Laminated article of nonwoven fabric of crimped composite fiber and article comprising the same

Abstract

This invention relates to laminated articles of nonwoven fabrics made of crimped composite fibers and articles comprising such laminated articles. This invention provides a nonwoven laminate comprising at least two layers, wherein at least one layer of the laminate comprises a nonwoven fabric of crimped composite fibers, the crimped composite fibers comprising: a first propylene polymer and a second propylene polymer, wherein the melting point of the second propylene polymer is 30°C or more higher than that of the first propylene polymer, the melting point being measured by differential scanning calorimetry (DSC), the melt flow rate (MFR: measurement temperature 230°C, load 2.16 kg) ratio (second polymer / first polymer) of the first and second propylene polymers is 1.7 or greater, the melt flow rate being measured according to ASTM D1238, and the component ratio expressed as the weight ratio of the first propylene polymer / second propylene polymer is 50 / 50 to 10 / 90, wherein the nonwoven fabric has a thickness of 0.484 mm or greater, 10 EA / 10 The curl count is 50 mm or greater, and the longitudinal (MD) stiffness is 50 mm or less in the adhesive area of ​​the embossed pattern.

Description

[0001] This application is a divisional application. The international application number of the original application is PCT / KR2019 / 004037, the application date is April 5, 2019, the Chinese national phase application number is 201980026780.8, and the invention title is "Nonwoven fabric of crimped composite fibers and laminated articles thereof, and articles comprising the laminated articles". Technical Field

[0002] One or more embodiments relate to a nonwoven fabric of a crimped composite fiber and its laminated articles and articles comprising the laminated articles, and more particularly to a nonwoven fabric of a crimped composite fiber having improved softness and bulkiness and its laminated articles and articles comprising the laminated articles.

[0003] This application claims the benefit of Korean Patent Application No. 10-2018-0044536, filed on April 17, 2018, with the Korean Intellectual Property Office, the full disclosure of which is incorporated herein by reference. Background Technology

[0004] The final physical properties of a nonwoven fabric are determined based on a web forming method and an bonding method.

[0005] In the production of conventional spunbond nonwoven fabrics, a web is formed by single spinning or core-sheath composite spinning. The web formed in this way has a simple structure without curling, and is bonded together with each other by a heating calender to form a thin nonwoven fabric.

[0006] During the production of a diaper, a thin nonwoven fabric is used as a top sheet and a back sheet. However, compared with a short-fiber breathable nonwoven fabric obtained by carding to form a web and bonding the web with hot air, this thin nonwoven fabric has very low softness, and therefore the softness of the thin nonwoven fabric is degraded.

[0007] Furthermore, because the mesh is not rolled up during diaper production, the bulkiness deteriorates, resulting in a larger area directly in contact with the baby's buttocks. Additionally, the lack of space between the ADL (Adaptive Distribution Layer) layers during nonwoven fabric lamination causes urine to remain in a portion of the top layer when the baby urinates, potentially leading to sores or rashes on the baby's buttocks. There is also the problem of urine leakage to the outside of the diaper. Summary of the Invention

[0008] Technical issues

[0009] One or more embodiments provide a nonwoven fabric of crimped composite fibers with improved softness and bulkiness.

[0010] One or more embodiments provide a nonwoven laminate comprising two or more nonwoven fabrics containing crimped composite fibers.

[0011] One or more embodiments provide an article comprising a nonwoven laminate.

[0012] Technical solution

[0013] Additional features will be set forth in part in the description below, and in part will be self-evident or may be learned by practicing the embodiments presented.

[0014] According to one or more embodiments, a nonwoven fabric of crimped composite fibers comprises: a first propylene polymer and a second propylene polymer, wherein the melting point of the second propylene polymer is 30°C or more higher than the melting point of one of the first propylene polymers, the melting points being measured by differential scanning calorimetry (DSC), the ratio (second polymer / first polymer) of the melt flow rate (MFR: measurement temperature 230°C, load 2.16 kg) of the first propylene polymer and the second propylene polymer is 1.7 or greater, the melt flow rate being measured according to ASTM D1238, and the component ratio, expressed by the weight ratio of the first propylene polymer / the second propylene polymer, is from 50 / 50 to 10 / 90.

[0015] The first propylene polymer and the second propylene polymer may each independently comprise a propylene homopolymer, a propylene-ethylene copolymer, an elastic random copolymer of ethylene and polypropylene, a propylene-ethylene-butene terpolymer, or a combination thereof.

[0016] The nonwoven fabric may further comprise a fatty acid amide of 5 to 25 carbon atoms in an amount of about 0.01 wt% to about 3 wt% of the total weight of the nonwoven fabric.

[0017] The nonwoven fabric may include an embossed portion and a non-embossed portion, and the embossed portion may be an open embossed portion and include a plurality of unit embossed pattern portions arranged continuously at the same or different intervals.

[0018] Each of these embossed pattern units may contain an embossed pattern of approximately 0.2 mm. 2 To approximately 0.7mm 2 One of the areas.

[0019] The nonwoven fabric may have an adhesion rate of 13% or less.

[0020] Crimped composite fibers can be single-type composite fibers, core-sheath type composite fibers, parallel type composite fibers, or sandwich type composite fibers.

[0021] The nonwoven fabric can be a spunbond nonwoven fabric.

[0022] According to one or more embodiments, a nonwoven laminate has at least two layers, wherein at least one layer of the laminate is a nonwoven fabric of crimped composite fibers.

[0023] The nonwoven fabric may be a spunbond nonwoven fabric, and the nonwoven laminate may be formed by laminating four spunbond nonwoven fabrics and have a uniformity (CV) of 3% or less.

[0024] Nonwoven laminates may have a thickness of 0.02 mm or greater, a crimp of 10 EA / 10 mm or greater, and an adhesion ratio of 13% or less, and a longitudinal (machine direction) stiffness of 50 mm or less in the adhesive area of ​​each embossed pattern.

[0025] According to one or more embodiments, an article comprises the nonwoven laminate.

[0026] The item may be a diaper, an absorbent item, a waste disposal item, a support layer, or a top sheet.

[0027] When the article is a diaper, the nonwoven laminate may have an OPU of 0.7% or less, and therefore when the nonwoven laminate is applied to a top layer of the diaper, the article may have an absorbency of 3 seconds or less.

[0028] Beneficial effects

[0029] As described above, in the nonwoven fabric of the crimped composite fiber according to one embodiment, the crimped shape is clear and the crimped shape stability is good, which improves softness and bulkiness.

[0030] Therefore, a diaper containing nonwoven fabric with crimped composite fibers will not harm a wearer's skin or cause rashes. Attached Figure Description

[0031] These and / or other variations will become apparent and more readily understood from the following description of the embodiments, taken in conjunction with the accompanying drawings, wherein: Figure 1 This is a partial view showing an embossed pattern of a nonwoven fabric made of a type of crimped composite fiber, according to one embodiment of the present invention; Figure 2 A cross-sectional view of the crimped composite fibers used in the examples and comparative examples; Figure 3 This is a partial view of an embossed pattern of one of the nonwoven fabrics made from one of the crimped composite fibers prepared in Example 4. Detailed Implementation

[0032] Detailed reference will now be made to embodiments, examples of which are illustrated in the accompanying drawings, wherein similar element symbols throughout refer to similar elements. In this regard, embodiments may take different forms and should not be construed as limited to the description set forth herein. Accordingly, the embodiments described below are merely illustrated with reference to the figures to explain the nature of this description. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. Expressions preceding a list of elements (such as "at least one of") modify the entire list of elements and do not modify individual elements of the list.

[0033] The following section will describe in detail one of the nonwoven fabrics of crimped composite fibers according to one embodiment.

[0034] According to one embodiment, a nonwoven fabric of a crimped composite fiber (hereinafter referred to as "composite fiber") comprises a first acrylic polymer and a second acrylic polymer.

[0035] In the first propylene polymer and the second propylene polymer, (i) the melting point of the second propylene polymer is 30°C or more higher than that of one of the first propylene polymers, and these melting points are measured by differential scanning calorimetry (DSC); (ii) the ratio of the melt flow rate (MFR: measured at 230°C and a load of 2.16 kg) of the first propylene polymer and the second propylene polymer (second polymer / first polymer) is 1.7 or greater, and these melt flow rates are measured according to ASTM D1238; and (iii) the component ratio, expressed by the weight ratio of the first propylene polymer to the second propylene polymer, is between 50 / 50 and 10 / 90.

[0036] For example, the melting point of the second propylene polymer may be about 30°C to about 60°C or about 30°C to about 100°C higher than that of the first propylene polymer.

[0037] For example, the melt flow ratio (second polymer / first polymer) may be from about 1.7 to about 2.0, from about 1.7 to about 3.0, or from about 1.7 to about 4.0.

[0038] When the first propylene polymer and the second propylene polymer satisfy all of the above conditions (i) to (iii), the composite fiber has crimping properties, and therefore the nonwoven fabric containing the composite fiber can have good softness and bulkiness.

[0039] The first and second propylene polymers are configured to occupy substantially their respective regions in the cross-section of the composite fiber and are continuously stretched along a length direction. At least one component of the first and second propylene polymers may continuously form at least a portion of a peripheral surface along the length direction of the composite fiber.

[0040] The first propylene polymer and the second propylene polymer may each independently comprise a propylene homopolymer, a propylene-ethylene random copolymer, an elastic random copolymer of ethylene and polypropylene, a propylene-ethylene-butene terpolymer, or a combination thereof.

[0041] Propylene-ethylene random copolymers can have an ethylene unit component content of about 10 mol% to about 30 mol% and a melt flow rate (MFR) of about 10 g / 10 min to about 200 g / 10 min. Through 13 C-NMR spectroscopy was used to determine the content of ethylene unit components.

[0042] For example, the elastic random copolymer may be included in the first propylene polymer in an amount of about 10 wt% to about 30 wt%.

[0043] As another example, the propylene-ethylene-butene terpolymer may be included in the first propylene polymer in an amount of about 10 wt% to about 30 wt%.

[0044] As another example, the elastic random copolymer and the propylene-ethylene-butene terpolymer may be included in the first propylene polymer in an amount of about 10 wt% to about 30 wt%.

[0045] In detail, at least one component of the first propylene polymer and the second propylene polymer may comprise a propylene homopolymer; wherein propylene is a copolymer of at least one of an α-olefin (such as ethylene, 1-butene, 1-pentene, 1-hexene, 1-octene and 4-methyl-1-pentene) having 2 to 20 carbon atoms (e.g., 2 to 8 carbon atoms); or a combination thereof.

[0046] For obtaining a nonwoven fabric of composite fibers with good softness and bulkiness, the first propylene polymer may be a mixture of 70 wt% to 90 wt% of propylene homopolymer and 10 wt% to 30 wt% of elastic random copolymer or propylene-ethylene-butene terpolymer, and the second propylene polymer may be a propylene homopolymer.

[0047] The melting point of the second propylene polymer may be in the range of about 120°C to about 175°C, and the melting point of the first propylene polymer may be in the range of about 110°C to about 155°C. As described above, the difference in melting points between the two polymers may be in the range of 30°C or higher, about 30°C to about 60°C, or about 30°C to about 100°C.

[0048] The aforementioned propylene polymers can be prepared using highly stereoregular polymerization catalysts.

[0049] Highly stereoregular polymerization catalysts may include diester-based catalysts, succinate-based catalysts, metallocene catalysts, or combinations thereof.

[0050] Nonwoven fabrics containing composite fibers can be obtained using conventional composite melt spinning methods without the need for a special device. For example, the nonwoven fabric can be a spunbond nonwoven fabric prepared using a spunbond method that exhibits high productivity.

[0051] A method for producing a spunbond nonwoven fabric will be described in detail later.

[0052] First, a first propylene polymer forming one region of a composite fiber and a second propylene polymer forming another region of a composite fiber are melted by two extruders or similar means, and the melts are discharged from a spinning nozzle having a composite spinning nozzle designed to form and discharge a desired fiber structure to discharge composite long fibers.

[0053] Next, the discharged long fibers are cooled by cooling air, and a tension is applied to the cooled long fibers by air to stretch them to allow the long fibers to have a predetermined fineness. The stretched long fibers are then collected directly on a collection belt and deposited to a predetermined thickness.

[0054] Next, the process is performed as a post-mixing treatment by means of a needle punch, a water jet, an ultrasonic or similar method; an embossing process using a heated embossing roller; or a hot melting method using hot ventilated air.

[0055] In one embodiment of the present invention, nonwoven fabric can be formed by using embossing and hot melting.

[0056] It can achieve an adhesion ratio of 13% or less (i.e., embossing area ratio) and 0.2mm. 2 Or larger (e.g., about 0.2 mm) 2 To approximately 0.7mm 2 Embossing is performed under conditions where the non-embossed unit area is within a certain range. Here, the non-embossed unit area refers to the largest area of ​​a rectangle that contacts the inner side of one of the smallest units of the non-embossed portion that is surrounded by embossed portions on all sides. When embossing is performed under these conditions, a nonwoven fabric with better bulkiness while maintaining the necessary strength can be obtained.

[0057] The adhesion rate and non-embossed unit area can be adjusted by changing an embossed pattern.

[0058] As a result of the embossing process, the nonwoven fabric may include an embossed portion and a non-embossed portion, and the embossed portion may be an open embossed portion and include a plurality of unit embossed pattern portions arranged continuously at the same or different intervals.

[0059] The fineness and basic weight of the nonwoven fabric can be appropriately selected depending on the application. Typically, the fineness of the nonwoven fabric can be from about 1.0 denier to about 2.5 denier, for example, from about 0.7 denier to about 2.0 denier, and the basic weight of the nonwoven fabric can be about 15 g / m². 2 Approximately 100g / m 2 For example, about 7g / m 2 Approximately 30g / m 2 .

[0060] Each embossed pattern within a unit of embossed pattern may have a diameter of approximately 0.2mm. 2 To approximately 0.7mm 2 One of the areas.

[0061] The nonwoven fabric further comprises a fatty acid amide of 5 to 25 carbon atoms in an amount of about 0.01 wt% to about 3 wt% of the total weight of the nonwoven fabric.

[0062] Fatty acid amides can be used as lubricants.

[0063] Fatty acid amides may include oleamide, erucamide, stearamide, or a combination thereof.

[0064] In addition to the first and second propylene polymers, the composite fiber may also contain other components as needed, provided that this does not impair one of the objectives of the present invention. Examples of other components may include a heat stabilizer, a weather stabilizer, various stabilizers, an antistatic agent, an anti-clogging agent, an anti-fogging agent, a filler, a dye, a pigment, natural oils, synthetic oils, waxes, and combinations thereof.

[0065] The stabilizer may contain an anti-aging agent, such as 2,6-di-tert-butyl-4-methylphenol (BHT); a phenolic antioxidant, such as tetra[methylene-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]methane, alkyl ester of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, or 2,2'-oxalamide bis[ethyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]; a fatty acid metal salt, such as zinc stearate, calcium stearate, or calcium 1,2-hydroxystearate; a polyol fatty acid ester, such as glyceryl monostearate, glyceryl distearate, pentaerythritol monostearate, pentaerythritol distearate, or pentaerythritol tristearate; or a combination thereof.

[0066] The filler may contain silica, diatomaceous earth, alumina, titanium dioxide, magnesium oxide, pumice powder, pumice balls, 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.

[0067] The aforementioned propylene polymer and other aforementioned components to be used as needed can be mixed by a known method.

[0068] Composite fibers can be single-type composite fibers, core-sheath type composite fibers, parallel type composite fibers, or sandwich type composite fibers.

[0069] The nonwoven laminate article according to one embodiment of the present invention will be described in detail below.

[0070] According to one embodiment of the present invention, the nonwoven laminate article may be a laminate article having at least two layers. Here, at least one layer of the laminate article may be the aforementioned nonwoven fabric.

[0071] Nonwoven laminates may include one of the aforementioned nonwoven fabrics, spunbond nonwoven fabric.

[0072] Nonwoven laminates can be formed by laminating four spunbond nonwoven fabrics. In this case, the nonwoven laminate can have a uniformity (CV) of 3% or less. In this specification, "uniformity (CV%)" refers to the uniformity when the nonwoven laminate is cut into 1m... 2 The size is a percentage of the value obtained by dividing the weight deviation of one of the 30 test samples by the average weight of one of the 30 test samples after making 30 test samples.

[0073] Nonwoven laminates formed by laminating four spunbond nonwoven fabrics can have a thickness of 0.02 mm or greater, a crimp count of 10 EA / 10 mm or greater, and a bonding rate of 13% or less, and can have a longitudinal (MD) stiffness of 40 mm or less, which indicates the softness of the nonwoven laminate. In this specification, "MD stiffness" refers to the flexural deformation of the nonwoven laminate in a longitudinal direction (i.e., the degree of warping of the nonwoven laminate).

[0074] The article according to one embodiment of the present invention will be described in detail below.

[0075] An article according to one embodiment of the present invention comprises the aforementioned nonwoven laminate.

[0076] The item may be a diaper, an absorbent material, a waste disposal material, a support layer, or a top sheet.

[0077] When the article is a diaper, the nonwoven laminate has a hydrophilic agent impregnation amount (OPU: oil pick-up) of 0.7% or less, and therefore when the nonwoven laminate is applied to one of the top layers of the diaper, the article can have an absorbency of 3 seconds or less.

[0078] The hydrophilic agent impregnation amount (OPU) can be calculated according to Equation 1 below.

[0079] [Equation 1]

[0080] OPU(%)=(W1-W0) / W0x100

[0081] In Equation 1, W0 is the weight of a nonwoven laminate without the hydrophilic agent, and W1 is the weight of a nonwoven laminate containing the hydrophilic agent. In the impregnation process, the hydrophilic agent is used as an aqueous suspension of polydimethylsiloxane having a concentration of 15 wt%. However, in Equation 1, the weight of the hydrophilic agent contained in the nonwoven laminate refers only to the weight of the solid component.

[0082] The invention will be described in more detail below through examples. The examples described below are intended to illustrate the invention in more detail, but the scope of the invention is not limited to these examples.

[0083] Examples 1 to 6 and Comparative Examples 1 to 5

[0084] The first propylene polymer (A), containing one of the erucic acid amide lubricants, and the second propylene polymer (B), containing one of the erucic acid amide lubricants, are subjected to composite melt spinning via a spunbond method to achieve the desired properties. Figure 2 The composite fibers of the structure are deposited side-by-side on a collection surface, and the composite fibers are subjected to a process using a calender roll (the upper part of which is heated to 146°C and the lower part to 144°C). Figure 1 The embossing process shown in the figure involves embossing the pattern to produce a nonwoven fabric containing crimped composite fibers. Table 1 below provides the type, physical properties, and content ratio of the first acrylic polymer (A) and the second acrylic polymer (B), the amount of erucamide lubricant, and the characteristics of the embossing pattern. In the table, MFR refers to the melt index measured according to ASTM D1238 at a temperature of 230°C and a load of 2.16 kg, and the lubricant amount refers to the weight relative to the total weight of the nonwoven fabric.

[0085] [Table 1]

[0086] In Table 1, PA1 to PA7 and PB are as follows.

[0087] (1) PA1: A mixture of 70 wt% propylene homopolymer (H7700, manufactured by LG Chem.) and 30 wt% elastic random copolymer (T-7700, manufactured by LG Chem.), wherein ethylene is copolymerized with polypropylene.

[0088] (2) PA2: A mixture of 60 wt% propylene homopolymer (H7700, manufactured by LG Chem.) and 40 wt% elastic random copolymer (VISTAMAXX 7020, manufactured by EXXON), wherein ethylene is copolymerized with polypropylene.

[0089] (3) PA3: A mixture of 40 wt% propylene homopolymer (H7700, manufactured by LG Chem.) and 60 wt% elastic random copolymer (VERSIFY 4200, manufactured by DOW), wherein ethylene is copolymerized with polypropylene.

[0090] (4) PA4: A mixture of 70 wt% propylene homopolymer (H7700, manufactured by LG Chem.) and 30 wt% elastic random copolymer (T-7700, manufactured by LG Chem.), wherein ethylene is copolymerized with polypropylene.

[0091] (5) PA5: A mixture of 70 wt% propylene homopolymer (MH7700, manufactured by LG Chem.) and 30 wt% elastic random copolymer (T-7700, manufactured by LG Chem.), wherein ethylene is copolymerized with polypropylene.

[0092] (6) PA6: A mixture of 60 wt% propylene homopolymer (MH7700, manufactured by LG Chem.) and 40 wt% elastic random copolymer (T-7700, manufactured by LG Chem.), wherein ethylene is copolymerized with polypropylene.

[0093] (7) PA7: A mixture of 70 wt% propylene homopolymer (H7700, manufactured by LG Chem.) and 30 wt% elastic random copolymer (T-7700, manufactured by LG Chem.), wherein ethylene is copolymerized with polypropylene.

[0094] (8) PB: Propylene homopolymer (H562T, manufactured by PMC)

[0095] Evaluation Example 1: Evaluation of the Physical Properties of Spunbond Nonwoven Fabric

[0096] The physical properties of the spunbond nonwoven fabrics prepared in Examples 1 to 6 and Comparative Examples 1 to 5 are evaluated as follows, and the results are given in Table 2 below.

[0097] (1) Measure the weight per unit area (g / m²) according to ASTM D 3776-1985. 2 ).

[0098] (2) Tensile strength: The maximum tensile load is obtained by performing a tensile test using a tensile strength measuring device (Instron) according to KSK 0520 under the conditions of a test sample width of 5 cm, a test sample interval of 10 cm and a tensile speed of 500 mm / min.

[0099] (3) Tensile elongation: When the nonwoven fabric is stretched to its maximum value, the elongation is measured by the above method (2).

[0100] (4) Measure the thickness (mm) according to KSK 0506.

[0101] (5) Number of curls: The number of curls of the filaments within a 10 mm range is directly measured using a microscope.

[0102] (6) Spinability: The vibration of the filaments is visually observed during melt spinning, and polymer dripping is detected by a defect detector.

[0103] [Table 2]

[0104] Referring to Table 2, it was found that, compared with the nonwoven fabrics prepared in Examples 1 to 5, the nonwoven fabrics of crimped composite fibers prepared in Examples 1 to 6 were thicker, had a large amount of crimp, and had good or similar other physical properties, such as tensile strength (MD: longitudinal), tensile strength (CD: transverse), elongation at break (MD: longitudinal), elongation at break (CD: transverse), and spinnability.

[0105] Figure 3 This is a partial view of one of the embossed patterns of the nonwoven fabric made of crimped composite fibers prepared in Example 4.

[0106] refer to Figure 3 It was found that the nonwoven fabric of the crimped composite fiber prepared in Example 4 had a crimp count of approximately 20 / 10 mm.

[0107] Evaluation Example 2: Evaluation of the physical properties of nonwoven laminates containing spunbond nonwoven fabric

[0108] The spunbond nonwoven fabrics prepared in Examples 1 to 6 and Comparative Examples 1 to 5 were laminated in four layers to produce nonwoven laminate articles. The physical properties of each nonwoven laminate article were then evaluated using the methods described below, and the results are given in Table 3 below.

[0109] (1) Uniformity (CV%) is determined by cutting the nonwoven laminate into 1m pieces. 2 The uniformity is evaluated as a percentage of the weight deviation of one of the 30 test samples divided by the average weight of the 30 test samples after making 30 test samples. The smaller the uniformity (CV%) value, the better the uniformity.

[0110] (2) Measure the thickness (mm) according to KSK 0506.

[0111] (3) Number of curls: The number of curls of the filaments in a range of 10 mm is directly measured using a microscope.

[0112] (4) Adhesion rate (%) refers to the percentage of heat transferred to the nonwoven fabric as part of the embossed part of an embossed pattern.

[0113] (5) MD stiffness (mm): The bending distance of a nonwoven laminate sample when it is brought into contact with an inclined surface by a tester with an inclination of 45°. The smaller the MD stiffness, the better the flexibility.

[0114] (6) OPU (oil content) is obtained by calculating the amount of hydrophilic agent (i.e., solid content) sprayed onto the nonwoven laminate as a percentage of the total weight.

[0115] (7) Water absorption rate: When artificial urine is dropped onto a nonwoven laminate according to EDANA 150.5 (02), the time it takes for the artificial urine to pass through the nonwoven laminate is measured by a sensor.

[0116] [Table 3]

[0117] Referring to Table 3, it was found that, compared with the nonwoven laminates produced from the four nonwoven fabrics of the crimped composite fibers prepared in Comparative Examples 1 to 5, the nonwoven laminates produced from the four nonwoven fabrics of the crimped composite fibers prepared in Comparative Examples 1 to 6 have a good uniformity of 3% or less, are thick, have a large amount of crimp, have a small MD stiffness, have a similar OPU, and have a fast water absorption rate.

[0118] As described above, in the nonwoven fabric of the crimped composite fiber according to one embodiment, the crimped shape is clear and the crimped shape stability is good, which improves softness and bulkiness.

[0119] Therefore, a diaper containing nonwoven fabric with crimped composite fibers will not harm a wearer's skin or cause rashes.

[0120] It should be understood that the embodiments described herein are to be considered descriptive in nature only and not for limiting purposes. The descriptions of features or mannerisms within each embodiment should generally be considered applicable to other similar features or mannerisms in other embodiments.

[0121] Although one or more embodiments have been described with reference to the figures, those skilled in the art will understand that various changes in form and detail may be made without departing from the spirit and scope of the invention as defined by the claims below.

Claims

1. A nonwoven laminate comprising at least two layers, wherein at least one layer of the laminate comprises a nonwoven fabric of crimped composite fibers, the crimped composite fibers comprising: a first propylene-based polymer and a second propylene-based polymer, wherein, in the first propylene-based polymer and the second propylene-based polymer, the melting point of the second propylene-based polymer is 30°C or more higher than the melting point of the first propylene-based polymer, the melting point is measured by differential scanning calorimetry (DSC), the ratio (second polymer / first polymer) of the melt flow rate (MFR: measurement temperature 230°C, load 2.16 kg) of the first propylene-based polymer and the second propylene-based polymer is 1.7 or more, the melt flow rate is measured according to ASTM D1238, and the component ratio represented by the weight ratio of the first propylene-based polymer / the second propylene-based polymer is 50 / 50 to 10 / 90, wherein the nonwoven fabric has a thickness of 0.484 mm or more, a crimp number of 10 EA / 10 mm or more, and a machine direction (MD) stiffness of 50 mm or less in the bonded area of the embossed pattern.

2. The nonwoven laminate of claim 1, wherein the first propylene-based polymer and the second propylene-based polymer each independently comprise a propylene homopolymer, a propylene-ethylene copolymer, an elastic random copolymer in which ethylene is copolymerized with polypropylene, a propylene-ethylene-butene terpolymer, or a combination thereof.

3. The nonwoven laminate of claim 1, wherein the nonwoven fabric further comprises a fatty acid amide of 5 to 25 carbon atoms in an amount of 0.01 to 3 wt% based on the total weight of the nonwoven fabric.

4. The nonwoven laminate of claim 1, wherein the nonwoven fabric comprises an embossed portion and a non-embossed portion, and the embossed portion is an open embossed portion and comprises a plurality of unit embossed pattern portions continuously arranged at the same or different intervals.

5. The nonwoven laminate of claim 4, wherein each of the embossed patterns contained in the unit embossed pattern section has an area of about 0.2 mm 2 to about 0.7 mm 2 .

6. The nonwoven laminate of claim 4, wherein the nonwoven fabric has a bonding rate of 13% or less.

7. The nonwoven laminate of claim 1, wherein the crimped composite fiber is a unimode composite fiber, a core-sheath type composite fiber, a side-by-side type composite fiber, or a sandwich type composite fiber.

8. The nonwoven laminate of claim 1, wherein the nonwoven fabric is a spunbond nonwoven fabric.

9. The nonwoven laminate of claim 1, wherein the nonwoven fabric is a spunbond nonwoven fabric, and the nonwoven laminate is formed by laminating four spunbond nonwoven fabrics and has a uniformity (CV) of 3% or less.

10. An article comprising the nonwoven laminate of any one of claims 1 to 9.

11. The article of claim 10, wherein the article is a diaper, an absorbent article, a feces management article, a support layer, or a topsheet.

12. The article of claim 11, When the article is a diaper, the nonwoven laminate has an OPU of 0.7% or less, and therefore when the nonwoven laminate is applied to the top layer of the diaper, the article has an absorption rate of 3 seconds or less.

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