TW201941928A - Laminated non-woven fabric - Google Patents

Abstract

The present invention provides a non-woven fabric that: comprises fibers comprising a polyolefin-based resin; and has water resistance, flexibility, and excellent workability. This laminated non-woven fabric has laminated therein a spun-bond non-woven fabric layer and a melt-blow non-woven fabric layer. The spun-bond non-woven fabric layer comprises complex fibers comprising a thermoplastic resin (A1) and a polyethylene-based resin (A2). The thermoplastic resin (A1) is either a polyolefin-based resin (A1a) or a polyester-based resin (A1b). The melt-blow non-woven fabric layer comprises fibers comprising a polyolefin-based resin (B). In addition, the average single fiber diameter of the complex fibers in the spun-bond non-woven fabric layer is 6.5-11.9 [mu]m and the complex viscosity of the spun-bond non-woven fabric layer measured at 230 DEG C and 6.28 rad/sec is no more than 100 Pa.sec.

Description

   Laminated non-woven fabric   

The present invention relates to a laminated nonwoven fabric. The laminated nonwoven fabric of the present invention is made by laminating a spunbond nonwoven fabric layer composed of composite fibers and a melt blown nonwoven fabric layer, and has excellent water resistance and softness. The material is excellent in moldability.

In recent years, non-woven fabrics have been used in various applications, and they are expected to grow in the future. Nonwovens are widely used in industrial materials, civil materials, construction materials, living materials, agricultural materials, sanitary materials, and medical materials.

The use of non-woven fabrics has attracted attention. In recent years, in wooden houses and other buildings, a ventilation layer is provided between an outer wall material and a heat insulation material, and a ventilation layer construction method that discharges moisture that has penetrated into the wall body to the outside through the ventilation layer is spreading. In this breathable layer construction method, as a house covering material that has both water resistance to prevent rainwater from penetrating from the outside of the building, and moisture-permeable waterproof sheet that releases moisture generated in the wall body to the outside, it is made of textile. Non-woven fabric.

Although the spunbond nonwoven fabric has a feature of excellent moisture permeability from the viewpoint of its structure, it has a problem of poor water resistance. Therefore, a spunbonded nonwoven fabric and a film excellent in water resistance are laminated and integrated to form a moisture-permeable waterproof sheet, which is used as a housing covering material.

The housing cladding material is constructed by fixing staples (also known as nail gun needles and staples) to the substrate. It is required to have long-term durability, excellent weather resistance under high temperature and low temperature conditions, and durability It has excellent durability (hydrolysis resistance) and moldability during construction.

In the past, as a moisture-permeable waterproof sheet used for such a house covering material, a house covering material has been proposed. In order to achieve a good balance between moisture permeability and water resistance, a unit fiber having a diameter of 3 to 28 microns is used. Polyester-based non-woven fabric having an area weight of 5 to 50 g / m ² , and a non-woven fabric is laminated with a film having a thickness of 7 to 60 μm including a block copolymerized polyester having a hard segment and a soft segment (see Patent Document 1) ).

Prior art literature Patent literature

Patent Document 1 Japanese Patent Publication No. 3656837

However, the conventional housing cladding material is a laminated body of a non-woven fabric and a film, and therefore has problems of being hard and having poor formability. The hardness of the sheet is caused by the film. Although it is an effective means to reduce the ratio of the laminated film, from the viewpoint of water resistance, there is a limit to the reduction of the film ratio.

Therefore, the object of the present invention is to solve the above problems, and an object of the present invention is to provide a non-woven fabric which has both water resistance and high flexibility, and has excellent moldability such as heat adhesion even without a conventional film.

The present inventors repeated their intensive and diligent review in order to achieve the above-mentioned objective, and as a result, they obtained the following knowledge: By using a spunbond nonwoven fabric layer composed of two or more different types of fibers containing polyolefin resin, and containing The laminated non-woven fabric formed by laminating a melt-blown non-woven fabric composed of fibers of a polyolefin-based resin can appropriately control the fluidity of the fibers constituting the respective non-woven fabric layers, and can have high flexibility and improve the mechanical properties of the laminated non-woven fabric. In addition, it was also found that the laminated nonwoven fabric can be provided with a high level of water resistance, softness, and workability mainly composed of thermal adhesiveness.

The present invention has been completed based on such knowledge and knowledge. According to the present invention, the following inventions can be provided.

The laminated nonwoven fabric of the present invention is a laminated nonwoven fabric formed by laminating a spunbond nonwoven fabric layer and a meltblown nonwoven fabric layer. The spunbond nonwoven fabric layer is composed of a composite fiber including a thermoplastic resin (A1) and a polyethylene resin (A2). The thermoplastic resin (A1) is a polyolefin-based resin (A1a) or a polyester-based resin (A1b), and the melt-blown nonwoven fabric layer is made of fibers containing a polyolefin-based resin (B), and further, the spunbond The average single fiber diameter of the composite fibers of the nonwoven fabric layer is 6.5 to 11.9 μm, and the complex viscosity of the spunbonded nonwoven fabric layer measured at 230 ° C. and 6.28 rad / sec is 100 Pa · sec or less.

According to a preferred aspect of the laminated nonwoven fabric according to the present invention, the water pressure resistance per unit area weight is 15 mmH ₂ O / (g / m ² ) or more.

According to a preferred aspect of the laminated nonwoven fabric according to the present invention, the melt flow rate of the fiber containing the polyolefin-based resin (A1) is 155 to 850 g / 10 minutes.

According to a preferred aspect of the laminated nonwoven fabric according to the present invention, the content of the meltblown nonwoven fabric layer is 1 mass% or more and 15 mass% or less with respect to the mass of the laminated nonwoven fabric.

According to a preferred aspect of the laminated non-woven fabric according to the present invention, the surface roughness SMD according to the KES method on at least one side is 1.0 to 2.6 μm.

According to a preferred aspect of the laminated non-woven fabric according to the present invention, the average friction coefficient MIU according to the KES method on at least one side is 0.1 to 0.5.

According to a preferred aspect of the laminated non-woven fabric according to the present invention, the average friction coefficient change MMD according to the KES method on at least one side is 0.008 or less.

According to a preferable aspect of the laminated nonwoven fabric according to the present invention, the polyolefin-based resin (A2) contains a fatty acid amido compound having a carbon number of 23 to 50.

According to a preferred aspect of the laminated non-woven fabric according to the present invention, the added amount of the aforementioned fatty acid amidine compound is 0.01 to 5.0% by mass.

According to a preferred aspect of the laminated non-woven fabric according to the present invention, the aforementioned fatty acid amido compound is ethynylbisstearate.

According to the present invention, a laminated nonwoven fabric can be obtained, which is formed by laminating a spunbond nonwoven fabric layer composed of a composite fiber and a meltblown nonwoven fabric layer composed of a polyolefin resin-containing fiber, and has water resistance and softness. The composite fiber is excellent in processability, and the composite fiber includes a polyethylene-based resin and a polyolefin-based or polyester-based resin. Due to these characteristics, the laminated nonwoven fabric of the present invention is particularly suitable for use as a building material such as a moisture-permeable waterproof sheet.

Since the laminated nonwoven fabric of the present invention is excellent in water resistance, when it is used as a moisture-permeable waterproof sheet, compared with the conventional laminated nonwoven fabric, the weight per unit area can be reduced.

Furthermore, in addition to reducing the weight of the films laminated for the purpose of water resistance, it can also be used in applications requiring high water resistance, which were difficult to apply to conventional laminated nonwovens.

Furthermore, since it is excellent in softness, when it is used as a building material, wrinkles are unlikely to occur particularly in the step of bonding, and moldability is good.

(a) ‧‧‧Core

(b) ‧‧‧ sheath

(c) ‧‧‧ first component

(d) ‧‧‧ 2nd component

FIG. 1 is a schematic cross-sectional view illustrating a cross section of a composite fiber constituting the nonwoven fabric of the present invention.

Fig. 2 is a schematic cross-sectional view illustrating a cross-section of another composite fiber constituting the nonwoven fabric of the present invention.

Fig. 3 is a schematic cross-sectional view illustrating a cross section of another composite fiber constituting the nonwoven fabric of the present invention.

A form for implementing the invention

The laminated non-woven fabric of the present invention is a laminated non-woven fabric, which is a laminated non-woven fabric formed by laminating a spunbond non-woven fabric layer and a meltblown non-woven fabric layer. The spunbond non-woven fabric layer is composed of a thermoplastic resin (A1) and a polyethylene resin (A2). ) Is composed of composite fibers, the thermoplastic resin (A1) is a polyolefin-based resin (A1a) or a polyester-based resin (A1b), and the melt-blown nonwoven fabric layer is made of fibers containing a polyolefin-based resin (B), The average single fiber diameter of the composite fibers of the spunbond nonwoven fabric layer is 6.5 to 11.9 μm, and the complex viscosity of the spunbond nonwoven fabric layer measured at 230 ° C. and 6.28 rad / sec is 100 Pa · sec or less. The details are described below.

    [Thermoplastic resin (A1), (A2), polyolefin resin (B)]    

In the laminated non-woven fabric of the present invention, a thermoplastic resin (A1) and a polyethylene-based resin (A2) are used for the composite fibers constituting the spunbonded non-woven fabric layer.

Among them, a polyolefin resin (A1a) or a polyester resin (A1b) is used for the thermoplastic resin (A1).

As the polyolefin-based resin (A1a), a polyolefin containing an olefin having 2 to 10 carbon atoms is preferably used. Specific examples include ethylene, propylene, 1-butene, 1-pentene, 1-hexane, 4-methyl-1-pentene, 1-octene, and their monomers and other α- Copolymers of olefins, etc. These can be used individually by 1 type or in combination of 2 or more types. Among these, a polypropylene-based resin is preferably used because of its strength and excellent dimensional stability during the production of sanitary materials.

Regarding the polyolefin resin (A1a) used in the present invention, when a polypropylene resin is used, the proportion of the homopolymer of propylene is preferably 60% by mass or more, more preferably 70% by mass or more, and even more preferably 80% by mass. the above. By setting it as the said range, a good spinnability can be maintained and intensity | strength can be improved.

The polyester resin (A1b) is a polyester containing an acid component and an alcohol component. Examples of the acid component include aromatic carboxylic acids such as terephthalic acid, isophthalic acid, and phthalic acid; aliphatic dicarboxylic acids such as adipic acid or sebacic acid; and cyclohexanecarboxylic acids. Cycloaliphatic dicarboxylic acid and the like. As the alcohol component, ethylene glycol, diethylene glycol, polyethylene glycol, and the like can be used.

Examples of polyester resins include polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate, and polyethylene naphthalate. , Polylactic acid, polybutylene succinate, etc., and copolymers of these. By doing so, the strength of the laminated non-woven fabric is further improved, and when used for covering the house, the fixing strength using the staple can be improved. Among them, polyethylene terephthalate is preferably used because high mechanical properties can be obtained.

On the other hand, examples of the polyethylene-based resin (A2) used in the present invention include a homopolymer of ethylene or a copolymer of ethylene and various α-olefins. Examples of the polyethylene-based resin (A2) include medium-density, high-density, and linear low-density polyethylene (hereinafter, sometimes referred to as LLDPE). They are preferably used because they have excellent spinnability. LLDPE.

As the polyethylene-based resin used in the present invention, a mixture of two or more kinds may be used, and branching components different from ethylene may be copolymerized, such as butene, hexene, 4-methylpentene, heptene, and the like. Polyethylene resins of α-olefins such as octene, or resin compositions further containing a thermoplastic elastomer or the like.

In the polyethylene resin used in the present invention, as long as the effects of the present invention are not impaired, commonly used antioxidants, weather-resistant stabilizers, light-resistant stabilizers, antistatic agents, anti-fogging agents, and anti-staining agents can be added as needed. Additives such as antiblocking agents, slip agents, nucleating agents and pigments, or other polymers.

Further, when spinning the fibers described later, in order to prevent uneven viscosity from occurring, the fiber fineness was made uniform, and the fiber diameter was further refined as described later. The resin used was also decomposed to adjust the MFR. However, for example, it is preferable not to add a free radical agent such as a peroxide, especially a dialkyl peroxide. When this method is used, in addition to uneven viscosity and fineness unevenness, it becomes difficult to fully refine the fiber diameter, and there is also a deterioration in spinnability due to uneven viscosity or bubbles caused by decomposition of gas. Happening.

The melting point of the polyethylene resin used in the present invention is preferably 80 to 160 ° C, and more preferably 100 to 140 ° C. When the melting point is preferably 80 ° C. or higher, and more preferably 100 ° C. or higher, practical heat resistance can be easily obtained. In addition, the melting point is preferably 160 ° C. or lower, and more preferably 140 ° C. or lower. This makes it easy to adhere strongly to the polypropylene-based resin, and makes it easy to spin by continuously threading.

The polyolefin-based resin (B) constituting the fibers constituting the melt-blown nonwoven fabric layer is the same as the polyolefin-based resin (A1a), and it is preferable to use a polyolefin containing an olefin having 2 to 10 carbon atoms. Among these, a polypropylene-based resin is preferably used because of its strength and excellent dimensional stability during the production of sanitary materials.

The thermoplastic resin (A1), the polyolefin resin (A2) and the polyolefin resin (B) of the fibers constituting the meltblown nonwoven layer of the composite fibers constituting the spunbond nonwoven fabric layer of the present invention are melts showing the flow characteristics The flow rate (sometimes referred to as MFR) is a value measured by ASTM D1238 (Method A).

In addition, according to the above specifications, for example, the polypropylene system is specified to be measured at a load: 2.16 kg and temperature: 230 ° C; the polyethylene system is specified to be measured at a load: 2.16 kg and temperature: 190 ° C. The measurement conditions for the polyester in the present invention are measured at a load of 2.16 kg and 280 ° C.

First, the MFR of the thermoplastic resin (A1) constituting the fibers of the aforementioned spunbond nonwoven fabric layer is preferably 155 to 850 g / 10 minutes. By setting the MFR to 155 to 850 g / 10 minutes, preferably to 155 to 600 g / 10 minutes, and more preferably to 155 to 400 g / 10 minutes, the fiber thinning behavior during spinning of the spunbond nonwoven layer is achieved. Stable, it can be stably spun even if it is stretched at a fast spinning speed in order to improve productivity. In addition, by stabilizing the thinning behavior, it is possible to suppress the sloshing of the yarn, thereby making it difficult to cause unevenness in the trapped sheet shape. Furthermore, since the fiber can be stretched stably at a fast spinning speed, the fiber can be aligned and crystallized to form a fiber having high mechanical strength.

In addition, it is also considered that the MFR of a thermoplastic resin is adjusted by blending two or more types of resins having different MFRs at an arbitrary ratio. However, at this time, the MFR of the resin blended with the main thermoplastic resin is preferably 10 to 1000 g / 10 minutes, more preferably 20 to 800 g / 10 minutes, and still more preferably 30 to 600 g / 10 minutes. By setting it as the said range, it can prevent that a viscosity nonuniformity and a fineness nonuniformity generate | occur | produce partially in the blended thermoplastic resin, and spinnability deteriorates.

The melt flow rate (MFR) of the polyethylene resin (A2) used in the present invention is preferably 50 to 200 g / 10 minutes. The MFR is preferably set to 50 to 200 g / 10 minutes, more preferably 60 to 180 g / 10 minutes, and even more preferably 70 to 150 g / 10 minutes, even at high spinning speeds for improving productivity. Elongation is also easy to follow deformation because of its low viscosity, and it enables stable spinning. Further, by stretching at a high spinning speed and performing orientation crystallization of the fibers, fibers having high mechanical strength can be produced.

In addition, it is also considered that the MFR of the polyethylene-based resin (A2) is adjusted by blending two or more types of resins having different MFRs at an arbitrary ratio. However, at this time, the MFR of the resin blended with the main polyethylene resin is preferably 10 to 1000 g / 10 minutes, more preferably 10 to 800 g / 10 minutes, and even more preferably 10 to 600 g / 10 minutes. . By setting it as the said range, the non-uniformity of a viscosity, non-uniformity of a fineness, or deterioration of spinnability in the polyethylene resin (A2) blended can be prevented.

The MFR of the polyolefin-based resin (B) constituting the fibers of the melt-blown nonwoven fabric layer is preferably 200 to 2500 g / 10 minutes. By setting the MFR to be preferably 200 to 2500 g / 10 minutes, more preferably 400 to 2000 g / 10 minutes, and still more preferably 600 to 1500 g / 10 minutes, stable spinning becomes easy, and it is possible to obtain Fibers containing a polyolefin resin (B) at a level of several μm.

In the laminated nonwoven fabric of the present invention, it is important that the complex viscosity of the spunbond nonwoven fabric layer measured at 230 ° C and 6.28 rad / sec is 100 Pa · sec or less. By setting it as the said range, even if it stretches at a high spinning speed in order to improve productivity, since viscosity is low, it can follow deformation | transformation easily, and can spin stably. Further, by stretching at a high spinning speed and performing orientation crystallization of the fibers, fibers having high mechanical strength can be produced. The complex viscosity of the spunbond nonwoven fabric layer can be adjusted by the type of polyolefin resin such as polyethylene resin or polypropylene resin, and when using a plurality of types of resins with different complex viscosities, they can be mixed by mixing The mass ratio at the time of plural types of resins is adjusted.

The complex viscosity (Pa‧sec) of the spunbonded nonwoven fabric layer of the present invention is measured by the following conditions using a dynamic viscoelasticity measuring device based on "3.3 complex shear viscosity" according to JIS K 7244-10 (2005). Value.

(1) Measuring fixture: Φ20mm parallel plate

(2) Clearance of the above parallel plates: 0.5mm

(3) Measurement temperature: 230 ° C

(4) Strain: 34.9%

(5) Vibration number: 0.3 ~ 63rad / sec

In the composite fiber comprising a thermoplastic resin (A1) and a polyethylene-based resin (A2) constituting the spunbonded nonwoven fabric layer of the present invention, the entire resin constituting the composite fiber is taken as 100% by mass, and the polyethylene-based resin (A2) The mass ratio is preferably 20 to 50% by mass, and the mass ratio of the thermoplastic resin (A1) is 50 to 80% by mass is a preferred aspect. By setting the mass ratio of polyethylene to preferably 20 to 50% by mass, and more preferably 25 to 40% by mass, it has sufficient bonding strength and can be made into flexible composite fibers. In addition, by setting the mass ratio of the thermoplastic resin (A1) to preferably 50 to 80% by mass, and more preferably 60 to 75% by mass, it is possible to produce a composite fiber having a strength that can be used practically.

In the thermoplastic resin (A1), polyethylene resin (A2), and polyolefin resin (B) used in the present invention, as long as the effects of the present invention are not impaired, commonly used antioxidants and weather resistance can be added as needed. Additives such as stabilizers, lightfast stabilizers, antistatic agents, anti-fog agents, anti-sticking agents, slip agents, nucleating agents and pigments, or other polymers.

The melting point of the thermoplastic resin (A1) or polyethylene resin (A2) used in the present invention is preferably 80 to 200 ° C, more preferably 100 to 180 ° C, and still more preferably 120 to 180 ° C. When the melting point is preferably 80 ° C. or higher, more preferably 100 ° C. or higher, and further preferably 120 ° C. or higher, it becomes easy to obtain practical heat resistance. Moreover, the melting point is preferably 200 ° C. or lower, and more preferably 180 ° C. or lower, which makes it easy to cool the yarn discharged from the spinning nozzle, suppresses fusion of the fibers, and makes stable spinning easier. .

The melting point of the polyolefin-based resin (B) used in the present invention is preferably 80 to 200 ° C, more preferably 100 to 180 ° C, and still more preferably 120 to 180 ° C. When the melting point is preferably 80 ° C. or higher, more preferably 100 ° C. or higher, and further preferably 120 ° C. or higher, it becomes easy to obtain practical heat resistance. Moreover, the melting point is preferably 180 ° C. or lower, and more preferably 150 ° C. or lower, which makes it easy to cool the yarn discharged from the spinning nozzle, suppresses fusion between the fibers, and makes stable spinning easier. .

In the laminated nonwoven fabric of the present invention, in order to improve sliding properties and softness, a preferable aspect is that the polyethylene resin (A2) constituting the spunbonded nonwoven fabric contains a fatty acid amidine compound having a carbon number of 23 to 50. .

By setting the carbon number of the fatty acid amido compound to preferably 23 or more, and more preferably 30 or more, it is possible to prevent the fatty acid amido compound from excessively exposing the surface of the fiber, and to make it excellent in spinnability and processing stability, and maintain high production. Sex. On the other hand, by setting the carbon number of the fatty acid amido compound to 50 or less, and more preferably to 42 or less, the fatty acid amido compound can be easily moved to the fiber surface, and it is possible to impart slidability and softness to the laminate. Not woven.

Examples of the fatty acid amide compounds having a carbon number of 23 to 50 used in the present invention include saturated fatty acid monoamine compounds, saturated fatty acid diamine compounds, unsaturated fatty acid monoamine compounds, and unsaturated fatty acid diamines. Amine compounds, etc.

Specifically, as the fatty acid ammonium compound having a carbon number of 23 to 50, ammonium tetracosamate, ammonium hexacosanoate, ammonium octadecanoate, and ammonium tetracosenoate may be mentioned. , Ammonium tetracosatetraenoate, Ammonium tetracosaenoate, Ammonium dilaurate, Methylamine dilaurate, Methylamine distearate, Ethylbishydroxystearate, Ethylenedisuccinate, Hexamethylenebisstearate, Hexamethylenebis behenate, Hexamethylenehydroxystearate Ammonium stearate, ammonium distearyl adipate, ammonium distearyl sebacate, ammonium bisoleate, ammonium bisinaecate, and hexamethylene bisoleate Amidine and the like may be used in combination.

In the present invention, among these fatty acid ammonium compounds, it is particularly preferable to use ethylammonium stearate of a saturated fatty acid diammonium compound. Ethylene bis-stearate is melt-spinnable due to its excellent thermal stability. The polyethylene-based resin (A2) blended with this dimethyl stearate can maintain high productivity. In addition, since the sliding properties of the fibers are improved, the fibers can be uniformly dispersed during collection, which also contributes to the improvement of the smoothness of the nonwoven fabric. Therefore, when the nonwoven fabric is formed, the opening diameter of the nonwoven fabric can be reduced, and a laminated nonwoven fabric excellent in water resistance and flexibility can be obtained.

In the present invention, for the entire resin constituting the spunbond nonwoven fabric layer (a total of the thermoplastic resin (A1) and the polyethylene-based resin (A2)), the addition amount of the fatty acid amide compound is preferably 0.01 to 5.0% by mass. The spunbond nonwoven fabric layer constitutes a laminated nonwoven fabric. By setting the amount of the fatty acid amido compound to be preferably 0.01 to 5.0% by mass, more preferably 0.1 to 3.0% by mass, and still more preferably 0.1 to 1.0% by mass, it is possible to maintain spinnability and impart moderateness. Sliding and soft.

    [Fiber]    

The composite fiber of the thermoplastic resin (A1) and the polyethylene-based resin (A2) constituting the spunbonded nonwoven fabric layer of the present invention is important in that its average single fiber diameter is 6.5 to 11.9 μm. By setting the average single fiber diameter to 6.5 μm or more, preferably 7.5 μm or more, and more preferably 8.4 μm or more, it is possible to prevent a decrease in spinnability and to form a non-woven fabric layer with good quality in a stable manner. On the other hand, by setting the average single fiber diameter to 11.9 μm or less, preferably 11.2 μm or less, and more preferably 10.6 μm or less, the flexibility and uniformity are high, even if the content ratio of the melt-blown nonwoven layer is reduced. In this case, it is also possible to make a laminated nonwoven fabric that is durable in practical use and excellent in water resistance.

Moreover, in this invention, the average single fiber diameter (micrometer) of the composite fiber which comprises the said spunbond nonwoven fabric layer is a value calculated by the following procedure.

(1) A composite fiber containing a thermoplastic resin (A1) and a polyethylene-based resin (A2) is melt-spun, drawn and extended by an ejector, and a nonwoven fabric layer is collected on a net.

(2) Collect 10 small samples (100 × 100mm) randomly.

(3) Take a photograph of the surface at a magnification of 500 to 1000 times with a microscope, and measure the width of the composite fibers from 10 of each of the samples and a total of 100 fibers.

(4) The average single fiber diameter (μm) is calculated from the average of the measured values of 100 pieces.

1 to 3 are schematic cross-sectional views illustrating a cross-section of a composite fiber constituting the spunbond nonwoven fabric of the present invention.

1 and 2 are schematic cross-sectional views showing a cross section of a core-sheath composite fiber. In FIG. 1, the centers of the core portion (a) and the sheath portion (b) are the same, and in FIG. 2, the centers of the core portion (a) and the sheath portion (b) are different.

Specifically, the core-sheath composite fiber includes a core portion (a) and a sheath portion (b), and the core portion (a) refers to at least a part of the fiber cross section surrounded by a polymer different from the core portion (a). It is arranged in a manner and extends in the length direction of the fiber. The sheath portion (b) refers to a portion arranged in a cross section of the fiber so as to surround at least a part of the core portion (a) and extending in the longitudinal direction of the fiber. The eccentric core-sheath composite fiber includes an exposed type in which the side surface of the core portion (a) is exposed and a non-exposed type in which the side surface of the core portion (a) is not exposed. In the present invention, from the viewpoint of spinning stability, a non-exposed eccentric core-sheath composite fiber is preferably used.

FIG. 3 is a schematic cross-sectional view showing a cross-section of a side by side type composite fiber. The parallel type composite fiber has a structure in which the first component (c) and the second component (d) are bonded together. These two-component bonding surfaces may be either straight or curved, and differ depending on the viscosity characteristics and the discharge ratio of the two components. The cross section of the composite fiber may be circular, or it may be made into an irregular section such as an oval.

On the other hand, the fibers containing the polyolefin-based resin (B) constituting the melt-blown nonwoven fabric of the present invention have an average single fiber diameter of preferably 0.1 to 8.0 μm, and more preferably 0.4 to 7.0 μm.

Moreover, in this invention, the average single fiber diameter (micrometer) of the fiber containing the polyolefin resin (B) which comprises a melt-blown nonwoven fabric layer is a value calculated by the following procedure.

(1) The polyolefin-based resin (B) is melt-spun and refined with hot air, and then a nonwoven fabric layer is collected on a mesh.

(2) Collect 10 small samples (100 × 100mm) randomly.

(3) Take a photograph of the surface at a magnification of 500 to 2000 times with a microscope, and measure the width of a total of 100 fibers from 10 of each sample.

(4) The average single fiber diameter (μm) is calculated from the average of the measured values of 100 pieces.

    [Non-woven layer]    

The water resistance of the laminated nonwoven fabric of the present invention can be controlled by the characteristics of the spunbond nonwoven fabric layer and the meltblown nonwoven fabric layer constituting the laminated nonwoven fabric. The water resistance of the spunbond nonwoven fabric layer can be controlled by the average fiber diameter of the composed fibers and the dispersibility of the fibers on the surface of the nonwoven fabric layer. The water resistance of the meltblown nonwoven fabric layer can be controlled by the average fiber diameter of the composed fibers or the mass ratio in the laminated nonwoven fabric, and the degree of fusion between the fibers constituting the meltblown nonwoven fabric layer.

    [Laminated non-woven fabric]    

The laminated non-woven fabric of the present invention is mainly formed by laminating a spunbond non-woven fabric layer and a meltblown non-woven fabric. With such a structure, it is possible to impart water resistance at a level higher than that required for a nonwoven fabric for a house covering material.

The laminated nonwoven fabric of the present invention preferably has a water pressure resistance per unit area weight of 15 mmH ₂ O / (g / m ² ) or more. By setting the water pressure resistance per unit area weight to preferably 15 mmH ₂ O / (g / m ² ) or more, and more preferably 17 mmH ₂ O / (g / m ² ) or more, it can be made practical to maintain durability. The laminated non-woven fabric is excellent in water resistance and excellent in flexibility, and it is also possible to reduce the weight per unit area of the laminated non-woven fabric. There is no particular limitation on the upper limit of the water pressure resistance, but the upper limit that can be achieved while maintaining the nonwoven structure is at most 30 mmH ₂ O / (g / m ² ).

In addition, the water pressure resistance per unit area weight of the laminated nonwoven fabric of the present invention is based on JIS L1092 (2009) "7.1.1 A method (low water pressure method)", and the values measured by the following procedures are used.

(1) Five test pieces with a width of 150 mm × 150 mm were collected from the laminated nonwoven fabric at regular intervals in the width direction of the laminated nonwoven fabric.

(2) A test piece is set in a clamp of a measuring device (a portion where the test piece touches water is 100 cm ² ).

(3) Raise the water level at a speed of 600 mm / min ± 30 mm / min with the water level device, and measure the water level when the water is discharged from 3 places on the back side of the test piece in mm units.

(4) The above measurement was performed on five test pieces, and the average value was taken as the water pressure resistance.

Furthermore, in the present invention, regarding the smoothness of the surface of the laminated nonwoven fabric and the goodness of the skin touch, the surface roughness SMD according to the KES method (Kawabata Evaluation System) and the KES method The average friction coefficient MIU and the change in average friction coefficient MMD according to the KES method were evaluated.

The laminated non-woven fabric of the present invention preferably has a surface roughness SMD according to the KES method of at least one side of 1.0 to 2.6 μm. By setting the surface roughness SMD according to the KES method to 1.0 μm or more, more preferably 1.3 μm or more, even more preferably 1.6 μm or more, and even more preferably 2.0 μm or more, it is possible to prevent: excessive fiber The ground is densified and feels poor, or the softness is impaired.

On the other hand, the surface roughness SMD according to the KES method is preferably 2.6 μm or less, more preferably 2.5 μm or less, even more preferably 2.4 μm or less, and still more preferably 2.3 μm or less. It is a laminated non-woven fabric with a smooth surface, small roughness, and excellent skin feel. The surface roughness SMD according to the KES method can be controlled by appropriately adjusting the average single fiber diameter or the MFR of the laminated nonwoven fabric.

In the present invention, the surface roughness SMD according to the KES method is a value measured as follows.

(1) Three test pieces having a width of 200 mm × 200 mm were collected from the laminated nonwoven fabric at regular intervals in the width direction of the laminated nonwoven fabric.

(2) Set the test piece on the sample table.

(3) Using a contact for measuring surface roughness (material: Φ0.5 mm piano wire, contact length: 5 mm) with a load of 10 gf, the surface of the test piece was scanned to measure the average deviation of the uneven shape of the surface.

(4) The above measurement is performed in the longitudinal direction (the lengthwise direction of the non-woven fabric) and the transverse direction (the widthwise direction of the non-woven fabric) of all the test pieces. Rounded off as surface roughness SMD (μm).

The average friction coefficient MIU according to the KES method of at least one side of the laminated nonwoven fabric of the present invention is preferably 0.1 to 0.5. By setting the average friction coefficient MIU to be preferably 0.5 or less, more preferably 0.45 or less, and still more preferably 0.4 or less, the sliding property of the surface of the non-woven fabric can be improved, and a laminated non-woven fabric with better skin feel can be made.

On the other hand, by setting the average friction coefficient MIU to preferably 0.1 or more, more preferably 0.15 or more, and still more preferably 0.2 or more, it is possible to prevent: excessively adding a slip agent to deteriorate spinnability, or When the yarn is caught on the mesh, the yarn slips and the texture is deteriorated. The average friction coefficient MIU of the KES method can be controlled by appropriately adjusting the average single fiber diameter or the MFR of the laminated nonwoven fabric, or by adding a slip agent to the polyethylene resin (A2) and the polyolefin resin (B).

The variation MMD of the average friction coefficient according to the KES method of at least one side of the laminated nonwoven fabric of the present invention is preferably 0.008 or less. By setting the variation MMD of the average friction coefficient to be preferably 0.008 or less, more preferably 0.0075 or less, and even more preferably 0.0070 or less, the roughness of the surface of the laminated non-woven fabric can be further reduced.

According to the change in the average friction coefficient of the KES method, the MMD can be adjusted by appropriately adjusting the average single fiber diameter or the MFR of the laminated nonwoven fabric, or by adding a slip agent to the polyethylene resin (A2) and polyolefin resin (B). control.

In the present invention, the average friction coefficient MIU and the variation MMD of the average friction coefficient according to the KES method are the values measured as follows.

(1) Three test pieces with a width of 200 mm × 200 mm were collected from the laminated nonwoven fabric at regular intervals in the width direction of the laminated nonwoven fabric.

(2) Set the test piece on the sample table.

(3) With a contact friction head (material: Φ0.5mm piano wire (20 parallel), contact area: 1 cm ² ) to which a load of 50 gf is applied, scan the surface of the test piece to measure the average friction coefficient.

(4) The above measurement is performed in the longitudinal direction (the lengthwise direction of the non-woven fabric) and the transverse direction (the widthwise direction of the non-woven fabric) of all the test pieces, and the average deviation of the total of 6 points is averaged. Rounded off as the average coefficient of friction MIU. In addition, the above-mentioned change of the average friction coefficient of a total of 6 points is further averaged, and the fourth place below the decimal point is rounded to be regarded as the change of the average friction coefficient MMD.

Moreover, in this invention, the softness | flexibility of a laminated nonwoven fabric is evaluated by air permeability and a sensory test.

The air permeability of the laminated nonwoven fabric of the present invention per unit area weight is preferably 0.5 to 10 (cc / (cm ² ‧ second)) / (g / m ² ). By setting the air permeability per unit area weight to preferably 8 (cc / (cm ² ‧ seconds)) / (g / m ² ) or less, more preferably 6 (cc / (cm ² ‧ seconds)) / (g / m ² ) or less, more preferably 4 (cc / (cm ² ‧ seconds)) / (g / m ² ) or less, which can sufficiently satisfy the air permeability required for housing covering applications and the like.

On the other hand, the amount of air per unit weight is preferably 0.2 (cc / (cm ² ‧ seconds)) / (g / m ² ) or more, and more preferably 0.4 (cc / (cm ² ‧ Seconds)) / (g / m ² ) or more, and more preferably 0.6 (cc / (cm ² ‧ seconds)) / (g / m ² ) or more, which can prevent the spunbond nonwoven fabric from being excessively densified and impairing soft Sex. The air permeability can be adjusted by the basis weight, the single fiber fineness, the basis weight of the meltblown layer, and the thermal compression bonding conditions (crimping rate, temperature, and line pressure).

In addition, in the present invention, the air permeability per unit area weight of the laminated non-woven fabric is measured in accordance with the "6.8.1 Frazier type method" in accordance with JIS L1913 (2010) using the following procedure. value.

(1) An 80 cm x 100 cm test piece was cut out of the laminated nonwoven fabric.

(2) An arbitrary 20 points in the test piece were measured at a pressure of 125 Pa of the barometer.

(3) The average of the above 20 points is calculated by rounding the second digit below the decimal point.

(4) Multiply the calculated air permeability (cc / (cm ² ‧ second)) by the weight per unit area (g / m ² ).

The laminated non-woven fabric of the present invention is more preferably 1 mass% to 15 mass%, and more preferably 2 mass% to 10 mass% with respect to the mass of the laminated nonwoven fabric. By setting the content of the melt-blown nonwoven fabric layer to 1% by mass or more, and more preferably 2% by mass or more, practical water resistance can be imparted. In addition, by setting the content of the meltblown nonwoven fabric layer to 5 mass% or less, and more preferably 10 mass% or less, the hardness unique to the meltblown nonwoven fabric can be reduced.

In addition, by setting the content of the spunbond nonwoven fabric layer in the laminated nonwoven fabric to more than 85% by mass and less than 99% by mass, a laminated nonwoven fabric having excellent flexibility and processability can be produced.

In the present invention, the content ratio of the meltblown nonwoven fabric layer is a value measured by the following procedure.

(1) Collect three test pieces with a width of 100 mm × 100 mm at regular intervals in the width direction of the laminated nonwoven fabric.

(2) Collect only the non-crimped parts of the laminated non-woven fabric.

(3) The quality of the collected test piece and the meltblown nonwoven fabric collected from the test piece were measured separately.

(4) Calculate the content ratio of the meltblown nonwoven fabric in the laminated nonwoven fabric.

The weight per unit area of the laminated nonwoven fabric of the present invention is preferably from 10 to 100 g / m ² . By setting the weight per unit area to preferably 10 g / m ² or more, more preferably 13 g / m ² or more, and still more preferably 15 g / m ² or more, a laminated nonwoven fabric capable of practical mechanical strength can be obtained.

On the other hand, the basis weight is preferably 100 g / m ² or less, more preferably 50 g / m ² or less, and even more preferably 30 g / m ² or less. When used as a housing covering material, it becomes During construction, it is suitable for the weight of the operator during hand-held operation, and can be made into a laminated non-woven fabric with excellent operability during construction. Moreover, when it is used for other uses, a laminated nonwoven fabric excellent in handleability can also be produced.

In the present invention, the weight per unit area of the laminated nonwoven fabric is a value measured by the following procedure in accordance with "6.2 Mass per Unit Area" in accordance with JIS L1913 (2010).

(1) Collect 3 pieces of 20cm × 25cm test pieces for every 1m of sample width.

(2) The respective masses (g) in the standard state of weighing.

(3) the mass per 1m ² (g / m ²⁾ represents an average value.

The thickness of the laminated nonwoven fabric of the present invention is preferably 0.05 to 1.5 mm. The thickness is preferably 0.05 to 1.5 mm, more preferably 0.08 to 1.0 mm, and still more preferably 0.10 to 0.8 mm. It has flexibility and moderate cushioning properties. When used as a housing covering material, It is suitable for the operator to hold the weight during construction. The rigidity of the nonwoven fabric is not too strong, and it can be made into a laminated nonwoven fabric with excellent operability during construction.

In the present invention, the thickness (mm) of the laminated non-woven fabric is a value measured by the following procedure in accordance with "5.1" of JIS L1906 (2000).

(1) Using a pressure head with a diameter of 10 mm, the thickness of the nonwoven fabric was measured at a thickness of ten points per 1 m at intervals of 0.01 mm in a unit of 0.01 mm under a load of 10 kPa.

(2) The third digit below the decimal point of the average of the above ten points is rounded.

The apparent density of the laminated non-woven fabric of the present invention is preferably 0.05 to 0.3 g / cm ³ . By setting the apparent density to be preferably 0.3 g / cm ³ or less, more preferably 0.25 g / cm ³ or less, and still more preferably 0.20 g / cm ³ or less, it is possible to prevent the fibers from being tightly packed to damage the laminated nonwoven fabric Softness.

On the other hand, by setting the apparent density to preferably 0.05 g / cm ³ or more, more preferably 0.08 g / cm ³ or more, and still more preferably 0.10 g / cm ³ or more, it is possible to suppress fluff and interlayer peeling. When this happens, a laminated non-woven fabric with strength, softness, and handleability that can withstand practical use is produced.

In the present invention, the apparent density (g / cm ³ ) is calculated by the following formula from the weight and thickness of the unit area before rounding, and the third place below the decimal point is rounded.

‧Apparent density (g / cm ³ ) = [Weight per unit area (g / m ² )] / [Thickness (mm)] × 10 ^-3 .

The 5% elongation stress (hereinafter, sometimes referred to as 5% modulus per unit area weight) of the laminated nonwoven fabric of the present invention is preferably 0.06 to 0.33 (N / 25mm) / (g / m ² ) , More preferably 0.13 to 0.30 (N / 25mm) / (g / m ² ), and still more preferably 0.20 to 0.27 (N / 25mm) / (g / m ² ). By setting it as the said range, a spun-bonded nonwoven fabric which is soft and excellent in touch with the strength which can be used practically can be made.

In addition, in the present invention, the stress at elongation of 5% of the weight per unit area of the laminated nonwoven fabric is based on "6.3 Tensile Strength and Elongation (ISO Method)" of JIS L1913 (2010), and the following procedure is adopted: Measured value.

(1) For each of the longitudinal direction (lengthwise direction of the nonwoven fabric) and the transverse direction (widthwise direction of the nonwoven fabric) of the nonwoven fabric, three test pieces of 25 mm × 300 mm were collected for each width of 1 m.

(2) A test piece is set in a tensile tester with a clamp interval of 200 mm.

(3) A tensile test was performed at a tensile speed of 100 mm / minute, and the stress (5% modulus) at 5% elongation was measured.

(4) Calculate the average value of the 5% modulus measured in the longitudinal and transverse directions for each test piece. Based on the following formula, calculate the 5% modulus per unit area weight, and round the third place below the decimal point.

‧Module of 5% weight per unit area ((N / 25mm) / (g / m ² )) = [Average value of 5% modulus (N / 25mm)] / Unit weight (g / m ² ).

    [Manufacturing method of laminated nonwoven fabric]    

Next, the preferable aspect of the method of manufacturing the laminated nonwoven fabric of this invention is demonstrated concretely.

The laminated non-woven fabric of the present invention is a laminated non-woven fabric including a non-woven fabric manufactured by a spunbond (S) method and a melt-blown (M) method. The manufacturing method of the laminated nonwoven fabric of the present invention can be carried out according to any method as long as it can laminate the spunbond nonwoven fabric layer and the meltblown nonwoven fabric layer. For example, a method in which fibers formed by the meltblown method are directly stacked on the nonwoven fabric layer obtained by the spunbond method to form a meltblown nonwoven layer, and then the spunbond nonwoven layer and the meltblown nonwoven layer are welded; A method of superposing a spunbond nonwoven fabric layer and a meltblown nonwoven fabric layer, and welding the two nonwoven fabric layers by heating and pressing; and using a hot-melt adhesive or a solvent-based adhesive agent to spunbond the nonwoven fabric layer and the melt A method of spraying a non-woven layer and the like. From the viewpoint of productivity, a preferable aspect is a method of directly forming a meltblown nonwoven layer on the spunbond nonwoven layer.

In addition, depending on the purpose, the spunbond nonwoven fabric layer (S) and the meltblown nonwoven fabric layer (M) can be laminated to form a structure of SM, SMS, SMMS, SSMMS, and SMSMS.

The spunbond non-woven fabric layer is made by spinning molten thermoplastic resin (polyolefin resin) as a long fiber from the spinning nozzle, and then sucking and stretching it with compressed air through an ejector, and then capturing it on a moving mesh. Gather fibers without layering.

As the shape of the spinning nozzle or the ejector, various shapes such as a circle or a rectangle can be adopted. Among them, a combination of a rectangular spinning nozzle and a rectangular ejector is preferred because the amount of compressed air is relatively small and the energy cost is excellent, it is not easy to cause fusion and friction between the yarns, and it is easy to open the fibers.

In the present invention, for example, the thermoplastic resin (A1) and the polyethylene-based resin (A2) are each melted and metered in different extruders, and are supplied to the composite spinning nozzle. The core-sheath fiber spinning nozzle of the fiber cross-section is spun as a long fiber having a core-sheath type cross section in which a polypropylene-based resin is disposed on the core component and a polyethylene-based resin is disposed on the sheath component.

The melting temperature of the thermoplastic resin (A1) and the polyethylene resin (A2) during spinning is preferably 200 to 270 ° C, more preferably 210 to 260 ° C, and still more preferably 220 to 250 ° C. By setting the spinning temperature within the above range, a stable molten state can be obtained, and excellent spinning stability can be obtained.

The spun long-fiber yarn is then cooled. As a method of cooling the spun yarn, for example, a method of forcibly blowing cold air onto the yarn, a method of naturally cooling the gas ambient temperature around the yarn, and adjusting a spinning nozzle and a jet The method of the distance between the devices or the like, or a method of combining these methods may be adopted. In addition, the cooling conditions can be appropriately adjusted by considering the discharge amount per spinning hole of the spinning nozzle, the spinning temperature, and the ambient temperature of the gas.

The cooled and solidified yarn is then drawn and stretched by the compressed air ejected from the ejector. The spinning speed is preferably 3,000 to 6,500 m / min, more preferably 3,500 to 6,500 m / min, and still more preferably 4,000 to 6,500 m / min. By setting the spinning speed to 3,000 to 6,500 m / min, high productivity is achieved, and the orientation and crystallization of the fibers are performed to obtain high-strength long fibers. Generally, if the spinning speed is increased, the spinnability is deteriorated and the yarn cannot be stably produced. However, by using a thermoplastic resin (A1) and a polyethylene resin (A2) having a specific range of MFR as described above, The intended composite fiber is spun stably.

Subsequently, the obtained long fibers were collected on a moving web without being woven into layers. In the present invention, it is also preferable that the non-woven fabric layer is temporarily abutted against the hot flat roller on one side of the mesh from the single surface thereof. By doing so, it is possible to prevent the surface layer of the non-woven layer from being rolled up or fluttering and deteriorating the texture during transportation on the web, and to improve the transportability from the yarn collection to the thermal compression bonding.

Next, the melt-blown nonwoven fabric can adopt a conventional method. First, the polyolefin-based resin (B) is melted in an extruder and supplied to a spinning nozzle. Hot air is sprayed on the yarn extruded from the spinning nozzle to refine the yarn, and then it is collected on a collection web. A non-woven layer is formed. In the melt-blown method, a complicated process is not required, a few micrometers of fine fibers can be easily obtained, and high water resistance characteristics can be easily achieved.

Secondly, the spunbond nonwoven fabric layer and the meltblown nonwoven fabric layer obtained by lamination are heat-bonded to obtain the intended laminated nonwoven fabric.

The method of thermally bonding the non-woven fabric layer is not particularly limited, and examples thereof include a heat-embossing roller having a pair of upper and lower portions each engraved (concavo-convex) on the surface of the roller, and a surface including one roller that is flat (smooth) A heat-embossing roll including a combination of a roll and another roll having an engraved (concavo-convex) roll on the roll surface, and a heat-calender roll including a combination of a pair of upper and lower flat (smooth) rolls are subjected to heat bonding. Method, or ultrasonic fusion of a horn by ultrasonic vibration, followed by a method of thermal fusion.

Among them, from the viewpoint of excellent productivity, it is possible to impart strength to a portion of the heat-bonded portion, and to maintain the feel and skin feel of a non-woven fabric at the non-bonded portion. A hot embossing roller provided with a engraving (concavo-convex portion), or a heat embossing roller comprising a combination of a roller whose surface is flat (smooth) and another roller having a engraving (concavo-convex portion) on the surface of the roller.

As the surface material of the heat embossing roller, in order to obtain a sufficient heat compression bonding effect, and to prevent the engraving (concave and convex portion) of one embossing roller from being transferred to the surface of the other roller, a preferable aspect is to make a metal roller Paired with metal rolls.

The embossing area ratio using such a hot embossing roll is preferably 5 to 30%. By setting the bonding area to preferably 5% or more, more preferably 8% or more, and even more preferably 10% or more, practical strength can be obtained as a laminated non-woven fabric. On the other hand, by setting the bonding area to be preferably 30% or less, more preferably 25% or less, and even more preferably 20% or less, moderate softness particularly suitable for use in building material applications can be obtained. Even when using ultrasonic bonding, the bonding area ratio is preferably in the same range.

The bonding area referred to here refers to the proportion of the bonding portion in the entire laminated nonwoven fabric. Specifically, when the heat bonding is performed by a pair of rollers having unevenness, it means that the convex portion of the upper roller overlaps with the convex portion of the lower roller and abuts the non-woven fabric layer (adhesion portion) in the entire laminated non-woven fabric. Proportion. In addition, when thermal bonding is performed by a roller having unevenness and a flat roller, it refers to the proportion of the portion (adhesion portion) of the non-woven layer where the convex portion of the roller having unevenness abuts against the nonwoven fabric layer. In addition, when ultrasonic bonding is performed, it refers to the ratio of the part (adhesion part) thermally welded by ultrasonic processing to the whole laminated nonwoven fabric.

The shape of the bonding portion caused by the hot embossing roll or ultrasonic bonding is not particularly limited, and for example, a circle, an oval, a square, a rectangle, a parallelogram, a rhombus, a regular hexagon, and a regular octagon can be used. Further, it is preferable that the bonding portions exist uniformly at a predetermined interval in the longitudinal direction (conveying direction) and the width direction of the laminated nonwoven fabric. By doing so, the variation in strength of the laminated nonwoven fabric can be reduced.

The surface temperature of the heat embossing roller at the time of thermal bonding is preferably in a range of -50 to -15 ° C with respect to the melting point of the polyethylene resin (A2) used. The surface temperature of the heat roller is preferably set to -50 ° C or higher, and more preferably -45 ° C or higher with respect to the melting point of the polyethylene-based resin (A2). Practical strength laminated non-woven fabric. In addition, the surface temperature of the hot embossing roll is preferably set to -15 ° C or lower, more preferably to -20 ° C or lower with respect to the melting point of the polyethylene-based resin (A2) to suppress excessive thermal adhesion. As a laminated non-woven fabric, moderate softness and processability especially suitable for the use of building materials can be obtained.

The linear pressure of the heat embossing roller at the time of heat bonding is preferably 50 to 500 N / cm. By setting the linear pressure of the roll to preferably 50 N / cm or more, more preferably 100 N / cm or more, and even more preferably 150 N / cm or more, it is possible to heat it moderately to obtain a laminate with practical strength. Not woven.

On the other hand, by setting the linear pressure of the hot embossing roll to preferably 500 N / cm or less, more preferably 400 N / cm or less, and even more preferably 300 N / cm or less, it is particularly suitable as a laminated non-woven fabric. Appropriate softness and processability for building materials.

In addition, in the present invention, for the purpose of adjusting the thickness of the laminated nonwoven fabric, before and / or after the heat bonding by the above-mentioned heat embossing roll, it can be applied by a heat calender roll including a pair of upper and lower flat rolls. Pre-pressed. The so-called upper and lower flat rollers are metal rollers or elastic rollers without unevenness on the surface of the rollers. The metal rollers can be paired with the metal rollers, or the metal rollers can be used with the elastic rollers in pairs.

The elastic roller referred to herein is a roller including a material having more elasticity than a metal roller. Examples of the elastic roller include so-called paper rollers such as paper, cotton, and aramid paper, or urethane-based resins, epoxy-based resins, silicon-based resins, and polyester-based resins. And hard rubber, and resin rollers made of these mixtures.

Examples

Next, the laminated nonwoven fabric of this invention is demonstrated concretely based on an Example. In the measurement of each physical property, the measurement is performed based on the method described above unless otherwise described.

    (1) MFR of resin (g / 10 minutes):    

The MFR of the thermoplastic resin (A1) and the polyolefin-based resin (B), and the polypropylene resin (A1a) and (B) were measured under conditions of a load of 2.16 kg and a temperature of 230 ° C. The MFR of the polyethylene resin (A2) was measured under conditions of a load of 2.16 kg and a temperature of 190 ° C.

    (2) MFR of laminated fiber (g / 10 minutes):    

The MFR of the laminated non-woven fabric was measured under conditions of a load of 2.16 kg and a temperature of 230 ° C.

    (3) Complex viscosity (Pa‧sec):    

A dynamic viscoelasticity measuring device "RHEOSOL-G3000" was used to measure the complex viscosity (Pa‧sec) of the laminated nonwoven fabric under a 20 mm parallel plate, a gap of 0.5 mm, a temperature of 230 ° C, a strain of 34.9%, and a vibration number of 0.3 to 63 rad / sec.

    (4) Spinning speed (m / min):    

From the average single fiber diameter and the solid density of the polyolefin-based resin (A) or polyolefin-based resin (B) used, the mass per 10,000m is regarded as the average single-fiber fineness (dtex), and the decimal point is The second digit below is calculated by rounding. The spinning speed was calculated based on the following formula from the average single-fiber fineness and the resin discharge amount (hereinafter, referred to as the single-hole discharge amount) (g / minute) from the single hole of the spinning nozzle set under each condition.

‧Spinning speed (m / min) = (10000 × [single hole discharge amount (g / min)]) / [average single fiber fineness (dtex)].

(5) Water pressure resistance of laminated nonwovens (mmH ₂ O):

A hydrotester "HydroTester" (FX-3000-IV type) was used.

(6) Air permeability per unit area of laminated nonwovens ((cc / cm ² ‧ seconds) / (g / m ² )):

The air permeability was measured based on the aforementioned method. In addition, the calculated air permeability (cc / (cm ² ‧ second)) is calculated from the weight per unit area (g / m ² ) obtained based on the above-mentioned method, and the second place below the decimal point is calculated by the following formula. Round up to calculate the amount of air per unit weight.

‧Breathability per unit area weight = Breathability (cc / (cm ² ‧sec)) / Unit area weight (g / m ² ).

    (7) Surface roughness SMD (μm) of laminated non-woven fabric according to KES method:    

For the measurement, an automated surface testing machine "KES-FB4-AUTO-A" manufactured by KATO TECH was used. The surface roughness SMD is measured on both sides of the laminated nonwoven fabric, and Table 1 describes the smaller value among these.

    (8) The average friction coefficient MIU of the laminated non-woven fabric according to the KES method, and the change of the average friction coefficient of the laminated non-woven fabric according to the KES method MMD:    

For the measurement, an automated surface testing machine "KES-FB4-AUTO-A" manufactured by KATO TECH was used. The average friction coefficient MIU is measured on both sides of the laminated non-woven fabric, and Table 1 shows the smaller value among these.

    (9) Softness (workability) of non-woven fabric:    

As the sensory evaluation of the touch of the nonwoven fabric, the softness was scored based on the following criteria. This series was performed by 10 persons, and the average was evaluated as a non-woven touch. The higher the number of points, the better the flexibility was judged, and the better the processability in various processes, and 4.0 or more points were considered acceptable.

    <Flexibility (workability)>    

5 points: soft (good workability)

4 o'clock: Between 5 and 3 o'clock

3 points: Normal

2 o'clock: Between 3 o'clock and 1 o'clock

1 point: Hard (poor workability).

    [Example 1]         (Spunbond nonwoven layer (lower layer))    

為0.30mm、孔深度為2mm的矩形紡嘴，在紡絲溫度為235℃、單孔吐出量為0.43g/分鐘下，以將熱塑性樹脂(A1)配置於芯成分且將聚乙烯系樹脂(A2)配置於鞘成分之芯鞘型剖面紡出。將所紡出的紗線冷卻固化後，將其在矩形噴射器中，藉由將噴射器壓力設為 0.50MPa的壓縮空氣，進行牽引、延伸，捕集在移動的網狀物上。藉此，形成由芯鞘型複合纖維的長纖維所構成之單位面積重量為8.2g/m²之紡黏不織布層。構成所形成的紡黏不織布層之纖維的特性，係平均單纖維直徑為10.9μm，由此所換算的紡絲速度為5,050m/分鐘。關於紡絲性，在1小時的紡絲中未看見斷線而為良好。 In the spunbonded nonwoven fabric layer, as the thermoplastic resin (A1), a polypropylene resin composed of a homopolymer having an MFR of 170 g / 10 minutes and a melting point of 163 ° C was used, and as the polyethylene resin (A2), MFR was used Polyethylene resin (LLDPE) consisting of 100 g / 10 minutes of homopolymer. Each of the thermoplastic resin (A1) and the polyethylene resin (A2) was melted in an extruder, and the pore diameter

A rectangular spinning nozzle having a diameter of 0.30 mm and a hole depth of 2 mm was used to dispose the thermoplastic resin (A1) as a core component and a polyethylene resin (at a spinning temperature of 235 ° C and a single-hole discharge amount of 0.43 g / min. A2) A core-sheath cross-section spun out of a sheath component. After the spun yarn was cooled and solidified, it was drawn and stretched in a rectangular ejector with compressed air at an ejector pressure of 0.50 MPa, and collected on a moving mesh. Thereby, a spunbond nonwoven fabric layer having a basis weight of 8.2 g / m ² composed of long fibers of the core-sheath composite fiber was formed. The characteristics of the fibers constituting the spunbond nonwoven fabric layer formed were that the average single fiber diameter was 10.9 μm, and the spinning speed converted from this was 5,050 m / min. Regarding spinnability, no breaks were seen during spinning for 1 hour, which was good.

    (Meltblown non-woven fabric layer)    

Next, as the polyolefin-based resin (B), a polypropylene resin composed of a homopolymer having an MFR of 1100 g / min and a melting point of 163 ° C. was used in the melt-blown nonwoven fabric layer. This polyolefin-based resin (B) was melted in an extruder and spun from a spinning nozzle having a hole diameter of 0.25 mm at a spinning temperature of 260 ° C and a single-hole discharge amount of 0.10 g / min. Then, under the conditions of an air temperature of 290 ° C. and an air pressure of 0.10 MPa, the air is sprayed onto the yarn and trapped on the aforementioned spunbond nonwoven fabric layer to form a meltblown nonwoven fabric layer. At this time, the unit area weight of the melt-blown nonwoven fabric layer additionally collected on the capture net under the same conditions was 1.6 g / m ² , and the average fiber diameter was 1.5 μm.

    (Spunbond nonwoven layer (upper layer))    

Furthermore, on the melt-blown nonwoven fabric layer, the long fibers of the core-sheath type composite fiber were collected under the same conditions as those for forming the lower spunbonded nonwoven fabric layer to form a spunbonded nonwoven fabric layer. Thereby, a spunbond-meltblown-spunbond layered web of a total basis weight of 18 g / m ² was obtained.

    (Laminated non-woven fabric)    

Next, the obtained laminated fiber web was embossed with a metal embossed with a bead pattern, followed by an embossing roller with an area ratio of 16% as the upper roller, and a metal flat roller as the lower roller. The hot embossing roller was hot-bonded under the conditions of a linear pressure of 300 N / cm and a hot-bonding temperature of 120 ° C. to obtain a laminated nonwoven fabric having a basis weight of 18 g / m ² . For the obtained laminated nonwoven fabric, the thickness, apparent density, water pressure resistance, air permeability per unit area weight, complex viscosity, surface roughness SMD, average friction coefficient MIU, and average friction coefficient change MMD were measured to further evaluate the softness of the laminated nonwoven fabric. Sex. The results are shown in Table 1.

    [Example 2]         (Spunbond non-woven layer (lower layer) ‧ (upper layer))    

Except that a polypropylene resin composed of a homopolymer having an MFR of 300 g / 10 minutes and a melting point of 163 ° C was used as the thermoplastic resin (A1), a core-sheath composite fiber was formed in the same manner as in Example 1. Composition of spunbond non-woven fabric layer. The characteristics of the long fibers constituting the spunbond nonwoven fabric layer formed were that the average single fiber diameter was 10.5 μm, and the spinning speed converted therefrom was 5,500 m / min. Regarding spinnability, no breaks were seen during spinning for 1 hour, which was good.

    (Meltblown non-woven fabric layer)    

A meltblown nonwoven fabric layer was formed in the same manner as in Example 1. The characteristics of the fibers constituting the resulting melt-blown nonwoven fabric layer were such that the average fiber diameter was 1.5 μm.

    (Laminated non-woven fabric)    

A laminated nonwoven fabric was obtained in the same manner as in Example 1. For the obtained laminated nonwoven fabric, the thickness, apparent density, water pressure resistance, air permeability per unit area weight, complex viscosity, surface roughness SMD, average friction coefficient MIU, and average friction coefficient change MMD were measured to further evaluate the softness of the laminated nonwoven fabric. Sex. The results are shown in Table 1.

    [Example 3]         (Spunbond non-woven layer (lower layer) ‧ (upper layer))    

A polypropylene resin composed of a homopolymer having an MFR of 800 g / 10 minutes and a melting point of 163 ° C was used as the thermoplastic resin (A1). In the same manner as in Example 1, a core-sheath composite fiber was formed. Composition of spunbond non-woven fabric layer. The characteristics of the long fibers constituting the spunbond nonwoven fabric layer formed were that the average single fiber diameter was 9.8 μm, and the spinning speed converted therefrom was 6,300 m / min. Regarding spinnability, no breaks were seen during spinning for 1 hour, which was good.

    (Meltblown non-woven fabric layer)    

In the same manner as in Example 2, a meltblown nonwoven fabric layer was formed.

    (Laminated non-woven fabric)    

In the same manner as in Example 1, a laminated nonwoven fabric was obtained. For the obtained laminated nonwoven fabric, the thickness, apparent density, water pressure resistance, air permeability per unit area weight, complex viscosity, surface roughness SMD, average friction coefficient MIU, and average friction coefficient change MMD were measured to further evaluate the softness of the laminated nonwoven fabric. Sex. The results are shown in Table 1.

    [Example 4]         (Spunbond non-woven layer (lower layer) ‧ (upper layer))    

A spunbonded nonwoven fabric layer was obtained in the same manner as in Example 1 except that the single-hole discharge amount was set to 0.21 g / min. The characteristics of the long fibers constituting the spunbond nonwoven fabric layer formed were that the average single fiber diameter was 7.4 μm, and the spinning speed converted therefrom was 5,700 m / min.

    (Meltblown non-woven fabric layer)    

In the same manner as in Example 1, a melt-blown nonwoven fabric web was obtained.

    (Laminated non-woven fabric)    

In the same manner as in Example 1, a laminated nonwoven fabric was obtained. For the obtained laminated nonwoven fabric, the thickness, apparent density, water pressure resistance, air permeability per unit area weight, complex viscosity, surface roughness SMD, average friction coefficient MIU, and average friction coefficient change MMD were measured to further evaluate the softness of the laminated nonwoven fabric. Sex. The results are shown in Table 1.

    [Example 5]         (Spunbond non-woven layer (lower layer) ‧ (upper layer))    

A spunbonded nonwoven fabric layer was obtained in the same manner as in Example 4 except that the basis weight was 8.5 g / m ² .

    (Meltblown fiber web)    

A melt-blown nonwoven fabric layer was obtained in the same manner as in Example 1, except that the air pressure was set to 0.20 MPa and the basis weight was set to 1.0 g / m ² . The characteristics of the fibers constituting the obtained melt-blown nonwoven fabric layer were such that the average fiber diameter was 1.0 μm.

    (Laminated non-woven fabric)    

In the same manner as in Example 1, a laminated nonwoven fabric was obtained. For the obtained laminated nonwoven fabric, the thickness, apparent density, water pressure resistance, air permeability per unit area weight, complex viscosity, surface roughness SMD, average friction coefficient MIU, and average friction coefficient change MMD were measured to further evaluate the softness of the laminated nonwoven fabric. Sex. The results are shown in Table 1.

    [Example 6]         (Spunbond non-woven layer (lower layer) ‧ (upper layer))    

Except for adding 1.0% by mass of methyl ethylstearate to the polyethylene-based resin (A2) so that the total amount of the resin constituting the spunbond nonwoven fabric layer is 0.3% by mass, it is added to the polyethylene resin (A2). In the same manner as in Example 1, a spunbond nonwoven fabric layer was obtained.

    (Meltblown non-woven fabric layer)    

In the same manner as in Example 1, a meltblown nonwoven fabric layer was obtained.

    (Laminated non-woven fabric)    

In the same manner as in Example 1, a laminated nonwoven fabric was obtained. For the obtained laminated nonwoven fabric, the thickness, apparent density, water pressure resistance, air permeability per unit area weight, complex viscosity, surface roughness SMD, average friction coefficient MIU, and average friction coefficient change MMD were measured to further evaluate the softness of the laminated nonwoven fabric. Sex. The results are shown in Table 1.

    [Comparative Example 1]         (Spunbond non-woven layer (lower layer) ‧ (upper layer))    

A spunbonded nonwoven fabric layer was obtained in the same manner as in Example 1 except that a homopolypropylene resin having an MFR of 60 g / 10 minutes and a melting point of 163 ° C was used as the thermoplastic resin (A1) and the ejector pressure was set to 0.15 MPa. The characteristics of the long fibers constituting the obtained core-sheath type nonwoven fabric layer were that the average single fiber diameter was 18.0 μm, and the spinning speed converted therefrom was 1,900 m / min. Regarding the spinnability, the number of spinning interruptions in one hour was 11 times, which was poor.

    (Meltblown non-woven fabric layer)    

In the same manner as in Example 1, a meltblown nonwoven fabric layer was obtained.

    (Laminated non-woven fabric)    

In the same manner as in Example 1, a laminated nonwoven fabric was obtained. About the obtained laminated nonwoven fabric, thickness, apparent density, water pressure resistance, air permeability per unit area weight, surface roughness SMD, average friction coefficient MIU, and variation MMD of average friction coefficient were measured, and the softness of the laminated nonwoven fabric was further evaluated. The results are shown in Table 1.

    [Comparative Example 2]         (Spunbond non-woven layer (lower layer) ‧ (upper layer))    

A spunbonded nonwoven fabric layer was obtained in the same manner as in Example 1 except that a homopolyethylene resin having an MFR of 20 g / 10 minutes was used as the polyethylene-based resin (A2) and the ejector pressure was set to 0.15 MPa. The characteristics of the long fibers constituting the obtained core-sheath type nonwoven fabric layer were an average single fiber diameter of 17.4 μm, and the spinning speed converted therefrom was 1,900 m / min. Regarding spinnability, the number of spinning interruptions in 1 hour was 9 times, which was not good.

    (Meltblown non-woven fabric layer)    

In the same manner as in Example 1, a meltblown nonwoven fabric layer was obtained.

    (Laminated non-woven fabric)    

In the same manner as in Example 1, a laminated nonwoven fabric was obtained. For the obtained laminated nonwoven fabric, the thickness, apparent density, water pressure resistance, air permeability per unit area weight, complex viscosity, surface roughness SMD, average friction coefficient MIU, and average friction coefficient change MMD were measured to further evaluate the softness of the laminated nonwoven fabric. Sex. The results are shown in Table 1.

Examples 1 to 6 have a surface roughness SMD according to the KES method of 1.8 to 2.1 μm, and a water pressure resistance per unit area weight of 15 mmH ₂ O / (g / m ² ) or more, which has excellent water resistance characteristics. In addition, the laminated nonwoven fabric of Example 6 in which stilbene distearate was added to the fibers constituting the spunbond nonwoven fabric layer has a reduced average friction coefficient, increased flexibility, and excellent processability, and is particularly suitable for housing. Non-woven fabric for covering material.

On the other hand, the laminated nonwoven fabrics of Comparative Examples 1 and 2 had a surface roughness SMD of 2.7 μm or more, which had poor water resistance and low flexibility.

Although the present invention has been described in detail using specific aspects, various changes and modifications are possible without departing from the intention and scope of the present invention, which will be apparent to those skilled in the art. In addition, this application is based on the Japanese invention patent application filed on February 28, 2018 (Japanese Patent Application No. 2018-034870) and the Japanese invention patent application filed on July 27, 2018 (Japanese Patent Application No. 2018-141051). , Its entirety is invoked by reference.

Industrial availability

The laminated non-woven fabric of the present invention has high productivity, uniform texture, smooth surface, excellent touch and skin touch, and high water resistance, so it can be suitably used as a moisture-permeable waterproof sheet and as a building material.

In addition, the use of the laminated nonwoven fabric of the present invention is not limited to the above. For example, it can be used for industrial materials such as filters, filter substrates, wire coils, etc., wallpaper, roof lining materials, sound insulation materials, heat insulation materials, and sound absorption materials. Construction materials, cladding materials, bag materials, billboards, printing substrates, etc., living materials, grass control sheets, drainage materials, foundation reinforcement materials, sound insulation materials, sound-absorbing materials, civil engineering materials, agricultural covering materials, light-shielding films Agricultural materials, such as ceiling materials, spare tire cover materials, and other vehicle materials.

Claims (10)

    A laminated nonwoven fabric is a laminated nonwoven fabric obtained by laminating a spunbond nonwoven fabric layer and a meltblown nonwoven fabric layer. The spunbond nonwoven fabric layer is composed of a composite fiber including a thermoplastic resin (A1) and a polyethylene resin (A2). The thermoplastic resin (A1) is a polyolefin-based resin (A1a) or a polyester-based resin (A1b), and the melt-blown nonwoven fabric layer is composed of a fiber containing a polyolefin-based resin (B). Furthermore, the spunbond The average single fiber diameter of the composite fibers of the nonwoven fabric layer is 6.5 to 11.9 μm, and the complex viscosity of the spunbonded nonwoven fabric layer measured at 230 ° C. and 6.28 rad / sec is 100 Pa · sec or less.     For example, the laminated non-woven fabric of claim 1 has a water pressure resistance per unit area weight of 15 mmH ₂ O / (g / m ² ) or more.     For example, the laminated non-woven fabric of claim 1 or 2, wherein the melt flow rate of the fiber containing the thermoplastic resin (A1) constituting the spunbonded non-woven fabric is 155 to 850 g / 10 minutes.         For example, the laminated non-woven fabric according to any one of claims 1 to 3, wherein the content of the meltblown non-woven layer is 1% by mass or more and 15% by mass or less with respect to the quality of the laminated non-woven fabric.         If the laminated non-woven fabric according to any one of claims 1 to 4, its surface roughness SMD according to the KES method on at least one side is 1.0 to 2.6 μm.         If the laminated non-woven fabric according to any one of claims 1 to 5, its average friction coefficient MIU according to the KES method on at least one side is 0.1 to 0.5.         If the laminated non-woven fabric according to any one of claims 1 to 6, its average friction coefficient change MMD according to the KES method on at least one side is 0.008 or less.         The laminated nonwoven fabric according to any one of claims 1 to 7, wherein the polyethylene resin (A2) contains a fatty acid amido compound having a carbon number of 23 to 50.         For example, the laminated non-woven fabric of claim 8, wherein the fatty acid ammonium compound is added in an amount of 0.01 to 5.0% by mass.         The laminated non-woven fabric according to claim 8 or 9, wherein the fatty acid ammonium compound is ammonium distearate.