CN112074632A

CN112074632A - Nonwoven fabric of crimped conjugate fiber, laminate thereof, and article comprising the laminate

Info

Publication number: CN112074632A
Application number: CN201980026780.8A
Authority: CN
Inventors: 郑镇一; 徐永锡; 金大熙; 安重权
Original assignee: Toray Advanced Materials Korea Inc
Current assignee: Toray Advanced Materials Korea Inc
Priority date: 2018-04-17
Filing date: 2019-04-05
Publication date: 2020-12-11
Also published as: KR102036763B1; JP2021518886A; TW201945457A; TWI742363B; JP7221987B2; WO2019203484A1

Abstract

The present invention provides a non-woven fabric of crimped composite fibers, which comprises: a first propylene-based polymer and a second propylene-based polymer, wherein in the first propylene-based polymer and the second propylene-based polymer, a melting point of the first propylene-based polymer is higher than a melting point of the second propylene-based polymer by 30 ℃ or more, a ratio (second polymer/first polymer) of melt flow rates (MFR: measured temperature 230 ℃, load 2.16kg) of the first propylene-based polymer and the second propylene-based polymer is 1.7 or more, and a component ratio represented by a weight ratio of the first propylene-based polymer/the second propylene-based polymer is 50/50 to 10/90.

Description

Nonwoven fabric of crimped conjugate fiber, laminate thereof, and article comprising the laminate

Technical Field

One or more embodiments relate to a nonwoven fabric of crimped conjugated fibers and a laminate thereof and an article comprising the laminate, and more particularly, to a nonwoven fabric of crimped conjugated fibers having improved softness and bulkiness and a laminate thereof and an article comprising the laminate.

This application claims the benefit of korean patent application No. 10-2018-0044536, filed by the korean intellectual property office at 17.4.2018, the disclosure of which is incorporated herein by reference in its entirety.

Background

The final physical properties of a nonwoven fabric are determined according to a web forming method and a bonding method.

In the production of a conventional spunbonded nonwoven fabric, webs are formed by single-spinning or core-sheath composite spinning. The webs formed in this way have a simple structure without curling and are bonded to each other by a heating calender (heating calender) to form a thin nonwoven fabric.

During the production of a diaper, the thin nonwoven fabric is used as a topsheet and a backsheet. However, this thin nonwoven fabric has very low softness compared to a short fiber air-permeable nonwoven fabric obtained by forming the web through carding and bonding the web through hot air, and thus the softness of the thin nonwoven fabric is deteriorated.

Further, since no curl is formed at the time of forming the web during the production of a diaper, so that bulkiness is deteriorated, an area directly contacting the hip skin of an infant is large, and there is no space between the Acquisition Distribution Layers (ADLs) when the nonwoven fabric is laminated, so that when an infant urinates, urine remains in a part of the topsheet, thereby ulcerating or causing a rash on the hip of the infant. In addition, there is a problem in that urine leaks to the outside of a diaper.

Disclosure of Invention

Technical problem

One or more embodiments provide a nonwoven fabric of crimped composite fibers having improved softness and bulkiness.

One or more embodiments provide a nonwoven fabric laminate comprising two or more nonwoven fabrics of crimped composite fibers.

One or more embodiments provide an article comprising a nonwoven fabric laminate.

Technical scheme

Additional aspects will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the presented embodiments.

According to one or more embodiments, a nonwoven fabric of crimped composite fibers comprises: 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 first propylene-based polymer has a melting point higher than a melting point of the second propylene-based polymer by 30 ℃ or more as measured by a Differential Scanning Calorimeter (DSC), a ratio (second polymer/first polymer) of melt flow rates (MFR: measurement temperature 230 ℃, 2.16kg load) of the first propylene-based polymer and the second propylene-based polymer is 1.7 or more, the melt flow rates are measured according to ASTM D1238, and a component ratio represented by a weight ratio of the first propylene-based polymer/the second propylene-based polymer is 50/50 to 10/90.

The first propylene-based polymer and the second propylene-based polymer may each independently comprise a propylene homopolymer, a propylene-ethylene copolymer, an elastomeric random copolymer in which ethylene is copolymerized with polypropylene, a propylene-ethylene-butylene terpolymer, or a combination thereof.

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%, based on a total weight of the nonwoven fabric.

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 in series at the same or different intervals.

Each of the plurality of unit embossing pattern portions has a shape of:

each of the embossing patterns included in each of the unit embossing pattern portions may have about 0.2mm²To about 0.7mm²An area of the substrate.

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

The crimped composite fiber can be a single-type composite fiber, a core-sheath type composite fiber, a side-by-side type composite fiber or a sandwich type composite fiber.

The nonwoven fabric may be a spunbonded nonwoven fabric.

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 of crimped composite fibers.

The nonwoven fabric may be a spunbonded nonwoven fabric, and the nonwoven fabric laminate may be formed by laminating four spunbonded nonwoven fabrics and has a uniformity (CV) of 3% or less.

The nonwoven fabric laminate may have a thickness of 0.02mm or more, a curl number of 10EA/10mm or more, and a bonding rate of 13% or less, and a Machine Direction (MD) stiffness of 50mm or less in a bonding region of each embossed pattern.

According to one or more embodiments, an article comprises the nonwoven fabric laminate.

The article may be a diaper, an absorbent article, a fecal article, a support layer or a topsheet.

When the article is a diaper, the nonwoven fabric laminate may have a hydrophilic agent impregnation amount (OPU) of 0.7% or less, and thus when the nonwoven fabric laminate is applied to a topsheet layer of the diaper, the article may have a water absorption speed of 3 seconds or less.

Advantageous effects

As described above, in the nonwoven fabric of crimped conjugated fibers according to an embodiment, the shape of the crimp is clear and the shape stability of the crimp is good, so that softness and bulkiness can be improved.

Thus, a diaper comprising the crimped conjugated fiber nonwoven fabric does not damage the skin of a wearer or cause rash.

Drawings

These and/or other aspects will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a partial view showing an embossing pattern of a nonwoven fabric of crimped conjugated fibers according to an embodiment of the present invention;

FIG. 2 is a cross-sectional view of a crimped composite fiber used in examples and comparative examples;

FIG. 3 is a partial view showing an embossing pattern of a nonwoven fabric of crimped conjugated fiber prepared in example 4.

Detailed Description

Reference will now be made in detail to the embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. In this regard, the present embodiments may take different forms and should not be construed as limited to the description set forth herein. Accordingly, the embodiments are described below merely by way of explanation of aspects of the description with reference to the figures. 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.

Hereinafter, a non-woven fabric of crimped composite fibers according to an embodiment will be described in detail.

A nonwoven fabric of crimped conjugate fibers (hereinafter, simply referred to as "conjugate fibers") according to an embodiment includes a first propylene-based polymer and a second propylene-based polymer.

In the first propylene-based polymer and the second propylene-based polymer, (i) the first propylene-based polymer has a melting point higher than a melting point of the second propylene-based polymer by a Differential Scanning Calorimeter (DSC) by 30 ℃ or more, (ii) a ratio (second polymer/first polymer) of melt flow rates (MFR: measured temperature 230 ℃, load 2.16kg) of the first propylene-based polymer and the second propylene-based polymer, the melt flow rates being measured according to ASTM D1238, is 1.7 or more, and (iii) a component ratio represented by a weight ratio of the first propylene-based polymer/second propylene-based polymer is 50/50 to 10/90.

For example, the melting point of the first propylene-based polymer may be from about 30 ℃ to about 60 ℃ or from about 30 ℃ to about 100 ℃ higher than the melting point of the second propylene-based polymer.

For example, the ratio of melt flow rates (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.

When the first propylene-based polymer and the second propylene-based polymer satisfy all of the above conditions (i) to (iii), the composite fiber has crimpability, and thus the nonwoven fabric comprising the composite fiber can have good softness and bulkiness.

The first propylene-based polymer and the second propylene-based polymer are arranged to occupy substantially respective regions in a cross section of the composite fiber, and are continuously drawn in a length direction. At least one component of the first propylene-based polymer and the second propylene-based polymer may continuously form at least a part of a peripheral surface along the length direction of the conjugate fiber.

The first propylene-based polymer and the second propylene-based polymer may each independently comprise a propylene homopolymer, a propylene-ethylene random copolymer, an elastomeric random copolymer in which ethylene is copolymerized with polypropylene, a propylene-ethylene-butylene terpolymer, or a combination thereof.

The propylene-ethylene random copolymer may have an ethylene unit component content of about 10 mol% to about 30 mol% and a Melt Flow Rate (MFR) of about 10g/10min to about 200g/10 min. By means of¹³C-NMR spectroscopy was carried out to determine the content of the ethylene unit component.

For example, the elastomeric random copolymer may be included in the first propylene-based polymer in an amount of from about 10 wt% to about 30 wt%.

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

As another example, the elastomeric random copolymer and the propylene-ethylene-butene terpolymer may be included in the first propylene-based polymer in an amount from about 10 wt% to about 30 wt%.

In detail, at least one component of the first propylene-based polymer and the second propylene-based polymer may comprise a propylene homopolymer; copolymers in which propylene is copolymerized as a main structural element with at least one of alpha-olefins of 2 to 20 carbon atoms (e.g., 2 to 8 carbon atoms), such as ethylene, 1-butene, 1-pentene, 1-hexene, 1-octene and 4-methyl-1-pentene; or a combination thereof.

For a nonwoven fabric that obtains composite fibers with good softness and bulk, the first propylene-based polymer may be a mixture of 70 to 90 wt% of a propylene homopolymer and 10 to 30 wt% of an elastomeric random copolymer or a propylene-ethylene-butylene terpolymer, and the second propylene-based polymer may be a propylene homopolymer.

The melting point of the first propylene-based polymer may be in a range of about 120 ℃ to about 175 ℃, and the melting point of the second propylene-based polymer may be in a range of about 110 ℃ to about 155 ℃. As described above, the difference in melting point between the two polymers may be in one of the ranges of 30 ℃ or higher, about 30 ℃ to about 60 ℃, or about 30 ℃ to about 100 ℃.

The aforementioned propylene-based polymers can be prepared using a highly regioregular polymerization catalyst.

The highly regioregular polymerization catalyst may comprise a diester-based catalyst, a succinate-based catalyst, a metallocene catalyst, or a combination thereof.

The nonwoven fabric comprising composite fibers can be obtained by a general composite melt-spinning method without using a special apparatus. For example, the nonwoven fabric may be a spunbonded nonwoven fabric prepared by a spunbonding method exhibiting high productivity.

Hereinafter, a method of producing a spunbonded nonwoven fabric will be described in detail.

First, a first propylene-based polymer forming one region of a conjugate fiber and a second propylene-based polymer forming the other region of the conjugate fiber are respectively melted by two extruders or the like, and the melts are discharged from a nozzle having a conjugate spinning nozzle which is structured to form and discharge a desired fiber structure to discharge a conjugate long fiber.

Then, the discharged long fiber is cooled by cooling air, a tension is applied to the cooled long fiber by the air to allow the long fiber to have a predetermined fineness, and the stretched long fiber is directly collected in a collecting belt and deposited to a predetermined thickness.

Then, by using a needle punching, a water jet, an ultrasonic wave or the like; an embossing process using a heat embossing roller; or a hot melt method using hot ventilation air as the post-hybrid treatment.

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

Can be formed at an adhesion rate (i.e., embossed area ratio) of 13% or less and 0.2mm²Or greater (e.g., about 0.2 mm)²To about 0.7mm²) An embossing process is performed under a condition of a non-embossing unit area. Herein, the non-embossed unit area refers to a maximum area of a rectangle contacting an inside of an embossed portion in a minimum unit of the non-embossed portion surrounded on all sides thereof by the embossed portion. When the embossing treatment is performed under the condition of this range, a nonwoven fabric having a better bulkiness while maintaining the necessary strength can be obtained.

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

As a result of the embossing treatment, 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 in series at the same or different intervals.

Each of the plurality of unit embossing pattern portions has a shape of:

the fineness and basis weight of the nonwoven fabric may be appropriately selected depending on the purpose. Generally, the fineness of the nonwoven fabric can be from about 1.0 to about 2.5 denier, for example from about 0.7 to about 2.0 denier, and the basis weight of the nonwoven fabric can be about 15g/m²To about 100g/m²E.g. about 7g/m²To about 30g/m²。

Each of the embossing patterns included in each of the unit embossing pattern portions may have a thickness of about 0.2mm²To about 0.7mm²An area of the substrate.

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%, based on a total weight of the nonwoven fabric.

Fatty acid amides may be used as a slip agent.

The fatty acid amide may comprise oleamide, erucamide, stearic acid amide, or a combination thereof.

The composite fiber may contain other components as necessary in addition to the first propylene-based polymer and the second propylene-based polymer, as long as one of the objects of the present invention is not impaired. Examples of other components may include a heat stabilizer, a weathering stabilizer, various stabilizers, an antistatic agent, an anti-blocking agent, an anti-fogging agent, a filler, a dye, a pigment, natural oil, synthetic oil, wax, and combinations thereof.

The stabilizer may comprise an anti-aging agent such as 2, 6-di-tert-butyl-4-methylphenol (BHT); phenolic antioxidants such as tetrakis [ methylene-3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate ] methane, alkyl beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate or 2,2' -oxamide bis [ ethyl-3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate; fatty acid metal salts such as zinc stearate, calcium stearate, or calcium 1, 2-hydroxystearate; polyhydric alcohol fatty acid esters such as glycerol monostearate, glycerol distearate, pentaerythritol monostearate, pentaerythritol distearate or pentaerythritol tristearate; or a combination thereof.

The filler may comprise silica, diatomaceous earth, alumina, titania, magnesia, pumice powder, pumice spheres, 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.

The aforementioned propylene-based polymer and the aforementioned other components to be used as required can be mixed by a known method.

The composite fiber can be a single composite fiber, a core-sheath composite fiber, a side-by-side composite fiber or a sandwich composite fiber.

Hereinafter, a nonwoven fabric laminate according to an embodiment of the present invention will be described in detail.

The nonwoven fabric laminate according to an embodiment of the present invention may be a laminate having at least two layers. Here, at least one layer of the laminate may be the aforementioned nonwoven fabric.

The nonwoven fabric laminate may comprise a spunbonded nonwoven fabric of the aforementioned nonwoven fabrics.

Can be produced by laminating four spunbond sheetsWoven to form a nonwoven laminate. In this case, the nonwoven fabric laminate may have a uniformity (CV) of 3% or less. In the present specification, "uniformity (CV%)" refers to the process of cutting a nonwoven fabric laminate into 1m²The size of which is a percentage of a value obtained by dividing a weight deviation of 30 test samples by an average weight of 30 test samples after 30 test samples are produced.

A nonwoven fabric laminate formed by laminating four spunbonded nonwoven fabrics may have a thickness of 0.02mm or more, a curl number of 10EA/10mm or more, and an adhesion rate of 13% or less, and may have a Machine Direction (MD) stiffness of 40mm or less, which indicates the softness of the nonwoven fabric laminate. In this specification, "MD stiffness" refers to the flexural deformation of the nonwoven laminate in one machine direction (i.e., the degree of warp of the nonwoven laminate).

Hereinafter, an article according to an embodiment of the present invention will be described in detail.

An article according to an embodiment of the present invention comprises the aforementioned nonwoven fabric laminate.

The article may be a diaper, an absorbent article, a fecal article, a support layer, or a topsheet.

When the article is a diaper, the nonwoven fabric laminate has a hydrophilic agent impregnation amount (OPU: Oil Pick-UP) of 0.7% or less, and therefore when the nonwoven fabric laminate is applied to a topsheet layer of the diaper, the article can have a water absorption rate of 3 seconds or less.

The hydrophilic agent impregnation amount (OPU) can be calculated according to the following equation 1.

[ equation 1]

OPU(％)＝(W1-W0)/W0x100

In equation 1, W0 is a weight of the nonwoven laminate containing no hydrophilizing agent, and W1 is a weight of the nonwoven laminate containing the hydrophilizing agent. In the impregnation procedure, the hydrophilic agent is used in the form of an aqueous suspension of polydimethylsiloxane having a concentration of 15% by weight. However, in equation 1, the weight of the hydrophilic agent contained in the nonwoven fabric laminate refers to only the weight of the solid component.

Hereinafter, the present invention will be described in more detail by way of examples. The following examples are set forth to describe the present invention in more detail, and the scope of the present invention is not limited to these examples.

Examples 1 to 6 and comparative examples 1 to 5

Wherein a first propylene-based polymer (A) containing an erucamide slip and a second propylene-based polymer (B) containing an erucamide slip are subjected to conjugate melt spinning by a spunbond process to deposit side-by-side conjugate fibers having the structure of FIG. 2 on a collecting surface, and the conjugate fibers are subjected to embossing treatment by the embossing pattern shown in FIG. 1 by using a calender roll, the upper portion of which is heated to 146 ℃ and the lower portion of which is heated to 144 ℃, so as to produce a nonwoven fabric comprising crimped conjugate fibers. The type, physical properties and content ratio of the first propylene-based polymer (a) and the second propylene-based polymer (B), the amount of erucamide slip and the characteristics of the embossed pattern are given in table 1 below. In the table, MFR denotes a melt index measured under conditions of a temperature of 230 ℃ and a load of 2.16kg according to ASTM D1238, and slip agent denotes a weight relative to the total weight of the nonwoven fabric.

[ Table 1]

In table 1, PA1 to PA7 and PB are as follows.

(1) PA 1: 70 wt% of a propylene homopolymer (H7700, manufactured by LG chem.) and 30 wt% of an elastomeric random copolymer (T-7700, manufactured by LG chem.), in which ethylene is copolymerized with polypropylene

(2) PA 2: a mixture of 60% by weight of a propylene homopolymer (H7700, manufactured by LG chem.) and 40% by weight of an elastomeric random copolymer (VISTA MAX 7020, manufactured by EXXON), in which ethylene is copolymerized with polypropylene

(3) PA 3: a mixture of 40% by weight of a propylene homopolymer (H7700, manufactured by LG chem.) and 60% by weight of an elastomeric random copolymer (VERSIFY 4200, manufactured by DOW) in which ethylene is copolymerized with polypropylene

(4) PA 4: 70 wt% of a propylene homopolymer (H7700, manufactured by LG chem.) and 30 wt% of an elastomeric random copolymer (T-7700, manufactured by LG chem.), in which ethylene is copolymerized with polypropylene

(5) PA 5: 70 wt% of a propylene homopolymer (MH7700, manufactured by LG chem.) and 30 wt% of an elastomeric random copolymer (T-7700, manufactured by LG chem.), in which ethylene is copolymerized with polypropylene

(6) PA 6: a mixture of 60 wt% of a propylene homopolymer (MH7700, manufactured by LG chem.) and 40 wt% of an elastomeric random copolymer (T-7700, manufactured by LG chem.), in which ethylene is copolymerized with polypropylene

(7) PA 7: 70 wt% of a propylene homopolymer (H7700, manufactured by LG chem.) and 30 wt% of an elastomeric random copolymer (T-7700, manufactured by LG chem.), in which ethylene is copolymerized with polypropylene

(8) PB: propylene homopolymer (H562T, manufactured by PMC)

Evaluation example 1: evaluation of physical Properties of spunbonded nonwoven Fabric

The physical properties of the spunbonded nonwoven fabrics prepared in examples 1 to 6 and comparative examples 1 to 5 were evaluated as follows, and the results thereof are given in the following table 2.

(1) The weight per unit area (weight: g/m) was measured according to ASTM D3776-1985²)。

(2) Tensile strength: a maximum tensile load was obtained by performing a tensile test using a tensile strength measuring device (Instron) according to KSK 0520 under a test sample width of 5cm, an interval between test samples of 10cm and a tensile speed of 500 mm/min.

(3) Tensile elongation: when the nonwoven fabric was stretched to the maximum, the elongation was measured by the above method (2).

(4) Thickness (mm) was measured according to KSK 0506.

(5) Number of crimps: the number of filament curls in a 10mm range is directly measured using a microscope.

(6) Spinnability: the filament vibration was visually observed during melt spinning and polymer dripping was detected by a defect detector.

[ Table 2]

Referring to table 2, it was found that each of the nonwoven fabrics of crimped composite fibers prepared in examples 1 to 6 was thick, had a large amount of crimp, and had good or similar other physical properties such as tensile strength (MD: machine direction), tensile strength (CD: cross direction), tensile elongation (MD: machine direction), tensile elongation (CD: cross direction), and spinnability, as compared to each of the nonwoven fabrics prepared in comparative examples 1 to 5.

FIG. 3 is a partial view showing an embossing pattern of the nonwoven fabric of crimped conjugated fibers prepared in example 4.

Referring to FIG. 3, it was found that the nonwoven fabric of crimped conjugated fibers prepared in example 4 had a crimp number of about 20/10 mm.

Evaluation example 2: evaluation of physical Properties of nonwoven Fabric laminate comprising spunbonded nonwoven Fabric

The spunbonded nonwoven fabrics prepared in examples 1 to 6 and comparative examples 1 to 5 were laminated in four layers to produce nonwoven fabric laminates. Then, the physical properties of each of the nonwoven fabric laminates were evaluated by the following methods, and the results thereof are given in table 3 below.

(1) The uniformity (CV%) was measured by cutting the nonwoven fabric laminate into pieces of 1m²The size of the test specimen was evaluated as a percentage of a value obtained by dividing a weight deviation of one of the 30 test specimens by an average weight of the 30 test specimens after the 30 test specimens were produced. The smaller the uniformity (CV%) value, the better the uniformity.

(2) Thickness (mm) was measured according to KSK 0506.

(3) Number of crimps: the number of filament curls in a range of 10mm is directly measured using a microscope.

(4) The bonding rate (%) refers to a percentage in which heat is transferred to bond a portion of the nonwoven fabric as a relief portion of an embossed pattern.

(5) MD stiffness (mm): a bending distance when a nonwoven fabric laminate sample is brought into contact with an inclined surface is measured by a tester having an inclination of 45 deg. The smaller the MD stiffness, the better the flexibility.

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

(7) Water absorption rate: when artificial urine is dropped on the nonwoven fabric laminate according to EDANA 150.5(02), the time taken for the artificial urine to pass through the nonwoven fabric laminate is measured by a sensor.

[ Table 3]

Referring to table 3, it was found that each of the nonwoven laminates produced by laminating the four nonwoven fabrics of crimped composite fibers prepared in examples 1 to 6 had a good uniformity of 3% or less, was thick, had a large amount of crimping, had a small MD stiffness, had a similar OPU, and had a fast water absorption speed, as compared to each of the nonwoven laminates produced by laminating the four nonwoven fabrics of crimped composite fibers prepared in comparative examples 1 to 5.

It is to be understood that the embodiments described herein are to be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within various embodiments should generally be considered as available for other similar features or aspects in other embodiments.

Although one or more embodiments have been described with reference to the accompanying drawings, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims.

The claims (modification according to treaty clause 19)

1. A non-woven fabric of 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 second propylene-based polymer has a melting point higher than a melting point of the first propylene-based polymer by 30 ℃ or more as measured by a Differential Scanning Calorimeter (DSC), a ratio (second polymer/first polymer) of melt flow rates (MFR: measured temperature 230 ℃, load 2.16kg) of the first propylene-based polymer and the second propylene-based polymer is 1.7 or more, the melt flow rates are measured according to ASTM D1238, and a component ratio represented by a weight ratio of the first propylene-based polymer/the second propylene-based polymer is 50/50 to 10/90.

2. A non-woven fabric of crimped conjugated fibers according to 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 elastomeric random copolymer wherein ethylene is copolymerized with polypropylene, a propylene-ethylene-butylene terpolymer, or a combination thereof.

3. A non-woven fabric of crimped conjugated fibers according to claim 1,

wherein 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%, based on a total weight of the nonwoven fabric.

4. A non-woven fabric of crimped conjugated fibers according to claim 1,

wherein the non-woven fabric comprises an embossed portion and a non-embossed portion, and

the embossing part is an open embossing part and includes a plurality of unit embossing pattern parts which are consecutively arranged at the same or different intervals.

(deletion)

6. A non-woven fabric of crimped conjugated fibers according to claim 4,

wherein each of the embossing patterns included in the unit embossing pattern portions has about 0.2mm²To about 0.7mm²An area of the substrate.

7. A non-woven fabric of crimped conjugated fibers according to claim 4,

wherein the nonwoven fabric has an adhesion rate of 13% or less.

8. A non-woven fabric of crimped conjugated fibers according to claim 1,

wherein the crimped composite fiber is a single-type composite fiber, a core-sheath composite fiber, a side-by-side composite fiber, or a sandwich composite fiber.

9. A non-woven fabric of crimped conjugated fibers according to claim 1,

wherein the non-woven fabric is a spunbonded non-woven fabric.

10. A nonwoven fabric laminate having at least two layers,

wherein at least one layer of the laminate is a nonwoven fabric of crimped conjugated fibers according to any one of claims 1 to 4 and 6 to 9.

11. The nonwoven fabric laminate of claim 10,

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

12. The nonwoven fabric laminate of claim 11,

wherein the nonwoven fabric laminate has a thickness of 0.02mm or more, a curl number of 10EA/10mm or more, and an adhesion rate of 13% or less, and has a Machine Direction (MD) stiffness of 50mm or less in an adhesion region of an embossed pattern.

13. An article comprising the nonwoven fabric laminate of claim 10.

14. The article of claim 13, wherein said first layer is a multilayer,

wherein the article is a diaper, an absorbent article, a fecal article, a support layer, or a topsheet.

15. The article of claim 14, wherein said first layer is a multilayer,

wherein the nonwoven fabric laminate has a hydrophilic agent impregnation amount (OPU) of 0.7% or less when the article is a diaper, and thus the article has a water absorption rate of 3 seconds or less when the nonwoven fabric laminate is applied to a topsheet layer of the diaper.

Statement or declaration (modification according to treaty clause 19)

Claim 1 is modified; claims 2 to 4 are unchanged, claim 5 is deleted, claims 6 to 9 are unchanged, claims 10 and 13 are modified, claims 14 to 15 are unchanged.

i) The modification of claim 1 characterized by "the melting point of the first propylene-based polymer being 30 ℃ or more higher than the melting point of one of the second propylene-based polymers" to "the melting point of the second propylene-based polymer being 30 ℃ or more higher than the melting point of one of the first propylene-based polymers" which modification can be supported by table 2 of the original application;

ii) claim 10 is modified from "claims 1 to 9" to "claims 1 to 4 and 6 to 9", whereby the support of claim 10 of the original application document can be obtained;

iii) claim 13 is modified from "claims 10 to 12" to "claim 10", whereby the support of claim 13 of the original application can be obtained.

Claims

1. A non-woven fabric of 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 first propylene-based polymer has a melting point higher than a melting point of the second propylene-based polymer by 30 ℃ or more as measured by a Differential Scanning Calorimeter (DSC), a ratio (second polymer/first polymer) of melt flow rates (MFR: measured temperature 230 ℃, load 2.16kg) of the first propylene-based polymer and the second propylene-based polymer is 1.7 or more, the melt flow rates are measured according to ASTM D1238, and a component ratio represented by a weight ratio of the first propylene-based polymer/the second propylene-based polymer is 50/50 to 10/90.

2. A non-woven fabric of crimped conjugated fibers according to claim 1,

3. A non-woven fabric of crimped conjugated fibers according to claim 1,

4. A non-woven fabric of crimped conjugated fibers according to claim 1,

5. A non-woven fabric of crimped conjugated fibers according to claim 4,

wherein each of the plurality of unit embossing pattern portions has a shape of:

6. a non-woven fabric of crimped conjugated fibers according to claim 4,

7. A non-woven fabric of crimped conjugated fibers according to claim 4,

wherein the nonwoven fabric has an adhesion rate of 13% or less.

8. A non-woven fabric of crimped conjugated fibers according to claim 1,

9. A non-woven fabric of crimped conjugated fibers according to claim 1,

wherein the non-woven fabric is a spunbonded non-woven fabric.

10. A nonwoven fabric laminate having at least two layers,

wherein at least one layer of the laminate is a nonwoven fabric of crimped conjugated fibers according to any one of claims 1 to 9.

11. The nonwoven fabric laminate of claim 10,

12. The nonwoven fabric laminate of claim 11,

13. An article comprising the nonwoven fabric laminate of any one of claims 10 to 12.

14. The article of claim 13, wherein said first layer is a multilayer,

15. The article of claim 14, wherein said first layer is a multilayer,