JPWO2019146660A1 - Spun bond non-woven fabric - Google Patents

Abstract

The non-woven fabric of the present invention is a spunbonded non-woven fabric composed of a single component fiber made of a copolymerized polyester-based resin obtained by copolymerizing 5% by weight or more and 40% by weight or less of polyethylene glycol with a polyester-based resin. A spunbonded nonwoven fabric having a ΔMR of 0.5% or more and 15% or less.

Description

The present invention relates to a spunbonded nonwoven fabric that is flexible and has excellent tactile sensation.

In general, non-woven fabrics for protective materials such as disposable diapers and sanitary napkins are required to have excellent texture and flexibility because they are soft to the touch when worn.

Long-fiber non-woven fabrics such as spunbonded non-woven fabrics are used in various applications because of their strength, breathability, flexibility and other characteristics and high productivity. While various resins such as polyester-based and polyolefin-based resins are used as the raw materials, the use of copolymerized polyester-based resins for spunbonded non-woven fabrics has been considered.

For example, a non-woven fabric composed of fibers containing a thermoplastic water-absorbent resin copolymerized with polyalkylene glycol has been proposed (see Patent Document 1).

Further, a non-woven fabric composed of a core-sheath fiber containing a copolymerized polyester resin of polyalkylene glycol and aromatic polyester as a sheath component and a polyester resin as a core component has been proposed (see Patent Document 2).

Japanese Patent Application Laid-Open No. 2006-299424 Japanese Patent Application Laid-Open No. 2003-336156

However, in the technique disclosed in Patent Document 1, when a resin obtained by copolymerizing 45% by mass of polyethylene glycol with polytetramethylene terephthalate is used as the copolymerized polyester resin as exemplified in the specification, the resin is used. Since the fiber containing the above has too high water absorption, it has a problem that it has a sticky feel when it is made into a non-woven fabric and the texture is inferior.

Further, in the technique disclosed in Patent Document 2, since the technique uses a rigid polyester resin for the core portion, there is a problem that the bending rigidity of the fiber is high and the flexibility when made into a spunbonded non-woven fabric is inferior. ..

Therefore, an object of the present invention is to provide a spunbonded nonwoven fabric having flexibility and excellent tactile sensation in view of the above problems.

As a result of diligent studies to achieve the above object, the present inventors have found that a copolymerized polyester resin obtained by copolymerizing a specific amount of polyethylene glycol can greatly improve flexibility and tactile sensation. It was.

The present invention has been completed based on these findings, and the following inventions are provided according to the present invention.

The spunbonded non-woven fabric of the present invention is a spunbonded nonwoven fabric composed of a single component fiber made of a copolymerized polyester-based resin obtained by copolymerizing 5% by weight or more and 40% by weight or less of polyethylene glycol with a polyester-based resin. The ΔMR of the non-woven fabric is 0.5% or more and 15% or less.
According to a preferred embodiment of the present invention, the polyester resin is polyethylene terephthalate.

According to the present invention, it is possible to further improve the flexibility and obtain a spunbonded nonwoven fabric having less stickiness, smoothness and excellent tactile sensation. Further, since the strength of the fiber is increased, the sheet processability is excellent and the productivity can be improved.

The non-woven fabric of the present invention is a spunbonded non-woven fabric composed of a single component fiber made of a copolymerized polyester-based resin obtained by copolymerizing 5% by weight or more and 40% by weight or less of polyethylene glycol with a polyester-based resin. A spunbonded nonwoven fabric having a ΔMR of 0.5% or more and 15% or less.

Examples of the polyester-based resin used in the present invention include polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, and polylactic acid, and polyethylene terephthalate is particularly preferable. By using polyethylene terephthalate, the fiber has excellent flexibility and tactile sensation, and can be drawn at a high spinning speed, so that the fiber can be easily oriented and crystallized and has mechanical strength.

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

The copolymerization amount of the polyethylene glycol contained in the copolymerized polyester resin used in the present invention is 5% by weight or more and 40% by weight or less. By setting the copolymerization amount of polyethylene glycol to 5% by weight or more, more preferably 7% by weight or more, a non-woven fabric having excellent flexibility and tactile sensation can be obtained. Further, by setting the copolymerization amount of polyethylene glycol to 40% by weight or less, more preferably 20% by weight or less, it is possible to obtain a fiber having heat resistance and high mechanical strength that can withstand practical use. The copolymerization amount of polyethylene glycol contained in the copolymerized polyester resin in the present invention refers to a value measured by the method described in Examples.

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

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

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

In the esterification method, terephthalic acid and ethylene glycol are charged in a reaction vessel and an esterification reaction is carried out at 150 ° C. or higher and 270 ° C. or lower under nitrogen pressurization. After the esterification reaction is completed, a stabilizer, a polycondensation catalyst, etc. are added to 500 Pa or less. It can be obtained by heating under a reduced pressure of 250 ° C. or higher and 300 ° C. or lower and reacting for 3 hours or more and 5 hours or less.

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

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

It is important that the ΔMR of the spunbonded nonwoven fabric of the present invention is 0.5% or more and 15% or less. As a result of diligent studies, the present inventors have found that there is a high correlation between ΔMR, which is a parameter conventionally used as an index of moisture absorption and desorption of fibers, and the tactile sensation of spunbonded non-woven fabric. By setting ΔMR to 0.5% or more, more preferably 2% or more, the surface of the spunbonded non-woven fabric is in a state of appropriately absorbing moisture, and a good tactile sensation with a moist feeling when touching the surface is obtained. On the other hand, when ΔMR is set to 15% or less, more preferably 10% or less, still more preferably 7% or less, a non-sticky feel is obtained. Further, when ΔMR is within the above range, the spunbonded nonwoven fabric can have slipperiness and flexibility suitable for high-speed production of the spunbonded nonwoven fabric, and has excellent high-order processability.

ΔMR can be adjusted by the type of polyester component, the number average molecular weight of the polyethylene glycol contained, and the amount of copolymerization.

ΔMR in the present invention refers to a value measured and calculated by the following method.
(1) 3 g of the measurement sample is freeze-milled, vacuum-dried at a drying temperature of 110 ° C. for 24 hours, and its absolute dry mass (W _d ) is measured.
(2) The above sample was subjected to 20 ° C. × 65% R. H. The sample is left in a constant temperature and humidity chamber adjusted to the above state for 24 hours, and the mass (W ₂₀ ) of the sample in an equilibrium state is measured.
(3) Next, the setting of the constant temperature and humidity chamber was changed to 30 ° C. × 90% R. H. The mass (W ₃₀ ) is measured after being left for 24 hours, and calculated based on the following formula.
-ΔMR = (W _30- W ₂₀ ) / W _d (%).

It is important that the copolymerized polyester fiber constituting the spunbonded nonwoven fabric of the present invention is a single component fiber. Since the fiber is a single component fiber, the flexibility of the copolymerized polyester resin is reflected, so that the spunbonded non-woven fabric has a soft tactile sensation. Further, since the spinnability is improved as compared with the composite fiber, the spunbonded non-woven fabric has few defects.

The average single fiber diameter of the copolymerized polyester fibers constituting the spunbonded nonwoven fabric of the present invention is preferably 10 μm or more and 16 μm or less. By setting the average single fiber diameter to 10 μm or more, more preferably 11 μm or more, the workability at the time of post-processing can be improved and the number of defects can be reduced. On the other hand, by setting the average single fiber diameter to 16 μm or less, more preferably 15 μm or less, the tactile sensation when touching the surface of the spunbonded nonwoven fabric obtained from the copolymerized polyester fiber becomes smooth. In addition, the flexibility is further improved by the decrease in the moment of inertia of area due to the small average single fiber diameter. On the other hand, when the average single fiber diameter is less than 10 μm, the workability at the time of post-processing is lowered, so that the number of defects increases. The average single fiber diameter of the copolymerized polyester fiber in the present invention is defined as the average single fiber diameter of the copolymerized polyester fiber, which is towed by an ejector, stretched, and then 10 small pieces are randomly collected from a non-woven web collected on a net, and 500 to 500 to 500 with a microscope. A 1000-fold surface photograph is taken, the width of a total of 100 fibers is measured from each sample, 10 fibers, and the value (μm) calculated from the arithmetic mean value is used.

The spunbonded nonwoven fabric of the present invention preferably has a bend-back property of 0.2 cm ^-1 or more and 1.0 cm ^-1 or less. When the bending back property is 1.0 cm ^-1 or less, a feeling that fits the hand at the time of bending back is obtained, and when it is 0.2 cm ^-1 or more, an appropriate return difficulty is obtained and a natural texture is obtained. Because it becomes. This bending back property is more preferably 0.8 cm ^-1 or less, and further preferably 0.6 cm ^-1 or less. Further, 0.3 cm ^-1 or more is more preferable, and 0.4 cm ^-1 or more is more preferable.

Bending back property can be controlled by the above-mentioned thermoplastic resin, additives, fiber diameter, and / or the spinning speed, basis weight, apparent density, and bonding method described later.

The bending return property of the spunbonded non-woven fabric in the present invention means that the bending rigidity (B) and the bending hysteresis (2HB) in two orthogonal directions are determined by a bending tester (for example, "KES-FB2", manufactured by Kato Tech Co., Ltd.). It is a value measured and obtained by the following formula.
-Flexural rigidity = (B in direction 1 + B in direction 2) / 2
Bending hysteresis = (2HB in direction 1 + 2HB in direction 2) / 2
・ Bending return = bending hysteresis / bending rigidity

Spunbonded nonwoven fabric of the present invention preferably has a bending stiffness is less than 10μN · ^cm 2 / ^cm or more 300μN · ^cm 2 / ^cm. By bending stiffness is less than 300μN · ^cm 2 / ^cm, pliable soft feeling is obtained, by at 10μN · ^cm 2 / ^cm or more, in order to moderate the bending response is obtained. The flexural rigidity, more preferably not more than 250μN · ^cm 2 / ^cm, more preferably not more than 200μN · ^cm 2 / ^cm. Further, 20 μN · cm ² / cm or more is more preferable, and 30 μN · cm ² / cm or more is further preferable. Flexural rigidity can be controlled by the above-mentioned thermoplastic resin, additives, fiber diameter, and / or the spinning speed, basis weight, apparent density, and bonding method described later.

The flexural rigidity of the spunbonded non-woven fabric referred to in the present invention is defined by measuring the flexural rigidity (B) in two orthogonal directions with a bending tester (for example, "KES-FB2", manufactured by Kato Tech Co., Ltd.) and using the following formula. It is a value obtained by.
-Flexural rigidity = (B in direction 1 + B in direction 2) / 2

The spunbonded nonwoven fabric of the present invention preferably has a tensile elastic modulus of 5 MPa or more and 100 MPa or less. This is because when the tensile elastic modulus is 100 MPa or less, deformation is facilitated, so that a feeling of following the hand can be obtained, and when it is 5 MPa or more, an appropriate resistance feeling can be obtained. The tensile elastic modulus is more preferably 80 MPa or less, and even more preferably 60 MPa or less. Further, 7 MPa or more is more preferable, and 9 MPa or more is even more preferable. The tensile modulus can be controlled by the thermoplastic resin, the additive, the fiber diameter, and / or the spinning speed, the texture, the apparent density, and the bonding method described later.

The tensile elastic modulus of the spunbonded non-woven fabric referred to in the present invention is defined as "6.3.1 Standard time" of "6.3 Tensile strength and elongation (ISO method)" of JIS L1913: 2010 "General non-woven test method". According to a tensile test with a gripping interval of at least 5 cm, which is carried out in accordance with the same procedure, it is an arithmetic average of the tensile elastic moduli in two orthogonal directions. For this tensile elastic modulus, the curve (stress-strain curve) obtained by the load and the elongation rate is obtained, and the largest slope (the increase in the load is large with respect to the elongation rate) is obtained in the region where the elongation rate is 20% or less. The value divided by the area. The cross-sectional area of the present invention is the product of the sample width and the thickness (T ₀ ) under a load of 0.5 g / cm ² measured by a compression tester (for example, "KES-FB3", manufactured by Kato Tech Co., Ltd.). is there.

The spunbonded non-woven fabric of the present invention has a tensile strength per unit grain of 0.3 (N / 5 cm) / (g / m ² ) or more and 10 (N / 5 cm) / (g / m ² ) or less. preferable. When the tensile strength per unit grain is 0.3 (N / 5 cm) / (g / m ² ) or more, it can withstand the process passability when manufacturing paper diapers and the like and can be used as a product. This is because flexibility can be combined by having 10 (N / 5 cm) / (g / m ² ) or less. The tensile strength per unit basis weight is more preferably 8 (N / 5 cm) / (g / m ² ) or less, and further preferably 6 (N / 5 cm) / (g / m ² ) or less. Further, 0.4 (N / 5 cm) / (g / m ² ) or more is more preferable, and 0.5 (N / 5 cm) / (g / m ² ) or more is further preferable. The tensile strength per unit basis weight can be controlled by the above-mentioned thermoplastic resin, additives, fiber diameter, and / or the spinning speed, basis weight, apparent density, and bonding method described later.

The tensile strength of the spunbonded non-woven fabric referred to in the present invention is in accordance with "6.3.1 Standard time" of "6.3 Tensile strength and elongation (ISO method)" of JIS L1913: 2010 "General non-woven test method". It is a value obtained by dividing the average of the tensile strengths (strengths when the sample is broken) in two orthogonal directions by a scale in a tensile test carried out with a gripping interval of at least 5 cm.

The rigidity of the spunbonded nonwoven fabric of the present invention is preferably 70 mm or less. By setting the rigidity to be preferably 70 mm or less, more preferably 67 mm or less, still more preferably 64 mm or less, sufficient flexibility can be obtained particularly when used as a non-woven fabric for sanitary materials. Further, the lower limit of the rigidity is preferably 10 mm or more because if the rigidity is too low, the handleability of the non-woven fabric may be inferior. Rigidity and softness can be adjusted by resin, basis weight, average single fiber diameter and embossed roll (compression rate, temperature and linear pressure). The rigidity and softness in the present invention are calculated in accordance with JIS L1913: 2010 "General non-woven fabric test method", "6.7 Rigidity and softness", "6.7.3 41.5 ° cantilever method". As a calculation method, first, five test pieces having a width of 25 mm × 150 mm are collected, and the short sides of the test pieces are placed on a horizontal table having a slope of 45 ° so as to align with the scale baseline. Next, the test piece is manually slid in the direction of the slope, and when the center point of one end of the test piece comes into contact with the slope, the moving length of the position of the other end is read by a scale. The average value calculated by measuring the front and back of five test pieces is the rigidity in the present invention.

The basis weight of the spunbonded non-woven fabric of the present invention is preferably 5 g / m ² or more and 50 g / m ² or less, and more preferably 10 g / m ² or more and 30 g / m ² or less. When the basis weight is within the above range, the flexibility of the spunbonded non-woven fabric can be suitably exhibited. The grain in the present invention is based on "6.2 Mass per unit area" of JIS L1913: 2010 "General non-woven fabric test method", and three 20 cm x 25 cm test pieces are collected per 1 m of sample width and standard. weigh each mass (g) in the state, and it refers to a value represented the arithmetic mean value at 1 m ² per mass (g / m ^2).

The spunbonded nonwoven fabric of the present invention preferably has an apparent density of 0.01 g / cm ³ or more and 0.30 g / cm ³ or less. When it is 0.01 g / cm ³ or more, it is easy to obtain morphological stability that can be put to practical use, and it is easy to reduce the bending back rate, and when it is 0.30 g / cm ³ or less, it is easy to obtain breathability and flexibility. This is because it is easy to obtain. The apparent density is more preferably 0.25 g / cm ³ or less, and further preferably 0.20 g / cm ³ or less. Further, 0.03 g / cm ³ or more, more preferably, 0.05 g / cm ³ or more is more preferable.
The apparent density of the spunbonded nonwoven fabric in the present invention is a value obtained by dividing the basis weight by the thickness.

The spunbonded non-woven fabric of the present invention can be widely used for medical hygiene materials, daily life materials, industrial materials, etc., but has excellent flexibility, good tactile sensation, and few product defects, so that it has good workability. Therefore, it can be particularly preferably used as a sanitary material. Specifically, they are disposable diapers, sanitary napkins, and base cloths for poultices.

Next, the method for producing the spunbonded nonwoven fabric of the present invention will be described with reference to specific examples.
In the spunbond method for producing a spunbonded non-woven fabric, a resin is melted, spun from a spinneret, and then cooled and solidified. The resulting yarn is pulled by an ejector, stretched, and placed on a moving net. This is a manufacturing method that requires a process of collecting, forming a non-woven fiber web, and then heat-bonding.

As the shape of the spinneret and the ejector used, various shapes such as a round shape and a rectangular shape can be adopted. Among them, it is preferable to use a combination of a rectangular base and a rectangular ejector from the viewpoint that the amount of compressed air used is relatively small and the yarns are less likely to be fused or scratched.

In the present invention, the spinning temperature when the copolymerized polyester resin is vacuum-dried and then the copolymerized polyester resin is melted and spun is preferably 240 ° C. or higher and 320 ° C. or lower, more preferably 250 ° C. or higher and 310. It is ℃ or less, and more preferably 260 ℃ or more and 300 ℃ or less. By setting the spinning temperature within the above range, a stable molten state can be obtained and excellent spinning stability can be obtained.

The copolymerized polyester resin is melted and weighed in an extruder, supplied to a spinneret, and spun as long fibers.
The spun long fiber yarn is cooled next, and as a method of cooling the spun yarn, for example, a method of forcibly blowing cold air onto the yarn, an atmospheric temperature around the yarn, etc. A method of naturally cooling the yarn, a method of adjusting the distance between the spinneret and the ejector, and the like, or a method of combining these methods can be adopted. Further, the cooling conditions can be appropriately adjusted and adopted in consideration of the discharge amount per single hole of the spinneret, the spinning temperature, the atmospheric temperature and the like.

Next, the cooled and solidified yarn is towed and stretched by the compressed air injected from the ejector.
The spinning speed is preferably 2000 m / min or more, more preferably 3000 m / min or more, and even more preferably 4000 m / min or more. By setting the spinning speed to 2000 m / min or more, high productivity can be obtained, and the orientation and crystallization of the fibers can be advanced to obtain high-strength long fibers.

The spinning speed in the present invention was calculated from the above average single fiber diameter and the solid density of the resin used, with the mass per 10,000 m in length as the single fiber fineness and rounded to the second decimal place. Based on the single fiber fineness (dtex) and the discharge amount of resin discharged from the single hole of the spinneret (hereinafter abbreviated as single hole discharge amount) (g / min) set under each condition, based on the following formula. The spinning speed was calculated.
-Spinning speed = (10000 x single hole discharge amount) / single fiber fineness

Subsequently, the obtained long fibers are collected on a moving net to form a non-woven fiber web. In the present invention, since the fibers are drawn at a high spinning speed, the fibers ejected from the ejector are collected in the net in a state controlled by a high-speed air flow, so that a non-woven fabric with less fiber entanglement and high uniformity can be obtained. be able to.

Subsequently, the obtained non-woven fiber web is integrated by thermal adhesion to obtain the intended spunbonded non-woven fabric.

As a method of integrating the above non-woven fiber webs by heat bonding, a heat embossed roll in which a pair of upper and lower roll surfaces are engraved (concavo-convex parts), a roll having a flat (smooth) one roll surface and the other There are various methods of thermal bonding using various rolls such as a thermal embossing roll consisting of a roll with engraving (unevenness) on the surface of the roll and a thermal calendar roll consisting of a pair of upper and lower flat (smooth) rolls. Be done.

The embossed bonding area ratio at the time of heat bonding is preferably 5% or more and 30% or less. By setting the bonding area to preferably 5% or more, more preferably 10% or more, it is possible to obtain strength that can be put into practical use as a spunbonded non-woven fabric. On the other hand, by setting the adhesive area to preferably 30% or less, more preferably 20% or less, sufficient flexibility can be obtained particularly when used as a spunbonded non-woven fabric for sanitary materials.

The bonding area referred to here occupies the entire non-woven fabric of the portion where the convex portion of the upper roll and the convex portion of the lower roll overlap and come into contact with the non-woven fiber web when heat-bonding is performed by a roll having a pair of irregularities. Say the ratio. Further, in the case of thermal adhesion between a roll having irregularities and a flat roll, it means the ratio of the convex portion of the roll having irregularities to the entire non-woven fabric of the portion in contact with the non-woven fiber web.

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

The linear pressure of the heat embossing roll at the time of heat bonding is preferably 5 to 70 N / cm. By setting the linear pressure of the roll to preferably 5 N / cm or more, more preferably 10 N / cm or more, and further preferably 20 N / cm or more, sufficient heat adhesion can be obtained to obtain strength that can be put into practical use as a non-woven fabric. On the other hand, by setting the linear pressure of the roll to preferably 70 N / cm or less, more preferably 60 N / cm or less, still more preferably 50 N / cm or less, sufficient flexibility is provided especially when used as a non-woven fabric for sanitary materials. Obtainable.

Next, the present invention will be specifically described based on Examples. In addition, in the measurement of each physical property, if there is no particular description, the measurement is performed based on the above method. However, the present invention is not limited to these examples.
(1) Measurement of Number Average Molecular Weight and Copolymerization Amount of Polyethylene Glycol Contained in Copolymerized Polyester Resin Regarding the measurement of the number average molecular weight of polyethylene glycol, the GPC measuring device and conditions were as follows.
-Device: Gel permeation chromatography GPC
-Detector: Differential refractive index detector RI (RI-8020 manufactured by Tosoh, sensitivity 128x)
・ Photodiode array detector (SPD-M20A manufactured by Shimadzu Corporation)
-Column: TSKgelG3000PWXL (1) (Tosoh)
-Solvent: 0.1 M sodium chloride aqueous solution-Flow velocity: 0.8 mL / min
-Column temperature: 40 ° C
・ Injection volume: 0.05 mL
-Standard sample: polyethylene glycol, polyethylene oxide.
(2) ΔMR (%):
As a constant temperature and humidity constant device, "LHU-123" manufactured by ESPEC was used for the measurement.
(3) Thickness T ₀ (mm):
As a compression tester, "KES-FB3" manufactured by Katou Tech Co., Ltd. was used for the measurement.
(4) Flexural rigidity (μN · cm ² / cm), bending return (cm ^-1 ):
As a bending tester, "KES-FB2" manufactured by Katou Tech Co., Ltd. was used for the measurement.
(5) Tensile elastic modulus (MPa):
As a tensile tester, "AGS1KNX" manufactured by Shimadzu Corporation was used for measurement. The same apparatus as in (2) above was used for measuring the sample thickness T ₀ (mm).
(6) Apparent density (g / cm ³ ):
It was calculated by dividing the basis weight by the thickness T ₀ (mm). The same apparatus as in (2) above was used for measuring the sample thickness T ₀ (mm).
(7) Rigidity and softness (mm):
Calculated in accordance with JIS L1913: 2010 "General Nonwoven Fabric Test Method", "6.7 Rigidity and Softness", "6.7.3 41.5 ° Cantilever Method".
Five test pieces having a width of 25 mm × 150 mm were collected from the produced non-woven fabric, and the short sides of the test pieces were placed on a horizontal table having a slope of 45 ° so as to align with the scale baseline. The test piece was manually slid in the direction of the slope, and when the center point of one end of the test piece touched the slope, the moving length of the position of the other end was read by a scale. The moving length was measured on the front and back of the five test pieces, and the average value was calculated.
(8) Tactile evaluation:
Ten arbitrarily selected persons touched the surface of the non-woven fabric and evaluated according to the following criteria. The total score of the evaluation results for each non-woven fabric was used as the tactile evaluation of the non-woven fabric.
・ 3: The surface is particularly smooth and the tactile sensation is very good. ・ 2: The surface is smooth and the tactile sensation is excellent. ・ 1: The surface is sticky and the tactile sensation is inferior.

[Example 1]
From a rectangular mouthpiece with a number average molecular weight of 5500 and a copolymerization amount of 12% by weight, melted by an extruder using a copolymerized polyethylene terephthalate, a spinning temperature of 290 ° C., and a pore diameter of 0.30 mm. After cooling and solidifying the fibers spun with a single-hole discharge rate of 0.6 g / min, the fibers are pulled and stretched by compressed air with the ejector pressure set to 0.30 MPa with a rectangular ejector, and placed on a moving net. It was collected to obtain a non-woven fiber web made of copolymerized polyester filaments. For the obtained web, an embossing roll made of metal with a polka dot pattern engraved on the upper roll with an adhesive area ratio of 16% was used, and a pair of upper and lower thermal embossing rolls composed of a metal flat roll was used on the lower roll. , The linear pressure was 50 N / cm and the heat bonding temperature was 230 ° C. to obtain a spunbonded non-woven fabric having a grain size of 18 g / m ² . The evaluation results of the obtained spunbonded non-woven fabric are shown in Table 1.

[Example 2]
A spunbonded nonwoven fabric was obtained by the same method as in Example 1 except that the copolymerization amount of the polyethylene glycol contained was 8% by weight. The evaluation results of the obtained spunbonded non-woven fabric are shown in Table 1.

[Comparative Example 1]
A spunbonded nonwoven fabric was obtained by the same method as in Example 1 except that the copolymerization amount of the polyethylene glycol contained was 45% by weight. The evaluation results of the obtained spunbonded non-woven fabric are shown in Table 1.

[Comparative Example 2]
A spunbonded nonwoven fabric was obtained by the same method as in Example 1 except that the copolymerization amount of the polyethylene glycol contained was 2% by weight. The evaluation results of the obtained spunbonded non-woven fabric are shown in Table 1.

Examples 1 and 2 were the result of having excellent tactile sensation and high flexibility.
On the other hand, as shown in Comparative Example 1, when the copolymerization amount of polyethylene glycol was too large, there was a problem that the surface of the non-woven fabric was sticky and the tactile sensation was remarkably inferior, although it had flexibility. Further, as shown in Comparative Example 2, when the amount of copolymerization was too small, the rigidity and softness became high, and the sheet was hard and the texture was inferior.

Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. This application is based on a Japanese patent application filed on January 25, 2018 (Japanese Patent Application No. 2018-01254) and a Japanese patent application filed on September 28, 2018 (Japanese Patent Application No. 2018-183755). Is taken in as a reference.

Claims (2)

A spunbonded non-woven fabric composed of a single component fiber made of a copolymerized polyester-based resin obtained by copolymerizing 5% by weight or more and 40% by weight or less of polyethylene glycol with a polyester-based resin, and the ΔMR of the spunbonded non-woven fabric is 0.5%. A spunbonded non-woven fabric having a content of 15% or more. The spunbonded nonwoven fabric according to claim 1, wherein the polyester resin is polyethylene terephthalate.