hydrophilic agent fixed to the nonwoven fabric after drying are summarized in Table 1 below.

[0098] [Table 1]

[0099] Evaluation example: Evaluation of the physical properties of nonwoven fabric The physical properties of the nonwoven fabrics produced in Examples 1 to 7 and Comparative Examples 1 to 6 were evaluated by the following methods, and the results are shown in Table 2 below.

[0100] (1) Moisture content (wt%): Using an OHAUS MB-95 device, 16 nonwoven fabric samples were collected in a circular shape with a diameter of 80 mm. The 16 samples were placed in the device and set to 105°C and 1 mg / 60 seconds. When the lid was closed, the weight before drying was measured and drying began. The weight of the nonwoven fabric (weight after drying) was measured when there was no change of 1 mg for 60 seconds. Moisture percentage (%) = [(weight before drying) - (weight after drying)] / weight before drying x 100

[0101] (2) Unit weight of nonwoven fabric (g / m 2 ): Measured according to ASTM D 3776-1985.

[0102] (3) Fiber specific surface area (m 2 / m 2): The weight (gsm) and fiber diameter (μm) of the nonwoven fabric were measured. The weight was measured using WSP 130.1. The fiber diameter was measured using a SEM (Scanning Electron Microscope).

[0103] Fiber specific surface area (m 2 / m 2 ) = fiber diameter (μm) × 1,000,000 × π × fiber length (m / m 2 )

[0104] (4) Fiber specific surface area per unit weight of nonwoven fabric (m 2 / g): Fiber specific surface area (m ) measured in (3) above 2 / m 2 ) to the unit weight (g / m) of the nonwoven fabric measured in (2) above 2 ) was calculated by dividing it by

[0105] (5) Regurgitant volume (g): Measured using EDANA 151-02.

[0106] (6) Backflow rate per unit weight of nonwoven fabric (g / (g / m 2 )): The backflow amount (g) measured in (5) above is multiplied by the unit weight (g / m) of the nonwoven fabric measured in (2) above. 2 ) was calculated by dividing it by

[0107] (7) Static friction coefficient: The coefficient of friction was measured according to ISO8295. The measurement equipment used was a Friction Tester HM-3 manufactured by TOYOSEIKI. The measurement was performed under the conditions of a speed of 100 mm / min, a load cell of 10 N, and a sled of 200 g. During the measurement, both the dynamic and static friction coefficients were analyzed.

[0108] (8) Dynamic friction coefficient: The coefficient of friction was measured according to ISO 8295. The measurement equipment used was a Friction Tester HM-3 manufactured by TOYOSEIKI. The measurement was performed under the conditions of a speed of 100 mm / min, a load cell of 10 N, and a sled of 200 g. During the measurement, both the static and dynamic coefficients of friction were analyzed.

[0109] (9) Appearance: When the sparse and dense portions of the nonwoven fabric were clearly distinguishable by visual observation, it was rated as "poor," and when they were uniform, it was rated as "good."

[0110] (10) Coating uniformity: When the emulsion did not adhere well to the surface of the kiss roll and the nonwoven fabric was immersed in water, the wetted area of ​​the nonwoven fabric was easily visible to the naked eye, and the coating was evaluated as "good." When the nonwoven fabric had no wetted area, the coating was evaluated as "poor."

[0111] (11) Mold growth: When the nonwoven fabric was left in a hot and humid place (temperature: 30°C, relative humidity: 80%) for 6 months, it was confirmed by visual observation whether mold had grown on the surface and cross section of the roll.

[0112] (12) Absorption rate (sec): Absorption rate was measured by EDANA 150.3-96 using a Lenzing Model A-4860 instrument. Absorption rate of less than 5 seconds was evaluated as "good," and absorption rate of more than 5 seconds was evaluated as "poor."

[0113] [Table 2]

[0114] Furthermore, the required physical properties of a nonwoven fabric that meets the object of the present invention are shown in Table 3 below.

[0115] [Table 3]

[0116] Referring to Tables 2 and 3, it can be seen that the nonwoven fabrics prepared in Examples 1 to 7 satisfy all of the required physical properties of a nonwoven fabric consistent with the objectives of the present invention, while the nonwoven fabrics prepared in Comparative Examples 1 to 6 do not satisfy at least one of the required physical properties of a nonwoven fabric consistent with the objectives of the present invention.

[0117] Although the present invention has been described with reference to examples, these are merely illustrative, and those skilled in the art will recognize that various modifications and equivalent embodiments are possible. Therefore, the true technical scope of the present invention should be determined by the technical spirit of the appended claims.

Claims

1. Unit weight of nonwoven fabric (g / m ２ ) fiber specific surface area (m ２ / m ２ ) is 0.20 to 0.28 m ２ / g, The emulsion pick-up (EPU) of the hydrophilic agent applied to the nonwoven fabric is 13 to 23 wt %, A nonwoven fabric having a content (AOL: add-on level) of a hydrophilic agent fixed to the nonwoven fabric after drying of 0.3 to 0.6 wt % or less.

2. The nonwoven fabric has a unit weight (g / m ２ The reflux amount (g) per (g / m ２ 2. The nonwoven fabric according to claim 1, wherein

3. The nonwoven fabric according to claim 1 , wherein the nonwoven fabric has a moisture regain of 0.5 wt % or less.

4. 2. The nonwoven fabric according to claim 1, wherein the nonwoven fabric has a static friction coefficient of 0.350 to 0.430 and a dynamic friction coefficient of 0.300 to 0.

430.

5. A nonwoven fabric laminate having a layer structure of at least two layers, at least one of which is the nonwoven fabric according to any one of claims 1 to 4.

6. The nonwoven fabric is a spunbond nonwoven fabric, The nonwoven fabric laminate according to claim 5 , wherein the nonwoven fabric laminate is configured such that the spunbond nonwoven fabric is exposed on only one of the two surface layers.

7. An article comprising the nonwoven laminate of claim 5.

8. 8. The article of claim 7, wherein the article is a diaper, an absorbent article, a disposable hygiene product, a toileting product, a side gather, a support layer, or a top sheet.

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