JP6533025B1 - Method of manufacturing spunbonded nonwoven fabric and spunbonded nonwoven fabric - Google Patents

Abstract

A step of melt spinning a thermoplastic polymer to form crimped fibers, and a step of collecting the crimped fibers and pressing the collected crimped fibers with a compaction roll at a linear pressure of 5 N / mm or more And a method of producing a spunbonded nonwoven fabric.

Description

  The present disclosure relates to a method of manufacturing a spunbond nonwoven and a spunbond nonwoven.

  In recent years, non-woven fabrics are widely used in various applications because they are excellent in air permeability and flexibility. Therefore, while various characteristics according to the use are calculated | required by the nonwoven fabric, improvement of the characteristic is requested | required.

  In particular, long fiber non-woven fabrics obtained by the spunbond method are, for example, absorbent articles (paper diapers, sanitary napkins, etc.), medical materials (surgery wear gowns, drapes, sanitary masks, sheets, medical gauze, base materials) Applied to cloth etc.) In applications such as absorbent articles and medical materials, a high degree of flexibility is required, in particular, because they have parts that are in direct contact with the skin.

  For example, Patent Document 1 proposes a method for producing a spunbonded high loft nonwoven web comprising crimped multicomponent fibers having excellent flexibility.

Unexamined-Japanese-Patent No. 2018-24965

  In applications such as absorbent articles and medical materials, high flexibility and resistance to fuzzing, that is, excellent fuzz resistance are also required. In the manufacturing method described in Patent Document 1 described above, there is room for improvement in the resistance to fuzz.

  An object of the present disclosure is to provide a spunbonded nonwoven fabric excellent in fuzz resistance without losing flexibility and a method for producing the same.

  The present disclosure relates to the following aspects.

<1> A step of melt-spinning a thermoplastic polymer to form a crimped fiber, and collecting the crimped fiber and collecting the crimped fiber with a compaction roll at a linear pressure of 5 N / mm or more And a pressing step.
The temperature of the said compaction roll at the time of pressing the <2> crimped fiber is a manufacturing method of the spun bond nonwoven fabric as described in <1> which is 80 degreeC-120 degreeC.
The temperature of the said compaction roll at the time of pressing the said <3> crimped fiber is a manufacturing method of the spun bond nonwoven fabric as described in <1> lower than melting | fusing point of the said crimped fiber.
The manufacturing method of the spun bond nonwoven fabric as described in any one of <1>-<3> whose <4> said linear pressure is 10 N / mm or less.
The manufacturing method of the spun bond nonwoven fabric as described in any one of <1>-<4> in which the <5> above-mentioned thermoplastic polymer contains an olefin polymer.
<6> The method for producing a spunbonded nonwoven fabric according to <5>, wherein the olefin-based polymer contains a propylene-based polymer as an olefin-based polymer.
<7> On the non-woven web formed in the pressing step, crimped fibers formed by melt spinning a thermoplastic polymer are laminated, and the non-woven web obtained by laminating the crimped fibers is obtained Manufacture of a spunbonded nonwoven fabric according to any one of <1> to <6>, comprising the step of pressing with a compaction roll at a linear pressure of 5 N / mm or more, and producing a nonwoven fabric laminate comprising a plurality of spunbonded nonwoven fabric layers. Method.

When a friction test is performed on a 150 mm × 150 mm area of the <8> surface using a Gakushin-type friction fastness tester in accordance with the JIS L 0849 (2013) friction fastness test method, the following (1 A spunbonded nonwoven fabric satisfying at least one of (2) and (2).
(1) In the region, the number of hairballs having a circle equivalent diameter of 2.0 mm or more is zero, and the number of circle equivalent diameters of 0.8 mm or more and less than 2.0 mm is one or less.
(2) In the region, the number of hairballs having a circle equivalent diameter of 2.0 mm or more is 0, and the number of circle equivalent diameters of 0.1 mm or more and less than 0.8 mm is 9 or less.

  According to the present disclosure, a spunbonded nonwoven fabric excellent in fuzz resistance without losing flexibility and a method for producing the same are provided.

It is a schematic diagram showing an example of the device for manufacturing the nonwoven fabric layered product of this indication. It is a schematic diagram showing another example of the device for manufacturing the nonwoven fabric layered product of this indication.

  Hereinafter, an example of a preferred embodiment of the present disclosure will be described in detail. These descriptions and examples illustrate the embodiments and do not limit the scope of the embodiments.

The numerical range shown using "-" in this indication shows the range which includes the numerical value described before and after "-" as minimum value and the maximum value, respectively.
In the present disclosure, the term "step" is included in the term if the purpose of the step is achieved, even if it can not be clearly distinguished from other steps, not only an independent step.
In the present disclosure, the content of each component in the composition means the total amount of the plurality of types of substances unless a plurality of types of substances corresponding to each component are present.
In the present disclosure, the MD (Machine Direction) direction refers to the traveling direction of the nonwoven web in the nonwoven fabric manufacturing apparatus. The CD (Cross Direction) direction is a direction perpendicular to the MD direction and parallel to the main surface (surface orthogonal to the thickness direction of the nonwoven fabric).

<Method of manufacturing spunbond nonwoven fabric>
In the method of producing a spunbonded nonwoven fabric according to the present disclosure, a step of melt-spinning a thermoplastic polymer to form crimped fibers, and collecting the crimped fibers and collecting the crimped fibers with a compaction roll And a step of pressing at a linear pressure of 5 N / mm or more (hereinafter, also referred to as “step (1) of pressing crimped fibers”).

  The manufacturing method of this indication manufactures the spun bond nonwoven fabric which is excellent in fuzz resistance, without spoiling flexibility by including the process of pressing the crimped fiber which was collected with a compaction roll and linear pressure 5N / mm or more. can do.

[Step of forming crimped fiber]
The manufacturing method of the present disclosure includes the step of melt spinning a thermoplastic polymer to form crimped fibers. The step of forming a crimped fiber is not particularly limited as long as a crimped fiber can be formed, and a known process of cooling and drawing a thermoplastic polymer may be included.
The thermoplastic polymer used by the manufacturing method of this indication is as below-mentioned.

[Step (1) of pressing crimped fibers]
The manufacturing method of the present disclosure includes the steps of collecting crimped fibers and pressing the collected crimped fibers with a compaction roll at a linear pressure of 5 N / mm or more.

  The temperature of the compaction roll when pressing the crimped fiber may be 80 ° C. to 120 ° C., may be 85 ° C. to 115 ° C., may be 90 ° C. to 110 ° C., 95 ° C. to It may be 105 ° C.

  The temperature of the compaction roll when pressing crimped fibers is preferably lower than the melting point of the crimped fibers.

  The linear pressure when pressing the crimped fibers is preferably 5.1 N / mm or more, and more preferably 5.2 N / mm or more from the viewpoint of fuzz resistance.

  The linear pressure when pressing the crimped fiber is preferably 10 N / mm or less, more preferably 7.0 N / mm or less, and 6.5 N / mm or less from the viewpoint of flexibility. Is more preferable, and particularly preferably 6.0 N / mm or less.

  The nonwoven fabric laminate of the present disclosure may have a crimped portion and a non-crimped portion from the viewpoint of excellent flexibility. The area ratio of the crimped portion is preferably 7% to 20%. The area ratio of the crimped portion is more preferably 8% or more and 18% or less. The area ratio of the crimped part was obtained by collecting a test piece of 10 mm × 10 mm in size from the nonwoven fabric laminate and observing the contact surface of the test piece with the embossing roll with an electron microscope (magnification: 100 times) The ratio of the area of the thermocompression-bonded part

(Thermoplastic polymer)
The thermoplastic polymer is not particularly limited as long as it can constitute a spunbonded nonwoven fabric. Examples of the thermoplastic polymer include olefin polymers, polyester polymers, polyamide polymers, polymer compositions of these polymers, and the like. The olefin polymer is a polymer containing an olefin as a structural unit. The polyester-based polymer is a polymer containing an ester as a structural unit, and the polyamide-based polymer is a polymer containing an amide as a structural unit. In the present disclosure, the thermoplastic polymer is a concept including a thermoplastic polymer composition.

  Among these, the thermoplastic polymer preferably contains an olefin-based polymer, and more preferably contains a propylene-based polymer as the olefin-based polymer.

  The propylene-based polymer is, for example, a homopolymer of propylene, and a propylene / α-olefin random copolymer (for example, a random copolymer of propylene and one or more α-olefins having 2 to 8 carbon atoms). Polymers are preferred. Propylene and ethylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 4-methyl-1-pentene etc. are mentioned as a specific example of a preferable alpha-olefin from a viewpoint which is excellent in flexibility. The content of α-olefin in the propylene / α-olefin random copolymer is not particularly limited, and is preferably, for example, 1 mol% to 10 mol%, and more preferably 1 mol% to 5 mol%. .

  The melting point (Tm) of the propylene-based polymer may be 125 ° C. or higher, and may be 125 ° C. to 165 ° C. The melt flow rate (MFR) (ASTM D-1238, 230 ° C., load 2160 g) may be 10 g / 10 minutes to 100 g / 10 minutes, or 20 g / 10 minutes to 70 g / 10 minutes.

  The crimped fiber used in the manufacturing method of the present disclosure may be a fiber containing one type of thermoplastic polymer, or may be a composite fiber containing two or more types of thermoplastic polymers. In addition, the composite fiber may be, for example, a side-by-side type, a concentric core-sheath type, or an eccentric core-sheath type. The eccentric core-sheath type composite fiber may be an exposed type in which the core portion is exposed on the surface, or a non-exposed type in which the core portion is not exposed on the surface.

  Among these, the crimped fiber is preferably a crimped conjugate fiber containing a propylene-based polymer, and more preferably an eccentric core-sheath crimped conjugate fiber containing a propylene-based polymer.

  In the same way, in the crimped conjugate fiber, the propylene-based polymer is contained on the side having many exposed portions on the surface of the crimped conjugate fiber, and the propylene-based polymer is a propylene / α-olefin copolymer, or More preferably, it is a mixture of a propylene homopolymer and a propylene / α-olefin copolymer. The side with many exposed portions on the surface represents the side where the thermoplastic polymer is more exposed in the crimped composite fiber. In the present disclosure, the side having many exposed portions on the surface is collectively referred to as a sheath. Moreover, the side with few parts exposed to the surface is generically called a core part.

  When the crimped composite fiber is a core-sheath type, a preferable embodiment of the mass ratio (core / sheath) between the sheath and the core is, for example, 90/10 to 60/40 (more preferably 85/15). To 40/60).

  The crimped fibers may, if necessary, contain commonly used additives. The additives include, for example, antioxidants, weather stabilizers, light stabilizers, dispersants, antistatic agents, antifogging agents, antiblocking agents, lubricants, nucleating agents, pigments, penetrants, wetting agents and the like. .

  The spun bond nonwoven fabric obtained by the production method of the present disclosure preferably has a tensile load in the MD direction of the spun bond nonwoven fabric of 10 N / 25 mm to 30 N / 25 mm, and more preferably 15 N / 25 mm to 25 N / 25 mm. .

  The spun bond non-woven fabric obtained by the production method of the present disclosure preferably has a tensile load in the CD direction of the spun bond non-woven fabric of 5 N / 25 mm to 20 N / 25 mm, more preferably 10 N / 25 mm to 15 N / 25 mm. .

  The spun bond non-woven fabric obtained by the production method of the present disclosure preferably has a tensile strength of at least 2.0 N / 25 mm at 5% stretch in the MD direction of the spun bond non-woven fabric, and is 3.0 N / 25 mm or more Is more preferred.

  The spun bond non-woven fabric obtained by the production method of the present disclosure preferably has a tensile strength of 0.5 N / 25 mm or more at the time of 5% stretching of the spun bond non-woven fabric in the CD direction, and is 0.8 N / 25 mm or more. Is more preferred.

  The tensile load and the tensile strength at 5% elongation of the spunbond nonwoven fabric may be measured in accordance with JIS L 1913 (2010). Specifically, a test piece of width 25 mm × length 200 mm is taken from a spunbond nonwoven fabric, MD is measured at a distance between chucks of 100 mm and a head speed of 100 mm / min using a tensile tester, and the average value is 5 To calculate the tensile load (N / 25 mm). Further, in the measurement program, the strength recorded at the time of 5% stretching (between chucks: 105 mm) may be taken as the load at 5% stretching (5% load).

Basis weight of the spunbonded nonwoven fabric obtained by the manufacturing method of the present disclosure is not particularly limited, for example, basis weight of the spunbonded nonwoven fabric ^may be ^{5g / m 2 ~30g / m 2} , 20g / m 2 ~30g may be / ^{m 2,} may be ^{25g / m 2 ~30g / m 2} .

  Tensile load in the MD direction of the spunbond nonwoven fabric, tensile load in the CD direction of the spunbond nonwoven fabric, tensile strength at 5% stretching in the MD direction of the spunbond nonwoven fabric, tensile strength at 5% stretch in the CD direction of the spunbond nonwoven fabric, The fabric weight of the spunbonded nonwoven fabric can be determined by the method described in the examples.

  The average fiber diameter of the crimped fibers is not particularly limited, and may be, for example, 5 μm to 25 μm. The average fiber diameter may be 20 μm or less, 18 μm or less, or 15 μm or less. The average fiber diameter may be 7 μm or more, or 10 μm or more. In the present disclosure, the average fiber diameter is determined as follows. Ten points of 10 mm × 10 mm test pieces are collected from the obtained spunbonded non-woven fabric, and the diameter of the fiber is read in μm units to the first decimal place at a magnification of 20 using a Nikon ECLIPSE E400 microscope. Measure the diameter at any 20 points for each test piece and determine the average value.

  The spunbonded nonwoven fabric obtained by the manufacturing method of the present disclosure may be a single layer nonwoven fabric or a multilayer nonwoven fabric (nonwoven fabric laminate) in which a plurality of layers are laminated. The non-woven fabric laminate may be, for example, a laminate in which two or more spunbonded non-woven fabric layers are laminated.

[Step of pressing crimped fiber (2)]
According to the manufacturing method of the present disclosure, crimped fibers formed by melt-spinning a thermoplastic polymer are laminated on the nonwoven web formed in the step (1) of pressing crimped fibers, You may include the process of pressing the said nonwoven web on which the fiber was laminated | stacked by 5 N / mm or more of line pressure with a compaction roll. Thereby, the nonwoven fabric layered product provided with two layers of a spun bond nonwoven fabric layer can be manufactured. The preferable conditions in the step (2) of pressing the crimped fibers are the same as the preferable conditions in the step (1) of pressing the crimped fibers, and thus the description thereof is omitted.

  In addition, you may manufacture the nonwoven fabric laminated body provided with three or more layers of spun bond nonwoven fabric layers by repeating the process (2) which presses crimped fiber.

[Process of entanglement of non-woven web]
The manufacturing method of the present disclosure may include, after the step (1) of pressing the crimped fibers, a step of heat and pressure treatment of the nonwoven web to entangle. When the spunbonded nonwoven fabric obtained by the manufacturing method of the present disclosure is a nonwoven fabric laminate, after the step (2) of pressing the crimped fibers, the step of heating and pressing the nonwoven web to entangle is included. It is also good.

  Here, with reference to FIG. 1, the manufacturing method of the nonwoven fabric laminated body of this indication is demonstrated. FIG. 1 is a schematic view showing an example of an apparatus for producing the nonwoven fabric laminate of the present disclosure. The nonwoven fabric manufacturing apparatus 100 shown in FIG. 1 includes a first spinning unit 11A and a second spinning unit 11B. The first spinning unit 11A and the second spinning unit 11B have the same components. The same components as in the first spinning unit 11A and the second spinning unit 11B will be assigned the same reference numerals and descriptions thereof will be omitted.

  The non-woven fabric production apparatus 100 includes a first extruder 31A for extruding a thermoplastic polymer, a second extruder 31B for extruding a plastic polymer, a spinneret 33 for melt-spinning a molten thermoplastic polymer, and a spinneret 33. Ejector 37 for stretching continuous fiber group 20 (20A, 20B) melt spun from 33, moving collection member 51 for collecting extended continuous fiber group 20, moving continuous fiber group 20 Suction unit 39 for efficient collection on the top, compaction rolls 41 and 42 for pressing the continuous fiber group 20, embossing roll 53 and flat roll 55 for thermocompression bonding, and nonwoven laminate 60 after thermocompression bonding And the winder 71 which winds up. The compaction rolls 41 and 42 are rollers for unifying the light fibers and performing pretreatment for enabling the fibers to withstand the post-process (for example, thermocompression bonding by the embossing roll 53).

  In the first spinning unit 11A, first, the thermoplastic polymer is melt-spun from the spinneret 33 to form the continuous fiber group 20A. By extruding the first thermoplastic polymer from the first extruder 31A and extruding the second thermoplastic polymer from the second extruder 31B and performing composite spinning, it is a continuous fiber group 20A that is crimped fibers. Is obtained. Next, the continuous fiber group 20A is cooled by the cooling air 35 and drawn by the ejector 37. The drawn continuous fiber group 20A is efficiently collected on the movable collection member 51 by a suction unit 39 provided at the lower part of the collection surface of the movable collection member 51. The collected continuous fiber group 20A is pressed with a linear pressure of 5 N / mm or more by the compaction roll 41 on the upper side and the compaction roll 42 on the lower side to form the first nonwoven web 40A. .

  The continuous fiber group 20B is similarly formed in the second spinning unit 11B. The continuous fiber group 20B is laminated on the first nonwoven web 40A. The first nonwoven web 40A in which the continuous fiber group 20B is laminated is pressed by the compaction rolls 41 and 42 at a linear pressure of 5 N / mm or more, to form a second nonwoven web 40B, and a laminated structure is formed. Nonwoven webs are formed. The first nonwoven web 40A is an underlying nonwoven web layer and the second nonwoven web 40B is an upper nonwoven web layer. The nonwoven web of laminated structure is thermocompression-bonded by the embossing roll 53, and the nonwoven fabric laminated body 60 provided with two layers of spun bond nonwoven fabric layers is obtained. Thereafter, the non-woven fabric laminate 60 is wound by the winder 71.

  Moreover, in the manufacturing method of the nonwoven fabric laminated body of this indication, you may use the manufacturing apparatus provided with the spinning part 12 whose cooling chamber shown in FIG. 2 is a closed type structure. FIG. 2 is a schematic view showing another example of an apparatus for producing the nonwoven fabric laminate of the present disclosure. FIG. 2 shows an apparatus in which the spinning unit 11 (the spinning unit 11A and the spinning unit 11B) in the nonwoven fabric manufacturing apparatus 100 shown in FIG. That is, the apparatus configuration other than the spinning unit 11 is the same as the manufacturing apparatus shown in FIG. The same components as those of the manufacturing apparatus shown in FIG. The compaction rolls 41 and 42 are omitted in FIG.

  The spinning unit 12 includes a first extruder 32A for extruding a first thermoplastic polymer, a second extruder 32B for extruding a second thermoplastic polymer, and a melted first thermoplastic polymer and A spinneret 34 for melt spinning the second thermoplastic polymer, a cooling chamber 38C for cooling the continuous fiber group 22 melt-spun from the spinneret 34, and cooling air supply portions 38A and 38B for supplying the cooling air 36 And an extending portion 38D for extending the continuous fiber group 22.

  In the spinning unit 12, the first thermoplastic polymer and the second thermoplastic polymer are extruded and introduced into the spinneret 34. Next, the melted first and second thermoplastic polymers are melt spun from the spinneret 34. The melt spun continuous fiber group 22 is introduced into the cooling chamber 38C. The continuous fiber group 22 is cooled by the cooling air 36 supplied from one or both of the cooling air supply unit 38A and the cooling air supply unit 38B. The cooled continuous fiber group 22 is introduced into the extending portion 38D provided on the downstream side of the cooling chamber 38C. The extending portion 38D is provided in a bottleneck shape. The continuous fiber group 22 introduced to the drawing section 38D is drawn by increasing the speed of the cooling air in the bottleneck. The drawn continuous fiber group 22 is dispersed and collected on the movable collection member 51. Then, the continuous fiber group 22 dispersed is efficiently collected on the movable collection member 51 by the suction unit 39 provided at the lower part of the collection surface of the movable collection member 51, and the nonwoven web 43 is It is formed.

<Spunbond nonwoven fabric>
When the spun bond nonwoven fabric of the present disclosure is subjected to a friction test on a 150 mm × 150 mm area of the surface using a Gakushin-type friction fastness tester in accordance with the JIS L 0849 (2013) friction fastness test method. And at least one of the following (1) and (2):
(1) In the region, the number of hairballs having a circle equivalent diameter of 2.0 mm or more is zero, and the number of circle equivalent diameters of 0.8 mm or more and less than 2.0 mm is one or less.
(2) In the region, the number of hairballs having a circle equivalent diameter of 2.0 mm or more is 0, and the number of circle equivalent diameters of 0.1 mm or more and less than 0.8 mm is 9 or less.
The spunbonded nonwoven fabric of the present disclosure is excellent in fuzz resistance without losing flexibility. The spunbonded nonwoven fabric of the present disclosure can be produced, for example, by the above-described production method of the present disclosure. The preferable conditions of the spunbonded nonwoven fabric of the present disclosure are the same as those of the spunbonded nonwoven fabric obtained by the production method of the present disclosure described above, and thus the description thereof is omitted. The method of the friction test will be described in detail in the following examples.

<Laminate>
The spunbonded nonwoven fabric of the present disclosure may be a laminate comprising the spunbonded nonwoven fabric of the present disclosure. That is, the laminate may have a structure in which the spunbonded nonwoven fabric of the present disclosure and a layer other than the spunbonded nonwoven fabric of the present disclosure are laminated. The other layer may be one layer or two or more layers.

  Other layers include fiber aggregates such as knitted fabrics, woven fabrics, and nonwoven fabrics (short fiber nonwoven fabrics, long fiber nonwoven fabrics) other than the spunbonded nonwoven fabrics of the present disclosure. Non-woven fabrics other than the spun-bonded non-woven fabric of the present disclosure include various known non-woven fabrics (spun-bonded non-woven fabric, melt-blown non-woven fabric, wet non-woven fabric, dry non-woven fabric, dry pulp non-woven fabric, flash spun non-woven fabric, open non-woven fabric, etc.). The fiber assembly may be a sheet of natural fibers such as cotton. Moreover, resin films, such as polyolefin, polyester, a polyamide, etc. are mentioned as another layer. These may be combined and stacked. For example, the spunbonded nonwoven fabric of the present disclosure, a resin film, and a fiber assembly of natural fibers such as cotton may be laminated in this order.

As a film to be laminated with the spunbonded nonwoven fabric of the present disclosure, a breathable film or a moisture-permeable film is preferable when the laminate needs to have breathability.
Breathable films include various known breathable films. For example, films of thermoplastic elastomers such as polyurethane elastomers having moisture permeability, polyester elastomers, and polyamide elastomers, and porous films formed by stretching and porosifying a thermoplastic resin film containing inorganic particles or organic particles can be mentioned. . Examples of the thermoplastic resin used for the porous film include polyolefins such as high pressure low density polyethylene, linear low density polyethylene (so-called LLDPE), high density polyethylene, polypropylene, polypropylene random copolymer, and a combination thereof.
When the laminate does not require air permeability, one or more non-porous thermoplastic resin films selected from polyolefins (polyethylene, polypropylene, etc.), polyesters, and polyamides may be used.

  The method for further laminating (bonding) other layers to the spunbonded nonwoven fabric of the present disclosure is not particularly limited, and mechanical embossing such as thermal embossing, thermal fusion such as ultrasonic fusion, needle punch, water jet, etc. There are various methods such as a method, a method using an adhesive such as a hot melt adhesive and a urethane adhesive, and an extrusion laminate.

  Hereinafter, the present invention will be more specifically described based on examples, but the present invention is not limited to these examples. In the following examples, “%” represents mass%.

  Physical property values and the like in Examples and Comparative Examples were measured by the following methods.

(1) Weight per unit area (g / m ² )
Ten points of a test piece of 100 mm (flow direction: MD) × 100 mm (direction orthogonal to the flow direction: CD) were collected from the obtained nonwoven fabric laminate. The test pieces were collected at 10 points in the CD direction. Subsequently, the mass [g] of each of the collected test pieces was measured using an electronic balance (manufactured by Kensei Kogyo Co., Ltd.). The average value of the mass of each test piece was determined. The average value determined was converted to a mass (g) per 1 m ² , and the second decimal place was rounded off to obtain a basis weight (g / m ² ) of each nonwoven fabric laminate sample.
The results are shown in Table 1.

(2) Thickness [mm]
From the obtained nonwoven fabric laminate, 10 points of a 100 mm (MD) × 100 mm (CD) test piece were collected. The collecting point of the test piece was the same as the test piece for measuring the coating weight. Subsequently, thickness [mm] was measured with the method as described in JIS L 1096: 2010 using load type thickness gage (made by Ozaki Mfg. Co., Ltd.) with respect to each collected test piece. The average value of the thickness of each test piece was determined, and the second decimal place was rounded off to obtain the thickness [mm] of each nonwoven fabric laminate sample.
The results are shown in Table 1.

(4) Bending resistance (cantilever method)
The cantilever test was implemented by the following method, and the bending resistance [mm] of the nonwoven fabric laminate was measured.
Specifically, in accordance with JIS-L 1096: 2010, 8.19.1 [Method A (45 ° cantilever method)], the bending resistance is measured for each of the MD direction and the CD direction, and the average value is measured. It was set as the bending resistance of the nonwoven fabric laminate.
The results are shown in Table 2.

(5) Evaluation of Fuzz Two points of 150 mm (MD) × 150 mm (CD) CD test pieces were collected from the non-woven fabric. In addition, collection place was made into two arbitrary places. Then, using the Gakushin type friction fastness tester (manufactured by Daiei Kagaku Seiki Mfg., New model NR-100), each of the collected test pieces was subjected to a friction test in accordance with the JIS L 0849 rub fastness test method. The A cloth tape (made by Teraoka Mfg. Co., Ltd., No. 1532) is attached to the friction element side, and with a load of 300 g applied, the non-embossed surface is reciprocated 100 times in the MD direction and rubbed. The fuzzing state of the friction surface was rated according to the following criteria, and the worse grade was regarded as fuzzing of each non-woven fabric sample (evaluation point).
The results are shown in Table 2.
The evaluation criteria for fuzzing are as follows. In addition, if it is evaluation point 3 or more (third grade or more), it is excellent in fuzz resistance.
-Evaluation of fuzz-
Grade 1: The fibers are peeled off and the holes are open enough to damage the test piece.
2nd grade: If the test piece is a laminate, the surface layer peels off and becomes thin enough to see the back layer, or if it is a single layer body, fibers are peeled off remarkably.
Grade 2.5: A pill (diameter: 2 mm or more) is clearly seen clearly, and fibers begin to rise at multiple locations.
3rd grade: Clear pill (diameter: 0.8 mm or more) begins to appear, or a plurality of small pill (diameter: less than 0.8 mm) is seen.
Grade 3.5: It is fluffed to such an extent that small hairballs (diameter: 0.1 mm or more and less than 0.8 mm) can begin to form in one place.
Fourth grade: no fuzz

Example 1
Composite melt spinning was performed by a spun bond method on a thermoplastic polymer as a core component described below and a thermoplastic polymer as a sheath component described below. Then, an eccentric core-sheath crimped composite fiber having a mass ratio of the core component / the sheath component of 15/85 was deposited on the moving collection surface. The crimped conjugate fiber was pressed at a linear pressure of 5.5 N / mm using a compaction roller at 100 ° C. to form a first spunbonded nonwoven web (first layer). Next, a first spunbonded nonwoven web is formed by depositing eccentric core / core crimped composite fibers obtained on the first spunbonded nonwoven web under the same conditions as described above and depositing the crimped composite fibers. Were pressed at a linear pressure of 5.5 N / mm using a compaction roll at 100 ° C. to form a second spunbonded nonwoven web (second layer). The two-layered laminated structure is thermocompression-bonded at 150 ° C. so that the flat roll contacts the first spunbonded nonwoven web side and the embossing roll contacts the second spunbonded nonwoven web side, and the nonwoven laminate (Spunbond nonwoven layer / spunbond nonwoven layer) was obtained. The total basis weight of the nonwoven fabric laminate was 27.0 g / m ² , and the area ratio of the crimped portion was 12.9%.

-Core component-
MFR: 60 g / 10 min, melting point 162 ° C., propylene homopolymer-sheath component-
Propylene-ethylene random copolymer with MFR 60 g / 10 min, melting point 142 ° C., ethylene content 4% by mass

Example 2
A linear pressure of 5.5 N / mm when pressing a crimped composite fiber, a first spunbonded nonwoven web having the crimped composite fiber deposited, and a laminated structure having the crimped composite fiber deposited using a compaction roll The nonwoven fabric laminate was obtained in the same manner as in Example 1 except that it was changed to 5.8 N / mm. The total basis weight of the nonwoven fabric laminate was 27.0 g / m ² , and the area ratio of the crimped portion was 12.9%.

Comparative Example 1
A linear pressure of 5.5 N / mm when pressing a crimped composite fiber, a first spunbonded nonwoven web having the crimped composite fiber deposited, and a laminated structure having the crimped composite fiber deposited using a compaction roll A nonwoven fabric laminate was obtained in the same manner as in Example 1 except that it was changed to 4.8 N / mm. The total basis weight of the nonwoven fabric laminate was 27.0 g / m ² , and the area ratio of the crimped portion was 12.9%.

  From the above results, the nonwoven fabric laminates obtained in Examples 1 and 2 were better in evaluation of fuzzing than the nonwoven fabric laminate obtained in Comparative Example 1, and were excellent in fuzz resistance. In addition, the nonwoven fabric laminate obtained in Example 1, 2 has the same degree of flexibility as the nonwoven fabric laminate obtained in Comparative Example 1, and in Examples 1, 2 It was possible to suppress fuzzing without damaging it.

  All documents, patent applications, and technical standards described herein are as specifically and individually indicated that the individual documents, patent applications, and technical standards are incorporated by reference. Incorporated herein by reference.

Claims (4)

Melt spinning a propylene-based polymer to form crimped fibers;
Collecting the crimped fibers and pressing the collected crimped fibers with a compaction roll at a linear pressure of 5 N / mm or more and 7 N / mm or less ;
A method of producing a spunbonded nonwoven fabric comprising:   The method for producing a spunbonded nonwoven fabric according to claim 1, wherein the temperature of the compaction roll when pressing the crimped fiber is 80 ° C to 120 ° C.   The method for producing a spunbonded nonwoven fabric according to claim 1, wherein the temperature of the compaction roll when pressing the crimped fiber is lower than the melting point of the crimped fiber. A crimped fiber formed by melt-spinning a propylene-based polymer is laminated on the nonwoven web formed in the pressing step, and the nonwoven web on which the crimped fiber is laminated is formed by a compaction roll. The nonwoven fabric according to any one of claims 1 to 3 , comprising the step of pressing at a linear pressure of 5 N / mm or more and 7 N / mm or less , and producing a nonwoven fabric laminate having a plurality of spunbond nonwoven fabric layers. Production method.