JP2020139244A - Laminated nonwoven fabric - Google Patents

Abstract

To provide a laminated nonwoven fabric capable of suppressing liquid back, while having excellent liquid permeability.SOLUTION: A laminated nonwoven fabric comprises a heat-fusible nonwoven fabric layer (A) and an ultra fine fiber nonwoven fabric layer (B) laminated to each other. As a fiber (Fa) constituted of the heat-fusible nonwoven fabric layer (A), at least a composite fiber (Fa1) including at least a first thermoplastic resin composition (Pa11) and a second thermoplastic resin composition (Pa12) is used. A fiber (Fb) constituted of the ultra fine fiber nonwoven fabric layer (B) is made of fiber of polyester resin made by copolymerization with polyethylene glycol in the range of 5 mass% or more and 40 mass% or less, the fiber having an average single fiber diameter of 0.1 μm or more and 5.0 μm or less. The percentage of the heat-fusible nonwoven fabric layer (A) in the thickness direction is 70% or more and 98% or less.SELECTED DRAWING: Figure 1

Description

The present invention relates to a laminated non-woven fabric having excellent liquid permeability and liquid return prevention property.

Absorbent articles such as disposable diapers generally include a liquid-permeable front sheet, a liquid-impermeable back sheet, and a liquid-retaining absorber interspersed between the two sheets. The absorber is generally composed of a liquid-retaining absorbent core coated with a liquid-permeable packaging sheet. The absorbent core is generally formed by spraying a highly absorbent polymer onto a fiber aggregate such as pulp fiber.

In such an absorbent article, there is a demand for high absorbency and a thin, compact and non-bulky thickness of the absorbent article itself. Therefore, it has been proposed to reduce the thickness of the absorber. (For example, Patent Document 1).

The absorber is generally composed of a fibrous base material typified by pulp fibers and a superabsorbent polymer, and the excrement is absorbed by first stocking the fibrous base material and then using a superabsorbent polymer. It is designed to be fixed.

On the other hand, since the packaging sheet is intended to maintain the shape of the absorber and prevent leakage of highly absorbent polymer particles, it is necessary to have a dense fiber structure in which the absorber material does not come out. Since it is a wrapping material, it is required to have excellent liquid permeability. Crepe paper is widely used as a material for packaging sheets, and various improvements have been conventionally proposed in order to meet such high demands (see, for example, Patent Documents 2 to 4).

Japanese Unexamined Patent Publication No. 10-118117 Japanese Unexamined Patent Publication No. 2009-148322 Japanese Unexamined Patent Publication No. 2001-314444 Japanese Unexamined Patent Publication No. 2012-148060

As a means for thinning the absorber, it is conceivable to reduce the amount of the bulky fibrous base material used. However, this not only reduces the stock capacity of excrement fluid, but also tends to cause a phenomenon called gel blocking, in which the superabsorbent polymer gels and the property of absorbing the liquid of the absorber (liquid absorption) is significantly reduced. There is a problem that the entire absorber cannot be used uniformly even with a small amount of excrement, and a phenomenon called "liquid return" occurs in which urine once absorbed by the absorber returns to the surface of the article. Further, if the packaging sheet is made of a dense non-woven fabric in order to suppress liquid return, the liquid permeability is inferior, and conversely, if the packaging sheet is made of a coarse non-woven fabric, there is a problem that the fibrous base material comes out. Was difficult. Therefore, an object of the present invention is to provide a laminated non-woven fabric which is excellent in liquid permeability while suppressing liquid return.

As a result of diligent studies to achieve the above object, the present inventors have made polyethylene terephthalate obtained by copolymerizing polyethylene glycol, which is a hydrophilic polymer, at a specific ratio into an ultrafine fibrous non-woven fabric, and heat composed of short fibers. It has been found that by using a non-woven fabric in which a fusible non-woven fabric is laminated, for example, when it is used as a packaging sheet for paper diapers, it is possible to suppress liquid return and improve liquid permeability. The present invention has been completed based on this finding, and according to the present invention, the following inventions are provided.

The laminated non-woven fabric of the present invention is a laminated non-woven fabric in which a heat-bondable non-woven fabric layer (A) and an ultrafine fiber non-woven fabric layer (B) are laminated, and is a fiber constituting the heat-bondable non-woven fabric layer (A). As (Fa), at least a composite fiber (Fa1) composed of at least the first thermoplastic resin composition (Pa11) and the second thermoplastic resin composition (Pa12) is used, and the ultrafine fibrous nonwoven fabric layer (B) is used. The fibers (Fb) constituting the above are composed of fibers made of a polyester-based resin, and the polyester-based resin is copolymerized with polyethylene glycol in a range of 5% by mass or more and 40% by mass or less, and the average single fiber diameter thereof. Is 0.1 μm or more and 5.0 μm or less, and the proportion of the heat-sealing nonwoven fabric layer (A) in the thickness direction is 70% or more and 98% or less.

According to a preferred embodiment of the laminated nonwoven fabric of the present invention, the average single fiber diameter of the composite fiber (Fa1) is 7.0 μm or more and 24.0 μm or less.

According to a preferred embodiment of the laminated nonwoven fabric of the present invention, the fibers (Fa) constituting the heat-sealing nonwoven fabric layer (A) are, in addition to the composite fibers (Fa1), one or more kinds of fibers (Fa2). It is a laminated non-woven fabric containing.

According to a preferred embodiment of the laminated nonwoven fabric of the present invention, the laminated nonwoven fabric in which the melting point of the first thermoplastic resin composition (Pa11) is 10 degrees or more higher than the melting point of the second thermoplastic resin composition (Pa12). is there.

According to the present invention, a laminated non-woven fabric that suppresses liquid return and has excellent liquid permeability can be obtained. In particular, the laminated non-woven fabric of the present invention is suitably used for members such as packaging sheets for disposable diapers because of the above-mentioned characteristics.

FIG. 1 is a conceptual cross-sectional view illustrating the laminated nonwoven fabric according to the present invention.

The laminated non-woven fabric of the present invention is a laminated non-woven fabric in which a heat-bondable non-woven fabric layer (A) and an ultrafine fiber non-woven fabric layer (B) are laminated, and is a fiber constituting the heat-bondable non-woven fabric layer (A). As (Fa), at least a composite fiber (Fa1) composed of at least the first thermoplastic resin composition (Pa11) and the second thermoplastic resin composition (Pa12) is used, and the ultrafine fibrous nonwoven fabric layer (B) is used. The fibers (Fb) constituting the above are composed of fibers made of a polyester-based resin, and the polyester-based resin is copolymerized with polyethylene glycol in a range of 5% by mass or more and 40% by mass or less, and the average single fiber diameter thereof. Is 0.1 μm or more and 5.0 μm or less, and the proportion of the heat-sealing nonwoven fabric layer (A) in the thickness direction is 70% or more and 98% or less. The components thereof will be described in detail below, but the present invention is not limited to the scope described below as long as the gist thereof is not exceeded.

[Heat-fused non-woven fabric layer (A) and its components]
The heat-bondable nonwoven fabric layer (A) of the present invention comprises at least a first thermoplastic resin composition (Pa11) and a second thermoplastic resin composition (Pa12) as fibers (Fa) constituting the layer (A). At least a composite fiber (Fa1) is used. More preferably, it further contains one or more kinds of fibers (Fa2). Each will be described in detail below.

(The first thermoplastic resin composition (Pa11) and the second thermoplastic resin composition (Pa12))
First, at least the composite fiber (Fa1) used as the fiber (Fa) is composed of at least the first thermoplastic resin composition (Pa11) and the second thermoplastic resin composition (Pa12). In particular, the melting points of the first thermoplastic resin composition (Pa11) and the melting points of the second thermoplastic resin composition (Pa12) were compared from the viewpoint of thermal adhesion to the ultrafine fibrous nonwoven fabric layer (B). In some cases, it is preferable that the melting point of the first thermoplastic resin (Pa11) is higher. Further, it is more preferable that the melting point of the first thermoplastic resin composition (Pa11) is 10 ° C. or more higher than the melting point of the second thermoplastic resin composition (Pa12). However, the melting point of the first thermoplastic resin composition (Pa11) is 10 higher than the melting point of the second thermoplastic resin composition (Pa12) from the viewpoint of handleability when made into a non-woven fabric and processability into a sanitary material. It is preferably high in the range of ° C. or higher and 150 ° C. or lower.

Examples of the first thermoplastic resin composition (Pa11) include polyester, polyamide and polyolefin. Specific examples of the polyester include polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate and the like. Specific examples of the polyamide include polyamide 6, polyamide 66, and polyamide 12. Examples of polyolefins include polyethylene, polypropylene and propylene / ethylene copolymers. Among them, polyamide 6, polybutylene terephthalate and polypropylene are preferably used from the viewpoint of flexibility, and polyethylene terephthalate is preferably used from the viewpoint of cost.

Further, the first thermoplastic resin composition (Pa11) may be copolymerized with other components, and may contain additives such as particles, a flame retardant and an antistatic agent.

Examples of the copolymerization component include sodium 5-sulfoisophthalate and 3-hydroxybutanoic acid. Examples of the particles include titanium oxide. Further, examples of the flame retardant include an organic flame retardant and an inorganic flame retardant. Further, as the antistatic agent, for example, an alcohol-based antistatic agent can be mentioned.

As the second thermoplastic resin composition (Pa12), polyethylene or polypropylene can be used, and polyethylene is particularly preferably used from the viewpoint of adhesiveness. Polyethylene is classified according to the difference in manufacturing method and physical properties, and includes high-density polyethylene (HDPE), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and the like, each of which is being studied for fibers. Although any polyethylene is used in the present invention, it is preferable to use LLDPE from the viewpoint of spinning stability.

It is permissible that the polyethylene used as the second thermoplastic resin composition (Pa12) is also blended with a small amount of the other component polymer and / or copolymerized. Examples of the other component polymer include polyolefin-based polymers such as polypropylene and poly (4-methyl-1-pentene) having a melting point close to that of polyethylene, as well as low-melting polyester and low-melting polyamide. Further, in order to fully express the characteristics of polyethylene, the mass ratio of the blend is preferably 5% by mass or less, more preferably 2% by mass or less. Further, in the copolymer, the copolymerization amount of the copolymerization component contained in the second thermoplastic resin composition is preferably 50% by mass or less.

The melt flow rate of this polyethylene (hereinafter, may be referred to as MFR) is preferably 10 to 100 g / 10 minutes, more preferably 20 to 40 g / 10 minutes. The melt flow rate referred to here refers to a value measured at a temperature of 190 ° C. and a load of 2.16 kg in accordance with ASTM D1238 (Method A).

Further, in the first thermoplastic resin composition (Pa11) and the second thermoplastic resin composition (Pa12) used in the present invention, antioxidants usually used as long as the effects of the present invention are not impaired. Additives such as agents, weather stabilizers, light stabilizers, antistatic agents, antifoaming agents, antiblocking agents, lubricants such as polyethylene wax, nucleating agents, and pigments, or other polymers as needed. be able to.

(Fibers (Fa) constituting the heat-bondable non-woven fabric layer (A))
The fiber (Fa) constituting the heat-bondable nonwoven fabric layer (A) is a composite fiber (Pa12) composed of at least a first thermoplastic resin composition (Pa11) and a second thermoplastic resin composition (Pa12). Fa1) is at least used.

The mass ratio (Pa11 / Pa12) of (Pa11) and (Pa12) of the composite fiber (Fa1) of the present invention is preferably 90/10 to 10/90, and is 70/30 to 30/70. Is more preferable, and 60/40 to 40/60 is a more preferable embodiment. By setting the mass ratio of the first thermoplastic resin composition (Pa11) to preferably 10% by mass or more, more preferably 30% by mass or more, still more preferably 40% by mass or more, sufficient physical properties are imparted to the nonwoven fabric. can do. Further, by setting the mass ratio of the second thermoplastic resin composition (Pa12) to preferably 10% by mass or more, more preferably 30% by mass or more, still more preferably 40% by mass or more, sufficient thermal adhesiveness is obtained. Is obtained.

In the cross-sectional shape of the composite fiber (Fa1) of the present invention, it is preferable that the low melting point component forms at least a part of the fiber surface. Examples of the cross-sectional shape may be a concentric core-sheath structure, an eccentric core-sheath structure, and a side-by-side structure.

The average single fiber diameter of the composite fiber (Fa1) of the present invention is preferably 7.0 μm or more and 24.0 μm or less. By setting the average single fiber diameter to preferably 8.0 μm or more, more preferably 10.0 μm or more, and further preferably 12.0 μm or more, the spinnability when the polymer is stretched into fibers in the manufacturing process is improved. Since it is stable and the number of adhesion points between fibers when made into a non-woven fabric increases, the strength can be increased. Further, by setting the average single fiber diameter to preferably 22.0 μm or less, more preferably 20.0 μm or less, and further preferably 18.0 μm or less, the flexibility required for use in sanitary materials is good. Can be.

As the average single fiber diameter of the composite fiber (Fa1) according to the present invention, a value obtained by the following method is adopted.
(1) Collect 30 measurement samples of vertical × horizontal = 1 cm × 1 cm from an arbitrary place on the non-woven fabric.
(2) Adjust the magnification to 200 to 3000 times with a scanning electron microscope, and take a total of 30 photographs of the fiber surface from the collected samples.
(3) Measure all the single fiber diameters for which the single fiber diameter can be clearly confirmed in the photograph, and round off the second decimal place of their arithmetic mean value (μm) to obtain the average single. The fiber diameter.

Further, as the fibers (Fa) constituting the heat-sealing nonwoven fabric layer (A), those containing one or more kinds of fibers (Fa2) in addition to the composite fibers (Fa1) are more preferable. For example, by making the fiber (Fa2) a composite fiber larger than the average single fiber diameter of the composite fiber (Fa1), the heat-sealing nonwoven fabric layer (A) can be made bulkier. Therefore, it is possible to obtain a laminated non-woven fabric having excellent flexibility such that it deforms and recovers according to the elongation of the body. On the other hand, for example, by making the fiber (Fa2) a composite fiber smaller than the average single fiber diameter of the composite fiber (Fa1), it can be applied to sanitary materials such as disposable diapers, and is delicate, soft, and compatible with the skin. It can be a laminated non-woven fabric having a good feel.

The fibers (Fa2) are not limited to composite fibers, for example, natural fibers such as cotton, silk and wool, biscous rayon, cupra, and solvent-spun cellulose fibers (eg, "Riocel"®. ) And "Tencel" (registered trademark)), polyolefin fibers, polyester fibers and polyamide fibers, (poly) acrylic single fibers composed of acrylic nitrile, polycarbonate, polyacetal, polystyrene, cyclic polyolefin, etc. It may be a fiber made of engineering plastic or the like.

(Heat-fused non-woven fabric layer (A))
The heat-sealing nonwoven fabric layer (A) according to the laminated nonwoven fabric of the present invention is composed of the fibers (Fa).

The thickness of the heat-sealing nonwoven fabric layer (A) of the present invention is preferably 0.30 mm or more and 1.60 mm or less. When the thickness is 0.40 mm or more, more preferably 0.50 mm or more, the bulkiness can be maintained and the liquid return can be suppressed. On the other hand, by setting the thickness to 1.60 mm or less, more preferably 1.50 mm or less, the laminated non-woven fabric can be made more flexible and feel better to the touch.

In the present invention, the thickness (mm) of the heat-sealing nonwoven fabric layer (A) is a value obtained by the following method.
(1) Collect 10 measurement samples of vertical × horizontal = 1 cm × 1 cm from an arbitrary place of the laminated non-woven fabric.
(2) Adjust the magnification to 20 to 80 times with a scanning electron microscope, and take cross-sectional photographs of a total of 30 laminated non-woven fabrics at 3 locations at random from the collected sample.
(3) Measure the thickness of each non-woven fabric layer in each photograph, and round off the third decimal place of their arithmetic mean value (mm).

The basis weight of the heat-sealing nonwoven fabric layer (A) of the present invention is preferably 5 g / m ² or more and 80 g / m ² or less. When the basis weight is 5 g / m ² or more, more preferably 10 g / m ² or more, and further preferably 15 g / m ² or more, an appropriate thickness can be maintained and liquid return can be suppressed. On the other hand, flexibility can be imparted by setting the content to 80 g / m ² or less, more preferably 70 g / m ² or less, still more preferably 60 g / m ² or less.

In the present invention, the basis weight (g / m ² ) of the heat-sealing nonwoven fabric layer (A) is a value obtained by the measurement method described later.

[Ultrafine fiber non-woven fabric layer (B) and its components]
In the ultrafine fibrous nonwoven fabric layer (B) of the present invention, the fibers (Fb) constituting the ultrafine fibrous non-woven fabric layer (B) are made of fibers made of a polyester resin. Further, in the polyester resin, polyethylene glycol is copolymerized in a range of 5% by mass or more and 40% by mass or less. Further, the average single fiber diameter of the fiber (Fb) is 0.1 μm or more and 5.0 μm or less. Each will be described in detail below.

(Polyester resin)
Examples of the polyester-based resin used for the fiber (Fb) constituting the ultrafine fiber non-woven fabric layer (B) of the present invention include polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polylactic acid, etc., and in particular, polyethylene terephthalate. Is a preferred embodiment. By using polyethylene terephthalate, the fiber has excellent flexibility and tactile sensation, and can be drawn at a high spinning speed, so that the fiber can easily undergo orientation crystallization and have mechanical strength.

Further, it is important that the polyester resin used in the present invention is copolymerized with polyethylene glycol. Since the polyester resin is copolymerized with polyethylene glycol, it is possible to suppress the elution of hydrophilic components during liquid passage.

The copolymerization amount of polyethylene glycol contained in the polyester resin used in the present invention is characterized in that it is 5% by mass or more and 40% by mass or less. By setting the copolymerization amount of polyethylene glycol to 5% by mass or more, more preferably 7% by mass or more, a non-woven fabric having excellent flexibility and tactile sensation can be obtained. Further, by setting the copolymerization amount of polyethylene glycol to 40% by mass or less, more preferably 20% by mass or less, it is possible to obtain a fiber having heat resistance and high mechanical strength that can withstand practical use. The copolymerization amount of polyethylene glycol contained in the copolymerized polyester resin in the present invention refers to a value measured and calculated by the following method.
(1) Collect about 0.05 g of a copolymerized polyester resin.
(2) Add 1 mL of 28% aqueous ammonia to this and heat at 120 ° C. for 5 hours to dissolve the sample.
(3) After allowing to cool, 1 mL of purified water and 1.5 mL of 6 mol / L hydrochloric acid are added, and the volume is adjusted to 5 mL with purified water.
(4) Centrifuge and filter through a filter with a mesh pore size of 0.45 μm.
(5) The molecular weight distribution of the filtrate is measured by GPC.
(6) The number average molecular weight of polyethylene glycol is calculated using a calibration curve of molecular weight prepared using a standard sample having a known molecular weight.
(7) Further, the polyethylene glycol is quantified using the calibration line of the solution concentration prepared with the polyethylene glycol aqueous solution, and the copolymerization amount of the polyethylene glycol in the copolymer polymer is calculated.

The number average molecular weight of the polyethylene glycol contained in the polyester resin used in the present invention is preferably 4000 or more and 20000 or less. By setting the number average molecular weight of polyethylene glycol to 4000 or more, more preferably 5000 or more, hygroscopicity can be imparted to the polyester resin, and a non-woven fabric having a good tactile sensation can be obtained. Further, by setting the number average molecular weight of polyethylene glycol to 20,000 or less, more preferably 10,000 or less, a spunbonded non-woven fabric having excellent yarn-forming properties when made into a polyester resin can be obtained. The number average molecular weight of the polyethylene glycol contained in the copolymerized polyester resin in the present invention refers to a value measured and calculated by the following method.
(1) Collect about 0.05 g of polyester resin.
(2) Add 1 mL of 28% aqueous ammonia to this and heat at 120 ° C. for 5 hours to dissolve the sample.
(3) After allowing to cool, 1 mL of purified water and 1.5 mL of 6 mol / L hydrochloric acid are added, and the volume is adjusted to 5 mL with purified water.
(4) Centrifuge and filter through a filter with a mesh pore size of 0.45 μm.
(5) The molecular weight distribution of the filtrate is measured by GPC.
(6) The number average molecular weight of polyethylene glycol is calculated using a calibration curve of molecular weight prepared using a standard sample having a known molecular weight.

To the polyester-based resin used in the present invention, pigments for coloring, antioxidants, lubricants such as polyethylene wax, heat-resistant stabilizers and the like can be added as long as the effects of the present invention are not impaired.

The melting point of the polyester resin used in the present invention is preferably 200 ° C. or higher and 300 ° C. or lower, more preferably 220 ° C. or higher and 280 ° C. or lower. By setting the melting point to preferably 200 ° C. or higher, more preferably 220 ° C. or higher, it becomes easy to obtain heat resistance that can withstand practical use. Further, by setting the melting point to preferably 300 ° C. or lower, more preferably 280 ° C. or lower, it becomes easier to cool the threads discharged from the mouthpiece, fusion of fibers is suppressed, and the obtained non-woven fabric has few defects. It becomes a thing. The melting point of the polyester resin in the present invention refers to a value obtained from the peak top temperature of the endothermic peak obtained by measuring with a differential scanning calorimeter under nitrogen and at a heating rate of 16 ° C./min. ..

The polyester production method of the present invention is produced by a known polymerization method such as a transesterification method or an esterification method. In the transesterification method, an ester-forming derivative of terephthalic acid and ethylene glycol are charged in a reaction vessel and reacted in a range of 150 ° C. or higher and 250 ° C. or lower in the presence of a transesterification catalyst, and then a stabilizer, a polycondensation catalyst, etc. are added. It can be obtained by heating in the range of 250 ° C. or higher and 300 ° C. or lower under a reduced pressure of 500 Pa or lower and reacting for 3 hours or more and 5 hours or less. In the esterification method, terephthalic acid and ethylene glycol are charged in a reaction vessel and an esterification reaction is carried out at 150 ° C. or higher and 270 ° C. or lower under nitrogen pressure. After the esterification reaction is completed, a stabilizer, a polycondensation catalyst, etc. are added to 500 Pa or less. It can be obtained by heating under a reduced pressure of 250 ° C. or higher and 300 ° C. or lower and reacting for 3 hours or more and 5 hours or less.

In the method for producing a polyester of the present invention, the timing of adding polyethylene glycol is not particularly limited, and it may be added together with other raw materials before the esterification reaction or transesterification reaction, or after the esterification reaction or transesterification reaction is completed. , It may be added before the start of the transesterification reaction.

In the method for producing a polyester of the present invention, examples of the transesterification catalyst include zinc acetate, manganese acetate, magnesium acetate and titanium tetrabutoxide, and examples of the catalyst for polycondensation include antimony trioxide, germanium dioxide and titanium tetrabutoxide. Be done.

(Fibers (Fb) constituting the ultrafine non-woven fabric layer (B))
The fiber (Fb) constituting the ultrafine fibrous nonwoven fabric layer (B) of the present invention is made of the polyester resin described above.

The average single fiber diameter of the fiber (Fb) is 0.1 μm or more and 5.0 μm or less. By setting the average single fiber diameter to 0.1 μm or more, preferably 0.4 μm or more, more preferably 0.7 μm or more, and further preferably 0.9 μm or more, the polymer is stretched and thinned in the manufacturing process. At that time, it is possible to prevent the fibers from being cut and shots (polymer lumps) to be generated to make the texture rough, and it is possible to secure sufficient liquid permeability. Further, by setting the average single fiber diameter to 5.0 μm or less, preferably 4.0 μm or less, more preferably 3.0 μm or less, the texture of the ultrafine fiber non-woven fabric is made uniform, and the ultrafine fiber non-woven fabric is made dense. For example, powder dropping can be suppressed to a degree sufficient for use as a packaging sheet.

As the average single fiber diameter of the fiber (Fb) according to the present invention, a value obtained by the following method is adopted.
(1) Collect 30 measurement samples of vertical × horizontal = 1 cm × 1 cm from an arbitrary place on the non-woven fabric.
(2) Adjust the magnification to 200 to 3000 times with a scanning electron microscope, and take a total of 30 photographs of the fiber surface from the collected samples.
(3) Measure all the single fiber diameters for which the single fiber diameter can be clearly confirmed in the photograph, and round off the second decimal place of their arithmetic mean value (μm) to obtain the average single. The fiber diameter.

The ultrafine fibrous nonwoven fabric layer (B) of the present invention is composed of the above-mentioned fibers (Fb).

Further, the thickness of the ultrafine fibrous nonwoven fabric layer (B) of the present invention is preferably 0.03 mm or more and 1.00 mm or less. By setting the thickness to 0.03 mm or more, more preferably 0.05 mm, still more preferably 0.10 mm or more, the strength required for processing can be obtained. On the other hand, by setting the thickness to 1.00 mm or less, more preferably 0.80 mm or less, still more preferably 0.70 mm or less, it is possible to obtain a high degree of flexibility and a good touch.

In the present invention, the thickness (mm) of the ultrafine fibrous nonwoven fabric layer (B) is a value obtained by the following method.
(1) Collect 10 measurement samples of vertical × horizontal = 1 cm × 1 cm from an arbitrary place of the laminated non-woven fabric.
(2) Adjust the magnification to 20 to 80 times with a scanning electron microscope, and take cross-sectional photographs of a total of 30 laminated non-woven fabrics at 3 locations at random from the collected sample.
(3) Measure the thickness of each non-woven fabric layer in each photograph, and round off the third decimal place of their arithmetic mean value (mm).

The basis weight of the ultrafine fibrous nonwoven fabric layer (B) of the present invention is preferably 5 g / m ² or more and 20 g / m ² or less. By having a basis weight of 5 g / m ² or more, more preferably 8 g / m ² or more, still more preferably 10 g / m ² or more, for example, the powder drop is suppressed to a sufficient extent for use as a packaging sheet. Can be done. On the other hand, sufficient liquid permeability can be obtained by setting the content to 20 g / m ² or less, more preferably 18 g / m ² or less, and further preferably 15 g / m ² or less.

In the present invention, the basis weight (g / m ² ) of the ultrafine fibrous nonwoven fabric layer (B) is a value obtained by the measurement method described later.

[Laminated non-woven fabric]
It is necessary that the ratio of the heat-bondable nonwoven fabric layer (A) of the laminated nonwoven fabric of the present invention in the thickness direction is 70% or more and 98% or less. By setting the ratio in the thickness direction to 70% or more, more preferably 75%, still more preferably 80% or more, liquid return is suppressed. On the other hand, by setting the ratio in the thickness direction to 98% or less, more preferably 96%, still more preferably 95% or less, the powder falling prevention property can be satisfied.

The ratio of the heat-sealing nonwoven fabric layer (A) in the thickness direction and the proportion of the ultrafine fibrous nonwoven fabric layer (B) in the thickness direction shall be the values obtained by the following methods. To do.
(1) Collect 10 measurement samples of vertical × horizontal = 1 cm × 1 cm from an arbitrary place on the non-woven fabric.
(2) Adjust the magnification to 20 to 80 times with a scanning electron microscope, and take cross-sectional photographs of a total of 30 laminated non-woven fabrics at 3 locations at random from the collected sample.
(3) Measure the thickness of each non-woven fabric layer in each photograph, and round off the third decimal place of their arithmetic mean value (mm).
(4) calculating the ratio between the thickness D _A and layered nonwoven fabric overall thickness D of the heat fusible non-woven fabric layer (A).
Ratio in the thickness direction of the-heat fusible non-woven fabric layer _{(A) = (D A /} D) × 100 (%)
(5) The ratio of the thickness D _{B of the} ultrafine fibrous nonwoven fabric layer (B) to the thickness D of the entire laminated nonwoven fabric is calculated.
- percentage of the thickness direction of the microfibrous non-woven fabric layer _{(B) = (D B /} D) × 100 (%)
Further, the basis weight of the laminated nonwoven fabric of the present invention is preferably 10 g / m ² or more and 100 g / m ² or less. When the basis weight is 10 g / m ² or more, more preferably 15 g / m ² or more, and further preferably 20 g / m ² or more, sufficient strength and powder drop prevention property can be obtained. On the other hand, by setting the content to 100 g / m ² or less, more preferably 80 g / m ² or less, still more preferably 60 g / m ² or less, sufficient liquid permeability can be obtained as a packaging sheet. As the basis weight according to the present invention, a value obtained by the following method shall be adopted.
(1) The mass of a 15 cm square non-woven fabric piece obtained from an arbitrary place on the non-woven fabric is measured at three points.
(2) The measured value is converted into a value per 1 m ^{2, and} the value obtained by rounding off the arithmetic mean value (g / m ² ) to the first decimal place is used as the basis weight.

Further, the textures of the heat-bondable non-woven fabric layer (A) and the ultrafine fiber non-woven fabric layer (B) are the same as the texture (g / m ² ) of the laminated non-woven fabric, and the heat-bondable non-woven fabric layer (A). The value (g / m ² ) is rounded to the first digit after the decimal point by multiplying the ratio in the thickness direction of the above or the ratio in the thickness direction of the ultrafine fibrous nonwoven fabric layer (B). ..

Further, the laminated non-woven fabric of the present invention can be used as a laminated non-woven fabric by laminating other non-woven fabrics. For example, a sheet having a higher rigidity than the ultrafine fiber non-woven fabric of the present invention can be laminated to increase the mechanical strength and used, or it can be used in combination with a non-woven fabric having high chemical resistance and heat resistance. The method for laminating the laminated non-woven fabric of the present invention and another non-woven fabric may be any method that does not impair the effects of the present invention, a method of bonding the non-woven fabrics to each other using an adhesive, and a moisture-curable urethane resin spray method. The method of spraying with, the method of spraying thermoplastic resin or heat-sealing fiber, placing it on a running conveyor and pasting it through a heating furnace, or laminating it on a non-woven fabric manufactured by a manufacturing method other than the melt blow method by the melt blow method. The method etc. can be mentioned. Among them, the spray method using a moisture-curable urethane resin is a more preferable method because it is possible to bond two non-woven fabrics without pressing, so that an increase in pressure loss at the time of bonding can be reduced. is there.

[Manufacturing method of laminated non-woven fabric]
Next, an example of the method for producing the laminated nonwoven fabric of the present invention will be described.

The laminated non-woven fabric of the present invention is produced by forming a heat-bondable non-woven fabric layer (A) and an ultrafine fiber non-woven fabric layer (B) and laminating them.

(Formation of heat-sealing non-woven fabric layer (A))
As a method for forming the heat-bondable nonwoven fabric layer (A) in the present invention, a method for forming a long-fiber nonwoven fabric layer containing composite fibers composed of two or more components of a thermoplastic resin by a spunbond method or a melt blow method, or a short method It is possible to employ a method (air-through method) in which the fibers are formed into a fiber web by a card and then treated with hot air to form an air-through non-woven fabric layer. Above all, the air-through method can be preferably applied because a material having good bulkiness can be obtained.

The air-through method is a manufacturing method in which short fibers, which are raw cotton, are passed through a card machine to open the short fibers, formed into a fiber web state, and then heat-treated to form a non-woven fabric.

Regarding the heat treatment method, for example, heat bonding by hot air treatment, fusion by ultrasonic waves, heat embossed rolls in which a pair of upper and lower roll surfaces are engraved (concavo-convex parts), and one roll surface is flat (smooth). ) Thermal embossing roll consisting of a combination of a roll with engraving (unevenness) on the surface of the other roll, and thermocompression bonding with various rolls such as a thermal calendar roll consisting of a combination of upper and lower flat (smooth) rolls. , And each combination can be applied.

Of these, thermal adhesion by hot air treatment is particularly preferably used because it can maintain the thickness of the non-woven fabric, that is, the bulkiness.

[Formation of ultrafine fiber non-woven fabric layer (B)]
Next, a method for producing the ultrafine fibrous nonwoven fabric layer of the present invention will be described.

Examples of the ultrafine fibrous nonwoven fabric of the present invention include a melt blow method, a spunbond method and an electrospinning method, but the melt blow method is preferable in that fine fibers and thick fibers can be produced without requiring a complicated process. Used. In the melt blow method, the raw material is melted in an extruder and supplied to the mouthpiece, and hot air is blown to the yarn extruded from the mouthpiece to make the yarn finer, and then a non-woven fiber web is formed on the collection net. According to this melt blow method, fibers having a fine fineness can be obtained without a complicated process, so that a dense and uniform ultrafine fibrous nonwoven fabric can be obtained.

In the present invention, the polyester resin is melted in an extruder, weighed and supplied to a spinneret, and spun as long fibers. The spinning temperature when the polyester resin is melted and spun is preferably in the range of 250 ° C. or higher and 340 ° C. or lower. When the temperature is 250 ° C. or higher, more preferably 260 ° C. or higher, and even more preferably 280 ° C. or higher, the molten state of the polyester resin becomes uniform and the spinnability is excellent. On the other hand, by setting the temperature to 340 ° C. or lower, more preferably 330 ° C. or lower, still more preferably 320 ° C. or lower, thermal denaturation of the polyester resin in the spinning machine can be suppressed.

Further, in the present invention, the temperature of the hot air when the hot air is blown onto the yarn extruded from the mouthpiece is preferably equal to or higher than the above-mentioned spinning temperature (spinning temperature + 60 ° C.). By setting the spinning temperature or higher, more preferably (spinning temperature + 10 ° C.) or higher, and even more preferably (spinning temperature + 20 ° C.) or higher, the thread shape spun from the spinneret can be efficiently thinned. On the other hand, a stable spinning state can be maintained by setting the temperature to (spinning temperature + 60 ° C.) or less, more preferably (spinning temperature + 50 ° C.) or less, and even more preferably (spinning temperature + 40 ° C.) or less.

(Lamination of non-woven fabric layer)
The method for producing the laminated non-woven fabric of the present invention can be any method as long as it can be in a state where the heat-sealing non-woven fabric layer (A) and the ultrafine fiber non-woven fabric layer (B) are laminated. It can be carried out. For example, a method in which a fiber web formed of short fibers by a card machine is directly deposited on an ultrafine fiber non-woven fabric and fused by heat treatment to form a heat-sealing non-woven fabric, or an ultrafine fiber non-woven fabric and a spunbonded non-woven fabric are used. A method of fusing the laminated non-woven fabric layer and the heat-bondable non-woven fabric layer formed by forming a fiber web formed of short fibers by a card machine into a non-woven fabric by heat treatment is adopted. be able to.

(Heat adhesion of non-woven fabric layer)
In the manufacturing process of the laminated nonwoven fabric of the present invention, the step of heat-bonding the nonwoven fabric layers to each other can also be preferably adopted.

In the case of heat bonding by hot air treatment, the hot air temperature is preferably in the range of the melting point of the lowest melting point component of the resins used in all the non-woven fabric layers to be bonded, which is +1 ° C or more and + 30 ° C or less. It is preferably in the range of + 1 ° C. or higher and + 15 ° C. or lower, and more preferably in the range of + 1 ° C. or higher and + 10 ° C. or lower. Sufficient thermal adhesion can be obtained by setting the hot air temperature to the melting point of the low melting point component + 1 ° C. or higher. Further, by setting the hot air temperature to preferably the melting point of the low melting point resin at + 30 ° C. or lower, more preferably + 15 ° C. or lower, and further preferably 10 ° C. or lower, curing of the non-woven fabric due to heat can be suppressed, and paper diapers and the like can be suppressed. As a non-woven fabric for sanitary materials, it can maintain a flexible texture.

Further, in the present invention, the amount of hot air is preferably 1.0 m / sec or more and 5.0 m / sec or less. By setting the amount of hot air to 1.0 m / sec or more, the non-woven fabric for sanitary materials can be ventilated with hot air, and sufficient adhesiveness can be obtained. On the other hand, by setting the hot air volume to 5.0 m / sec or less, web turbulence during heat treatment can be suppressed.

(Heat treatment process)
For the purpose of improving the adhesiveness between the nonwoven fabric layers or obtaining a laminated nonwoven fabric having a predetermined thickness, a heat treatment step such as heat and pressure treatment, that is, embossing or calendar processing can also be preferably adopted.

The embossed adhesive area ratio in the embossing is preferably 5% or more and 30% or less. By setting the bonding area to preferably 5% or more, more preferably 10% or more, strength that can be put into practical use can be obtained. On the other hand, by setting the embossed adhesive area ratio to preferably 30% or less, and more preferably 20% or less, a flexible texture can be maintained.

The embossed adhesive area ratio referred to here is the portion of the non-woven fabric in which the convex portion of the upper roll and the convex portion of the lower roll overlap and come into contact with the fiber web when heat-bonding is performed by a roll having a pair of irregularities. It refers to the ratio. Further, in the case of heat treatment using a roll having irregularities and a flat roll, it means the ratio of the convex portion of the roll having irregularities to the entire non-woven fabric of the portion in contact with the fiber web.

As the shape of the engraving applied to the thermal embossing roll, a shape such as a circle, an ellipse, a square, a rectangle, a parallelogram, a rhombus, a regular hexagon, and a regular octagon can be used.

The surface temperature of the heat embossed roll is preferably −50 ° C. or higher and -1 ° C. or lower with respect to the melting point of the resin having the lowest melting point among the resins used in all the non-woven fabric layers. The surface temperature of the heat embossed roll is preferably -50 ° C or higher, more preferably -30 ° C or higher, and further preferably -10 ° C or higher with respect to the melting point of the resin having the lowest melting point. It can be heat-bonded to give strength and make it easier to suppress the occurrence of fluff. On the other hand, among the resins used, the melting point of the resin having the lowest melting point is preferably -1 ° C. or lower so that it is easy to prevent the resins from peeling off due to melting of the fibers. it can.

On the other hand, the temperature of the calendar roll during the heat treatment by the calendar processing is preferably -1 ° C. or lower with respect to the melting point of the resin which is the lowest melting point component. By setting the calendar roll temperature to -1 ° C. or lower with respect to the melting point of the low melting point component, it is possible to prevent the surface of the non-woven fabric from being cured after the heat treatment. The calendar roll temperature can be appropriately adjusted according to the thickness of the target non-woven fabric.

Further, the linear pressure of the roll during heat treatment by calendar or embossing is preferably 10 N / cm or more and 500 N / cm or less. By setting the linear pressure to preferably 10 N / cm or more, more preferably 15 N / cm or more, and further preferably 20 N / cm or more, sufficient heat treatment can be performed and the thickness can be controlled. On the other hand, by setting the linear pressure to preferably 500 N / cm or less, more preferably 400 N / cm or less, and further preferably 300 N / cm or less, the texture of the non-woven fabric is maintained by not applying too much stress to the roll. can do. The linear pressure of the roll can be appropriately adjusted depending on the thickness of the target non-woven fabric.

As the surface material of the heat embossed roll, a metal roll and a metal roll are used in order to obtain a sufficient thermocompression bonding effect and prevent the engraving (uneven part) of one embossed roll from being transferred to the surface of the other roll. A pair is a preferred embodiment.

Since the laminated nonwoven fabric of the present invention can improve hydrophilicity and suppress liquid return, it can be suitably used as, for example, a packaging sheet for disposable diapers, but its application range is limited to this. is not.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the following Examples are not of a nature limiting the present invention, and any design modification according to the gist described in the present specification is a technique of the present invention. It is included in the target range. In addition, in the measurement of each physical property, if there is no particular description, the measurement is performed based on the above method.

[Measuring method]
(1) Melting Point of Polyester Resin The melting point of the polyester resin was measured using a differential scanning calorimeter (“DSCQ2000” manufactured by TA Instruments) according to the above method.

(2) Measurement of Number Average Molecular Weight and Copolymerization Amount of Polyethylene Glycol Contained in Copolymerized Polyester Resin In the measurement of the number average molecular weight and copolymerization amount of polyethylene glycol, the GPC measuring device and measurement conditions are as follows. And said.
-Device: Gel permeation chromatograph GPC
-Detector: Differential refractive index detector RI (Tosoh "RI-8020", sensitivity 128x)
・ Photodiode array detector ("SPD-M20A" manufactured by Shimadzu Corporation)
-Column: TSKgelG3000PWXL (1) (Tosoh)
-Solvent: 0.1 M sodium chloride aqueous solution-Flow velocity: 0.8 mL / min
-Column temperature: 40 ° C
・ Injection volume: 0.05 mL
-Standard sample: polyethylene glycol, polyethylene oxide (3) Metsuke of laminated non-woven fabric (g / m ² )
The basis weight of the laminated non-woven fabric was calculated by the above method using an electronic balance "JP-300P (manufactured by CHYO)".

(4) Average single fiber diameter (μm) and ratio in the thickness direction of the non-woven fabric layer The average single fiber diameter and the ratio in the thickness direction of the non-woven fabric layer are the scanning electron microscope "VHX-D500 (manufactured by KEYENCE)". Was calculated by the above method.

(5) Liquid permeability The liquid permeability is evaluated using a LISTER strike-through tester manufactured by LENZING. The evaluation procedure is as follows.
(A) A sample cut to a size of 125 x 125 mm is placed on three sheets of filter paper (filter paper "ERT-FF3 Hollingworth &Vose") having a size of 100 x 100 mm, and energization transmission is performed on the sample. Place the liquid plate.
(B) Set the filter paper, sample and current-carrying liquid permeable plate in the main body of the strike-through tester.
(C) Put 5 mL of physiological saline into the main body of the strike-through tester.
(D) From the main body of the strike-through tester, the physiological saline solution (room temperature) is dropped into the opening of the energized liquid permeable plate.
(E) Record the energizing time of the energizing liquid permeable plate.
(F) (C) to (E) are repeated three times.
(G) The measurement is carried out three times, and the average value thereof is taken as the liquid permeation time.

When the sample was not set, that is, the liquid permeation time for three filter papers was 1.6 seconds.
Further, when the first liquid passing time was within 2 seconds, the second liquid passing time was within 3 seconds, and the third liquid passing time was within 5 seconds, it was judged that the liquid passing property was good.

(6) Liquid return property The liquid return property is evaluated using a sample that has been repeatedly measured three times in the above-mentioned “nonwoven fabric liquid permeability”.
(A) After repeating the measurement three times with the above-mentioned "liquid permeability of non-woven fabric", the current-carrying liquid permeable plate is removed, and a weight having a size of 100 x 100 mm and a mass of 4 kg is placed on the sample and filter paper. Let stand for a minute and let the filter paper soak in saline.
(B) After 3 minutes, remove the weight, place two 125 mm × 125 mm filter papers for liquid return measurement (pickup paper “ERT-MED Hollingworth & Vose”) on top of each other, and place them on top of it. Place a weight with a mass of 4 kg again and let stand for 2 minutes. The mass (W1) of the two sheets of the filter paper for liquid return measurement is measured and recorded in advance.
(C) After 2 minutes, the weight is removed, and the mass (W2) of the two filter papers is measured and recorded.
(D) The liquid return amount (R) is calculated by the following formula.
・ R = W1-W2
When the liquid return amount (R) was 150 mg or less, it was judged that the liquid return was good.

(7) Powder removal property 0.5 g of commercially available SAP is sprayed on a circular non-woven fabric with a diameter of 76.2 mm, and a weight (mass 8.08 g, cylindrical shape with a diameter of 10.9 mm) is dropped 20 times from the non-woven fabric. It was lowered and the mass of SAP that fell off from the non-woven fabric was measured. This was repeated 3 times, and the average shedding rate was calculated. When the amount of powder dropped was 20 mg or less, it was judged that the liquid return was good.

[Example 1]
(Heat-fused non-woven fabric layer (A))
Polyethylene terephthalate (PET) having a melting point of 260 ° C. and an intrinsic viscosity of 0.65 dl / g was used as the core component, and high-density polyethylene (HDPE) having a melting point of 130 ° C. and an MFR of 18 g / 10 minutes was used as the sheath component. A laminated fiber web was formed through a carding process using a core-sheath composite fiber having a core-sheath composite mass ratio of 50/50, an average single fiber diameter of 16.3 μm, and a cut length of 38 mm as raw cotton. Next, the obtained laminated fiber web was heat-treated for 12 seconds under the conditions of a temperature of 130 ° C. and a hot air volume of 3.3 m / min using a heat treatment machine to obtain a non-woven fabric. The characteristic values of this heat-bondable non-woven fabric were measured and shown in Table 1.

(Ultrafine fiber non-woven fabric layer (B))
As a copolymerized polyester resin, a copolyethylene terephthalate having a number average molecular weight of 5500 and a copolymerization amount of 12% by mass was melted by an extruder to form a discharge hole having a pore diameter of 0.4 mm. Using a mouthpiece (hole pitch: 1 mm, number of holes: 151 holes) arranged in a straight line, spinning was performed by a melt blow method at a spinning temperature of 300 ° C. and a single hole discharge rate of 0.30 g / min. Then, the hot air was blown onto the yarn under the conditions of the hot air temperature of 320 ° C. and the hot air pressure of 0.18 MPa, and collected on the heat-sealing non-woven fabric layer. At this time, the characteristic values of the melt-blown non-woven fabric separately collected on the collection net under the same conditions were measured and shown in Table 1.

(Laminated non-woven fabric)
The heat-bondable non-woven fabric (A) and the ultrafine fiber non-woven fabric (B) obtained above are heat-treated for 12 seconds under the conditions of a temperature of 160 ° C. and a hot air volume of 3.3 m / min using a heat treatment machine, and the laminated non-woven fabric is used. Got Table 1 shows the evaluation results of the obtained laminated non-woven fabric.

[Example 2]
A melt-blown nonwoven fabric was obtained by the same method as in Example 1 except that the air pressure was set to 0.15 MPa. Using this, the characteristic values of the laminated nonwoven fabric obtained by the same method as in Example 1 were measured and shown in Table 1.

[Example 3]
A melt-blown nonwoven fabric was obtained by the same method as in Example 1 except that the nozzle temperature was 290 ° C. and the air pressure was 0.15 MPa. Using this, the characteristic values of the laminated nonwoven fabric obtained by the same method as in Example 1 were measured and shown in Table 1.

[Example 4]
A melt-blown nonwoven fabric was obtained by the same method as in Example 1 except that a raw material having a copolymerization amount of 8% by mass of the polyethylene glycol contained was used. Using this, the characteristic values of the laminated nonwoven fabric obtained by the same method as in Example 1 were measured and shown in Table 1.

[Comparative Example 1]
A melt-blown non-woven fabric was obtained by the same method as the ultrafine fiber non-woven fabric (B) of Example 1. The characteristic values of this non-woven fabric were measured and shown in Table 1.

[Comparative Example 2]
A heat-sealing nonwoven fabric was obtained by the same method as the heat-sealing nonwoven fabric (A) of Example 1. The characteristic values of this non-woven fabric were measured and shown in Table 1.

[Comparative Example 3]
Polypropylene (melting point 162 ° C.) was used as a raw material, and a melt-blown nonwoven fabric was obtained by the same method as that of the ultrafine fiber nonwoven fabric of Example 1 except that the nozzle temperature was set to 230 ° C. Using this, the characteristic values of the laminated nonwoven fabric obtained by the same method as in Example 1 were measured and shown in Table 1.

A laminated non-woven fabric in which a heat-bondable non-woven fabric layer (A) and an ultrafine fibrous non-woven fabric layer (B) are laminated, and the fibers (Fa) constituting the heat-bondable non-woven fabric layer (A) are at least the first. The fiber (Fb) constituting the ultrafine fibrous nonwoven fabric layer (B) is composed of at least a composite fiber (Fa1) composed of the thermoplastic resin composition (Pa11) of 1 and the thermoplastic resin composition (Pa12) of the second. However, the polyester-based resin is composed of fibers made of a polyester-based resin, in which polyethylene glycol is copolymerized in a range of 5% by mass or more and 40% by mass or less, and the average single fiber diameter thereof is 0.1 μm or more. The laminated nonwoven fabrics of Examples 1 to 4 having a thickness of 0 μm or less and a ratio of the heat-sealing nonwoven fabric layer (A) in the thickness direction of 70% or more and 98% or less are excellent in liquid permeability and liquid. The amount of return was small, and the powder falling prevention property was also excellent.

On the other hand, Comparative Example 1, which is a single ultrafine fibrous nonwoven fabric made of a hydrophilic polymer, has excellent liquid permeability, but has a large amount of liquid return, and Comparative Example 2, which is a single heat-sealing fiber layer, has a large amount of powder falling off and further polyolefin. In Comparative Example 3, which is an ultrafine fiber non-woven fabric made of a based resin, the liquid permeability was inferior.

1: Heat-bondable non-woven fabric layer (A)
2: Ultrafine fiber non-woven fabric layer (B)
11: Fibers (Fa) constituting the heat-bondable non-woven fabric layer (A)
21: Fibers (Fb) constituting the ultrafine non-woven fabric layer (B)

Claims (4)

A laminated non-woven fabric in which a heat-bondable non-woven fabric layer (A) and an ultrafine fibrous non-woven fabric layer (B) are laminated, and at least the first fiber (Fa) constituting the heat-bondable non-woven fabric layer (A). The fiber (Fb) constituting the ultrafine fibrous nonwoven fabric layer (B) is composed of at least a composite fiber (Fa1) composed of the thermoplastic resin composition (Pa11) of 1 and the thermoplastic resin composition (Pa12) of the second. However, the polyester-based resin is composed of fibers made of a polyester-based resin, in which polyethylene glycol is copolymerized in a range of 5% by mass or more and 40% by mass or less, and the average single fiber diameter thereof is 0.1 μm or more. A laminated non-woven fabric having a thickness of 0 μm or less and having a ratio of the heat-sealing nonwoven fabric layer (A) in the thickness direction of 70% or more and 98% or less. The laminated nonwoven fabric according to claim 1, wherein the average single fiber diameter of the composite fiber (Fa1) is 7.0 μm or more and 24.0 μm or less. The laminate according to claim 1 or 2, wherein the fiber (Fa) constituting the heat-sealing nonwoven fabric layer (A) further contains one or more kinds of fibers (Fa2) in addition to the composite fiber (Fa1). Non-woven fabric. The laminated nonwoven fabric according to any one of claims 1 to 3, wherein the melting point of the first thermoplastic resin composition (Pa11) is 10 degrees or more higher than the melting point of the second thermoplastic resin composition (Pa12).

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