KR20140119351A - Dimensional Stable Spunbonded Nonwoven for Primary Carpet Backing, and Method for Manufacturing the Same - Google Patents

Abstract

The present invention relates to a spunbonded nonwoven fabric which has improved dimensional stability at high temperature to form a carpet base fabric having excellent dimensional stability even in a process of high temperature coating and heat treating, and to a method for manufacturing the same. According to the method for manufacturing a spunbonded nonwoven fabric for a carpet base fabric of the present invention, a spunbonded nonwoven fabric which has excellent intensity properties, has low thermal shrinkage at high temperature of 180°C, and also has flexibility of being suitably stretched under a tensile force applied can be manufactured, and a carpet manufactured by using the nonwoven fabric which maintains excellent properties of nonwoven fabric while preventing side parts from being lifted by influence of heat and water is manufactured to have high quality with improved dimensional stability.

Description

Technical Field [0001] The present invention relates to a spunbonded nonwoven fabric for carpet bubbles having improved morphological stability and a method for manufacturing the same,

The present invention relates to a spunbonded nonwoven fabric for carpet bubbles and a method of manufacturing the same, which enables the shape of a carpet to be stably maintained in a high-temperature carpet manufacturing process.

The spunbond nonwoven fabric is highly productive and has high strength and low toughness properties and is used in many industrial fields. Since it is excellent in strength and drainage property, it is used for civil engineering and construction purposes and has excellent durability against price It is also widely used for automobiles.

Especially, recently, it has been found that the spunbonded nonwoven fabric has excellent shape stability and dust particle collecting ability, and it is widely used as a filter material. It has excellent uniformity and excellent shape stability at a high temperature, It is also used for primary tufting carpet backing.

Carpet bubbles are known to be difficult to manufacture during use of polyester spunbonded nonwovens because the carpet bubbles penetrate the nonwoven fabric during the tufting process of carpet yarn (BCF) onto the nonwoven fabric, The filament fibers constituting the nonwoven fabric are damaged or broken, and the property values of the nonwoven fabric such as strength, elongation and tear strength are lowered.

In order to solve the above problems, various methods have been proposed. In Korean Patent Registration No. 1079804 proposed by the present applicant, properties such as tensile strength, elongation, tear strength and heat shrinkage after the tufting process Excellent long-fiber spunbond nonwoven fabric and a method of producing the same.

The present invention relates to a method for producing a web having a low melting point copolyester and a general polyester fiber mixed with a low melting point copolyester and a general polyester made of polyethylene terephthalate or a copolymer thereof, To melt the copolyester fibers having a low melting point, thereby improving the physical properties of the nonwoven fabric.

However, in order to secure the adhesive force for bonding the fibers, the above-mentioned invention must contain a large amount of copolyester having a low melting point in the nonwoven fabric, and they are dissolved during the heat bonding process to increase the bonding points between the nonwoven fabric fibers, The spunbonded nonwoven fabric produced in this way has a high heat shrinkage ratio and a smooth surface so that it is required to be used like a carpet baregege which is exposed to high temperature and dustiness such as dust collecting The filter is not suitable for the filter.

The present applicant also discloses in Korean Patent Registration No. 1194358 a first polyester polymer having a melting point of 250 DEG C or higher and a second polyester polymer having a melting point lower than that of the first polyester polymer by 20 DEG C or more, Stretched to form polyester filament fibers, and then laminated and thermally bonded in the form of a web.

The present invention can be produced by thermally adhering filament fibers easily without adding a separate needle punching process or the like, so that it is useful as a base material for carpets and has excellent tensile strength, elongation and tear strength even after the tufting process of the carpet manufacturing process However, since the nonwoven fabric manufactured by the above method has a high heat shrinkage, the shape of the carpet is likely to be deformed during a high-temperature carpet manufacturing process, and a latent stress due to a difference in elongation between the coating material of the carpet and the nonwoven fabric is generated So that a curl phenomenon of the carpet product is caused.

In addition, the present applicant has proposed a method for producing a composite nonwoven fabric having excellent tensile strength, elongation and tear strength in Korean Patent Publication No. 2012-0001963. The present invention relates to a method for producing a composite nonwoven fabric, A step of mounting the meltblown nonwoven fabric on a bond-bonded nonwoven fabric, entangling the same by water punching, and then drying.

The present invention can provide an effect that the deterioration of the physical properties after the tufting process of the carpet production is not significant, but two or more kinds of nonwoven fabric materials must be prepared and processed in a separate process, and a polypropylene Is used as a heat-bonding material, there is a disadvantage that it can not be used for applications such as a carpet for building flooring manufactured by coating heat treatment at 180 ° C or higher.

Accordingly, it is still required to develop a nonwoven fabric which is excellent in physical properties such as strength and elongation, and has flexibility, so that the shape of the nonwoven fabric can be stably maintained even at a high temperature heat treatment process of the carpet.

Disclosure of the Invention The present invention provides a spunbonded nonwoven fabric capable of realizing a carpet bubble having improved shape stability at a high temperature and excellent in shape stability even during a high temperature coating process and a heat treatment process in a carpet manufacturing process and a method for manufacturing the spunbonded nonwoven fabric .

In order to solve the above problems, the present invention provides a thermoplastic resin composition comprising 90 to 96% by weight of a high melting point polyester having a melting point of 250 to 270 DEG C and 4 to 10% by weight of a low melting point copolymer having a melting point of 180 to 210 DEG C, To 40% and a heat shrinkage ratio of 0.2 to 0.6%, wherein the shape stability of the spunbond nonwoven fabric is improved.

The present invention also relates to a method for producing a low-melting-point copolymer, comprising the steps of: mixing a high melting point polyester having a melting point of 250 to 270 ° C and a low melting point copolymer having a melting point of 180 to 210 ° C at a ratio of 90 to 96: Forming a web of filaments formed by the radiation; And thermally adhering the web. The present invention also provides a method of manufacturing a spunbonded nonwoven fabric for carpet bubbles having improved morphology stability.

At this time, the high melting point polyester is preferably polyethylene terephthalate or polynaphthalene terephthalate.

The low-melting-point copolymer may be one selected from the group consisting of adipic acid-copolymerized polyester, isophthalic acid-copolymerized polyester, adipic acid and isophthalic-copolymerized polyester, polybutylene terephthalate, polylactic acid and polyamide It is preferably at least any one selected.

It is preferable that the low melting point copolymer is copolymerized with the high melting point polyester with adipic acid or isophthalic acid.

According to the method for producing a spunbonded nonwoven fabric for carpet bubbles of the present invention, it is possible to produce a spunbonded nonwoven fabric having excellent physical properties and flexibility at a high temperature of 180 DEG C while having a moderate stretching under a tensile force given by a small heat shrinkage.

In addition, the carpet manufactured using the nonwoven fabric can produce high quality carpets with improved shape stability by suppressing the depression due to the influence of heat and water while maintaining excellent physical properties of the nonwoven fabric.

Disclosed herein is a spunbonded nonwoven fabric for carpet bubbles, which is excellent in shape stability and flexibility at high temperature to improve the durability of the carpet, and a method for producing the spunbonded nonwoven fabric.

The spunbonded nonwoven fabric for carpet foam according to the present invention comprises 90 to 96% by weight of a high melting point polyester having a melting point of 250 to 270 DEG C and 4 to 10% by weight of a low melting point copolymer having a melting point of 180 to 210 DEG C, To 40% and a heat shrinkage ratio at 180 ° C of 0.2 to 0.6%, and thus has excellent characteristics of shape stability at high temperature.

The present invention also relates to a process for producing a low-melting-point copolymer having a melting point of 250 to 270 ° C and a low melting point copolymer having a melting point of 180 to 210 ° C at a ratio of 90 to 96: 4 to 10 wt% Forming a web with the formed filaments, and thermally bonding the web.

In order to manufacture a spunbond for carpet bubbles having improved morphological stability, a product having a low shrinkage rate at a high temperature of 180 ° C or higher should be manufactured in a continuous process, and the shrinkage ratio is determined in a machine direction (MD) , CD) should be able to express the same level.

During the manufacturing process of the carpet, the carpet yarn is passed through a nonwoven fabric in a vertical direction on a spunbonded nonwoven fabric by using a needle, and subjected to a tufting process of binding and transplanting. In order to fix the shape and durability of the carpet passing through the tufting process It is inevitably given a tensile force in the direction of the product in the process of coating with a material such as polyvinyl chloride, polyurethane, asphalt at high temperature and then heat treatment and drying to complete the final product.

When the tensile force is applied under such a high temperature environment, the nonwoven fabric should be appropriately stretched at a rate similar to that of the coating material while the heat shrinkage rate is low, so that the desired fabric width can be maintained without loss of material.

However, the resin used in the conventional nonwoven fabric for carpet bubbles is not satisfactory because it is designed to be melted at a high temperature of 210 ° C or higher or lower than 180 ° C and to contain 10 wt% or more of the nonwoven fabric and deformation due to heat shrinkage occurs. In the present invention, the melting point of the low-melting-point copolymer is maintained at 180 to 210 ° C, and the nonwoven fabric is contained in an amount of 4 to 10 wt% so that the form can be stably maintained even when the high-temperature heat treatment is performed in the carpet manufacturing process.

In general, the coating, heat treatment, and drying temperature of the carpet used for innerwear is less than about 180 ° C. Therefore, in order to produce a spun-bonded nonwoven fabric for carpet having excellent morphological stability according to the present invention, the melting temperature of the low melting- 180 ~ 210 ℃ should be maintained.

If the melting point of the low-melting-point copolymer is lower than 180 ° C, the low-melting copolymer tends to melt during the carpet manufacturing process and tends to cause breakage of the foaming sheet, and the heat shrinkage increases. As a result, the width and length of the finished carpet article become insufficient, The difference in heat shrinkage causes the edge of the carpet product to curl up at the sides of the carpet.

When the melting point of the low melting point copolymer is 210 占 폚 or more, the heat shrinkage rate of the nonwoven fabric is stabilized, so that the sheet is not cut or the width and length of the finished article are insufficient during the carpet manufacturing process. However, , Since the flexibility of the nonwoven fabric is lowered in the drying process, the nonwoven fabric is not stretched so that there is a difference in the elongation percentage of the flexible material such as polyvinyl chloride, polyurethane, and asphalt coated on the bottom of the nonwoven fabric.

Such minute difference is not a problem in the product immediately after the production, but as the use period of the carpet is increased, the potential stress due to the difference in elongation between the coating material and the nonwoven fabric causes the carpet to peel off.

In general, when a polyester spunbonded nonwoven fabric is produced, in order to obtain excellent physical performance, the content of the low melting point resin used for the heat adhesive is used in excess of 10 wt%, preferably 15 wt% or more In this case, since the fibers are closely adhered to each other, the movement between the fibers is restricted, and the polyester fibers are damaged by the penetration of the needles in the tufting process of the carpet, so that the tensile strength is lowered.

In order to solve this problem, in the present invention, the low melting point copolymer is contained in an amount of 4 to 10 wt% of the nonwoven fabric so that the bonding points between the fibers are maintained at a certain level to prevent damage to the fibers. In the high temperature coating, heat treatment, Appropriate flexibility is imparted to the nonwoven fabric to improve the shape stability of the final product carpet.

When the content of the low melting point copolymer is lowered to 10 wt% or less, the tensile strength of the nonwoven fabric itself is lowered, but the tensile strength retention after tufting is excellent. In more detail, the high melting point polyester fibers constituting the non- The tensile strength of the nonwoven fabric is reduced due to a decrease in the number of bonding points of the low melting point copolymer. However, when the needles penetrate the nonwoven fabric during tufting, the bonding force between the fibers is low.

Accordingly, the tensile strength of the nonwoven fabric after tufting is higher than that of the nonwoven fabric having a low melting point copolymer content exceeding 10 wt%, and as a result, a carpet having excellent strength can be produced. Usually, the low melting point copolymer is more expensive than the high melting point polyester Because it is expensive, it is advantageous in terms of manufacturing cost as it is used less.

However, if the content of the low melting point copolymer is further reduced and adjusted to less than 4 wt%, the tensile strength of the nonwoven fabric may be too low to increase the problem of fracture without being able to withstand the tensile force in the tufting, coating, heat treatment and drying processes.

The high melting point polyester of the present invention is not limited to the use of a polyester resin having a melting point of 250 to 270 캜. For example, polyethylene terephthalate, polynaphthalene terephthalate and the like can be applied have.

The low melting point copolymer can be polyester having a melting point adjusted to 180 ~ 210 ° C by mixing additives such as adipic acid or isophthalic acid in the polyester polymerization process and has a melting point of 180 Polybutylene terephthalate, polylactic acid, and polyamide may also be used.

The low-melting-point copolymer is preferably a mixture of the same kind of polyester as the high-melting-point polyester material with an additive. In the heat-bonding step, the low-melting-point copolymer polyester is melted, It can be easily bonded to the high-melting polyester which is the same material while being bonded, thereby improving the strength of the nonwoven fabric and lowering the shrinkage ratio more effectively.

Since the spunbonded nonwoven fabric of the present invention is manufactured by thermally adhering, the filament fibers are thermally adhered to each other even if the needle punch process is not carried out separately. Therefore, the manufacturing process of the nonwoven fabric is simple and the filament fibers are prevented from being damaged in the needle punching process Since the bonding of the fibers is performed by heat rather than by external force, the spun bond nonwoven fabric having a bulky structure can be obtained because no change in the finish is obtained.

Hereinafter, the present invention will be described in more detail with reference to the following examples, comparative examples and test examples.

It is to be understood, however, that the invention is not to be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Will be apparent to those skilled in the art to which the present invention pertains.

≪ Example 1 >

The high melting point polyester having an intrinsic viscosity of 0.655 and a melting point of 254 캜 was melted at 288 캜 and discharged through a spinneret. Adipic acid was added in an amount of 22 mol / wt% Was prepared, melted at 288 캜, and then discharged through the same spinning nozzle to spin up the composite.

At this time, the content ratio of the high melting point polyester filament and the low melting point copolymerizing polyester filament was adjusted to 94: 6 by weight.

The filaments formed by the composite spinning were rapidly drawn at a speed of 5000 m / min using an air ejector, spread using a collision plate diffusion method, and then laminated in a web shape while being collected on a conveyor belt.

The high melting point polyester filament constituting the web has a linear density of about 8.5 denier, the low melting point copolymerized polyester filament has a linear density of about 3.4 denier, the manufactured web has a weight of 90 gsm (grams per square meter) The moving speed was 32 m / min.

Subsequently, the web was passed between calender rollers maintained at 130 DEG C and 35 N / cm, and heated air of 194 DEG C was applied to produce a spunbonded nonwoven fabric.

≪ Example 2 >

In Example 1, except for using a copolymer polyester having a melting point of 180 ° C added with 25 mol / wt% of adipic acid and 8 mol / wt% of isophthalic acid as the low melting point copolymer polyester, 1, a spunbonded nonwoven fabric was produced.

≪ Example 3 >

In the same manner as in Example 1, except that the copolymer polyester having a melting point of 210 캜 was used as the low melting point copolymer polyester in Example 1, in which 18 mol / wt% of adipic acid was added to the spunbond nonwoven fabric .

<Example 4>

A spunbonded nonwoven fabric was prepared in the same manner as in Example 1, except that the content ratio of the high melting point polyester filament and the low melting point copolymerizing polyester filament was adjusted to 96: 4 by weight in Example 1.

&Lt; Example 5 >

A spunbonded nonwoven fabric was prepared in the same manner as in Example 1, except that the content ratio of the high melting point polyester filament and the low melting point copolymer polyester filament was adjusted to 90:10 by weight.

&Lt; Comparative Example 1 &

In the same manner as in Example 1, except that a copolymer polyester having a melting point of 170 캜 was used as the low melting point copolymer polyester in Example 1 and the hot air adhesion temperature of the web was adjusted to 174 캜, Nonwoven fabric was produced.

&Lt; Comparative Example 2 &

In the same manner as in Example 1, except that the copolymer polyester having a melting point of 214 캜 was used as the low melting point copolymer polyester in Example 1 and the hot air adhesion temperature of the web was adjusted to 219 캜, Nonwoven fabric was produced.

&Lt; Comparative Example 3 &

In Example 1, except that the content ratio of the high melting point polyester filament and the low melting point copolymerizing polyester filament was set to 96.4: 3.6 by weight and the hot air adhesion temperature of the web was finely adjusted to 196 캜, To prepare a spunbonded nonwoven fabric.

&Lt; Comparative Example 4 &

In Example 1, except that the content ratio of the high melting point polyester filament and the low melting point copolymer polyester filament was set to 89:11 by weight and the hot air adhesion temperature of the web was finely adjusted to 193 ° C, To prepare a spunbonded nonwoven fabric.

<Test example> Measurement of physical properties

The prepared spunbonded nonwoven fabric was tufted using a small tufting machine having a width of 1.0 m. The operating conditions of the tufting machine were a pile height of 3.0 mm, a gauge of 1/10 inch, a stitch 1 / 13 inch, running speed of 600 rpm, and the carpet yarn (BCF) used was a single loop type carpet using 1200 denier 96 filament triangular cross-section yarn made of nylon 6 manufactured by Hyosung Co. .

Then, the polyvinyl chloride coating solution was adhered to the backside of the tufting carpet at 4400 gsm to carry out the coating process. The maximum temperature of the heat treatment and drying process was maintained at 180 ° C to prepare the carpet at a speed of 6 m / min.

The finished carpet was cut to 50 ㎝ in width and 50 ㎝ in length, which is the general sales and usage standard, and the final carpet product was completed.

The physical performances of the spunbonded nonwoven fabrics prepared by the method according to the present invention and the comparative examples were measured by the JIS L 1906 long fibrous nonwoven fabric evaluation method and the physical properties of the carpet products were measured by the method of paragraph 5.8 of JIS L 4406 tile carpet evaluation method And the environmental performance was assessed by using heat and water influences using JIS L 4406 section 7.9. The results are shown in Table 1 below.

For the measurement of the environmental performance for evaluating the performance of the carpet product, the final carpet product was placed on a flat surface for 24 hours in a standard state, dried in an oven at 60 DEG C for 2 hours, and then immersed in water containing 1% And immersed for 2 hours.

This was dried in an oven at 60 ° C for 24 hours, and then allowed to stand on a flat surface for 24 hours on a standard flat surface. The four sides of the carpet were measured by scaling.

Measurement results of physical properties of spunbond nonwoven fabric and carpet Spunbond nonwoven fabric ^{Note 1 )} Tufting carpets ^{Note 1 )} Environmental evaluation The tensile strength
(Kg / 5 cm) Elongation
(%) Phosphorus strength
(㎏ _f) Heat shrinkage ^{Note 2 )}
(%) The tensile strength
(Kg / 5 cm) Phosphorus strength
(㎏ _f) Height
(Mm) Example 1 18/17 32/34 7.6 / 7.8 0.3 / 0.2 14/13 5.8 / 5.5 0.3 Example 2 19/18 36/39 8.3 / 8.5 0.5 / 0.6 16/16 7.5 / 7.4 0.5 Example 3 17/16 28/29 7.2 / 7.4 0.3 / 0.2 12/13 5.4 / 5.6 0.4 Example 4 14/14 26/24 7.8 / 7.8 0.3 / 0.2 11/10 5.9 / 6.1 0.4 Example 5 23/21 34/32 6.4 / 6.3 0.4 / 0.5 12/14 5.2 / 5.1 0.5 Comparative Example 1 20/18 35/38 7.8 / 7.6 0.8 / 0.9 15/14 5.5 / 5.3 1.1 Comparative Example 2 19/16 27/24 6.5 / 6.2 0.3 / 0.4 13/12 4.8 / 4.4 1.5 Comparative Example 3 13/12 18/19 5.8 / 8.8 0.3 / 0.3 6/4 6.3 / 3.2 1.0 Comparative Example 4 18/18 24/26 6.5 / 6.7 0.5 / 0.7 11/12 4.9 / 4.8 1.1 Number of samples 20 20 20 8 20 20 8 Note 1) MD / CD (MD: mechanical direction, CD: cross direction)
Note 2) Measurement after heat treatment at 180 ° C for 3 minutes

As can be seen from Table 1, the nonwoven fabric of the example and the carpet made therefrom were evaluated in terms of tensile strength, elongation, tear strength, heat shrinkage, Which is superior to the comparative example.

In more detail, the tensile strength of the nonwoven fabric was the most excellent in Example 5 in which the low melting point copolymerized polyester contained the largest amount of 10 wt.%, While the tensile strength of the carpet was low melting point copolymer polyester having a melting point of 180 캜 Of Comparative Example 1 containing the low melting point copolymerized polyester having the melting point of 170 캜 was the best and the lowest melting point copolymerized polyester containing 3.6 wt% 3 showed the lowest tensile strength in both nonwovens and carpets.

That is, the tensile strength of the nonwoven fabric increases as the content of the low melting point copolymerized polyester increases, and decreases as the content of the low melting point copolymerized polyester increases. In the case of the carpet, the lower the melting point of the low melting copolymer polyester, .%, The tensile strength is decreased.

In the case of the tear strength, in the nonwoven fabric and the carpet, Example 2 was the most excellent and Comparative Example 3 was the lowest. In Examples, the lower the melting point of the low melting point copolymer polyester was, the lower the tear strength But the content of the low melting point copolymer polyester did not show a certain tendency.

The elongation percentage of the nonwoven fabric was excellent in the order of Example 2> Comparative Example 1, and poor in the order of Example 4 containing 4 wt.% Of the low melting point copolymer polyester in Comparative Example 3, The lower the melting point, the better. The lower the melting point, the better.

The heat shrinkage ratio of the nonwoven fabric of Example 1 containing 6 wt.% Of a low melting point copolymer polyester having a melting point of 190 DEG C, Examples 3 and 190 containing 6 wt.% Of a low melting point copolymer polyester having a melting point of 210 DEG C Comparative Example 1 in which Example 4 containing 4 wt.% Of a low melting point copolymer polyester having a melting point of 60 占 폚 and containing 6 wt.% Of a low melting point copolymer polyester having a melting point of 170 占 폚 was the largest , And it is judged that the lower the melting point of the low melting point copolymer polyester, the larger the heat shrinkage ratio.

As a result of the evaluation of the environmental resistance by measuring the height of the edge portions, the spunbonded nonwoven fabric produced in the example of the present invention was observed to have a margin of 0.5 mm or less, which is much lower than the reference value of 1.5 mm or less, Performance.

As described above, according to the manufacturing method of the spunbonded nonwoven fabric for carpet bubbles of the present invention, a spunbonded nonwoven fabric having excellent physical properties and flexibility at a high temperature of 180 DEG C with a moderate stretching under a tensile force given by a small amount can be manufactured .

In addition, the carpet manufactured using the nonwoven fabric can produce a carpet of high quality with improved shape stability by suppressing the occurrence of peeling due to heat and water while maintaining excellent physical properties of the nonwoven fabric.

Claims (8)

90 to 96% by weight of a high-melting-point polyester having a melting point of 250 to 270 DEG C and 4 to 10% by weight of a low-melting copolymer having a melting point of 180 to 210 DEG C, an elongation of 25 to 40% and a heat shrinkage of 0.2 to 0.6 % Sponge bonded nonwoven fabric for carpet bubbles with improved form stability. The method according to claim 1,
Wherein the high melting point polyester is polyethylene terephthalate or polynaphthalene terephthalate. 2. The spunbond nonwoven fabric according to claim 1, wherein the high melting point polyester is poly (ethylene terephthalate) or poly (naphthalene terephthalate). The method according to claim 1,
The low melting point copolymer is selected from the group consisting of a polyester copolymerized with adipic acid, a polyester copolymerized with isophthalic acid, a polyester copolymerized with adipic acid and isophthalic acid, polybutylene terephthalate, polylactic acid and polyamide Wherein the spunbond nonwoven fabric is at least one of the spunbond nonwoven fabric and the spunbond nonwoven fabric. The method according to claim 1,
Wherein the low melting point copolymer is a copolymer of adipic acid or isophthalic acid with the high melting point polyester. A low melting point copolymer having a melting point of 250 to 270 DEG C and a low melting point copolymer having a melting point of 180 to 210 DEG C at a ratio of 90 to 96: 4 to 10 wt%;
Forming a web of filaments formed by the radiation; And
And thermally bonding the web to the spunbond nonwoven fabric. The method of claim 5,
Wherein the high melting point polyester is polyethylene terephthalate or polynaphthalene terephthalate. 2. The spunbond nonwoven fabric according to claim 1, wherein the high melting point polyester is polyethylene terephthalate or polynaphthalene terephthalate. The method of claim 5,
The low melting point copolymer is selected from the group consisting of a polyester copolymerized with adipic acid, a polyester copolymerized with isophthalic acid, a polyester copolymerized with adipic acid and isophthalic acid, polybutylene terephthalate, polylactic acid and polyamide Wherein the spunbonded nonwoven fabric is at least one of the spunbond nonwoven fabric and the spunbond nonwoven fabric. The method of claim 5,
Wherein the low-melting-point copolymer is obtained by copolymerizing adipic acid or isophthalic acid with the high-melting-point polyester.