KR20200114770A - Wet-laid nonwoven fabric comprising low melting polyester fiber - Google Patents

Abstract

The present invention relates to wet nonwoven fabric including a low-melting point polyester fiber to provide increased physical properties while providing increased thermal adhesion and excellent processability. According to the present invention, the wet nonwoven fabric comprises a first polyester fiber including a polyester resin having a melting point of 250°C or higher and a second polyester fiber including a low-melting point polyester resin having a softening point of 100-150°C. The second polyester fiber includes the low-melting point polyester resin formed by an acid component made of terephthalic acid or an esterification derivate thereof and a diol component including 2-methyl-1,3-propanediol, 2-methyl-1,3-pentanediol, and ethylene glycol.

Description

Wet nonwoven fabric containing low melting point polyester fiber {WET-LAID NONWOVEN FABRIC COMPRISING LOW MELTING POLYESTER FIBER}

The present invention relates to a wet nonwoven fabric comprising a low melting point polyester fiber, and more particularly, to a wet nonwoven fabric comprising a low melting point polyester fiber having improved physical properties by using a fiber containing a novel low melting point polyester resin. will be.

Wet nonwoven fabric refers to a nonwoven fabric manufactured as a sheet by dispersing fibers in water as a nonwoven fabric manufactured by partially changing the paper manufacturing process.

Modern wet-type non-woven technology started commercial production of long-fiber paper in 1934 for the first time, and in the 1940s, paper and wet non-woven fabrics were produced for condensers, vacuum bags, meat wrappers, tea bags, and napkins. ， By using inorganic fibers and various natural fibers, various wet nonwoven fabrics were produced in a true sense.

Fibers used in the manufacture of wet non-woven fabrics include natural fibers such as cellulose fibers such as wood pulp, hemp, and cotton, and protein fibers such as wool and silk, as well as traditional synthetic fibers such as PET and nylon, glass fibers, and ceramic fibers. Various fibers can be used up to inorganic fibers.

Since the fibers used in the wet nonwoven fabric have a relatively short fiber length compared to other nonwoven fabric manufacturing processes, it can be seen that there are no restrictions on raw fibers.

Cellulosic natural fibers such as wood pulp and bast fibers exhibit various fiber lengths according to their types, and fibrillation of fibers is possible through a beating process. Wet nonwoven fabrics made of these fibrillated fibers have excellent strength and high density. It indicates high specificity.

Korean Patent Application Publication No. 2018-0111088 discloses a high-fidelity polyester fiber capable of improving the strength and bulky properties of a wet non-woven fabric with'high-fidelity polyester fiber for wet non-woven fabric and its manufacturing method', Republic of Korea Patent Publication No. 2007-0067884 discloses a filter for automobiles in which a resin layer based on polyurethane is thinly coated to form a porous membrane on the surface of a special paper filter paper composed of pulp as'filter material for air purification and its manufacturing method'. Korean Patent Application Publication No. 2017-0112590 discloses a wet nonwoven fabric having excellent sound absorption, sound insulation, and light weight as'wet nonwoven fabric, a sound-absorbing composite material including the same, and a method for manufacturing the same'. It is used for various purposes by utilizing various fibers.

As described above, among the conventional wet non-woven fabrics, in particular, wet non-woven fabrics using fibers for binders are composed of fibers for binders and various fibers according to the purpose to manufacture wet non-wovens, but conventional fibers for binders have poor adhesion at high temperatures. There was a problem that the strength of the nonwoven fabric was lowered.

The present invention has been invented to solve the problems of the prior art as described above, and an object of the present invention is to provide a wet nonwoven fabric comprising a low-melting polyester fiber having improved heat adhesion, excellent processability, and improved physical properties.

In addition, it is an object of the present invention to provide a wet non-woven fabric comprising a low-melting-point polyester fiber having excellent heat resistance that maintains high strength even at a high temperature due to high adhesion even at high temperatures.

The present invention includes a fiber layer in which a first polyester fiber containing a polyester resin having a melting point higher than 250° C. and a second polyester fiber containing a low melting point polyester resin having a softening point of 100° C. to 150° C. are mixed, The second polyester fiber is an acidic component consisting of terephthalic acid or an ester-forming derivative thereof, and a diol component consisting of 2-methyl-1,3-propanediol, 2-methyl-1,3-pentanediol, and ethylene glycol. It provides a wet nonwoven fabric comprising a low melting point polyester fiber, characterized in that it comprises a low melting point polyester resin to be formed.

In addition, the first polyester fiber provides a wet nonwoven fabric comprising a low-melting polyester fiber, characterized in that the fineness is 0.5 ~ 6 denier, the fiber length is 3 ~ 100mm.

In addition, the second polyester fiber provides a wet nonwoven fabric comprising a low melting point polyester fiber, characterized in that the fineness is 1 to 6 denier, and the fiber length is 1 to 50 mm.

In addition, the second polyester fiber is a polyester fiber for a binder formed of a sheath portion and a core portion, and the core portion is formed of a general polyester resin, and the sheath portion is formed of a low melting point polyester resin. It provides a wet nonwoven fabric comprising polyester fibers.

In addition, the 2-methyl-1,3-pentanediol of the low-melting-point polyester resin provides a wet non-woven fabric comprising a low-melting-point polyester fiber, characterized in that it contains 0.01 to 5 mol% of the diol component.

As described above, the wet nonwoven fabric comprising the low-melting-point polyester fiber according to the present invention has an effect of improving heat adhesion, excellent processability, and improving physical properties.

In addition, the wet-type nonwoven fabric comprising the low-melting-point polyester fiber of the present invention has excellent heat resistance, which maintains high strength even at high temperature due to high adhesion even at high temperatures.

Hereinafter, a preferred embodiment of the present invention will be described in detail. First, in describing the present invention, detailed descriptions of related known functions or configurations are omitted so as not to obscure the subject matter of the present invention.

The terms'about','substantially', etc. of the degree used in the present specification are used at or close to the numerical value when manufacturing and material tolerances specific to the stated meaning are presented, and are used in the sense of the present invention. To assist, accurate or absolute figures are used to prevent unfair use of the stated disclosure by unscrupulous infringers.

The present invention comprises a first polyester fiber containing a polyester resin having a melting point higher than 250° C. and a second polyester fiber containing a low melting point polyester resin having a softening point of 100° C. to 150° C. are mixed. It relates to a wet nonwoven fabric.

The first polyester fiber may be polyethylene terephthalate (PET) formed of terephthalic acid or an ester-forming derivative thereof and ethylene glycol (EG), and may be a copolymerized polyester resin in which a functional compound is copolymerized for functionality.

The polyester resin having a melting point higher than 250° C. may be any polyester resin having a high melting point.

The second polyester fiber is an acidic component consisting of terephthalic acid or an ester-forming derivative thereof, and 2-methyl-1,3-propanediol, 2-methyl-1,3-pentanediol (2-Methyl 1,3 Pentanediol) and ethylene glycol (EG) is a fiber containing a low melting point polyester resin formed of a diol component.

The second polyester fiber is formed by spinning alone with the low melting point polyester resin, or the core part is formed of a general polyester resin and the sheath part is formed of a low melting point polyester resin to improve the physical properties of the second polyester fiber. -It may be a core type composite fiber.

When the second polyester fiber is a cis-core composite fiber, any general polyester resin forming the core part can be used, but a polyethylene terephthalate (PET) resin made of terephthalic acid and ethylene glycol is used. It is preferable that the sheath portion may be formed of the low melting point polyester resin.

The low melting point polyester resin used in the present invention is 2-methyl-1,3-propanediol is a methyl group bonded to the second carbon to facilitate rotation of the polymer main chain, and acts as if it is a polymer end portion, so that the free space between the main chains Widening, increases the flowability of the entire molecular chain. This makes the polymer amorphous and has the same thermal properties as isophthalic acid. Due to the flexible molecular chains present in the polymer main chain, it improves the elasticity and thus improves the tear property when binding the nonwoven fabric.

That is, 2-methyl-1,3-propanediol contains a methyl group (-CH ₃ ) in the ethylene chain bonded to terephthalate as a side chain, thereby securing a space so that the main chain of the polymerized resin can rotate. It is possible to adjust the softening point (Ts) and/or the glass transition temperature (Tg) by inducing an increase and a decrease in crystallinity of the resin. This may exhibit the same effect as in the case of using isophthalic acid (IPA) containing an asymmetric aromatic ring in order to lower the crystallinity of the conventional crystalline polyester resin.

The 2-methyl-1,3-pentanediol has a methyl group bonded to the second carbon like the 2-methyl-1,3-propanediol to facilitate rotation of the polymer main chain and impart low melting point properties to the polyester resin. It has the property of increasing the melt viscosity of the polyester resin with a longer molecular chain than 2-methyl-1,3-propanediol, and prevents the melt viscosity from rapidly decreasing at high temperatures.

The low melting point polyester resin of the present invention formed from the diol component as described above is 20 to 50 mol of the diol component of 2-methyl-1,3-propanediol in the low melting point polyester resin in order to improve the low melting point properties and adhesion. It would be desirable to contain %.

When the 2-methyl-1,3-pentanediol is contained in an amount of less than 0.01 mol% of the diol component, the effect of improving the melt viscosity is insignificant, and when it exceeds 5 mol%, the melt viscosity rapidly increases, thereby deteriorating the spinning processability. It will be preferable that 2-methyl-1,3-pentanediol contains 0.01 to 5 mol% of the diol component.

Most preferably, the 2-methyl-1,3-pentanediol contains 0.05-2 mol%.

The low melting point polyester resin containing 2-methyl-1,3-pentanediol has a difference between the melt viscosity of 220°C and the melt viscosity of 260°C less than 600 poise, so that the melt viscosity does not drop sharply at high temperature. Does not have a certainty.

The difference between the melt viscosity of 220° C. and the melt viscosity of 260° C. of the low melting point polyester resin is the lower, the more preferable it is, and it will be more preferably 500 poise or less.

When the second polyester fiber is formed of a sheath-core composite fiber composed of a sheath part of the low melting point polyester resin, the general polyester resin of the core part has a melt viscosity of 280°C for spinning of the composite fiber in the spinning process. Is 2,000 to 4,000 poise, and the polyester resin of the sheath portion will preferably have a melt viscosity of 500 to 1,400 poise at 260°C.

If the melt viscosity of the general polyester resin of the core portion is too high, the spinning processability may be deteriorated, resulting in a thread trimming phenomenon, and if the melt viscosity of the core portion is lower than that of the polyester resin of the sheath portion, the shape stability of the composite fiber may be reduced. In other words, it is preferable that the fiber cross section of the cis-core type may not be formed, and the general polyester resin of the core portion has a melt viscosity of 2,000 to 4,000 poise at 280°C.

The melt viscosity of the low melting point polyester resin of the sheath part is too high and the shape stability of the composite fiber may be deteriorated, and if the melt viscosity of the sheath part is too low, cross-sectional unevenness, howitzer, and trimming may occur. It is preferable that the melt viscosity of the polyester resin is 600-1,500 poise at 260°C, and more preferably 700 poise or more at 260°C.

The general polyester forming the core part is advantageous for improving the shape stability and spinning processability of the composite fiber in that the melt viscosity of the general polyester resin forming the core part and the melt viscosity of the polyester resin forming the sheath part are different within a certain range. It is preferable that the difference between the melt viscosity of the resin at 280° C. and the melt viscosity at 260° C. of the polyester resin forming the sheath is 700 to 2,500 poise, more preferably 1,000 to 2,000 poise.

As described above, the low melting point polyester resin of the present invention containing 2-methyl-1,3-propanediol and 2-methyl-1,3-pentanediol has a softening temperature of 100°C to 150°C, and a glass transition temperature It has excellent physical properties at 50°C to 90°C and an intrinsic viscosity of 0.50 ㎗/g or more.

It is preferable that the first polyester fiber and the second polyester fiber form a wet nonwoven fabric with short fibers.

The first polyester fiber has a fineness of 0.5 to 6 denier, preferably a fiber length of 3 to 100 mm, and the second polyester fiber has a fineness of 1 to 6 denier, and fiber length is preferably 1 to 50 mm something to do.

In addition, it will be preferable that the first polyester fiber and the second polyester fiber are mixed in a weight ratio of 20:80 to 80:20.

As described above, the present invention is a wet nonwoven fabric formed including a first polyester fiber and a second polyester fiber, and the wet nonwoven fabric can be manufactured by a general wet-lay process. A paper machine or an inclined paper machine may be used to form a web in water, and a low melting point polyester resin of the second polyester fiber may be prepared by bonding the web by heat during the drying process.

The wet nonwoven fabric according to the present invention can be used in a variety of fields, either alone or through laminated paper, and is used for wire inner covering tape, electrical insulating paper, poster, label, air filter, liquid filter, battery separator sheet, sterilized paper, anticorrosive paper, food. It could be used for packaging, etc.

Hereinafter, an example of a method for producing a wet nonwoven fabric including a low melting point polyester fiber according to the present invention is shown, but the present invention is not limited to the examples.

◈ Second polyester fiber manufacturing

Produce Yes 1 to 6

Polyethylene terephthalate having a melt viscosity of about 2,300 poise at 280° C. was used as the core part, and the sheath part was made of a low-melting polyester resin, and the weight ratio of the sheath part and the core part was 50:50. To prepare a polyester fiber for a binder with improved fairness.

In the low melting point polyester resin, terephthalic acid (TPA) and ethylene glycol (EG) were added to an ester reaction tank, and a polymerization reaction was carried out at 258°C to prepare a polyethylene terephthalate polymer (PET oligomer) having a reaction rate of about 96%. I did. In the prepared polyethylene terephthalate (PET), 2-methyl-1,3-propanediol contained about 42 mol% of the diol component, and the content ratio of 2-methyl-1,3-pentanediol was shown in Table 1 below. The mixture was mixed with, and a transesterification catalyst was added to perform a transesterification reaction at 250±2°C. Then, a condensation polymerization reaction catalyst was added to the obtained reaction mixture, and a condensation polymerization reaction was carried out while controlling the final temperature and pressure in the reaction tank to be 280±2° C. and 0.1 mmHg, respectively.

Produce Comparative Example 1

As in Preparation Example 1, polyethylene terephthalate was used as the core part, and the low melting point polyester resin of the sheath part was terephthalic acid (66.5 mol%) and isophthalic acid (33.5 mol%) as the acid component, and diethylene as the diol component. It was prepared using glycol (10.5 mol%) and ethylene glycol (89.5 mol%).

Manufacturing Comparative Example 2

In the same manner as in Preparation Example 1, polyethylene terephthalate was used as the core part, the low melting point polyester resin of the sheath part used terephthalic acid as the acid component, and 2-methyl-1,3-propanediol (42.5 mol%) as the diol component. , It was prepared using ethylene glycol (57.5 mol%).

division Softening point
(℃) Tg
(℃) IV
(dl/g) 2-methyl-1,3-pentanediol (mol%) Melt viscosity 220℃ 240℃ 260℃ Manufacturing Example 1 122 60.9 0.561 0.1 1254 1019 783 Manufacturing Example 2 119 61.8 0.562 0.5 1314 1078 864 Manufacturing Example 3 120 61.9 0.562 1.0 1528 1387 1196 Manufacturing Example 4 123 63.5 0.562 2.0 2271 1739 1444 Manufacturing Example 5 123 64.8 0.563 3.5 2833 2571 2213 Manufacturing Example 6 126 67.3 0.561 5.0 3341 3041 2733 Manufacturing Comparative Example 1 113 56.8 0.563 0 1011 739 467 Manufacturing Comparative Example 2 121 61.5 0.561 0 1197 992 664

As shown in Table 1, it can be seen that the melt viscosity increases as the content of 2-methyl-1,3-pentanediol increases, and in Preparation Examples 1 to 6, the melt viscosity at 260°C is all 700 poise or higher, which is high It can be seen that the melt viscosity is maintained.

In addition, in Preparation Examples 2 to 4 in which 0.5 to 2 mol% of 2-methyl-1,3-pentanediol is contained in the diol component, the difference between the melt viscosity at 220°C and the melt viscosity at 260°C is 300 to 500 poise. It can be seen that the difference is lower than that of Preparation Comparative Examples 1 and 2, which are 684 and 674 poise.

In addition, it can be seen that, as in Preparation Examples 5 and 6, when 2-methyl-1,3-pentanediol is contained in an amount of 3 mol% or more in the diol component, the melt viscosity at 260°C is 2,000 poise or more, and the melt viscosity is rapidly increased. .

▶ Measurement of fiber properties in the manufacturing example and manufacturing comparative example

The following physical properties of the low melting point polyester resin and the polyester fiber for a binder prepared in the Preparation Example and Preparation Comparative Example were measured, and the results are shown in Tables 1 and 2.

(1) Softening point (or melting point) and glass transition temperature (Tg) measurement

The glass transition temperature (Tg) of the copolymerized polyester resin was measured using a differential scanning calorimeter (Perkin Elmer, DSC-7), and the softening behavior was measured in TMA mode using a dynamic mechanical analyzer (DMA-7, Perkin Elmer). I did.

(2) Intrinsic viscosity (IV) measurement

The polyester resin was dissolved in a solution in which phenol and tetrachloroethane were mixed at a ratio of 1:1 by weight at a concentration of 0.5% by weight, and the intrinsic viscosity (I.V) was measured at 35°C using an Uberod viscometer.

(3) Melt viscosity measurement

After melting the polyester resin at the measurement temperature, the melt viscosity was measured using RDA-III of Rheometric Scientific. Specifically, when measured by setting from Initial Frequency = 1.0 rad/s to Final Frequency = 500.0 rad/s under Frequency Sweep condition at the set temperature, the value at 100 rad/s was calculated as the melt viscosity.

(4) Measurement of compression hardness

5 g of polyester fibers were opened, stacked at a height of 5 cm in a circular mold having a diameter of 10 cm, and then thermally bonded at a set temperature for 90 seconds to prepare a cylindrical molded article. The manufactured molded article was compressed by 75% through Instron, and the compressive hardness was measured by measuring the load applied to the compression. In this experiment, the compression hardness was measured by thermal bonding at 140°C, 150°C, and 160°C, respectively.

(5) Measurement of spinning yield (%, 24hr)

The spinning yield was calculated by the following equation by measuring the amount of the polyester resin used for 24 hours and the amount of spun fibers.

Spinning yield (%) = (Amount of spun fiber (kg) / Amount of PET resin used (kg)) * 100

(6) Room temperature and high temperature adhesion measurement

Polyester fibers of Examples and Comparative Examples were heat-sealed to prepare a nonwoven fabric having a density of 2g/100cm2, and the prepared nonwoven fabric was prepared at 25±0.5°C (room temperature) and 100±0.5°C (high temperature) according to ASTM D1424. The adhesion was measured.

(7) High temperature shrinkage

After the polyester fiber for the binder is prepared as short fiber, it is carded to form a cylindrical shape. After applying heat at 170° C. for 3 minutes, the reduced volume is measured. The existing volume is 330 cm3, which can be evaluated as poor shape stability as the volume decreases. Usually, if it is 250 cm 3 or less, the shape stability is inferior, and if it is 280 cm 3 or more, it can be evaluated as excellent.

division Compression hardness (kgf) Spinning yield Adhesion Shape stability 140℃ 150℃ 160℃ (%, 24hr) Room temperature adhesion
[kgf] High temperature adhesion
[kgf] High temperature shrinkage
[Cm3] Example 1 0.55 0.72 0.98 98.5 56.2 4.1 268 Example 2 0.57 0.79 1.07 99.2 57.4 4.3 271 Example 3 0.62 0.88 1.21 99.3 57.3 4.7 275 Example 4 0.61 1.24 1.36 99.5 58.1 4.9 281 Example 5 0.73 1.39 1.55 95.6 58.3 5.1 274 Example 6 0.76 1.54 1.86 91.3 57.2 5.2 271 Comparative Example 1 0.41 0.57 0.74 97.8 55.3 3.2 254 Comparative Example 2 0.52 0.73 0.91 98.1 55.7 3.9 260

The higher the value of the compression hardness, the better the heat adhesion between the fibers of the molded article. As shown in Table 2 above, Preparation Examples 1 to 6, which are the low melting point polyester fibers of the present invention, have higher compression hardness than those of Comparative Example 1,2. It can be seen that the thermal adhesive property is excellent, and the low melting point polyester resins of Examples 1 to 6 and Comparative Examples were both excellently measured at room temperature adhesive strength of 55 kfg or more, but Examples 1 to 6 of the present invention were Comparative Example 1, It can be seen that the adhesive strength is better than 2.

In particular, Preparation Examples 1 to 6 have higher high-temperature adhesive strength than Comparative Examples, and the Examples of the present invention have high-temperature adhesive strength of 4.1 to 5.2 kgf, but Manufacturing Comparative Examples are 3.2 and 3.9, and the Examples of the present invention have very excellent high-temperature adhesive strength. Can be seen.

In addition, it can be seen that both Preparation Examples 1 to 6 and Comparative Examples have a good level of high temperature shrinkage of 260 cm 3 or more, but Preparation Examples 1 to 6 are superior to Preparation Comparative Examples 1 and 2.

In addition, it can be seen that both Examples 1 to 6 and Comparative Examples have a good level of high temperature shrinkage of 260 cm 3 or more, but Examples 1 to 6 are superior to Comparative Examples 1 and 2.

In addition, it can be seen that the difference between the melt viscosity of 220°C and the melt viscosity of 260°C is low. Preparation Examples 2 to 4 have a higher value in the spinning yield. The polyester fiber for the binder of the present invention has excellent fairness and high fairness. It can be seen that the thermal adhesion is improved.

In particular, Preparation Examples 2 to 4 containing 0.5 to 2.0 mol% of the diol component have a spinning yield of 99% or more, excellent adhesion at room temperature and high temperature, and very excellent in high temperature shrinkage. The 2-methyl-1,3- It will be preferable that the pentanediol is contained in an amount of 0.5 to 2.0 mol% in the diol component.

◈ Wet nonwoven fabric manufacturing

Examples 1 to 4

For the first polyester fiber, polyethylene terephthalate having a melting point of about 265°C was used, and in the case of the second polyester fiber, Example 1 was a low melting point polyester fiber of Preparation Example 1, and Example 2 was a low melting point of Preparation Example 2. Polyester fibers, Example 3 used the low melting point polyester fibers of Preparation Example 3, Example 4 was used the low melting point polyester fibers of Preparation Example 4.

The first polyester fiber has a fineness of 1 denier and a fiber length of 6 mm, the second polyester fiber has a fineness of 3 denier and a fiber length of 6 mm, and the first polyester fiber and the second polyester fiber have a weight ratio of 50:50. A wet nonwoven fabric was manufactured by a wet process (Wet-Laid). The basis weight and physical properties of Examples 1 to 4 are shown in Table 3.

Comparative Examples 1 and 2

Although prepared in the same manner as in Example 1, Comparative Example 1 used the low-melting polyester fiber of Preparation Comparative Example 1, and Comparative Example 2 used the low-melting polyester fiber of Comparative Preparation Example 2. The basis weight and physical properties of Comparative Examples 1 and 2 are shown in Table 3.

* Tensile strength: According to KS M 6518, after standing at 260℃ for 300 hours, hold for 60 minutes at a temperature of 23±2℃ and a relative humidity of 50±5%, and then take a specimen and measure the tensile strength at a tensile speed of 200mm/min.

* Flexural strength and flexural modulus: Measured using equipment conforming to ASTM D790.

The size of the test piece is 50mm x 150mm, the length of the span is 100mm, and it is placed in the center of the span and the test piece. At this time, the test speed is 5mm/min, and a compressive load is applied from the outer layer 100 of the test piece.

division Basis weight (g/㎡) Tensile strength (MPa) Flexural strength (N) Flexural modulus (MPa) Example 1 80 155 15 648 Example 2 80 151 17 677 Example 3 81 167 18 704 Example 4 79 169 19 723 Comparative Example 1 80 141 14 581 Comparative Example 2 80 150 15 632

As shown in Table 3, Examples 1 to 4, which are wet nonwoven fabrics containing low-melting-point polyester fibers according to the present invention, contain low-melting-point polyester resins with improved thermal adhesion through fairness, and thus tensile strength, compared to Comparative Examples 1,2, It can be seen that the flexural strength and flexural modulus are excellent.

In addition, as in Examples 2 to 4, the wet nonwoven fabric made of the low melting point polyester fiber of Preparation Examples 2 to 4 excellent in processability and heat adhesion is more physical properties than the wet nonwoven fabric made of the low melting point polyester fiber of Preparation Example 1 You can see that this is better.

Claims (5)

A first polyester fiber containing a polyester resin having a melting point higher than 250° C. and a second polyester fiber containing a low melting point polyester resin having a softening point of 100° C. to 150° C. are mixed with a fiber layer,
The second polyester fiber is an acidic component consisting of terephthalic acid or an ester-forming derivative thereof, and a diol component consisting of 2-methyl-1,3-propanediol, 2-methyl-1,3-pentanediol, and ethylene glycol. Wet nonwoven fabric comprising a low melting point polyester fiber, characterized in that it comprises a low melting point polyester resin to be formed. The method of claim 1,
The first polyester fiber has a fineness of 0.5 to 6 denier, a wet non-woven fabric comprising a low melting point polyester fiber, characterized in that the fiber length is 3 to 100 mm. The method of claim 1,
The second polyester fiber has a fineness of 1 to 6 denier, a wet non-woven fabric comprising a low melting point polyester fiber, characterized in that the fiber length is 1 to 50 mm. The method of claim 1,
The second polyester fiber is a polyester fiber for a binder formed of a sheath portion and a core portion, and the core portion is formed of a general polyester resin, and the sheath portion is formed of a low melting point polyester resin. Wet non-woven fabric containing fibers. The method of claim 1,
2-methyl-1,3-pentanediol of the low melting point polyester resin is a wet nonwoven fabric comprising a low melting point polyester fiber, characterized in that it contains 0.01 to 5 mol% of the diol component.