KR20190030285A - Multi layer structure sound-absorbing material for vehicle - Google Patents

Abstract

Disclosed is a multi-layered sound absorbing material for a vehicle. More particularly, the multi-layered sound absorbing material for a vehicle comprises: a first sound absorbing layer; and a second sound absorbing layer formed on an upper surface of the first sound absorbing layer. The second sound absorbing layer comprises: 100 parts by weight of polyethylene terephthalate fibers; and 10-50 parts by weight of low melting point polyester fibers. The multi-layered sound absorbing material for a vehicle having the laminated structure has excellent sound absorption performance by applying the first sound absorbing layer and the second sound absorbing layer with increased internal voids.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a multi-

The present invention relates to a sound absorbing material for a vehicle multi-layer structure, and more particularly, to a sound absorbing material for a vehicle having a double-layer structure, wherein a first sound-absorbing layer and a second sound-absorbing layer with increased internal voids are applied to exhibit excellent sound-absorbing performance.

Recently, the technology of reducing the noise of vehicles has been dealt with in terms of customer 's sensibility quality beyond simple performance improvement, and the quietness of the vehicle has become a key item in developing the vehicle to be used in brand marketing.

The improvement of the sound absorption performance of the vehicle is closely related to the material, weight and thickness of the sound absorbing material. In the past, the weight and thickness of the sound absorbing material have been increased to improve the noise of the vehicle. However, .

Recently, porous sound absorbing materials such as glass wool, resin felt, and polyethylene terephthalate felt have been used. This is because the sound absorbing performance in the high frequency region by increasing thickness and weight There is a disadvantage in that it is difficult to improve noise in the middle low frequency region of 2 kHz or less.

A composite sound absorbing material prepared by layering and mixing various sound absorbing materials and sound insulating materials is used together with the above porous sound absorbing material. The conventional composite sound absorbing material is a composite layer type in which a sound absorbing material of a porous structure and a sound insulating material of a non- And may be a laminate of a skin nonwoven fabric and a PU (polyurethane) foam and a skin nonwoven fabric, or a laminate of a skin nonwoven fabric, a resin felt and a rubber, or a laminate of a PU foam, a rubber and a PET felt Lt; / RTI >

Such a conventional composite sound absorbing material can be applied to, for example, a hood insulator of a car, a dash insulator, a dash isopad, etc. However, since the conventional composite sound absorbing material as described above uses a sound insulating material such as rubber, And there is a problem that thickness and weight increase even when the sound insulating material is not included.

Korean Patent Registration No. 10-1033395 (April 28, 2011) Korean Patent Registration No. 10-1582648 (December 29, 2015)

It is an object of the present invention to provide a sound absorbing material for a vehicle multi-layered structure having a first sound-absorbing layer and a second sound-absorbing layer with increased internal voids and exhibiting excellent sound-absorbing performance.

In one embodiment, this disclosure is made up of a first sound-absorbing layer and a second sound-absorbing layer formed on the upper surface of the first sound-absorbing layer, wherein the second sound-absorbing layer comprises 100 parts by weight of the polyethylene terephthalate fiber, And 10 to 50 parts by weight of a melting point polyester fiber.

In another embodiment, the disclosure is made up of a first sound-absorbing layer and a second sound-absorbing layer formed on the upper and lower surfaces of the first sound-absorbing layer, and the second sound-absorbing layer comprises 100 wt% polyethylene terephthalate fibers And 10 to 50 parts by weight of a low-melting-point polyester fiber.

Preferably, the first sound-absorbing layer may have a surface density of 300 to 1500 g / m ² .

More preferably, the first sound-absorbing layer may be made of polyethylene terephthalate fibers.

More preferably, the first sound-absorbing layer may comprise 100 parts by weight of polyethylene terephthalate fibers and 10 to 20 parts by weight of low melting point polyester fibers.

Still more preferably, the first sound-absorbing layer may be composed of 100 parts by weight of polyethylene terephthalate fibers and 1 to 20 parts by weight of elastic fibers.

Still more preferably, the first sound-absorbing layer may be composed of 100 parts by weight of polyethylene terephthalate fibers, 10 to 20 parts by weight of low melting point polyester fibers and 10 to 20 parts by weight of elastic fibers.

Even more preferably, the elastic fiber comprises a low melting point thermoplastic elastomer and may be made of a staple fiber having an elastic recovery rate of 40% or more.

Even more preferably, the second sound-absorbing layer may be formed at a surface density of 30 to 1500 g / m ² .

Still more preferably, the second sound-absorbing layer may further contain 10 to 50 parts by weight of elastic fibers relative to 100 parts by weight of the polyethylene terephthalate fibers.

As described above, the sound absorbing material for a vehicle multi-layer structure has excellent sound absorption performance by applying the first sound absorbing layer and the second sound absorbing layer with increased internal voids.

1 is an exploded perspective view illustrating a sound absorbing material for a vehicle according to an embodiment disclosed herein.
2 is an exploded perspective view showing a sound absorbing material for a vehicle according to another disclosed embodiment.

Hereinafter, preferred embodiments of the present invention and physical properties of the respective components will be described in detail with reference to the accompanying drawings. However, the present invention is not limited thereto, And this does not mean that the technical idea and scope of the present invention are limited.

The disclosed sound absorbing material for a vehicle comprises a first sound-absorbing layer 10 and a second sound-absorbing layer 20 formed on the upper surface of the first sound-absorbing layer 10, and the second sound- 100 parts by weight of a phthalate fiber and 10 to 50 parts by weight of a low melting point polyester fiber.

The disclosed sound absorbing material for a vehicle includes a first sound-absorbing layer 10 and a second sound-absorbing layer 20 formed on the upper and lower surfaces of the first sound-absorbing layer 10, 20 may be composed of 100 parts by weight of polyethylene terephthalate fibers and 10 to 50 parts by weight of low melting point polyester fibers.

The first sound-absorbing layer 10 is a layer which becomes a base material of the disclosed sound-absorbing material for a vehicle, and has a thickness of 1 to 5 mm and a surface density of 300 to 1500 g / m ² , and is made of polyethylene terephthalate fiber, 100 parts by weight of terephthalate fiber and 10 to 20 parts by weight of low melting point polyester fiber, or 100 parts by weight of polyethylene terephthalate fiber and 10 to 20 parts by weight of elastic fiber, or 100 parts by weight of polyethylene terephthalate fiber, 10 to 20 parts by weight of fibers and 10 to 20 parts by weight of elastic fibers.

The polyethylene terephthalate fiber is preferably used as a main component of the first sound-absorbing layer 10 and exhibits a denier of 1 to 10 denier.

The low melting point polyester fiber is contained in an amount of 10 to 20 parts by weight and serves as a binder for melting the polyethylene terephthalate fiber in the course of molding the vehicle sound absorbing material. The polyester fibers are bonded through a process such as needle punching.

The elastic fibers are bonded to the first sound-absorbing layer 10 through a process such as needle punching, and include a low melting point thermoplastic elastomer, and are made of staple fibers having an elastic recovery rate of 40% or more.

The low melting point thermoplastic elastomer may be prepared by mixing dimethyl terephthalate (DMT), dimethyl isophthalate (DMI), or terephthalic acid (TPA) and isophthalic acid (IPA) Can be prepared through esterification and polymerization steps using 1,4-butanediol (1,4-BD) and polytetramethyleneglycol (PTMG) as a diol component (Diol).

The acidic component (Diacid) is obtained by using dimethyl terephthalate (DMT), dimethyl isophthalate (DMI) or terephthalic acid (TPA) and isophthalic acid (IPA), and dimethyl terephthalate (DMT) and terephthalic acid (TPA) react with the diol component to form a crystalline region. Dimethylisophthalate (DMI) and isophthalic acid (IPA) react with the diol component to form an amorphous region, .

The molar ratio of dimethyl terephthalate (DMT) to dimethyl isophthalate (DMI) is preferably in the range of 0.65 to 0.80: 0.2 to 0.35 and the molar ratio of terephthalic acid (TPA) to isophthalic acid (IPA) 0.2 to 0.35. The molar ratio of dimethyl isophthalate (DMI) to isophthalic acid (IPA) is less than the above range, the elastic recovery rate may be lowered, the low melting point function may not be exhibited and dimethyl isophthalate (DMI) and isophthalic acid ) Is more than the above range, the physical properties may be lowered.

The diol component is 1,4-butanediol, 1,4-butanediol, and polytetramethyleneglycol (PTMG). The 1,4-butanediol is an acid component, (PTMG) forms an amorphous region by reacting with an acid component to give a low melting point function and an elastic force.

The mixing ratio of 1,4-butanediol (1,4-BD) and polytetramethylene glycol (PTMG) is preferably in a molar ratio of 0.85 to 0.95: 0.05 to 0.15. The molar ratio of the polytetramethylene glycol (PTMG) is less than the above range, the elastic recovery rate may be lowered, the low melting point function may not be exhibited, and the molar ratio of dipotetramethylene glycol (PTMG) The physical properties may be deteriorated. 1,4-butanediol (1,4-BD) can be mixed with ethylene glycol (EG) within the above range.

The polytetramethylene glycol (PTMG) preferably has a molecular weight of 1,500 to 2,000. The elasticity and physical properties of a low melting point (LM) thermoplastic elastomer produced when the polytetramethylene glycol (PTMG) is out of the range of the molecular weight may not be suitable for use.

It is preferable that the acid component and the diol component are mixed and polymerized at a molar ratio of 0.9 to 1.1: 0.9 to 1.1. If the acid component and the diol component are mixed too much, the acid component and the diol component are preferably used in a similar amount.

As described above, dimethyl terephthalate (DMT) and dimethyl isophthalate (DMI) can be used as an acid component as 1,4-butanediol (1,4-BD), polytetramethylene glycol (PTMG) as a diol component The low melting point (LM) thermoplastic elastomer to be produced can be produced at a melting point of 90 to 150 DEG C and an elastic recovery rate of 50 to 80%.

The staple fiber may be a composite fiber obtained by spinning the low melt point (LM) thermoplastic elastomer as a single component, more preferably a sheath-core type, an eccentric sheath Sheath-core type or side by side type. In the case of forming an eccentric sheath-core type conjugated fiber, the low melting point (LM) thermoplastic It is possible to use a general polyester polymer such as polyethyleneterephthalate, polybutyleneterephthalate or polytrimethyleneterephthalate as a core component with an elastomer as a sheath component . The general polyester has the function of lowering the manufacturing cost and supporting the fiber, and the low melting point (LM) elastomer enables the elasticity and the low melting point function to be expressed.

The elastic fibers produced through the above process serve to provide a sound absorbing material for a vehicle having a double layer structure which is improved in sound absorption performance by increasing the internal voids of the first sound absorbing layer 10. The elastic fibers exhibit the above- An E-plex from Chemitel Corp. may also be used.

It said second sound absorbing layer 20 is the first sound absorbing layer 10, the upper surface or the first sound absorbing layer 10, a top surface and a thickness of 1 to 5 mm to the lower surface and 30 to the 1500g / m ² of the And is composed of 100 parts by weight of polyethylene terephthalate fibers and 10 to 50 parts by weight of low melting point polyester fibers. The sound absorbing performance of the second sound absorbing layer (20) is primarily absorbed, And serves to provide a vehicle-use double layered sound absorbing material.

In addition, the second sound-absorbing layer 20 may further contain 10 to 50 parts by weight of elastic fibers relative to 100 parts by weight of the polyethylene terephthalate fibers. The content and the role of the elastic fibers may vary depending on the material of the first sound- And therefore, a description thereof will be omitted.

Hereinafter, a description will be made of a method for manufacturing a sound absorbing material for a vehicle and a physical property of a sound absorbing material for a vehicle manufactured through the method.

≪ Example 1 >

A first sound-absorbing layer having a surface density of 500 g / m ² and a thickness of 3.5 mm is formed by polyethylene terephthalate fibers (7 denier), and a surface density of 500 g / m ² and a thickness of 1.5 mm are formed on the upper surface of the first sound- And a second sound-absorbing layer consisting of 100 parts by weight of polyethylene terephthalate fibers and 30 parts by weight of low melting point polyester fibers were laminated and then needle punched was subjected to a preheating process and a cooling molding process to form a double layer sound absorbing material .

≪ Example 2 >

A first sound-absorbing layer consisting of 100 parts by weight of polyethylene terephthalate fibers (1.5 denier) and 20 parts by weight of low melting point polyester fibers and having a surface density of 500 g / m ² and a thickness of 3.5 mm was formed in the same manner as in Example 1 And a second sound-absorbing layer having a surface density of 500 g / m ² and a thickness of 1.5 mm was formed on the upper surface of the first sound-absorbing layer by mixing 100 parts by weight of polyethylene terephthalate fibers and 30 parts by weight of low melting point polyester fibers, Structure sound - absorbing material.

≪ Example 3 >

100 parts by weight of the polyethylene terephthalate fibers (1.5 denier) and 20 parts by weight of elastic fibers (E-plex) fibers were blended together to give a surface density of 500 g / m ² and a thickness of 3.5 mm the first sound absorbing layer is made to form and the top surface of the first sound-absorbing layer of polyethylene terephthalate fibers 100 parts by weight and 30 parts by weight of low melting point polyester fiber the area density is 500g / m ² and a thickness of 1.5 mm a second A sound absorbing layer was formed to fabricate a sound absorbing material for a vehicle.

<Example 4>

(7 denier), 20 parts by weight of low-melting-point polyester fibers and 10 parts by weight of an elastic fiber (E-plex) fiber, and the surface density of the polyethylene terephthalate fiber Wherein the first sound-absorbing layer has a surface area of 500 g / m ² and a thickness of 4 mm. The first sound-absorbing layer has 100 parts by weight of polyethylene terephthalate fibers and 30 parts by weight of low melting point polyester fibers. ² and a thickness of 1 mm was formed on the second sound-absorbing layer to prepare a sound-absorbing material for a vehicle multi-layer structure.

&Lt; Comparative Example 1 &

100 parts by weight of polyethylene terephthalate fibers and 30 parts by weight of low melting point polyester fibers were needle-punched and subjected to a preheating process and a cooling molding process to produce a sound absorbing material for vehicles having a thickness of 5 mm and a surface density of 1000 g / m ² .

&Lt; Comparative Example 2 &

A first sound-absorbing layer consisting of 100 parts by weight of a polyethylene terephthalate fiber and 30 parts by weight of a low melting point fiber and having a surface density of 500 g / m ² and a thickness of 3 mm is formed, , A second sound-absorbing layer having a surface density of 500 g / m ² and a thickness of 2 mm was formed and then needle punching was carried out to obtain a sound absorbing material for a vehicle having a thickness of 5 mm through a preheating process and a cooling molding process .

The sound absorption performance of the sound absorber manufactured through Example 1 and Comparative Examples 1 and 2 was measured and shown in FIG.

(However, the sound absorption rate was measured by using the Semi Reverberation Chamber (SRC) method, which is a 1/3 size standard reverberation room, which is a method for measuring the sound absorption rate of the manufactured vehicle, to a size of 840 mm × 840 mm This is expressed as the average of the measured values.

As shown in FIG. 3, all of the sound absorbing materials for a vehicle manufactured through Example 1 showed a sound absorbing effect superior to that of the sound absorbing materials for vehicles manufactured in Comparative Examples 1 and 2 in the frequency band.

In addition, the sound absorption performance of the sound absorbing material manufactured through Examples 2 to 4 and Comparative Example 1 was measured and is shown in FIG. 4 below.

(However, the sound absorption rate was measured by using the Semi Reverberation Chamber (SRC) method, which is a 1/3 size standard reverberation room, which is a method for measuring the sound absorption rate of the manufactured vehicle, to a size of 840 mm × 840 mm This is expressed as the average of the measured values.

As shown in FIG. 4, all of the sound absorbing materials for a vehicle manufactured through Examples 2 to 4 showed a sound absorbing effect superior to a sound absorbing material for a vehicle manufactured in Comparative Example 1 in a frequency band.

In particular, it can be seen that the sound absorbing material for vehicles manufactured through the disclosed embodiments 3 to 4 contains elastic fibers, and the sound absorbing performance is further improved.

Accordingly, it can be seen that the disclosed sound absorbing material for a vehicle multi-layer structure has excellent sound absorption performance by applying the first sound-absorbing layer and the second sound-absorbing layer with increased internal voids.

10; The first sound-
20; The second sound-

Claims (10)

A first sound-absorbing layer; And
And a second sound absorbing layer formed on an upper surface of the first sound absorbing layer,
Wherein the second sound-absorbing layer comprises 100 parts by weight of a polyethylene terephthalate fiber and 10 to 50 parts by weight of a low melting point polyester fiber.
A first sound-absorbing layer; And
And a second sound-absorbing layer formed on upper and lower surfaces of the first sound-absorbing layer,
Wherein the second sound-absorbing layer comprises 100 parts by weight of a polyethylene terephthalate fiber and 10 to 50 parts by weight of a low melting point polyester fiber.
The method according to claim 1 or 2,
Wherein the first sound-absorbing layer is formed at a surface density of 300 to 1500 g / m &lt; ² &gt;.
The method according to claim 1 or 2,
Wherein the first sound-absorbing layer is made of polyethylene terephthalate fiber.
The method according to claim 1 or 2,
Wherein the first sound-absorbing layer comprises 100 parts by weight of a polyethylene terephthalate fiber and 10 to 20 parts by weight of a low melting point polyester fiber.
The method according to claim 1 or 2,
Wherein the first sound-absorbing layer comprises 100 parts by weight of a polyethylene terephthalate fiber and 1 to 20 parts by weight of an elastic fiber.
The method according to claim 1 or 2,
Wherein the first sound-absorbing layer comprises 100 parts by weight of polyethylene terephthalate fibers, 10 to 20 parts by weight of low melting point polyester fibers, and 10 to 20 parts by weight of elastic fibers.
The method of claim 6,
Wherein the elastic fiber comprises a low melting point thermoplastic elastomer and is made of a staple fiber having an elastic recovery rate of 40% or more.
The method according to claim 1 or 2,
And the second sound-absorbing layer is formed at a surface density of 30 to 1500 g / m &lt; ² &gt;.
The method according to claim 1 or 2,
Wherein the second sound-absorbing layer further contains 10 to 50 parts by weight of elastic fibers relative to 100 parts by weight of the polyethylene terephthalate fiber.

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