JP2000282357A - Biodegradable filament nonwoven cloth and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a biodegradable nonwoven cloth having excellent strength, flexibility and wear resistance by including scattered point-like fused region in which constituting fibers comprising biodegradable thermoplastic aliphatic polyester filaments are mutually fused with each other. SOLUTION: This biodegradable nonwoven cloth having clear borders of scattered point-like fused region in which constituting fibers of biodegradable thermoplastic aliphatic polyester having >=85 deg.C melting point and selected from the group of poly(D-lactic acid), poly(L-lactic acid), a D-lactic acid/L-lactic acid copolymer, a D-lactic acid/hydroxycarboxylic acid copolymer or an L-lactic acid/hydroxycarboxylic acid copolymer, etc., or from the group of polybutylene succinate, polyethylene succinate, polybutylene adipate or polyethylene adipate or a copolymer containing their copolymer elements as main repeating units are mutually fused with each other by ultrasonic wave wedding process and the other non-fused region, and has 8-200 g/m2 fabric weight and >=3-degree of wear resistance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a biodegradable composition,
Regarding a long-fiber nonwoven fabric having excellent abrasion resistance as well as strength and flexibility and a method for producing the same, particularly medical and hygiene materials,
The present invention relates to a long-fiber non-woven fabric suitable as a living-related material such as a garbage collection bag or a toy bag, an industrial material for agriculture, horticulture, or civil engineering, and a method for producing the same.

[0002]

2. Description of the Related Art Research and development on long-fiber nonwoven fabrics using biodegradable thermoplastic polymers have been actively conducted. As a biodegradable thermoplastic polymer, for example, a group of polymers collectively referred to as aliphatic polyesters has biodegradability, and thus has attracted particular attention. Specifically, poly-L-lactic acid and poly-lactic acid Poly-α-hydroxy acids represented by -D-lactic acid or a copolymer thereof, a polyalkylene alkanoate comprising a condensation polymer of a glycol and a dicarboxylic acid such as polybutylene succinate or polyethylene succinate, or a polyalkylene alkanoate thereof; Examples thereof include copolymers and poly-ω-hydroxyalkanoates represented by polycaprolactone. JP-A-9-13285
No. 4 proposes a nonwoven fabric composed of long fibers mainly composed of polyalkylene alkanoate and obtained by thermocompression bonding, and this nonwoven fabric has a mechanical strength and flexibility that can be practically used. Although it is effective in having
There is a problem that the wear resistance is poor. JP-A-9-9
No. 5849 proposes a nonwoven fabric which is composed of long fibers mainly composed of a poly-α-hydroxy acid (polylactic acid) -based polymer and whose shape is maintained by partial thermocompression bonding. However, this nonwoven fabric is effective in that it has excellent flexibility while maintaining practically usable mechanical strength, but has a problem in abrasion resistance.

[0003]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems, has biodegradability, and is excellent not only in strength and flexibility but also in abrasion resistance. An object of the present invention is to provide a long-fiber nonwoven fabric suitable as a living-related material such as a bag or a bag, an industrial material for agriculture, horticulture or civil engineering, and a method for producing the same.

[0004]

The gist of the present invention is as follows. 1) It is composed of long fibers made of a biodegradable thermoplastic aliphatic polyester, and has a scattered fusion area in which the constituting long fibers are fused to each other, and the fusion area and the fusion A biodegradable long-fiber nonwoven fabric, characterized in that the boundary with the non-fused area outside the area is clear. 2) It is composed of filaments made of a biodegradable thermoplastic aliphatic polyester, and has a scattered fusion zone in which the filaments are fused to each other, and the fusion zone is ultrasonically fused. A biodegradable long-fiber nonwoven fabric formed by a dressing process. 3) When the melting point of this polymer is Tm ° C., the biodegradable thermoplastic aliphatic polyester is (Tm + 15) ° C. to (T m
(m + 90) ° C., melt-spun through a spinneret, cools and solidifies the spun yarn, and after drawing at a drawing speed of 3000 m / min or more by a drawing means such as an air sacker, is thinned.
The web is formed while being spread on the movable collecting surface while being spread, and the web is melted or softened by subjecting the web to a fusion process using an ultrasonic fusion processing apparatus. Forming a fused area formed by fusing the long fibers with each other in a scattered manner.

[0005]

The nonwoven fabric of the present invention is composed of long fibers made of a biodegradable thermoplastic aliphatic polyester. After the elapse of the period, the nonwoven fabric is almost completely decomposed by microorganisms and does not pollute the natural environment. The polymer constituting the long fiber according to the present invention is a thermoplastic aliphatic polyester having biodegradability, for example, a poly-α-hydroxy acid or a copolymer having the polymer element as a main repeating unit, or a polymer. Alkylene alkanoate or a copolymer containing this polymer as a main repeating unit.

First, poly-α-hydroxy acid polymers include, specifically, poly (D-lactic acid), poly (L-lactic acid), and a copolymer of D-lactic acid and L-lactic acid. , A copolymer of D-lactic acid and hydroxycarboxylic acid, a copolymer of L-lactic acid and hydroxycarboxylic acid, and a copolymer of D-lactic acid, L-lactic acid and hydroxycarboxylic acid. Among them, any polymer having a melting point of 80 ° C. or higher, or a blend thereof is exemplified. Here, examples of the hydroxycarboxylic acid in the case of a copolymer of lactic acid and hydroxycarboxylic acid include glycolic acid, hydroxybutyric acid, hydroxyvaleric acid, hydroxycaproic acid, hydroxyheptanoic acid, and hydroxycaprylic acid. Such a poly-α-hydroxy acid-based polymer preferably has a melting point of 80 ° C. or higher, and if the melting point is lower than 80 ° C., when a long-fiber nonwoven fabric is formed using this polymer. The resulting nonwoven fabric is not preferred because it becomes difficult to use it under high temperature conditions. Also,
This poly-α-hydroxy acid-based polymer is preferable in terms of fiber properties that can provide a number average molecular weight of about 20,000 or more, preferably 40,000 or more, and in view of the spinning property during production.

On the other hand, polyalkylene alkanoate-based polymers include, specifically, polybutylene succinate and
Polyethylene succinate, polybutylene adipate, and any polymer selected from the group of polyethylene adipate, or a copolymer containing a basic element of these polymers as a main repeating unit, or a blend thereof. . Such a polyalkylene alkanoate-based polymer preferably has a melting point of 80 ° C. or higher, and when the melting point is lower than 80 ° C., when a long-fiber nonwoven fabric is formed using this polymer, The resulting nonwoven fabric is not preferred because it becomes difficult to use it under high temperature conditions.

In the long fiber constituting the nonwoven fabric of the present invention, if necessary, other additives such as a matting agent, a pigment, a crystal nucleating agent and the like may be added to the polymer of the long fiber. You may add in the range which does not impair. Especially poly-α
In the case of a hydroxy acid polymer, when a nucleating agent such as talc, boron nitride, calcium carbonate, magnesium carbonate, titanium oxide or the like is added to the polymer, the crystallization of the fiber is promoted, and the obtained length is increased. It can improve the mechanical strength of the fiber, that is, the strength and heat resistance of the non-woven fabric, and can prevent the occurrence of fusion (so-called blocking) between spun yarns in the melt-spinning / cooling process during production. It is more preferable because it is possible. The addition of such a crystal nucleating agent is equivalent to 0.1.
1 to 3.0% by weight, preferably 0.5 to 2.0% by weight, whereby the crystallinity of the long fiber is 10 to 40%.
In the range.

The long fibers constituting the nonwoven fabric of the present invention may be composed of a poly-α-hydroxy acid polymer or a polyalkylene alkanoate polymer alone. A composite of a poly-α-hydroxy acid polymer or a polyalkylene alkanoate polymer may be used.
A composite of a hydroxy acid polymer and a polyalkylene alkanoate polymer may be used. The cross-sectional shape is arbitrary according to the purpose and application, such as a hollow cross section, a modified cross section, a parallel composite cross section, a multilayer composite cross section, a core-sheath composite cross section, a split composite cross section, etc. in addition to a normal round cross section. However, from the viewpoint of biodegradability, a hollow cross section, a modified cross section, a split composite cross section, or the like is preferable.

[0010] The long fibers constituting the nonwoven fabric of the present invention preferably have a single-fiber fineness in the range of 1 to 12 denier. When the single-fiber fineness is less than 1 denier, the spinnability decreases in the melt spinning process, while when the single-fiber fineness exceeds 12 denier, not only the cooling property of the spun yarn in the melt-spinning process deteriorates, but also This impairs the flexibility of the resulting non-woven fabric, both of which are not preferred.

The nonwoven fabric of the present invention has a basis weight of 8 to 20.
It is preferably in the range of 0 g / m ² . 8g weight
If it is less than / m ² , the basis weight is too low, and it is difficult to stably produce the nonwoven fabric by the spun bond method. On the other hand, if the basis weight exceeds 200 g / m ² , the texture of the obtained nonwoven fabric decreases. Therefore, it is not preferable.

[0012] The nonwoven fabric of the present invention has a scattered fusion zone in which the constituent long fibers are fused to each other, and the form of the nonwoven fabric is maintained by forming the fusion zone. It is. In other words, this nonwoven fabric is one in which the constituent long fibers are fused to each other only in the scattered fusion zone, and such a structure improves the shape retention of the nonwoven fabric and has flexibility. Will do. Such a scattered fusion zone is formed by a so-called ultrasonic fusion process, and has a frequency of about 20 KHz, an ultrasonic oscillator called a normal horn, and a dot or a circle on the circumference. It is formed by using an ultrasonic fusion device including a pattern roll having a belt-shaped convex protrusion, and is made by fusing long fibers that are in contact with a portion corresponding to the convex protrusion. The ultrasonic welding device that can be used in the present invention includes a known device as described above, that is, an ultrasonic oscillator called a normal horn having a frequency of about 20 KHz, and a point-shaped or band-shaped convex protrusion on the circumference. And a pattern roll provided. The pattern roll is disposed below the ultrasonic oscillator, and the object is passed between the ultrasonic oscillator and the pattern roll. The convex protrusions provided on the pattern roll may be in one row or plural rows,
In the case where the arrangement is a plurality of rows, the arrangement may be either parallel or staggered. During the fusion process, the horn is pressurized by applying air pressure to the horn.

The nonwoven fabric of the present invention has a specific area and a specific arrangement of scattered fusion zones with respect to the total surface area of the nonwoven fabric.
The individual fusion zones do not necessarily have to be circular in shape, but may be, for example, cruciform,-, rhombic, T-shaped, □ in addition to circular.
The shape may be any shape such as a shape and a shape, but it is preferable that the ratio (%) of the area of the entire fused area to the total surface area of the nonwoven fabric satisfies the range of 4 to 50. When the ratio of the area of the entire fusion zone to the total surface area of the nonwoven fabric is less than 4%, the strength of the nonwoven fabric obtained by integrally forming the scattered fusion zone by using an ultrasonic fusion device can be reduced. If the area ratio does not improve sufficiently, while the area ratio exceeds 50%,
None of them is preferable because the obtained nonwoven fabric is roughly cured. It is preferable that the scattered fusion zone has an arrangement density (points / cm ² ) of the fusion zone of 7 to 80.
When the disposition density of this fusion zone is less than 7 points / cm ² ,
When the strength of the obtained nonwoven fabric is not only lowered, but also the spots are strongly formed, on the other hand, when the area density exceeds 80 points / cm ² ,
None of them is preferable because the obtained nonwoven fabric is roughly cured.

In the nonwoven fabric of the present invention, the boundary between the fusion zone and the non-fusion zone outside the fusion zone is sharp, and such a boundary is achieved by the above-mentioned specific ultrasonic fusion process. Is done. In this nonwoven fabric, an intermediate region between the fused region and the non-fused region is provided between a fused region in which the constituent long fibers are fused to each other and a non-fused region in which the long fibers are kept free. That is, since there is almost no region where a portion where the long fibers are fused together and a portion where the long fibers are not fused are present, for example, when an external force such as tension is applied, the fusion point of the long fibers in the intermediate region is first determined. The breaking mechanism that starts peeling and then collapses the fused area does not work. Therefore, not only the high strength but also excellent abrasion resistance is obtained for the nonwoven fabric that has been subjected to the partial thermocompression bonding using the conventional embossing roll. Is provided. Further, in this nonwoven fabric, the long fibers present in the non-fused area outside the fused area maintain a free state without being partially fused, so that the flexibility is further improved. In addition,
Originally, poly-α-hydroxy acid-based polymers were said to have high thermal conductivity among aliphatic polyesters and were difficult to be fused. The ultrasonic fusing process employed in the present invention does not directly transfer heat to the object to be processed as in the case of using a conventional embossing roll, but uses the energy of ultrasonic waves to vibrate the long fiber itself. This causes friction between the long fibers and causes the long fibers to fuse with each other due to a heat generation phenomenon caused by the friction.
This is particularly effective in the case of a hydroxy acid polymer.

In the nonwoven fabric of the present invention, the tensile strength of the nonwoven fabric is preferably not less than 7 kg / 5 cm width in terms of basis weight of 100 g / m ² . If the tensile strength based on a basis weight of 100 g / m ² is less than 7 kg / 5 cm width, the strength is too low, and it becomes difficult to put the nonwoven fabric into practical use, which is not preferable.

The non-woven fabric of the present invention has a compression stiffness of 200.
It is preferably 0 g or less. Compression stiffness is 2000
If it exceeds g, the resulting nonwoven fabric is hard and poor in flexibility, and although it depends on the use, it is generally not preferred.

In the nonwoven fabric of the present invention, the abrasion resistance of the nonwoven fabric is preferably at least class 3. This abrasion resistance is defined as J
6.17.3 [Method C] Taber Type Method of IS L1096]
Are visually observed and evaluated in five steps. The improvement in abrasion resistance is achieved by the above-mentioned specific ultrasonic fusion processing. If the abrasion resistance is less than 3rd grade, the surface of the non-woven fabric has a lot of fluffing and causes a problem during use. This is not preferred.

Next, the method for producing the nonwoven fabric of the present invention will be described. The nonwoven fabric of the present invention can be efficiently produced by a so-called spunbond method. That is, the above-described aliphatic polyester is heated and melted, discharged from a spinneret, and the obtained spun yarn is cooled using a conventionally known cooling device such as horizontal spraying or annular spraying. After the yarn group discharged from the traction means is spread by using a suction device or other known traction means, the fiber group is spread and spread on a moving deposition device such as a conveyor made of a mesh screen. Let it be a web. Next, a scattered fusion area is formed on the web formed on the moving deposition apparatus using the above-described ultrasonic fusion apparatus, and the form is maintained to obtain a long-fiber nonwoven fabric.

In the present invention, when producing a long-fiber nonwoven fabric by the so-called spunbonding method, it is preferable that the drawing speed of the spun yarn is 3000 to 6000 m / min.
When the drawing speed at the time of drawing and narrowing the spun yarn is less than 3000 m / min, the oriented crystallization of the polymer does not progress, the strength of the obtained nonwoven fabric is not improved, and the decomposition rate is too high. . Conversely, when the drawing speed exceeds 6000 m / min, the yarn-making properties are rapidly deteriorated, and the yarn breaks easily. In the case where the polymer is a poly-α-hydroxy acid-based polymer, it is more preferable to add the above-described nucleating agent because the cooling property of the spun yarn at the time of melt spinning is improved.

[0020]

The nonwoven fabric of the present invention is composed of long fibers of a biodegradable thermoplastic aliphatic polyester. Therefore, after a certain period of use, the nonwoven fabric is almost completely decomposed by biodegradation. This eliminates the need for waste disposal, and does not pollute the natural environment. Further, in this nonwoven fabric, the boundary between the scattered fusion zone where the constituent long fibers are fused to each other and the non-fusion zone outside the fusion zone is clear, and the fusion zone and the non-fusion zone. Since there is almost no intermediate region between the two regions, high strength and excellent abrasion resistance are provided. Further, since the long fibers existing in the non-fused area outside the fused area maintain a free state without being partially fused, flexibility is improved.

[0021]

The present invention will be described below in detail with reference to examples. The present invention is not limited by these examples. In the examples, each property value was obtained as follows. (1) Melting point (° C.): The temperature giving the extreme value of the melting endothermic curve obtained by measuring the temperature at a heating rate of 20 ° C./min using a differential scanning calorimeter DSC-7 manufactured by Perkin Elmer Co., Ltd. ° C). (2) Melt flow rate value (hereinafter abbreviated as MFR value) (g / 10 min): Measured according to the method described in ASTM D1238. The melting temperature was 210 ° C. and the applied load was 2.16 kg. (3) Single yarn fineness (denier): The diameter of 50 fibers in a web state was measured with a microscope, and the average value of the fineness obtained by density correction was defined as single yarn fineness (denier). (4) Weight per unit area (g / m ² ): 20 samples from the standard sample
After preparing five sample pieces of 5 cm × 5 cm width to reach equilibrium moisture, the weight (g) of each sample piece was weighed, and the average of the obtained values was converted into a unit area, and the basis weight ( g /
m ² ). (5) KGSM tensile strength (kg / 5cm width): JIS
It was measured according to the stripping method described in L1906.
That is, five sample pieces each having a sample length of 20 cm and a sample width of 5 cm were prepared, and a constant-speed elongation type tensile tester (Tensilon UTM-4-1-100 manufactured by Orientec) was used.
Each sample piece is stretched at a holding interval of 10 cm and a pulling speed of 20 cm / min, and a maximum tensile strength (kg / 5 cm width) is obtained.
The average value of the obtained maximum tensile strength was 100 g / m2.
^The value converted per ² was defined as the KGSM tensile strength (kg / 5 cm width) of the nonwoven fabric. (6) Bending softness (g / 100 g / m ² ): 5 cm long
Five specimens each having a width of 10 cm were prepared, and each specimen was bent in the lateral direction to form a cylindrical shape. Next, a constant speed elongation type tensile tester (Tensilon UTM-4-1- manufactured by Orientec Co., Ltd.)
100), a compression speed of 5 in the cylindrical axis direction for each sample.
cm / min to determine the maximum load value (g), and calculate the average value of the obtained maximum load values (g) per unit weight of 100 g / m ^2, and calculate the compression rigidity (g / 100 g / m 2). ² ) It should be noted that the smaller the value, the better the flexibility. (7) Abrasion resistance (grade): JI using a Gakushin type friction tester
The result of measurement according to 6.10.37.3 [Method C, Taber type method of SL1096] is visually observed, and if the nonwoven fabric surface has no abrasion and no fuzz is observed, the nonwoven fabric surface is class 5; Grade 1 and grade 4
Classified into 2 grades and evaluated in a total of 5 grades. The number of reciprocating friction was set to 100 times. (8) Biodegradability: A sample piece was buried in soil, taken out after one year and two years, and the form of the sample piece was observed, and evaluated in the following two stages. ：: Until one year after the embedding of the sample, the shape of the nonwoven fabric was maintained, and the sample was broken after two years. Alternatively, the shape of the nonwoven fabric was broken by two years after the embedding of the sample. D: The nonwoven fabric was retained in the form of the nonwoven fabric even two years after the embedding of the sample.

Example 1 Polylactic acid having a melting point of 170 ° C., a number average molecular weight of 62,300 and an MFR value of 47 g / 10 min [copolymerization ratio (molar ratio of D-form / L-form) = 1.7 / 98.3] After the chip was melted, it was melt-spun from a spinneret having a spinning hole with a hole diameter of 0.3 mm at a spinning temperature of 220 ° C. and a single hole discharge rate of 1.6 g / min. After the spun yarn is cooled by the cooling device, it is subsequently drawn and thinned at a drawing speed of 5,000 m / min by an air sucker provided below the spinneret, and is spread and moved by a known spreader. The web was collected and deposited on a screen conveyor.
Next, a horn (ultrasonic oscillator) having a frequency of 19.5 KHz and a pressure contact point, that is, a point-like convex protrusion on the circumference are disposed at a density of 22 points / cm ² and a pressure contact area ratio, that is, the total surface area. A fusion process is performed by passing through an ultrasonic fusion device comprising a pattern roll arranged so that the area ratio of the total pressure contact becomes 15%, and the single yarn fineness is 3.0 denier and the basis weight is 30 g / m ^2. Was obtained. In addition,
At the time of this ultrasonic welding, the reciprocating amplitude of the horn is set to 7
It was 6 microns. Table 1 shows various properties of the obtained nonwoven fabric.

Example 2 The same procedure as in Example 1 was carried out except that the reciprocating amplitude of the horn during the ultrasonic welding process was set to 100 μm. m ²
Was obtained. Table 1 shows various properties of the obtained nonwoven fabric.

Example 3 A long-fiber nonwoven fabric was obtained in the same manner as in Example 1 except that the basis weight was 60 g / m ² . Table 1 shows various properties of the obtained nonwoven fabric.

Example 4 The same procedure as in Example 2 was carried out except that the single hole discharge amount was 4.3 g / min and the drawing speed was 5500 m / min, and the basis weight of the single fiber fineness was 7.0 denier long fibers. Is 30 g / m ²
Was obtained. Table 1 shows various properties of the obtained nonwoven fabric.

Example 5 In the ultrasonic fusing process, a pressure roll, that is, a point-like convex protrusion was provided with a pattern density of 64 points / cm ² and a pattern contact area ratio of 37% was used. In the same manner as in Example 1, a long-fiber nonwoven fabric having a single fiber fineness of 3.0 denier and a basis weight of 30 g / m ² was obtained. Table 1 shows various properties of the obtained nonwoven fabric.

Comparative Example 1 In the same manner as in Example 1 except that a partial thermocompression bonding device composed of an embossing roll heated to a temperature of 125 ° C. and a metal roll having a smooth surface was used instead of the ultrasonic fusing device,
A long-fiber nonwoven fabric with a basis weight of 30 g / m ² was obtained. Table 1 shows various properties of the obtained nonwoven fabric.

Comparative Example 2 The temperature of the embossing roll and the metal roll having a smooth surface was set to 140
The same as Comparative Example 1 except that the temperature was
A long-fiber nonwoven fabric of 0 g / m ² was obtained. Table 1 shows various properties of the obtained nonwoven fabric.

Comparative Example 3 The basis weight of a single-filament long fiber of 7.0 denier was set in the same manner as in Comparative Example 2 except that the single hole discharge rate was 4.3 g / min and the drawing speed was 5500 m / min. Is 30 g / m ²
Was obtained. Table 1 shows various properties of the obtained nonwoven fabric.

[0030]

[Table 1]

The nonwoven fabrics obtained in Examples 1 to 5 were all biodegradable, high in strength, rich in flexibility, and excellent in abrasion resistance. In contrast, Comparative Example 1
Each of the nonwoven fabrics obtained in Nos. 1 to 3 had biodegradability, but was inferior to the above examples in the following points. That is, any nonwoven fabric is subjected to partial thermocompression bonding using a heated embossing roll,
Between the fused area where the constituent long fibers are fused to each other and the non-fused area where the long fibers are kept free, the part where the long fibers are fused or not fused Since there is an intermediate region in which the part is mixed, the strength and abrasion resistance are not improved as in the above embodiment.

[0032]

The nonwoven fabric of the present invention is composed of long fibers of a biodegradable thermoplastic aliphatic polyester. Therefore, after a certain period of use, the nonwoven fabric is almost completely decomposed by biodegradation. There is no need to collect and dispose, and the natural environment is not polluted. In addition, this nonwoven fabric has a scattered fusion zone in which constituent long fibers are fused to each other, and there is almost no intermediate region between both the fusion zone and the non-fusion zone. It has excellent abrasion resistance, and furthermore, the long fibers present in the non-fused area outside the fused area remain free without being partially fused, and therefore have flexibility. Also improve.

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Claims (10)

[Claims] Claims: 1. A filament made of a biodegradable thermoplastic aliphatic polyester and having a scattered fusion zone where the filaments are fused to each other. A biodegradable long-fiber nonwoven fabric, characterized in that the boundary between the non-fused area and the non-fused area is sharp. 2. A fusible area composed of biodegradable thermoplastic aliphatic polyester long fibers, wherein the constituent long fibers are fused to each other, and said fused area is A biodegradable long-fiber nonwoven fabric formed by ultrasonic fusion. 3. The thermoplastic aliphatic polyester is composed of poly (D-lactic acid), poly (L-lactic acid), D-lactic acid and L-lactic acid.
A copolymer of lactic acid, a copolymer of D-lactic acid and hydroxycarboxylic acid, a copolymer of L-lactic acid and hydroxycarboxylic acid, and a copolymer of D-lactic acid, L-lactic acid and hydroxycarboxylic acid The biodegradable long-fiber nonwoven fabric according to claim 1, wherein the nonwoven fabric is a polymer selected from the group consisting of polymers and having a melting point of 80 ° C. or higher, or a blend thereof. 4. The method according to claim 1, wherein the thermoplastic aliphatic polyester comprises polybutylene succinate, polyethylene succinate,
The melting point of the polymer selected from the group consisting of polybutylene adipate, polyethylene adipate, and a copolymer having a basic element of these polymers as a main repeating unit is 80 ° C.
The biodegradable long-fiber nonwoven fabric according to claim 1, which is any one of the above polymers or a blend thereof. 5. The biodegradable long-fiber nonwoven fabric according to claim 1, wherein the basis weight is 8 to 200 g / m ² . 6. The biodegradable long-fiber nonwoven fabric according to claim 1, wherein the abrasion resistance of the nonwoven fabric is at least class 3. 7. The biodegradable thermoplastic aliphatic polyester is obtained by setting the melting point of the polymer to Tm ° C. (Tm + 1
5) Melt spinning through a spinneret at a temperature of from 0 ° C. to (Tm + 90) ° C., and the spun yarn is cooled and solidified, and drawn and thinned by a drawing means such as an air sucker at a drawing speed of 3000 m / min or more. Later, the web is formed while being spread while being spread on the movable collecting surface, and a web is formed by performing a fusion process using an ultrasonic fusion processing apparatus. A method for producing a biodegradable long-fiber nonwoven fabric, which comprises softening and forming a fused area formed by fusing the long fibers with each other. 8. A thermoplastic aliphatic polyester comprising poly (D-lactic acid), poly (L-lactic acid), D-lactic acid and L-lactic acid.
A copolymer of lactic acid, a copolymer of D-lactic acid and hydroxycarboxylic acid, a copolymer of L-lactic acid and hydroxycarboxylic acid, and a copolymer of D-lactic acid, L-lactic acid and hydroxycarboxylic acid 8. The method for producing a biodegradable long-fiber nonwoven fabric according to claim 7, wherein the polymer is a polymer selected from the group consisting of polymers having a melting point of 80 ° C. or higher and a blend thereof. . 9. A thermoplastic aliphatic polyester comprising: polybutylene succinate; polyethylene succinate;
The melting point of the polymer selected from the group consisting of polybutylene adipate, polyethylene adipate, and a copolymer having a basic element of these polymers as a main repeating unit is 80 ° C.
The method for producing a biodegradable long-fiber nonwoven fabric according to claim 7, wherein the non-woven fabric is any one of the above polymers or a blend thereof. 10. The method for producing a biodegradable long-fiber nonwoven fabric according to claim 7, wherein the abrasion resistance of the nonwoven fabric is at least class 3.