KR102564979B1 - Vehicle interior panel comprising for binder - Google Patents

Abstract

The present invention includes a fiber layer in which a first polyester fiber containing a polyester resin with a melting point higher than 250 ° C. and a second polyester fiber containing a polyester resin for a binder having a softening point of 100 ° C. to 150 ° C. are mixed, The second polyester fiber is a polyester fiber for a binder formed of a sheath part and a core part, and the core part is formed of a general polyester resin, and the sheath part is formed of a polyester resin of the following [Formula 1], and the sheath part The polyester resin relates to an automobile interior material including a polyester fiber for a binder having a difference between a melt viscosity of 220° C. and a melt viscosity of 260° C. of 700 poise or less.
[Formula 1]

However, m and n are mol%, m+n=100%, and a is the degree of polymerization

Description

Automobile interior material containing polyester fiber for binder {VEHICLE INTERIOR PANEL COMPRISING FOR BINDER}

The present invention relates to an interior material for automobiles containing polyester fibers for a binder, and relates to an interior material for automobiles containing polyester fibers for a binder, which has excellent shape stability and excellent sound absorption when thermoforming using low-melting polyester fibers. will be.

Automobiles are equipped with exterior parts such as doors and fenders, or interior materials such as seats, door trims, and package tray panels. The body part of an automobile must provide stability, space, comfort, and the like to occupants including a driver.

In general, automotive interior materials combine fibers with a thermoplastic resin or a mixture of a thermoplastic resin and a thermosetting resin to form a sheet, preheated to about 120 ° C, and a thermosetting adhesive layer capable of curing a surface material thereon at a temperature of 120 ° C or less. After attaching via a medium, laminates were prepared by cold compression molding.

Since the above method heats the sheet at a relatively low temperature of about 120° C., the surface material does not deteriorate as it deteriorates at a high temperature. However, since the thermoplastic resin acting as a binder is not sufficiently melted at the low temperature described above, the bonding strength between the fibers is weak, resulting in poor durability.

Recently commercialized automotive interiors are mainly manufactured using fiber-reinforced resin boards or polyurethane-based foams.

The fiber-reinforced resin board is manufactured by converting a polypropylene resin reinforced with natural fibers such as hemp fibers into a board. However, since these fiber-reinforced resin boards use natural fibers, the working environment is poor due to odors generated during product molding, and the odors generated when applied to vehicles cause consumer dissatisfaction. In addition, while microorganisms such as molds propagate in the natural fibers applied to the fiber-reinforced resin board, there is a risk of generating odors and releasing components harmful to the health of occupants. In addition, the fiber-reinforced resin board using the natural fibers has a disadvantage in that weight reduction is difficult.

Alternatively, a package tray panel using a polyurethane-based foam has a problem of discharging toxic gases during an incineration process. In addition, the polyurethane-based foam has a soft property when pressed by hand. In order to compensate for this, glass fibers or glass fragments are incorporated to manufacture interior materials for automobiles.

Republic of Korea Patent Registration No. 0128075 relates to an automobile interior material and a method for manufacturing the same, which includes a needled glass fiber sheet containing a thermoplastic resin binder, and a support layer in which the needled glass fiber is mainly composed of glass fiber; an air-permeable heat-sealable adhesive layer installed on the support layer; And it is made of an air-permeable surface layer installed on the adhesive layer, and the support layer further contains foamed microbeads.

As described above, the interior material for automobiles using glass fibers or pieces of glass has a problem in that the weight increases, and glass dust is generated during manufacturing and transportation, thereby impairing the working environment of workers.

The present invention was invented to solve the problems of the prior art as described above, and the spinning processability of polyester fibers for binders constituting interior materials for automobiles is improved, so that processability and form stability are excellent through improved thermal bonding properties. An object of the present invention is to provide an automobile interior material comprising polyester fibers.

In addition, an object of the present invention is to provide an interior material for a car including a polyester fiber for a binder in which sound absorption is improved by forming an air layer therein.

The present invention includes a fiber layer in which a first polyester fiber containing a polyester resin with a melting point higher than 250 ° C. and a second polyester fiber containing a polyester resin for a binder having a softening point of 100 ° C. to 150 ° C. are mixed, The second polyester fiber is a polyester fiber for a binder formed of a sheath part and a core part, and the core part is formed of a general polyester resin, and the sheath part is formed of a polyester resin of the following [Formula 1], and the sheath part The polyester resin provides an automobile interior material including a polyester fiber for a binder, characterized in that the difference between the melt viscosity at 220° C. and the melt viscosity at 260° C. is 700 poise or less.

[Formula 1]

However, m and n are mol%, m+n=100%, and a is the degree of polymerization

In addition, the first polyester fiber and the second polyester fiber provides an automobile interior material comprising a polyester fiber for a binder, characterized in that the black dyed yarn.

In addition, the first polyester fiber provides a vehicle interior material including a polyester fiber for a binder, characterized in that the cross-section of any one of three-leaf, four-leaf, six-leaf, eight-leaf.

In addition, the second polyester fiber provides an automobile interior material comprising a polyester fiber for a binder, characterized in that the sheath-core type fiber having a hollow.

In addition, the polyester resin of the sheath part provides an automobile interior material including a polyester fiber for a binder, characterized in that the melt viscosity at 260 ℃ is 500 ~ 1,300 poise (poise).

In addition, the polyester resin of the sheath part provides an automobile interior material including a polyester fiber for a binder, characterized in that the molecular weight distribution (Mw / Mn) is 2.0 to 3.5.

In addition, n in [Formula 1] provides an automobile interior material comprising a polyester fiber for a binder, characterized in that 30 to 50 mol%.

In addition, a of [Formula 1] provides an automobile interior material comprising a polyester fiber for a binder, characterized in that 50 to 100.

As described above, the interior material for automobiles including polyester fibers for binders according to the present invention uses low-melting polyester fibers with improved spinning processability and improved heat adhesion, so that the bonding between fibers is excellent even in low-temperature thermoforming, and the shape stability is excellent. It has an excellent effect.

In addition, the interior material for automobiles containing the polyester fiber for binder of the present invention has an effect of improving the sound absorption rate because many air layers are contained in the interior material.

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

As used herein, the terms 'about', 'substantially', and the like are used in a sense at or approximating that number when manufacturing and material tolerances inherent in the stated meaning are given, and are intended to convey an understanding of the present invention. Accurate or absolute figures are used to help prevent exploitation by unscrupulous infringers of the disclosed disclosure.

The present invention is a low-melting 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. It relates to an automobile interior material comprising a melting point polyester fiber.

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 co-polyester resin copolymerized with a functional compound for functionality.

As the polyester resin having a melting point higher than 250° C., any polyester resin having a high melting point may be used.

The first polyester fiber may be preferably formed into a deformed cross-section yarn having a cross section of any one of 3 leaves, 4 leaves, 6 leaves, and 8 leaves in order to improve the sound absorption rate of automobile interior materials.

As described above, the first polyester fiber having a multi-lobed cross-section improves the sound absorption rate by forming many air layers inside the automobile interior material.

The second polyester fiber is a binder polyester fiber formed of a sheath portion and a core portion. The core portion is formed of a general polyester resin and the sheath portion is formed of a low melting point polyester resin, a polyester resin for a binder.

Any general polyester resin forming the core part can be used, but it is preferable to use a polyethylene terephthalate (PET) resin made of terephthalic acid and ethylene glycol.

The polyester resin for the binder forming the sheath part is formed of a polyester resin of the following [Formula 1].

[Formula 1]

However, m and n are mol%, m+n=100%, and a is the degree of polymerization

The polyester resin of the sheath part is a polyester resin containing a composition that does not have a benzene ring as shown in Formula 1, and the number of benzene rings is reduced compared to the polyester resin formed of terephthalic acid and ethylene glycol to increase the flowability of the entire molecular chain increases and the melting point decreases.

In addition, the polyester resin for a binder of the present invention can improve sagging property when formed into a fiber, film, or molded article by increasing packing property due to a decrease in benzene rings in the molecular chain.

When the polyester resin for a binder of the present invention contains 30 mol% or more of n, the polymer becomes amorphous and has thermal properties similar to those of the conventional low-melting polyester resin for a binder containing isophthalic acid. It plays a role in improving tear properties when binding nonwoven fabric by improving elasticity due to flexible molecular chains present in the polymer backbone.

That is, according to the content of the composition having no benzene ring of the polyester resin for a novel binder of the present invention, the degree of freedom of the main chain is increased and the crystallinity of the resin is reduced, thereby increasing the softening point (Ts) and / or glass transition temperature (Tg). can be adjusted. This may exhibit the same effect as the case of using isophthalic acid (IPA) containing an asymmetric aromatic ring in order to lower the crystallinity of a conventional crystalline polyester resin.

Therefore, it is preferable that n is 30 to 50 mol%. If n is less than 30 mol%, the low melting point characteristic may not be expressed so that the polyester resin has crystallinity, and if n exceeds 50 mol%, the benzene ring is formed. The content of components not having is increased, and physical properties of the polyester resin may be deteriorated.

In addition, if the degree of polymerization is too small, physical properties of the polyester are deteriorated, and if the degree of polymerization is too large, the polymerization process may be difficult and may take a long time.

The novel polyester resin for a binder of the present invention formed as described above has a difference between the melt viscosity of 220 ° C. and the melt viscosity of 260 ° C. of 700 poise or less, so that the melt viscosity does not rapidly decrease at high temperatures. It is an ester resin.

The lower the difference between the melt viscosity of the polyester resin at 220° C. and the melt viscosity at 260° C., the better the processability.

The difference between the melt viscosity of 220 ° C. and the melt viscosity of 260 ° C. of the polyester resin for the binder can reduce the drop in melt viscosity as the temperature rises, so that the difference in melt viscosity can be adjusted to 700 poise or less. As such, the melt viscosity of the polyester resin may be adjusted according to molecular weight and molecular weight distribution (Mw/Mn).

The polyester resin for a binder according to the present invention preferably has a molecular weight distribution (Mw/Mn) of 2.0 to 4.0 so as to maintain a high melt viscosity at high temperatures.

In general, the molecular weight and molecular weight distribution of polyester resin can increase the molecular weight and molecular weight distribution by suppressing the reverse reaction in the polymerization process. can drop

In order to produce the molecular weight distribution less than 2, it is necessary to polymerize for a long time under high temperature and high pressure, so the polyester resin of the sheath part according to the present invention preferably has a molecular weight distribution (Mw / Mn) of 2.0 or more, and if the molecular weight distribution exceeds 4.0 Since the melt viscosity may drop rapidly at high temperatures, it is preferable that the molecular weight distribution is 4.0 or less.

The molecular weight distribution (Mw/Mn) of the polyester resin of the sheath part according to the present invention is most preferably 2.0 to 3.5.

As described above, the polyester resin for binder of the sheath part formed by [Formula 1] has a softening temperature of 100 ° C to 150 ° C, a glass transition temperature (Tg) of 50 ° C to 90 ° C, and an intrinsic viscosity of 0.50 dl / g or more. have properties.

The second polyester fiber is preferably formed of a sheath-core type fiber having a hollow, and the air layer through the multi-leaf shape of the first polyester fiber and the hollow of the second polyester fiber through the multi-lobed cross-section of the first polyester fiber are more inside the automobile interior material. By securing more air layers, the sound absorption rate of automobile interior materials can be further increased.

In general, since automobile interior materials are often manufactured in black color, the first polyester fiber and the second polyester fiber are prepared with black dyed yarn by containing black pigments such as carbon black during fiber manufacturing, so that they can be made black without a separate dyeing process. It will be possible to form it into a car interior material of color.

When the first polyester fiber and the second polyester fiber are prepared into dope yarn, black dope yarn may be prepared by containing 0.5 to 3% by weight of a pigment such as carbon black based on the weight of the polyester fiber.

As described above, the present invention is an automobile interior material formed of the first polyester fiber and the second polyester fiber, wherein the first polyester fiber and the second polyester fiber are partially fused to each other, and the fibers are partially fused to each other. The formed form is applied with heat and / or pressure in the process of forming a fiber layer through thermoforming, and in the process, the fibers form a partially fused form with each other.

The first polyester fiber and the second polyester fiber forming the automobile interior material are preferably mixed at a weight ratio of 1:9 to 9:1 to form a fiber layer, and when the content of the second polyester fiber is low, the portion between the fibers Form stability may be reduced due to weak fusion, and physical properties such as strength of the interior material for automobiles may be deteriorated when the content of the second polyester fiber is high.

In the interior material for automobiles including polyester fibers for a binder according to the present invention, a fiber layer in which the first polyester fibers and the second polyester fibers are uniformly mixed is formed and thermally formed at 100 to 200° C. to partially fuse the fibers to each other. can be formed and formed into a certain shape.

When the shape retention rate is high during thermoforming, the automotive interior material has high shape stability at high temperatures, and the shape retention rate during thermoforming is preferably 95% or more, more preferably the shape retention rate is 98% or more.

Hereinafter, examples of a method for manufacturing an automobile interior material including polyester fibers for a binder according to the present invention are shown, but the present invention is not limited to the examples.

◈ Production of the 2nd polyester fiber

Preparation Examples 1 to 6

Polyethylene terephthalate having a melt viscosity of about 2,300 poise at 280 ° C was used as the core part, and a polyester resin for a binder was used as the sheath part, and the weight ratio of the sheath part and the core part was 50:50 through a general composite spinning process. A polyester fiber for a binder with improved processability was prepared.

The polyester resin for the sheath part binder was polymerized using monomers of the following [Formula 2], [Formula 3], and [Formula 4] so that n of [Formula 1] had 45 mol%.

As shown in Table 1 below, the polyester resin for a binder was prepared by constantly adjusting the intrinsic viscosity to about 0.56 dl/g, and having different molecular weights and molecular weight distributions according to preparation examples.

[Formula 2]

[Formula 3]

[Formula 4]

division softening point
(℃) Tg
(℃) IV
(dl/g) Mn Mw molecular weight distribution degree of polymerization
(a) Melt viscosity (poise) 220℃ 240℃ 260℃ Preparation Example 1 118.3 68.9 0.566 10800 45100 4.17 56.3 1037 833 461 Preparation Example 2 119.2 69.8 0.563 13000 47600 3.66 65.2 1197 892 517 Preparation Example 3 118.7 69.7 0.567 13700 45900 3.35 71.3 1234 978 813 Production Example 4 116.7 69.4 0.561 13200 40900 3.09 72.1 1308 1136 981 Preparation Example 5 117.1 68.9 0.565 13900 37400 2.69 73.4 1398 1232 1071 Preparation Example 6 116.1 69.5 0.563 13500 32100 2.37 78.7 1511 1371 1233

As shown in Table 1, it can be seen that the melt viscosity increases as the molecular weight distribution decreases, and through Preparation Example 3, the degree of polymerization is 3.5 or less and the melt viscosity at 260 ° C is 800 poise or more, which can maintain a high melt viscosity at high temperature. Able to know.

In addition, it can be seen that the molecular weight distribution is lowered when the degree of polymerization is increased, and through Examples 3 to 6, the difference between the melt viscosity at 220 ° C. and the melt viscosity at 260 ° C. at a polymerization degree of 3.5 or less is 200 to 500 poise. It can be seen that the difference is very small.

◈ Measurement of physical properties of Preparation Examples 1 to 6

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

(1) Measurement of softening point (or melting point) and glass transition temperature (Tg)

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). did

(2) Intrinsic viscosity (IV) measurement

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

(3) Measurement of melt viscosity

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 Initial Frequency = 1.0 rad/s to Final Frequency = 500.0 rad/s under Frequency Sweep conditions at the set temperature, the value at 100 rad/s was calculated as the melt viscosity.

(4) Measurement of compression hardness

After opening 5 g of polyester fiber and stacking it in a circular mold with a diameter of 10 cm to a height of 5 cm, it was thermally bonded at a set temperature for 90 seconds to prepare a cylindrical molded product. The manufactured molded article was compressed by 75% using Instron, and the compressive hardness was measured by measuring the load applied to 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 formula by measuring the amount of polyester resin used and the amount of spun fibers for 24 hours.

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

(6) molecular weight measurement

The number average molecular weight (Mn) and weight average molecular weight (Mw) of the polyester resin were measured by GPC analysis.

* GPC (Gel permeation chromatograph) analysis instrument conditions

1) Analytical device: Tosoh's EcoSEC HLC-8320 GPC

2) Detector: RI-Detector

3) Developing solvent: CHCl ₃ (chloroform)

4) Column : 2 X Shodex LF-804 + Shodex KF-802.5 (7.8 x 300mm)

5) Temperature: 40℃

6) Flow rate: 1.0mL/min

7) Standard material: Polystyrene

division Compression hardness (kgf) spinning yield
(%, 24hr) 140℃ 150℃ 160℃ Preparation Example 1 0.49 0.66 0.71 98.1 Preparation Example 2 0.52 0.79 0.84 98.3 Preparation Example 3 0.58 0.85 0.93 98.9 Production Example 4 0.61 0.99 1.19 98.9 Preparation Example 5 0.69 1.18 1.30 99.1 Preparation Example 6 0.79 1.24 1.36 99.7

As for the compression hardness, the higher the value, the better the thermal adhesion between the fibers of the molded product. It can be seen that the spinning yield is also excellent.

As described above, the molecular weight distribution of the polyester resin for binder of the sheath part according to the present invention has a close relationship with spinning processability and thermal adhesion, and as the molecular weight distribution increases, the processability and thermal adhesion improve, but the molecular weight distribution is It is difficult to manufacture less than 2, and the polyester resin for binder according to the present invention preferably has a molecular weight distribution of 2 to 4, more preferably 2.0 to 3.5.

In addition, all of Examples 1 to 6 had a spinning yield of 97% or more, and it can be seen that the processability is excellent when manufacturing fibers using the novel polyester resin for binder of the present invention.

◈ Manufacture of interior materials for automobiles

Examples 1 to 3

As the first polyester fiber, polyethylene terephthalate having a melting point of about 265 ° C was used, and the cross-sectional shape was changed according to the examples as shown in Table 3.

In the case of the second polyester fiber, Examples 1 and 2 used the polyester fiber for the binder prepared in Preparation Example 3, and Example 3 was the same as Preparation Example 4, but was prepared and used in a hollow shape.

After forming the first polyester fiber and the second polyester fiber to each of the fiber lengths of 51 mm, they were uniformly mixed with a carding machine at a weight ratio of 60:40 and thermoformed at about 130 ° C to obtain polyester for a binder according to the present invention. An automobile interior material containing fibers was prepared.

Table 3 shows the composition, shape retention rate, thickness and average surface density of the automotive interior materials of Examples 1 to 3.

Comparative Examples 1 to 3

In Comparative Example 1, polyethylene terephthalate having a melting point of about 265 ° C was used as the first polyester fiber and a circular cross-section was used, and the second polyester fiber was terephthalic acid (66.5 mol%) and isophthalic acid (33.5 mol%) as acid components. mol%) was used, and a polyester resin for a binder formed of diethylene glycol (10.5 mol%) and ethylene glycol (89.5 mol%) as a diol component was used to prepare fibers as in Preparation Example 1.

Comparative Example 2 used the same polyester resin for a binder as in Comparative Example 1, but was made of hollow fibers.

Comparative Example 3 was prepared in the same manner as Comparative Example 1, but the first polyester fiber was an 8-leaf cross-section fiber.

Table 3 shows the composition, shape retention rate, thickness and average surface density of the automotive interior materials of Comparative Examples 1 to 3.

* Measurement of shape retention

After the carding process, 5 g of the mixed fiber is taken and placed in a 300 cm 3 cylindrical case (A), followed by treatment at 140 ° C for 60 sec to measure the change in volume (B)

* Shape retention rate (%) = (B/A) × 100

division First polyester fiber
Second polyester fiber
Thickness (㎛) average areal density
(㎡) shape retention rate
(%) section Fineness (D) section Fineness (D) Example 1 octagonal 4 circle 6 20 1,621 98.2 Example 2 six-lobed 4 circle 6 20 1,626 98.9 Example 3 three-lobed 4 hollow 6 20 1,614 98.4 Comparative Example 1 circle 4 circle 6 20 1,600 90.5 Comparative Example 2 circle 4 hollow 6 20 1,621 92.7 Comparative Example 3 octagonal 4 circle 6 20 1,593 91.6

As shown in Table 3, the automotive interior material containing the polyester fiber for binder according to the present invention contains the polyester fiber for binder with improved thermal adhesion through fairness, and Examples 1 to 3 have a shape retention rate of 95% or more. It turns out that it has a shape retention rate very superior to Examples 1-3.

▶ Measurement of sound absorption in Examples and Comparative Examples

After cutting each of the automotive interior materials prepared in the above Examples and Comparative Examples into 1.2 m wide and 1.0 m long to prepare a specimen, the sound absorption coefficient by frequency (Hz) was measured in the following manner, and the average measurement result of these are shown in Table 4 below.

* Measurement of sound absorption coefficient by frequency

In order to measure the sound absorption coefficient, three specimens each of which are applicable to the ISO R 354 and Alpha Cabin methods were prepared, and the sound absorption coefficient was measured after being left for 30 minutes at an external temperature of 0 ℃ and 25 ℃, and the average value of the measured sound absorption coefficient is shown in Table 4 .

division Sound absorption coefficient by frequency
1,000Hz 2,000Hz 3,150Hz 5,000Hz Example 1 0.67 0.76 0.81 0.94 Example 2 0.67 0.70 0.92 0.92 Example 3 0.64 0.71 0.74 0.89 Comparative Example 1 0.51 0.60 0.71 0.83 Comparative Example 2 0.53 0.58 0.63 0.68 Comparative Example 3 0.65 0.72 0.69 0.71

As shown in Table 4, it can be seen that Examples 1 to 3, which are automobile interior materials including the polyester fiber for binder according to the present invention, have a lower sound absorption coefficient than Comparative Examples 1 to 3, and thus have excellent sound absorption.

In addition, it can be seen from Examples 1 and 2 that the sound absorption improves as the number of lobes increases, and from Example 3, it can be seen that the sound absorption improves when the second polyester fiber is hollow.

Claims (8)

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 polyester resin for a binder having a softening point of 100 ° C to 150 ° C are mixed,
The second polyester fiber is a binder polyester fiber formed of a sheath part and a core part, and the core part is formed of a general polyester resin, and the sheath part is formed of a polyester resin of the following [Formula 1],
The polyester resin of the sheath part has a difference between the melt viscosity at 220°C and the melt viscosity at 260°C of 700 poise or less, and the molecular weight distribution (Mw/Mn) is 2.0 to 3.5, and the melt viscosity at 260°C is 800 to 1300. An automobile interior material comprising a polyester fiber for a binder, characterized in that it is poise.
[Formula 1]

However, m and n are mol%, m+n=100%, and a is the degree of polymerization According to claim 1,
The first polyester fiber and the second polyester fiber are automotive interior materials comprising a polyester fiber for a binder, characterized in that the black dyed yarn. According to claim 1,
The first polyester fiber is an automobile interior material comprising a polyester fiber for a binder, characterized in that the cross-section of any one of three, four, six, and eight leaves. According to claim 1,
The second polyester fiber is a hollow sheath-core type fiber. delete delete According to claim 1,
Automotive interior material comprising a polyester fiber for a binder, characterized in that n in [Formula 1] is 30 to 50 mol%. According to claim 1,
Automotive interior material comprising a polyester fiber for a binder, characterized in that a is 50 to 100 in [Formula 1].