Spun-bonded nonwoven fabric, production method thereof, and laminate and skin material

Abstract

To provide a spun-bonded nonwoven fabric having sufficient adiabaticity and good print visibility.SOLUTION: A spun-bonded nonwoven fabric includes fibers mainly composed of thermoplastic resin. At least one surface has an arithmetical average roughness Ra of 4.0 μm or more and 10.0 μm or less. The spun-bonded nonwoven fabric includes fibers having a fiber orientation degree of 0 degrees or more and 20 degrees or less in a proportion of 40% or more and 70% or less.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a spunbond nonwoven fabric. [Background technology]

[0002] Heat-shrinkable films have traditionally been used as display labels for containers such as PET bottles and aluminum cans. These heat-shrinkable films are required to have clear printability in order to display product names and contents. Furthermore, they are required to be able to maintain the temperature of the contents when they are hot, and to prevent moisture in the air from condensing on the container surface when the contents are colder than room temperature. For such display labels, a fiber sheet covering the surface as an insulating layer has been proposed, and nonwoven fabric sheets are used from the perspective of production costs.

[0003] For example, Patent Document 1 proposes a heat-insulating shrink tube for beverage-filled containers, which is made of a laminate sheet in which a heat-shrinkable plastic film as an outer layer and a nonwoven fabric sheet as an inner layer are laminated and joined together. According to this, the heat shrinkage force of the base film stably covers the body of the beverage-filled container, and the porous structure of the nonwoven fabric sheet laminated and integrated with this provides good heat insulation, thereby eliminating the difficulty of handling beverage-filled containers that are sold heated in stores or vending machines.

[0004] Furthermore, Patent Document 2 proposes a heat-shrinkable label formed by forming a laminate having at least a heat-shrinkable film and a nonwoven fabric into a cylindrical shape, and solvent-bonding the surface portion of the heat-shrinkable film layer at one end to the surface portion of the nonwoven fabric layer facing the heat-shrinkable film at the other end. This document describes that a heat-shrinkable label is provided which can be attached to various types of containers such as bottles and cups by heat shrinking, has a practical heat insulating effect, and can be produced by a normal solvent bonding process. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-67189 [Patent Document 2] Japanese Patent Application Laid-Open No. 2005-338304 Summary of the Invention [Problem to be solved by the invention]

[0006] The nonwoven fabrics used in the labels disclosed in Patent Documents 1 and 2 are thought to have a certain degree of heat insulation, but the visibility of printed characters and images (print visibility) is insufficient. Therefore, in order to improve visibility, it is necessary to avoid covering the entire circumference of the container with nonwoven fabric, which poses the problem of insufficient heat insulation.

[0007] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a spunbond nonwoven fabric that has sufficient heat insulation properties and good print visibility. [Means for solving the problem]

[0008] As a result of extensive research to achieve the above-mentioned objective, the inventors have discovered that when the surface roughness and degree of fiber orientation of a spunbond nonwoven fabric are within a certain range, the spunbond nonwoven fabric has sufficient heat insulation properties while providing good print visibility, and further has excellent hand-tearability when removing a label from a beverage container.

[0009] The present invention has been completed based on these findings, and provides the following inventions.

[0010] [1] A spunbond nonwoven fabric composed of fibers whose main component is a thermoplastic resin, in which at least one arithmetic mean roughness Ra is 4.0 μm or more and 10.0 μm or less, and the proportion of fibers having a fiber orientation degree of 0° or more and 20° or less is 40% or more and 70% or less.

[0011] [2] Q-max is 0.01 W / cm2 More than 0.10W / cm 2 The spunbond nonwoven fabric according to [1] above, which is as follows:

[0012] [3] The spunbond nonwoven fabric according to [1] or [2], wherein the fibers are composite fibers in which a low-melting point polymer having a melting point lower than that of a high-melting point polymer is disposed around the high-melting point polymer.

[0013] [4] The spunbond nonwoven fabric according to any one of [1] to [3], wherein the average single fiber diameter of the fibers is 5.0 μm or more and 16.0 μm or less.

[0014] [5] Weight is 5g / m 2 More than 50g / m 2 The spunbond nonwoven fabric according to any one of the above [1] to [4], which is:

[0015] [6] A laminate obtained by laminating the spunbond nonwoven fabric according to any one of [1] to [5] above and a film via an adhesive resin.

[0016] [7] A step of spinning a thermoplastic resin through an outlet hole of a spinneret and further drawing the resin by suction to obtain a long fiber; a step of causing the long fibers to align with a dispersion plate having an average inclination angle θ of 0° or more and 40° or less, and then collecting the long fibers on a moving net conveyor to obtain a fiber web; a step of preheating only one surface of the fiber web by bringing a heating surface into contact with the fiber web to obtain a preheated fiber web; a step of thermally bonding the preheated fiber web with a pair of flat rolls; The method for producing the spunbonded nonwoven fabric, the spinning speed during the suction drawing is 3000 m / min or more and 6000 m / min or less, In the preheating, the temperature of the heating surface is lower than the melting point of the thermoplastic resin by 30°C or more and 110°C or less, and the linear pressure of the heating surface is 1 N / cm or more and 100 N / cm or less, In the thermal bonding, the surface temperature of the pair of flat rolls is 30°C to 70°C lower than the melting point of the thermoplastic resin, and the linear pressure of the pair of flat rolls is 100 N / cm to 900 N / cm.

[0017] [8] A process in which a high-melting-point polymer and a low-melting-point polymer having a melting point 10°C to 110°C lower than the melting point of the high-melting-point polymer are spun through an outlet hole of a composite spinneret, and then suction-drawn to obtain a long fiber in which the high-melting-point polymer is covered with the low-melting-point polymer without exposing the high-melting-point polymer; a step of causing the long fibers to align with a dispersion plate having an average inclination angle θ of 0° or more and 40° or less, and then collecting the long fibers on a moving net conveyor to obtain a fiber web; a step of preheating only one surface of the fiber web by bringing a heating surface into contact with the fiber web to obtain a preheated fiber web; a step of thermally bonding the preheated fiber web with a pair of flat rolls; The method for producing the spunbonded nonwoven fabric, the spinning speed during the suction drawing is 3000 m / min or more and 6000 m / min or less, In the preheating, the temperature of the heating surface is lower than the melting point of the low-melting point polymer by 30°C or more and 110°C or less, and the linear pressure of the heating surface is 1 N / cm or more and 100 N / cm or less, In the thermal bonding, the surface temperature of the pair of flat rolls is 30°C to 70°C lower than the melting point of the low-melting point polymer, and the linear pressure of the pair of flat rolls is 100 N / cm to 900 N / cm. [Effects of the Invention]

[0018] According to the present invention, a spunbonded nonwoven fabric can be obtained which maintains heat retention while suppressing fiber shedding and is easy to tear by hand. [Brief explanation of the drawings]

[0019] [Figure 1]FIG. 1 is a schematic surface diagram illustrating a method for measuring the degree of fiber orientation in the spunbonded nonwoven fabric of the present invention. [Figure 2] FIG. 2 is a process diagram illustrating a method for controlling the degree of fiber orientation in the spunbonded nonwoven fabric of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0020] The spunbond nonwoven fabric of the present invention is a spunbond nonwoven fabric composed of fibers whose main component is a thermoplastic resin, and at least one arithmetic mean roughness Ra is 4.0 μm or more and 10.0 μm or less, and the proportion of fibers having a fiber orientation degree of 0° or more and 20° or less is 40% or more and 70% or less.

[0021] In the present invention, the MD direction refers to the sheet conveying direction during the production of a spunbond nonwoven fabric, i.e., the winding direction (machine direction) of a nonwoven fabric roll, and the CD direction refers to the sheet conveying direction, i.e., the direction perpendicular to the winding direction of a nonwoven fabric roll (cross direction, also called TD direction (transverse direction)). If the spunbond nonwoven fabric is not in a rolled state, for example, because it is cut, the MD direction and CD direction are determined according to the procedures shown in (i-1) to (i-4) below. (i-1) One arbitrary direction is determined within the plane of the spunbond nonwoven fabric, and a test piece 20 cm long and 3.0 cm wide is taken along that direction. (i-2) Similarly, collect test pieces 20 cm long and 3.0 cm wide in directions rotated 30°, 60°, and 90° from the direction in which the sample was taken. (i-3) Test specimens in each direction shall be measured in accordance with "6.5 Tensile strength and elongation" of JIS L1908:2000 "Geotextile testing methods." (i-4) The direction in which the measured value is highest is the MD direction of the spunbond nonwoven fabric, and the direction perpendicular to this is the CD direction. If there are two or more directions in which the tensile strength is highest, the direction perpendicular to these directions in which the tensile strength is lower is the CD direction of the spunbond nonwoven fabric, and the direction perpendicular to this is the MD direction.

[0022] The components will be described in detail below, but the present invention is not limited to the scope described below as long as it does not go beyond the gist of the present invention, and various modifications are possible within the scope of the present invention.

[0023] [Fibers made primarily of thermoplastic resin] First, the spunbond nonwoven fabric of the present invention is composed of fibers whose main component is a thermoplastic resin. Here, in the present invention, "mainly composed of a thermoplastic resin" means that the mass of the thermoplastic resin is more than 50% by mass of the total mass of the fibers.

[0024] Examples of the thermoplastic resin include polyester, polyamide, polyolefin, and mixtures or copolymers thereof. Among these, polyester is preferred because it has excellent durability such as mechanical strength, heat resistance, water resistance, and chemical resistance.

[0025] Polyesters are composed of a dicarboxylic acid component and a diol component. Examples of the dicarboxylic acid component include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, and phthalic acid, aliphatic dicarboxylic acids such as adipic acid and sebacic acid, and alicyclic dicarboxylic acids such as cyclohexanecarboxylic acid. Examples of the diol component include ethylene glycol, diethylene glycol, and polyethylene glycol.

[0026] Specific polyesters are broadly classified into polyesters containing aromatic groups and polyesters containing aliphatic groups, and examples of polyesters containing aromatic groups include polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), polyethylene naphthalate (PEN), and copolymers thereof, while examples of aliphatic polyesters include polylactic acid (PLA), polybutylene succinate (PBS), and copolymers thereof. In the nonwoven fabric of the present invention, aromatic polyesters are more preferred from the viewpoint of mechanical strength, and PET is even more preferred from the viewpoint of durability such as heat resistance and water resistance.

[0027] When a copolymer of PET is used, a preferred example of the copolymer component, in other words, the copolymer component of copolymerized PET, is isophthalic acid, because it has particularly excellent spinnability.

[0028] These thermoplastic resins can contain additives such as nucleating agents, matting agents, lubricants, pigments, mildew inhibitors, antibacterial agents, flame retardants, metal oxides, aliphatic bisamides and / or alkyl-substituted aliphatic monoamides, and hydrophilic agents, provided that the effects of the present invention are not impaired. Metal oxides, such as titanium oxide, improve spinnability by reducing surface friction of the fibers and preventing fusion between the fibers. They also improve the fusion properties of the spunbonded nonwoven fabric when fused with a heated roll. Furthermore, aliphatic bisamides and / or alkyl-substituted aliphatic monoamides, such as ethylene bisstearamide, improve the releasability between the heated roll and the nonwoven fabric web, improving transportability.

[0029] The fiber according to the present invention is preferably a composite fiber in which a low-melting polymer having a melting point lower than that of a high-melting polymer is arranged around the high-melting polymer. By using such a composite fiber, better adhesion is possible, resulting in a spunbonded nonwoven fabric with excellent smoothness, which, when used as a laminated sheet, is easy to tear by hand. Here, the terms "high-melting polymer" and "low-melting polymer" refer to the thermoplastic resins described above, namely, the thermoplastic resin with the higher melting point and the thermoplastic resin with the lower melting point, respectively, of the two thermoplastic resins contained in the composite fiber.

[0030] When the thermoplastic resin is polyester, examples of combinations of a high-melting point polymer and a low-melting point polymer (hereinafter, they may be described in the order of high-melting point polymer / low-melting point polymer) include combinations such as PET / PBT, PET / PTT, PET / polylactic acid, and PET / copolymerized PET, and among these, the combination of PET / copolymerized PET is preferably used because of its excellent spinnability.

[0031] The difference between the melting points of the high-melting-point polymer and the low-melting-point polymer (hereinafter sometimes simply referred to as the "melting point difference") is preferably 10°C or more and 110°C or less. In other words, a low-melting-point polymer having a melting point 10°C or more and 110°C or less lower than the melting point of the high-melting-point polymer is preferred. A melting point difference of preferably 10°C or more, more preferably 20°C or more, and even more preferably 30°C or more results in a spunbond nonwoven fabric with sufficiently excellent adhesiveness. Furthermore, a melting point difference of preferably 110°C or less, more preferably 100°C or less, and even more preferably 90°C or less prevents the low-melting-point polymer from fusing to the rolls used during thermal bonding, resulting in a decrease in productivity, a small arithmetic mean roughness, and a spunbond nonwoven fabric with excellent print visibility.

[0032] In the present invention, the melting point of the high-melting point polymer in the conjugated fiber is preferably in the range of 160°C or higher and 320°C or lower. When the melting point of the high-melting point polymer in the conjugated fiber is preferably 160°C or higher, more preferably 170°C or higher, and even more preferably 180°C or higher, a spunbond nonwoven fabric with excellent shape stability and durability is obtained. Furthermore, when the melting point of the high-melting point polymer in the conjugated fiber is 320°C or lower, more preferably 300°C or lower, and even more preferably 280°C or lower, a spunbond nonwoven fabric that easily conforms to the shape of a beverage container when wrapped around the container as a laminated sheet is obtained.

[0033] On the other hand, the melting point of the low-melting-point polymer in the above-mentioned conjugated fiber is preferably in the range of 10°C or higher and 110°C or lower, while ensuring the above-mentioned difference in melting points. By having the melting point of the low-melting-point polymer in the above-mentioned conjugated fiber be preferably 10°C or higher, more preferably 20°C or higher, and even more preferably 30°C or higher, the desired thermal adhesiveness can be obtained, resulting in a high-density, smooth spunbonded nonwoven fabric. Furthermore, by having the melting point of the low-melting-point polymer in the above-mentioned conjugated fiber be preferably 110°C or lower, more preferably 100°C or lower, and even more preferably 90°C or lower, the conjugated fiber becomes more flexible, resulting in a spunbonded nonwoven fabric that can easily conform to the shape of a beverage container when wrapped around the container as a laminated sheet.

[0034] In the present invention, the melting point of the thermoplastic resin is a value measured and calculated by the following method. (i) Ten small samples of approximately 3 mg each are randomly taken from the spunbond nonwoven fabric. (ii) Using a differential scanning calorimeter (for example, PerkinElmer's "DSC-2"), measurement is performed at a heating rate of 20°C / min within a temperature range of 30°C to 350°C, and the temperature at which the extreme value is obtained in the resulting melting endothermic curve is measured. (iii) Among the temperatures giving extreme values ​​in the obtained melting curve, the highest temperature is taken as the melting point (°C) of the high-melting-point polymer, and the second highest temperature is taken as the melting point (°C) of the low-melting-point polymer. (iv) The arithmetic mean of the values ​​obtained from each small sample is rounded to the nearest tenth and the resulting value is the melting point (°C) of the high-melting-point polymer and the melting point (°C) of the low-melting-point polymer.

[0035] Examples of the composite form of the composite fiber include a concentric sheath-core type, an eccentric sheath-core type, and an islands-in-sea type. Of these, the concentric sheath-core type is preferred because it allows the fibers to be fused uniformly and firmly. Furthermore, the cross-sectional shape of the composite fiber may be a circular cross-section, a flat cross-section, a polygonal cross-section, a multi-lobal cross-section, a hollow cross-section, etc. Of these, a circular cross-sectional shape is preferred.

[0036] Furthermore, the mass ratio of the high-melting point polymer to the low-melting point polymer in the fibers containing a thermoplastic resin as the main component is preferably in the range of 90:10 to 30:70, more preferably 83:17 to 40:60, thereby providing a long-fiber nonwoven fabric with excellent thermal stability, excellent thermal adhesiveness, and a smoother spunbonded nonwoven fabric.

[0037] The fibers according to the present invention preferably have an average single fiber diameter of 5.0 μm or more and 16.0 μm or less. An average single fiber diameter of preferably 10.0 μm or more, more preferably 12.0 μm or more, and even more preferably 14.0 μm or more results in a spunbond nonwoven fabric with excellent mechanical strength. On the other hand, an average single fiber diameter of preferably 16.0 μm or less, more preferably 14.0 μm or less, results in a denser spunbond nonwoven fabric, which increases the number of bonded points between fibers and provides a spunbond nonwoven fabric with sufficient mechanical strength for practical use.

[0038] Even when fibers having different fiber diameters are mixed, it is preferable that the average single fiber diameter of the fibers measured by the following procedure is within the above range.

[0039] In the present invention, the average single fiber diameter (μm) of the fibers is a value measured and calculated by the following procedure. (1) Ten small sample pieces (100 mm x 100 mm) are randomly taken from the spunbond nonwoven fabric. (2) Take a surface photograph at a magnification of 500 to 3000 times using a microscope (for example, Keyence Corporation's "VHX-D500"), and measure the diameter of 100 single fibers, 10 of which are randomly selected from each sample. (3) The arithmetic mean value of the measured values ​​of 100 fibers is rounded off to the first decimal place to calculate the average single fiber diameter (μm).

[0040] [Spunbond nonwoven fabric] The spunbond nonwoven fabric of the present invention is made of the above-mentioned fibers. The spunbond nonwoven fabric has an arithmetic mean roughness Ra of 4.0 μm or more and 10.0 μm or less on both sides. By ensuring that the arithmetic mean roughness Ra of both sides is 4.0 μm or more, preferably 5.0 μm or more, and more preferably 6.0 μm or more, the surface of the long-fiber nonwoven fabric has appropriate irregularities (voids), resulting in a spunbond nonwoven fabric with excellent print visibility. On the other hand, by ensuring that the arithmetic mean roughness Ra of both sides is 10.0 μm or less, preferably 9.0 μm or less, and more preferably 8.0 μm or less, the surface of the long-fiber nonwoven fabric can be made denser, resulting in a spunbond nonwoven fabric with good adhesiveness when laminated to a printed layer.

[0041] The arithmetic mean roughness Ra (μm) of the spunbond nonwoven fabric is a value obtained by measuring and calculating according to the following procedure. (1) Randomly collect 20 pieces of 10cm x 10cm long fiber nonwoven fabric. (2) For a randomly sampled long-fiber nonwoven fabric, a surface roughness meter (such as the Mitutoyo Corporation "Surftest SJ-210") was used to measure the surface roughness in accordance with JIS B0610:2001 "Product Geometric Characteristics Specifications (GPS) - Surface Shape: Profile Curve Method - Definition and Display of Rolling Circle Waviness" with λc = 2.5 mm and λ s The spunbond nonwoven fabric sheet is measured across a 21 mm range in the width direction under conditions of a roughness of 8 μm and a measurement speed of 0.5 mm / s, and the arithmetic mean roughness Ra is measured on both sides of 20 points of each sample in 0.1 μm increments, and the arithmetic mean is calculated. (3) The arithmetic mean value (μm) of the above measured values ​​is calculated for each surface, and the result is rounded off to one decimal place.

[0042] Furthermore, the arithmetic mean roughness Ra of one surface of the spunbonded nonwoven fabric can be adjusted to fall within the above range by adjusting the average single fiber diameter of the fibers constituting the spunbonded nonwoven fabric, and the surface temperature and linear pressure of the pair of upper and lower flat rolls in the thermal bonding step of the manufacturing method for the spunbonded nonwoven fabric, within the ranges described below.

[0043] Next, the spunbond nonwoven fabric of the present invention has a ratio of fibers having a fiber orientation of 0° to 20° (both 40% and 70%). The "ratio" here refers to the ratio by number, as described in the measurement and calculation methods below. By satisfying this requirement, the spunbond nonwoven fabric has excellent print visibility and is easy to tear when attaching and detaching labels. For the range of the ratio of fibers having a fiber orientation of 0° to 20° (hereinafter simply referred to as "MD-oriented fibers"), setting the lower limit to 40% or more, preferably 45% or more, and more preferably 50% or more improves the uniformity of the basis weight in the longitudinal direction, resulting in a spunbond nonwoven fabric with good uniformity of print visibility. On the other hand, for the range of the ratio of MD-oriented fibers, setting the upper limit to 70% or less, preferably 65% ​​or less, and more preferably 60% or less prevents extreme fiber orientation and suppresses overlapping of webs, resulting in a spunbond nonwoven fabric with a more uniform density.

[0044] In the present invention, the proportion of MD-oriented fibers in the spunbond nonwoven fabric is a value measured and calculated by the following method. (i) Randomly take 15 small sample pieces (8 mm in MD x 10 mm in CD) from the spunbond nonwoven fabric. (ii) Set the MD direction perpendicular to the observation screen using a scanning electron microscope (SEM, for example, Keyence Corporation's VHX-D500) and take a 1000x photograph. (iii) A 0° reference line (13) parallel to the MD direction (the direction of the arrow 14 in FIG. 1) of the photograph (schematically illustrated in FIG. 1) is drawn, and the fiber orientation angles relative to this line (illustrated as θ1 to θ4 in FIG. 1) are measured for 15 fibers from each sample, for a total of 225 fibers. The fiber orientation angle in the present invention is a value measured for fibers in the range of 0° to 90° relative to the 0° reference line (13), and is determined so that the angle does not indicate a negative value or exceed 90°. Only fibers with a continuous single fiber length of 150 μm or more exposed on the surface are measured. When the thermoplastic continuous filament (11) cannot be approximated by a straight line, as in the calculation of θ3 in FIG. 1, a straight line is drawn between two points on the bent convex portion of the thermoplastic continuous filament (11) within the measurement range frame (12), and the angle between this line and the 0° reference line (13) is calculated as the fiber orientation angle. (iv) The number of fibers with a fiber orientation angle between 0° and 20° (N 0-20 ) to the total number (N A ) and calculate the fiber orientation degree (F) using the following formula. F(%)=N 0-20 / N A ×100...(formula).

[0045] The degree of fiber orientation of the spunbond nonwoven fabric can be adjusted by the type of spreader board used in the process of forming the nonwoven web.

[0046] The spunbond nonwoven fabric of the present invention has a basis weight of 5 g / m 2 More than 50g / m 2 The lower limit of the basis weight range of the spunbond nonwoven fabric is preferably 5 g / m or less. Such a spunbond nonwoven fabric has excellent breathability and strength. 2 More preferably, 10 g / m 2 More preferably, 15 g / m 2By setting the weight per unit area to 1000g / m or more, the spunbonded nonwoven fabric has excellent mechanical strength and good heat retention. On the other hand, the upper limit of the weight per unit area of ​​the spunbonded nonwoven fabric is preferably 50g / m 2 Less than 40 g / m 2 or less, more preferably 30 g / m 2 If the thickness is less than or equal to the thickness of the spunbond nonwoven fabric, the spunbond nonwoven fabric can be easily torn by hand.

[0047] In the present invention, the basis weight of the spunbond nonwoven fabric is a value measured and calculated by the following procedure in accordance with "6.2 Mass per unit area" of JIS L1913:2010 "Testing methods for general nonwoven fabrics." (i) Take three 25cm x 25cm test pieces per meter of sample width. (ii) Weigh the mass (g) of each at standard conditions. (iii) The arithmetic mean value is 1 m 2 Mass per unit (g / m 2 ) and rounded to the first decimal place.

[0048] The apparent density of the spunbond nonwoven fabric of the present invention is 0.30 g / cm 3 More than 0.80g / cm 3 The lower limit of the apparent density range of the spunbond nonwoven fabric is preferably 0.30 g / cm or less. 3 More preferably, 0.35 g / cm 3 When the tensile strength is 0.80 g / cm or more, the spunbond nonwoven fabric has higher mechanical strength. On the other hand, the upper limit of the above range is preferably 0.80 g / cm. 3 or less, more preferably 0.70 g / cm 3 or less, more preferably 0.50 g / cm 3 When the above condition is satisfied, the spunbond nonwoven fabric has excellent heat retention.

[0049] In the present invention, the apparent density of the spunbond nonwoven fabric is determined by the following method. (i) The thickness (mm) of the spunbond nonwoven fabric is measured using the following procedure. (i-1) Using a thickness meter (for example, TECLOCK (registered trademark) SM-114 manufactured by TECLOCK Corporation), measure the thickness of the spunbond nonwoven fabric at 10 points at 10 cm intervals in the CD direction. If the distance in the CD direction is 100 cm or less, divide the distance in the CD direction into 10 parts and measure at 10 points at those intervals. (i-2) Calculate the arithmetic mean value (mm) of the above measurement results and round off to two decimal places. (ii) The basis weight (g / m) of the spunbond nonwoven fabric 2 ) and thickness (mm), the value calculated by the following formula will be used as the apparent density. Apparent density (g / cm 3 ) = basis weight (g / m 2 ) / Thickness (mm) / 1000 ···(Formula).

[0050] Furthermore, the spunbond nonwoven fabric of the present invention has a Q-max of 0.01 W / cm 2 More than 0.10W / cm 2 The upper limit of the Q-max range of the spunbond nonwoven fabric is preferably 0.10 W / cm or less. 2 or less, more preferably 0.07 W / cm 2 When the temperature of the container is less likely to be transmitted to the outside, the spunbond nonwoven fabric has good heat retention. On the other hand, the lower limit of the above range is preferably 0.01 W / cm or less. 2 By satisfying the above conditions, the temperature inside the container is appropriately transferred to the outside, resulting in a spunbond nonwoven fabric that is sensitive to the temperature inside.

[0051] In the present invention, the Q-max of a spunbond nonwoven fabric refers to the maximum heat flux as defined in JIS L1927:2020, "Method for evaluating the coolness of textile products," and more specifically, refers to a value measured and calculated according to this standard using a precise and rapid thermal property measuring device such as "KES-F7 Thermo Lab" manufactured by Kato Tech Co., Ltd., by the following method. (i) Take five 15cm x 15cm test pieces per meter of sample width. (ii) Set the measurement table to the same temperature as room temperature. (iii) Set the heat source plate to a temperature 10.0°C higher than room temperature. (iv) Place the test piece on the measurement table with the surface that comes into contact with the skin facing up. (v) The test piece was quickly brought into contact with the measurement part at a pressure of 1.02 kPa, and the heat flux (W / cm 2 ) is calculated. (vi) The remaining four test pieces were measured in the same manner, and the average value was used to evaluate the coolness of the spunbond nonwoven fabric (W / cm 2 )

[0052] [Manufacturing method of spunbond nonwoven fabric] Next, a method for producing the spunbonded nonwoven fabric of the present invention will be described. One preferred embodiment of the method for producing the spunbonded nonwoven fabric of the present invention is as follows: a step of spinning a thermoplastic resin through an outlet hole of a spinneret and further drawing the resin by suction to obtain a long fiber; a step of causing the long fibers to align with a dispersion plate having an average inclination angle θ of 0° or more and 40° or less, and then collecting the long fibers on a moving net conveyor to obtain a fiber web; a step of preheating only one surface of the fiber web by bringing a heating surface into contact with the fiber web to obtain a preheated fiber web; a step of thermally bonding the preheated fiber web with a pair of flat rolls; The method for producing the spunbonded nonwoven fabric, the spinning speed during the suction drawing is 3000 m / min or more and 6000 m / min or less, In the preheating, the temperature of the heating surface is lower than the melting point of the thermoplastic resin by 30°C or more and 110°C or less, and the linear pressure of the heating surface is 1 N / cm or more and 100 N / cm or less, In the thermal bonding, the surface temperature of the pair of flat rolls is 30°C to 70°C lower than the melting point of the thermoplastic resin, and the linear pressure of the pair of flat rolls is 100 N / cm to 900 N / cm.

[0053] Another preferred embodiment of the method for producing a spunbonded nonwoven fabric of the present invention is a step of spinning a high-melting-point polymer and a low-melting-point polymer having a melting point 10°C to 110°C lower than the melting point of the high-melting-point polymer through an outlet hole of a composite spinneret, and further drawing the resulting fibers under suction to obtain long fibers in which the high-melting-point polymer is covered with the low-melting-point polymer without exposing the high-melting-point polymer; a step of causing the long fibers to align with a dispersion plate having an average inclination angle θ of 0° or more and 40° or less, and then collecting the long fibers on a moving net conveyor to obtain a fiber web; a step of preheating only one surface of the fiber web by bringing a heating surface into contact with the fiber web to obtain a preheated fiber web; a step of thermally bonding the preheated fiber web with a pair of flat rolls; The method for producing the spunbonded nonwoven fabric, the spinning speed during the suction drawing is 3000 m / min or more and 6000 m / min or less, In the preheating, the temperature of the heating surface is lower than the melting point of the low-melting point polymer by 30°C or more and 110°C or less, and the linear pressure of the heating surface is 1 N / cm or more and 100 N / cm or less, In the thermal bonding, the surface temperature of the pair of flat rolls is 30°C to 70°C lower than the melting point of the low-melting point polymer, and the linear pressure of the pair of flat rolls is 100 N / cm to 900 N / cm.

[0054] Each of the above steps will be described in more detail below.

[0055] (a) Step for obtaining long fibers In one preferred embodiment of this process, a thermoplastic resin is first spun out from the nozzle of a spinneret. In another preferred embodiment, a high-melting-point polymer and a low-melting-point polymer having a melting point 10°C to 110°C lower than that of the high-melting-point polymer are spun out from the nozzle of a bicomponent spinneret. Here, the thermoplastic resin, high-melting-point polymer, and low-melting-point polymer can be those described above.

[0056] In the latter case (when a composite spinneret is used), it is preferable to melt-extrude the high-melting point polymer and the low-melting point polymer from a spinneret at a temperature above their melting points (melting point + 70°C) to form a composite long fiber in which the low-melting point polymer is arranged around the high-melting point polymer.

[0057] The shape of the nozzle holes of the spinneret through which the molten thermoplastic resin is extruded may be circular, elliptical, polygonal, multi-lobed, or a combination thereof, depending on the cross-sectional shape of the fiber. Among these, the use of a nozzle hole with a circular cross-sectional shape is more preferred from the viewpoint of efficiently obtaining bonding points between the fibers and firmly bonding the fibers together by thermal bonding.

[0058] In this process, the thermoplastic resin spun as described above is drawn under suction to obtain a continuous fiber. Alternatively, the high-melting point polymer and the low-melting point polymer spun as described above are further drawn under suction to obtain a continuous fiber in which the high-melting point polymer is not exposed but is instead covered by the low-melting point polymer. This suction drawing is generally performed by drawing with air using an ejector.

[0059] Here, the spinning speed during suction drawing is preferably 3000 m / min or more and 6000 m / min or less. By setting the spinning speed to preferably 3000 m / min or more, more preferably 3500 m / min or more, and even more preferably 4000 m / min or more, the fibers constituting the resulting fiber web can be more highly oriented and crystallized, so that the fibers do not shrink and wrinkle during preheating or heat bonding in subsequent processes, or the thermoplastic resin, particularly the low-melting-point polymer, does not fuse to heated rolls or the like, thereby reducing productivity. On the other hand, by setting the spinning speed during suction drawing to preferably 6000 m / min or less, more preferably 5500 m / min or less, and even more preferably 5000 m / min or less, excessive fiber orientation and crystallization can be suppressed, and heat bonding properties that contribute to improving the mechanical strength of the spunbonded nonwoven fabric can be obtained.

[0060] (b) Obtaining a nonwoven web In this step, the long fibers are caused to align with a dispersion plate having an average tilt angle θ of 0° or more and 40° or less, and then the long fibers are collected on a moving net conveyor to obtain a fiber web.

[0061] First, the dispersion plate is provided directly below the ejector 21 used during suction drawing, as illustrated in Fig. 2, and the dispersion plate 22 is provided at an average inclination angle θ, which will be described later, with respect to a normal line 24 from the ground surface 23. Here, this average inclination angle θ is θ = 0° when it is parallel to the normal line 24 from the ground surface 23, and as shown in Fig. 2, the angle in the opposite direction to the conveying direction of the fiber web (the direction indicated by arrow 25) is positive (θ > 0°).

[0062] The average inclination angle θ is preferably 0° or more and 40° or less. By setting the average inclination angle θ to preferably 0° or more, more preferably 1° or more, and even more preferably 2° or more, collisions between the long fibers at the bottom of the ejector can be avoided, and the resulting fiber web and spunbonded nonwoven fabric can be prevented from being partially twisted. On the other hand, by setting the average inclination angle θ to preferably 40° or less, more preferably 35° or less, and even more preferably 30° or less, uneven distribution of the long fibers at the bottom of the ejector can be suppressed, and the resulting fiber web and spunbonded nonwoven fabric can be prevented from having localized areas where long fibers are absent.

[0063] In this process, the long fibers are collected on a moving net conveyor to obtain a fiber web. In the present invention, "collecting the long fibers on a moving net conveyor" refers to sequentially depositing the long fibers on a rotating net conveyor, and the net conveyor refers to a belt conveyor in which the belt portion is a punched plate, a mesh, or a porous body. However, it is preferable to appropriately set the size of the holes, etc., taking into account the resin constituting the long fibers and the fiber diameter of the long fibers, so that the collected long fibers do not fall into the net conveyor through the perforations of the mesh, or through the holes of the punched plate or porous body (hereinafter abbreviated as "holes, etc."). The belt portion may be made of metal or synthetic resin.

[0064] (c) Obtaining a preheated fiber web In this step, only one surface of the fiber web is brought into contact with a heating surface to preheat the fiber web, thereby obtaining a preheated fiber web.

[0065] In this case, it is preferable that the temperature of the heating surface is 30°C to 110°C lower than the melting point of the thermoplastic resin (or low-melting point polymer), and the linear pressure of the heating surface is 1 N / cm to 100 N / cm. By satisfying these two conditions, the conveyability during production of the spunbond nonwoven fabric is improved, and a spunbond nonwoven fabric with good thermal insulation properties can be obtained.

[0066] First, it is preferable that the temperature of the heating surface is 30°C or more and 110°C or less lower than the melting point of the thermoplastic resin (or low-melting point polymer). When the temperature of the heating surface is 30°C or more lower than the melting point of the thermoplastic resin (or low-melting point polymer), excessive compression of the fiber web is suppressed, and a spunbonded nonwoven fabric with excellent thermal insulation properties can be obtained. On the other hand, when the temperature of the heating surface is 110°C or less lower than the melting point of the thermoplastic resin (or low-melting point polymer), the fiber web is appropriately preheated and crystallization of the resin that constitutes the fibers is promoted, thereby preventing the fiber web from becoming excessively densified in the thermal bonding step described below, and resulting in a spunbonded nonwoven fabric with excellent thermal insulation properties.

[0067] Next, the linear pressure of the heating surface is preferably 1 N / cm or more and 100 N / cm or less. By setting the linear pressure of the heating surface to 1 N / cm or more, the heating surface is uniformly abutted against the fiber web in the width direction, improving the transportability during production of the spunbonded nonwoven fabric. On the other hand, by setting the linear pressure of the heating surface to 100 N / cm or less, excessive compression of the fiber web is suppressed, and a spunbonded nonwoven fabric with good thermal insulation properties can be obtained.

[0068] (d) heat-bonding the preheated fiber web In this step, the preheated fiber web is thermally bonded by a pair of flat rolls.

[0069] In this case, it is preferable that the surface temperature of the pair of flat rolls is 30°C to 70°C lower than the melting point of the thermoplastic resin (or low-melting point polymer), and the linear pressure of the pair of flat rolls is 100 N / cm to 900 N / cm. By satisfying these two conditions, the preheated fiber web can be sufficiently thermally bonded, and a spunbonded nonwoven fabric having the desired smooth arithmetic mean roughness can be obtained.

[0070] First, the temperature of the heating surface is preferably 30°C to 110°C lower than the melting point of the thermoplastic resin (or low-melting point polymer). By lowering the temperature by 30°C or more ([melting point - 30]°C or less) and preferably by 40°C or more ([melting point - 40]°C or less) than the melting point of the thermoplastic resin (or low-melting point polymer), the surface temperature of the pair of flat rolls is not too high, preventing the preheated fiber web from wrapping around the flat rolls, and the web can be transported to a subsequent process. By lowering the temperature by 70°C or more ([melting point - 70]°C or more) and preferably by 60°C or more ([melting point - 60]°C or more) than the melting point, the preheated fiber web is sufficiently thermally bonded, resulting in a spunbond nonwoven fabric with sufficient mechanical strength.

[0071] Next, the linear pressure of the heating surface is preferably 100 N / cm or more and 900 N / cm or less. By setting the lower limit of this linear pressure range to 100 N / cm or more, preferably 500 N / cm or more, the preheated fiber web can be sufficiently thermally bonded to obtain a long-fiber nonwoven fabric having the desired arithmetic mean roughness. On the other hand, by setting the upper limit of this range to 900 N / cm or less, preferably 800 N / cm or less, the spunbonded nonwoven fabric can be prevented from partially forming a film without being strongly thermally bonded.

[0072] (e) Other post-processing processes However, in the method for producing the spunbond nonwoven fabric of the present invention, it is preferable to further carry out various post-processing steps, as in the case of general spunbond nonwoven fabrics. Of course, in the present invention, the spunbond nonwoven fabric obtained by carrying out these post-processing steps is also considered to be the spunbond nonwoven fabric of the present invention.

[0073] Examples of post-processing processes include processes that improve the electrical conductivity, flame retardancy, water and oil repellency, and antibacterial and antiviral properties of spunbond nonwoven fabrics.

[0074] [Laminate] In view of the above-mentioned properties, one preferred embodiment of the spunbonded nonwoven fabric according to the present invention is a laminate formed by laminating the spunbonded nonwoven fabric and a film via an adhesive resin. This embodiment results in a laminate that maintains heat retention while suppressing fiber shedding and is easy to tear by hand.

[0075] The materials constituting the film and adhesive resin are not particularly limited as long as they provide the necessary heat insulating properties and adhesiveness. However, examples of thermoplastic resins for the film include polyester-based resins, polyolefin-based resins, polystyrene-based resins, and polyvinyl chloride-based resins. Examples of adhesive resins include vinyl acetate resins, acrylic ester resins, ethylene-vinyl acetate copolymers, vinyl acetate-acrylic copolymers, polyamide-based resins, polyester-based resins, polyurethane-based resins, and epoxy-based resins. In particular, when the thermoplastic resin (high-melting point polymer, low-melting point polymer) of the spunbond nonwoven fabric, the thermoplastic resin of the film, and the adhesive resin are all the same thermoplastic resin, the adhesion to the spunbond nonwoven fabric is improved, resulting in a laminate that is also excellent in recyclability of used labels.

[0076] This laminate can be used for beverage containers such as PET bottles, and the beverage containers having the laminate coated on the surface, i.e., the laminate used as a label, can provide a beverage container that has heat insulation properties and print visibility while allowing easy label removal. It can also be used as a packaging bag for food, an outer packaging material for ice packs, etc. [Example]

[0077] Next, the spunbond nonwoven fabric of the present invention will be specifically described based on examples, although the present invention is not limited to these examples.

[0078] [Measurement method] The evaluation methods and measurement conditions used in the examples are explained below. Unless otherwise specified, the measurements of each physical property were carried out according to the above-mentioned methods.

[0079] (1) Melting point of thermoplastic resin (℃) Measurement was carried out using a differential scanning calorimeter "DSC-2" manufactured by PerkinElmer Co., Ltd., at a temperature rise rate of 20°C / min, and the temperature at which the extreme value was obtained in the obtained melting endothermic curve was taken as the melting point.

[0080] (2) Intrinsic viscosity (IV) of thermoplastic resin The intrinsic viscosity (IV) of the thermoplastic resin was measured by the following method.

[0081] Dissolve 8 g of sample in 100 mL of orthochlorophenol, and measure the relative viscosity η using an Ostwald viscometer at 25°C. r was calculated by the following formula:

[0082] η r =η / η0=(t×d) / (t0×d0) (formula) (where η is the viscosity of the polymer solution, η0 is the viscosity of orthochlorophenol, t is the solution drop time (seconds), and d is the solution density (g / cm 3 ), t0 is the fall time of orthochlorophenol (seconds), and d0 is the density of orthochlorophenol (g / cm 3 ) respectively. Next, the relative viscosity η r The intrinsic viscosity (IV) was calculated using the following formula: Intrinsic viscosity (IV)=0.0242η r +0.2634...(expression).

[0083] (3) Average single fiber diameter (μm) The average single fiber diameter of the fibers was measured and calculated by the above-mentioned method using a scanning electron microscope "VHX-D500" manufactured by Keyence Corporation.

[0084] (4) Arithmetic mean roughness Ra (μm) of spunbond nonwoven fabric The arithmetic mean roughness Ra of the spunbond nonwoven fabric was measured and calculated by the above-mentioned method.

[0085] (5) Fiber orientation distribution (%) of spunbond nonwoven fabric The degree of fiber orientation of the spunbonded nonwoven fabric was measured and calculated by the above-mentioned method.

[0086] (6) Basis weight of spunbond nonwoven fabric (g / m 2 ) The basis weight of the spunbond nonwoven fabric was measured and calculated by the method described above.

[0087] (7) Thickness of spunbond nonwoven fabric (mm) The thickness of the spunbond nonwoven fabric was measured and calculated using a thickness meter "Teclock" (registered trademark) SM-114 manufactured by Teclock Corporation, according to the method described above.

[0088] (8) Apparent density of spunbond nonwoven fabric (g / cm 3 ) The apparent density of the spunbond nonwoven fabric was measured and calculated by the method described above.

[0089] (9) Q-max (W / cm) of spunbond nonwoven fabric 2 ) The Q-max of the spunbond nonwoven fabric was measured and calculated by the above-mentioned method.

[0090] (10) Anti-transparency index of spunbond nonwoven fabric The print visibility of the spunbond nonwoven fabric was evaluated by evaluating its anti-see-through index. The anti-see-through index of this spunbond nonwoven fabric was measured in accordance with "8.2 B Method (Instrument Method)" of JIS L1923:2017 "Method for evaluating the anti-see-through properties of textile products" using a Shimadzu UV-1280 ultraviolet-visible spectrophotometer (Type 1 spectrophotometer) with visible light at a measurement wavelength of 380 nm to 780 nm, and the anti-see-through index was calculated.

[0091] (11) Thermal insulation properties of spunbond nonwoven fabrics The heat insulating properties of the spunbond nonwoven fabric were evaluated as follows. An empty 275 mL aluminum bottle with a heat-shrunk label was filled with hot water at 60°C and left for 10 seconds in an atmosphere at 23°C. The surface temperature of the bottle body was then measured with a thermoelectric thermometer. After leaving the bottle for 10 seconds, the bottle body was also touched with a hand and the degree of heat was evaluated according to the following evaluation criteria: <Evaluation criteria> The bottle body does not feel warm to the touch, and feels as if it contains water at the same temperature as the ambient air: A The bottle body is only slightly warm to the touch, and the container can be easily touched: B The bottle body feels warm to the touch, and continuing to touch the container is not painful: C The bottle body feels a little hot when touched, making it difficult to keep touching the container. The bottle body feels hot to the touch and it is difficult to touch the container: E.

[0092] (12) Tear strength per unit area of ​​spunbond nonwoven fabric (N / (g / m 2 )) The tear strength per unit area was evaluated to evaluate the hand tearability of the spunbonded nonwoven fabric. That is, the tear strength per unit area of ​​the spunbonded nonwoven fabric was measured using a constant-speed extension tensile tester (for example, Baldwin's "RTG-1250") in accordance with JIS L1913:2010 "Test methods for general nonwoven fabrics," section 6.4 "Tear strength," a) trapezoid method, as follows: (i) Three samples measuring 25 cm x 5.0 cm in width are taken from the nonwoven fabric at equal intervals in the MD direction. (ii) Mark the test piece with an isosceles trapezoidal shape and make a 1.0 cm cut at right angles to the short side at the centre of the short side of this mark. (iii) The test piece is attached to the grips along the marks in a constant-rate extension tensile testing machine with a gripping distance of 10 cm, with the short sides of the trapezoid tensile and the long sides loose. (iv) The maximum load when torn at a tensile speed of 100±10 mm / min is taken as the tear strength (N), and the average value of three points is calculated to be the tear strength (N) of the spunbond nonwoven fabric. (v) The tear strength (N / (g / m) per unit area of ​​the spunbond nonwoven fabric based on the following formula: 2 )) and round to the nearest tenth. Tear strength per unit area of ​​spunbond nonwoven fabric (N / (g / m 2 )) = [Tear strength of spunbond nonwoven fabric (N)] / basis weight (g / m 2 )...(expression).

[0093] [Resin used] Next, the resins used in the examples and comparative examples will be described in detail. Polyester resin A: Polyethylene terephthalate (referred to as PET in Tables 1 and 2) dried to a moisture content of 50 mass ppm or less, with an intrinsic viscosity (IV) of 0.65 and a melting point of 260°C. Polyester resin B: Copolymerized polyethylene terephthalate (referred to as Co-PET in Tables 1 and 2) dried to a moisture content of 50 mass ppm or less, with an intrinsic viscosity (IV) of 0.64, an isophthalic acid copolymerization rate of 11 mol%, and a melting point of 230°C.

[0094] [Example 1] (Process for obtaining long fibers) The PET was melted as the high-melting point polymer at 295° C., and the Co-PET was melted as the low-melting point polymer at 280° C. Then, the high-melting point polymer was used as the core component and the low-melting point polymer was used as the sheath component, and the mixture was melt-extruded from the round nozzle of the bicomponent spinneret at a spinneret temperature of 295° C. and a content ratio of the high-melting point polymer (core component) to the low-melting point polymer (sheath component) of core component:sheath component = 80:20.

[0095] The high melting point polymer and low melting point polymer thus melt-extruded from the composite spinneret were then suction-drawn using an ejector at a spinning speed of 4900 m / min to obtain continuous fibers that were concentric core-sheath composite fibers.

[0096] (Step of obtaining a fiber web) Next, the obtained long fibers are allowed to run along a dispersion plate having an average inclination angle θ of 20°, and then the long fibers are collected on a moving net conveyor having a belt portion made of a synthetic resin net. The long fibers are then collected and spun into a concentric core-sheath composite fiber having an average single fiber diameter of 12.3 μm and a circular cross section, and the fiber weight is 20 g / m. 2 A fiber web of

[0097] (Step of obtaining preheated fiber web) The fiber web obtained in the previous step was further transported on the net conveyor, and only the surface of this fiber web that was not in contact with the net conveyor was preheated by contacting a heating plate (made of metal, heating surface temperature: 155°C) installed above the net conveyor with a linear pressure of 50 N / cm, thereby preheating only one surface of the fiber web and obtaining a preheated fiber web.

[0098] (Thermal bonding process) The preheated fiber web was thermally bonded by passing it through a calender consisting of a pair of metal flat rolls (thermal bonding rate: 100%), both of which had a surface temperature of 185°C and a linear pressure of 500 N / cm, to obtain a spunbonded nonwoven fabric. The physical properties of the obtained spunbonded nonwoven fabric are shown in Table 1.

[0099] [Example 2] In the step of obtaining a fiber web, except that the average inclination angle θ of the spreader plate was changed to 10°, a spunbonded nonwoven fabric was obtained under the same conditions as in Example 1. The physical properties of the obtained spunbonded nonwoven fabric are shown in Table 1.

[0100] [Example 3] A spunbonded nonwoven fabric was obtained under the same conditions as in Example 1, except that in the thermal bonding step, the surface temperature of the flat roll was changed to 190°C and the linear pressure was changed to 700 N / cm. The physical properties of the obtained spunbonded nonwoven fabric are shown in Table 1.

[0101] [Example 4] A spunbonded nonwoven fabric was obtained under the same conditions as in Example 1, except that in the step of obtaining continuous fibers, both the high-melting point polymer (core component) and the low-melting point polymer (sheath component) were changed to PET. The physical properties of the obtained spunbonded nonwoven fabric are shown in Table 1.

[0102] [Example 5] A spunbonded nonwoven fabric was obtained under the same conditions as in Example 4, except that in the thermal bonding step, the surface temperature of the flat roll was changed to 250° C. The physical properties of the obtained spunbonded nonwoven fabric are shown in Table 1.

[0103] [Example 6] In the process of obtaining long fibers, the resin extrusion rate was adjusted so that the average single fiber diameter was 18.0 μm, and the weight per unit area was 20 g / m 2 A spunbonded nonwoven fabric was obtained under the same conditions as in Example 1, except that the speed of the net conveyor was adjusted so that the spunbonded nonwoven fabric obtained satisfies the following criteria: The physical properties of the obtained spunbonded nonwoven fabric are shown in Table 2.

[0104] [Example 7] In the step of obtaining a fiber web, the basis weight of the obtained nonwoven fabric is 20 g / m 2 It was originally adjusted to 30g / m 2 A spunbonded nonwoven fabric was obtained under the same conditions as in Example 1, except that the thickness was adjusted so that the following was true: Table 2 shows the physical properties of the obtained spunbonded nonwoven fabric.

[0105] [Comparative Example 1] In (the step of obtaining a fiber web), the physical properties of the obtained spunbond nonwoven fabric are shown in Table 2, except that the average inclination angle θ of the spreader plate was changed to 0°.

[0106] Comparative Example 2 A spunbonded nonwoven fabric was obtained under the same conditions as in Example 1, except that the roll configuration was changed to the following in (the step of fusing the nonwoven web). Upper roll: Metal embossing roll with a surface temperature of 185°C Bottom roll: Metal flat roll with a surface temperature of 185°C -Linear pressure of metal roll: 686N / cm. The physical properties of the obtained spunbond nonwoven fabric are shown in Table 2.

[0107] [Table 1]

[0108] [Table 2]

[0109] The properties of the obtained nonwoven fabrics are as shown in Tables 1 and 2. The spunbond nonwoven fabrics of Examples 1 to 7 had sufficient heat insulation, good print visibility, and excellent hand-tearability. In particular, Example 1 had good heat insulation and print visibility, and was easy to hand-tear, making it a spunbond nonwoven fabric suitable for use as a skin material.

[0110] On the other hand, the spunbond nonwoven fabrics of Comparative Examples 1 and 2 did not have good visibility or good hand-tearability. [Explanation of symbols]

[0111] 11: Fiber 12: Measurement range frame 13:0 degree reference line 14: MD direction arrow 15: CD direction arrow 21: Ejector 22: Dispersion plate 23: Ground 24: Normal from the ground 25: Arrow indicating the direction of fiber web transport 26: Moving net conveyor θ 11 ~θ 14 : Fiber orientation angle relative to the 0 degree reference line θ: average tilt angle

Claims

1. A spunbond nonwoven fabric made of fibers containing a thermoplastic resin as a main component, wherein at least one arithmetic mean roughness Ra is 4.0 μm or more and 10.0 μm or less, and the proportion of fibers having a fiber orientation degree of 0° or more and 20° or less is 40% or more and 70% or less.

2. Q-max is 0.01 W / cm ２ 0.10W / cm or more ２ 2. The spunbond nonwoven fabric of claim 1, wherein:

3. 3. The spunbond nonwoven fabric according to claim 1, wherein the fibers are conjugated fibers in which a low-melting polymer having a melting point lower than that of a high-melting polymer is disposed around the high-melting polymer.

4. 3. The spunbond nonwoven fabric according to claim 1, wherein the average single fiber diameter of the fibers is 5.0 μm or more and 16.0 μm or less.

5. Weight per unit area is 5g / m 2 50g / m or more 2 3. The spunbond nonwoven fabric of claim 1, wherein:

6. A laminate comprising the spunbond nonwoven fabric according to claim 1 or 2 and a film laminated together via an adhesive resin.

7. a step of spinning a thermoplastic resin through an outlet hole of a spinneret and further drawing the resin by suction to obtain a long fiber; a step of causing the long fibers to align with a dispersion plate having an average inclination angle θ of 0° or more and 40° or less, and then collecting the long fibers on a moving net conveyor to obtain a fiber web; a step of preheating only one surface of the fiber web by bringing a heating surface into contact with the fiber web to obtain a preheated fiber web; a step of thermally bonding the preheated fiber web with a pair of flat rolls; The method for producing the spunbonded nonwoven fabric, the spinning speed during the suction drawing is 3000 m / min or more and 6000 m / min or less, In the preheating, the temperature of the heating surface is lower than the melting point of the thermoplastic resin by 30°C or more and 110°C or less, and the linear pressure of the heating surface is 1 N / cm or more and 100 N / cm or less, In the thermal bonding, the surface temperature of the pair of flat rolls is 30°C to 70°C lower than the melting point of the thermoplastic resin, and the linear pressure of the pair of flat rolls is 100 N / cm to 900 N / cm.

8. a step of spinning a high-melting-point polymer and a low-melting-point polymer having a melting point 10°C to 110°C lower than the melting point of the high-melting-point polymer through an outlet hole of a composite spinneret, and further drawing the resulting fibers under suction to obtain long fibers in which the high-melting-point polymer is covered with the low-melting-point polymer without exposing the high-melting-point polymer; a step of causing the long fibers to align with a dispersion plate having an average inclination angle θ of 0° or more and 40° or less, and then collecting the long fibers on a moving net conveyor to obtain a fiber web; a step of preheating only one surface of the fiber web by bringing a heating surface into contact with the fiber web to obtain a preheated fiber web; a step of thermally bonding the preheated fiber web with a pair of flat rolls; The method for producing the spunbonded nonwoven fabric, the spinning speed during the suction drawing is 3000 m / min or more and 6000 m / min or less, In the preheating, the temperature of the heating surface is lower than the melting point of the low-melting point polymer by 30°C or more and 110°C or less, and the linear pressure of the heating surface is 1 N / cm or more and 100 N / cm or less, In the thermal bonding, the surface temperature of the pair of flat rolls is 30°C to 70°C lower than the melting point of the low-melting point polymer, and the linear pressure of the pair of flat rolls is 100 N / cm to 900 N / cm.

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